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Sample records for consumption n-acetyl transferase

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

    DEFF Research Database (Denmark)

    Egeberg, Rikke; Olsen, Anja; Autrup, Herman;

    2008-01-01

    The aim of this study was to investigate whether polymorphisms in N-acetyl transferase 1 and 2 modify the association between meat consumption and risk of breast cancer. A nested case-control study was conducted among 24697 postmenopausal women included in the 'Diet, Cancer and Health' cohort stu...... a modifying effect on the association, indicating that the association is confined to only genetically susceptible women.......The aim of this study was to investigate whether polymorphisms in N-acetyl transferase 1 and 2 modify the association between meat consumption and risk of breast cancer. A nested case-control study was conducted among 24697 postmenopausal women included in the 'Diet, Cancer and Health' cohort study...... (1993-2000). Three hundred and seventy-eight breast cancer cases were identified and matched to 378 controls. The incidence rate ratio (95% confidence interval) for breast cancer was 1.09 (1.02-1.17) for total meat, 1.15 (1.01-1.31) for red meat and 1.23 (1.04-1.45) for processed meat per 25 g daily...

  2. Nourseothricin N-acetyl transferase: a positive selection marker for mammalian cells.

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    Bose S Kochupurakkal

    Full Text Available Development of Nourseothricin N-acetyl transferase (NAT as a selection marker for mammalian cells is described. Mammalian cells are acutely susceptible to Nourseothricin, similar to the widely used drug Puromycin, and NAT allows for quick and robust selection of transfected/transduced cells in the presence of Nourseothricin. NAT is compatible with other selection markers puromycin, hygromycin, neomycin, blasticidin, and is a valuable addition to the repertoire of mammalian selection markers.

  3. UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase. Identification and separation of two distinct transferase activities

    DEFF Research Database (Denmark)

    Sørensen, T; White, T; Wandall, H H;

    1995-01-01

    Using a defined acceptor substrate peptide as an affinity chromatography ligand we have developed a purification scheme for a unique human polypeptide, UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase (GalNAc-transferase) (White, T., Bennett, E.P., Takio, K., Sørensen, T., Bonding, N......., and Clausen, H. (1995) J. Biol. Chem. 270, 24156-24165). Here we report detailed studies of the acceptor substrate specificity of GalNAc-transferase purified by this scheme as well as the Gal-NAc-transferase activity, which, upon repeated affinity chromatography, evaded purification by this affinity ligand...

  4. Isolation of new genes in distal Xq28: transcriptional map and identification of a human homologue of the ARD1 N-acetyl transferase of Saccharomyces cerevisiae.

    Science.gov (United States)

    Tribioli, C; Mancini, M; Plassart, E; Bione, S; Rivella, S; Sala, C; Torri, G; Toniolo, D

    1994-07-01

    In this paper, we describe the physical and transcriptional organization of a region of 140 kb in Xq28, 5' to the L1CAM gene. By isolation and mapping of CpG islands to the physical map of the region, isolation of cDNAs, determination of partial nucleotide sequences and study of the pattern of expression and of the orientation of the transcripts identified we have established a transcriptional map of this region. In this map, previously identified genes (L1CAM, V2R, HCF1 and RnBP) have been positioned as well as 3 new genes. All genes in the region are rather small, ranging in size from 2 to 30 kb, and very close to one another. With the exception of the V2R gene, they are housekeeping, have a CpG island at their 5' end and the same orientation of transcription. This kind of organization is consistent with the one previously described for the more distal portion of Xq28, between the Color Vision (CV) and the G6PD genes and indicates that genes with housekeeping and tissue specific pattern of expression are interspersed in the genome but they are probably found in different 'transcriptional domains'. Among the new genes, TE2 demonstrated 40% identity with the protein N-acetyl transferase ARD1 of S. cerevisiae: TE2 may be the human homologue of the S. cerevisiae gene.

  5. Urinary levels of N-acetyl-S-(2-carbamoylethyl)-cysteine (AAMA), an acrylamide metabolite, in Korean children and their association with food consumption

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Kyunghee [School of Public Health, Seoul National University, Seoul, 151-742 (Korea, Republic of); Department of Biomedical Veterinary Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Occupational and Environmental Health, Yongin University, Yongin, 449-714 (Korea, Republic of); Kang, Sungeun; Lee, Gowoon; Lee, Saeram; Jo, Areum; Kwak, Kyunghee; Kim, Dohyung; Kho, Dohyun; Lee, Sangwoo; Kim, Sunmi; Kim, Sungkyoon [School of Public Health, Seoul National University, Seoul, 151-742 (Korea, Republic of); Hiuang, Yuh-Fang; Wu, Kuen-Yuh [Public Health and Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, National Taiwan University, Taipei, 10617, Taiwan (China); Choi, Kyungho, E-mail: kyungho@snu.ac.kr [School of Public Health, Seoul National University, Seoul, 151-742 (Korea, Republic of)

    2013-07-01

    Acrylamide (AA), a probable human carcinogen, is present in high-temperature-processed foods, and has frequently been detected in humans worldwide. In the present study, the levels of a major AA metabolite, N-acetyl-S-(2-carbamoylethyl)-cysteine (AAMA) were measured in urine samples collected in two separate events with 3 d interval from Korean children (n = 31, 10–13 years old), and their diets were surveyed for 4 d period prior to the second urine sampling. Daily AA intake was estimated from AAMA urinary levels and the influence of food consumption on urinary AAMA levels was investigated. The concentrations of metabolite AAMA in urine ranged between 15.4 and 196.3 ng/mL, with a median level of 68.1 ng/mL, and the levels varied by day considerably even in a given child. Children who were exposed to environmental smoke at home exhibited significantly higher levels of AAMA in urine, suggesting the importance of passive smoking as a source of AA exposure among children. Median (95th percentile) values of daily AA intake in Korean children were 1.04 (2.47) μg/kg body weight/day, which is higher than those reported elsewhere. After adjustment for gender, body mass index, and smoking status of family members, the consumptions of cracker and chocolate were identified to be significantly associated with the concentrations of AAMA in urine. The result of this study will provide information useful for developing public health and safety management for AA. - Highlights: • Urinary AAMA concentrations varied over time by the changes in diet. • Consumption of cracker and chocolate were correlated with urinary AAMA levels. • Urinary AAMA levels were significantly correlated with passive smoking. • AA intake estimates among Korean children are higher than those reported elsewhere.

  6. TGF-β1 Causes EMT by regulating N-Acetyl Glucosaminyl Transferases via Downregulation of Non Muscle Myosin II-A through JNK/P38/PI3K pathway in lung cancer.

    Science.gov (United States)

    Khan, Ghulam Jilany; Gao, Yingsheng; Gu, Ming; Wang, Lai; Khan, Sara; Naeem, Farah; Yousef, Bashir Alsiddig; Roy, Debmalya; Semukunzi, Herve; Yuan, Shengtao; Sun, Li

    2017-08-07

    Epithelial to mesenchymal transition (EMT) is a major determinant of cancer metastasis and is closely linked with TGF-β1. Intracellular proteins, including E. Cadherin, N. Cadherin and Vimentin are directly related to EMT that affect cell migration and adhesion; on the other hand, non muscle myosin (NM) has a central role in cytokinesis, migration and adhesion. We aimed to explore the association of EMT and metastasis with TGF-β1 through regulation of non-muscle myosin II-A (NMII-A) and its interaction with Hexosamine Biosynthesis Pathway (HBP). Protein expression changes were assessed by western blotting and immunofluorescent staining while transcription level changes were assessed by qRT-PCR. EMT was assessed by phenotypic analysis, wound healing, proliferation and transwell migration assay in vitro while in vivo studies were conducted in BALB/c nude mice for lung orthotopic and tail vein metastasis models. We demonstrated that regulation of JNK/ P38/PI3K by TGF-β1 led to down expression of NMII-A which promoted EMT and lung cancer metastasis. This down expression of NMII-A conversely upregulated the expression of Core 2 N-acetyl Glucosaminyl Transferase mucin type (C2GnT-M) and further facilitated up and down regulation of N-acetylglucosaminyltransferase (GnT) -V and -III respectively; moreover, NMII-A K.D cells showed 3 times more tendency to migrate towards brain in vivo. The study reports a novel pathway through which NMII-A negatively regulates EMT and metastasis via up regulation of C2GnT-M, GnT-V and down expression of GnT-III. These findings of lung cancer may further be required to study in other cancer types. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  7. Anti-neuroinflammatory and antioxidant effects of N-acetyl cysteine in long-term consumption of artificial sweetener aspartame in the rat cerebral cortex

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    Afaf Abbass Sayed Saleh

    2015-10-01

    Long term consumption of the artificial sweetener aspartame (ASP induced large increments in cortical inflammation and oxidative stress. Daily oral NAC administration can significantly reverse brain-derived neurotrophic factor (BDNF levels, blocked the cyclooxygenase-2 (COX-2 and prostaglandin E2 (PGE2 production with selective attenuation in expression of proinflammatory cytokines of interleukin-6 (IL-6 and tumor necrosis factor-α (TNF-α in the rat cerebral cortex. Also, NAC can significantly replenish and correct intracellular glutathione (GSH levels, modulate the elevated levels of total nitric oxide (TNO and lipid peroxidation (LPO. Conclusions: The present results amply support the concept that the brain oxidative stress and inflammation coexist in experimental animals chronically treated with aspartame and they represent two distinct therapeutic targets in ASP toxicity. The present data propose that NAC attenuated ASP neurotoxicity and improved neurological functions, suppressed brain inflammation, and oxidative stress responses and may be a useful strategy for treating ASP-induced neurotoxicity.

  8. A gas chromatography-mass spectrometry method for the quantitation of N-nitrosoproline and N-acetyl-S-allylcysteine in human urine: application to a study of the effects of garlic consumption on nitrosation.

    Science.gov (United States)

    Cope, Keary; Seifried, Harold; Seifried, Rebecca; Milner, John; Kris-Etherton, Penny; Harrison, Earl H

    2009-11-15

    Biomarkers in urine can provide useful information about the bioactivation of chemical carcinogens and can be used to investigate the chemoprotective properties of dietary nutrients. N-Nitrosoproline (NPRO) excretion has been used as an index for endogenous nitrosation. In vitro and animal studies have reported that compounds in garlic may suppress nitrosation and inhibit carcinogenesis. We present a new method for extraction and sensitive detection of both NPRO and N-acetyl-S-allylcysteine from urine. The latter is a metabolite of S-allylcysteine, which is found in garlic. Urine was acidified and the organic acids were extracted by reversed-phase extraction (RP-SPE) and use of a polymeric weak anion exchange (WAX-SPE) resin. NPRO was quantified by isotope dilution gas chromatography-mass spectrometry (GC-MS) using [13C5]NPRO and N-nitrosopipecolinic acid (NPIC) as internal standards. This method was used to analyze urine samples from a study that was designed to test whether garlic supplementation inhibits NPRO synthesis. Using this method, 2.4 to 46.0 ng NPRO/ml urine was detected. The method is straightforward and reliable, and it can be performed with readily available GC-MS instruments. N-Acetyl-S-allylcysteine was quantified in the same fraction and detectable at levels of 4.1 to 176.4 ng/ml urine. The results suggest that 3 to 5 g of garlic supplements inhibited NPRO synthesis to an extent similar to a 0.5-g dose of ascorbic acid or a commercial supplement of aged garlic extract. Urinary NPRO concentration was inversely associated with the N-acetyl-S-allylcysteine concentration. It is possible that allyl sulfur compounds found in garlic may inhibit nitrosation in humans.

  9. Serum γ-Glutamyl Transferase Is Inversely Associated with Bone Mineral Density Independently of Alcohol Consumption

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    Han Seok Choi

    2016-03-01

    Full Text Available Backgroundγ-Glutamyl transferase (GGT is a well-known marker of chronic alcohol consumption or hepatobiliary diseases. A number of studies have demonstrated that serum levels of GGT are independently associated with cardiovascular and metabolic disorders. The purpose of this study was to test if serum GGT levels are associated with bone mineral density (BMD in Korean adults.MethodsA total of 462 subjects (289 men and 173 women, who visited Severance Hospital for medical checkup, were included in this study. BMD was measured using dual energy X-ray absorptiometry. Cross-sectional association between serum GGT and BMD was evaluated.ResultsAs serum GGT levels increased from the lowest tertile (tertile 1 to the highest tertile (tertile 3, BMD decreased after adjusting for confounders such as age, body mass index, amount of alcohol consumed, smoking, regular exercise, postmenopausal state (in women, hypertension, diabetes mellitus, and hypercholesterolemia. A multiple linear regression analysis showed a negative association between log-transformed serum GGT levels and BMD. In a multiple logistic regression analysis, tertile 3 of serum GGT level was associated with an increased risk for low bone mass compared to tertile 1 (odds ratio, 2.271; 95% confidence interval, 1.340 to 3.850; P=0.002.ConclusionSerum GGT level was inversely associated with BMD in Korean adults. Further study is necessary to fully elucidate the mechanism of the inverse relationship.

  10. 不同级别恶性脑胶质瘤中N-乙酰氨基半乳糖转移酶-14的表达差异%Expression differences of N-acetyl amino galactosyl transferase-14 in the different levels of malignant glioma and the correlation of malignant degree with glial tumors

    Institute of Scientific and Technical Information of China (English)

    扈玉华; 吴建梁; 刘兵; 田红伟

    2014-01-01

    Objective To explore the expression differences of N-acetyl amino galactosyl transferase-14 (GalNAc-T14) in normal brain tissue and different levels of malignant gliomas and to observe the relationship between the expression of GalNAc-T14 with the differentiation and malignant degree of gliomas.Methods By real-time quantitative polymerase chain reaction detecting system (QPCR) and immunohistochemical staining methods,the expression of GalNAc-T14 was detected in 11 cases of Ⅱ grade glioma tissue samples,14 cases of Ⅲ grade glioma tissue specimens,9 cases of Ⅳ grade glioma tissue samples and 16 specimens of normal brain tissue.Results The average optical density values of GalNAc-T14 in normal brain tissue specimens and the specimens of Ⅱ,Ⅲ and Ⅳ grade glioma cells were 0.956 4 ±0.079 1,0.525 6 ±0.064 7,0.298 9 ±0.080 8,and0.151 4 ±0.062 4 respectively by QPCR.Single factor analysis of variance (One-way ANOVA) and LSD,SNK-t analysis comparison showed the expression of GalNAc-T14 in human gliomas was significantly different from that in the normal brain tissue (P < 0.05).The same significance was also found between grade Ⅱ and grade Ⅲ or grade Ⅳ (P < 0.05).Immunohistochemical staining method revealed that the positive rate of the GalNAc-T14 expression was 68.7% in normal brain tissue specimens and 63.6%,42.9% and 33.3% in glioma tissues of grade Ⅱ,Ⅲ and Ⅳ,and there was significant difference between glioma group and normal brain tissue groups (P < 0.05).Different levels of brain glioma cells showed no obvious consistency.Conclusion The expression of GalNAc-T14 was significantly reduced in malignant glioma cells,and was closely related with disease progression.%目的 探讨N-乙酰氨基半乳糖转移酶-14 (GalNAc-T14)在不同级别恶性胶质瘤中的表达差异及其与胶质瘤恶性程度的关系.方法 采用实时荧光定量核酸扩增检测系统(QPCR)方法和免疫组织化学染色方法检测16

  11. 21 CFR 172.372 - N-Acetyl-L-methionine.

    Science.gov (United States)

    2010-04-01

    ... that are intended for use solely under medical supervision to meet nutritional requirements in specific medical conditions and these foods comply with the requirements of part 105 of this chapter, the food... Special Dietary and Nutritional Additives § 172.372 N-Acetyl-L-methionine. The food additive N-acetyl-L...

  12. Chitosan Molecular Structure as a Function of N-Acetylation

    Energy Technology Data Exchange (ETDEWEB)

    Franca, Eduardo F.; Freitas, Luiz C.; Lins, Roberto D.

    2011-07-01

    Molecular dynamics simulations have been carried out to characterize the structure and solubility of chitosan nanoparticle-like structures as a function of the deacetylation level (0, 40, 60, and 100%) and the spatial distribution of the N-acetyl groups in the particles. The polysaccharide chains of highly N-deacetylated particles where the N-acetyl groups are uniformly distributed present a high flexibility and preference for the relaxed two-fold helix and five-fold helix motifs. When these groups are confined to a given region of the particle, the chains adopt preferentially a two-fold helix with f and w values close to crystalline chitin. Nanoparticles with up to 40% acetylation are moderately soluble, forming stable aggregates when the N-acetyl groups are unevenly distributed. Systems with 60% or higher N-acetylation levels are insoluble and present similar degrees of swelling regardless the distribution of their N-acetyl groups. Overall particle solvation is highly affected by electrostatic forces resulting from the degree of acetylation. The water mobility and orientation around the polysaccharide chains affects the stability of the intramolecular O3- HO3(n) ... O5(n+ 1) hydrogen bond, which in turn controls particle aggregation.

  13. Inhibition by acetaminophen of neoplastic initiation elicited in rat liver by the DNA-reactive hepatocarcinogen N-acetyl-2-aminofluorene.

    Science.gov (United States)

    Williams, Gary M; Iatropoulos, Michael J; Jeffrey, Alan M; Duan, Jian-Dong; Perrone, Carmen E

    2007-12-01

    Acetaminophen, a monocyclic phenolic compound and analgesic, when fed at 8900 p.p.m. in the diet, was reported to inhibit the hepatocarcinogenicity in rats of the aromatic amine proximate carcinogen N-hydroxy-N-acetyl-2-aminofluorene. To elucidate the mechanism(s) of this anticarcinogenicity, the present study examined whether acetaminophen at lower doses has the ability to inhibit the initiating effects in the rat liver of the precursor hepatocarcinogen N-acetyl-2-aminofluorene. Male F344 rats were allocated to six groups, which were maintained under reverse light cycle conditions to assure acetaminophen ingestion at the time of N-acetyl-2-aminofluorene administration during the dark phase, which was imposed from 07.00 to 19.00 h. Group 1 served as vehicle control (0.5% carboxymethylcellulose) for N-acetyl-2-aminofluorene, which was administered intragastrically 3 days per week at 2.6 mg/kg for 8 weeks (group 4) to achieve initiation. Acetaminophen was given in the diet either alone at 2400 or 4800 p.p.m. for 9 weeks (groups 2 and 3), or with N-acetyl-2-aminofluorene (groups 5 and 6), starting 1 week before N-acetyl-2-aminofluorene administration. Acetaminophen blood levels were about 1 and 4 microg/ml at the two dietary concentrations. N-acetyl-2-aminofluorene induced hepatocellular preneoplastic lesions measured as hepatocellular altered foci expressing glutathione S-transferase-P, reflecting initiation. Induced foci were reduced with administration of both concentrations of acetaminophen. Acetaminophen by itself produced no DNA adducts nor did it alter the high formation of N-acetyl-2-aminofluorene-DNA adducts, about 200 in 10 nucleotides, measured by nucleotide postlabeling. Acetaminophen did not affect background liver cell proliferation, but significantly reduced N-acetyl-2-aminofluorene-induced increased proliferation measured by proliferating cell nuclear antigen immunostaining. Thus, acetaminophen effectively protected hepatocytes from the initiating

  14. Glutathione S-transferase phenotypes in relation to genetic variation and fruit and vegetable consumption in an endoscopy-based population

    NARCIS (Netherlands)

    Tijhuis, M.J.; Visker, M.H.P.W.; Aarts, J.M.M.J.G.; Peters, W.H.M.; Roelofs, H.M.J.; Camp, op den E.B.G.; Rietjens, I.M.C.M.; Boerboom, A.M.J.F.; Nagengast, F.M.; Kok, F.J.; Kampman, E.

    2007-01-01

    High glutathione S-transferase (GST) activity may contribute to colorectal cancer prevention. Functional polymorphisms are known in the GSTM1, GSTT1, GSTA1 and GSTP1 genes. The influence of these GST polymorphisms and recent fruit and vegetable consumption on GST levels and activity has not been inv

  15. Effects of consumption of Brussels sprouts on intestinal and lymphocytic glutathione S-transferases in humans

    NARCIS (Netherlands)

    Nijhoff, W.A.; Grubben, M.J.A.L.; Nagengast, F.M.; Jansen, J.B.M.J.; Verhagen, H.; Poppel, G. van; Peters, W.H.M.

    1995-01-01

    A high intake of glucosinolate-containing cruciferous vegetables, such as Brussels sprouts (Brassica oleraceae), has been linked to a decreased cancer risk, but the underlying mechanism is still unclear. The aim of this study was to reveal possible modulating effects of consumption of Brussels sprou

  16. [N-ACETYL-β-D-GLUCOSAMINIDASE OF VIBRIO CHOLERAE].

    Science.gov (United States)

    Duvanova, O V; Mishankin, B N; Vodopianov, A S; Sorokin, V M

    2016-01-01

    Study N-acetyl-β-D-glucosaminidase (chitobiase) (EC 3.2.1.30) in strains of Vibrio cholerae of O1/non-O1 serogroups of various origin, that is a component of chitinolytic complex taking into account object of isolation and epidemiologic significance of strains. Cultures of V. cholerae O1/non-O1 serogroup strains were obtained from the museum of live culture of Rostov RIPC. Enzymatic activity analysis was carried out in Hitachi F-2500 fluorescent spectrophotometer using FL Solutions licensed software. NCBI databases were used during enzyme characteristics. N-acetyl-β-D-glucosaminidase in Vcholerae O1/non-O1 serogroup strains was detected, purified by column chromatography, studied and characterized by a number of physical-chemical and biological properties. Comparative computer analysis of amino acid sequence of N-acetyl-β-D-glucosaminidases of V. cholerae (VC2217 gene), Serratia marcescens etc. has allowed. to attribute the enzyme from V. cholerae to glycosyl-hydrolases (chitobiases) of family 20 and classify it according to enzyme nomenclature as EC 3.2.1.30. N-acetyl-β-D-glucosaminidase in V. cholerae of O1/non-O1 serogroups of various origin and epidemiologic significance, participating in chitin utilization was studied and characterized for the first time, and its possible role in biology of cholera causative agent was shown.

  17. Production of N-acetyl-D-neuraminic acid using two sequential enzymes overexpressed as double-tagged fusion proteins

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    Cheng Chung-Hsien

    2009-07-01

    Full Text Available Abstract Background Two sequential enzymes in the production of sialic acids, N-acetyl-D-glucosamine 2-epimerase (GlcNAc 2-epimerase and N-acetyl-D-neuraminic acid aldolase (Neu5Ac aldolase, were overexpressed as double-tagged gene fusions. Both were tagged with glutathione S-transferase (GST at the N-terminus, but at the C-terminus, one was tagged with five contiguous aspartate residues (5D, and the other with five contiguous arginine residues (5R. Results Both fusion proteins were overexpressed in Escherichia coli and retained enzymatic activity. The fusions were designed so their surfaces were charged under enzyme reaction conditions, which allowed isolation and immobilization in a single step, through a simple capture with either an anionic or a cationic exchanger (Sepharose Q or Sepharose SP that electrostatically bound the 5D or 5R tag. The introduction of double tags only marginally altered the affinity of the enzymes for their substrates, and the double-tagged proteins were enzymatically active in both soluble and immobilized forms. Combined use of the fusion proteins led to the production of N-acetyl-D-neuraminic acid (Neu5Ac from N-acetyl-D-glucosamine (GlcNAc. Conclusion Double-tagged gene fusions were overexpressed to yield two enzymes that perform sequential steps in sialic acid synthesis. The proteins were easily immobilized via ionic tags onto ionic exchange resins and could thus be purified by direct capture from crude protein extracts. The immobilized, double-tagged proteins were effective for one-pot enzymatic production of sialic acid.

  18. Phospho-N-Acetyl-Muramyl-Pentapeptide Translocase from Escherichia coli: Catalytic Role of Conserved Aspartic Acid Residues

    Science.gov (United States)

    Lloyd, Adrian J.; Brandish, Philip E.; Gilbey, Andrea M.; Bugg, Timothy D. H.

    2004-01-01

    Phospho-N-acetyl-muramyl-pentapeptide translocase (translocase 1) catalyzes the first of a sequence of lipid-linked steps that ultimately assemble the peptidoglycan layer of the bacterial cell wall. This essential enzyme is the target of several natural product antibiotics and has recently been the focus of antimicrobial drug discovery programs. The catalytic mechanism of translocase 1 is believed to proceed via a covalent intermediate formed between phospho-N-acetyl-muramyl-pentapeptide and a nucleophilic amino acid residue. Amino acid sequence alignments of the translocase 1 family and members of the related transmembrane phosphosugar transferase superfamily revealed only three conserved residues that possess nucleophilic side chains: the aspartic acid residues D115, D116, and D267. Here we report the expression and partial purification of Escherichia coli translocase 1 as a C-terminal hexahistidine (C-His6) fusion protein. Three enzymes with the site-directed mutations D115N, D116N, and D267N were constructed, expressed, and purified as C-His6 fusions. Enzymatic analysis established that all three mutations eliminated translocase 1 activity, and this finding verified the essential role of these residues. By analogy with the structural environment of the double aspartate motif found in prenyl transferases, we propose a model whereby D115 and D116 chelate a magnesium ion that coordinates with the pyrophosphate bridge of the UDP-N-acetyl-muramyl-pentapeptide substrate and in which D267 therefore fulfills the role of the translocase 1 active-site nucleophile. PMID:14996806

  19. Urinary N-acetyl-beta -D-glucosaminidase and its isoenzymes A & B in workers exposed to cadmium at cadmium plating

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    Rajan BK

    2007-07-01

    Full Text Available Abstract Objective The present study was carried out to determine the effect of cadmium exposure on Urinary N-acetyl-beta -D-glucosaminidase and its isoenzymes A and B in workers exposed at cadmium plating. Methods 50 subjects using cadmium during cadmium plating formed the study group. An equal number of age-sex matched subjects working in administrative section formed the control group. Urinary cadmium levels were determined by using a flameless atomic absorption spectrophotometer. Urinary N-acetyl-beta -D-glucosaminidase and its isoenzymes A and B were determined by using spectrophotmetric method. Results A significant increase of urinary total N-acetyl-beta -D-glucosaminidase and its isoenzymes A and B profiles were noted in study as compared to controls. The levels of urinary N-acetyl-beta -D-glucosaminidase and its isoenzymes A and B profiles were positively and significantly correlated with cadmium levels in urine. Multiple regression analysis was used to assess the effect of urinary cadmium or life style confounding factors (age, BMI, smoking and alcohol consumption on urinary N-acetyl-beta -D-glucosaminidase and its isoenzymes A and B. The analysis showed that the study subjects who had urine cadmium levels greater than 5 μg/g of creatinine, work duration >15 years, smoking and body mass index variables were significantly associated with urinary total N-acetyl-beta -D-glucosaminidase but not on isoenzymes A&B. Conclusion The results presented in this study shows that the increased levels of urinary N-acetyl-beta -D-glucosaminidase observed in cadmium-exposed workers could be used as biomarkers for suggesting preventive measure.

  20. Predominance of N-acetyl transferase 2 slow acetylator alleles in ...

    African Journals Online (AJOL)

    Student

    acetylator phenotype were the most predominant NAT2 allelic type and individuals with the phenotype were more likely to ... influence individual variation in cancer susceptibility, responses to ... development of bladder (Hein, 2002) and colon cancers ... temperature ≥ 37.5°C) or having a history of fever in the preceding.

  1. Expression of polypeptide GalNAc-transferases in stratified epithelia and squamous cell carcinomas

    DEFF Research Database (Denmark)

    Mandel, U; Hassan, H; Therkildsen, M H

    1999-01-01

    Mucin-type O-glycosylation is initiated by a large family of UDP-GalNAc: polypeptide N -acetyl-galactosaminyltransferases (GalNAc-transferases). Individual GalNAc-transferases appear to have different functions and Northern analysis indicates that they are differently expressed in different organ...

  2. PURIFICATION OF L-METHIONINE AND N-ACETYL-D-METHIONINE FROM THE MIXTURE OF ENZYMATICALLY DEACYLATED N-ACETYL-DL-METHIONINE

    Institute of Scientific and Technical Information of China (English)

    YAN Xiaomin; ZHAO Lin; SHAO Jianhui; TAN Xin; SONG Zhengxiao

    2004-01-01

    N-acetyl-D-methionine, NaAc and the remains of N-acetyl-L-methionine dramatically affect the purification of L-methionine when purified from the mixture of enzymatically deacylated N-acetyl-DL-methionine, leading to a low yield conventionally. Here, this paper reports a successful separation and purification of both L-methionine and N-acetyl-D-methionine by an H ion-exchange column. The pH, L-Met concentration and the ratio between the content of sodium cation and the ion-exchange capacity were optimized to obtain the maximum yield. Experimental results indicate that, under the optimized conditions, the yields of L-methionine and N-acetyl-D-methionine can reach as high as 85% and 75%, respectively.

  3. Inhibition of N-acetylneuraminate lyase by N-acetyl-4-oxo-D-neuraminic acid.

    Science.gov (United States)

    Gross, H J; Brossmer, R

    1988-05-09

    We show that the 4-oxo analogue of N-acetyl-D-neuraminic acid strongly inhibits N-acetylneuraminate lyase (NeuAc aldolase, EC 4.1.3.3) from Clostridum perfringens (Ki = 0.025 mM) and Escherichia coli (Ki = 0.15 mM). In each case the inhibition was competitive. N-Acetyl-D-neuraminic acid; N-Acetylneuraminate lyase; N-Acetyl-D-neuraminic acid analog; 5-Acetamido-3,5-dideoxy-beta-D-manno-non-2,4-diulosonic acid; 2-Deoxy-2,3-didehydro-N-acetyl-4-oxo-neuraminic acid; Competitive inhibitor.

  4. Antioxidant activity of N-acetyl-glucosamine based thiazolidine derivative

    Institute of Scientific and Technical Information of China (English)

    Li Chunlei; Yang Yan; Han Baoqin; Liu Wanshun

    2007-01-01

    N-acetyl-glucosamine,the monomer of chitin,was cyclo-condensed with L-cysteine to prepare thiazolidine derivative:2-N-acetyl-glucosamine-thiazolidine-4(R)-carboxylic acid(GlcNAcCys).The stability of GlcNAcCys was evaluated by high performance liquid chromatography(HPLC)measurement.The results showed that GlcNAcCys Was more stable than other TCA derivatives,especially in alkaline condition.The direct in vitro antioxidative properties of GlcNAcCys were investigated by using UV radiation-induced lipid peroxidation(LPO)in mitochondria and nuclei and.OH-induced LPO in red blood cell (RBC)ghosts models.UV radiation caused dose-dependent LPO in both mitochondria and nuclei,this effect Was catalvzed by addition of Fd2+ while prevented by co-incubation with GlcNAcCys.When nuclei and mitochondria Was treated with 100μl,300μl,500μl of GlcNAcCys and co-incubated at 37℃ for 30min,LPO was decreased to 96%,72%,68%in nuclei and 95%,72%,68% in mitochondria when compared to the UV radiation group respectively.Hydroxyl radicals(.OH)generated by Fenton reaction induced LPO in RBC ghosts.Pretreatment of RBC ghosts with GlcNAcCys could induce antioxidant RBC ghosts and inhibit concentration-dependent malondialdehyde(MDA)formation in antioxidant RBC ghosts.Its inhibition percent Was 14%,35%,36%,42%at 10,20,30,40ms/ml respectively.In a conclusion,the data suggest that GlcNAcCys has antioxidant ability and can significantly inhibit lipid peroxidation in biological samples tested in vitro.

  5. The role of glutathione S-transferase M1 and T1 gene polymorphisms and fruit and vegetable consumption in antioxidant parameters in healthy subjects.

    Science.gov (United States)

    Yuan, Lin-Hong; Meng, Li-Ping; Ma, Wei-Wei; Li, Sheng; Feng, Jin-Fang; Yu, Huan-Ling; Xiao, Rong

    2012-03-01

    The correlation of glutathione S-transferase (GST) M1/T1 genetic polymorphisms with oxidative stress-related chronic diseases was proved recently. The aim of the present study was to investigate the association of GSTM1/T1 genetic polymorphisms with antioxidant biomarkers and consumption of fruits and vegetables (F&V) in healthy subjects. In this study, for conducting a 3 d dietary survey, 190 healthy adults were recruited. After DNA extraction, a multiple PCR method was used for GSTM1/T1 genotyping. A spectrophotometer method was applied for the determination of plasma total antioxidant capacity (T-AOC), vitamin C level and erythrocyte GST enzyme activity. A general linear model was used to compare the mean values of antioxidant parameters for different GSTM1/T1 genotypes and consumption of F&V. Polymorphisms of GSTM1/T1 had no effects on plasma T-AOC and vitamin C levels. Deletion of the GSTM1 gene decreased the erythrocyte GST activity. There was correlation between plasma T-AOC and consumption of F&V in the GSTM1⁻ or GSTT1⁺ subjects. A similar pattern was evident for erythrocyte GST activity in the GSTM1⁻ subjects. No association was found among consumption of F&V and GSTM1/T1 genotypes and plasma vitamin C level. Different consumption of F&V had no impact on plasma T-AOC and vitamin C levels in the GSTM1⁻/GSTT1⁺ or GSTM1⁻/GSTT1⁻ subjects. The erythrocyte GST activity was more sensitive to consumption of F&V in the individuals with the GSTM1⁻/GSTT1⁺ genotype. Association was found among GSTM1/T1 genotypes, antioxidant parameters and consumption of F&V. Large-scale and multiple ethnic studies are needed to further evaluate the relationship.

  6. N-acetyl cysteine therapy in acute viral hepatitis

    Institute of Scientific and Technical Information of China (English)

    Huseyin Gunduz; Oguz Karabay; Ali Tamer; Resat Ozaras; Ali Mert; Omer Fehmi Tabak

    2003-01-01

    AIM: To investigate the effect of N-acetyl cysteine (NAC)on acute viral hepatitis (AVH).METHODS: We administered 200 mg oral NAC three times daily (600 mg/day) to the study group and placebo capsules to the control group. All patients were hospitalized and diagnosed as AVH. Blood total and direct bilirubin, ALT, AST,alkaline phosphatese, albumin and globulin levels of each patient were measured twice weekly until total bilirubin level dropped under 2 mg/dl, ALT level under 100 U/L, follow up was continued and then the patients were discharged.RESULTS: A total of 41(13 female and 28 male) AVH patients were included in our study. The period for normalization of ALT and total bilirubin in the study group was 19.7±6.9 days and 13.7±8.5 days respectively. In the control group it was 20.4±6.5 days and 16.9±7.8 days respectively (P>0.05).CONCLUSION: NAC administration effected neither the time necessary for normalization of ALT and total bilirubin values nor duration of hospitalization, so we could not suggest NAC for the treatment of icteric AVH cases. However, our results have shown that this drug is not harmful to patients with AVH.

  7. Effect of N-acetyl cysteine on Helicobacter pylori.

    Science.gov (United States)

    Gurbuz, Ahmet Kemal; Ozel, A Melih; Ozturk, Ramazan; Yildirim, Sukru; Yazgan, Yusuf; Demirturk, Levent

    2005-11-01

    Use of mucolytic agents that result in reduced mucous viscosity of the gastric mucous has been suggested to have an additive effect in curing Helicobacter pylori infection. Seventy Hpylori-positive patients were given either eradication treatment consisting of 500 mg clarithromycin bid and 30 mg lansoprazole bid for 10 days plus 10 mL (400 mg) N-acetyl cysteine (NAC) liquid tid (AC group) or eradication treatment only (control group). The results were compared 1 month after the completion of the treatment. Fifty-eight patients were available for statistical analysis. Of the 28 patients in the AC group, 14 (50.0%) eradicated the infection after treatment, whereas only 7 of 30 (23.3%) patients in the control group had negative results. The difference between the AC group and the control group was statistically significant (P = 0.034). In both groups, there was no difference in the number of smokers and in the eradication rates between smokers and nonsmokers. Eradication treatment with or without NAC caused no significant side effects in either group. Our findings suggest that NAC has an additive effect on the eradication rates of H pylori obtained with dual therapy with lansoprazole and clarithromycin. NAC does not have any known activity against H pylori, but it may improve the delivery of antibiotics at the site of infection due to its ability to reduce the thickness of the mucus.

  8. The effect of N-acetyl cysteine on laryngopharyngeal reflux.

    Directory of Open Access Journals (Sweden)

    Payman Dabirmoghaddam

    2013-11-01

    Full Text Available Laryngopharyngeal reflux (LPR is a variant of gastroesophageal reflux disease (GERD in which the stomach contents go up into the pharynx and then down into the larynx. LPR causes a wide spectrum of manifestations mainly related to the upper and the lower respiratory system such as laryngitis, asthma, chronic obstructive pulmonary disease, cough, hoarseness, postnasal drip disease, sinusitis, otitis media, recurrent pneumonia, laryngeal cancer and etc. The object of this study was to examine the effect of N-acetyl Cysteine (NAC with and without Omeprazole on laryngitis and LPR. Ninety patients with laryngitis or its symptoms were referred and randomly assigned into three groups. The first group was treated by Omeprazole and NAC. The second group was treated by Omeprazole and placebo and the last group was treated by NAC and placebo. Duration of treatment was 3 months and all patients were evaluated at the beginning of study, one month and three month after treatment of sign and symptoms, based on reflux symptom index (RSI and reflex finding score (RFS. Based on the results of this study, despite therapeutic efficacy of all treatment protocols, the RSI before and after 3 months treatment had significant difference in (NAS+ Omeprazole and (Omeprazole+ placebo group (P<0.001 in the first group, P<0.001 in the second group and P=0.35 in the third group. Whereas RFS before and after 3 month treatment had significant difference in all groups. (P<0.001 in each group in comparison with itself but this results had not significant difference after 1 month treatment. Our results showed that the combination therapy with Omeprazole and NAC treatment had the most effect on both subjective and objective questionnaire at least after 3 months treatment. Based on the results of the present study, it seems that the use objective tools are more accurate than subjective tools in evaluation of therapeutic effects in patients with GERD-related laryngitis.

  9. 40 CFR 180.1089 - Poly-N-acetyl-D-glucosamine; exemption from the requirement of tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Poly-N-acetyl-D-glucosamine; exemption... FOOD Exemptions From Tolerances § 180.1089 Poly-N-acetyl-D-glucosamine; exemption from the requirement... biochemical nematicide poly-N-acetyl-D-glucosamine on a variety of agricultural crops....

  10. Catalytic dehalogenation of N-acetyl-L-4-chloro- and N-acetyl-L-4-iodophenylalanine amide in the presence of deuterium

    Energy Technology Data Exchange (ETDEWEB)

    Oehlke, J.; Bienert, M.; Niedrich, H.; Zoepfl, H.-J.; Franke, P.

    1986-09-01

    As a model for the tritium labeling of peptides, the catalytic dehalogenation of N-Acetyl-L-4-chloro- and N-Acetyl-L-4-iodo-phenylalanine amide was investigated in the presence of deuterium, using different reaction conditions. A catalyst-mediated transfer of the solvent-hydrogen to the substrate was found to be the most probable reason for the exchange of halogen by hydrogen instead of deuterium. This unwanted transfer was most intensive in the presence of water. An incorporation of additional deuterium besides the 4-position of phenylalanine takes place simultaneously with the dehalogenation especially of the chloro derivative.

  11. N-acetyl-β-D-glucosaminidase activity in feral Carcinus maenas exposed to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Mesquita, Sofia Raquel, E-mail: smesquita@ciimar.up.pt [Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, P 4050-123 Porto (Portugal); ICBAS – Institute of Biomedical Sciences Abel Salazar, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto (Portugal); Ergen, Şeyda Fikirdeşici [Faculty of Science, Ankara University, Department of Biology, 06100 Tandogan, Ankara (Turkey); Rodrigues, Aurélie Pinto [Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, P 4050-123 Porto (Portugal); ICBAS – Institute of Biomedical Sciences Abel Salazar, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto (Portugal); Oliva-Teles, M. Teresa; Delerue-Matos, Cristina [REQUIMTE, School of Engineering, Polytechnic Institute of Porto, Rua Dr. António Bernardino de Almeida 431, 4200-072 Porto (Portugal); Guimarães, Laura, E-mail: lguimaraes@ciimar.up.pt [Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, P 4050-123 Porto (Portugal)

    2015-02-15

    Highlights: • Effects of Cd on NAGase activity of crabs from low impacted and polluted sites. • Inhibition of epidermal NAGase by Cd in crabs from both sites. • Inhibition of NAGase in digestive gland only in crabs from low impacted site. • Glutathione role in enhanced tolerance to Cd of crabs from polluted site. - Abstract: Cadmium is a priority hazardous substance, persistent in the aquatic environment, with the capacity to interfere with crustacean moulting. Moulting is a vital process dictating crustacean growth, reproduction and metamorphosis. However, for many organisms, moult disruption is difficult to evaluate in the short term, what limits its inclusion in monitoring programmes. N-acetyl-β-D-glucosaminidase (NAGase) is an enzyme acting in the final steps of the endocrine-regulated moulting cascade, allowing for the cast off of the old exoskeleton, with potential interest as a biomarker of moult disruption. This study investigated responses to waterborne cadmium of NAGase activity of Carcinus maenas originating from estuaries with different histories of anthropogenic contamination: a low impacted and a moderately polluted one. Crabs from both sites were individually exposed for seven days to cadmium concentrations ranging from 1.3 to 2000 μg/L. At the end of the assays, NAGase activity was assessed in the epidermis and digestive gland. Detoxification, antioxidant, energy production, and oxidative stress biomarkers implicated in cadmium metabolism and tolerance were also assessed to better understand differential NAGase responses: activity of glutathione S-transferases (GST), glutathione peroxidase (GPx) glutathione reductase (GR), levels of total glutathiones (TG), lipid peroxidation (LPO), lactate dehydrogenase (LDH), and NADP{sup +}-dependent isocitrate dehydrogenase (IDH). Animals from the moderately polluted estuary had lower NAGase activity both in the epidermis and digestive gland than in the low impacted site. NAGase activity in the

  12. Calix[4]arene-Based Enantioselective Fluorescent Sensors for the Recognition of N-Acetyl-aspartate

    Institute of Scientific and Technical Information of China (English)

    QING Guang-Yan; CHEN Zhi-Hong; WANG Feng; YANG Xi; MENG Ling-Zhi; HE Yong-Bing

    2008-01-01

    Two-armed chiral anion receptors (1 and 2), calix[4]arenes bearing dansyl fluorophore and (1R,2R)- or(1S,2S)-1,2-diphenylethylenediamine binding sites, were prepared and examined for their chiral amino acid anion binding abilities by the fluorescence spectra in dimethylsulfoxide (DMSO). The results of non-linear curve fitting indicate that 1 or 2 forms a 1 : 1 stoichiometry complex with N-acetyl-L-or D-aspartate by multiple hydrogen bonding interactions, exhibiting good enantioselective fluorescent recognition for the enantiomers of N-acetyl-as-partate, [receptor 1: Kass(D)/Kass(L)=6.74; receptor 2: Kass(L)/Kass(D)=6.48]. The clear fluorescent response difference indicates that receptors 1 and 2 could be used as a fluorescent chemosensor for N-Acetyl-aspartate.

  13. Acetylated α-Tubulin Regulated by N-Acetyl-Seryl-Aspartyl-Lysyl-Proline(Ac-SDKP) Exerts the Anti-fibrotic Effect in Rat Lung Fibrosis Induced by Silica.

    Science.gov (United States)

    Xiaojun, Wang; Yan, Liu; Hong, Xu; Xianghong, Zhang; Shifeng, Li; Dingjie, Xu; Xuemin, Gao; Lijuan, Zhang; Bonan, Zhang; Zhongqiu, Wei; Ruimin, Wang; Brann, Darrell; Fang, Yang

    2016-08-31

    Silicosis is the most serious occupational disease in China. The objective of this study was to screen various proteins related to mechanisms of the pathogenesis of silicosis underlying the anti-fibrotic effect of N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) using proteomic profile analysis. We also aimed to explore a potential mechanism of acetylated α-tubulin (α-Ac-Tub) regulation by Ac-SDKP. Two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF/TOF MS) were used to assess the different protein expression profiles between control and silicosis rats treated with or without Ac-SDKP. Twenty-nine proteins were identified to be potentially involved in the progression of silicosis and the anti-fibrotic effect of Ac-SDKP. Our current study finds that 1) the lost expression of Ac-Tub-α may be a new mechanism in rat silicosis; 2) treatment of silicotic rats with N-acetyl-Seryl-Aspartyl-Lysyl-Proline (Ac-SDKP) inhibits myofibroblast differentiation and collagen deposition accompanied by stabilizing the expression of α-Ac-Tub in vivo and in vitro, which is related with deacetylase family member 6 (HDAC6) and α-tubulin acetyl transferase (α-TAT1). Our data suggest that α-Ac-Tub regulation by Ac-SDKP may potentially be a new anti-fibrosis mechanism.

  14. Micronutrients, N-Acetyl Cysteine, Probiotics and Prebiotics, a Review of Effectiveness in Reducing HIV Progression

    Directory of Open Access Journals (Sweden)

    Ruben Hummelen

    2010-06-01

    Full Text Available Low serum concentrations of micronutrients, intestinal abnormalities, and an inflammatory state have been associated with HIV progression. These may be ameliorated by micronutrients, N-acetyl cysteine, probiotics, and prebiotics. This review aims to integrate the evidence from clinical trials of these interventions on the progression of HIV. Vitamin B, C, E, and folic acid have been shown to delay the progression of HIV. Supplementation with selenium, N-acetyl cysteine, probiotics, and prebiotics has considerable potential, but the evidence needs to be further substantiated. Vitamin A, iron, and zinc have been associated with adverse effects and caution is warranted for their use.

  15. Micronutrients, N-Acetyl Cysteine, Probiotics and Prebiotics, a Review of Effectiveness in Reducing HIV Progression

    Science.gov (United States)

    Hummelen, Ruben; Hemsworth, Jaimie; Reid, Gregor

    2010-01-01

    Low serum concentrations of micronutrients, intestinal abnormalities, and an inflammatory state have been associated with HIV progression. These may be ameliorated by micronutrients, N-acetyl cysteine, probiotics, and prebiotics. This review aims to integrate the evidence from clinical trials of these interventions on the progression of HIV. Vitamin B, C, E, and folic acid have been shown to delay the progression of HIV. Supplementation with selenium, N-acetyl cysteine, probiotics, and prebiotics has considerable potential, but the evidence needs to be further substantiated. Vitamin A, iron, and zinc have been associated with adverse effects and caution is warranted for their use. PMID:22254046

  16. On the path to glycan conformer identification: Gas-phase study of the anomers of methyl glycosides of N-acetyl-d-glucosamine and N-acetyl-d-galactosamine

    NARCIS (Netherlands)

    Contreras, C. S.; Polfer, N. C.; Oomens, J.; Steill, J. D.; Bendiak, B.; Eyler, J. R.

    2012-01-01

    The methyl glycosides of N-acetyl-d-glucosamine (d-GlcNAc) and N-acetyl-d-galactosamine (d-GalNAc) have been used as model glycan analogs to study the effects of lithium cation binding on glycan structure in gas-phase experiments. Infrared multiple photon dissociation (IRMPD) spectra for the two Li+

  17. On the path to glycan conformer identification: Gas-phase study of the anomers of methyl glycosides of N-acetyl-D-glucosamine and N-acetyl-D-galactosamine

    NARCIS (Netherlands)

    C.S. Contreras; N.C. Polfer; J. Oomens; J.D. Steill; B. Bendiak; J.R. Eyler

    2012-01-01

    The methyl glycosides of N-acetyl-d-glucosamine (d-GlcNAc) and N-acetyl-d-galactosamine (d-GalNAc) have been used as model glycan analogs to study the effects of lithium cation binding on glycan structure in gas-phase experiments. Infrared multiple photon dissociation (IRMPD) spectra for the two Li+

  18. Micronutrients, N-Acetyl Cysteine, Probiotics and Prebiotics, A Review of Effectiveness in Reducing HIV Progression

    NARCIS (Netherlands)

    R.B.S. Hummelen (Ruben); J. Hemsworth (Jaimie); G.K. Reid (Gregor)

    2010-01-01

    textabstractLow serum concentrations of micronutrients, intestinal abnormalities, and an inflammatory state have been associated with HIV progression. These may be ameliorated by micronutrients, N-acetyl cysteine, probiotics, and prebiotics. This review aims to integrate the evidence from clinical t

  19. The effect of N-acetyl-L-cysteine on the viscosity of ileal neobladder mucus.

    NARCIS (Netherlands)

    Schrier, B.P.; Lichtendonk, W.J.; Witjes, J.A.

    2002-01-01

    N-acetyl-L-cysteine (NAC) proved to be an effective mucolytic in pulmonary secretions. Our goal was to investigate the in vitro effect of NAC on viscosity of ileal neobladder mucus. The urine of a patient with an ileal neobladder was collected during the first 7 days postoperatively and stored in a

  20. Neurone-specific enolase and N-acetyl-aspartate as potential peripheral markers of ischaemic stroke

    NARCIS (Netherlands)

    Stevens, H; Jakobs, C; de Jager, AEJ; Cunningham, RT; Korf, J

    1999-01-01

    Background After stroke, brain-specific proteins (including neurone-specific enolase) leak into the blood. The question addressed in the present study was whether N-acetyl-aspartate (amino acid derivative localized in cerebral neurones) could also serve as a peripheral marker of ischaemic damage. N-

  1. Micronutrients, N-Acetyl Cysteine, Probiotics and Prebiotics, A Review of Effectiveness in Reducing HIV Progression

    NARCIS (Netherlands)

    R.B.S. Hummelen (Ruben); J. Hemsworth (Jaimie); G.K. Reid (Gregor)

    2010-01-01

    textabstractLow serum concentrations of micronutrients, intestinal abnormalities, and an inflammatory state have been associated with HIV progression. These may be ameliorated by micronutrients, N-acetyl cysteine, probiotics, and prebiotics. This review aims to integrate the evidence from clinical t

  2. Micronutrients, N-acetyl cysteine, probiotics and prebiotics, a review of effectiveness in reducing HIV progression

    NARCIS (Netherlands)

    R.B.S. Hummelen (Ruben); J. Hemsworth (Jaimie); G. Reid (Gregor)

    2010-01-01

    textabstractLow serum concentrations of micronutrients, intestinal abnormalities, and an inflammatory state have been associated with HIV progression. These may be ameliorated by micronutrients, N-acetyl cysteine, probiotics, and prebiotics. This review aims to integrate the evidence from clinical t

  3. The effect of N-acetyl-L-cysteine on the viscosity of ileal neobladder mucus.

    NARCIS (Netherlands)

    Schrier, B.P.; Lichtendonk, W.J.; Witjes, J.A.

    2002-01-01

    N-acetyl-L-cysteine (NAC) proved to be an effective mucolytic in pulmonary secretions. Our goal was to investigate the in vitro effect of NAC on viscosity of ileal neobladder mucus. The urine of a patient with an ileal neobladder was collected during the first 7 days postoperatively and stored in a

  4. Micronutrients, N-Acetyl Cysteine, Probiotics and Prebiotics, A Review of Effectiveness in Reducing HIV Progression

    NARCIS (Netherlands)

    R.B.S. Hummelen (Ruben); J. Hemsworth (Jaimie); G.K. Reid (Gregor)

    2010-01-01

    textabstractLow serum concentrations of micronutrients, intestinal abnormalities, and an inflammatory state have been associated with HIV progression. These may be ameliorated by micronutrients, N-acetyl cysteine, probiotics, and prebiotics. This review aims to integrate the evidence from clinical

  5. Micronutrients, N-acetyl cysteine, probiotics and prebiotics, a review of effectiveness in reducing HIV progression

    NARCIS (Netherlands)

    R.B.S. Hummelen (Ruben); J. Hemsworth (Jaimie); G. Reid (Gregor)

    2010-01-01

    textabstractLow serum concentrations of micronutrients, intestinal abnormalities, and an inflammatory state have been associated with HIV progression. These may be ameliorated by micronutrients, N-acetyl cysteine, probiotics, and prebiotics. This review aims to integrate the evidence from clinical

  6. Acetaminophen analog N-acetyl-m-aminophenol, but not its reactive metabolite, N-acetyl-p-benzoquinone imine induces CYP3A activity via inhibition of protein degradation.

    Science.gov (United States)

    Santoh, Masataka; Sanoh, Seigo; Ohtsuki, Yuya; Ejiri, Yoko; Kotake, Yaichiro; Ohta, Shigeru

    2017-05-06

    Cytochrome P450 (CYP) 3A subfamily members are known to metabolize various types of drugs, highlighting the importance of understanding drug-drug interactions (DDI) depending on CYP3A induction or inhibition. While transcriptional regulation of CYP3A members is widely understood, post-translational regulation needs to be elucidated. We previously reported that acetaminophen (APAP) induces CYP3A activity via inhibition of protein degradation and proposed a novel DDI concept. N-Acetyl-p-benzoquinone imine (NAPQI), the reactive metabolite of APAP formed by CYP, is known to cause adverse events related to depletion of intracellular reduced glutathione (GSH). We aimed to inspect whether NAPQI rather than APAP itself could cause the inhibitory effects on protein degradation. We found that N-acetyl-l-cysteine, the precursor of GSH, and 1-aminobenzotriazole, a nonselective CYP inhibitor, had no effect on CYP3A1/23 protein levels affected by APAP. Thus, we used APAP analogs to test CYP3A1/23 mRNA levels, protein levels, and CYP3A activity. We found N-acetyl-m-aminophenol (AMAP), a regioisomer of APAP, has the same inhibitory effects of CYP3A1/23 protein degradation, while p-acetamidobenzoic acid (PAcBA), a carboxy-substituted form of APAP, shows no inhibitory effects. AMAP and PAcBA cannot be oxidized to quinone imine forms such as NAPQI, so the inhibitory effects could depend on the specific chemical structure of APAP. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Glutathione transferases.

    Science.gov (United States)

    Dixon, David P; Edwards, Robert

    2010-01-01

    The 55 Arabidopsis glutathione transferases (GSTs) are, with one microsomal exception, a monophyletic group of soluble enzymes that can be divided into phi, tau, theta, zeta, lambda, dehydroascorbate reductase (DHAR) and TCHQD classes. The populous phi and tau classes are often highly stress inducible and regularly crop up in proteomic and transcriptomic studies. Despite much study on their xenobiotic-detoxifying activities their natural roles are unclear, although roles in defence-related secondary metabolism are likely. The smaller DHAR and lambda classes are likely glutathione-dependent reductases, the zeta class functions in tyrosine catabolism and the theta class has a putative role in detoxifying oxidised lipids. This review describes the evidence for the functional roles of GSTs and the potential for these enzymes to perform diverse functions that in many cases are not "glutathione transferase" activities. As well as biochemical data, expression data from proteomic and transcriptomic studies are included, along with subcellular localisation experiments and the results of functional genomic studies.

  8. Lifespan extension and increased resistance to environmental stressors by N-Acetyl-L-Cysteine in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Seung-Il Oh

    2015-05-01

    Full Text Available OBJECTIVE: This study was performed to determine the effect of N-acetyl-L-cysteine, a modified sulfur-containing amino acid that acts as a strong cellular antioxidant, on the response to environmental stressors and on aging in C. elegans. METHOD: The survival of worms under oxidative stress conditions induced by paraquat was evaluated with and without in vivo N-acetyl-L-cysteine treatment. The effect of N-acetyl-L-cysteine on the response to other environmental stressors, including heat stress and ultraviolet irradiation (UV, was also monitored. To investigate the effect on aging, we examined changes in lifespan, fertility, and expression of age-related biomarkers in C. elegans after N-acetyl-L-cysteine treatment. RESULTS: Dietary N-acetyl-L-cysteine supplementation significantly increased resistance to oxidative stress, heat stress, and UV irradiation in C. elegans. In addition, N-acetyl-L-cysteine supplementation significantly extended both the mean and maximum lifespan of C. elegans. The mean lifespan was extended by up to 30.5% with 5 mM N-acetyl-L-cysteine treatment, and the maximum lifespan was increased by 8 days. N-acetyl-L-cysteine supplementation also increased the total number of progeny produced and extended the gravid period of C. elegans. The green fluorescent protein reporter assay revealed that expression of the stress-responsive genes, sod-3 and hsp-16.2, increased significantly following N-acetyl-L-cysteine treatment. CONCLUSION: N-acetyl-L-cysteine supplementation confers a longevity phenotype in C. elegans, possibly through increased resistance to environmental stressors.

  9. Sulfation of p-nitrophenyl-N-acetyl-beta-D-galactosaminide with a microsomal fraction from cultured chondrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Habuchi, O.; Conrad, H.E.

    1985-10-25

    Chick embryo chondrocyte microsomes containing intact Golgi vesicles took up 3'-phosphoadenosine-5'-phospho(TVS)sulfate ((TVS)PAPS) in a time- and temperature-dependent, substrate-saturable manner. When (TVS)PAPS and p-nitrophenyl-N-acetyl-beta-D-galactosaminide (pNP-GalNAc) were added to the incubation in the absence of detergent, the microsomes catalyzed the transfer of sulfate from (TVS)PAPS to pNP-GalNAc to form pNP-GalNAc-6-TVSO4. The apparent Km values for PAPS in the uptake and the pNP-GalNAc sulfation reactions were 2 X 10(-7) and 2 X 10(-6) M, respectively. The sulfation of pNP-GalNAc by the microsomal preparation was inhibited by detergent. The microsomal fraction also catalyzed the transfer of sulfate from (TVS)PAPS to oligosaccharides prepared from chondroitin. However, in contrast to the sulfation of pNP-GalNAc, the rate of sulfation of these oligosaccharides was low in the absence of detergent and was markedly stimulated when detergent was added. Sulfation of pNP-GalNAc by the freeze-thawed microsomes was inhibited when the octasaccharide prepared from chondroitin was present in the reaction mixture. As the PAPS that had been internalized in the microsomal vesicles was consumed in the sulfation of pNP-GalNAc, more (TVS)PAPS was taken up and the sulfated pNP-GalNAc was released from the vesicles. These observations suggest that pNP-GalNAc may serve as a model membrane-permeable substrate for study of the 6-sulfo-transferase reaction involved in sulfation of chondroitin sulfate in intact Golgi vesicles.

  10. N-Acetyl cysteine restores viability and function of rat odontoblast-like cells impaired by polymethylmethacrylate dental resin extract.

    Science.gov (United States)

    Yamada, Masahiro; Kojima, Norinaga; Att, Wael; Hori, Norio; Suzuki, Takeo; Ogawa, Takahiro

    2009-01-01

    There is concern that dental-resin materials directly loaded on a prepared tooth adversely affect dental pulp tissue by releasing the resin chemicals through dentinal tubes. This study determined whether self-curing polymethyl methacrylate (PMMA)-based dental resin extract adversely affected the viability and function of odontoblast-like cells and whether the cytotoxicity of this resin, if any, could be eliminated by N-acetyl cysteine, an antioxidant amino acid derivative. Odontoblast-like cells isolated from rat maxillary incisor dental pulp tissue were exposed to a PMMA resin extract with or without N-acetyl cysteine for 1 h and then cultured in osteoblastic media. The percentage of viable cells 24 h after seeding was 20% in cells exposed to the resin extract without N-acetyl cysteine, whereas 45% of cells were viable after exposure to the N-acetyl cysteine-supplemented extract. The cells that had been exposed to the extract showed a strong tendency for apoptosis associated with the increased reactive oxygen species production and decreased intracellular glutathione level, which was improved by the addition of N-acetyl cysteine. N-Acetyl cysteine supplementation almost completely restored the significantly reduced alkaline phosphatase activity and matrix mineralization by the resin extract. These results conclusively demonstrated that exposure of odontoblast-like cells to the resin extract impaired the cell viability and function and, more intriguingly, N-acetyl cysteine supplementation to the extract significantly prevented these toxic effects.

  11. In vivo N-acetyl cysteine reduce hepatocyte death by induced acetaminophen

    Science.gov (United States)

    Lin, Chih-Ju; Li, Feng-Chieh; Wang, Sheng-Shun; Lee, Hsuan-Shu; Dong, Chen-Yuan

    2011-07-01

    Acetaminophen (APAP) is the famous drug in global, and taking overdose Acetaminophen will intake hepatic cell injure. Desptie substantial progress in our understanding of the mechanism of hepatocellular injury during the last 40 years, many aspects of the pathophysiology are still unknown or controversial.1 In this study, mice are injected APAP overdose to damage hepatocyte. APAP deplete glutathione and ATP of cell, N-Acetyl Cysteine (NAC) plays an important role to protect hepatocytes be injury. N-Acetyl Cysteine provides mitochondrial to produce glutathione to release drug effect hepatocyte. By 6-carboxyfluorescein diacetate (6-CFDA) metabolism in vivo, glutathione keep depleting to observe the hepatocyte morphology in time. Without NAC, cell necrosis increase to plasma membrane damage to release 6-CFDA, that's rupture. After 6-CFDA injection, fluorescence will be retained in hepatocyte. For cell retain with NAC and without NAC are almost the same. With NAC, the number of cell rupture decreases about 75%.

  12. Kinetics of Mushroom Tyrosinase and Melanogenesis Inhibition by N-Acetyl-pentapeptides

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    Ching-Yi Lien

    2014-01-01

    Full Text Available We investigated the kinetics of 4N-acetyl-pentapeptides, Ac-P1, Ac-P2, Ac-P3, and Ac-P4, regarding inhibition of mushroom tyrosinase activity. The peptides sequences of Ac-P1, Ac-P2, Ac-P3, and Ac-P4 were Ac-RSRFK, Ac-KSRFR, Ac-KSSFR, and Ac-RSRFS, respectively. The 4N-acetyl-pentapeptides were able to reduce the oxidation of L-DOPA by tyrosinase in a dose-dependent manner. Of the 4N-acetyl-pentapeptides, only Ac-P4 exhibited lag time (80 s at a concentration of 0.5 mg/mL. The tyrosinase inhibitory effects of Ac-P4 (IC50 0.29 mg/mL were more effective than those of Ac-P1, Ac-P2, and Ac-P3, in which IC50s were 0.75 mg/mL, 0.78 mg/mL, and 0.81 mg/mL, respectively. Kinetic analysis demonstrated that all 4N-acetyl-pentapeptides were mixed-type tyrosinase inhibitors. Furthermore, 0.1 mg/mL of Ac-P4 exhibited significant melanogenesis inhibition on B16F10 melanoma cells and was more effective than kojic acid. The melanogenesis inhibition of Ac-P4 was dose-dependent and did not induce any cytotoxicity on B16F10 melanoma cells.

  13. Inhibition of mucin glycosylation by aryl-N-acetyl-alpha-galactosaminides in human colon cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Kuan, S.F.; Byrd, J.C.; Basbaum, C.; Kim, Y.S. (Veterans Administration Medical Center, San Francisco, CA (USA))

    1989-11-15

    Specific inhibitors of the glycosylation of O-glycosidically linked glycoproteins have not previously been described. When tested for their effects on mucin glycosylation in a mucin-producing colon cancer cell line, LS174T, benzyl-, phenyl-, and p-nitrophenyl-N-acetyl-alpha-galactosaminide inhibited the formation of fully glycosylated mucin in a dose-dependent manner. Free aryl-oligosaccharides were found in the medium of treated cells labeled with ({sup 3}H)glucosamine, ({sup 3}H)galactose, ({sup 3}H)fucose, ({sup 3}H)mannosamine, or phenyl-alpha-(6-{sup 3}H) N-acetylgalactosamine. UDP-Gal:GalNAc-beta 1,3-galactosyltransferase was inhibited by aryl-N-acetyl-alpha-galactosaminides but not by a number of other aryl-glycosides. Treatment with these inhibitors also causes reversible morphologic changes including formation of intercellular cysts. Aryl-N-acetyl-alpha-galactosaminides can be useful for the structural and functional studies of mucin macromolecules and other O-linked glycoproteins.

  14. Protective Roles of N-acetyl Cysteine and/or Taurine against Sumatriptan-Induced Hepatotoxicity

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    Javad Khalili Fard

    2016-12-01

    Full Text Available Purpose: Triptans are the drug category mostly prescribed for abortive treatment of migraine. Most recent cases of liver toxicity induced by triptans have been described, but the mechanisms of liver toxicity of these medications have not been clear. Methods: In the present study, we obtained LC50 using dose-response curve and investigated cell viability, free radical generation, lipid peroxide production, mitochondrial injury, lysosomal membrane damage and the cellular glutathione level as toxicity markers as well as the beneficial effects of taurine and/or N-acetyl cysteine in the sumatriptan-treated rat parenchymal hepatocytes using accelerated method of cytotoxicity mechanism screening. Results: It was revealed that liver toxicity induced by sumatriptan in in freshly isolated parenchymal hepatocytes is dose-dependent. Sumatriptan caused significant free radical generation followed by lipid peroxide formation, mitochondrial injury as well as lysosomal damage. Moreover, sumatriptan reduced cellular glutathione content. Taurine and N-acetyl cysteine were able to protect hepatocytes against sumatriptan-induced harmful effects. Conclusion: It is concluded that sumatriptan causes oxidative stress in hepatocytes and the decreased hepatocytes glutathione has a key role in the sumatriptan-induced harmful effects. Also, N-acetyl cysteine and/or taurine could be used as treatments in sumatriptan-induced side effects.

  15. [Activity of N-acetyl-β-hexosaminidase and its isoenzymes A and B in cancer].

    Science.gov (United States)

    Choromańska, Barbara; Luto, Magdalena; Szajda, Sławomir Dariusz; Waszkiewicz, Napoleon; Kępka, Alina; Janica, Jacek; Ladny, Jerzy Robert; Dadan, Jacek; Myśliwiec, Piotr; Zwierz, Krzysztof

    2011-11-23

    There were approximately 93,060 deaths from cancers in Poland in 2008, and about 105,000 are predicted for the year 2025. Early detection of cancer is a major problem throughout the world, which is why many researchers are still looking for specific and sensitive markers of malignant tumors. Our work is a review of recent publications on activity of N-acetyl-β-D-hexosaminidase (HEX) and its isoenzymes A (HEX A) and B (HEX B) as potential markers of malignant tumors. HEX is the most active of the lysosomal exoglycosidases, taking part in degradation of glycoconjugates (glycoproteins, glycolipids, proteoglycans). HEX cleaves N-acetyl-D-glucosamine and N-acetyl-D-galactosamine from non-reducing ends of oligosaccharide chains of glycoproteins, glycolipids and glycosaminoglycans. The activity of HEX, and its isoenzymes A (HEX A) and B (HEX B), was determined by spectrophotometric and isoelectric focusing methods. There was a statistically significant increase in activity of HEX in tumors of the kidney, pancreas, thyroid, colon, ovary, brain, salivary gland, stomach and larynx, which suggests potential applicability of HEX and its isoenzymes in cancer diagnosis.

  16. N-acetyl-β-hexosaminidase in chronic tonsillitis and tonsillar hypertrophy.

    Science.gov (United States)

    Zagor, Mariola; Minarowska, Alina; Knaś, Małgorzata; Krajewska, Katarzyna; Niemcunowicz-Janica, Anna; Marciniak, Justyna; Bierć, Marcin; Zaniewska, Agnieszka; Minarowski, Lukasz; Jackowska, Anna; Jackowski, Tomasz; Zwierz, Krzysztof; Szajda, Sławomir

    2013-01-01

    The concentration and specific activity of N-acetyl-β-hexosaminidase (HEX) in palatine tonsils with chronic tonsillitis and tonsillar hypertrophy give insight in tonsillar tissue remodeling and constitute a potential marker for diagnosis and treatment of chronic tonsillitis and tonsillar hypertrophy. Determining the concentration and specific activity of N-acetyl-β-hexosaminidase in palatine tonsils with hypertrophy and chronic tonsillitis. HEX activity was analyzed by the method of Marciniak et al. with p-nitrophenyl N-acetyl-β-glucosaminepyranoside as a substrate. The concentration and specific activity of HEX in palatine tonsils in patients with tonsillar hypertrophy and chronic tonsillitis both in childhood and adulthood significantly increase in comparison to healthy individuals. Our data demonstrate the presence of HEX in palatine tonsils and indicate on significant increase of its concentration and specific activity. Based on content and specific HEX activity we suggest that tonsils with hypertrophy and chronic tonsillitis should be treated as identical unit irrespectively of age. Copyright © 2013 Polish Otorhinolaryngology - Head and Neck Surgery Society. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.

  17. Activity of N-acetyl-β-hexosaminidase and its isoenzymes A and B in cancer

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    Barbara Choromańska

    2011-11-01

    Full Text Available There were approximately 93,060 deaths from cancers in Poland in 2008, and about 105,000 are predicted for the year 2025. Early detection of cancer is a major problem throughout the world, which is why many researchers are still looking for specific and sensitive markers of malignant tumors.Our work is a review of recent publications on activity of N-acetyl-β-D-hexosaminidase (HEX and its isoenzymes A (HEX A and B (HEX B as potential markers of malignant tumors. HEX is the most active of the lysosomal exoglycosidases, taking part in degradation of glycoconjugates (glycoproteins, glycolipids, proteoglycans. HEX cleaves N-acetyl-D-glucosamine and N-acetyl-D-galactosamine from non-reducing ends of oligosaccharide chains of glycoproteins, glycolipids and glycosaminoglycans.The activity of HEX, and its isoenzymes A (HEX A and B (HEX B, was determined by spectrophotometric and isoelectric focusing methods. There was a statistically significant increase in activity of HEX in tumors of the kidney, pancreas, thyroid, colon, ovary, brain, salivary gland, stomach and larynx, which suggests potential applicability of HEX and its isoenzymes in cancer diagnosis.

  18. N-acetylation and phosphorylation of Sec complex subunits in the ER membrane

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    Soromani Christina

    2012-12-01

    Full Text Available Abstract Background Covalent modifications of proteins provide a mechanism to control protein function. Here, we have investigated modifications of the heptameric Sec complex which is responsible for post-translational protein import into the endoplasmic reticulum (ER. It consists of the Sec61 complex (Sec61p, Sbh1p, Sss1p which on its own mediates cotranslational protein import into the ER and the Sec63 complex (Sec63p, Sec62p, Sec71p, Sec72p. Little is known about the biogenesis and regulation of individual Sec complex subunits. Results We show that Sbh1p when it is part of the Sec61 complex is phosphorylated on T5 which is flanked by proline residues. The phosphorylation site is conserved in mammalian Sec61ß, but only partially in birds, and not in other vertebrates or unicellular eukaryotes, suggesting convergent evolution. Mutation of T5 to A did not affect the ability of mutant Sbh1p to complement the growth defect in a Δsbh1Δsbh2 strain, and did not result in a hypophosphorylated protein which shows that alternate sites can be used by the T5 kinase. A survey of yeast phosphoproteome data shows that Sbh1p can be phosphorylated on multiple sites which are organized in two patches, one at the N-terminus of its cytosolic domain, the other proximal to the transmembrane domain. Surprisingly, although N-acetylation has been shown to interfere with ER targeting, we found that both Sbh1p and Sec62p are cotranslationally N-acetylated by NatA, and N-acetyl-proteome data indicate that Sec61p is modified by the same enzyme. Mutation of the N-acetylation site, however, did not affect Sec62p function in posttranslational protein import into the ER. Disabling NatA resulted in growth retardation, but not in co- or posttranslational translocation defects or instability of Sec62p or Sbh1p. Conclusions We conclude that N-acetylation of transmembrane and tail-anchored proteins does not interfere with their ER-targeting, and that Sbh1p phosphorylation on T5

  19. Insect glutathione transferases.

    Science.gov (United States)

    Ketterman, Albert J; Saisawang, Chonticha; Wongsantichon, Jantana

    2011-05-01

    This article is an overview of the current knowledge of insect glutathione transferases. Three major topics are discussed: the glutathione transferase contributions to insecticide resistance, the polymorphic nature of the insect glutathione transferase superfamily, and a summary of the current structure-function studies on insect glutathione transferases.

  20. Prevention of enzymatic browning of postharvest longan fruit by N-acetyl-L-cysteine and 4-hexylresorcinol

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    Chiraporn Sodchit

    2008-01-01

    Full Text Available The effects of N-acetyl-L-cysteine and 4-hexylresorcinol on browning inhibition of postharvest longan fruits cv. Daw were studied. The fruits were dipped for 5 min 5, 25, and 45 mM N-acetyl-L-cysteine and 0.01, 0.03 and 0.05% 4- hexylresorcinol, stored at 15+2C and 85 %RH for 6 days. The results showed that N-acetyl-L-cysteine prevented pericarb browning of the fruits better than 4-hexylresorcinol, which resulted in better color values but did not significantly differ (p>0.05 among the concentrations used. Besides, the longan fruits treated with N-acetyl-L-cysteine tended to decrease disease incidence and lowered weight loss 2 compared with those treated with 4-hexylresorcinol. Neither browning inhibitor had an effect on the fall off fruits.

  1. Effectiveness of Oral N-acetyl-cystein in Reduction of Pulmonary Complications in Smokers Undergoing Coronary Artery Bypass Surgery

    National Research Council Canada - National Science Library

    SJ Mir Hoseini; MH Abdollahi; H Hoseini; A Halvani; N Rahati Talab; SK Foroozan Nia; H Moshtaghion

    2009-01-01

    .... In this study, the effect of oral N-acetyl-cystein in reduction of severity of hypoxemia and atelectasis in current smokers who smoked more than 10 packs/year and had undergone CABG was evaluated. Methods...

  2. Development of a N-acetyl-β-D-glucosaminidase (NAG) assay on a centrifugal lab-on-a-compact-disc (Lab-CD) platform.

    Science.gov (United States)

    Tanaka, Yoshihide; Okuda, Seira; Sawai, Ayumi; Suzuki, Shigeo

    2012-01-01

    A centrifugal microfluidic platform, which is also known as lab-on-a-compact-disc (Lab-CD), was developed for use as a urinary N-acetyl-β-D-glucosaminidase (NAG) activity assay. In this work, Lab-CD design, centrifugal operations and analytical procedures were established. Automated liquid handling on Lab-CD processes, such as fluid transport, sample metering, mixing, and fluorescence detection are accomplished using a portable Lab-CD system. The linearity of the NAG assay using 4-methylumbelliferyl-N-acetyl-β-D-glucosaminide (4-MU-GlcNAc) was found to be acceptable in the range of 2.5 to 20 U L(-1); the relative standard deviations for the fluorescence intensity of eight samples (7.5 U L(-1)) was 6.4%. Clinical diagnostics is one of the most promising applications for Lab-CD technologies. All the benefits of miniaturization, such as reduced sample requirement, reduced reagent consumption and automation, are realized in this investigation.

  3. Interactions between N-acetyl-L-cysteine protected CdTe quantum dots and doxorubicin through spectroscopic method

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiupei, E-mail: xiupeiyang@163.com [Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, Nanchong 637000 (China); College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637000 (China); Lin, Jia; Liao, Xiulin; Zong, Yingying; Gao, Huanhuan [College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637000 (China)

    2015-06-15

    Highlights: • CdTe quantum dots with the diameter of 3–5 nm were synthesized in aqueous solution. • The modified CdTe quantum dots showed well fluorescence properties. • The interaction between the CdTe quantum dots and doxorubicin (DR) was investigated. - Abstract: N-acetyl-L-cysteine protected cadmium telluride quantum dots with a diameter of 3–5 nm were synthesized in aqueous solution. The interaction between N-acetyl-L-cysteine/cadmium telluride quantum dots and doxorubicin was investigated by ultraviolet–visible absorption and fluorescence spectroscopy at physiological conditions (pH 7.2, 37 °C). The results indicate that electron transfer has occurred between N-acetyl-L-cysteine/cadmium telluride quantum dots and doxorubicin under light illumination. The quantum dots react readily with doxorubicin to form a N-acetyl-L-cysteine/cadmium telluride-quantum dots/doxorubicin complex via electrostatic attraction between the −NH{sub 3}{sup +} moiety of doxorubicin and the −COO{sup −} moiety of N-acetyl-L-cysteine/cadmium telluride quantum dots. The interaction of N-acetyl-L-cysteine/cadmium telluride-quantum dots/doxorubicin complex with bovine serum albumin was studied as well, showing that the complex might induce the conformation change of bovine serum due to changes in microenvironment of bovine serum.

  4. Purification of a N-acetyl-D-galactosamine specific lectin from the orchid Laelia autumnalis.

    Science.gov (United States)

    Zenteno, R; Chávez, R; Portugal, D; Páez, A; Lascurain, R; Zenteno, E

    1995-10-01

    From the pseudobulbs of the orchid L. autumnalis a lectin was purified on immobilized porcine mucin with A + H blood group substance. This lectin is a dimeric glycoprotein of M(r) 12,000 with an Sw,20 of 2.2, showing haemagglutinating activity directed mainly to human A1 desialylated erythrocytes. The lectin possesses sugar specificity for N-acetyl-D-galactosamine and also shows high specificity for glycoproteins containing the T (galactose beta 1,3GA1NAc alpha 1,0 Ser/Thr) or the Tn antigen (GalNAc alpha 1,0 Ser/Thr).

  5. A conformational study of N -acetyl glucosamine derivatives utilizing residual dipolar couplings

    Science.gov (United States)

    Kramer, Markus; Kleinpeter, Erich

    2011-09-01

    The conformational analyses of six non-rigid N-acetyl glucosamine (NAG) derivatives employing residual dipolar couplings (RDCs) and NOEs together with molecular dynamics (MD) simulations are presented. Due to internal dynamics we had to consider different conformer ratios existing in solution. The good quality of the correlation between theoretically and experimentally obtained RDCs show the correctness of the calculated conformers even if the ratios derived from the MD simulations do not exactly meet the experimental data. If possible, the results were compared to former published data and commented.

  6. Interactions of egg yolk phosphatidylcholine with cholesteryl polyethoxy neoglycolipids containing N-acetyl- D-glucosamine

    Science.gov (United States)

    Kemoun, Rachida; Gelhausen, Micaèle; Besson, Françoise; Lafont, Dominique; Buchet, René; Boullanger, Paul; Roux, Bernard

    1999-03-01

    Series of neoglycolipids containing cholesteryl and N-acetyl- D-glucosaminyl groups were synthesized with various ethoxy linkers. Their self aggregations and intermolecular interactions, without and with egg yolk phosphatidylcholine (EYPC), were characterized in dry and hydrated states, by using infrared spectroscopy. The neoglycolipids in the dry state formed intermolecular hydrogen bonds between the CO and N-H or O-H groups of N-acetyl- D-glucosamine (GlcNAc). In the presence of EYPC, these intermolecular interactions were broken and new hydrogen bonds, involving the phosphate group of EYPC and N-H or O-H groups of GlcNAc of neoglycolipid, were formed. The presence of water molecules altered these intermolecular hydrogen bonds. The CO groups of EYPC were not affected by the presence of neoglycolipids, either in hydrated or in dry states, indicating that the GlcNAc polar groups interacted mostly with EYPC phosphate residues. The phase transition-temperature of mixtures of EYPC containing either cholesterol or neoglycolipid were similar, indicating that the cholesteryl group of the neoglycolipid interacted in the same manner as cholesterol with hydrocarbon chains of EYPC. Some structural models of molecular interactions of neoglycolipids were discussed in relation with the molecular recognition of wheat germ agglutinin.

  7. Highly Active Copolymerization of Ethylene and N-Acetyl-O-(ω-Alkenyl-l-Tyrosine Ethyl Esters Catalyzed by Titanium Complex

    Directory of Open Access Journals (Sweden)

    Jing Wang

    2016-03-01

    Full Text Available A series of N-acetyl-O-(ω-alkenyl-l-tyrosine ethyl esters were synthesized by the reaction of vinyl bromides (4-bromo-1-butene, 6-bromo-1-hexene, 8-bromo-1-octene and 10-bromo-1-decene with N-acetyl-l-tyrosine ethyl ester. 1H NMR, elemental analysis, FT-IR, and mass spectra were performed for these N-acetyl-O-(ω-alkenyl-l-tyrosine ethyl esters. The novel titanium complex can catalyze the copolymerization of ethylene and N-acetyl-O-(ω-alkenyl-l-tyrosine ethyl esters efficiently and the highest catalytic activity was up to 6.86 × 104 gP·(molTi−1·h−1. The structures and properties of the obtained copolymers were characterized by FT-IR, (1H13C NMR, GPC, DSC, and water contact angle. The results indicated that the obtained copolymers had a uniformly high average molecular weight of 2.85 × 105 g·mol−1 and a high incorporation ratio of N-acetyl-O-(but-3-enyl-l-tyrosine ethyl ester of 2.65 mol % within the copolymer chain. The units of the comonomer were isolated within the copolymer chains. The insertion of the polar comonomer into a copolymer chain can effectively improve the hydrophilicity of a copolymer.

  8. Estimation of serum glutamic oxaloacetic transaminase, serum glutamic-pyruvic transaminase, gamma-glutamyl transferase and cholesterol levels in prolonged (30 years) daily consumption coffee in people

    OpenAIRE

    J. Sudha Rani; D. S. S. K. Raju

    2016-01-01

    Background: Although prolonged (30years) coffee consumption has been associated with reduced or increased frequency of liver (SGOT, SGPT, GGT) enzymes and cholesterol levels, it is unclear whether the effect is from coffee or caffeine. Methods: A self-administered questionnaire ascertained lifestyle characteristics, including alcohol consumption, cigarette smoking, Diabetes mellitus and Dietary habits. As for drinking habit, examinees were first asked about their current drinking frequency...

  9. Modulation of liver L-γ-glutamyl-L-cysteinylglycine homeostasis by N-acetyl-glucosamine-thiazolidine-4(R)-carboxylic acid in mice.

    Science.gov (United States)

    Liu, Ji; Cai, Wendi; Liu, Wanshun; Han, Baoqin; Chang, Jing; Yang, Yan

    2012-04-01

    The properties of modulating liver L-γ-glutamyl-L-cysteinylglycine (GSH) homeostasis by thiazolidine derivative N-acetyl-glucosamine-thiazolidine-4(R)-carboxylic acid (GlcNAcCys) and the underlying mechanisms were investigated in L-buthionine-[S,R]-sulfoximine (BSO)-induced mice liver GSH depletion model. The data show that BSO (6 mmol/kg body weight; intraperitoneally) significantly decreased liver total sulfhydryl and GSH concentrations when compared with control. When mice were treated with different doses of GlcNAcCys (200, 400, 900 mg/kg body weight; intraperitoneally, respectively), total sulfhydryl and GSH concentrations were significantly increased when measured 6 hours after treatment. The activities of GSH-associated enzymes were also measured. Liver glutathione S-transferase (GST) activities were significantly decreased by BSO compared with the control, and GlcNAcCys significantly increased GST activity. Moreover, reverse-transcriptase polymerase chain reaction data indicated that GlcNAcCys could significantly induce glutamylcysteine ligase catalytic subunit c mRNA transcription. The mRNA levels of transcription factors c-jun and c-fos were increased by BSO administration but were decreased back to normal after the administration of GlcNAcCys. In a conclusion, GlcNAcCys can modulate liver GSH homeostasis, which may be related to its ability to induce glutamylcysteine ligase catalytic subunit transcription. GlcNAcCys has potential hepatoprotective properties by increasing GSH content, increasing GST activity.

  10. N-acetyl-L-cysteine prevents stress-induced desmin aggregation in cellular models of desminopathy.

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    Bertrand-David Segard

    Full Text Available Mutations within the human desmin gene are responsible for a subcategory of myofibrillar myopathies called desminopathies. However, a single inherited mutation can produce different phenotypes within a family, suggesting that environmental factors influence disease states. Although several mouse models have been used to investigate organ-specific desminopathies, a more general mechanistic perspective is required to advance our knowledge toward patient treatment. To improve our understanding of disease pathology, we have developed cellular models to observe desmin behaviour in early stages of disease pathology, e.g., upon formation of cytoplasmic desmin aggregates, within an isogenic background. We cloned the wildtype and three mutant desmin cDNAs using a Tet-On Advanced® expression system in C2C12 cells. Mutations were selected based on positioning within desmin and capacity to form aggregates in transient experiments, as follows: DesS46Y (head domain; low aggregation, DesD399Y (central rod domain; high aggregation, and DesS460I (tail domain; moderate aggregation. Introduction of these proteins into a C2C12 background permitted us to compare between desmin variants as well as to determine the role of external stress on aggregation. Three different types of stress, likely encountered during muscle activity, were introduced to the cell models-thermal (heat shock, redox-associated (H2O2 and cadmium chloride, and mechanical (stretching stresses-after which aggregation was measured. Cells containing variant DesD399Y were more sensitive to stress, leading to marked cytoplasmic perinuclear aggregations. We then evaluated the capacity of biochemical compounds to prevent this aggregation, applying dexamethasone (an inducer of heat shock proteins, fisetin or N-acetyl-L-cysteine (antioxidants before stress induction. Interestingly, N-acetyl-L-cysteine pre-treatment prevented DesD399Y aggregation during most stress. N-acetyl-L-cysteine has recently been

  11. Chitinase but N-acetyl-β-D-glucosaminidase production correlates to the biomass decline in Penicillium and Aspergillus species.

    Science.gov (United States)

    Pusztahelyi, Tünde; Pócsi, István

    2014-06-01

    Hydrolytic enzyme production is typical of the autolysis in filamentous fungi; however, less attention has been given to the physiological role of the enzymes. Here, the aim was to investigate the possible relation of the chitinolytic enzymes to the changes in the biomass in some filamentous fungi of high importance for pharmaceutical or food industry. In Penicillium and Aspergillus filamentous fungi, which showed different characteristics in submerged cultures, the growth and biomass decline rates were calculated and correlated to the chitinase and N-acetyl-β-D-glucosaminidase enzyme productions. Correlation was found between the biomass decrease rate and the chitinase level at the stationary growth phase; while chitinase production covariates negatively with N-acetyl-β-D-glucosaminidase activities. The chitinase production and the intensive autolysis hindered the production of N-acetyl-β-D-glucosaminidase and, therefore, could hinder the cell death in the cultures.

  12. Metabolomic Analysis of Blood Plasma after Oral Administration of N-acetyl-d-Glucosamine in Dogs

    Directory of Open Access Journals (Sweden)

    Tomohiro Osaki

    2015-08-01

    Full Text Available N-acetyl-d-glucosamine (GlcNAc is a monosaccharide that polymerizes linearly through (1,4-β-linkages. GlcNAc is the monomeric unit of the polymer chitin. GlcNAc is a basic component of hyaluronic acid and keratin sulfate found on the cell surface. The aim of this study was to examine amino acid metabolism after oral GlcNAc administration in dogs. Results showed that plasma levels of ectoine were significantly higher after oral administration of GlcNAc than prior to administration (p < 0.001. To our knowledge, there have been no reports of increased ectoine concentrations in the plasma. The mechanism by which GlcNAc administration leads to increased ectoine plasma concentration remains unclear; future studies are required to clarify this mechanism.

  13. Synthesis, crystal and supramolecular structure of rac-N-acetyl-2- thiohydantoin-asparagine

    Directory of Open Access Journals (Sweden)

    Gerzon E. Delgado

    2014-05-01

    Full Text Available The title compound, C7H9N3O3S, also known as rac-N-acetyl-5-propionamide-2-thioxo-imidazolidin-4-one, crystallize in the monoclinic system with space group P21/n (Nº14, Z=4, and unit cell parameters a= 9.338 (7 Å, b= 7.545 (5 Å, c= 13.212 (10 Å, E= 97.10 (2°, V= 932.8 (12 Å3. The acetyl group and the mean plane of the ureido group form an angle of 81.0 (2°. In the supramolecular structure, the molecules are joined by N--H···O hydrogen bonds into cyclic structures with graph-set R2 2(14 and R2 2(16, forming a three-dimensional network.

  14. Expanding the phenotype of hawkinsinuria: new insights from response to N-acetyl-L-cysteine.

    Science.gov (United States)

    Gomez-Ospina, Natalia; Scott, Anna I; Oh, Gia J; Potter, Donald; Goel, Veena V; Destino, Lauren; Baugh, Nancy; Enns, Gregory M; Niemi, Anna-Kaisa; Cowan, Tina M

    2016-11-01

    Hawkinsinuria is a rare disorder of tyrosine metabolism that can manifest with metabolic acidosis and growth arrest around the time of weaning off breast milk, typically followed by spontaneous resolution of symptoms around 1 year of age. The urinary metabolites hawkinsin, quinolacetic acid, and pyroglutamic acid can aid in identifying this condition, although their relationship to the clinical manifestations is not known. Herein we describe clinical and laboratory findings in two fraternal twins with hawkinsinuria who presented with failure to thrive and metabolic acidosis. Close clinical follow-up and laboratory testing revealed previously unrecognized hypoglycemia, hypophosphatemia, combined hyperlipidemia, and anemia, along with the characteristic urinary metabolites, including massive pyroglutamic aciduria. Treatment with N-acetyl-L-cysteine (NAC) restored normal growth and normalized or improved most biochemical parameters. The dramatic response to NAC therapy supports the idea that glutathione depletion plays a key role in the pathogenesis of hawkinsinuria.

  15. Effect of shock wave reapplication on urinary n-acetyl-beta-glucosaminidase in canine kidney

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    Marco A.Q.R. Fortes

    2004-04-01

    Full Text Available OBJECTIVE: Renal tubular damage can be assessed with the aid of urinary dosing of N-acetyl-beta-glucosaminidase (NAG and it is possible to demonstrate a significant correlation between shock wave and damage to renal parenchyma. The objective of this study was to assess the effect of shock wave reapplication over urinary NAG in canine kidney. MATERIALS AND METHODS: The authors submitted 10 crossbred dogs to 2 applications of 2000 shock waves in a 24-hour interval in order to assess urinary NAG values after 12, 24, 36 and 48 hours. RESULTS: Twelve hours following the first shockwave application there was an increase in NAG of 6.47 ± 5.44 u/g creatinine (p 0.05. CONCLUSION: Shock wave reapplication with a 24-hour interval did not cause any increase in urinary NAG.

  16. Effects of Partially N-acetylated Chitosans to Elicit Resistance Reaction on Brassica napus L.

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xue-kun; TANG Zhang-lin; CHEN Li; GUO Yi-hong; CHEN Yun-ping; LI Jia-na

    2002-01-01

    The effects to elicit resistance reaction on oilseed rape (Brassica napus L. cv Xinongchangjiao )by four partially N-acetylated chitosan 7B, 8B, 9B and 10B (Degree of acetylation (D. A. ) is 30%, 20%,10%, 0%, respectively) and Glycol chitosan (GC, D.A. is 0%) were investigated and compared. Results showed that chitosan were similar to salicylic acid (SA), and could induce resistance reaction, but the reaction was influenced by the degree of acetylation of chitosan. Fully deacetylated chitosans, 10B and GC, elicited chitinase activity, but partially acetylated chitosan, 7B, 8B and 9B, inhibited chitinase activity. Phenyalanine ammonia-lyase (PAL) was also elicited. Elicitor activity increased with on increasing degree of acetylation, 7B induced highest PAL activity among all chitosans. All chitosans induced peroxidase (POD) in a similar level.After elicited by glycol chitosan, like SA treatment, the seedlings increased disease resistance to Sclerotinia sclerotiorum significantly.

  17. Analysis of urinary N-acetyl-beta-glucosaminidase by capillary zone electrophoresis.

    Science.gov (United States)

    Friedberg, M; Shihabi, Z K

    1997-07-18

    N-Acetyl-beta-glucosaminidase (NAG), a glycosidase enzyme, present in serum, urine and the renal lysosomes is utilized clinically as an early marker for renal damage preceding the elevation of both blood urea nitrogen and creatinine. NAG is analyzed by CE after incubation of urine samples with the synthetic substrate methylumbelliferyl-beta-D-glucosaminide. The reaction mixture is introduced directly into the instrument without further treatment. The released reaction product, 4-methyl-umbelliferone, is separated at 13.2 kV in a 400 mM borate buffer, pH 8.1. Detection was achieved with either ultraviolet absorption or with fluorescence. The fluorescence detection was more sensitive and gave cleaner electropherograms. The CZE method correlated well with an automated kinetic fluorescent assay. 4-Methyl-umbelliferone conjugated to different substrates is used in the analysis of many enzymes involved in the inborn errors of metabolism.

  18. N Acetyl Cysteine, A novel Remedy for Poly Cystic Ovarian Syndrome

    Directory of Open Access Journals (Sweden)

    Nasibeh Amirzargar

    2009-01-01

    Full Text Available Background: Poly cystic ovarian syndrome (PCOS is the most prevalent endocrinopathy among womenand the most common underlying diagnosis for anovulatory infertility. The role of insulin-resistance(IR and hyperinsulinemia in pathophysiology and clinical manifestations of the syndrome depicts theimportance of evaluation of the efficacy of insulin reducing medications. N acetyl cysteine (NAC inhibitsoxidative stress and prevents hyperglycemia induced insulin resistance. This study aims at evaluating theeffects of NAC on manifestations of the disease as well as improvement of fertility status.Materials and Methods: Through a prospective double-blind clinical trial, 46 patients were randomlydivided into one intervention and one control group. The two groups were treated for six weeks aftersimilarity was allocated. All clinical and biochemical indicators were recorded in the early follicularphase both before and after treatment.Results: From each group, 18 patients were ultimately evaluated. In the first group, ovulation rateincreased as compared to the control group. A significant decrease in weight, body mass index (BMI,and waist/hip ratio was also observed. Fast blood sugar (FBS, serum insulin, total cholesterol, lowdensity lipoprotein (LDL levels, and HOMA-IR index also dropped while high density lipoproteinHDL levels elevated significantly. No significant change was reported in luteinizing hormone (LH,FSH, PRL, LH/FSH levels and glucose/insulin ratio. The control group remained unchanged.Conclusion: N- Acetyl Cysteine improves lipid profile, hormonal levels, ovulation status, and longtermhealth of women with PCOS. Considering its limited adverse effects, it can be regarded as asubstitute for insulin reducing medications in treatment of these patients.

  19. Pharmacokinetics and N-acetylation metabolism of S-methyl-l-cysteine and trans-S-1-propenyl-l-cysteine in rats and dogs.

    Science.gov (United States)

    Amano, Hirotaka; Kazamori, Daichi; Itoh, Kenji

    2016-11-01

    1. Pharmacokinetics and N-acetylation metabolism of S-methyl-L-cysteine (SMC) and trans-S-1-propenyl-L-cysteine (S1PC) were examined in rats and dogs. SMC and S1PC (2-5 mg/kg) were well absorbed in both species with high bioavailability (88-100%). 2. SMC and S1PC were excreted only to a small extent in the urine of rats and dogs. The small renal clearance values (5 h) in dogs. 3. S1PC, but not SMC, underwent N-acetylation extensively in vivo, which can be explained by the relative activities of N-acetylation of S1PC/SMC and deacetylation of their N-acetylated forms, N-acetyl-S1PC/N-acetyl-SMC, in the liver and kidney in vitro. The activities for S1PC N-acetylation were similar to or higher than those for N-acetyl-S1PC deacetylation in liver S9 fractions of rat and dog, whereas liver and kidney S9 fractions of rat and dog had little activity for SMC N-acetylation or considerably higher activities for N-acetyl-SMC deacetylation. 4. Our study demonstrated that the pharmacokinetics of SMC and S1PC in rats and dogs was characterized by high bioavailability and extensive renal reabsorption; however, the extent of undergoing the N-acetylation metabolism was extremely different between SMC and S1PC.

  20. Transferases in Polymer Chemistry

    Science.gov (United States)

    van der Vlist, Jeroen; Loos, Katja

    Transferases are enzymes that catalyze reactions in which a group is transferred from one compound to another. This makes these enzymes ideal catalysts for polymerization reactions. In nature, transferases are responsible for the synthesis of many important natural macromolecules. In synthetic polymer chemistry, various transferases are used to synthesize polymers in vitro. This chapter reviews some of these approaches, such as the enzymatic polymerization of polyesters, polysaccharides, and polyisoprene.

  1. Structure and Reactivity of the N-Acetyl-Cysteine Radical Cation and Anion: Does Radical Migration Occur?

    NARCIS (Netherlands)

    Osburn, S.; G. Berden,; Oomens, J.; O' Hair, R. A. J.; Ryzhov, V.

    2011-01-01

    The structure and reactivity of the N-acetyl-cysteine radical cation and anion were studied using ion-molecule reactions, infrared multi-photon dissociation (IRMPD) spectroscopy, and density functional theory (DFT) calculations. The radical cation was generated by first nitrosylating the thiol of N-

  2. Structure and reactivity of the N-acetyl-cysteine radical cation and anion: does radical migration occur?

    NARCIS (Netherlands)

    Osburn, S.; Berden, G.; Oomens, J.; O'Hair, R.A.J.; Ryzhov, V.

    2011-01-01

    The structure and reactivity of the N-acetyl-cysteine radical cation and anion were studied using ion-molecule reactions, infrared multi-photon dissociation (IRMPD) spectroscopy, and density functional theory (DFT) calculations. The radical cation was generated by first nitrosylating the thiol of N-

  3. N-acetyl-S-(1-cyano-2-hydroxyethyl)-L-cysteine, a new urinary metabolite of acrylonitrile and oxiranecarbonitrile.

    Science.gov (United States)

    Linhart, I; Smejkal, J; Novák, J

    1988-01-01

    Two mercapturic acids, i.e., N-acetyl-S-(1-cyano-2-hydroxyethyl)-L-cysteine (CHEMA) and N-acetyl-S-(2-hydroxyethyl)-L-cysteine (HEMA), were isolated from the urine of rats dosed with four successive doses of oxiranecarbonitrile (glycidonitrile, GN), 5 mg/kg, a reactive metabolic intermediate of acrylonitrile (AN). GC-MS analysis of methylated urine extracts from both AN- and GN-dosed rats showed another mercapturate which was identified as N-acetyl-S-(1-cyanoethenyl)-L-cysteine (1-CEMA) methyl ester using an authentic reference sample. The mass spectrum of this compound was very similar to that of a methylated metabolite of AN tentatively identified by Langvardt et al. (1980) as N-acetyl-3-carboxy-5-cyanothiazane (ACCT). In contrast, no ACCT was found in rats dosed with either GN or AN. Hence, there is no evidence for the formation of ACCT or its isomers in rats dosed with AN or GN. The methyl ester of 1-CEMA is formed artificially by dehydration of CHEMA methyl ester in the injector of the gas chromatograph.

  4. Computational Study of Environmental Effects on Torsional Free Energy Surface of N-Acetyl-N'-methyl-L-alanylamide Dipeptide

    Science.gov (United States)

    Carlotto, Silvia; Zerbetto, Mirco

    2014-01-01

    We propose an articulated computational experiment in which both quantum mechanics (QM) and molecular mechanics (MM) methods are employed to investigate environment effects on the free energy surface for the backbone dihedral angles rotation of the small dipeptide N-Acetyl-N'-methyl-L-alanylamide. This computation exercise is appropriate for an…

  5. Cortical N-acetyl aspartate is a predictor of long-term clinical disability in multiple sclerosis

    DEFF Research Database (Denmark)

    Wu, Xingchen; Hanson, Lars G.; Skimminge, Arnold Jesper Møller

    2014-01-01

    Objective: To evaluate the prognostic value of the cortical N-acetyl aspartate to creatine ratio (NAA/Cr) in early relapsing-remitting multiple sclerosis (RRMS). Methods: Sixteen patients with newly diagnosed RRMS were studied by serial MRI and MR spectroscopic imaging (MRSI) once every 6 months ...

  6. Structure and Reactivity of the N-Acetyl-Cysteine Radical Cation and Anion: Does Radical Migration Occur?

    NARCIS (Netherlands)

    Osburn, S.; G. Berden,; Oomens, J.; O' Hair, R. A. J.; Ryzhov, V.

    2011-01-01

    The structure and reactivity of the N-acetyl-cysteine radical cation and anion were studied using ion-molecule reactions, infrared multi-photon dissociation (IRMPD) spectroscopy, and density functional theory (DFT) calculations. The radical cation was generated by first nitrosylating the thiol of N-

  7. Structure and reactivity of the N-acetyl-cysteine radical cation and anion: does radical migration occur?

    NARCIS (Netherlands)

    Osburn, S.; Berden, G.; Oomens, J.; O'Hair, R.A.J.; Ryzhov, V.

    2011-01-01

    The structure and reactivity of the N-acetyl-cysteine radical cation and anion were studied using ion-molecule reactions, infrared multi-photon dissociation (IRMPD) spectroscopy, and density functional theory (DFT) calculations. The radical cation was generated by first nitrosylating the thiol of N-

  8. Structure and Reactivity of the N-Acetyl-Cysteine Radical Cation and Anion: Does Radical Migration Occur?

    NARCIS (Netherlands)

    Osburn, S.; G. Berden,; Oomens, J.; O' Hair, R. A. J.; Ryzhov, V.

    2011-01-01

    The structure and reactivity of the N-acetyl-cysteine radical cation and anion were studied using ion-molecule reactions, infrared multi-photon dissociation (IRMPD) spectroscopy, and density functional theory (DFT) calculations. The radical cation was generated by first nitrosylating the thiol of

  9. Structure and reactivity of the N-acetyl-cysteine radical cation and anion: does radical migration occur?

    NARCIS (Netherlands)

    Osburn, S.; Berden, G.; Oomens, J.; O'Hair, R.A.J.; Ryzhov, V.

    2011-01-01

    The structure and reactivity of the N-acetyl-cysteine radical cation and anion were studied using ion-molecule reactions, infrared multi-photon dissociation (IRMPD) spectroscopy, and density functional theory (DFT) calculations. The radical cation was generated by first nitrosylating the thiol of

  10. Topical effects of N-acetyl-L-hydroxyproline on ceramide synthesis and alleviation of pruritus

    Directory of Open Access Journals (Sweden)

    Hashizume E

    2013-02-01

    Full Text Available Erika Hashizume,1 Tetsuo Nakano,2 Ayako Kamimura,1 Koji Morishita31Healthcare Products Development Center, Kyowa Hakko Bio, Tsukuba, Ibaraki, 2Technical Research Laboratories, Kyowa Hakko Bio, Hofu, Yamaguchi, 3Technology Development and Research Department, Kyowa Hakko Bio, Tokyo, JapanPurpose: N-acetyl-l-hydroxyproline (AHYP is an acetylated form of l-hydroxyproline that is used to treat skin ulcers and porphyria cutanea tarda. Its other biological and physiological effects on the skin have not been elucidated. We investigated the effects of AHYP on the skin-barrier function, focusing on ceramide synthesis and the effects of topical AHYP on atopic dermatitis.Materials and methods: AHYP was applied to a three-dimensional cultured skin model. Ceramides were quantified by high-performance thin-layer chromatography. Serine palmitoyltransferase (SPT is the rate-limiting enzyme in de novo ceramide synthesis, and the mRNA of its long-chain base subunit 1 (SPTLC1 was evaluated by quantitative reverse-transcription polymerase chain reaction. A clinical trial in the form of an intraindividual, comparative, double-blind, randomized, vehicle-controlled test involving 15 female subjects suffering from slight atopic dermatitis was performed. Subjects applied 1% (w/w AHYP cream to one forearm and a control cream to the other forearm twice daily for 4 weeks. Skin condition was evaluated by measuring transepidermal water loss (TEWL. Dermatological observations were made by a dermatologist, and subjects evaluated their own pruritus intensity before beginning treatment and 4 weeks after the start of treatment.Results: SPTLC1 expression and ceramide synthesis were significantly increased in an AHYP-treated skin model (P < 0.05. In the clinical trial, no adverse effects were observed in any subjects. TEWL was increased in the control-treated region of the forearm (P < 0.05 after 4 weeks' application, whereas there was no change in the AHYP-treated region of the

  11. Transferases in Polymer Chemistry

    NARCIS (Netherlands)

    van der Vlist, Jeroen; Loos, Katja; Palmans, ARA; Heise, A

    2010-01-01

    Transferases are enzymes that catalyze reactions in which a group is transferred from one compound to another. This makes these enzymes ideal catalysts for polymerization reactions. In nature, transferases are responsible for the synthesis of many important natural macromolecules. In synthetic polym

  12. N-acetyl-l-histidine, a Prominent Biomolecule in Brain and Eye of Poikilothermic Vertebrates

    Directory of Open Access Journals (Sweden)

    Morris H. Baslow

    2015-04-01

    Full Text Available N-acetyl-l-histidine (NAH is a prominent biomolecule in brain, retina and lens of poikilothermic vertebrates. In fish lens, NAH exhibits an unusual compartmentalized metabolism. It is synthesized from L-histidine (His and acetyl Co-enzyme A. However, NAH cannot be catabolized by lens cells. For its hydrolysis, NAH is exported to ocular fluid where a specific acylase cleaves His which is then actively taken up by lens and re-synthesized into NAH. This energy-dependent cycling suggested a pump mechanism operating at the lens/ocular fluid interface. Additional studies led to the hypothesis that NAH functioned as a molecular water pump (MWP to maintain a highly dehydrated lens and avoid cataract formation. In this process, each NAH molecule released to ocular fluid down its gradient carries with it 33 molecules of bound water, effectively transporting the water against a water gradient. In ocular fluid the bound water is released for removal from the eye by the action of NAH acylase. In this paper, we demonstrate for the first time the identification of NAH in fish brain using proton magnetic resonance spectroscopy (MRS and describe recent evidence supporting the NAH MWP hypothesis. Using MRS, we also document a phylogenetic transition in brain metabolism between poikilothermic and homeothermic vertebrates.

  13. N-acetyl-L-histidine, a Prominent Biomolecule in Brain and Eye of Poikilothermic Vertebrates.

    Science.gov (United States)

    Baslow, Morris H; Guilfoyle, David N

    2015-04-24

    N-acetyl-L-histidine (NAH) is a prominent biomolecule in brain, retina and lens of poikilothermic vertebrates. In fish lens, NAH exhibits an unusual compartmentalized metabolism. It is synthesized from L-histidine (His) and acetyl Co-enzyme A. However, NAH cannot be catabolized by lens cells. For its hydrolysis, NAH is exported to ocular fluid where a specific acylase cleaves His which is then actively taken up by lens and re-synthesized into NAH. This energy-dependent cycling suggested a pump mechanism operating at the lens/ocular fluid interface. Additional studies led to the hypothesis that NAH functioned as a molecular water pump (MWP) to maintain a highly dehydrated lens and avoid cataract formation. In this process, each NAH molecule released to ocular fluid down its gradient carries with it 33 molecules of bound water, effectively transporting the water against a water gradient. In ocular fluid the bound water is released for removal from the eye by the action of NAH acylase. In this paper, we demonstrate for the first time the identification of NAH in fish brain using proton magnetic resonance spectroscopy (MRS) and describe recent evidence supporting the NAH MWP hypothesis. Using MRS, we also document a phylogenetic transition in brain metabolism between poikilothermic and homeothermic vertebrates.

  14. Synthesis, characterization, antibacterial activity and quantum chemical studies of N'-Acetyl propane sulfonic acid hydrazide

    Science.gov (United States)

    Alyar, Saliha; Alyar, Hamit; Ozdemir, Ummuhan Ozmen; Sahin, Omer; Kaya, Kerem; Ozbek, Neslihan; Gunduzalp, Ayla Balaban

    2015-08-01

    A new N'-Acetyl propane sulfonic acid hydrazide, C3H7sbnd SO2sbnd NHsbnd NHsbnd COCH3 (Apsh, an sulfon amide compound) has been synthesized for the first time. The structure of Apsh was investigated using elemental analysis, spectral (IR, 1H/13C NMR) measurements. In addition, molecular structure of the Apsh was determined by single crystal X-ray diffraction technique and found that the compound crystallizes in monoclinic, space group P 21/c. 1H and 13C shielding tensors for crystal structure were calculated with GIAO/DFT/B3LYP/6-311++G(d,p) methods in CDCl3. The structure of Apsh is optimized using Density Functional Theory (DFT) method. The vibrational band assignments were performed at B3LYP/6-311++G(d,p) theory level combined with scaled quantum mechanics force field (SQMFF) methodology. The theoretical IR frequencies are found to be in good agreement with the experimental IR frequencies. Nonlinear optical (NLO) behaviour of Apsh is also examined by the theoretically predicted values of dipole moment (μ), polarizability (α0) and first hyperpolarizability (βtot). The antibacterial activities of synthesized compound were studied against Gram positive bacteria: Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 23212, Staphylococcus epidermidis ATCC 34384, Gram negative bacteria: Eschericha coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 70063 by using microdilution method (as MICs) and disc diffusion method.

  15. The Role of Poly N Acetyl Glucosamine Nanofibers in Cutaneous Wound Healing

    Science.gov (United States)

    Buff-Lindner, Amanda Haley

    Treatment of cutaneous wounds with poly-N-acetyl-glucosamine nanofibers (pGlcNAc), a novel polysaccharide material derived from a marine diatom, results in increases in wound closure, antibacterial activities and innate immune responses. Treatment with nanofibers results in increased defensin, small antimicrobial peptides, expression both in vitro and in vivo. Induction of defensin expression results in bacterial clearance in a cutaneous wound model. Our data show that Akt1 plays a central role in the regulation of these activities. Interestingly, pGlcNAc treatment of cutaneous wounds in mice results in decreased scar sizes. Additionally, treatment of cutaneous wounds with pGlcNAc results in increased elasticity and a rescue of tensile strength. Masson Trichrome staining suggests that pGlcNAc treated wounds exhibit decreased collagen content as well as increased collagen alignment with collagen fibers oriented similarly to unwounded tissue. Utilizing a fibrin gel assay to analyze the effect of pGlcNAc nanofiber treatment on fibroblast alignment in vitro, pGlcNAc stimulation of embedded fibroblasts results in fibroblasts alignment as compared to untreated controls, by a process that is Akt1 dependent. Our data show that in Akt1 null animals pGlcNAc treatment does not increase tensile strength or elasticity. Taken together, our findings suggest that pGlcNAc nanofibers stimulate an Akt1 dependent pathway that results in wound closure, the proper alignment of fibroblasts, decreased scarring, and increased tensile strength during cutaneous wound healing.

  16. [N-acetyl-beta-hexosaminidase--marker of damage to renal proximal tubules].

    Science.gov (United States)

    Kepka, Alina; Szajda, Sławomir D; Jankowska, Anna; Waszkiewicz, Napoleon; Chojnowska, Sylwia; Zwierz, Krzysztof

    2008-09-01

    Cells of the renal epithelium synthesize and excrete to urine many enzymes. Among more than 50 enzymes produced by epithelial cells of proximal tubules, only few have a diagnostic value. Determination of the enzymatic activities in urine is sensitive and not invasive method for evaluation the function of renal tubules. Urinary N-acetyl-beta-hexosaminidase (HEX) activity is approved and practically utilized marker of the renal function. HEX is a lysosomal exoglycosidase taking part in catabolism of the sugar chains of glycoconjugates (glycoproteins, glycolipids and proteoglycans). HEX catalyses release of N-acetylglucosamine and N-acetylgalactosamine from a non reducing ends of glycoconjugates. In urine of healthy persons activity of HEX is negligible, but significantly increases after damage to the proximal tubules. The cells of renal proximal tubules are very sensitive to hypoxia. Therefore all renal processes with hypoxia lead to dysfunction of proximal renal tubules and release HEX to urine. Increased activity of HEX in urine was found after intoxication by heavy metals, nephrotoxic drugs, contrast media, fewer, bacterial as well as immunological nephritis and hypertension, diabetes, neoplasms and during renal graft rejection. In the paper we presented review of literature concerning HEX, and its presence in renal tissue and urine, as well as application in diagnostics.

  17. The effect of N-acetyl-L-cysteine on the viscosity of ileal neobladder mucus.

    Science.gov (United States)

    Schrier, B P; Lichtendonk, W J; Witjes, J A

    2002-05-01

    N-acetyl-L-cysteine (NAC) proved to be an effective mucolytic in pulmonary secretions. Our goal was to investigate the in vitro effect of NAC on viscosity of ileal neobladder mucus. The urine of a patient with an ileal neobladder was collected during the first 7 days postoperatively and stored in a refrigerator. After precipitation, the urine was decanted. The residue was stirred to a homogeneous suspension. To samples of 4.5 ml mucus, 0.5 ml NAC 10% was added. To the control sample, 0.5 ml water was added. The samples were incubated in a water bath at 37 degrees C for 5, 30 and 60 min. Viscosity was measured in the Bohlin VOR Rheometer. The viscosity of the ileal neobladder mucus decreased quickly after incubating with NAC 10%. Viscosity increased slightly after I h of incubation. The viscosity in the control sample was higher than in the other incubated samples. NAC was found to decrease the viscosity of ileal neobladder mucus, supporting the in vivo experience that NAC can be useful in patients with an ileal neobladder to facilitate the evacuation of mucus by decreasing viscosity.

  18. Dexamethasone and N-acetyl-cysteine attenuate Pseudomonas aeruginosa-induced mucus expression in human airways.

    Science.gov (United States)

    Sprenger, Lisa; Goldmann, Torsten; Vollmer, Ekkehard; Steffen, Armin; Wollenberg, Barbara; Zabel, Peter; Hauber, Hans-Peter

    2011-04-01

    Infection with Pseudomonas aeruginosa (PA) induces mucus hypersecretion in airways. Therapeutic options to attenuate excessive mucus expression are sparse. To investigate the effect of steroids and N-acetyl-cysteine (NAC) on PA-induced mucus expression. Calu-3 cells and explanted human mucosa from the upper airways were stimulated with either PA, lipopolysaccharide from alginate producing PA (smooth, sPA-LPS) or non-alginate producing PA (rough, rPA-LPS). Dexamethasone (DEX) and NAC were added in different concentrations. Expression of mucin (MUC5AC) gene and mucin protein expression was quantified using PAS (periodic acids Schiff) staining and real time PCR. PA, sPA-LPS or rPA-LPS significantly induced mucin protein and MUC5AC gene expression in Calu-3 cells and explanted mucosal tissue (P NAC significantly decreased PA-, sPA-LPS- and rPA-LPS-induced mucin protein expression both in vitro and ex vivo (P 0.05). Our data show that both an anti-inflammatory drug (DEX) and an anti-oxidative agent (NAC) can attenuate PA-induced mucus expression in human airways. These results support the use of steroids and NAC in clinical practice to treat PA-induced mucus hypersecretion. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Electrochemical behaviour of N-acetyl-L-cysteine on gold electrode - A tentative reaction mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Barus, C.; Gros, P.; Comtat, M. [Laboratoire de Genie Chimique, UMR 5503, Universite Paul Sabatier, Departement Procedes Electrochimiques, 31062 Toulouse Cedex 9 (France); Daunes-Marion, S.; Tarroux, R. [Societe Pierre Fabre Dermo-Cosmetique, Service Pharmocochimie, Allee Camille Soula, Vigoulet Auzil, BP 74, 31322 Castanet Tolosan (France)

    2007-11-01

    The electrochemical behaviour of N-acetyl-L-cysteine (NAC) has been investigated by linear and cyclic voltammetry on gold electrode at room temperature. The results showed two oxidation peaks under acid and neutral conditions and only one in basic medium. For each oxidation, as many electron was exchanged as proton. The influence of both the concentration and the potential scan rate on the peak currents highlighted a diffusion-controlled phenomenon for the first peak and an adsorption-limited reaction rate for the second one. The diffusion coefficient of NAC in solution and the surface concentration of the adsorbed species at pH 3 and 7 were close to 2 x 10{sup -4} to 2 x 10{sup -5} cm{sup 2} s{sup -1} and 6 x 10{sup -9} to 6 x 10{sup -10} mol cm{sup -2}, respectively. Film transfer experiments resulted in an irreversible adsorption of NAC on gold electrode, and the formation of a self-assembled monolayer (SAM). (author)

  20. Electrochemical behaviour of N-acetyl-L-cysteine on gold electrode-A tentative reaction mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Barus, C. [Laboratoire de Genie Chimique, UMR 5503, Universite Paul Sabatier, Departement Procedes Electrochimiques, 31062 Toulouse Cedex 9 (France)], E-mail: barus@chimie.ups-tlse.fr; Gros, P.; Comtat, M. [Laboratoire de Genie Chimique, UMR 5503, Universite Paul Sabatier, Departement Procedes Electrochimiques, 31062 Toulouse Cedex 9 (France); Daunes-Marion, S.; Tarroux, R. [Societe Pierre Fabre Dermo-Cosmetique, Service Pharmocochimie, Allee Camille Soula, Vigoulet Auzil, BP 74, 31322 Castanet Tolosan (France)

    2007-11-01

    The electrochemical behaviour of N-acetyl-L-cysteine (NAC) has been investigated by linear and cyclic voltammetry on gold electrode at room temperature. The results showed two oxidation peaks under acid and neutral conditions and only one in basic medium. For each oxidation, as many electron was exchanged as proton. The influence of both the concentration and the potential scan rate on the peak currents highlighted a diffusion-controlled phenomenon for the first peak and an adsorption-limited reaction rate for the second one. The diffusion coefficient of NAC in solution and the surface concentration of the adsorbed species at pH 3 and 7 were close to 2 x 10{sup -4} to 2 x 10{sup -5} cm{sup 2} s{sup -1} and 6 x 10{sup -9} to 6 x 10{sup -10} mol cm{sup -2}, respectively. Film transfer experiments resulted in an irreversible adsorption of NAC on gold electrode, and the formation of a self-assembled monolayer (SAM)

  1. Association between Urinary N-Acetyl-Beta-D-Glucosaminidase and Microalbuminuria in Diabetic Black Africans

    Directory of Open Access Journals (Sweden)

    Francis Patrick Udomah

    2012-01-01

    Full Text Available Diabetes mellitus is the commonest cause of ESRD worldwide and third most common cause in Nigeria. Recent reports from Nigeria indicate the prevalence of diabetic nephropathy as an aetiology of ESRD is increasing necessitating early diagnosis of diabetic nephropathy. We measured the urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG, NAG/creatinine ratio, urinary protein-creatinine ratio and calculated eGFR in 30 recently diagnosed nonhypertensive diabetics and 67 controls. The age and sex distribution, systolic blood pressure, serum and urinary creatinine were similar for both groups. There was higher urinary excretion of NAG (304 versus 184 μmol/h/L, <0.001 and NAG/creatinine ratio (21.2 versus 15.7 μmol/h/L/mmolCr, <0.001 in the diabetics than controls. There was a strong correlation between NAG/creatinine ratio and albumin/creatinine ratio (=0.74, <0.001. A multivariate linear regression model showed a significant linear relationship between NAG/creatinine ratio and albumin/creatinine ratio after adjusting for the effect of blood pressure, age, sex, and serum creatinine. The strong association found between albumin/creatinine ratio and NAG/creatinine ratio perhaps indicates the need for further investigation of the clinical utility of NAG/creatinine ratio as a screening tool for early nephropathy in African diabetics.

  2. N-Acetyl Cysteine (NAC)-Directed Detoxification of Methacryloxylethyl Cetyl Ammonium Chloride (DMAE-CB).

    Science.gov (United States)

    Jiao, Yang; Ma, Sai; Li, Jing; Shan, Lequn; Wang, Yingjie; Tian, Min; Yang, Yanwei; Sun, Jinlong; Ban, Jinghao; Chen, Jihua

    2015-01-01

    Methacryloxylethyl cetyl ammonium chloride (DMAE-CB) is a polymerizable antibacterial monomer and has been proved as an effective strategy to achieve bioactive bonding with reliable bacterial inhibitory effects. However, the toxicity of DMAE-CB may hamper its wide application in clinical situations. Thus, this study was designed to investigate the toxicity of DMAE-CB and explore the possible protective effects of N-acetyl cysteine (NAC). High performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) analysis showed that chemical binding of NAC and DMAE-CB occurred in a time dependent manner. Pre-incubation of fourty-eight hours is required for adequate reaction between DMAE-CB and NAC. DMAE-CB reduced human dental pulp cells (hDPCs) viability in a dose-dependent manner. The toxic effects of DMAE-CB were accompanied by increased reactive oxygen species (ROS) level and reduced glutathione (GSH) content. NAC alleviated DMAE-CB-induced oxidative stress. Annexin V/ Propidium Iodide (PI) staining and Hoechst 33342 staining indicated that DMAE-CB induced apoptosis. Collapsed mitochondrial membrane potential (MMP) and activation of caspase-3 were also observed after DMAE-CB treatment. NAC rescued hDPCs from DMAE-CB-induced apoptosis, accompanied by lower level of MMP loss and caspase-3 activity. This study assists to elucidate the mechanism underlying the cytotoxic effects of DMAE-CB and provides theoretical supports for the searching of effective strategies to reduce toxicity of quaternary ammonium dental monomers.

  3. N-Acetyl Cysteine Inhibits Endothelin-1-Induced ROS Dependent Cardiac Hypertrophy through Superoxide Dismutase Regulation

    Directory of Open Access Journals (Sweden)

    Sobia Mushtaq

    2015-07-01

    Full Text Available Objective: Oxidative stress down regulates antioxidant enzymes including superoxide dismutase (SOD and contributes to the development of cardiac hypertrophy. N-Acetyl cysteine (NAC can enhance the SOD activity, so the aim of this study is to highlight the inhibitory role of NAC against endothelin-1 (ET-1-induced cardiac hypertrophy. Materials and Methods: In this experimental study at QAU from January, 2013 to March, 2013. ET-1 (50 μg/kg and NAC (50 mg/kg were given intraperitoneally to 6-day old neonatal rats in combination or alone. All rats were sacrificed 15 days after the final injection. Histological analysis was carried out to observe the effects caused by both drugs. Reactive oxygen species (ROS analysis and SOD assay were also carried out. Expression level of hypertrophic marker, brain natriuretic peptide (BNP, was detected by western blotting. Results: Our findings showed that ET-1-induced cardiac hypertrophy leading towards heart failure was due to the imbalance of different parameters including free radical-induced oxidative stress and antioxidative enzymes such as SOD. Furthermore NAC acted as an antioxidant and played inhibitory role against ROS-dependent hypertrophy via regulatory role of SOD as a result of oxidative response associated with hypertrophy. Conclusion: ET-1-induced hypertrophic response is associated with increased ROS production and decreased SOD level, while NAC plays a role against free radicals-induced oxidative stress via SOD regulation.

  4. Effect of N-acetyl-l-cysteine on Saccharomyces cerevisiae irradiated with gamma-rays.

    Science.gov (United States)

    Kim, Jin Kyu; Park, Jiyoung; Ryu, Tae Ho; Nili, Mohammad

    2013-07-01

    Ionizing radiation (IR) induces DNA strand breaks (DSBs), base damage, inhibition of protein activity, apoptosis by reactive oxygen species (ROS). Detoxification or removal of generated ROS can reduce oxidative damage. Antioxidant enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase are immediately triggered for ROS scavenging. N-acetyl-l-cysteine (NAC) having a thiol, a precursor for reduced glutathione (GSH), is known as one of the antioxidants. In this study, the effect of NAC as an antioxidant and a radioprotector was investigated on survival rate, transcriptional level of antioxidant enzymes gene, and protein level including SOD activity and intracellular GSH in yeast Saccharomyces cerevisiae W303-1A strain mutated YBP1 gene irradiated with gamma-rays. NAC did not protect the gamma-ray-induced cell death. The gene expression of antioxidant enzymes including SOD1, SOD2, GPX1, and GPX2 was induced by gamma-rays. In contrast, the pretreatment of NAC reduced the expression of these genes. NAC reduced SOD activity and intracellular GSH level in yeast. These data suggest that NAC is able to reduce radiation-induced ROS levels in vivo but does not protect yeast cells against radiation-induced death.

  5. N-acetyl cysteine in clomiphene citrate resistant polycystic ovary syndrome: A review of reported outcomes.

    Science.gov (United States)

    Saha, Lekha; Kaur, Sharonjeet; Saha, Pradip Kumar

    2013-07-01

    Clomiphene citrate (CC) has been the gold-standard drug for ovulation induction in polycystic ovary syndrome (PCOS), but still CC resistance is seen in approximately 15-40% in women with PCOS. N-acetyl cysteine (NAC), a safe and cheap drug available in the market many years ago as mucolytic agent, was found to have a role in infertility management. Recently, some reports discussed the possible beneficial effects of NAC on ovulation. The biological properties of the NAC make this drug a potential candidate for its use in the infertility treatment, especially in the PCOS in inducing or augmenting ovulation. An updated electronic search was performed through PUBMED, MEDLINE, and COCHRANE and focused on peer-reviewed, full text, randomized controlled trials, and observational cohort or case-control studies for role of NAC in CC-resistant PCOS. Thorough search through all the clinical studies showed mixed results. Studies with positive results showed improvement in induction of ovulation as compared to negative studies showing contrary results. More randomized clinical trials are still needed to establish its definitive role in CC-resistant PCOS.

  6. N -acetyl cysteine in clomiphene citrate resistant polycystic ovary syndrome: A review of reported outcomes

    Directory of Open Access Journals (Sweden)

    Lekha Saha

    2013-01-01

    Full Text Available Clomiphene citrate (CC has been the gold-standard drug for ovulation induction in polycystic ovary syndrome (PCOS, but still CC resistance is seen in approximately 15-40% in women with PCOS. N-acetyl cysteine (NAC, a safe and cheap drug available in the market many years ago as mucolytic agent, was found to have a role in infertility management. Recently, some reports discussed the possible beneficial effects of NAC on ovulation. The biological properties of the NAC make this drug a potential candidate for its use in the infertility treatment, especially in the PCOS in inducing or augmenting ovulation. An updated electronic search was performed through PUBMED, MEDLINE, and COCHRANE and focused on peer-reviewed, full text, randomized controlled trials, and observational cohort or case-control studies for role of NAC in CC-resistant PCOS. Thorough search through all the clinical studies showed mixed results. Studies with positive results showed improvement in induction of ovulation as compared to negative studies showing contrary results. More randomized clinical trials are still needed to establish its definitive role in CC-resistant PCOS.

  7. The lysosomal N-acetyl-beta-D-glucosaminidase (NAG) isoenzymes in plasma: study of distribution in a general population by a simple routine chromatofocusing procedure.

    Science.gov (United States)

    Goi, G; Bairati, C; Roggi, C; Maccarini, L; Tettamanti, G; Meloni, C; Lombardo, A

    1993-11-30

    We have adapted for routine analysis a pre-existing method for separating the three major N-acetyl-beta-D-glucosaminidase (NAG) isoenzyme forms--A, B+I1 and I2--by chromatofocusing followed by fluorimetric assay of the enzyme activity. This method combines good resolution, accurate quantification of the different isoenzymes and high reproducibility with an acceptable degree of analytical precision. We have applied it to studying the isoenzyme levels in the plasma of a general population of 417 subjects and have analysed these enzyme activities as functions of age, sex, body mass and declared alcohol consumption. Unlike the levels of unfractionated enzyme, levels of all the isoenzymes were higher in men than in women at all ages except in the 20-29 year group. Isoenzyme I2 showed the greatest sex difference. On the whole, with increasing age, both sexes showed more or less regular increases in plasma levels of all the isoenzymes. We also found significant correlations for the population as a whole with age and with body mass index. The only significant correlation with alcohol consumption was for B+I1 in men.

  8. Effect of N-acetyl cysteine and glycine supplementation on growth performance, glutathione synthesis, anti-oxidative and immune ability of Nile tilapia, Oreochromis niloticus.

    Science.gov (United States)

    Xie, Shiwei; Zhou, Weiwen; Tian, Lixia; Niu, Jin; Liu, Yongjian

    2016-08-01

    An 8-week feeding trial was conducted to evaluate the effect of N-acetyl cysteine (NAC) and glycine supplementation on growth performance, glutathione (GSH) synthesis, anti-oxidative and immune ability of Nile tilapia, Oreochromis niloticus. Four practical diets were formulated, control, control +0.2% NAC, control +0.5% glycine, control +0.2% NAC +0.5% glycine. Each diet was randomly assigned to quadruplicate groups of 30 fish (approximately 9.5 g). The weight gain and specific growth rate were significantly increased with the supplementation of NAC and glycine. While they had no effect on feed efficiency feed intake and survival. Glutathion peroxidase (GPx) was increased by NAC and γ-glutamine cysteine synthase (γ-GCS) in plasma were increased by glycine. After the feeding trail, fish were challenged by Streptococcus iniae, fish fed the diet supplemented with NAC obtained significantly higher survival rate after 72 h challenge test. NAC also decreased malonaldehyde (MDA) in liver, increased glutathione S-transferase (GST) activity in plasma, up-regulated mRNA expression of Superoxide dismutase (SOD) and GPx in liver and headkidney. Dietary supplementation of glycine increased the anti-oxidative ability of tilapia through increase anti-oxidative enzyme activity (SOD, glutathione reductase, myeloperoxidase) and up-regulate anti-oxidative gene expression (SOD). Immune ability only enhanced by the supplementation of NAC through increased interleukin-1β (IL-1β) mRNA expression. These results clearly indicated that the supplementation of NAC and glycine can significantly improve the growth performance of tilapia, and NAC also enhance the anti-oxidative and immune capacity of tilapia, glycine could only enhance the anti-oxidative ability.

  9. Biochemical and molecular mechanisms of N-acetyl cysteine and silymarin-mediated protection against maneb- and paraquat-induced hepatotoxicity in rats.

    Science.gov (United States)

    Ahmad, Israr; Shukla, Smriti; Kumar, Ashutosh; Singh, Brajesh Kumar; Kumar, Vinod; Chauhan, Amit Kumar; Singh, Dhirendra; Pandey, Haushila Prasad; Singh, Chetna

    2013-01-25

    Oxidative stress is one of the major players in the pathogenesis of maneb (MB) and paraquat (PQ)-induced disorders. N-acetyl cysteine (NAC), a glutathione (GSH) precursor and silymarin (SIL), a naturally occurring antioxidant, encounter oxidative stress-mediated cellular damage. The present study was aimed to investigate the effects of NAC and SIL against MB and/or PQ-induced hepatotoxicity in rats. The levels of hepatotoxicity markers - alanine aminotransaminase (ALT), aspartate aminotransaminase (AST) and total bilirubin, histological changes, oxidative stress indices, phase I and phase II xenobiotic metabolizing enzymes - cytochrome P450 (CYP) and glutathione S-transferase (GST) and pro-inflammatory molecules - inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were measured in animals treated with MB and/or PQ in the presence or absence of NAC and SIL. MB and/or PQ augmented ALT, AST, total bilirubin, lipid peroxidation and nitrite contents and catalytic activities of superoxide dismutase and glutathione peroxidase however, the GSH content was attenuated. NAC and SIL restored the above-mentioned alterations towards basal levels but the restorations were more pronounced in SIL treated groups. Similarly, MB and/or PQ-mediated histopathological symptoms and changes in the catalytic activities/expressions of CYP1A2, CYP2E1, iNOS, TNF-α, and IL-1β were alleviated by NAC and SIL. Conversely, MB and/or PQ-induced GSTA4-4 expression/activity was further increased by NAC/SIL and glutathione reductase activity was also increased. The results obtained thus suggest that NAC and SIL protect MB and/or PQ-induced hepatotoxicity by reducing oxidative stress, inflammation and by modulating xenobitic metabolizing machinery and SIL seems to be more effective.

  10. Statistical evaluation of the isoform patterns of N-acetyl-beta-hexosaminidase from human renal cancer tissue separated by isoelectrofocusing.

    Science.gov (United States)

    Borzym-Kluczyk, Malgorzata; Radziejewska, Iwona; Olszewska, Ewa; Szajda, Sławomir; Knaś, Małgorzata; Zwierz, Krzysztof

    2007-03-01

    Isoenzymes of HEX from human renal carcinoma and neighbouring macroscopically normal renal tissue can show different patterns on isoelectrofocusing gels. The aim of our work was to elaborate the method for statistical evaluation of differences. Isoenzymes of N-acetyl-beta-hexosaminidase were separated from renal (control and cancerous) tissues of 15 patients. Isoenzymes were electrofocused in Multiphor II, with ampholine pH 3.5-9.0 (2%) and then evaluated densitometrically and analysed statistically. A similar pattern in activity of isoforms of isoenzymes A and B in normal and cancerous renal tissue was observed. The proposed method of statistical evaluation of differences in isoforms of N-acetyl-beta-glucosaminidase can also be adapted to estimate the isoforms of other enzymes in different tissues.

  11. Quantification of N-Acetyl Aspartyl Glutamate in Human Brain using Proton Magnetic Resonance Spectroscopy at 7 T

    Science.gov (United States)

    Elywa, M.

    2015-07-01

    The separation of N-acetyl aspartyl glutamate (NAAG) from N-acetyl aspartate (NAA) and other metabolites, such as glutamate, by in vivo proton magnetic resonance spectroscopy at 7 T is described. This method is based on the stimulated echo acquisition mode (STEAM), with short and long echo time (TE) and allows quantitative measurements of NAAG in the parietal and pregenual anterior cingulate cortex (pgACC) of human brain. Two basesets for the LCModel have been established using nuclear magnetic resonance simulator software (NMR-SIM). Six healthy volunteers (age 25-35 years) have been examined at 7 T. It has been established that NAAG can be separated and quantified in the parietal location and does not get quantified in the pgACC location when using a short echo time, TE = 20 ms. On the other hand, by using a long echo time, TE = 74 ms, NAAG can be quantified in pgACC structures.

  12. Effect of smoking on activity of N-acetyl-beta-hexosaminidase in serum and urine of renal cancer patients.

    Science.gov (United States)

    Borzym-Kluczyk, Malgorzata; Radziejewska, Iwona; Zaniewska, Agnieszka; Borzym-Lewszuk, Anna; Szajda, Sławomir Dariusz; Knaś, Malgorzata; Zwierz, Krzysztof; Darewicz, Barbara

    2009-10-01

    To compare N-acetyl-beta-hexosaminidase (HEX) activity in the serum and urine of smokers as well as non-smokers with renal cancer, and healthy people. To assess hexosaminidase activity the level of p-nitrophenol released from p-nitrophenol derivatives was measured. The activity of enzyme was significantly higher in cancer group, with the highest activity in non-smokers. Cigarette smoking can inhibit, by the influence on HEX activity, catabolism of oligosaccharide chains in cancer tissues.

  13. Widespread N-acetyl-D-glucosamine uptake among pelagic marine bacteria and its ecological implications.

    Science.gov (United States)

    Riemann, Lasse; Azam, Farooq

    2002-11-01

    Dissolved free and combined N-acetyl-D-glucosamine (NAG) is among the largest pools of amino sugars in the ocean. NAG is a main structural component in chitin and a substantial constituent of bacterial peptidoglycan and lipopolysaccharides. We studied the distribution and kinetics of NAG uptake by the phosphoenolpyruvate:NAG phosphotransferase systems (PTS) in marine bacterial isolates and natural bacterial assemblages in near-shore waters. Of 78 bacterial isolates examined, 60 took up 3H-NAG, while 18 showed no uptake. No systematic pattern in NAG uptake capability relative to phylogenetic affiliation was found, except that all isolates within Vibrionaceae took up NAG. Among 12 isolates, some showed large differences in the relationship between polymer hydrolysis (measured as chitobiase activity) and uptake of the NAG, the hydrolysis product. Pool turnover time and estimated maximum ambient concentration of dissolved NAG in samples off Scripps Pier (La Jolla, Calif.) were 5.9 +/- 3.0 days (n = 10) and 5.2 +/- 0.9 nM (n = 3), respectively. Carbohydrate competition experiments indicated that glucose, glucosamine, mannose, and fructose were taken up by the same system as NAG. Sensitivity to the antibiotic and NAG structural analog streptozotocin (STZ) was developed into a culture-independent approach, which demonstrated that approximately one-third of bacteria in natural marine assemblages that were synthesizing DNA took up NAG. Isolates possessing a NAG PTS system were found to be predominantly facultative anaerobes. These results suggest the hypothesis that a substantial fraction of bacteria in natural pelagic assemblages are facultative anaerobes. The adaptive value of fermentative metabolism in the pelagic environment is potentially significant, e.g., to bacteria colonizing microenvironments such as marine snow that may experience periodic O2-limitation.

  14. Can N-acetyl-L-cysteine affect zinc metabolism when used as a paracetamol antidote?

    Science.gov (United States)

    Brumas, V; Hacht, B; Filella, M; Berthon, G

    1992-07-01

    N-Acetyl-L-cysteine (NAC) has long been used in the treatment of chronic lung diseases. Inhalation and oral administration of the drug are both effective in reducing mucus viscosity. In addition, NAC oral therapy allows to restore normal mucoprotein secretion in the long term. Although displaying heavy metal-complexing potential, NAC exerts no detectable influence on the metabolism of essential trace metals when used in the above context (i.e. at doses near 600 mg day-1). However, this may no longer be the case when NAC is used as an oxygen radical scavenger, like in the treatment of paracetamol poisoning. In the latter case, intravenous doses as high as 20 g day-1 are administered, which may induce excessive zinc urinary excretion. In order to allow a better appreciation of the risk of zinc depletion during NAC therapy, the present work addresses the role of this drug towards zinc metabolism at the molecular level. First, formation constants for zinc-NAC complexes have been determined under physiological conditions. Then, computer simulations for blood plasma and gastrointestinal fluid have been run to assess the influence of NAC and its metabolites (e.g. cysteine and glutathione) on zinc excretion and absorption. Blood plasma simulations reveal that NAC can effectively mobilise an important fraction of zinc into urinary excretable complexes as from concentrations of 10(-3) mol dm-3 (which corresponds to a dose of about 800 mg). This effect can still be enhanced by the action of NAC metabolites, among which cysteine is the most powerful zinc sequestering agent. In contrast, simulations relative to gastrointestinal conditions suggest that NAC should tend to increase zinc absorption, regardless of its dose.

  15. Nanostructured Lipid Carrier for Topical Application of N-Acetyl Glucosamine

    Science.gov (United States)

    Aliasgharlou, Lavin; Ghanbarzadeh, Saeed; Azimi, Hamideh; Zarrintan, Mohammad Hossein; Hamishehkar, Hamed

    2016-01-01

    Purpose: Hyperpigmentation occurs when melanin is overproduced in certain spots on the skin and is one of the most challenging skin conditions to treat. Although it is usually harmless, for cosmetic reasons, it is dreadfully bothersome to those who undergo it. It was reported that N-acetyl-glucosamine (NAGA) prevents melanin synthesis and alters the expression of numerous genes related to pigmentation. In spite of these advantages, NAGA cannot be employed in topical formulations due to its extremely polar characteristics. Nanoparticles, especially lipid-based ones, have been introduced as an efficient carrier for dermal drug delivery. Methods: The aim of the present study was to load adequate hydrophilic NAGA to the lipophilic nanostructured lipid carriers (NLCs) for potential dermal application. Methods: NAGA-loaded NLCs were formulated, using hot homogenization technique, and the characteristics of the optimized formulation were analyzed by laser light scattering, X-ray diffraction, and scanning electron microscopy methods. Loading capacity percentage and in vitro release study were carried out by applying a validated HPLC method. The optimum formulation was utilized for the in vivo skin lightening evaluations in healthy volunteers. Results: NAGA-loaded NLCs demonstrated promising results (the size of 190 nm, narrow size distribution, loading capacity of 9%, and appropriate NAGA release profile) suitable for dermal delivery. XRD results exhibited a dramatic reduction in the crystalline structure of encapsulated NAGA. Dermoscopy images indicated a considerable decline in melanin distribution pattern in the majority of the cases treated with NAGA-loaded NLCs. Conclusion: Thus, this study has opened new horizons for the potential use of lipid based nanoparticles in the managing of hyperpigmentation. PMID:28101465

  16. Determination of N-acetyl-β-hexosaminidase in serum from hemolyzed blood.

    Science.gov (United States)

    Chojnowska, Sylwia; Kępka, Alina; Szajda, Sławomir Dariusz; Kołodziejczyk, Zbigniew Paweł; Zwierz, Krzysztof; Waszkiewicz, Napoleon

    2016-07-01

    Determination of lysosomal N-acetyl-β-hexosaminidase (HEX) in serum from hemolyzed blood, creates serious analytical problems, because hemoglobin absorbs light at a similar wavelength like 4-nitrophenol, which is released from artificial substrate. The objective of the work was to adapt a manual method to allow analysis of HEX in hemolyzed samples. Serums without and with hemolysis were incubated with 4-nitrophenol-N-acetylglucosamine as a substrate. Released 4-nitrophenol was determined colorimetrically. After the incubation of the serum from hemolyzed blood with substrate, hemoglobin was precipitated with trichloroacetic acid (TCA) before 4-nitrophenol determination. The mean concentration of HEX activity in non-hemolyzed and hemolyzed blood of the same patients, determined with non-modified and modified methods had no significant differences, and they are: 243.12±119.76 and 233.99±108.76pkat/mL, respectively. A coefficient of correlation between non-modified and modified methods equals the 0.98. For HEX determination with the modified method in serum from hemolyzed blood, optimal reaction time was 60min, pH of reaction mixture was 4.7, and Km was 0.11mMm. HEX determinations in the same serums from non-hemolyzed blood by the non-modified method and hemolyzed blood with the modified method, gave similar results with a 0.98 coefficient of correlation. The modified method is appropriate for HEX determination in serum from hemolyzed blood. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  17. Effect of oral N-acetyl cysteine on eradication of Helicobacter pylori in patients with dyspepsia.

    Science.gov (United States)

    Karbasi, A; Hossein Hosseini, S; Shohrati, M; Amini, M; Najafian, B

    2013-03-01

    Using mucolytic agents that decrease viscosity of the gastric mucous and therefore, increase the permeability of antibiotics through gastric membrane has been offered as an additive treatment to achieve a higher rate of eradication of Helicobacter pylori (H. Pylori) infection. The aim of this study was to determine the efficacy of oral N-acetyl cysteine (NAC) on eradication of H. pylori infections in patients suffering from dyspepsia. In this randomized double-blinded clinical trial, 60 H. pylori positive patients who were suffering from dyspepsia were included. They were divided into two groups. Both groups received three-drug regimen including pantoprazole 40 mg BD, ciprofloxacin 500 mg BD and bismuth subcitrate 120 mg two tablets BD. Experimental group (30 cases) received 600 mg of NAC besides three-drug regimen. Control group received placebo. The results of therapy were tested by 14C-UBT and were compared with each other two months after the first visit. H. pylori infection was eradicated in 21 (70%) and 17 (60.7%) patients in experimental and control groups, respectively (P=0.526). Regarding clinical and endoscopic variables, no significant difference was observed between the two groups except for erosive gastritis (0.041) and erosive esophagitis (0.031). Our findings offer that NAC has an additive effect on H. pylori triple therapy with pantoprazole, ciprofloxacin and bismuth subcitrate. Although NAC does not have any known activity against H. pylori, it can reduce the thickness of the mucus layer and increase the permeability of antibiotics at the site of infection. To evaluate this effect, more studies with larger sample size should be performed.

  18. A Preliminary Study: N-acetyl-L-cysteine Improves Semen Quality following Varicocelectomy

    Directory of Open Access Journals (Sweden)

    Foroogh Barekat

    2016-05-01

    Full Text Available Background: Surgery is considered the primary treatment for male infertility from clinical varicocele. One of the main events associated with varicocele is excessive production of reactive oxygen species (ROS. N-acetyl-L-cysteine (NAC, an antioxidant that scavenges free radicals, is considered a supplement to alleviate glutathione (GSH depletion during oxidative stress. Despite beneficial effects of NAC in other pathological events, there is no report on the effect of NAC in individuals with varicocele. Therefore, the aim of this study is to evaluate the outcome of NAC on semen quality, protamine content, DNA damage, oxidative stress and fertility following varicocelectomy. Materials and Methods: This prospective clinical trial included 35 infertile men with varicocele randomly divided into control (n=20 and NAC (n=15 groups. We assessed semen parameters, protamine content [chromomycin A3 (CMA3], DNA integrity [terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling (TUNEL] and oxidative stress [2', 7'-dichlorodihydrofluorescein-diacetate (DCFH-DA] before and three months after varicocelectomy. Results: Percentage of abnormal semen parameters, protamine deficiency, DNA fragmentation and oxidative stress were significantly decreased in both groups compared to before surgery. We calculated the percentage of improvement in these parameters compared to before surgery for each group, then compared the results between the groups. Only percentage of protamine deficiency and DNA fragmentation significantly differed between the NAC and control groups. Conclusion: The results of this study, for the first time, revealed that NAC improved chromatin integrity and pregnancy rate when administered as adjunct therapy post-varicocelectomy (Registeration Number: IRCT201508177223N5.

  19. Associations between diffusion and perfusion parameters, N-acetyl aspartate, and lactate in acute ischemic stroke.

    Science.gov (United States)

    Cvoro, Vera; Wardlaw, Joanna M; Marshall, Ian; Armitage, Paul A; Rivers, Carly S; Bastin, Mark E; Carpenter, Trevor K; Wartolowska, Karolina; Farrall, Andrew J; Dennis, Martin S

    2009-03-01

    In acute ischemic stroke, the amount of neuronal damage in hyperintense areas on MR diffusion imaging (DWI) is unclear. We used spectroscopic imaging to measure N-acetyl aspartate (NAA, a marker of normal neurons) and lactate (a marker of ischemia) to compare with diffusion and perfusion values in the diffusion lesion in acute ischemic stroke. We recruited patients with acute ischemic stroke prospectively and performed MR diffusion weighted (DWI), perfusion, and spectroscopic imaging. We coregistered the images, outlined the visible diffusion lesion, and extracted metabolite, perfusion, and apparent diffusion coefficient (ADC) values from the diffusion lesion. 42 patients were imaged, from 1.5 to 24 hours after stroke. In the DWI lesion, although NAA was reduced, there was no correlation between NAA and ADC or perfusion values. However, raised lactate correlated with reduced ADC (Spearman rho=0.32, P=0.04) and prolonged mean transit time (MTT, rho=0.31, P=0.04). Increasing DWI lesion size was associated with lower NAA and higher lactate (rho=-0.44, P=0.003; rho=0.49, P=0.001 respectively); NAA fell with increasing times to imaging (rho=-0.3, P=0.03), but lactate did not change. Although larger confirmatory studies are needed, the correlation of ADC and MTT with lactate but not NAA suggests that ADC and MTT are better markers of the presence of ischemia than of cumulative neuronal loss. Further studies should define more precisely the rate of neuronal loss and relationship to diffusion and perfusion parameters with respect to the depth and duration of ischemia.

  20. Nanostructured Lipid Carrier for Topical Application of N-Acetyl Glucosamine

    Directory of Open Access Journals (Sweden)

    Lavin Aliasgharlou

    2016-12-01

    Full Text Available Purpose: Hyperpigmentation occurs when melanin is overproduced in certain spots on the skin and is one of the most challenging skin conditions to treat. Although it is usually harmless, for cosmetic reasons, it is dreadfully bothersome to those who undergo it. It was reported that N-acetyl-glucosamine (NAGA prevents melanin synthesis and alters the expression of numerous genes related to pigmentation. In spite of these advantages, NAGA cannot be employed in topical formulations due to its extremely polar characteristics. Nanoparticles, especially lipid-based ones, have been introduced as an efficient carrier for dermal drug delivery. Methods: The aim of the present study was to load adequate hydrophilic NAGA to the lipophilic nanostructured lipid carriers (NLCs for potential dermal application. Methods: NAGA-loaded NLCs were formulated, using hot homogenization technique, and the characteristics of the optimized formulation were analyzed by laser light scattering, X-ray diffraction, and scanning electron microscopy methods. Loading capacity percentage and in vitro release study were carried out by applying a validated HPLC method. The optimum formulation was utilized for the in vivo skin lightening evaluations in healthy volunteers. Results: NAGA-loaded NLCs demonstrated promising results (the size of 190 nm, narrow size distribution, loading capacity of 9%, and appropriate NAGA release profile suitable for dermal delivery. XRD results exhibited a dramatic reduction in the crystalline structure of encapsulated NAGA. Dermoscopy images indicated a considerable decline in melanin distribution pattern in the majority of the cases treated with NAGA-loaded NLCs. Conclusion: Thus, this study has opened new horizons for the potential use of lipid based nanoparticles in the managing of hyperpigmentation.

  1. Formation of three N-acetyl-L-cysteine monoadducts and one diadduct by the reaction of S-(1,2-dichlorovinyl)-L-cysteine sulfoxide with N-acetyl-L-cysteine at physiological conditions: chemical mechanisms and toxicological implications.

    Science.gov (United States)

    Barshteyn, Nella; Elfarra, Adnan A

    2007-10-01

    Previously, our laboratory has shown that S-(1,2-dichlorovinyl)-L-cysteine sulfoxide (DCVCS), a Michael acceptor produced by a flavin-containing monooxygenase 3 (FMO3)-mediated oxidation of S-(1,2-dichlorovinyl)-L-cysteine (DCVC), is a more potent nephrotoxicant than DCVC. In the present study, we characterized reactions of DCVCS with nucleophilic amino acids. DCVCS incubations with N-acetyl-L-cysteine (NAC) at pH 7.4 and 37 degrees C for 1 h resulted in the formation of three monoadducts and one diadduct characterized by LC/MS, 1H NMR, and 1H-detected heteronuclear single quantum correlation. The formation of all adducts (with relative ratios of 29, 31, 24, and 12%, respectively) was rapid and time-dependent; the half-lives of the two DCVCS diastereomers in the presence of NAC were 13.8 (diastereomer I) and 9.4 min (diastereomer II). Adducts 1 and 2 were determined to be diastereomers of S-[1-chloro-2-(N-acetyl-L-cystein- S-yl)vinyl]-L-cysteine sulfoxide formed by Michael addition of NAC to the terminal vinylic carbon of DCVCS followed by loss of HCl. Adduct 4 was determined to be S-[2-chloro-2-(N-acetyl-L-cystein- S-yl)vinyl]-L-cysteine sulfoxide formed from the initial Michael addition product followed by a less favorable loss of HCl and/or by a rearrangement of adduct 2 through the formation of a cyclic chloronium ion. The addition of another molecule of NAC to monoadducts 1, 2, or 4 resulted in the formation of the novel diadduct, S-[2,2-( N-acetyl-L-cystein-S-yl)vinyl]-L-cysteine sulfoxide (adduct 3), whose detection in relatively large amount suggests that DCVCS could act as a cross-linking agent. DCVCS was not reactive with N-acetyl-L-lysine or L-valinamide at similar incubation conditions. Collectively, the results suggest selective reactivity of DCVCS toward protein sulfhydryl groups. Furthermore, the cross-linking properties of DCVCS may in part explain its high nephrotoxic potency.

  2. Hydration and N-acetyl-l-cysteine alter the microstructure of human nail and bovine hoof: implications for drug delivery.

    Science.gov (United States)

    Nogueiras-Nieto, L; Gómez-Amoza, J L; Delgado-Charro, M B; Otero-Espinar, F J

    2011-12-20

    This work aimed to (a) characterize the microstructure and porosity of human nail and bovine hoof by mercury intrusion porosimetry and SEM image analysis, (b) study the effects of hydration and of N-acetyl-l-cysteine treatment on the microstructure of both membranes, and (c) determine whether the microstructural modifications were associated with changes in drug penetration measured by standard diffusion studies. Bovine hoof surface is more porous than nail surface although there were no differences between the mean surface pore sizes. Hydration and N-acetyl-l-cysteine increased the roughness and apparent surface porosity, and the porosity determined by mercury intrusion porosimetry of both membranes. Pore-Cor™ was used to generate tridimensional structures having percolation characteristics comparable to nail and hooves. The modeled structures were horizontally banded having an inner less-porous area which disappeared upon treatment. Treatment increased the predicted permeability of the simulated structures. Triamcinolone permeation increased significantly for hooves treated N-acetyl-l-cysteine, i.e., the membranes for which microstructural and permeability changes were the largest. Thus, microstructural changes determined via mercury intrusion porosimetry and subsequently modeled by Pore-Cor™ were related to drug diffusion. Further refinement of the technique will allow fast screening of penetration enhancers to be used in ungual drug delivery. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Distinct roles of N-acetyl and 5-methoxy groups in the antiproliferative and neuroprotective effects of melatonin.

    Science.gov (United States)

    Letra-Vilela, Ricardo; Sánchez-Sánchez, Ana María; Rocha, Ana Maia; Martin, Vanesa; Branco-Santos, Joana; Puente-Moncada, Noelia; Santa-Marta, Mariana; Outeiro, Tiago Fleming; Antolín, Isaac; Rodriguez, Carmen; Herrera, Federico

    2016-10-15

    Melatonin (N-acetyl-5-methoxytryptamine) is a highly pleiotropic hormone with antioxidant, antiproliferative, oncolytic and neuroprotective properties. Here, we present evidence that the N-acetyl side chain plays a key role in melatonin's antiproliferative effect in HT22 and sw-1353 cells, but it does so at the expense of antioxidant and neuroprotective properties. Removal of the N-acetyl group enhances the antioxidant and neuroprotective properties of the indole, but it can lead to toxic methamphetamine-like effects in several cell lines. Inhibition of NFkB mimicked melatonin's antiproliferative and antioxidant effects, but not neuroprotection. Our results strongly suggest that neuroprotective and antiproliferative effects of melatonin rely on different parts of the molecule and are likely mediated by different mechanisms. We also predict that melatonin metabolism by target cells could determine whether melatonin inhibits cell proliferation, prevents toxicity or induces cell death (e.g. apoptosis or autophagy). These observations could have important implications for the rational use of melatonin in personalized medicine.

  4. Maize root lectins mediate the interaction with Herbaspirillum seropedicae via N-acetyl glucosamine residues of lipopolysaccharides.

    Science.gov (United States)

    Balsanelli, Eduardo; Tuleski, Thalita Regina; de Baura, Valter Antonio; Yates, Marshall Geoffrey; Chubatsu, Leda Satie; Pedrosa, Fabio de Oliveira; de Souza, Emanuel Maltempi; Monteiro, Rose Adele

    2013-01-01

    Herbaspirillum seropedicae is a plant growth-promoting diazotrophic betaproteobacterium which associates with important crops, such as maize, wheat, rice and sugar-cane. We have previously reported that intact lipopolysaccharide (LPS) is required for H. seropedicae attachment and endophytic colonization of maize roots. In this study, we present evidence that the LPS biosynthesis gene waaL (codes for the O-antigen ligase) is induced during rhizosphere colonization by H. seropedicae. Furthermore a waaL mutant strain lacking the O-antigen portion of the LPS is severely impaired in colonization. Since N-acetyl glucosamine inhibits H. seropedicae attachment to maize roots, lectin-like proteins from maize roots (MRLs) were isolated and mass spectrometry (MS) analysis showed that MRL-1 and MRL-2 correspond to maize proteins with a jacalin-like lectin domain, while MRL-3 contains a B-chain lectin domain. These proteins showed agglutination activity against wild type H. seropedicae, but failed to agglutinate the waaL mutant strain. The agglutination reaction was severely diminished in the presence of N-acetyl glucosamine. Moreover addition of the MRL proteins as competitors in H. seropedicae attachment assays decreased 80-fold the adhesion of the wild type to maize roots. The results suggest that N-acetyl glucosamine residues of the LPS O-antigen bind to maize root lectins, an essential step for efficient bacterial attachment and colonization.

  5. Maize root lectins mediate the interaction with Herbaspirillum seropedicae via N-acetyl glucosamine residues of lipopolysaccharides.

    Directory of Open Access Journals (Sweden)

    Eduardo Balsanelli

    Full Text Available Herbaspirillum seropedicae is a plant growth-promoting diazotrophic betaproteobacterium which associates with important crops, such as maize, wheat, rice and sugar-cane. We have previously reported that intact lipopolysaccharide (LPS is required for H. seropedicae attachment and endophytic colonization of maize roots. In this study, we present evidence that the LPS biosynthesis gene waaL (codes for the O-antigen ligase is induced during rhizosphere colonization by H. seropedicae. Furthermore a waaL mutant strain lacking the O-antigen portion of the LPS is severely impaired in colonization. Since N-acetyl glucosamine inhibits H. seropedicae attachment to maize roots, lectin-like proteins from maize roots (MRLs were isolated and mass spectrometry (MS analysis showed that MRL-1 and MRL-2 correspond to maize proteins with a jacalin-like lectin domain, while MRL-3 contains a B-chain lectin domain. These proteins showed agglutination activity against wild type H. seropedicae, but failed to agglutinate the waaL mutant strain. The agglutination reaction was severely diminished in the presence of N-acetyl glucosamine. Moreover addition of the MRL proteins as competitors in H. seropedicae attachment assays decreased 80-fold the adhesion of the wild type to maize roots. The results suggest that N-acetyl glucosamine residues of the LPS O-antigen bind to maize root lectins, an essential step for efficient bacterial attachment and colonization.

  6. Melatonin and N-acetyl-serotonin cross the red blood cell membrane and evoke calcium mobilization in malarial parasites

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    Hotta C.T.

    2003-01-01

    Full Text Available The duration of the intraerythrocytic cycle of Plasmodium is a key factor in the pathogenicity of this parasite. The simultaneous attack of the host red blood cells by the parasites depends on the synchronicity of their development. Unraveling the signals at the basis of this synchronicity represents a challenging biological question and may be very important to develop alternative strategies for therapeutic approaches. Recently, we reported that the synchrony of Plasmodium is modulated by melatonin, a host hormone that is synthesized only during the dark phases. Here we report that N-acetyl-serotonin, a melatonin precursor, also releases Ca2+ from isolated P. chabaudi parasites at micro- and nanomolar concentrations and that the release is blocked by 250 mM luzindole, an antagonist of melatonin receptors, and 20 mM U73122, a phospholipase C inhibitor. On the basis of confocal microscopy, we also report the ability of 0.1 µM melatonin and 0.1 µM N-acetyl-serotonin to cross the red blood cell membrane and to mobilize intracellular calcium in parasites previously loaded with the fluorescent calcium indicator Fluo-3 AM. The present data represent a step forward into the understanding of the signal transduction process in the host-parasite relationship by supporting the idea that the host hormone melatonin and N-acetyl-serotonin generate IP3 and therefore mobilize intracellular Ca2+ in Plasmodium inside red blood cells.

  7. Mechanism of activation of mouse liver microsomal glutations S—transferase by paracetamol treatment

    Institute of Scientific and Technical Information of China (English)

    ZhenY; LouYJ

    2002-01-01

    Microsomal glutathion S-transferase(mGST) is one of the important detoxifcation enzymes in vivo,its modifying activation by drugs has been paid more attention to in pertinent field recently.This study was to explore the influence of paracetamol(Par) on mGST and its possible mechanism in vivo,and to further reveal the biological significance.Par is metabolized to N-acetyl-p-benzoquinone imine(NAPQI) by CYP2E1 and mGST is activated by sulfhydryl modification.

  8. Long-Time Treatment by Low-Dose N-Acetyl-L-Cysteine Enhances Proinflammatory Cytokine Expressions in LPS-Stimulated Macrophages

    OpenAIRE

    Tomokazu Ohnishi; Kenjiro Bandow; Kyoko Kakimoto; Joji Kusuyama; Tetsuya Matsuguchi

    2014-01-01

    N-acetyl-L-cysteine is known to act as a reactive oxygen species scavenger and used in clinical applications. Previous reports have shown that high-dose N-acetyl-L-cysteine treatment inhibits the expression of proinflammatory cytokines in activated macrophages. Here, we have found that long-time N-acetyl-L-cysteine treatment at low-concentration increases phosphorylation of extracellular signal-regulated kinase 1/2 and AKT, which are essential for the induction of proinflammatory cytokines in...

  9. L-cysteine, N-acetyl-L-cysteine, and glutathione protect Xenopus laevis embryos against acrylamide-induced malformations and mortality in the frog embryo teratogenesis assay.

    Science.gov (United States)

    Rayburn, James R; Friedman, Mendel

    2010-10-27

    Dietary acrylamide is largely derived from heat-induced reactions between the amino group of the free amino acid asparagine and carbonyl groups of glucose and fructose during heat processing (baking, frying) of plant-derived foods such as potato fries and cereals. After consumption, acrylamide is absorbed into the circulation and is then distributed to various organs, where it can react with DNA, neurons, hemoglobin, and essential enzymes. In the present study, we explored the potential of L-cysteine (CySH), N-acetyl-L-cysteine (NAC), reduced glutathione (GSH), and the amino acid glycine (Gly) to protect frog embryos against acrylamide-induced developmental toxicity in the frog embryo teratogenesis assay - Xenopus (FETAX). To test the antiteratogenic potential, based on concentration-response study ranging from 0.07 to 4.22 mM acrylamide in FETAX solution (pH 8.1), we selected concentrations of acrylamide that induced 100% malformations and mortality. At the end of 96 h, we counted survivors and malformed embryos and measured embryo length. The data show that CySH, NAC, and GSH protected the embryos against acrylamide induced malformations and mortality to different degrees. CySH and GSH protected the embryos against both malformations and mortality, whereas NAC protected only against mortality. Gly had no protective effect. Possible mechanisms of the protective effects and the dietary significance of the results of this and related studies for food safety and human health are discussed.

  10. Long-time treatment by low-dose N-acetyl-L-cysteine enhances proinflammatory cytokine expressions in LPS-stimulated macrophages.

    Directory of Open Access Journals (Sweden)

    Tomokazu Ohnishi

    Full Text Available N-acetyl-L-cysteine is known to act as a reactive oxygen species scavenger and used in clinical applications. Previous reports have shown that high-dose N-acetyl-L-cysteine treatment inhibits the expression of proinflammatory cytokines in activated macrophages. Here, we have found that long-time N-acetyl-L-cysteine treatment at low-concentration increases phosphorylation of extracellular signal-regulated kinase 1/2 and AKT, which are essential for the induction of proinflammatory cytokines including interleukin 1β and interleukin 6 in lipopolysaccharide-stimulated RAW264.7 cells. Furthermore, long-time N-acetyl-L-cysteine treatment decreases expressions of protein phosphatases, catalytic subunit of protein phosphatase-2A and dual specificity phosphatase 1. On the other hand, we have found that short-time N-acetyl-L-cysteine treatment at low dose increases p53 expression, which inhibits expressions of proinflammatory cytokines. These observations suggest that long-time low-dose N-acetyl-L-cysteine treatment increases expressions of proinflammatory cytokines through enhancement of kinase phosphorylation.

  11. Crystal structure of product-bound complex of UDP-N-acetyl-D-mannosamine dehydrogenase from Pyrococcus horikoshii OT3

    Energy Technology Data Exchange (ETDEWEB)

    Pampa, K.J., E-mail: sagarikakj@gmail.com [Department of Studies in Microbiology, University of Mysore, Mysore 570 006 (India); Lokanath, N.K. [Department of Studies in Physics, University of Mysore, Mysore 570 006 (India); Girish, T.U. [Department of General Surgery, JSS Medical College and Hospital, JSS University, Mysore 570 015 (India); Kunishima, N. [Advanced Protein Crystallography Research Group, RIKEN SPring-8 Center, Harima Institute, Hyogo 679-5148 (Japan); Rai, V.R. [Department of Studies in Microbiology, University of Mysore, Mysore 570 006 (India)

    2014-10-24

    Highlights: • Determined the structure of UDP-D-ManNAcADH to a resolution of 1.55 Å. • First complex structure of PhUDP-D-ManNAcADH with UDP-D-ManMAcA. • The monomeric structure consists of three distinct domains. • Cys258 acting as catalytic nucleophilic and Lys204 acts as acid/base catalyst. • Oligomeric state plays an important role for the catalytic function. - Abstract: UDP-N-acetyl-D-mannosamine dehydrogenase (UDP-D-ManNAcDH) belongs to UDP-glucose/GDP-mannose dehydrogenase family and catalyzes Uridine-diphospho-N-acetyl-D-mannosamine (UDP-D-ManNAc) to Uridine-diphospho-N-acetyl-D-mannosaminuronic acid (UDP-D-ManNAcA) through twofold oxidation of NAD{sup +}. In order to reveal the structural features of the Pyrococcus horikoshii UDP-D-ManNAcADH, we have determined the crystal structure of the product-bound enzyme by X-ray diffraction to resolution of 1.55 Å. The protomer folds into three distinct domains; nucleotide binding domain (NBD), substrate binding domain (SBD) and oligomerization domain (OD, involved in the dimerization). The clear electron density of the UDP-D-ManNAcA is observed and the residues binding are identified for the first time. Crystal structures reveal a tight dimeric polymer chains with product-bound in all the structures. The catalytic residues Cys258 and Lys204 are conserved. The Cys258 acts as catalytic nucleophile and Lys204 as acid/base catalyst. The product is directly interacts with residues Arg211, Thr249, Arg244, Gly255, Arg289, Lys319 and Arg398. In addition, the structural parameters responsible for thermostability and oligomerization of the three dimensional structure are analyzed.

  12. Isoenzymes A and B of N-acetyl-beta-D-hexosaminidase in serum and urine of patients with pancreatic cancer.

    Science.gov (United States)

    Szajda, Slawomir Dariusz; Snarska, Jadwiga; Jankowska, Anna; Puchalski, Zbigniew; Zwierz, Krzysztof

    2008-01-01

    Adenocarcinoma is the most frequent malignant tumor of the pancreas. Biochemical diagnostics of pancreatic adenocarcinoma is based on determination of carcinoma antigen (CA 19-9) in the blood. Determination of N-acetyl-beta-hexosaminidase (HEX) in the serum and urine was used in diagnosis of renal and gastric cancers. Therefore the aim of our research was to estimate N-acetyl-beta-hexosaminidase (HEX) and its isoenzymes (HEX A and HEX B) in the serum and urine as potential markers of pancreatic cancer. Serum and urine samples were collected from 15 patients with adenocarcinoma of the pancreas and 15 healthy persons. The activity of N-acetyl-beta-hexosaminidase and its isoenzymes (A and B) was determined by a colorimetric method of Zwierz et al. Absorbancy of the yellow product of the colorimetric reaction was determined on the microplate reader EL(x)800 produced by BIO-TEK. The concentration of HEX, HEX A and B was expressed in pKat/mL, and the specific activity in pKat/mg of protein. Protein concentration was determined in the serum by the biuret and in the urine by the Lowry method, respectively, and expressed in mg/mL. The concentration and specific activity of HEX and its isoenzyme A were significantly higher in the serum and urine of pancreatic cancer patients in comparison with the concentration and specific activity in the serum and urine of healthy people. The results suggest that the activity of HEX and its isoenzyme A determined in the serum and urine can be used as a potential marker of pancreatic adenocarcinoma.

  13. Recognition of chitooligosaccharides and their N-acetyl groups by putative subsites of chitin deacetylase from a deuteromycete, Colletotrichum lindemuthianum.

    Science.gov (United States)

    Tokuyasu, K; Mitsutomi, M; Yamaguchi, I; Hayashi, K; Mori, Y

    2000-08-01

    The reaction pattern of an extracellular chitin deacetylase from a Deuteromycete, Colletotrichum lindemuthianum ATCC 56676, was investigated by use of chitooligosaccharides [(GlcNAc)(n)(), n = 3-6] and partially N-deacetylated chitooligosaccharides as substrates. When 0.5% of (GlcNAc)(n)() was deacetylated, the corresponding monodeacetylated products were initially detected without any processivity, suggesting the involvement of a multiple-chain mechanism for the deacetylation reaction. The structural analysis of these first-step products indicated that the chitin deacetylase strongly recognizes a sequence of four N-acetyl-D-glucosamine (GlcNAc) residues of the substrate (the subsites for the four GlcNAc residues are defined as -2, -1, 0, and +1, respectively, from the nonreducing end to the reducing end), and the N-acetyl group in the GlcNAc residue positioned at subsite 0 is exclusively deacetylated. When substrates of a low concentration (100 microM) were deacetylated, the initial deacetylation rate for (GlcNAc)(4) was comparable to that of (GlcNAc)(5), while deacetylation of (GlcNAc)(3) could not be detected. Reaction rate analyses of partially N-deacetylated chitooligosaccharides suggested that subsite -2 strongly recognizes the N-acetyl group of the GlcNAc residue of the substrate, while the deacetylation rate was not affected when either subsite -1 or +1 was occupied with a D-glucosamine residue instead of GlcNAc residue. Thus, the reaction pattern of the chitin deacetylase is completely distinct from that of a Zygomycete, Mucor rouxii, which produces a chitin deacetylase for accumulation of chitosan in its cell wall.

  14. Effectiveness of Oral N-acetyl-cystein in Reduction of Pulmonary Complications in Smokers Undergoing Coronary Artery Bypass Surgery

    Directory of Open Access Journals (Sweden)

    SJ Mir Hoseini

    2009-10-01

    Full Text Available Introduction: Up to 12% of patients undergoing coronary artery bypass graft have pulmonary complications. Smoking can cause a six-time increase in pulmonary complication after major surgery. The most common pulmonary changes after CABG are decrease in FRC, VC and atelectasis. In this study, the effect of oral N-acetyl-cystein in reduction of severity of hypoxemia and atelectasis in current smokers who smoked more than 10 packs/year and had undergone CABG was evaluated. Methods: In the study, 54 current smoker patients were selected randomly and allocated to two drug and placebo groups. In the study group, 300mg N-acetyl-cystein (ACC long containing vitamin C was prescribed two times a day from 4 days before operation up to 3 days after surgery and in control group, effervescent vitamin C tablet was prescribed as placebo. Patients with body mass index more than 35, NYHA class IV, those who needed intra aortic balloon pump and those who needed reoperation due to bleeding were excluded from the study. In all patients, spirometry was done in the preoperative visit and FEV1/FVC was determined. Induction and maintenance of anesthesia was similar in all patients. Arterial blood gas samples were obtained immediately after anesthesia induction and 4 to 6 hours after extubation. Chest X ray was taken before, 6 to 10 hours after extubation and 3rd postoperative day. Severity of atelectasis was also measured. Quantitative & qualitative data was analyzed by ANOVA and Chi-square tests, respectively. Pvalue<0.05 was considered as statistically significant. Results: Both groups were similar with respect to demographic data including ejection fraction, NYHA class, FEV1/FVC, cigarette smoking and Lima harvesting. The ratio of arterial oxygen pressure to fraction of inspiratory oxygen Pao2/FIo2 was not significantly different after induction but this difference was strongly significant (Pvalue<0.005 after extubation. Duration of mechanical ventilation was

  15. Beneficial effects of n-acetyl cysteine on pancreas and kidney following experimental pancreatic ischemia-reperfusion in rats

    Directory of Open Access Journals (Sweden)

    Roberto Ferreira Meirelles Junior

    2010-01-01

    Full Text Available OBJECTIVE: To evaluate the protective effects of N-acetyl cysteine on the pancreas and kidney after pancreatic ischemia reperfusion injury in a rat model. METHODS AND MATERIALS: Pancreatic ischemia reperfusion was performed in Wistar rats for 1 hour. Revascularization was achieved followed by 4 h of reperfusion. A total of 24 animals were divided into four groups: Group 1: sham; Group 2: pancreatic ischemia reperfusion without treatment; Group 3: pancreatic ischemia reperfusion plus N-acetyl cysteine intravenously; and Group 4: pancreatic ischemia reperfusion plus N-acetyl cysteine per os. Blood and tissue samples were collected after reperfusion. RESULTS: There were significant differences in amylase levels between Group 1 (6.11±0.55 and Group 2 (10.30±0.50 [p=0.0002] as well as between Group 2 (10.30±0.50 and Group 4 (7.82±0.38 [p=0.003]; creatinine levels between Group 1 (0.52 ± 0.07 and Group 2 (0.77±0.18 [p=0.035] as well as between Group 2 (0.77±0.18 and Group 3 (0.48±0.13 [p=0.012]; and pancreatic tissue thiobarbituric acid reactive substance levels between Group 1 (1.27±0.96 and Group 2 (2.60±3.01 [p=0.026] as well as between Group 2 (2.60±3.01 and Group 4 (0.52±0.56 [p=0.002]. A decrease in pancreatic tissue GST-α3 gene expression was observed in Group 2 in comparison to Group 1 (p =0.006, and an increase was observed in Groups 3 and 4 when compared to Group 2 (p= 0.025 and p=0.010, respectively. CONCLUSION: This study provides evidence that N-acetyl cysteine has a beneficial effect on pancreatic ischemia reperfusion injury and renal function in a rat model.

  16. Simultaneous measurement of N-Acetyl-S-(2-cyanoethyl)-cysteine and N-acetyl-S-(2-hydroxyethyl)-cysteine in human urine by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Xiaotao, Zhang; Hongwei, Hou; Wei, Xiong; Qingyuan, Hu

    2014-08-01

    Acrylonitrile, possibly carcinogenic to humans, is mainly present in tobacco smoke and undergoes metabolism to form N-acetyl-S-(2-cyanoethyl)-cysteine (CEMA) and N-acetyl-S-(2-hydroxyethyl)-cysteine (HEMA). A method based on the direct dilution to simultaneously identify and quantify CEMA and HEMA in human urine by rapid resolution liquid chromatography-electrospray ionization tandem mass spectrometry (RRLC-MS-MS) was validated for assessing smoking-related acrylonitrile exposure. The recovery rates of the whole analytical procedure were 98.2-106.0% and 97.1-112.7% for HEMA and CEMA, respectively. The linear range of standard solutions was 0.5-100.0 ng/mL for CEMA and was 0.2-40.0 ng/mL for HEMA. RRLC using a small particle size column was combined with a tandem mass spectrometry system, which lowered the detection limit of analytes, reduced the ion suppression of mass and shortened the analysis time. The proposed method was successfully applied for the analysis of 126 urine samples from smokers and nonsmokers.

  17. Clonal analysis of a human lymphoblastoid cell line (B17) secreting antibody to N-acetyl-D-glucosamine.

    Science.gov (United States)

    Polke, C; Greger, B; Steinitz, M; Eichmann, K

    1982-10-01

    In this paper we analyse the clonal composition of a human lymphoblastoid B-cell line secreting IgM/k antibody to N-acetyl-D-glucosamine, the immunodominant sugar of Group-A-streptococcal carbohydrate. Besides non-antibody secreting cells, the line consists of two clonotypes of antibody-secreting cells: B17 cells producing over 90% and F6 cells producing less than 10% of the antibody in the supernatant. The proportions of B17 and F6 cells in the cell line seem to be similar to the proportion of antibodies in the supernatant. F6 cells can be isolated by cloning and maintained as stable lines, whereas this is more difficult with B17 cells. The results suggest that upon establishment of the line, at least two N-acetyl-D-glucosamine-specific B cells were immortalized and coexist together as independent clonotypes. Although F6 cells seem to have a slight tissue culture advantage, they represent the minor clonotype in the B17 cell line.

  18. Modulatory effects of curcumin and green tea extract against experimentally induced pulmonary fibrosis: a comparison with N-acetyl cysteine.

    Science.gov (United States)

    Hamdy, Mohammed Ahmed; El-Maraghy, Shohda A; Kortam, Mona Abd El Aziz

    2012-11-01

    The study was aimed to investigate the protective effect of green tea extract (GTE), curcumin, and N-acetyl cysteine (NAC) on experimentally induced pulmonary fibrosis. Curcumin (200 mg/kg b.w), GTE (150 mg/kg b.w), and NAC (490 mg/kg b.w) were administered orally for 14 days with concomitant administration of cyclophosphamide (CP). Lung fibrosis was assessed by measuring hydroxyproline and elastin levels and confirmed by histopathological examination. Oxidative stress was also observed in the CP group. Lung myeloperoxidase activity was significantly decreased in animals of the CP group. N-acetyl-β-d-glucosaminidase, leukotriene C₄, and protein were increased in bronchoalveolar lavage fluid (BALF). Transforming growth factor-β, interleukin -1β, and histamine were increased in both serum and BALF. All modulators markedly attenuated the altered biochemical parameters as compared to CP-treated rats. These results suggest the possibility of using these treatments as protective agents with chemotherapy and as protective agents for lung fibrosis.

  19. N-Acetylation of p-aminobenzoic acid and p-phenylenediamine in primary porcine urinary bladder epithelial cells and in the human urothelial cell line 5637.

    Science.gov (United States)

    Föllmann, Wolfram; Blaszkewicz, Meinolf; Behm, Claudia; Degen, Gisela H; Golka, Klaus

    2012-01-01

    N-Acetyltransferases (NAT) are important enzymes in the metabolism of certain carcinogenic arylamines, as N-acetylation decreases or prevents their bioactivation via N-hydroxylation. To study such processes in the bladder, cell culture models may be used, but metabolic competence needs to be characterized. This study focused on the N-acetylation capacity of two urothelial cell systems, using p-aminobenzoic acid (PABA) and the hair dye precursor p-phenylenediamine (PPD), two well-known substrates of the enzyme NAT1. The constitutive NAT1 activity was investigated using primary cultures of porcine urinary bladder epithelial cells (PUBEC) and in the human urothelial cell line 5637 to assess their suitability for further in vitro studies on PABA and PPD-induced toxicity. N-Acetylation of PABA and PPD was determined by high-performance liquid chromatography (HPLC) analysis in cytosols of the two cell systems upon incubation with various substrate levels for up to 60 min. The primary PUBEC revealed higher N-acetylation rates (2.5-fold for PABA, 5-fold for PPD) compared to the 5637 cell line, based on both PABA conversion to its acetylated metabolite and formation of mono- and diacetylated PPD. The urothelial cell systems may thus be useful as a tool for further studies on the N-acetylation of aromatic amines via NAT1.

  20. Rats with metabolic syndrome resist the protective effects of N-acetyl l-cystein against impaired spermatogenesis induced by high-phosphorus/zinc-free diet.

    Science.gov (United States)

    Suzuki, Yuka; Ichihara, Gaku; Sahabudeen, Sheik Mohideen; Kato, Ai; Yamaguchi, Takanori; Imanaka-Yoshida, Kyoko; Yoshida, Toshimichi; Yamada, Yoshiji; Ichihara, Sahoko

    2013-11-01

    Consumption of relatively high amounts of processed food can result in abnormal nutritional status, such as zinc deficiency or phosphorus excess. Moreover, hyperphosphatemia and hypozincemia are found in some patients with diabetic nephropathy and metabolic syndrome. The present study investigated the effects of high-phosphorus/zinc-free diet on the reproductive function of spontaneously hypertensive rats/NDmcr-cp (SHR/cp), a model of the metabolic syndrome. We also investigated the effects of antioxidant, N-acetyl-l-cysteine (NAC), on testicular dysfunction under such conditions. Male SHR/cp and control rats (Wistar Kyoto rats, WKY) were divided into three groups; rats fed control diet (P 0.3%, w/w; Zn 0.2%, w/w), high-phosphorus and zinc-deficient diet (P 1.2%, w/w; Zn 0.0%, w/w) with vehicle, or high-phosphorus and zinc-deficient diet with NAC (1.5mg/g/day) for 12 weeks (n=6 or 8 rats/group). The weights of testis and epididymis were significantly reduced by high-phosphate/zinc-free diet in both SHR/cp and WKY. The same diet significantly reduced caudal epididymal sperm count and motility and induced histopathological changes in the testis in both strains. Treatment with NAC provided significant protection against the toxic effects of the diet on testicular function in WKY, but not in SHR/cp. The lack of the protective effects of NAC on impaired spermatogenesis in SHR/cp could be due to the more pronounced state of oxidative stress observed in these rats compared with WKY.

  1. N-Acetyl-L-Cystein downregulates beta-amyloid precursor protein gene transcription in human neuroblastoma cells.

    Science.gov (United States)

    Studer, R; Baysang, G; Brack, C

    2001-01-01

    The causes for the sporadic form of Alzheimer's disease (AD) are still poorly understood, except from the fact that age is an important risk factor. The main component of the characteristic amyloid plaques in brains of AD patients are Abeta peptides, derivatives of the amyloid precursor protein APP. Oxidative stress may contribute to the aetiology of AD by dysregulation of APP metabolism. Overexpression of the APP gene could result in an increased secretion of neurotoxic Abeta peptides, while preventing the overexpression might be protective. We here report that the antioxidant N-Acetyl-L-Cystein (NAC) downregulates APP gene transcription in human neuroblastoma cells. The effect is reversible when cells are returned to NAC free medium. These results open up new possibilities for the development of therapeutic agents that intervene at the transcriptional level.

  2. Anti-tumor properties of orally administered glucosamine and N-acetyl-D-glucosamine oligomers in a mouse model.

    Science.gov (United States)

    Masuda, Sachie; Azuma, Kazuo; Kurozumi, Seiji; Kiyose, Masatoshi; Osaki, Tomohiro; Tsuka, Takeshi; Itoh, Norihiko; Imagawa, Tomohiro; Minami, Saburo; Sato, Kimihiko; Okamoto, Yoshiharu

    2014-10-13

    The current study evaluated the anti-tumor activities of N-acetyl-d-glucosamine oligomer (NACOS) and glucosamine oligomer (COS) after their oral administration in a tumor (colon 26)-bearing mouse model. Compared to the control group, NACOS and COS groups showed significantly suppressed tumor growth, and apparent, marked apoptosis in tumor tissues. Furthermore, serum interleukin-12p70 and interferon-γ levels significantly increased in the NACOS and COS groups compared to the corresponding levels in the control group. Collectively, the results indicate the oral administration of NACOS and COS could enhance innate immunity. Results of experiments in Myd-88 knockout mice revealed that the apparent effects were related to both Myd-88-dependent and Myd-88-independent pathways. The data indicated that oral administration of NACOS and COS produced anti-tumor effects through the induction of apoptosis and stimulation of the immune system, which suggests that NACOS and COS are candidate anti-tumor functional foods.

  3. UDP-N-Acetyl glucosamine pyrophosphorylase as novel target for controlling Aedes aegypti – molecular modeling, docking and simulation studies

    Directory of Open Access Journals (Sweden)

    Bhagath Kumar Palaka

    2014-12-01

    Full Text Available Aedes aegypti is a vector that transmits diseases like dengue fever, chikungunya, and yellow fever. It is distributed in all tropical and subtropical regions of the world. According to WHO reports, 40% of the world’s population is currently at risk for dengue fever. As vaccines are not available for such diseases, controlling mosquito population becomes necessary. Hence, this study aims at UDP-N-acetyl glucosamine pyrophosphorylase of Aedes aegypti (AaUAP, an essential enzyme for chitin metabolim in insects, as a drug target. Structure of AaUAP was predicted and validated using in-silico approach. Further, docking studies were performed using a set of 10 inhibitors out of which NAG9 was found to have good docking score, which was further supported by simulation studies. Hence, we propose that NAG9 can be considered as a potential hit in designing new inhibitors to control Aedes aegypti.

  4. Design, synthesis and evaluation of N-acetyl glucosamine (NAG)-PEG-doxorubicin targeted conjugates for anticancer delivery.

    Science.gov (United States)

    Pawar, Smita K; Badhwar, Archana J; Kharas, Firuza; Khandare, Jayant J; Vavia, Pradeep R

    2012-10-15

    Efficacy of anticancer drug is limited by the severe adverse effects induced by drug; therefore the crux is in designing delivery systems targeted only to cancer cells. Toward this objectives, we propose, synthesis of poly(ethylene glycol) (PEG)-doxorubicin (DOX) prodrug conjugates consisting N-acetyl glucosamine (NAG) as a targeting moiety. Multicomponent system proposed here is characterized by (1)H NMR, UV spectroscopy, and HPLC. The multicomponent system is evaluated for in vitro cellular kinetics and anticancer activity using MCF-7 and MDA-MB-231 cells. Molecular modeling study demonstrated sterically stabilized conformations of polymeric conjugates. Interestingly, PEG-DOX conjugate with NAG ligand showed significantly higher cytotoxicity compared to drug conjugate with DOX. In addition, the polymer drug conjugate with NAG and DOX showed enhanced internalization and retention effect in cancer cells, compared to free DOX. Thus, with enhanced internalization and targeting ability of PEG conjugate of NAG-DOX has implication in targeted anticancer therapy.

  5. The Antioxidant Role of Glutathione and N-Acetyl-Cysteine Supplements and Exercise-Induced Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Willoughby Darryn

    2005-12-01

    Full Text Available Abstract An increase in exercise intensity is one of the many ways in which oxidative stress and free radical production has been shown to increase inside our cells. Effective regulation of the cellular balance between oxidation and antioxidation is important when considering cellular function and DNA integrity as well as the signal transduction of gene expression. Many pathological states, such as cancer, Parkinson's disease, and Alzheimer's disease have been shown to be related to the redox state of cells. In an attempt to minimize the onset of oxidative stress, supplementation with various known antioxidants has been suggested. Glutathione and N-acetyl-cysteine (NAC are antioxidants which are quite popular for their ability to minimize oxidative stress and the downstream negative effects thought to be associated with oxidative stress. Glutathione is largely known to minimize the lipid peroxidation of cellular membranes and other such targets that is known to occur with oxidative stress. N-acetyl-cysteine is a by-product of glutathione and is popular due to its cysteine residues and the role it has on glutathione maintenance and metabolism. The process of oxidative stress is a complicated, inter-twined series of events which quite possibly is related to many other cellular processes. Exercise enthusiasts and researchers have become interested in recent years to identify any means to help minimize the detrimental effects of oxidative stress that are commonly associated with intense and unaccustomed exercise. It is possible that a decrease in the amount of oxidative stress a cell is exposed to could increase health and performance.

  6. Biosynthesis and turnover of O-acetyl and N-acetyl groups in the gangliosides of human melanoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Manzi, A.E.; Sjoberg, E.R.; Diaz, S.; Varki, A.

    1990-08-05

    We and others previously described the melanoma-associated oncofetal glycosphingolipid antigen 9-O-acetyl-GD3, a disialoganglioside O-acetylated at the 9-position of the outer sialic acid residue. We have now developed methods to examine the biosynthesis and turnover of disialogangliosides in cultured melanoma cells and in Golgi-enriched vesicles from these cells. O-Acetylation was selectively expressed on di- and trisialogangliosides, but not on monosialogangliosides, nor on glycoprotein-bound sialic acids. Double-labeling of cells with (3H)acetate and (14C)glucosamine introduced easily detectable labels into each of the components of the ganglioside molecules. Pulse-chase studies of such doubly labeled molecules indicated that the O-acetyl groups turn over faster than the parent molecule. When Golgi-enriched vesicles from these cells were incubated with (acetyl-3H)acetyl-coenzyme A, the major labeled products were disialogangliosides. (Acetyl-3H)O-acetyl groups were found at both the 7- and the 9-positions, indicating that both 7-O-acetyl GD3 and 9-O-acetyl GD3 were synthesized by the action of O-acetyltransferase(s) on endogenous GD3. Analysis of the metabolically labeled molecules confirmed the existence of both 7- and 9-O-acetylated GD3 in the intact cells. Surprisingly, the major 3H-labeled product of the in vitro labeling reaction was not O-acetyl-GD3, but GD3, with the label exclusively in the sialic acid residues. Fragmentation of the labeled sialic acids by enzymatic and chemical methods showed that the 3H-label was exclusively in (3H)N-acetyl groups. Analyses of the double-labeled sialic acids from intact cells also showed that the 3H-label from (3H)acetate was exclusively in the form of (3H)N-acetyl groups, whereas the 14C-label was at the 4-position.

  7. Glutathione transferases in bacteria.

    Science.gov (United States)

    Allocati, Nerino; Federici, Luca; Masulli, Michele; Di Ilio, Carmine

    2009-01-01

    Bacterial glutathione transferases (GSTs) are part of a superfamily of enzymes that play a key role in cellular detoxification. GSTs are widely distributed in prokaryotes and are grouped into several classes. Bacterial GSTs are implicated in a variety of distinct processes such as the biodegradation of xenobiotics, protection against chemical and oxidative stresses and antimicrobial drug resistance. In addition to their role in detoxification, bacterial GSTs are also involved in a variety of distinct metabolic processes such as the biotransformation of dichloromethane, the degradation of lignin and atrazine, and the reductive dechlorination of pentachlorophenol. This review article summarizes the current status of knowledge regarding the functional and structural properties of bacterial GSTs.

  8. The impact of fixatives on the binding of lectins to N-acetyl-glucosamine residues of human syncytiotrophoblast: a quantitative histochemical study

    DEFF Research Database (Denmark)

    Høyer, P E; Kirkeby, S

    1996-01-01

    binding to N-acetyl-galactosamine, mannose, galactose, and fucose was also significantly higher in sections from tissues fixed in an acid fixative compared with a neutral buffered fixative. Unfixed cryosections revealed a considerably lower degree of specific lectin binding compared with sections from...

  9. N-acetyl-meta-aminophenol, the alleged nontoxic isomer of acetaminophen, is toxic in both rat and human precision-cut liver slices

    NARCIS (Netherlands)

    Hadi, Mackenzie; Herpers, Bram; Dragovic, Sanja; van Swelm, Rachel P. L.; Russel, Frans G. M.; Commandeur, Jan N. M.; van de Water, Bob; Groothuis, Genoveva

    2012-01-01

    N-acetyl-meta-aminophenol (AMAP) is generally considered as a non-toxic regioisomer of the well-known hepatotoxicant acetaminophen (APAP). However, so far AMAP has only been shown to be non-toxic in mice and hamsters. To investigate whether AMAP could also be used as non-toxic analog of APAP in stud

  10. In vivo relaxation of N-acetyl-aspartate, creatine plus phosphocreatine, and choline containing compounds during the course of brain infarction: a proton MRS study

    DEFF Research Database (Denmark)

    Gideon, P; Henriksen, O

    1992-01-01

    the course of infarction can be explained by changes in T1 and T2 relaxation times, eight patients with acute stroke were studied. STEAM sequences with varying echo delay times and repetition times were used to measure T1 and T2 of N-acetyl-aspartate (NAA), creatine plus phosphocreatine (Cr+PCr) and choline...

  11. Lower "N"-Acetyl-Aspartate Levels in Prefrontal Cortices in Pediatric Bipolar Disorder: A (Superscript 1]H Magnetic Resonance Spectroscopy Study

    Science.gov (United States)

    Caetano, Sheila C.; Olvera, Rene L.; Hatch, John P.; Sanches, Marsal; Chen, Hua Hsuan; Nicoletti, Mark; Stanley, Jeffrey A.; Fonseca, Manoela; Hunter, Kristina; Lafer, Beny; Pliszka, Steven R.; Soares, Jair C.

    2011-01-01

    Objective: The few studies applying single-voxel [superscript 1]H spectroscopy in children and adolescents with bipolar disorder (BD) have reported low "N"-acetyl-aspartate (NAA) levels in the dorsolateral prefrontal cortex (DLPFC), and high myo-inositol/phosphocreatine plus creatine (PCr+Cr) ratios in the anterior cingulate. The aim of this study…

  12. Fluorescent sensor for selective determination of copper ion based on N-acetyl-L-cysteine capped CdHgSe quantum dots.

    Science.gov (United States)

    Wang, Qingqing; Yu, Xiangyang; Zhan, Guoqing; Li, Chunya

    2014-04-15

    Using N-acetyl-L-cysteine as a stabilizer, well water-dispersed, high-quality and stable CdHgSe quantum dots were facilely synthesized via a simple aqueous phase method. The as-prepared N-acetyl-L-cysteine capped CdHgSe quantum dots were thoroughly characterized by transmission electron microscopy, X-ray diffraction spectroscopy and FTIR. A fluorescent sensor for selective determination of copper ions was developed using N-acetyl-L-cysteine capped CdHgSe quantum dots as fluorescent probe. The fluorescence intensity of N-acetyl-L-cysteine capped CdHgSe quantum dots decreased when interacted with copper ions due to the formation of coordination complex and aggregates. The method possesses high selectivity and is not influenced by some potential interferences such as Ag(+), Zn(2+), Co(2+) and Ni(2+). Under the optimal conditions, the change of fluorescence intensity (ΔI) was linearly proportional to the concentration of copper ions in the range of 1.0×10(-9)-4.0×10(-7) mol L(-1), with a detection limit as low as 2.0×10(-10) mol L(-1) (S/N=3). The developed method had been successfully employed to determine Cu(2+) in shrimp and South-lake water samples, and the results were verified by atomic absorption spectroscopy. The fluorescent sensor was demonstrated to be selective, sensitive and simple for copper ion determination, and promise for practical applications.

  13. N-Acetyl-Cysteine as Effective and Safe Chelating Agent in Metal-on-Metal Hip-Implanted Patients: Two Cases

    Directory of Open Access Journals (Sweden)

    Andrea Giampreti

    2016-01-01

    Full Text Available Systemic toxicity associated with cobalt (Co and chromium (Cr containing metal hip alloy may result in neuropathy, cardiomyopathy, and hypothyroidism. However clinical management concerning chelating therapy is still debated in literature. Here are described two metal-on-metal hip-implanted patients in which N-acetyl-cysteine decreased elevated blood metal levels. A 67-year-old male who underwent Co/Cr hip implant in September 2009 referred to our Poison Control Centre for persisting elevated Co/Cr blood levels (from March 2012 to November 2014. After receiving oral high-dose N-acetyl-cysteine, Co/Cr blood concentrations dropped by 86% and 87% of the prechelation levels, respectively, and persisted at these latter concentrations during the following 6 months of follow-up. An 81-year-old female who underwent Co/Cr hip implant in January 2007 referred to our Centre for detection of high Co and Cr blood levels in June 2012. No hip revision was indicated. After a therapy with oral high-dose N-acetyl-cysteine Co/Cr blood concentrations decreased of 45% and 24% of the prechelation levels. Chelating agents reported in hip-implanted patients (EDTA, DMPS, and BAL are described in few cases. N-acetyl-cysteine may provide chelating sites for metals and in our cases reduced Co and Cr blood levels and resulted well tolerable.

  14. Lower "N"-Acetyl-Aspartate Levels in Prefrontal Cortices in Pediatric Bipolar Disorder: A (Superscript 1]H Magnetic Resonance Spectroscopy Study

    Science.gov (United States)

    Caetano, Sheila C.; Olvera, Rene L.; Hatch, John P.; Sanches, Marsal; Chen, Hua Hsuan; Nicoletti, Mark; Stanley, Jeffrey A.; Fonseca, Manoela; Hunter, Kristina; Lafer, Beny; Pliszka, Steven R.; Soares, Jair C.

    2011-01-01

    Objective: The few studies applying single-voxel [superscript 1]H spectroscopy in children and adolescents with bipolar disorder (BD) have reported low "N"-acetyl-aspartate (NAA) levels in the dorsolateral prefrontal cortex (DLPFC), and high myo-inositol/phosphocreatine plus creatine (PCr+Cr) ratios in the anterior cingulate. The aim of this study…

  15. A comparative study of MP2, B3LYP, RHF and SCC-DFTB force fields in predicting the vibrational spectra of N-acetyl-L-alanine-N'-methyl amide: VA and VCD spectra

    DEFF Research Database (Denmark)

    Bohr, Henrik; Jalkanen, Karl J.; Elstner, M.

    1999-01-01

    Recently we have looked for spectroscopic probes for secondary structural elements in the vibrational spectra of N-acetyl-L-alanine N'-methyl amide (NALANMA), L-alanine (LA), N-acetyl-L-alanyl-L-alanine N'-methyl amide (NALALANMA) and L-alanyl-L-alanine (LALA). Our goal has been to identify...

  16. Structural investigation of a novel N-acetyl glucosamine binding chi-lectin which reveals evolutionary relationship with class III chitinases.

    Science.gov (United States)

    Patil, Dipak N; Datta, Manali; Dev, Aditya; Dhindwal, Sonali; Singh, Nirpendra; Dasauni, Pushpanjali; Kundu, Suman; Sharma, Ashwani K; Tomar, Shailly; Kumar, Pravindra

    2013-01-01

    The glycosyl hydrolase 18 (GH18) family consists of active chitinases as well as chitinase like lectins/proteins (CLPs). The CLPs share significant sequence and structural similarities with active chitinases, however, do not display chitinase activity. Some of these proteins are reported to have specific functions and carbohydrate binding property. In the present study, we report a novel chitinase like lectin (TCLL) from Tamarindus indica. The crystal structures of native TCLL and its complex with N-acetyl glucosamine were determined. Similar to the other CLPs of the GH18 members, TCLL lacks chitinase activity due to mutations of key active site residues. Comparison of TCLL with chitinases and other chitin binding CLPs shows that TCLL has substitution of some chitin binding site residues and more open binding cleft due to major differences in the loop region. Interestingly, the biochemical studies suggest that TCLL is an N-acetyl glucosamine specific chi-lectin, which is further confirmed by the complex structure of TCLL with N-acetyl glucosamine complex. TCLL has two distinct N-acetyl glucosamine binding sites S1 and S2 that contain similar polar residues, although interaction pattern with N-acetyl glucosamine varies extensively among them. Moreover, TCLL structure depicts that how plants utilize existing structural scaffolds ingenuously to attain new functions. To date, this is the first structural investigation of a chi-lectin from plants that explore novel carbohydrate binding sites other than chitin binding groove observed in GH18 family members. Consequently, TCLL structure confers evidence for evolutionary link of lectins with chitinases.

  17. sup. alpha. N-acetyl derivatives of. beta. -endorphin-(1-31) and -(1-27) regulate the supraspinal antinociceptive activity of different opioids in mice

    Energy Technology Data Exchange (ETDEWEB)

    Garzon, J.; Sanchez-Blazquez, P. (Cajal Institute, Madrid (Spain))

    1991-01-01

    {sup {alpha}}N-acetyl human {beta}-endorphin(1-31) injected icv to mice antagonized the analgesic activity of {beta}-endorphin-(1-31) and morphine whereas the analgesia evoked by DADLE and DAGO was enhanced by this treatment. The modulatory activity of {sup {alpha}}N-acetyl {beta}-endorphin-(1-31) was exhibited at remarkable low doses (fmols) reaching a maximum that persisted even though the dose was increased 100,000 times. The regulatory effect of a single dose of the acetylated neuropeptide lasted for 24h. The activity of {sup {alpha}}N-acetyl human {beta}-endorphin(1-31) was partially retained by the shorter peptide {sup {alpha}}N-acetyl human {beta}-endorphin-(1-27) and to a lesser extent by {beta}-endorphin-(1-27), {beta}-endorphin-(1-31) lacked this regulatory activity on opioid analgesia. Acetylated {beta}-endorphin-(1-31) displayed a biphasic curve when competing with 5 pM ({sup 125}I)-Tyr{sup 27} human {beta}-endorphin-(1-31) specific binding, the first step was abolished with an apparent IC{sub 50} of 0.35 nM, and the rest with an IC{sub 50} of 200 nM. It is suggested that {sup {alpha}}N-acetyl {beta}-endorphin-(1-31) changed the efficiency of the opioid analgesics by acting upon a specific substrate that is functionally coupled to the opioid receptor, presumably the guanine nucleotide binding regulatory proteins G{sub i}/G{sub 0}.

  18. Mammalian cytosolic glutathione transferases.

    Science.gov (United States)

    Dourado, Daniel F A R; Fernandes, Pedro Alexandrino; Ramos, Maria João

    2008-08-01

    Glutathione Transferases (GSTs) are crucial enzymes in the cell detoxification process catalyzing the nucleophilic attack of glutathione (GSH) on toxic electrophilic substrates and producing a less dangerous compound. GSTs studies are of great importance since they have been implicated in the development of drug resistance in tumoral cells and are related to human diseases such as Parkinson's, Alzheimer's, atherosclerois, liver cirrhosis, aging and cataract formation. In this review we start by providing an evolutionary perspective of the mammalian cytosolic GSTs known to date. Later on we focus on the more abundant classes alpha, mu and pi and their structure, catalysis, metabolic associated functions, drug resistance relation and inhibition methods. Finally, we introduce the recent insights on the GST class zeta from a metabolic perspective.

  19. The lectin domain of UDP-N-acetyl-D-galactosamine: polypeptide N-acetylgalactosaminyltransferase-T4 directs its glycopeptide specificities

    DEFF Research Database (Denmark)

    Hassan, H; Reis, C A; Bennett, E P;

    2000-01-01

    The initiation step of mucin-type O-glycosylation is controlled by a large family of homologous UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (GalNAc-transferases). Differences in kinetic properties, substrate specificities, and expression patterns of these isoenzymes provide for diff...

  20. The ratio of N-acetyl aspartate to glutamate correlates with disease duration of amyotrophic lateral sclerosis.

    Science.gov (United States)

    Sako, Wataru; Abe, Takashi; Izumi, Yuishin; Harada, Masafumi; Kaji, Ryuji

    2016-05-01

    Glutamate (Glu)-induced excitotoxicity has been implicated in the neuronal loss of amyotrophic lateral sclerosis. To test the hypothesis that Glu in the primary motor cortex contributes to disease severity and/or duration, the Glu level was investigated using MR spectroscopy. Seventeen patients with amyotrophic lateral sclerosis were diagnosed according to the El Escorial criteria for suspected, possible, probable or definite amyotrophic lateral sclerosis, and enrolled in this cross-sectional study. We measured metabolite concentrations, including N-acetyl aspartate (NAA), creatine, choline, inositol, Glu and glutamine, and performed partial correlation between each metabolite concentration or NAA/Glu ratio and disease severity or duration using age as a covariate. Considering our hypothesis that Glu is associated with neuronal cell death in amyotrophic lateral sclerosis, we investigated the ratio of NAA to Glu, and found a significant correlation between NAA/Glu and disease duration (r=-0.574, p=0.02). The "suspected" amyotrophic lateral sclerosis patients showed the same tendency as possible, probable and definite amyotrophic lateral sclerosis patients in regard to correlation of NAA/Glu ratio with disease duration. The other metabolites showed no significant correlation. Our findings suggested that glutamatergic neurons are less vulnerable compared to other neurons and this may be because inhibitory receptors are mainly located presynaptically, which supports the notion of Glu-induced excitotoxicity.

  1. Dextromethorphan and caffeine as probes for simultaneous determination of debrisoquin-oxidation and N-acetylation phenotypes in children.

    Science.gov (United States)

    Evans, W E; Relling, M V; Petros, W P; Meyer, W H; Mirro, J; Crom, W R

    1989-05-01

    The feasibility and reliability of simultaneously determining debrisoquin oxidation and N-acetylation phenotypes was assessed in children with use of two innocuous substrate probes given by mouth, 30 mg dextromethorphan (Pertussin ES) and 25 to 46 mg caffeine (Coca-Cola beverage). Twenty-six children and adolescents (aged 3 to 21 years) were studied three times, once with each substrate given alone and once with the two substrates given together. Urine was collected for 4 hours, and the molar urinary metabolic ratios for dextromethorphan:dextrorphan and for two caffeine metabolites (AFMU:1X) were determined by HPLC ultraviolet assays. The urinary metabolic ratios for both substrates were not significantly different when the substrates were given alone compared with when they were given together. There also was no difference in either the oxidation or acetylation phenotype assignments when the two substrates were given alone and when they were given together. No adverse effects were observed. We conclude that dextromethorphan and caffeine can be given together to simultaneously determine oxidation and acetylation phenotypes and can thereby provide an innocuous, noninvasive method for the assessment of polymorphic drug metabolism in various pediatric populations.

  2. Chronic treatment with N-acetyl-cystein delays cellular senescence in endothelial cells isolated from a subgroup of atherosclerotic patients.

    Science.gov (United States)

    Voghel, Guillaume; Thorin-Trescases, Nathalie; Farhat, Nada; Mamarbachi, Aida M; Villeneuve, Louis; Fortier, Annik; Perrault, Louis P; Carrier, Michel; Thorin, Eric

    2008-05-01

    Endothelial senescence may contribute to the pathogenesis of age-related vascular disorders. Furthermore, chronic exposure to risk factors for cardiovascular disease (CVD) accelerates the effects of chronological aging by generating stress-dependent damages, including oxidative stress, therefore promoting stress-induced premature senescence. Our objective was to determine whether a chronic treatment with an antioxidant (N-acetyl-cystein, NAC) could delay senescence of endothelial cells (EC) isolated and cultured from arterial segments of patients with severe coronary artery disease. If EC were considered as one population (n=26), chronic NAC treatment slightly shortened telomere attrition rate associated with senescence but did not significantly delay the onset of endothelial senescence. However, in a subgroup of NAC-treated EC (n=15) cellular senescence was significantly delayed, NAC decreased lipid peroxidation (HNE), activated the catalytic subunit of telomerase (hTERT) and inhibited telomere attrition. In contrast, in another subgroup of EC (n=11) characterized by initial short telomeres, no effect of NAC on HNE and high levels of DNA damages, the antioxidant was not beneficial on senescence, suggesting an irreversible stress-dependent damage. In conclusion, chronic exposure to NAC can delay senescence of diseased EC via hTERT activation and transient telomere stabilization, unless oxidative stress-associated cell damage has become irreversible.

  3. Evaluation of N-Acetyl Cysteine performance in acetaminophen poisoning using certain liver and renal factors in plasma

    Directory of Open Access Journals (Sweden)

    Armin Salek Maghsoudi

    2014-10-01

    Full Text Available Background: Annually, acetaminophen poisoning causes probable acute liver and renal failures in different societies. N-acetyl cystein (NAC, first suggested as an effective antidote to fight against acetaminophen poisoning in 1970, prevents the binding of NAPQI to hepatic cells. Methods: In the present study 30 patients with the average age of 27 and acetaminophen poisoning who referred to the poisons unit of Sina hospital in Tabriz were selected as the study sample. During the 24 hours of hospitalization, the blood samples of the patients were taken and collected in heparinized tubes. The plasma was separated by centrifuge and kept in tubes in -70°C until it was analyzed by a high performance liquid chromatography method (HPLC and laboratory analytical kits. Results: the glutathione peroxidase (GPX activity difference between the patients and control group was significant at first (P0.05. Conclusion: The activity level of GPX changed before a tangible change in regular liver enzymes. Urea level increased after 24 hours of treatment despite serum therapy and hydration condition.

  4. Production of N-acetyl-beta-D-glucosamine from chitin by Aeromonas sp. GJ-18 crude enzyme.

    Science.gov (United States)

    Kuk, J H; Jung, W J; Jo, G H; Kim, Y C; Kim, K Y; Park, R D

    2005-08-01

    A bacterium, GJ-18, having strong chitinolytic activity was isolated from coastal soil. The isolated strain was identified as Aeromonas sp. by morphological and biochemical properties along with 16S rRNA gene sequence. The crude chitinolytic activity of culture supernatants was maximal on the 5th day of culture. Below 45 degrees C, chitin was effectively hydrolyzed to N-acetyl-beta-D-glucosamine (GlcNAc) by Aeromonas sp. GJ-18 crude enzymes, but hydrolysis decreased markedly above 50 degrees C. The optimum pH for enzyme activity was 5.0. TLC and HPLC analysis revealed that, below 45 degrees C, the major reaction product was GlcNAc with a small amount of (GlcNAc)(2) and (GlcNAc)(3), whereas above 50 degrees C the major product was (GlcNAc)(2). When swollen chitin (100 mg) was incubated with crude enzyme preparations (10 U) at 40 degrees C, chitin was hydrolyzed to 83.0 and 94.9% yield of GlcNAc within 5 and 9 days, respectively.

  5. Effects of N-acetyl-L-cysteine on bleomycin induced oxidative stress in malignant testicular germ cell tumors.

    Science.gov (United States)

    Cort, Aysegul; Ozdemir, Evrim; Timur, Mujgan; Ozben, Tomris

    2012-12-01

    Testicular cancer is a very common cancer in males aged 15-44 years. Bleomycin is used in chemotherapy regimens in the treatment of patients having testicular germ-cell tumor. Bleomycin generates oxygen radicals, induces oxidative cleavage of DNA strand and induces apoptosis in cancer cells. There is no study in the literature investigating effects of N-Acetyl-L-Cysteine (NAC) on bleomycin-induced oxidative stress in testicular germ cell tumors. For this reason, we studied effects of NAC on oxidative stress produced in wild-type NTera-2 and p53-mutant NCCIT testis cancer cells incubated with bleomycin and compared the results with H(2)O(2) which directly produces oxidative stress. We determined protein carbonyl content, thiobarbituric acid reactive substances (TBARS), glutathione (GSH), 8-isoprostane, lipid hydroperoxide levels and total antioxidant capacity in both testicular cancer cells. Bleomycin and H(2)O(2) significantly increased 8-isoprostane, TBARS, protein carbonyl and lipid hydroperoxide levels in NTera-2 and NCCIT cells. Bleomycin and H(2)O(2) significantly decreased antioxidant capacity and GSH levels in both cell lines. Co-incubation with NAC significantly decreased lipid hydroperoxide, 8-isoprostane, protein carbonyl content and TBARS levels increased by bleomycin and H(2)O(2). NAC enhanced GSH levels and antioxidant capacity in the NTera-2 and NCCIT cells. It can be concluded that NAC diminishes oxidative stress in human testicular cancer cells induced by bleomycin and H(2)O(2).

  6. Mild to severe lithium-induced nephropathy models and urine N-acetyl-beta-D-glucosaminidase in rats.

    Science.gov (United States)

    Ida, S; Yokota, M; Ueoka, M; Kiyoi, K; Takiguchi, Y

    2001-10-01

    Long-term treatment with lithium induces functional and/or structural disturbances in the kidneys. However, no procedure has been established for the early diagnosis of lithium intoxication. In this study, we prepared mild to severe lithium-induced nephropathy rat models and examined the usefulness of urine N-acetyl-beta-D-glucosaminidase (NAG) for the early diagnosis of lithium-induced renal insufficiency. Lithium was administered by repeated intraperitoneal injection (1, 2 and 4 mEq/kg/day for 10 days). We also measured the plasma creatinine and paraaminohippuric acid (PAH) clearance, and observed renal histological changes. Lithium pretreatment elevated the plasma creatinine level and decreased PAH clearance in a dose-dependent manner. The NAG level in the lithium 4 mEq/kg group was very high. The levels in the lithium 1 mEq/kg and 2 mEq/kg groups were almost the same and were higher than the control group. A histological examination of the kidney revealed glomerular congestion and/or atrophy and tubular expansion in all of the groups except the control group. These histological changes were dose-dependent. In conclusion, urine NAG may be useful in the early diagnosis of renal side effects caused by lithium therapy. When the urine NAG level becomes high in a patient taking lithium for bipolar disorder, the physician may need to consider lithium-induced renal insufficiency.

  7. Activity of N-acetyl-β-D-hexosaminidase in the saliva of children with type 1 diabetes

    Directory of Open Access Journals (Sweden)

    Beata Zalewska-Szajda

    2013-09-01

    Full Text Available Background/Aim: Type 1 diabetes is one of the most common chronic diseases in children. The aim of the study was to evaluate the catabolism of glycoconjugates in saliva of children with type 1 diabetes, by measurement of the activity of N-acetyl-β-D-hexosaminidase (HEX in their saliva.Material/Methods: The study was performed in 65 children with type 1 diabetes and 39 healthy children. Salivary HEX activity was determined spectrophotometrically by the method of Zwierz et al. in the modification of Marciniak et al. Protein was determined by the bicinchoninic acid method (BCATM Assay Protein Kit. Concentration of the HEX activity was expressed in pKat/mL and HEX specific activity in pKat/μg of protein.Results: A significant increase in the concentration and the specific activity of HEX in the saliva of children with type 1 diabetes, compared to healthy children, was found.Conclusions: Type 1 diabetes increases salivary catabolism of glycoconjugates reflected by the significant increase in the activity of HEX in the saliva of children with type 1 diabetes compared to healthy children. The salivary HEX activity may be used in the diagnosis of children with type 1 diabetes after confirmation of our results on a larger cohort of children with type 1 diabetes.

  8. [Isoforms A and B of lysosomal N-acetyl-beta-D-hexosaminidase in serum and urine of parenterally fed patients].

    Science.gov (United States)

    Raczkowska, Katarzyna; Zalewska-Szajda, Beata; Chojnowska, Sylwia; Kepka, Alina; Raczkowski, Krzysztof; Waszkiewicz, Napoleon; Siedlecka-Czykier, Edyta; Dadan, Jacek; Snarska, Jadwiga; Zwierz, Krzysztof; Ładny, Jerzy Robert; Szajda, Sławomir Dariusz

    2013-05-01

    Parenteral nutrition entails numerous metabolic complications resulting from food bypass of the gastrointestinal tract. Up to now have not been established all complications of parenteral nutrition, despite intensive research and clinical observations. Knowledge of the biochemical changes resulting from parenteral nutrition is essential to effective prevention, early detection and effective treatment of the metabolic disorders induced by parenteral nutrition. The aim of the study was to evaluate the catabolism of glycoconjugates of parenterally fed patients, reflected by the activity of N-acetyl-beta-D-hexosaminidase (HEX): HEX A and HEX B isoenzymes in serum and urine. Samples of blood and urine were collected from 23 patients: before intravenous alimentation, at start, as well as of fifth and tenth day of parenteral nutrition. The activity of HEX A and HEX B in serum and urine was determined by the colorimetric method of Zwierz et al. as modified by Marciniak et al. The activity of urinary HEXA and HEX B has been calculated per 1 mg of creatinine. The activity of serum HEXA significantly decreased at fifth day, in comparison to the activity before parenteral alimentation, and significantly increased at tenth day of parenteral nutrition. The activity of HEX B in serum increased significantly at fifth and tenth day of the parenteral nutrition. Parenteral nutrition alter the catabolism of glycoconjugates, reflected by significant changes in serum HEX A and HEX B activities. Urine was the not appropriate material to evaluate the catabolism of glycoconjugates in view of HEX A and HEX B activities.

  9. Permanent and transient effects of locally delivered n-acetyl cysteine in a guinea pig model of cochlear implantation.

    Science.gov (United States)

    Eastwood, Hayden; Pinder, Darren; James, David; Chang, Andrew; Galloway, Stuart; Richardson, Rachael; O'Leary, Stephen

    2010-01-01

    Protection of residual hearing after cochlear implant surgery can improve the speech and music perception of cochlear implant recipients, particularly in the presence of background noise. Surgical trauma and chronic inflammation are thought to be responsible for a significant proportion of residual hearing loss after surgery. Local delivery of the anti-oxidant precursor n-acetyl cysteine (NAC) to the cochlea via round window 30min prior to surgery, increased the level of residual hearing at 24-32kHz 4weeks post surgery compared to controls. The hearing protection was found in the basal turn near the site of implantation. Coincidentally, the basal turn was also the location that sustained the greatest hearing loss. As well as protecting residual hearing, NAC-treated animals demonstrated a reduction in the chronic inflammatory changes associated with implantation. While these findings indicate that anti-oxidant therapy can be used to reduce the hearing loss associated with surgical trauma, the local delivery of NAC was associated with a transient increase in hearing thresholds, and osseoneogenesis was seen in a greater number of NAC-treated animals. These side-effects would limit its clinical use through local cochlear administration. However, it is not known yet whether these effects would also be produced by other anti-oxidants, or ameliorated by using a different route of administration.

  10. N-acetyl-L-cysteine affects growth, extracellular polysaccharide production, and bacterial biofilm formation on solid surfaces.

    Science.gov (United States)

    Olofsson, Ann-Cathrin; Hermansson, Malte; Elwing, Hans

    2003-08-01

    N-Acetyl-L-cysteine (NAC) is used in medical treatment of patients with chronic bronchitis. The positive effects of NAC treatment have primarily been attributed to the mucus-dissolving properties of NAC, as well as its ability to decrease biofilm formation, which reduces bacterial infections. Our results suggest that NAC also may be an interesting candidate for use as an agent to reduce and prevent biofilm formation on stainless steel surfaces in environments typical of paper mill plants. Using 10 different bacterial strains isolated from a paper mill, we found that the mode of action of NAC is chemical, as well as biological, in the case of bacterial adhesion to stainless steel surfaces. The initial adhesion of bacteria is dependent on the wettability of the substratum. NAC was shown to bind to stainless steel, increasing the wettability of the surface. Moreover, NAC decreased bacterial adhesion and even detached bacteria that were adhering to stainless steel surfaces. Growth of various bacteria, as monocultures or in a multispecies community, was inhibited at different concentrations of NAC. We also found that there was no detectable degradation of extracellular polysaccharides (EPS) by NAC, indicating that NAC reduced the production of EPS, in most bacteria tested, even at concentrations at which growth was not affected. Altogether, the presence of NAC changes the texture of the biofilm formed and makes NAC an interesting candidate for use as a general inhibitor of formation of bacterial biofilms on stainless steel surfaces.

  11. Aqueous based synthesis of N-acetyl-L-cysteine capped ZnSe nanocrystals with intense blue emission

    Science.gov (United States)

    Soheyli, Ehsan; Sahraei, Reza; Nabiyouni, Gholamreza

    2016-10-01

    In this work a very simple reflux route for preparation of ZnSe nanocrystals with minor modification and faster preparation over conventional ones is introduced. X-ray diffraction analysis indicated that the ZnSe nanocrystals have a cubic structure. The complete disappearance of the S-H band in FT-IR spectrum of N-acetyl-L-cysteine capped ZnSe nanocrystals was an indication over formation of Zn-thiol covalent bonds at the surface of the nanocrystals which results in passivation of small nanocrystals. The strong size-quantization regime was responsible of significant blue shift in absorption/emission spectra. Using the well-known calculations, band gap and Urbach energy of the ZnSe nanocrystals were measured and their average size was estimated optically to be around 4.6 nm along with the TEM image. A dark blue emission with higher relative intensity of excitonic to trap emissions (compared to conventional method), very narrow excitonic emission peak of about 16 nm and remarkable stability was obtained from the ZnSe nanocrystals.

  12. Facile synthesis of N-acetyl-L-cysteine capped CdHgSe quantum dots and selective determination of hemoglobin.

    Science.gov (United States)

    Wang, Qingqing; Zhan, Guoqing; Li, Chunya

    2014-01-03

    Using N-acetyl-L-cysteine (NAC) as a stabilizer, well water-dispersed, high-quality and stable CdHgSe quantum dots were facilely synthesized via a simple aqueous phase method. The as-prepared NAC capped CdHgSe quantum dots were thoroughly characterized by fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy and transmission electron microscopy. A novel method for the selective determination of hemoglobin (Hb) was developed based on fluorescence quenching of the NAC capped CdHgSe quantum dots. A number of key factors including pH value of phosphate buffer solution, quantum dots concentration, the adding sequence of reagents and reaction time that influence the analytical performance of the NAC capped CdHgSe quantum dots in Hb determination were investigated. Under the optimal experimental conditions, the change of fluorescence intensity (ΔI) was linearly proportional to the concentration of Hb in the range of 4.0×10(-9)-4.4×10(-7) mol L(-1) with a detection limit of 2.0×10(-9) mol L(-1). The developed method has been successfully employed to determine Hb in human urine samples.

  13. Protein oxidation under extremely low frequency electric field in guinea pigs. Effect of N-acetyl-L-cysteine treatment.

    Science.gov (United States)

    Güler, Göknur; Türközer, Zerrin; Ozgur, Elcin; Tomruk, Arin; Seyhan, Nesrin; Karasu, Cimen

    2009-03-01

    Modern age exposes humans to an increasing level of electromagnetic activity in their environment due to overhead power lines and transformers around residential areas. Studies have shown that treatment with antioxidants can suppress the oxidative damage induced by electromagnetic fields in various frequencies of the non-ionizing radiation band. In this study, we detected protein carbonyl content (PCO), advanced oxidation protein products (AOPP) in liver and 3-nitrotyrosine (3-NT) levels in plasma of guinea pigs in order to investigate the effects of N-acetyl-L-cysteine (NAC) administration on oxidative protein damage induced by power frequency electric (E) field (50 Hz, 12 kV/m, 7 days/8 h/day). We also analyzed hepatic hydroxyproline level to study protein synthesis. According to the findings of the present study, no statistically significant changes occurred in PCO, AOPP and 3-NT levels of the guinea pigs that were exposed to the E field with respect to the control group. However, liver hydroxyproline level was significantly diminished in the E field exposure group compared to the control and PCO, hydroxyproline and 3-NT levels changed significantly in the NAC-administrated groups.

  14. Spectroscopic investigations on the effect of N-Acetyl-L-cysteine-Capped CdTe Quantum Dots on catalase

    Science.gov (United States)

    Sun, Haoyu; Yang, Bingjun; Cui, Erqian; Liu, Rutao

    2014-11-01

    Quantum dots (QDs) are recognized as some of the most promising semiconductor nanocrystals in biomedical applications. However, the potential toxicity of QDs has aroused wide public concern. Catalase (CAT) is a common enzyme in animal and plant tissues. For the potential application of QDs in vivo, it is important to investigate the interaction of QDs with CAT. In this work, the effect of N-Acetyl-L-cysteine-Capped CdTe Quantum Dots with fluorescence emission peak at 612 nm (QDs-612) on CAT was investigated by fluorescence, synchronous fluorescence, fluorescence lifetime, ultraviolet-visible (UV-vis) absorption and circular dichroism (CD) techniques. Binding of QDs-612 to CAT caused static quenching of the fluorescence, the change of the secondary structure of CAT and the alteration of the microenvironment of tryptophan residues. The association constants K were determined to be K288K = 7.98 × 105 L mol-1 and K298K = 7.21 × 105 L mol-1. The interaction between QDs-612 and CAT was spontaneous with 1:1 stoichiometry approximately. The CAT activity was also inhibited for the bound QDs-612. This work provides direct evidence about enzyme toxicity of QDs-612 to CAT in vitro and establishes a new strategy to investigate the interaction between enzyme and QDs at a molecular level, which is helpful for clarifying the bioactivities of QDs in vivo.

  15. Effects of N-acetyl-L-cysteine on the membrane vesicle release and growth of respiratory pathogens.

    Science.gov (United States)

    Volgers, Charlotte; Benedikter, Birke J; Grauls, Gert E; Hellebrand, Pauline H M; Savelkoul, Paul H M; Stassen, Frank R M

    2017-05-01

    Bacterial infections contribute to the disease progression of chronic obstructive pulmonary disease by stimulating mucus production in the airways. This increased mucus production and other symptoms are often alleviated when patients are treated with mucolytics such as N-acetyl-L-cysteine (NAC). Moreover, NAC has been suggested to inhibit bacterial growth. Bacteria can release membrane vesicles (MVs) in response to stress, and recent studies report a role for these proinflammatory MVs in the pathogenesis of airways disease. Yet, until now it is not clear whether NAC also affects the release of these MVs. This study set out to determine whether NAC, at concentrations reached during high-dose nebulization, affects bacterial growth and MV release of the respiratory pathogens non-typeable Haemophilus influenzae (NTHi), Moraxella catarrhalis (Mrc), Streptococcus pneumoniae (Spn) and Pseudomonas aeruginosa (Psa). We observed that NAC exerted a strong bacteriostatic effect, but also induced the release of proinflammatory MVs by NTHi, Mrc and Psa, but not by Spn. Interestingly, NAC also markedly blunted the release of TNF-α by naive macrophages in response to MVs. This suggests that the application of NAC by nebulization at a high dosage may be beneficial for patients with airway conditions associated with bacterial infections. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Spectrophotometric Determination of N-Acetyl-L-Cysteine and N-(2-Mercaptopropionyl-Glycine in Pharmaceutical Preparations

    Directory of Open Access Journals (Sweden)

    Lea Kukoc-Modun

    2011-01-01

    Full Text Available A simple spectrophotometric method for the determination of N-acetyl-L-cysteine (NAC and N-(2-mercaptopropionylglycine (MPG in pharmaceutical preparations was developed, validated, and used. The proposed equilibrium method is based on a coupled two-step redox and complexation reaction. In the first step, Fe(III is reduced to Fe(II by NAC or MPG. Subsequently, Fe(II is complexed with 2,4,6-tripyridyl-s-triazine (TPTZ. Several analytical parameters of the method were optimized for NAC and MPG analysis in the concentration range from 1.0 μM to 100.0 μM. Regression analysis of the calibration data showed a good correlation coefficient (0.9999. The detection limit of the method was 0.14 μM for NAC and 0.13 μM for MPG. The method was successfully applied to quantify NAC and MPG in pharmaceutical preparations. No interferences were observed from common pharmaceutical excipients.

  17. Cortical N-acetyl aspartate is a predictor of long-term clinical disability in multiple sclerosis.

    Science.gov (United States)

    Wu, Xingchen; Hanson, Lars Grüner; Skimminge, Arnold; Sorensen, Per Soelberg; Paulson, Olaf Bjarne; Mathiesen, Henrik Kahr; Blinkenberg, Morten

    2014-08-01

    To evaluate the prognostic value of the cortical N-acetyl aspartate to creatine ratio (NAA/Cr) in early relapsing-remitting multiple sclerosis (RRMS). Sixteen patients with newly diagnosed RRMS were studied by serial MRI and MR spectroscopic imaging (MRSI) once every 6 months for 24 months. Clinical examinations, including the expanded disability status scale (EDSS), were performed at baseline, month 24, and at year 7. Baseline cortical NAA/Cr correlated inversely with EDSS at month 24 (r  =  -0·61, P EDSS ≧ 4 had a lower baseline cortical NAA/Cr compared to those with EDSS less than 4 (P EDSS at the 7-year follow-up (r  =  -0·56, P EDSS ≧ 4 had a lower baseline cortical NAA/Cr compared to those with EDSS less than 4 (P EDSS at month 24 (r  =  -0·61, P EDSS at year 7. Cortical NAA/Cr in early RRMS correlated with clinical disability after 2 and 7 years and may be used as a predictor of long-term disease outcome.

  18. Reaction pathway and free energy profile for papain-catalyzed hydrolysis of N-acetyl-Phe-Gly 4-nitroanilide.

    Science.gov (United States)

    Wei, Donghui; Huang, Xiaoqin; Liu, Junjun; Tang, Mingsheng; Zhan, Chang-Guo

    2013-07-30

    Possible reaction pathways for papain-catalyzed hydrolysis of N-acetyl-Phe-Gly 4-nitroanilide (APGNA) have been studied by performing pseudobond first-principles quantum mechanical/molecular mechanical-free energy (QM/MM-FE) calculations. The whole hydrolysis process includes two stages: acylation and deacylation. For the acylation stage of the catalytic reaction, we have explored three possible paths (A, B, and C) and the corresponding free energy profiles along the reaction coordinates. It has been demonstrated that the most favorable reaction path in this stage is path B consisting of two reaction steps: the first step is a proton transfer to form a zwitterionic form (i.e., Cys-S⁻/His-H⁺ ion-pair), and the second step is the nucleophilic attack on the carboxyl carbon of the substrate accompanied by the dissociation of 4-nitroanilide. The deacylation stage includes the nucleophilic attack of a water molecule on the carboxyl carbon of the substrate and dissociation between the carboxyl carbon of the substrate and the sulfhydryl sulfur of Cys25 side chain. The free energy barriers calculated for the acylation and deacylation stages are 20.0 and 10.7 kcal/mol, respectively. Thus, the acylation is rate-limiting. The overall free energy barrier calculated for papain-catalyzed hydrolysis of APGNA is 20.0 kcal/mol, which is reasonably close to the experimentally derived activation free energy of 17.9 kcal/mol.

  19. Inhibition of sulfur mustard-increased protease activity by niacinamide, N-acetyl-L-cysteine or dexamethasone

    Energy Technology Data Exchange (ETDEWEB)

    Cowan, F.M.; Broomfield, C.A.; Smith, W.J.

    1991-03-11

    The pathologic mechanism of sulfur mustard-induced skin vesication is as yet undefined. Papirmeister et al. have postulated a biochemical mechanism for sulfur mustard-induced cutaneous injury involving sequelae of DNA alkylation, metabolic disruption resulting in NAD+ depletion and activation of protease. The authors have utilized a chromogenic peptide substrate assay to establish that human peripheral blood lymphocytes exposed 24 hr previously to sulfur mustard exhibited an increase in proteolytic activity. Doses of compounds known to alter the biochemical events associated with sulfur mustard exposure or reduce protease activity were tested in this system for their ability to block the sulfur mustard-induced protease activity. Treatment with niacinamide 1 hr after or with N-acetyl-L-cysteine or dexamethasone 24 hr prior to sulfur mustard exposure resulted in a decrease of 39%, 33% and 42% respectively of sulfur mustard-increased protease activity. These data suggest that therapeutic intervention into the biochemical pathways that culminate in protease activation might serve as an approach to treatment of sulfur mustard-induced pathology.

  20. N-acetyl-cysteine inhibits liver oxidative stress markers in BALB/c mice infected with Leishmania amazonensis

    Science.gov (United States)

    Gasparotto, Juciano; Kunzler, Alice; Senger, Mario Roberto; de Souza, Celeste da Silva Freitas; de Simone, Salvatore Giovanni; Bortolin, Rafael Calixto; Somensi, Nauana; Dal-Pizzol, Felipe; Moreira, José Claudio Fonseca; Abreu-Silva, Ana Lúcia; Calabrese, Kátia da Silva; Silva, Floriano Paes; Gelain, Daniel Pens

    2017-01-01

    BACKGROUND Leishmaniasis is a parasitosis caused by several species of the genus Leishmania. These parasites present high resistance against oxidative stress generated by inflammatory cells. OBJECTIVES To investigate oxidative stress and molecular inflammatory markers in BALB/c mice infected with L. amazonensis and the effect of antioxidant treatment on these parameters. METHODS Four months after infection, oxidative and inflammatory parameters of liver, kidneys, spleen, heart and lungs from BALB/c mice were assessed. FINDINGS In liver, L. amazonensis caused thiol oxidation and nitrotyrosine formation; SOD activity and SOD2 protein content were increased while SOD1 protein content decreased. The content of the cytokines IL-1β, IL-6, TNF-α, and the receptor of advanced glycation endproducts (RAGE) increased in liver. Treatment with the antioxidant N-acetyl-cysteine (20 mg/kg b.w) for five days inhibited oxidative stress parameters. MAIN CONCLUSIONS L. amazonensis induces significant alterations in the redox status of liver but not in other organs. Acute antioxidant treatment alleviates oxidative stress in liver, but it had no effect on pro-inflammatory markers. These results indicate that the pathobiology of leishmaniasis is not restricted to the cutaneous manifestations and open perspectives for the development of new therapeutic approaches to the disease, especially for liver function. PMID:28177049

  1. Expression of Genes Related to Oxidative Stress in Yeast Treated with Ionizing Radiation and N-acetyl -L-cysteine

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ji Young; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Nili, Mohammad [Dawnesh Radiation Research Institute, Barcelona (Spain)

    2010-10-15

    Ionizing radiation (IR) induces water radiolysis, which generates highly reactive hydroxyl radicals. Reactive oxygen species (ROS) cause apoptosis and cell damage including DNA strand breaks (DSBs), base damage, protein damage and lipid-hydroperoxide. Detoxifying enzymes are immediately triggered for ROS scavenging. Yeast contains two forms of superoxide dismutase (SOD). SOD1 as a cytosolic copper-zinc superoxide dismutase is located in the cytoplasm and cytosol. SOD2 as a manganese containing enzyme is act in mitochondria matrix and mitochondrion. These enzymes scavenge superoxide radicals by catalyzing the conversion of two of these radicals into hydrogen peroxide and molecular oxygen. The hydrogen peroxide formed by superoxide dismutase and by other processes is scavenged by catalase, a ubiquitous heme protein that catalyzes the dismutation of hydrogen peroxide into water and molecular oxygen. Yeast contains two catalases. Catalase A (CTA1) and Cytosolic catalase T (CTT1) is located in peroxisome and cytoplasm, respectively. Yeast has two glutathione (GSH) peroxidases, which are GPX1 and GPX2. GPX1 and GPX2 are component of cellular component and cytoplasm, respectively. The biochemical function of GSH peroxidase is to reduce lipid-hydroperoxides to their corresponding alcohols and to reduce free hydrogen peroxide to water. Otherwise, chemicals and materials help ROS detoxification against oxidative damage. N-acetyl-Lcysteine (NAC) having a thiol, a precursor for glutathione (GSH), is known as one of the antioxidants. In this study, we examined the effect of NAC through gene expressions related to protective enzyme against oxidative stress in yeast

  2. Identification of the enzyme responsible for N-acetylation of norfloxacin by Microbacterium sp. Strain 4N2-2.

    Science.gov (United States)

    Kim, Dae-Wi; Feng, Jinhui; Chen, Huizhong; Kweon, Ohgew; Gao, Yuan; Yu, Li-Rong; Burrowes, Vanessa J; Sutherland, John B

    2013-01-01

    Microbacterium sp. 4N2-2, isolated from a wastewater treatment plant, converts the antibacterial fluoroquinolone norfloxacin to N-acetylnorfloxacin and three other metabolites. Because N-acetylation results in loss of antibacterial activity, identification of the enzyme responsible is important for understanding fluoroquinolone resistance. The enzyme was identified as glutamine synthetase (GS); N-acetylnorfloxacin was produced only under conditions associated with GS expression. The GS gene (glnA) was cloned, and the protein (53 kDa) was heterologously expressed and isolated. Optimal conditions and biochemical properties (K(m) and V(max)) of purified GS were characterized; the purified enzyme was inhibited by Mn(2+), Mg(2+), ATP, and ADP. The contribution of GS to norfloxacin resistance was shown by using a norfloxacin-sensitive Escherichia coli strain carrying glnA derived from Microbacterium sp. 4N2-2. The GS of Microbacterium sp. 4N2-2 was shown to act as an N-acetyltransferase for norfloxacin, which produced low-level norfloxacin resistance. Structural and docking analysis identified potential binding sites for norfloxacin at the ADP binding site and for acetyl coenzyme A (acetyl-CoA) at a cleft in GS. The results suggest that environmental bacteria whose enzymes modify fluoroquinolones may be able to survive in the presence of low fluoroquinolone concentrations.

  3. Molecular Cloning of Adenosinediphosphoribosyl Transferase.

    Science.gov (United States)

    1987-09-08

    ACCESSION NO.D,. 03261102F 2312 A~5 11. TITLE (include Securqt Classification) 0 Molecular Cloning of Adenosinediphosphoribosyl Transferase 12. PERSONAL...I’:- AFOSR.Tlt. 8 7 - 0 9 8,2 0IL * pi AFOSR- 85 -0377 PROGRESS REPORT Molecular Cloning of Adenosinediphosphoribosyl Transferase 5." Period of...Pharmacology and the Cardiovascular Research Institute September 8, 1987 .’, 5.’- "’S ". -f, AFOSR - 85 -0377 PROGRESS REPORT Molecular Cloning of

  4. Vibrational Signatures of Isomeric Lithiated N-acetyl-D-hexosamines by Gas-Phase Infrared Multiple-Photon Dissociation (IRMPD) Spectroscopy

    Science.gov (United States)

    Tan, Yanglan; Zhao, Ning; Liu, Jinfeng; Li, Pengfei; Stedwell, Corey N.; Yu, Long; Polfer, Nicolas C.

    2017-03-01

    Three lithiated N-acetyl-D-hexosamine (HexNAc) isomers, N-acetyl-D-glucosamine (GlcNAc), N-acetyl-D-galactosamine (GalNAc), and N-acetyl-D-mannosamine (ManNAc) are investigated as model monosaccharide derivatives by gas-phase infrared multiple-photon dissociation (IRMPD) spectroscopy. The hydrogen stretching region, which is attributed to OH and NH stretching modes, reveals some distinguishing spectral features of the lithium-adducted complexes that are useful in terms of differentiating these isomers. In order to understand the effect of lithium coordination on saccharide structure, and therefore anomericity, chair configuration, and hydrogen bonding networks, the conformational preferences of lithiated GlcNAc, GalNAc, and ManNAc are studied by comparing the experimental measurements with density functional theory (DFT) calculations. The experimental results of lithiated GlcNAc and GalNAc show a good match to the theoretical spectra of low-energy structures adopting a 4 C 1 chair conformation, consistent with this motif being the dominant conformation in condensed-phase monosaccharides. The epimerization effect upon going to lithiated ManNAc is significant, as in this case the 1 C 4 chair conformers give a more compelling match with the experimental results, consistent with their lower calculated energies. A contrasting computational study of these monosaccharides in their neutral form suggests that the lithium cation coordination with Lewis base oxygens can play a key role in favoring particular structural motifs (e.g., a 4 C 1 versus 1 C 4 ) and disrupting hydrogen bond networks, thus exhibiting specific IR spectral features between these closely related lithium-chelated complexes.

  5. Vibrational Signatures of Isomeric Lithiated N-acetyl-D-hexosamines by Gas-Phase Infrared Multiple-Photon Dissociation (IRMPD) Spectroscopy

    Science.gov (United States)

    Tan, Yanglan; Zhao, Ning; Liu, Jinfeng; Li, Pengfei; Stedwell, Corey N.; Yu, Long; Polfer, Nicolas C.

    2017-01-01

    Three lithiated N-acetyl-D-hexosamine (HexNAc) isomers, N-acetyl-D-glucosamine (GlcNAc), N-acetyl-D-galactosamine (GalNAc), and N-acetyl-D-mannosamine (ManNAc) are investigated as model monosaccharide derivatives by gas-phase infrared multiple-photon dissociation (IRMPD) spectroscopy. The hydrogen stretching region, which is attributed to OH and NH stretching modes, reveals some distinguishing spectral features of the lithium-adducted complexes that are useful in terms of differentiating these isomers. In order to understand the effect of lithium coordination on saccharide structure, and therefore anomericity, chair configuration, and hydrogen bonding networks, the conformational preferences of lithiated GlcNAc, GalNAc, and ManNAc are studied by comparing the experimental measurements with density functional theory (DFT) calculations. The experimental results of lithiated GlcNAc and GalNAc show a good match to the theoretical spectra of low-energy structures adopting a 4 C 1 chair conformation, consistent with this motif being the dominant conformation in condensed-phase monosaccharides. The epimerization effect upon going to lithiated ManNAc is significant, as in this case the 1 C 4 chair conformers give a more compelling match with the experimental results, consistent with their lower calculated energies. A contrasting computational study of these monosaccharides in their neutral form suggests that the lithium cation coordination with Lewis base oxygens can play a key role in favoring particular structural motifs (e.g., a 4 C 1 versus 1 C 4 ) and disrupting hydrogen bond networks, thus exhibiting specific IR spectral features between these closely related lithium-chelated complexes.

  6. Effects of N-acetyl-cysteine on endothelial function and inflammation in patients with type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    David J. Cohen

    2009-04-01

    Full Text Available Endothelial dysfunction has been associated with premature vascular disease. There is increasing data that N-acetyl-cysteine (NAC may prevent or improve endothelial dysfunction. The aim of this study was to assess the effects of NAC on endothelial function in patients with type 2 diabetes mellitus, a population at high risk for endothelial dysfunction. Twenty-four patients with diabetes mellitus were assigned randomly to initial therapy with either 900 mg NAC or placebo twice daily in a double-blind, cross-over study design. Flow-mediated vasodilation (FMD of the brachial artery was assessed at baseline, after four weeks of therapy, after a four-week wash-out period, and after another four weeks on the opposite treatment. Plasma and red blood cell glutathione levels and high-sensitivity C-reactive protein (CRP were measured at all four visits. At baseline, FMD was moderately impaired (3.7±2.9%. There was no significant change in FMD after four weeks of NAC therapy as compared to placebo (0.1±3.6% vs. 1.2±4.2%. Similarly, there was no significant change in glutathione levels. However, median CRP decreased from 2.35 to 2.14 mg/L during NAC therapy (p=0.04, while it increased from 2.24 to 2.65 mg/L with placebo. No side effects were noted during the treatment period. In this double-blind, randomized cross-over study, four weeks of oral NAC therapy failed to improve endothelial dysfunction in patients with diabetes mellitus. However, NAC therapy decreased CRP levels, suggesting that this compound may have some efficacy in reducing systemic inflammation.

  7. Development and characterization of new and scalable topical formulations containing N-acetyl-d-glucosamine-loaded solid lipid nanoparticles.

    Science.gov (United States)

    Marto, Joana; Sangalli, Cecilia; Capra, Priscilla; Perugini, Paola; Ascenso, Andreia; Gonçalves, Lídia; Ribeiro, Helena

    2017-11-01

    N-Acetyl-d-glucosamine (NAG) has been recently considered for topical treatment of hyperpigmentation disorders due to its inhibitory effect on thyrosinase enzymes in melanocytes. NAG is a precursor of hyaluronic acid, increasing its amount in skin, and consequently, preserving the skin hydration and elasticity. It may also act as an emulsion stabilizer. Solid lipid nanoparticles (SLN) are advanced delivery systems successfully used in pharmaceutical and cosmetic formulations for the improvement of active molecules penetration into the skin. Therefore, this work aimed to develop and characterize stable and scalable topical formulations containing NAG-loaded SLN. NAG was incorporated in SLN which were prepared by two high shear homogenizers and characterized regarding its morphology and particle size by transmission electron microscopy and photon correlation spectroscopy, respectively. Oil emulgel and hydrogel were used as carriers of NAG-loaded SLN. Several parameters were evaluated, including the droplet size distribution, rheology, pH and topical delivery by different techniques. It was observed that SLN size was significantly dependent on NAG incorporation and homogenization process. Most tested SLN parameters appeared to be quite suitable, that is, spherical and well-defined SLN with approximately 258 nm and -30 mV. Hereafter, both gels containing SLN presented a pseudoplastic flow. Emulgel formulation containing NAG-loaded SLN allowed a higher NAG permeation through the SC compared to the respective control (about 0.8 μgcm(-2 )h(-1)). According to the results obtained, it can be suggested that NAG acts as an emulsion stabilizer. This stabilization was also particularly dependent on the homogenizer type which is quite important for scale-up process. This study demonstrated the potential of scalable SLN formulations to improve NAG topical delivery contributing to the improvement of skin properties on several skin disorders.

  8. Ameliorative effect of N-acetyl cysteine on alpha-cypermethrin-induced pulmonary toxicity in male rats.

    Science.gov (United States)

    Arafa, Manar Hamed; Mohamed, Dalia AbdElmoain; Atteia, Hebatallah Husseini

    2015-01-01

    Alpha-cypermethrin (α-CYP) is one of the most widely used insecticides. It may become an air pollutant and adversely affect the health. The present study was designed to determine whether treatment with N-acetyl cysteine (NAC), a well-known antioxidant, can be useful for the management of the deleterious effects of α-CYP on lung tissues. For this purpose, thirty two male rats were divided into four different groups (eight rats for each). Group (I) gavaged with corn oil (control group), group (II) gavaged daily with NAC (150 mg kg(-1) body weight), group (III) gavaged with α-CYP (14.5 mg kg(-1) body weight/day, dissolved in corn oil), group (IV) gavaged with NAC then with α-CYP 2 h later for 12 weeks. α-CYP significantly increased serum lactate dehydrogenase (LDH) and pulmonary malondialdehyde (MDA) levels, while decreased the activities of catalase (CAT) and superoxide dismutase (SOD) as well as reduced glutathione (GSH) content in lung. It also provoked higher levels of serum nitric oxide (NO), lung interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), hydroxyproline (Hyp) as well as heme oxygenase-1 (HO-1), inducible nitric oxide synthase (iNOS) and nuclear factor-kappa B (NF-К B) gene expression in lung tissues. Histopathological alterations in lung with congestion, cellular infiltration, necrotic changes and thickening of inter-alveolar septa were observed following α-CYP administration. NAC reduced the adverse effects of α-CYP on lung tissues and improved the histological architecture of lung since it showed antioxidant, anti-inflammatory and antifibrotic effects on lung tissues. Our results indicate that NAC exerts a potent protective effect against α-CYP-induced oxidative damage and inflammation in lung tissues.

  9. The influence of N-acetyl-l-cysteine on damage of porcine oocyte exposed to zearalenone in vitro.

    Science.gov (United States)

    Lai, Fang-Nong; Ma, Jun-Yu; Liu, Jing-Cai; Wang, Jun-Jie; Cheng, Shun-Feng; Sun, Xiao-Feng; Li, Lan; Li, Bo; Nyachoti, Charles Martin; Shen, Wei

    2015-12-01

    Zearalenone (ZEA), one of the mycotoxins produced by Fusarium fungi, impacts porcine reproduction by interfering with the estrogen signaling pathway. Previous studies have shown that ZEA inhibits porcine oocyte maturation through the formation of aberrant spindle. To explore the effect of ZEA on porcine oocyte meiotic maturation, the extent of both nuclear and cytoplasmic maturation was examined in this study. Compared with control group, presence of ZEA (3 μM) during oocyte maturation, significantly inhibited the polar body extrusions from 71% to 51%, and significantly increased intracellular reactive oxygen species (ROS) level (12.01 vs. 5.89). Intracellular glutathione (GSH) content in ZEA treatment group was lower than in the control group (1.08 pmol/oocyte vs. 0.18 pmol/oocyte), and cortical granules of cortical area distributed oocytes were reduced (88% vs. 62%). ZEA decreases cumulus expansion in both morphology and mRNA level (HAS2, PTX3, TNFAIP6 and CX43). Addition of N-acetyl-l-cysteine (NAC) to the oocyte maturation media reversed the ZEA-induced inhibition of polar body extrusion (from 69% to 81%), up-regulated ROS (from 7.9 to 6.5), down-regulated GSH content (from 0.16 to 0.82 pmol/oocyte) and recovered cumulus cells expansion in morphology and mRNA level. It is concluded that ZEA affects both oocyte nucleus and cytoplasmic maturation during in vitro maturation, and NAC can reverse these damages to some extent. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. N-acetyl-cysteine and prostaglandin. Comparable protection against experimental ethanol injury in the stomach independent of mucus thickness.

    Science.gov (United States)

    Henagan, J M; Smith, G S; Schmidt, K L; Miller, T A

    1986-12-01

    The role of barrier mucus in mediating the protective effects of 16,16 dimethyl PGE2 (dm PGE2) against ethanol-induced gastric injury, with and without concomitant treatment with N-acetyl-cysteine (NAC), a potent mucolytic agent, was evaluated. Fasted rats were orally administered either saline, 10 micrograms/kg dm PGE2, 20% NAC, or 10 micrograms/kg dm PGE2 plus 20% NAC. In the first study, the rats were killed 15 minutes later and their stomachs were removed and assayed for barrier mucus adherent to the gastric wall using the Alcian blue technique. In the second study, the rats were orally given 2 mL of absolute ethanol (EtOH) after receiving one of these pretreatment regimens, and 5 minutes later they were killed and their stomachs were evaluated histologically by light microscopy for the magnitude of EtOH injury. Although NAC significantly reduced the thickness of barrier mucus by 76% when compared with control animals, it did not adversely affect the ability of dm PGE2 to spare the deep epithelium from injury by EtOH. In fact, NAC was as effective a protective agent as dm PGE2. Neither agent prevented damage to the surface epithelium by EtOH, verifying previous studies regarding the protective effects of prostaglandins. These results indicate that both dm PGE2 and NAC prevent EtOH-induced damage to the deeper layers of the gastric mucosa independent of mucus gel layer thickness, suggesting that other mechanisms than mucus are involved in mediating this protection.

  11. Rapid transport of muco-inert nanoparticles in cystic fibrosis sputum treated with N-acetyl cysteine.

    Science.gov (United States)

    Suk, Jung Soo; Lai, Samuel K; Boylan, Nicholas J; Dawson, Michelle R; Boyle, Michael P; Hanes, Justin

    2011-02-01

    Sputum poses a critical diffusional barrier that strongly limits the efficacy of drug and gene carriers in the airways of individuals with cystic fibrosis (CF). Previous attempts to enhance particle penetration of CF sputum have focused on either reducing its barrier properties via mucolytics, or decreasing particle adhesion to sputum constituents by coating the particle surface with non-mucoadhesive polymers, including polyethylene glycol (PEG). Neither approach has enabled particles to penetrate expectorated sputum at rates previously observed for non-mucoadhesive nanoparticles in human cervicovaginal mucus. Here, we sought to investigate whether a common mucolytic, N-acetyl cysteine (NAC), in combination with dense PEG coatings on particles, can synergistically enhance particle penetration across fresh undiluted CF sputum. We used high-resolution multiple particle tracking to measure the diffusion of uncoated and PEG-coated nanoparticles in native and NAC-treated CF sputum. We discovered that 200 nm particles, if densely coated with PEG, were able to penetrate CF sputum pretreated with NAC with average speeds approaching their theoretical speeds in water. Based on the rapid penetration of PEG-coated particles in NAC-treated sputum, we determined that the average spacing between sputum mesh elements was increased from 145 ± 50 nm to 230 ± 50 nm upon NAC treatment. Mathematical models based on particle transport rates suggest as much as 75 and 30% of 200 and 500 nm PEG-coated particles, respectively, may penetrate a physiologically thick NAC-treated CF sputum layer within 20 min. Uncoated particles were trapped in CF sputum pretreated with NAC nearly to the same extent as in native sputum, suggesting that NAC treatment alone offered little improvement to particle penetration. NAC facilitated rapid diffusion of PEG-coated, muco-inert nanoparticles in CF sputum. Our results provide a promising strategy to improve drug and gene carrier penetration in CF sputum

  12. N-Acetyl-L-Cysteine inhibits the development of glucose intolerance and hepatic steatosis in diabetes-prone mice

    Science.gov (United States)

    Falach-Malik, Alona; Rozenfeld, Hava; Chetboun, Moria; Rozenberg, Konstantin; Elyasiyan, Uriel; Sampson, Sanford R; Rosenzweig, Tovit

    2016-01-01

    Oxidative stress is associated with different pathological conditions, including glucose intolerance and type 2 diabetes (T2D), however studies had failed to prove the benefits of antioxidants in T2D. Aim: On the assumption that the failure to demonstrate such anti-diabetic effects is a result of sub-optimal or excessive antioxidant dosage, we aimed to clarify the dose-response effect of the antioxidant N-Acetyl-L-Cysteine (NAC) on the progression of T2D in-vivo. Methods: Experiments were conducted on KK-Ay mice and HFD-fed mice given NAC at different concentrations (200-1800 and 60-600 mg/kg/day, respectively). Glucose and insulin tolerance tests were performed and plasma insulin and lipid peroxidation were measured. Insulin signaling pathway was followed in muscle and liver. Hepatic TG accumulation and mRNA expression of genes involved in glucose metabolism were measured. Results: While 600-1800 mg/kg/day NAC all improved glucose tolerance in KK-Ay mice, only the 1200 mg/kg/day treatment increased insulin sensitivity. Hepatic function was not affected, however; microsteatosis rather than macrosteatosis was observed in NAC-treated mice compared to control. Glucose tolerance was improved in NAC-treated HFD-fed mice as well; the best results obtained with a dose of 400 mg NAC/kg/day. This was followed by lower weight gain and hepatic TG. Plasma lipid peroxidation was not correlated with the glucose-lowering effects of NAC in either model. Conclusion: Identification of the optimal dose of NAC and the population that would benefit the most from such intervention is essential in order to apply preventive and/or therapeutic use of NAC and similar agents in the future. PMID:27725855

  13. Neuroprotective effects of N-acetyl-cysteine and acetyl-L-carnitine after spinal cord injury in adult rats.

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    Amar Karalija

    Full Text Available Following the initial acute stage of spinal cord injury, a cascade of cellular and inflammatory responses will lead to progressive secondary damage of the nerve tissue surrounding the primary injury site. The degeneration is manifested by loss of neurons and glial cells, demyelination and cyst formation. Injury to the mammalian spinal cord results in nearly complete failure of the severed axons to regenerate. We have previously demonstrated that the antioxidants N-acetyl-cysteine (NAC and acetyl-L-carnitine (ALC can attenuate retrograde neuronal degeneration after peripheral nerve and ventral root injury. The present study evaluates the effects of NAC and ALC on neuronal survival, axonal sprouting and glial cell reactions after spinal cord injury in adult rats. Tibial motoneurons in the spinal cord were pre-labeled with fluorescent tracer Fast Blue one week before lumbar L5 hemisection. Continuous intrathecal infusion of NAC (2.4 mg/day or ALC (0.9 mg/day was initiated immediately after spinal injury using Alzet 2002 osmotic minipumps. Neuroprotective effects of treatment were assessed by counting surviving motoneurons and by using quantitative immunohistochemistry and Western blotting for neuronal and glial cell markers 4 weeks after hemisection. Spinal cord injury induced significant loss of tibial motoneurons in L4-L6 segments. Neuronal degeneration was associated with decreased immunostaining for microtubular-associated protein-2 (MAP2 in dendritic branches, synaptophysin in presynaptic boutons and neurofilaments in nerve fibers. Immunostaining for the astroglial marker GFAP and microglial marker OX42 was increased. Treatment with NAC and ALC rescued approximately half of the motoneurons destined to die. In addition, antioxidants restored MAP2 and synaptophysin immunoreactivity. However, the perineuronal synaptophysin labeling was not recovered. Although both treatments promoted axonal sprouting, there was no effect on reactive astrocytes

  14. N-acetyl cysteine mitigates the acute effects of cocaine-induced toxicity in astroglia-like cells.

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    Ramesh B Badisa

    Full Text Available Cocaine has a short half-life of only about an hour but its effects, predominantly on the central nervous system (CNS, are fairly long-lasting. Of all cells within the CNS, astrocytes may be the first to display cocaine toxicity owing to their relative abundance in the brain. Cocaine entry could trigger several early response changes that adversely affect their survival, and inhibiting these changes could conversely increase their rate of survival. In order to identify these changes and the minimal concentrations of cocaine that can elicit them in vitro, rat C6 astroglia-like cells were treated with cocaine (2-4 mM for 1h and assayed for alterations in gross cell morphology, cytoplasmic vacuolation, viability, reactive oxygen species (ROS generation, glutathione (GSH levels, cell membrane integrity, F-actin cytoskeleton, and histone methylation. We report here that all of the above identified features are significantly altered by cocaine, and may collectively represent the key pathology underlying acute toxicity-mediated death of astroglia-like cells. Pretreatment of the cells with the clinically available antioxidant N-acetyl cysteine (NAC, 5 mM for 30 min inhibited these changes during subsequent application of cocaine and mitigated cocaine-induced toxicity. Despite repeated cocaine exposure, NAC pretreated cells remained highly viable and post NAC treatment also increased viability of cocaine treated cells to a smaller yet significant level. We show further that this alleviation by NAC is mediated through an increase in GSH levels in the cells. These findings, coupled with the fact that astrocytes maintain neuronal integrity, suggest that compounds which target and mitigate these early toxic changes in astrocytes could have a potentially broad therapeutic role in cocaine-induced CNS damage.

  15. Structural Diversity Within the Mononuclear and Binuclear Active Sites of N-Acetyl-D-Glucosamine-6-Phosphate Deacetylase

    Energy Technology Data Exchange (ETDEWEB)

    Hall,R.; Brown, S.; Fedorov, A.; Fedorov, E.; Xu, C.; Babbitt, P.; Almo, S.; Raushel, F.

    2007-01-01

    NagA catalyzes the hydrolysis of N-acetyl-D-glucosamine-6-phosphate to D-glucosamine-6-phosphate and acetate. X-ray crystal structures of NagA from Escherichia coli were determined to establish the number and ligation scheme for the binding of zinc to the active site and to elucidate the molecular interactions between the protein and substrate. The three-dimensional structures of the apo-NagA, Zn-NagA, and the D273N mutant enzyme in the presence of a tight-binding N-methylhydroxyphosphinyl-D-glucosamine-6-phosphate inhibitor were determined. The structure of the Zn-NagA confirms that this enzyme binds a single divalent cation at the beta-position in the active site via ligation to Glu-131, His-195, and His-216. A water molecule completes the ligation shell, which is also in position to be hydrogen bonded to Asp-273. In the structure of NagA bound to the tight binding inhibitor that mimics the tetrahedral intermediate, the methyl phosphonate moiety has displaced the hydrolytic water molecule and is directly coordinated to the zinc within the active site. The side chain of Asp-273 is positioned to activate the hydrolytic water molecule via general base catalysis and to deliver this proton to the amino group upon cleavage of the amide bond of the substrate. His-143 is positioned to help polarize the carbonyl group of the substrate in conjunction with Lewis acid catalysis by the bound zinc. The inhibitor is bound in the {alpha}-configuration at the anomeric carbon through a hydrogen bonding interaction of the hydroxyl group at C-1 with the side chain of His-251. The phosphate group of the inhibitor attached to the hydroxyl at C-6 is ion paired with Arg-227 from the adjacent subunit. NagA from Thermotoga maritima was shown to require a single divalent cation for full catalytic activity.

  16. Expression of N-acetyl-glucosamine-6-O-sulfotransferase in the endometrium of implantation window stage from infertile patients

    Institute of Scientific and Technical Information of China (English)

    Dai Hui-hua; Zhang Hong-mei; Liu Jia-yin

    2007-01-01

    Objective: To observe the expression of N-acetyl-glucosamine-6-O-sulfotransferase (GN-6-ST)in the endometrium during the window stage of implantation from infertile women before IVF-ET treatment, we compared the GN-6-ST gene expression level between the women with succeeded and failed implantation, and investigated the roles of selectin and its ligands in the embryo implantation.Methods: The hysteroscopy and endometrial biopsies were performed in patients prior to undergoing IVF-ET treatment in the IVF Center of the First Affiliated Hospital of Nanjing Medical University from July 2004 to March 2005.Fourteen patients who succeeded in implantation were taken as study group, while the 28 infertile patients with failed implantation served as control group.The RT-PCR method was used to detect the mRNA levels of N-ac-etyl-glucosamine-6-O-sulfotransferase in the endometrium during the window stage of imp-lantation of the women from both groups.Results: For these infertile patients with succeeded implantation, the average mRNA expression level of acetylglucosamine-6-O-sulfotransferase in the endometrium during the window stage of implantation was (0.65±0.33),while for those with failed implantation cycle, the average mRNA expression level was (0.41±0.36), which was significantly lower than that of study group, P<0.05.Conclusions: The combination of the selectin and ligands may play a role in the embryo implantation capacibility.

  17. Consumption of fructose- but not glucose-sweetened beverages for 10 weeks increases circulating concentrations of uric acid, retinol binding protein-4, and gamma-glutamyl transferase activity in overweight/obese humans

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    Cox Chad L

    2012-07-01

    Full Text Available Abstract Background Prospective studies in humans examining the effects of fructose consumption on biological markers associated with the development of metabolic syndrome are lacking. Therefore we investigated the relative effects of 10 wks of fructose or glucose consumption on plasma uric acid and RBP-4 concentrations, as well as liver enzyme (AST, ALT, and GGT activities in men and women. Methods As part of a parallel arm study, older (age 40–72, overweight and obese male and female subjects (BMI 25–35 kg/m2 consumed glucose- or fructose-sweetened beverages providing 25% of energy requirements for 10 wks. Fasting and 24-h blood collections were performed at baseline and following 10 wks of intervention and plasma concentrations of uric acid, RBP-4 and liver enzyme activities were measured. Results Consumption of fructose, but not glucose, led to significant increases of 24-h uric acid profiles (P P = 0.012, as well as plasma GGT activity (P = 0.04. Fasting plasma uric acid concentrations increased in both groups; however, the response was significantly greater in subjects consuming fructose (P = 0.002 for effect of sugar. Within the fructose group male subjects exhibited larger increases of RBP-4 levels than women (P = 0.024. Conclusions These findings suggest that consumption of fructose at 25% of energy requirements for 10 wks, compared with isocaloric consumption of glucose, may contribute to the development of components of the metabolic syndrome by increasing circulating uric acid, GGT activity, suggesting alteration of hepatic function, and the production of RBP-4.

  18. Evaluation of efficacy of vitamin E and N-acetyl cysteine in gentamicin-induced nephrotoxicity in rats.

    Science.gov (United States)

    Patel Manali, Bhalchandra; Deshpande, Shrikalp; Shah, Gaurang

    2011-01-01

    Gentamicin (GM), an aminoglycoside, is widely employed in clinical practice for the treatment of serious gram-negative infections. The clinical utility of GM is limited by the frequent incidence of acute renal failure. This study was designed to investigate treatment and posttreatment renoprotective potential of vitamin E and N-acetyl cysteine (NAC) against GM-induced oxidative stress and renal dysfunction. Male Sprague-Dawley rats were divided into six groups: first group is the control group that received olive oil (0.1 mL/100 g B.W.), second is the one that was treated with GM (80 mg/kg/i.p./8 days), third is the one that was treated with GM (80 mg/kg/i.p./8 days) and vitamin E (50 mg/kg/i.p./8 days), fourth is the one that was treated with GM (80 mg/kg/i.p./8 days) and NAC (50 mg/kg/i.p./8 days), fifth is the one that was treated with GM (80 mg/kg/i.p./8 days), vitamin E (50 mg/kg/i.p./8 days), and NAC (50 mg/kg/i.p./8 days), and sixth is the one that was treated with GM initially for 8 days (at 80 mg/kg/i.p.) after which vitamin E (at 50 mg/kg/i.p.) and NAC (at 50 mg/kg/i.p.) were administered for 8 days. Serum creatinine, blood urea nitrogen, serum glucose, renal malondialdehyde, renal reduced glutathione, urine sodium, fractional excretion of sodium, and histopathological examination of kidney were performed after treatment. Gentamicin treatment caused nephrotoxicity as evidenced by marked elevation in serum creatinine, blood urea nitrogen, renal malondialdehyde, urine sodium, and fractional excretion of sodium. Study of renal morphology showed marked loss of epithelium in proximal convoluted tubule, inflammatory infiltrate in the form of lymphocytes, mainly in interstitium. Treatment and posttreatment with vitamin E and NAC significantly restored renal functions, reduced lipid peroxidation, enhanced reduced glutathione level, and restored the biochemical parameters. The results of this study demonstrate the therapeutic potential of vitamin E and NAC in

  19. N-Acetyl-cysteine causes analgesia by reinforcing the endogenous activation of type-2 metabotropic glutamate receptors

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    Bernabucci Matteo

    2012-10-01

    Full Text Available Abstract Background Pharmacological activation of type-2 metabotropic glutamate receptors (mGlu2 receptors causes analgesia in experimental models of inflammatory and neuropathic pain. Presynaptic mGlu2 receptors are activated by the glutamate released from astrocytes by means of the cystine/glutamate antiporter (System xc- or Sxc-. We examined the analgesic activity of the Sxc- activator, N-acetyl-cysteine (NAC, in mice developing inflammatory or neuropathic pain. Results A single injection of NAC (100 mg/kg, i.p. reduced nocifensive behavior in the second phase of the formalin test. NAC-induced analgesia was abrogated by the Sxc- inhibitor, sulphasalazine (8 mg/kg, i.p. or by the mGlu2/3 receptor antagonist, LY341495 (1 mg/kg, i.p.. NAC still caused analgesia in mGlu3−/− mice, but was inactive in mGlu2−/− mice. In wild-type mice, NAC retained the analgesic activity in the formalin test when injected daily for 7 days, indicating the lack of tolerance. Both single and repeated injections of NAC also caused analgesia in the complete Freund’s adjuvant (CFA model of chronic inflammatory pain, and, again, analgesia was abolished by LY341495. Data obtained in mice developing neuropathic pain in response to chronic constriction injury (CCI of the sciatic nerve were divergent. In this model, a single injection of NAC caused analgesia that was reversed by LY341495, whereas repeated injections of NAC were ineffective. Thus, tolerance to NAC-induced analgesia developed in the CCI model, but not in models of inflammatory pain. The CFA and CCI models differed with respect to the expression levels of xCT (the catalytic subunit of Sxc- and activator of G-protein signaling type-3 (AGS3 in the dorsal portion of the lumbar spinal cord. CFA-treated mice showed no change in either protein, whereas CCI mice showed an ipislateral reduction in xCT levels and a bilateral increase in AGS3 levels in the spinal cord. Conclusions These data demonstrate that

  20. N-Acetyl Cysteine May Support Dopamine Neurons in Parkinson's Disease: Preliminary Clinical and Cell Line Data.

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    Daniel A Monti

    Full Text Available The purpose of this study was to assess the biological and clinical effects of n-acetyl-cysteine (NAC in Parkinson's disease (PD.The overarching goal of this pilot study was to generate additional data about potentially protective properties of NAC in PD, using an in vitro and in vivo approach. In preparation for the clinical study we performed a cell tissue culture study with human embryonic stem cell (hESC-derived midbrain dopamine (mDA neurons that were treated with rotenone as a model for PD. The primary outcome in the cell tissue cultures was the number of cells that survived the insult with the neurotoxin rotenone. In the clinical study, patients continued their standard of care and were randomized to receive either daily NAC or were a waitlist control. Patients were evaluated before and after 3 months of receiving the NAC with DaTscan to measure dopamine transporter (DAT binding and the Unified Parkinson's Disease Rating Scale (UPDRS to measure clinical symptoms.The cell line study showed that NAC exposure resulted in significantly more mDA neurons surviving after exposure to rotenone compared to no NAC, consistent with the protective effects of NAC previously observed. The clinical study showed significantly increased DAT binding in the caudate and putamen (mean increase ranging from 4.4% to 7.8%; p<0.05 for all values in the PD group treated with NAC, and no measurable changes in the control group. UPDRS scores were also significantly improved in the NAC group (mean improvement of 12.9%, p = 0.01.The results of this preliminary study demonstrate for the first time a potential direct effect of NAC on the dopamine system in PD patients, and this observation may be associated with positive clinical effects. A large-scale clinical trial to test the therapeutic efficacy of NAC in this population and to better elucidate the mechanism of action is warranted.ClinicalTrials.gov NCT02445651.

  1. Effects of N-acetyl-L-cysteine on gene expression of antioxidant enzymes in yeast cells after irradiation

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    Kim, Jin Kyu; Park, Ji Young; Ryu, Tae Ho; Roh, Chang Hyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Nili, Mohammad [Dawnesh Radiation Research Institute, Barcelona (Spain)

    2012-04-15

    Ionizing radiation induces water radiolysis, which generates highly reactive hydroxyl radicals. Reactive oxygen species (ROS) cause apoptosis and cell damage. When exposed to ionizing radiation, cells activates ROS scavenging detoxifying enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase. SOD scavenges superoxide radicals by catalyzing the conversion of two of these radicals into hydrogen peroxide and molecular oxygen. The hydrogen peroxide formed by superoxide dismutase and by other processes is scavenged by catalase, a ubiquitous heme protein that catalyzes the dismutation of hydrogen peroxide into water and molecular oxygen. Yeast has two catalase and three GPx proteins. The biochemical function of GPx is to reduce lipid-hydroperoxides to their corresponding alcohols and to reduce free hydrogen peroxide to water. N-acetylL-cysteine (NAC) having a thiol, a precursor for glutathione (GSH), is known as one of the antioxidants. NAC prevents the depletion of GSH by radiation, increases the production of GSH, and improves enzymes activity and alkaline phosphatase. In this study, the role of NAC as an antioxidant and a radioprotector was examined on cell survival, transcriptional level, and protein level. through observing viability of cells, analyzing the gene expression of antioxidant enzyme, measuring the SOD activity and intracellular GSH levels in yeast W303-1A strain The cell viability of haploid S. cerevisiae W303-1A strain was reduced significantly at the low dose (10∼30 Gy). The half-lethal dose of the strain was about 20 Gy. The CFU assay result confirmed that NAC could not rescue the cells from radiation-induced death. When irradiated with 100 Gy, an increase in the transcriptional expression was observed in the antioxicant genes. The expression of these genes decreased by treatment of NAC in irradiated cells. NAC decline SOD activity and intracellular GSH levels. The present study shows that NAC can directly scavenge

  2. Glutathione transferases and neurodegenerative diseases.

    Science.gov (United States)

    Mazzetti, Anna Paola; Fiorile, Maria Carmela; Primavera, Alessandra; Lo Bello, Mario

    2015-03-01

    There is substantial agreement that the unbalance between oxidant and antioxidant species may affect the onset and/or the course of a number of common diseases including Parkinson's and Alzheimer's diseases. Many studies suggest a crucial role for oxidative stress in the first phase of aging, or in the pathogenesis of various diseases including neurological ones. Particularly, the role exerted by glutathione and glutathione-related enzymes (Glutathione Transferases) in the nervous system appears more relevant, this latter tissue being much more vulnerable to toxins and oxidative stress than other tissues such as liver, kidney or muscle. The present review addresses the question by focusing on the results obtained by specimens from patients or by in vitro studies using cells or animal models related to Parkinson's and Alzheimer's diseases. In general, there is an association between glutathione depletion and Parkinson's or Alzheimer's disease. In addition, a significant decrease of glutathione transferase activity in selected areas of brain and in ventricular cerebrospinal fluid was found. For some glutathione transferase genes there is also a correlation between polymorphisms and onset/outcome of neurodegenerative diseases. Thus, there is a general agreement about the protective effect exerted by glutathione and glutathione transferases but no clear answer about the mechanisms underlying this crucial role in the insurgence of neurodegenerative diseases.

  3. Regulating effect of N-acetyl cysteine adjuvant therapy on airway inflammation, remodeling and so on in patients with stable COPD

    Institute of Scientific and Technical Information of China (English)

    Xiao-Feng Zhao

    2016-01-01

    Objective:To analyze the regulating effect of N-acetyl cysteine adjuvant therapy on airway inflammation, remodeling and so on in patients with stable COPD.Methods: A total of 108 cases of COPD patients who were treated in our hospital were included for study and were in stable phase after detection. According to different treatment methods, they were divided into control group 58 cases who received routine treatment and observation group 50 cases who received additional N-acetyl cysteine adjuvant therapy. Differences in levels of serum inflammation-related factors, airway remodeling indicators, Keap1-Nrf2-ARE signaling pathway, oxidation-antioxidation levels, etc were compared between two groups after treatment.Results: Serum MIP-1α, sTREM-1, IL-13, IL-8 and IP-10 values of observation group after treatment were lower than those of control group; serum TGF-β1 and Ang-Ⅱvalues of observation group after treatment were lower than those of control group, Ang-Ⅰ value was higher than that of control group and lesion bronchia T, WA and WA% values were lower than those of control group; Keap1, Nrf2 and ARE values in serum and induced sputum of observation group were higher than those of control group; serum MDA and LPO values of observation group were lower than those of control group while SOD, GSH-Px and T-AOX values were higher than those of control group.Conclusion:N-acetyl cysteine adjuvant therapy for patients with stable COPD optimizes airway inflammation, remodeling and so on, and is of positive significance in controlling long-term disease, improving outcome and so on.

  4. Antifibrotic medication using a combination of N-acetyl-L-cystein (NAC) and ACE inhibitors can prevent the recurrence of Dupuytren's disease.

    Science.gov (United States)

    Knobloch, Karsten; Redeker, Joern; Vogt, Peter M

    2009-11-01

    Dupuytren's disease is a progress fibromatosis of unknown origin first described in 1831. Nonoperative treatment options have been suggested involving radiation therapy, vitamin E, local injection therapy suing calcium channel blockers, interferon, corticosteroids or collagenase. Transforming growth factor-beta1 (TGF-beta1) and its downstream Smad signalling system is well established as a key player during fibrogenesis. A number of in vitro experiments have been assessed the blockade of TGF-beta1 and TGF-beta 2. Clinically, a number of antifibrotic agents are available such as N-acetyl-L-cysteins (NAC) as well as angiotensin-converting enzyme (ACE) inhibitors or AT II antagonists. However, to date none of the well known substances has been tested clinically in fibromatosis such as Dupuytren's disease especially to prevent recurrences after surgical release. Antifibrotic medication using a combination of N-acetyl-L-cystein (NAC) and ACE inhibitor can prevent the recurrence of Dupyutren's disease. Given the fact that recurrence rate in Dupuytren's disease is high and unpredictable after surgical release, an antifibrotic intervention might be worthwhile to consider in the clinical setting. Antifibrotic agents inhibit TGF-beta1, which play a key role in fibromatosis. Thus, antifibrotic medication might reduce the recurrence rate in fibromatosis such as Dupuytren's disease in a clinical significant way.

  5. Quantitative determination of sulfisoxazole and its three N-acetylated metabolites using HPLC-MS/MS, and the saturable pharmacokinetics of sulfisoxazole in mice.

    Science.gov (United States)

    Oh, Kyungsoo; Baek, Moon-Chang; Kang, Wonku

    2016-09-10

    Sulfisoxazole (SFX) is still used in combination with trimethoprim in cattle despite adverse drug reactions (e.g., urolithiasis). Recently, SFX is known to be a promising repositioned drug candidate for pulmonary hypertension and cancer. We developed a simultaneous determination method of SFX and its N-acetylated metabolites (N(1)-acetyl SFX, N1AS; N(4)-acetyl SFX, N4AS; diacetyl SFX, DAS) using HPLC-MS/MS for the first time, and examined the pharmacokinetics of SFX in mice. N1AS and DAS were converted rapidly to SFX and N4AS, respectively, in mouse plasma. The time courses of plasma SFX and N4AS concentrations were well-characterised following the oral administration of SFX to mice. The absorption, metabolism, and/or excretion of SFX given at >700mg/kg may be saturable, and in contrast to humans and rats, the extent of systemic exposure of mice to N4AS was much greater than that of SFX. Interestingly, the acetyl groups at both N1- and N4-positions were degraded during the ionisation required to generate precursor ions. In additional experiments the carboxyl group of N-acetyl-5-aminosalicylic acid (NA5AS) was lost instead of the acetyl group during the ionisation, and acetaminophen (AAP) appeared. As the acetyl and carboxyl groups of some substances can be degraded during ionisation in the mass spectrometer, caution is appropriate when it is sought to simultaneously quantify similar structures containing these moieties; chromatographic separation is essential.

  6. N-acetyl ornithine deacetylase is a moonlighting protein and is involved in the adaptation of Entamoeba histolytica to nitrosative stress

    Science.gov (United States)

    Shahi, Preeti; Trebicz-Geffen, Meirav; Nagaraja, Shruti; Hertz, Rivka; Alterzon-Baumel, Sharon; Methling, Karen; Lalk, Michael; Mazumder, Mohit; Samudrala, Gourinath; Ankri, Serge

    2016-01-01

    Adaptation of the Entamoeba histolytica parasite to toxic levels of nitric oxide (NO) that are produced by phagocytes may be essential for the establishment of chronic amebiasis and the parasite’s survival in its host. In order to obtain insight into the mechanism of E. histolytica’s adaptation to NO, E. histolytica trophozoites were progressively adapted to increasing concentrations of the NO donor drug, S-nitrosoglutathione (GSNO) up to a concentration of 110 μM. The transcriptome of NO adapted trophozoites (NAT) was investigated by RNA sequencing (RNA-seq). N-acetyl ornithine deacetylase (NAOD) was among the 208 genes that were upregulated in NAT. NAOD catalyzes the deacetylation of N-acetyl-L-ornithine to yield ornithine and acetate. Here, we report that NAOD contributes to the better adaptation of the parasite to nitrosative stress (NS) and that this function does not depend on NAOD catalytic activity. We also demonstrated that glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is detrimental to E. histolytica exposed to NS and that this detrimental effect is neutralized by NAOD or by a catalytically inactive NAOD (mNAOD). These results establish NAOD as a moonlighting protein, and highlight the unexpected role of this metabolic enzyme in the adaptation of the parasite to NS. PMID:27808157

  7. A Ribbon-like Structure in the Ejective Organelle of the Green Microalga Pyramimonas parkeae (Prasinophyceae) Consists of Core Histones and Polymers Containing N-acetyl-glucosamine.

    Science.gov (United States)

    Yamagishi, Takahiro; Kurihara, Akira; Kawai, Hiroshi

    2015-11-01

    The green microalga, Pyramimonas parkeae (Prasinophyceae) has an ejective organelle containing a coiled ribbon structure resembling the ejectisome in Cryptophyta. This structure is discharged from the cell by a stimulus and extends to form a tube-like structure, but the molecular components of the structure have not been identified. Tricine-SDS-PAGE analysis indicated that the ribbon-like structure of P. parkeae contains some proteins and low molecular acidic polymers. Edman degradation, LC/MS/MS analyses and immunological studies demonstrated that their proteins are core histones (H3, H2A, H2B and H4). In addition, monosaccharide composition analysis of the ribbon-like structures and degradation by lysozyme strongly indicated that the ribbon-like structure consist of β (1-4) linked polymers containing N-acetyl-glucosamine. Purified polymers and recombinant histones formed glob-like or filamentous structures. Therefore we conclude that the ribbon-like structure of P. parkeae mainly consists of a complex of core histones (H3, H2A, H2B and H4) and polymers containing N-acetyl-glucosamine, and suggest to name the ejective organelle in P. parkeae the "histrosome" to distinguish it from the ejectisome in Cryptophyta. Copyright © 2015 Elsevier GmbH. All rights reserved.

  8. Microwave-Assisted Esterification of N-Acetyl-L-Phenylalanine Using Modified Mukaiyama’s Reagents: A New Approach Involving Ionic Liquids

    Directory of Open Access Journals (Sweden)

    Olarongbe Olubajo

    2008-01-01

    Full Text Available Inspired by the concept of ionic liquids (ILs, this study modified the original Mukaiyama’s reagent, 2-chloro-1-methylpyridinium iodide (m.p. 200-dec, from ionic solid into liquids by changing its anion. The esterification of N-acetyl-L-phenylalanine was investigated as a model reaction. The microwave irradiation was more effective in esterifying N-acetyl-L-phenylalanine than the conventional reflux method. The original Mukaiyama’s reagent was modified into ILs through manipulating its anion. However, only non-nucleophilic anions (such as EtSO4- and Tf2N- were favorable since nucleophilic ones (such as CF3COO- and CH3COO- could exchange with chlorine resulting in non-reactive coupling reagents. Two modified Mukaiyama’s compounds (i.e. hydrophilic [2- ClMePy][EtSO4] and hydrophobic [2-ClMePy][Tf2N] have been identified as the best ILtype coupling reagents. The esterification reaction was greatly enhanced by using 1- methylimidazole as the base instead of conventional toxic tertiary amines, and by using excess amount of alcohols as solvents instead of dichloromethane. Overall, the method reported is effective and ‘greener’.

  9. Protective Effects of N-Acetyl-L-cystein on 3,4-Methylene Dioxymethamphetamie-Induced Neurotoxicity in Cerebellum of Male Rats

    Directory of Open Access Journals (Sweden)

    Sara Soleimani Asl

    2011-10-01

    Full Text Available Objective(s: 3-4, methylenedioxymethamphetamine (MDMA causes apoptosis in nervous system and several studies suggest that oxidative stress contributes to MDMA-induced neurotoxicity. The aim of this study is to examine the effects of N-acetyl-L-Cystein (NAC as an antioxidant on MDMA-induced apoptosis. Materials and Methods: 21 Sprague dawley male rats (200-250mg were treated with MDMA (2×0,5mg/kg or MDMA plus NAC (100mg/kg IP for 7 day. After last administration of MDMA, rats were killed, cerebellum was removed and Bax and Bcl-2 expression was assessed by western blotting method. Results: The results of this study showed that MDMA causes up-regulation of Bax and down-regulation of Bcl-2 and NAC administration attenuated MDMA-induced apoptosis. Conclusion: The present study suggests that NAC treatment may improve MDMA-induced neurotoxicity.

  10. EPR investigation of gamma-irradiated L-citrulline, α-methyl-DL-serine, 3-fluoro-DL-valine and N-acetyl-L-cysteine

    Science.gov (United States)

    Osmanoğlu, Y. Emre; Sütçü, Kerem; Başkan, M. Halim

    2017-02-01

    The spectroscopic parameters of the paramagnetic species produced in gamma-irradiated L-citrulline, α-methyl-DL-serine, 3-fluoro-DL-valine and N-acetyl-L-cysteine were investigated at room temperature at a dose of 20 kGy by using EPR technique. The paramagnetic species were attributed to NH2CONH(CH2)3ĊNH2COOH, HOCH2ĊCH3COOH and HOĊHCCH3NH2COOH, CH3CH3ĊCHNH2COOH and SHCH2ĊNHCOCH3COOH radicals, respectively. EPR data of the unpaired electron with the environmental protons and 14N nucleus were used to characterize the contributing radicals produced in gamma irradiated compounds. In this paper, the stability of these compounds at room temperature after irradiation was also studied.

  11. Structural study, NCA, FT-IR, FT-Raman spectral investigations, NBO analysis, thermodynamic functions of N-acetyl-L-phenylalanine

    Science.gov (United States)

    Raja, B.; Balachandran, V.; Revathi, B.

    2015-03-01

    The FT-IR and FT-Raman spectra of N-acetyl-L-phenylalanine were recorded and analyzed. Natural bond orbital analysis has been carried out for various intramolecular interactions that are responsible for the stabilization of the molecule. HOMO-LUMO energy gap has been computed with the help of density functional theory. The statistical thermodynamic functions (heat capacity, entropy, vibrational partition function and Gibbs energy) were obtained for the range of temperature 100-1000 K. The polarizability, first hyperpolarizability, anisotropy polarizability invariant has been computed using quantum chemical calculations. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of the experimental and theoretical spectra values provides important information about the ability of the computational method to describe the vibrational modes.

  12. The concentration of N-acetyl aspartate, creatine + phosphocreatine, and choline in different parts of the brain in adulthood and senium

    DEFF Research Database (Denmark)

    Christiansen, P; Toft, P; Larsson, H B;

    1993-01-01

    The fully relaxed water signal was used as an internal standard in a STEAM experiment to calculate the concentrations of the metabolites: N-acetyl aspartate (NAA), creatine + phosphocreatine (Cr + PCr), and choline (Cho) containing compounds in four different parts of the brain in two age groups....... In the younger age group, the concentration of NAA was significantly higher in the occipital part than in the other three parts of the brain. No significant regional variation was found for any other metabolite concentration. There was a significantly higher concentration of NAA in the occipital part...... of the brain in the younger age group compared to the older one. No significant regional or age dependent variation was found concerning the T1 and T2 relaxation times....

  13. Relative efficacies of alpha-tocopherol, N-acetyl-serotonin, and melatonin in reducing non-enzymatic lipid peroxidation of rat testicular microsomes and mitochondria.

    Science.gov (United States)

    Gavazza, Mariana; Catalá, Angel

    2009-01-01

    In this study, we examined the relative efficacies of alpha-tocopherol, N-acetyl-serotonin, and melatonin in reducing ascorbate-Fe(2+) lipid peroxidation (LPO) of rat testicular microsomes and mitochondria. Special attention was paid to the changes produced on the highly polyunsaturated fatty acids (PUFAs) C20:4 n6 and C22:5 n6. The LPO of testicular microsomes or mitochondria produced a significant decrease of C20:4 n6 and C22:5 n6. Both long-chain PUFAs were protected when the antioxidants were incorporated either in microsomes or mitochondria. By comparison of the IC50 values obtained between alpha-tocopherol and both indolamines, it was observed that alpha-tocopherol was the most efficient antioxidant against the LPO induced by ascorbate-Fe(2+) under experimental conditions in vitro, IC50 values from the inhibition of alpha-tocopherol on the chemiluminescence were higher in microsomes (0.14 mM) than in mitochondria (0.08 mM). The protective effect observed by alpha-tocopherol in rat testis mitochondria was higher compared with microsomes, associated with the higher amount of [C20:4 n6] + [C22:5 n6] in microsomes than that in mitochondria. Melatonin and N-acetyl-serotonin were more effective in inhibiting the LPO in mitochondria than that in microsomes. Thus, a concentration of 1 mM of both indolamines was sufficient to inhibit in approximately 70% of the light emission in mitochondria, whereas a greater dosage of 10 times (10 mM) was necessary to produce the same effect in microsomes. It is proposed that the vulnerability to LPO of rat testicular microsomes and mitochondria in the presence of both indolamines is different because of the different proportion of PUFAs in these organelles.

  14. Identification of Novel Potential β-N-Acetyl-D-Hexosaminidase Inhibitors by Virtual Screening, Molecular Dynamics Simulation and MM-PBSA Calculations

    Directory of Open Access Journals (Sweden)

    Yonghua Wang

    2012-04-01

    Full Text Available Chitinolytic β-N-acetyl-D-hexosaminidases, as a class of chitin hydrolysis enzyme in insects, are a potential species-specific target for developing environmentally-friendly pesticides. Until now, pesticides targeting chitinolytic β-N-acetyl-D-hexosaminidase have not been developed. This study demonstrates a combination of different theoretical methods for investigating the key structural features of this enzyme responsible for pesticide inhibition, thus allowing for the discovery of novel small molecule inhibitors. Firstly, based on the currently reported crystal structure of this protein (OfHex1.pdb, we conducted a pre-screening of a drug-like compound database with 8 × 106 compounds by using the expanded pesticide-likeness criteria, followed by docking-based screening, obtaining 5 top-ranked compounds with favorable docking conformation into OfHex1. Secondly, molecular docking and molecular dynamics simulations are performed for the five complexes and demonstrate that one main hydrophobic pocket formed by residues Trp424, Trp448 and Trp524, which is significant for stabilization of the ligand–receptor complex, and key residues Asp477 and Trp490, are respectively responsible for forming hydrogen-bonding and π–π stacking interactions with the ligands. Finally, the molecular mechanics Poisson–Boltzmann surface area (MM-PBSA analysis indicates that van der Waals interactions are the main driving force for the inhibitor binding that agrees with the fact that the binding pocket of OfHex1 is mainly composed of hydrophobic residues. These results suggest that screening the ZINC database can maximize the identification of potential OfHex1 inhibitors and the computational protocol will be valuable for screening potential inhibitors of the binding mode, which is useful for the future rational design of novel, potent OfHex1-specific pesticides.

  15. The activity of N-acetyl-β-d-hexosaminidase A and B and β-glucuronidase in nasal polyps and hypertrophic nasal concha.

    Science.gov (United States)

    Chojnowska, Sylwia; Minarowska, Alina; Waszkiewicz, Napoleon; Kępka, Alina; Zalewska-Szajda, Beata; Gościk, Elżbieta; Kowal, Krzysztof; Olszewska, Ewa; Konarzewska-Duchnowska, Emilia; Minarowski, Łukasz; Zwierz, Krzysztof; Ładny, Jerzy Robert; Szajda, Sławomir Dariusz

    2014-01-01

    Nasal polyps and hypertrophic lower nasal conchae are common disorders of nasal cavity. The majority of etiopathogenetic theories indicate inflammatory background of polyps and hypertrophic concha. N-acetyl-β-D-hexosaminidase and β-glucuronidase are lysosomal exoglycosidases revealing accelerated activity in inflammatory processes. The aim of the study was to evaluate the catabolism of glycoconjugates in nasal polyps and hypertrophic nasal concha basing on the activity of N-acetyl-β-D-hexosaminidase (HEX) and β-glucuronidase (GLU). Material consisted of nasal polyps taken from 40 patients during polypectomy in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and hypertrophic lower nasal conchae taken from 20 patients during mucotomy. The activity of HEX, HEX A, HEX B and GLU in supernatant of homogenates of nasal polyps and hypertrophic lower nasal concha tissues has been estimated using colorimetric method. Statistically significant decrease has been observed in concentration of the activity (per 1mg of tissue) of HEX (p<0.05), HEX B (p<0.001) and specific activity (per 1mg of protein) of HEX B (p<0.001) in nasal polyps tissue in comparison to hypertrophic lower nasal conchae tissue. Decrease in the activity and specific activity concentration of the majority of examined lysosomal exoglycosidases (increasing in inflammations) in comparison to hypertrophic lower nasal conchae suggests electrolytes disorders and questions the inflammatory background of nasal polyps. Copyright © 2013 Polish Otorhinolaryngology - Head and Neck Surgery Society. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.

  16. Phase II metabolism in human skin: skin explants show full coverage for glucuronidation, sulfation, N-acetylation, catechol methylation, and glutathione conjugation.

    Science.gov (United States)

    Manevski, Nenad; Swart, Piet; Balavenkatraman, Kamal Kumar; Bertschi, Barbara; Camenisch, Gian; Kretz, Olivier; Schiller, Hilmar; Walles, Markus; Ling, Barbara; Wettstein, Reto; Schaefer, Dirk J; Itin, Peter; Ashton-Chess, Joanna; Pognan, Francois; Wolf, Armin; Litherland, Karine

    2015-01-01

    Although skin is the largest organ of the human body, cutaneous drug metabolism is often overlooked, and existing experimental models are insufficiently validated. This proof-of-concept study investigated phase II biotransformation of 11 test substrates in fresh full-thickness human skin explants, a model containing all skin cell types. Results show that skin explants have significant capacity for glucuronidation, sulfation, N-acetylation, catechol methylation, and glutathione conjugation. Novel skin metabolites were identified, including acyl glucuronides of indomethacin and diclofenac, glucuronides of 17β-estradiol, N-acetylprocainamide, and methoxy derivatives of 4-nitrocatechol and 2,3-dihydroxynaphthalene. Measured activities for 10 μM substrate incubations spanned a 1000-fold: from the highest 4.758 pmol·mg skin(-1)·h(-1) for p-toluidine N-acetylation to the lowest 0.006 pmol·mg skin(-1)·h(-1) for 17β-estradiol 17-glucuronidation. Interindividual variability was 1.4- to 13.0-fold, the highest being 4-methylumbelliferone and diclofenac glucuronidation. Reaction rates were generally linear up to 4 hours, although 24-hour incubations enabled detection of metabolites in trace amounts. All reactions were unaffected by the inclusion of cosubstrates, and freezing of the fresh skin led to loss of glucuronidation activity. The predicted whole-skin intrinsic metabolic clearances were significantly lower compared with corresponding whole-liver intrinsic clearances, suggesting a relatively limited contribution of the skin to the body's total systemic phase II enzyme-mediated metabolic clearance. Nevertheless, the fresh full-thickness skin explants represent a suitable model to study cutaneous phase II metabolism not only in drug elimination but also in toxicity, as formation of acyl glucuronides and sulfate conjugates could play a role in skin adverse reactions.

  17. Characterization of the chemical reactivity and nephrotoxicity of N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine sulfoxide, a potential reactive metabolite of trichloroethylene.

    Science.gov (United States)

    Irving, Roy M; Pinkerton, Marie E; Elfarra, Adnan A

    2013-02-15

    N-Acetyl-S-(1,2-dichlorovinyl)-L-cysteine (NA-DCVC) has been detected in the urine of humans exposed to trichloroethylene and its related sulfoxide, N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine sulfoxide (NA-DCVCS), has been detected as hemoglobin adducts in blood of rats dosed with S-(1,2-dichlorovinyl)-L-cysteine (DCVC) or S-(1,2-dichlorovinyl)-L-cysteine sulfoxide (DCVCS). Because the in vivo nephrotoxicity of NA-DCVCS was unknown, in this study, male Sprague-Dawley rats were dosed (i.p.) with 230 μmol/kg b.w. NA-DCVCS or its potential precursors, DCVCS or NA-DCVC. At 24 h post treatment, rats given NA-DCVC or NA-DCVCS exhibited kidney lesions and effects on renal function distinct from those caused by DCVCS. NA-DCVC and NA-DCVCS primarily affected the cortico-medullary proximal tubules (S(2)-S(3) segments) while DCVCS primarily affected the outer cortical proximal tubules (S(1)-S(2) segments). When NA-DCVCS or DCVCS was incubated with GSH in phosphate buffer pH 7.4 at 37°C, the corresponding glutathione conjugates were detected, but NA-DCVC was not reactive with GSH. Because NA-DCVCS exhibited a longer half-life than DCVCS and addition of rat liver cytosol enhanced GSH conjugate formation, catalysis of GSH conjugate formation by the liver could explain the lower toxicity of NA-DCVCS in comparison with DCVCS. Collectively, these results provide clear evidence that NA-DCVCS formation could play a significant role in DCVC, NA-DCVC, and trichloroethylene nephrotoxicity. They also suggest a role for hepatic metabolism in the mechanism of NA-DCVC nephrotoxicity.

  18. Hibiscus cannabinus feruloyl-coa:monolignol transferase

    Energy Technology Data Exchange (ETDEWEB)

    Wilkerson, Curtis; Ralph, John; Withers, Saunia; Mansfield, Shawn D.

    2016-11-15

    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.

  19. Feruloyl-CoA:monolignol transferase

    Energy Technology Data Exchange (ETDEWEB)

    Wilkerson, Curtis; Ralph, John; Withers, Saunia; Mansfield, Shawn D.

    2016-09-13

    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.

  20. Feruloyl-CoA:monolignol transferase

    Energy Technology Data Exchange (ETDEWEB)

    Wilkerson, Curtis; Ralph, John; Withers, Saunia; Mansfield, Shawn D.

    2016-11-08

    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.

  1. Indirect flow injection determination of N-acetyl-L-cysteine using cerium(IV) and ferroin; Determinacao indireta de N-acetil-L-cisteina por injecao em fluxo empregando Ce(IV) e ferroina

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Heberth Juliano; Fatibello-Filho, Orlando [Sao Carlos Univ., SP (Brazil). Dept. de Quimica]. E-mail: bello@dq.ufscar.br

    2005-09-15

    An indirect flow injection spectrophotometric procedure is proposed for the determination of N-acetyl-L-cysteine in pharmaceutical formulations. In this system, ferroin ([Fe(II)-(fen){sub 2}]{sup 2+}) in excess, with a strong absorption at 500 nm, is oxidized by cerium(IV) yielding cerium(III) and [Fe(III)-(fen){sub 2}]{sup 3+} (colorless), thus producing a baseline. When N-acetyl-L-cysteine solution is introduced into the flow injection system, it reacts with cerium(IV) increasing the analytical signal in proportion to the drug concentration. Under optimal experimental conditions, the linearity of the analytical curve for N-acetyl-L-cysteine ranged from 6.5x10{sup -6} to 1.3x10{sup -4} mol L{sup -1}. The detection limit was 5.0x10{sup -6} mol L{sup -1}and recoveries between 98.0 and 106% were obtained. The sampling frequency was 60 determinations per hour and the RSD was smaller than 1.4% for 2.2x10{sup -5} mol L{sup -1} N-acetyl-L-cysteine. (author)

  2. Glutathione transferases: a structural perspective.

    Science.gov (United States)

    Oakley, Aaron

    2011-05-01

    The glutathione transferases (GSTs) are one of the most important families of detoxifying enzymes in nature. The classic activity of the GSTs is conjugation of compounds with electrophilic centers to the tripeptide glutathione (GSH), but many other activities are now associated with GSTs, including steroid and leukotriene biosynthesis, peroxide degradation, double-bond cis-trans isomerization, dehydroascorbate reduction, Michael addition, and noncatalytic "ligandin" activity (ligand binding and transport). Since the first GST structure was determined in 1991, there has been an explosion in structural data across GSTs of all three families: the cytosolic GSTs, the mitochondrial GSTs, and the membrane-associated proteins in eicosanoid and glutathione metabolism (MAPEG family). In this review, the major insights into GST structure and function will be discussed.

  3. The tep1 gene of Sinorhizobium meliloti coding for a putative transmembrane efflux protein and N-acetyl glucosamine affect nod gene expression and nodulation of alfalfa plants

    Directory of Open Access Journals (Sweden)

    Soto María

    2009-01-01

    Full Text Available Abstract Background Soil bacteria collectively known as Rhizobium, characterized by their ability to establish beneficial symbiosis with legumes, share several common characteristics with pathogenic bacteria when infecting the host plant. Recently, it was demonstrated that a fadD mutant of Sinorhizobium meliloti is altered in the control of swarming, a type of co-ordinated movement previously associated with pathogenicity, and is also impaired in nodulation efficiency on alfalfa roots. In the phytopathogen Xanthomonas campestris, a fadD homolog (rpfB forms part of a cluster of genes involved in the regulation of pathogenicity factors. In this work, we have investigated the role in swarming and symbiosis of SMc02161, a S. meliloti fadD-linked gene. Results The SMc02161 locus in S. meliloti shows similarities with members of the Major Facilitator Superfamily (MFS of transporters. A S. meliloti null-mutant shows increased sensitivity to chloramphenicol. This indication led us to rename the locus tep1 for transmembrane efflux protein. The lack of tep1 does not affect the appearance of swarming motility. Interestingly, nodule formation efficiency on alfalfa plants is improved in the tep1 mutant during the first days of the interaction though nod gene expression is lower than in the wild type strain. Curiously, a nodC mutation or the addition of N-acetyl glucosamine to the wild type strain lead to similar reductions in nod gene expression as in the tep1 mutant. Moreover, aminosugar precursors of Nod factors inhibit nodulation. Conclusion tep1 putatively encodes a transmembrane protein which can confer chloramphenicol resistance in S. meliloti by expelling the antibiotic outside the bacteria. The improved nodulation of alfalfa but reduced nod gene expression observed in the tep1 mutant suggests that Tep1 transports compounds which influence nodulation. In contrast to Bradyrhizobium japonicum, we show that in S. meliloti there is no feedback regulation

  4. Amelioration of acute sequelae of blast induced mild traumatic brain injury by N-acetyl cysteine: a double-blind, placebo controlled study.

    Directory of Open Access Journals (Sweden)

    Michael E Hoffer

    Full Text Available BACKGROUND: Mild traumatic brain injury (mTBI secondary to blast exposure is the most common battlefield injury in Southwest Asia. There has been little prospective work in the combat setting to test the efficacy of new countermeasures. The goal of this study was to compare the efficacy of N-acetyl cysteine (NAC versus placebo on the symptoms associated with blast exposure mTBI in a combat setting. METHODS: This study was a randomized double blind, placebo-controlled study that was conducted on active duty service members at a forward deployed field hospital in Iraq. All symptomatic U.S. service members who were exposed to significant ordnance blast and who met the criteria for mTBI were offered participation in the study and 81 individuals agreed to participate. Individuals underwent a baseline evaluation and then were randomly assigned to receive either N-acetyl cysteine (NAC or placebo for seven days. Each subject was re-evaluated at 3 and 7 days. Outcome measures were the presence of the following sequelae of mTBI: dizziness, hearing loss, headache, memory loss, sleep disturbances, and neurocognitive dysfunction. The resolution of these symptoms seven days after the blast exposure was the main outcome measure in this study. Logistic regression on the outcome of 'no day 7 symptoms' indicated that NAC treatment was significantly better than placebo (OR = 3.6, p = 0.006. Secondary analysis revealed subjects receiving NAC within 24 hours of blast had an 86% chance of symptom resolution with no reported side effects versus 42% for those seen early who received placebo. CONCLUSION: This study, conducted in an active theatre of war, demonstrates that NAC, a safe pharmaceutical countermeasure, has beneficial effects on the severity and resolution of sequelae of blast induced mTBI. This is the first demonstration of an effective short term countermeasure for mTBI. Further work on long term outcomes and the potential use of NAC in civilian m

  5. Amelioration of Acute Sequelae of Blast Induced Mild Traumatic Brain Injury by N-Acetyl Cysteine: A Double-Blind, Placebo Controlled Study

    Science.gov (United States)

    Slade, Martin D.; Tsao, Jack W.; Hoffer, Barry

    2013-01-01

    Background Mild traumatic brain injury (mTBI) secondary to blast exposure is the most common battlefield injury in Southwest Asia. There has been little prospective work in the combat setting to test the efficacy of new countermeasures. The goal of this study was to compare the efficacy of N-acetyl cysteine (NAC) versus placebo on the symptoms associated with blast exposure mTBI in a combat setting. Methods This study was a randomized double blind, placebo-controlled study that was conducted on active duty service members at a forward deployed field hospital in Iraq. All symptomatic U.S. service members who were exposed to significant ordnance blast and who met the criteria for mTBI were offered participation in the study and 81 individuals agreed to participate. Individuals underwent a baseline evaluation and then were randomly assigned to receive either N-acetyl cysteine (NAC) or placebo for seven days. Each subject was re-evaluated at 3 and 7 days. Outcome measures were the presence of the following sequelae of mTBI: dizziness, hearing loss, headache, memory loss, sleep disturbances, and neurocognitive dysfunction. The resolution of these symptoms seven days after the blast exposure was the main outcome measure in this study. Logistic regression on the outcome of ‘no day 7 symptoms’ indicated that NAC treatment was significantly better than placebo (OR = 3.6, p = 0.006). Secondary analysis revealed subjects receiving NAC within 24 hours of blast had an 86% chance of symptom resolution with no reported side effects versus 42% for those seen early who received placebo. Conclusion This study, conducted in an active theatre of war, demonstrates that NAC, a safe pharmaceutical countermeasure, has beneficial effects on the severity and resolution of sequelae of blast induced mTBI. This is the first demonstration of an effective short term countermeasure for mTBI. Further work on long term outcomes and the potential use of NAC in civilian mTBI is warranted

  6. O-GlcNAc-selective-N-acetyl-beta-D-glucosaminidase activity and mRNA expression in muscle is related to glucosamine-induced insulin resistance.

    Science.gov (United States)

    Durán-Reyes, Genoveva; Pascoe-Lira, Dalila; García-Macedo, Rebeca; Medina-Navarro, Rafael; Rosales-Torres, Ana María; Vergara-Onofre, Marcela; Foyo-Niembro, Enrique; Gutiérrez-Rodríguez, Margarita Eugenia; García-Gutiérrez, María Trinidad Adriana; Valladares-Salgado, Adán; Kumate, Jesús; Cruz, Miguel

    2010-01-01

    Glucosamine (GlcN)-induced insulin resistance is associated with an increase in O-linked-N-acetylglucosaminylated modified proteins (O-GlcNAcylated proteins). The role played by O-GlcNAc-selective-N-acetyl-beta-D-glucosaminidase (O-GlcNAcase), which removes O-N-acetyl-glucosamine residues from O-GlcNAcylated proteins, has not yet been demonstrated. We investigated whether GlcN-induced whole-body insulin resistance is related to tissue O-GlcNAcase activity and mRNA expression. GlcN (30 mumol/kg/min) or physiological saline (control) was intravenously infused into Sprague-Dawley rats for 2 h. After GlcN treatment, rats were subjected to the following: intravenous glucose tolerance test, insulin tolerance test or removal of the liver, muscle and pancreas. GlcN was found to provoke hyperglycemia compared to control (8.6 +/- 0.41 vs. 4.82 +/- 0.17 mM, p < 0.001). The insulin resistance index (HOMA-IR) increased (15.76 +/- 1.47 vs. 10.14 +/- 1.41, p < 0.001) and the beta-cell function index (HOMA-beta) diminished (182.69 +/- 22.37 vs. 592.01 +/- 103, p < 0.001). Liver glucose concentration was higher in the GlcN group than in the control group (0.37 +/- 0.04 vs. 0.24 +/- 0.038 mmol/g dry weight, p < 0.001). Insulin release index (insulin/glucose) was less in the GlcN group than in the control (2.2 +/- 0.1 vs. 8 +/- 0.8 at 120 min, p < 0.001). In the GlcN group, muscle O-GlcNAcase activity diminished (0.28 +/- 0.019 vs. 0.36 +/- 0.018 nmol of p-nitrophenyl/mg protein/min, p < 0.001), and K(m) increased (1.51 +/- 0.11 vs. 1.12 +/- 0.1 mM, p < 0.001) compared to the control. In the GlcN group, O-GlcNAcase activity/mRNA expression was altered (0.6 +/- 0.07 vs. 1 +/- 0.09 of control, p < 0.05). In conclusion, O-GlcNAcase activity is posttranslationally inhibited during GlcN-induced insulin resistance. Copyright (c) 2010 S. Karger AG, Basel.

  7. The tep1 gene of Sinorhizobium meliloti coding for a putative transmembrane efflux protein and N-acetyl glucosamine affect nod gene expression and nodulation of alfalfa plants.

    Science.gov (United States)

    van Dillewijn, Pieter; Sanjuán, Juan; Olivares, José; Soto, María José

    2009-01-27

    Soil bacteria collectively known as Rhizobium, characterized by their ability to establish beneficial symbiosis with legumes, share several common characteristics with pathogenic bacteria when infecting the host plant. Recently, it was demonstrated that a fadD mutant of Sinorhizobium meliloti is altered in the control of swarming, a type of co-ordinated movement previously associated with pathogenicity, and is also impaired in nodulation efficiency on alfalfa roots. In the phytopathogen Xanthomonas campestris, a fadD homolog (rpfB) forms part of a cluster of genes involved in the regulation of pathogenicity factors. In this work, we have investigated the role in swarming and symbiosis of SMc02161, a S. meliloti fadD-linked gene. The SMc02161 locus in S. meliloti shows similarities with members of the Major Facilitator Superfamily (MFS) of transporters. A S. meliloti null-mutant shows increased sensitivity to chloramphenicol. This indication led us to rename the locus tep1 for transmembrane efflux protein. The lack of tep1 does not affect the appearance of swarming motility. Interestingly, nodule formation efficiency on alfalfa plants is improved in the tep1 mutant during the first days of the interaction though nod gene expression is lower than in the wild type strain. Curiously, a nodC mutation or the addition of N-acetyl glucosamine to the wild type strain lead to similar reductions in nod gene expression as in the tep1 mutant. Moreover, aminosugar precursors of Nod factors inhibit nodulation. tep1 putatively encodes a transmembrane protein which can confer chloramphenicol resistance in S. meliloti by expelling the antibiotic outside the bacteria. The improved nodulation of alfalfa but reduced nod gene expression observed in the tep1 mutant suggests that Tep1 transports compounds which influence nodulation. In contrast to Bradyrhizobium japonicum, we show that in S. meliloti there is no feedback regulation of nodulation genes. Moreover, the Nod factor precursor

  8. Sigma-class glutathione transferases.

    Science.gov (United States)

    Flanagan, Jack U; Smythe, Mark L

    2011-05-01

    Mammalian cytosolic glutathione transferases (GSTs) can be grouped into seven classes. Of these, the sigma class is also widely distributed in nature, with isoforms found in both vertebrates and invertebrates. It contains examples of proteins that have evolved specialized functions, such as the cephalopod lens S-crystallins, the mammalian hematopoietic prostaglandin D(2) synthase, and the helminth 28-kDa antigen. In mammals, the sigma-class GST has both anti- and proinflammatory functions, depending on the type of immune response, and an immunomodulatory function is also associated with the enzyme from helminth parasites. In the fly, it is associated with a specific detoxication activity toward lipid oxidation products. Mice genetically depleted of the sigma-class GST, or transgenically overexpressing it, have provided insight into the physiological roles of the GST. Inhibitors of the mammalian enzyme developed by structure-based methods are effective in controlling allergic response. This review covers the structure, function, and pharmacology of vertebrate and invertebrate GSTs.

  9. The influences of N-acetyl cysteine (NAC on the cytotoxicity and mechanical properties of Poly-methylmethacrylate (PMMA-based dental resin

    Directory of Open Access Journals (Sweden)

    Yang Jiao

    2015-04-01

    Full Text Available Objectives. This study aimed to investigate the influences of N-acetyl cysteine (NAC on cytotoxicity and mechanical properties of Poly-methylmethacrylate (PMMA dental resins.Methods. Experimental PMMA resin was prepared by incorporating various concentrations of NAC (0, 0.15, 0.3, 0.6 and 0.9 wt.%. MTT assay was performed to investigate viability of human dental pulp cells after exposure to extract of PMMA resin with or without NAC. Cell adhesion on resin specimens was examined with scanning electron microscopy. Degree of conversion was studied with Fourier Transform Infrared Spectroscopy (FTIR. Flexural strength, microhardness and surface roughness was evaluated using a universal testing machine, microhardness tester and optical profilometer, respectively.Results. Incorporation of NAC into PMMA resin significantly reduced its cytotoxicity and enhanced cell adhesion on its surface. NAC induced negative influences on the mechanical and physical properties of PMMA resin in a dose-dependent manner. The degree of conversion for all experimental PMMA resins reached as high as 72% after 24 h of polymerization. All the tested properties were maintained when the concentration of incorporated NAC was 0.15 wt.%.Conclusion. The addition of 0.15 wt.% NAC remarkably improved biocompatibility of PMMA resin without exerting significant negative influence on its mechanical and physical properties.

  10. Enzymic synthesis of 3'-O- and 6'-O-N-acetylglucosaminyl-N-acetyllactosaminide glycosides catalyzed by beta-N-acetyl-D-hexosaminidase from Nocardia orientalis.

    Science.gov (United States)

    Murata, T; Tashiro, A; Itoh, T; Usui, T

    1997-06-06

    beta-N-acetyl-D-hexosaminidase from Nocardia orientalis catalyzed the synthesis of beta-D-GlcNAc-(1 --> 3)-beta-D-Gal-(1 --> 4)-beta-D-GlcNAc-OC6H4NO2-p (1) and beta-D-GlcNAc-(1 --> 6)-beta-D-Gal-(1 --> 4)-beta-D-GlcNAc-OC6H4NO2-p (2) with its isomer beta-D-Gal-(1 --> 4)-[beta-D-GlcNAc-(1 --> 6)]-beta-D-GlcNAc-OC6H4NO2-p (3) through N-acetylglucosaminyl transfer from N-,N'-diacetylchitobiose to p-nitrophenyl beta-N-acetyllactosaminide. The enzyme formed a mixture of trisaccharides 1, 2, and 3 in a ratio of 11:33:56. In the case, when an inclusion complex of p-nitrophenyl beta-N-acetyllactosaminide with alpha-CD was used, compounds 1, 2, and 3 were formed in a molar ratio of 24:63:13. The regioselectivity of glycosidase-catalyzed formation of the trisaccharide glycosides was substantially changed. It resulted not only in a significant increase of the proportion of the desired compounds 1 and 2 but also in the substantial increase of the overall yield of transfer products.

  11. Comparison of the effects of N-acetyl-cysteine and ginseng in prevention of noise induced hearing loss in male textile workers.

    Science.gov (United States)

    Doosti, Afsaneh; Lotfi, Yones; Moossavi, Abdollah; Bakhshi, Enayatollah; Talasaz, Azita Hajhossein; Hoorzad, Ahmad

    2014-01-01

    Previous studies revealed the role of antioxidant agents in prevention of noise induced hearing loss (NIHL). The aim of this study was to compare the protective effect of N-acetyl-cysteine (NAC) and ginseng on protection of NIHL in textile workers exposed to continuous noise in daily working. In this study, 48 participants were randomly allocated to three groups; Group I received NAC 1200 mg/day, Group II received ginseng 200 mg/day, and Group III (control group) received no supplement. Pure tone audiometry and high frequency audiometry were performed preshift before and after 14 days (on day 15). Linear regression analysis results showed reduced noise-induced temporary threshold shift (TTS) for NAC and ginseng groups at 4, 6 and 16 kHz (P < 0.001) in both ears. Furthermore, the protective effects were more prominent in NAC than ginseng. Our results show that NAC and ginseng can reduce noise induced TTS in workers exposed to occupational noise. Further studies are needed to prove antioxidants benefits in hearing conservation programs.

  12. L-lactate dehydrogenase and N-acetyl-beta-D-glucosaminidase activities in bovine milk as indicators of non-specific mastitis.

    Science.gov (United States)

    Chagunda, Mizeck Gg; Larsen, Torben; Bjerring, Martin; Ingvartsen, Klaus L

    2006-11-01

    Systematic factors affecting the activities of L-lactate dehydrogenase (LDH) and N-acetyl-beta-D-glucosaminidase (NAGase) and somatic cell count (SCC), the association between the activities of LDH and NAGase and SCC with respect to udder health status, and the ability of LDH and NAGase to classify cows in udder health categories for early detection of mastitis were studied. A dataset of records from 74 Danish Holstein, 76 Danish Red and 47 Jersey cows on one research farm was used. Cows were grouped into healthy and clinically mastitic. A healthy cow was defined as having no veterinary treatment and SCCmastitis and SCC >800,000 cells/ml. Breed, month of production, and days in milk significantly influenced (Pmastitis. NAGase activity had numerically higher variation in healthy cows than in clinically mastitic cows (CV=56.2% v. CV=53.5%). The relationship between LDH activity and SCC was stronger in milk from clinically mastitic than from healthy cows (r=0.76 v. r=0.48 and r=0.67 v. r=0.44 for correlation of observed values and residuals, respectively). LDH activity had higher sensitivity than NAGase activity (73-95% v. 35-77%) while specificities were in a similar range (92-99%). Further, sensitivities for LDH activity were more robust to changes in the threshold value than those for NAGase activity. Opportunities for automated, in-line real-time mastitis detection are discussed.

  13. A cross-reacting human idiotype (B17) associated with antibodies to N-acetyl-D-glucosamine. Specificity, immunoglobulin class association, and distribution in the population.

    Science.gov (United States)

    Emmrich, F; Greger, B; Eichmann, K

    1983-04-01

    This report describes the study of the expression of an idiotype in the human population which is associated with antibodies to N-acetyl-D-glucosamine (GlcNAc) present in most human sera presumably due to streptococcal infections. The idiotype is identified with antisera and monoclonal antibodies prepared against the IgM (kappa) antibody secreted by the Epstein-Barr virus-transformed human B cell line B17. At least 90% of 207 individuals tested had immunoglobulin with B17 idiotypic determinants in their sera, as demonstrated with conventional and one monoclonal anti-idiotypic antibody. Another monoclonal anti-idiotypic antibody reacted with antibodies in only a few of the sera. No correlation was found between the level of expression of different idiotopes in individual human sera, suggesting molecular heterogeneity of the B17-positive antibody population. B17-positive immunoglobulins are to a large extent specific for GlcNAc but represent only a minor population of all GlcNAc-specific antibodies in human sera. B17 determinants are on IgM (kappa) in all human sera and on IgG and IgA in some. In addition, some lambda-bearing Ig was found to react with anti-B17 antisera, suggesting the detection of VH-associated idiotypic determinants in this experimental system.

  14. N-Acetyl Cysteine Depletes Reactive Oxygen Species and Prevents Dental Monomer-Induced Intrinsic Mitochondrial Apoptosis In Vitro in Human Dental Pulp Cells.

    Directory of Open Access Journals (Sweden)

    Yang Jiao

    Full Text Available To investigate the involvement of intrinsic mitochondrial apoptosis in dental monomer-induced cytotoxicity and the influences of N-acetyl cysteine (NAC on this process.Human dental pulp cells (hDPCs were exposed to several dental monomers in the absence or presence of NAC, and cell viability, intracellular redox balance, morphology and function of mitochondria and key indicators of intrinsic mitochondrial apoptosis were evaluated using various commercial kits.Dental monomers exerted dose-dependent cytotoxic effects on hDPCs. Concomitant to the over-production of reactive oxygen species (ROS and depletion of glutathione (GSH, differential changes in activities of superoxide dismutase, glutathione peroxidase, and catalase were detected. Apoptosis, as indicated by positive Annexin V/propidium iodide (PI staining and activation of caspase-3, was observed after dental monomer treatment. Dental monomers impaired the morphology and function of mitochondria, and induced intrinsic mitochondrial apoptosis in hDPCs via up-regulation of p53, Bax and cleaved caspase-3, and down-regulation of Bcl-2. NAC restored cell viability, relieved oxidative stress and blocked the apoptotic effects of dental monomers.Dental monomers induced oxidative stress and mitochondrial intrinsic apoptosis in hDPCs. NAC could reduce the oxidative stress and thus protect hDPCs against dental monomer-induced apoptosis.

  15. Hydrothermal conversion of N-acetyl-d-glucosamine to 5-hydroxymethylfurfural using ionic liquid as a recycled catalyst in a water-dimethyl sulfoxide mixture.

    Science.gov (United States)

    Zang, Hongjun; Yu, Songbai; Yu, Pengfei; Ding, Hongying; Du, Yannan; Yang, Yuchan; Zhang, Yiwen

    2017-04-10

    Here, N-acetyl-d-glucosamine (GlcNAc), the monomer composing the second most abundant biopolymer, chitin, was efficiently converted into 5-hydroxymethylfurfural (5-HMF) using ionic liquid (IL) catalysts in a water/dimethyl sulfoxide (DMSO) mixture solvent. Various reaction parameters, including reaction temperature and time, DMSO/water mass ratios and catalyst dosage were optimized. A series of ILs with different structures were analyzed to explore their impact on GlcNAc conversion. The substrate scope was expanded from GlcNAc to d-glucosamine, chitin, chitosan and monosaccharides, although 5-HMF yields obtained from polymers and other monosaccharides were generally lower than those from GlcNAc. Moreover, the IL N-methylimidazolium hydrogen sulfate ([Hmim][HSO4]) exhibited the best catalyst performance (64.6% yield) when GlcNAc was dehydrated in a DMSO/water mixture at 180 °C for 6 h without the addition of extra catalysts. To summarize, these results could provide knowledge essential to the production of valuable chemicals that are derived from renewable marine resources and benefit biofuel-related applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Molecular cloning and characterization of a cDNA encoding the N-acetyl-beta-D-glucosaminidase homologue of Paracoccidioides brasiliensis.

    Science.gov (United States)

    Santos, Mônica O; Pereira, Maristela; Felipe, Maria Sueli S; Jesuino, Rosalia Santos A; Ulhoa, Cirano J; Soares, Renata de Bastos A; Soares, Celia Maria de A

    2004-06-01

    A cDNA encoding the N-acetyl-beta-D-glucosaminidase (NAG) protein of Paracoccidioides brasiliensis, Pb NAG1, was cloned and characterized. The 2663-nucleotide sequence of the cDNA consisted of a single open reading frame encoding a protein with a predicted molecular mass of 64.73 kDa and an isoeletric point of 6.35. The predicted protein includes a putative 30-amino-acid signal peptide. The protein as a whole shares considerable sequence similarity with 'classic' NAG. The primary sequence of Pb NAG1 was used to infer phylogenetic relationships. The amino acid sequence of Pb NAG1 has 45, 31 and 30% identity, respectively, with homologous sequences from Trichoderma harzianum, Aspergillus nidulans and Candida albicans. In particular, striking homology was observed with the active site regions of the glycosyl hydrolase group of proteins (family 20). The expected active site consensus motif G X D E and catalytic Asp and Glu residues at positions 373 and 374 were found, reinforcing that Pb NAG1 belongs to glycosyl hydrolase family 20. The nucleotide sequence of Pb nag1 and its flanking regions have been deposited, along with the amino acid sequence of the deduced protein, in GenBank under accession number AF419158.

  17. The acetaminophen metabolite N-acetyl-p-benzoquinone imine (NAPQI) inhibits glutathione synthetase in vitro; a clue to the mechanism of 5-oxoprolinuric acidosis?

    Science.gov (United States)

    Walker, Valerie; Mills, Graham A; Anderson, Mary E; Ingle, Brandall L; Jackson, John M; Moss, Charlotte L; Sharrod-Cole, Hayley; Skipp, Paul J

    2017-02-01

    1. Metabolic acidosis due to accumulation of l-5-oxoproline is a rare, poorly understood, disorder associated with acetaminophen treatment in malnourished patients with chronic morbidity. l-5-Oxoprolinuria signals abnormal functioning of the γ-glutamyl cycle, which recycles and synthesises glutathione. Inhibition of glutathione synthetase (GS) by N-acetyl-p-benzoquinone imine (NAPQI) could contribute to 5-oxoprolinuric acidosis in such patients. We investigated the interaction of NAPQI with GS in vitro. 2. Peptide mapping of co-incubated NAPQI and GS using mass spectrometry demonstrated binding of NAPQI with cysteine-422 of GS, which is known to be essential for GS activity. Computational docking shows that NAPQI is properly positioned for covalent bonding with cysteine-422 via Michael addition and hence supports adduct formation. 3. Co-incubation of 0.77 μM of GS with NAPQI (25-400 μM) decreased enzyme activity by 16-89%. Inhibition correlated strongly with the concentration of NAPQI and was irreversible. 4. NAPQI binds covalently to GS causing irreversible enzyme inhibition in vitro. This is an important novel biochemical observation. It is the first indication that NAPQI may inhibit glutathione synthesis, which is pivotal in NAPQI detoxification. Further studies are required to investigate its biological significance and its role in 5-oxoprolinuric acidosis.

  18. Synthesis, Crystal Structure and Luminescent Properties of a Novel Zinc(Ⅱ) Complex of N-Acetyl-L-glutamic Acid and Imidazole Ligands

    Institute of Scientific and Technical Information of China (English)

    CHENG Meng-Qi; MA Lu-Fang; WANG Li-Ya; WANG Jian-Ge

    2006-01-01

    A novel complex (Zn(Im)2(A-glu)·0.5H2O (Im = imidazole, A-glu = N-acetyl- L-glutamic acid) has been synthesized from the reaction of A-glu with Zn(CH3COO)2(2H2O in the presence of Im at 65 ℃, and structurally characterized by single-crystal X-ray diffraction. The complex crystallizes in tetragonal, space group P43212 with a = b = 8.9078(6), c = 43.458(6) (A), C26H36N10O11Zn2, Mr = 795.39, V = 3448.3(6) (A)3, Dc = 1.532 g/cm3, Z = 4, μ(MoK() = 1.461 mm(1, F(000) = 1640, the final R = 0.0453 and wR = 0.0992. X-ray analysis reveals that the crystal structure is constructed by mixed ligands. A-glu adopts the bis-monodentate coordination mode linking two adjacent metal ions to form a one-dimensional chain. Zinc(Ⅱ) ions are four-coordinated with a distorted tetrahedral geometry. Luminescent properties of the complex have been inves- tigated.

  19. Effects of N-acetyl-L-cysteine on redox status and markers of renal function in mice inoculated with Bothrops jararaca and Crotalus durissus terrificus venoms.

    Science.gov (United States)

    Barone, Juliana Marton; Frezzatti, Rodrigo; Silveira, Paulo Flavio

    2014-03-01

    Renal dysfunction is an important aggravating factor in accidents caused by Crotalus durissus terrificus (Cdt) and Bothrops jararaca (Bj) bites. N-acetyl-l-cysteine (NAC) is well known as a nephroprotective antioxidant with low toxicity. The present study investigated the effects of NAC on redox status and markers of renal function in mice that received vehicle (controls) or venoms (v) of Cdt and Bj. In controls NAC promoted hypercreatinemia, hypouremia, hyperosmolality with decreased urea in urine, hyperproteinuria, decreased protein and increased dipeptidyl peptidase IV (DPPIV) in membrane-bound fraction (MF) from renal cortex (RC) and medulla (RM). NAC ameliorated or normalized altered creatinuria, proteinemia and aminopeptidase (AP) acid in MF, AP basic (APB) in soluble fraction (SF), and neutral AP in SF and MF from RC and RM in vBj envenomation. NAC ameliorated or normalized altered neutral AP in SF from RC and RM, and DPPIV and protein in MF from RC in vCdt envenomation. NAC ameliorated or restored renal redox status respectively in vCdt and vBj, and normalized uricemia in both envenomations. These data are promising perspectives that recommend the clinical evaluation of NAC as potential coadjuvant in the anti venom serotherapy for accidents with these snake's genera.

  20. Non-classical processes in surface hemostasis: mechanisms for the poly-N-acetyl glucosamine-induced alteration of red blood cell morphology and surface prothrombogenicity

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Thomas H; Smith, Carr J; Scull, Christopher M; Merricks, Elizabeth P; Nichols, Timothy C [Francis Owen Blood Research Laboratory, Department of Pathology and Laboratory Medicine, 125 University Lake Dr., CB 3114, University of North Carolina at Chapel Hill, NC (United States); Valeri, C Robert [Naval Blood Research Laboratory, Inc., Boston, MA (United States); Demcheva, Marina; Vournakis, John N [Marine Polymer Technologies, Inc., Danvers, MA (United States)

    2008-03-01

    It is well established that platelets and the intrinsic plasma coagulation pathway can be activated when blood contacts artificial surfaces. Experiments were performed to assess the effect of hemostatic poly-N-acetyl glucosamine (pGlcNAc) nanofibers on red blood cells. The pGlcNAc nanofibers, isolated from a marine diatom, interact with red blood cells (RBCs) to produce stomatocytes. The stomatocytes could be converted to echinocytes by treatment with echinocytic reagents, as measured by electron microscopy. Electrophoretic and Western blot analysis of RBC surface proteins demonstrated that pGlcNAc fibers were bound to band 3 of the RBC. An important and unique result of the interaction of RBCs with pGlcNAc fibers was the activation of the intrinsic coagulation cascade. This prothrombotic effect was associated with the presentation of phosphatidylserine on the outer layer of the surface membrane of nanofiber bound RBCs. The results demonstrate that RBCs can play a direct and important role in achieving surface hemostasis by accelerating the generation of thrombin, and add to the growing body of evidence that RBCs can strongly interact with hemostatic systems.

  1. The Role of e-NOS in Chronic Cholestasis-Induced Liver and Renal Injury in Rats: The Effect of N-Acetyl Cysteine

    Directory of Open Access Journals (Sweden)

    Yusuf Gunay

    2014-01-01

    Full Text Available Introduction. The role of chronic cholestasis (CC in liver injury and fibrosis remains unclear. The aims of this study were to define the role of endothelial nitric oxide synthase (e-NOS in CC and the protective effect of N-acetyl-L-cysteine (NAC in liver and kidney injury. Materials and Methods. Group A (sham group; Group B (CBDL; and Group C (CBDL + NAC. Group C received daily dosage of NAC (100 mg/kg intraperitoneally for up to 4 weeks. Results. The rate of bridging fibrosis was higher (100% versus 20%, P=.025, but the intensity of e-NOS in liver was lower in rats that received NAC (1.3 versus 2.7, P=.046. The necrotic area in the kidneys among rats that received NAC was lower at week 4 (48% versus 57%; P<.001. The numbers of e-NOS stained cells in kidney were similar in sham group and the two groups with CBDL. Discussion. NAC reduced the stimulus for liver fibrosis in this rat model of CC and attenuated liver and kidney injury. Our study showed that e-NOS expression increased in liver tissue of rats with CC and that this was reversed by NAC. Treatment with NAC might restore e-NOS protein expression and prevent liver injury in CC.

  2. Restoring the impaired cardiac calcium homeostasis and cardiac function in iron overload rats by the combined deferiprone and N-acetyl cysteine

    Science.gov (United States)

    Wongjaikam, Suwakon; Kumfu, Sirinart; Khamseekaew, Juthamas; Chattipakorn, Siriporn C.; Chattipakorn, Nipon

    2017-01-01

    Intracellular calcium [Ca2+]i dysregulation plays an important role in the pathophysiology of iron overload cardiomyopathy. Although either iron chelators or antioxidants provide cardioprotection, a comparison of the efficacy of deferoxamine (DFO), deferiprone (DFP), deferasirox (DFX), N-acetyl cysteine (NAC) or a combination of DFP plus NAC on cardiac [Ca2+]i homeostasis in chronic iron overload has never been investigated. Male Wistar rats were fed with either a normal diet or a high iron (HFe) diet for 4 months. At 2 months, HFe rats were divided into 6 groups and treated with either a vehicle, DFO (25 mg/kg/day), DFP (75 mg/kg/day), DFX (20 mg/kg/day), NAC (100 mg/kg/day), or combined DFP plus NAC. At 4 months, the number of cardiac T-type calcium channels was increased, whereas cardiac sarcoplasmic-endoplasmic reticulum Ca2+ ATPase (SERCA) was decreased, leading to cardiac iron overload and impaired cardiac [Ca2+]i homeostasis. All pharmacological interventions restored SERCA levels. Although DFO, DFP, DFX or NAC alone shared similar efficacy in improving cardiac [Ca2+]i homeostasis, only DFP + NAC restored cardiac [Ca2+]i homeostasis, leading to restoring left ventricular function in the HFe-fed rats. Thus, the combined DFP + NAC was more effective than any monotherapy in restoring cardiac [Ca2+]i homeostasis, leading to restored myocardial contractility in iron-overloaded rats. PMID:28287621

  3. Mitochondrial protein adducts formation and mitochondrial dysfunction during N-acetyl-m-aminophenol (AMAP)-induced hepatotoxicity in primary human hepatocytes

    Science.gov (United States)

    Xie, Yuchao; McGill, Mitchell R.; Du, Kuo; Dorko, Kenneth; Kumer, Sean C.; Schmitt, Timothy M.; Ding, Wen-Xing; Jaeschke, Hartmut

    2015-01-01

    3′-Hydroxyacetanilide or N-acetyl-meta-aminophenol (AMAP) is generally regarded as a non-hepatotoxic analog of acetaminophen (APAP). Previous studies demonstrated absence of toxicity after AMAP in mice, hamsters, primary mouse hepatocytes and several cell lines. In contrast, experiments with liver slices suggested that it may be toxic to human hepatocytes; however, the mechanism of toxicity is unclear. To explore this, we treated primary human hepatocytes (PHH) with AMAP or APAP for up to 48 h and measured several parameters to assess metabolism and injury. Although less toxic than APAP, AMAP dose-dependently triggered cell death in PHH as indicated by alanine aminotransferase (ALT) release and propidium iodide (PI) staining. Similar to APAP, AMAP also significantly depleted glutathione (GSH) in PHH and caused mitochondrial damage as indicated by glutamate dehydrogenase (GDH) release and the JC-1 assay. However, unlike APAP, AMAP treatment did not cause relevant c-jun-N-terminal kinase (JNK) activation in the cytosol or phospho-JNK translocation to mitochondria. To compare, AMAP toxicity was assessed in primary mouse hepatocytes (PMH). No cytotoxicity was observed as indicated by the lack of lactate dehydrogenase release and no PI staining. Furthermore, there was no GSH depletion or mitochondrial dysfunction after AMAP treatment in PMH. Immunoblotting for arylated proteins suggested that AMAP treatment caused extensive mitochondrial protein adducts formation in PHH but not in PMH. In conclusion, AMAP is hepatotoxic in PHH and the mechanism involves formation of mitochondrial protein adducts and mitochondrial dysfunction. PMID:26431796

  4. Fenton reaction-mediated fluorescence quenching of N-acetyl-L-cysteine-protected gold nanoclusters: analytical applications of hydrogen peroxide, glucose, and catalase detection.

    Science.gov (United States)

    Deng, Hao-Hua; Wu, Gang-Wei; He, Dong; Peng, Hua-Ping; Liu, Ai-Lin; Xia, Xing-Hua; Chen, Wei

    2015-11-21

    Given the importance of hydrogen peroxide (H2O2) in many biological processes and its wide application in various industries, the demand for sensitive, accurate, and economical H2O2 sensors is high. In this study, we used Fenton reaction-stimulated fluorescence quenching of N-acetyl-L-cysteine-protected gold nanoclusters (NAC-AuNCs) as a reporter system for the determination of H2O2. After the experimental conditions were optimized, the sensing platform enabled the analysis of H2O2 with a limit of detection (LOD) as low as 0.027 μM. As the glucose oxidase cascade leads to the generation of H2O2 and catalase catalyzes the decomposition of H2O2, these two biocatalytic procedures can be probed by the Fenton reaction-mediated quenching of NAC-AuNCs. The LOD for glucose was found to be 0.18 μM, and the linear range was 0.39-27.22 μM. The LOD for catalase was 0.002 U mL(-1), and the linear range was 0.01-0.3 U mL(-1). Moreover, the proposed sensing methods were successfully applied for human serum glucose detection and the non-invasive determination of catalase activity in human saliva, demonstrating their great potential for practical applications.

  5. The activity of N-acetyl-β-hexosaminidase in boar seminal plasma is linked with semen quality and its suitability for cryopreservation.

    Science.gov (United States)

    Wysocki, Paweł; Orzołek, Aleksandra; Strzeżek, Jerzy; Koziorowska-Gilun, Magdalena; Zasiadczyk, Łukasz; Kordan, Władysław

    2015-04-15

    The determination of sperm cryotolerance is an important step in the process of developing optimal techniques for the storage of boar semen. The objective of this study was to determine individual proteome variations in boar seminal plasma and spermatozoa and establish their influence on the cryotolerance of ejaculate. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed the presence of protein with estimated molecular weight of 90 kDa in sperm extracts from ejaculates of selected boars. In all cases, dialysis performed at the initial stage of cryopreservation effectively removed the protein from sperm cells. The protein had an affinity for Zn(2+) ions. Mass spectrometry revealed similarities between the discussed protein and the β subunit of N-acetyl-β-hexosaminidase (β-HEX). Seminal plasma β-HEX was purified 252-fold with approximately 27% recovery and specific activity of 1800 U/mg of protein. Enzyme activity in fresh seminal plasma was correlated with superoxide dismutase activity (r = -0.42, P 20,000 U/L) levels of β-HEX activity in seminal plasma. In plasma with high β-HEX activity, spermatozoa were characterized by lower plasma membrane integrity (84.7%, P spermatozoa/h) were reported in ejaculates with high seminal plasma β-HEX activity. The results of this study indicate that β-HEX activity in seminal plasma is a useful indicator in preliminary evaluations of boar sperm cryotolerance.

  6. Oral Administration of N-Acetyl-seryl-aspartyl-lysyl-proline Ameliorates Kidney Disease in Both Type 1 and Type 2 Diabetic Mice via a Therapeutic Regimen.

    Science.gov (United States)

    Nitta, Kyoko; Shi, Sen; Nagai, Takako; Kanasaki, Megumi; Kitada, Munehiro; Srivastava, Swayam Prakash; Haneda, Masakazu; Kanasaki, Keizo; Koya, Daisuke

    2016-01-01

    Kidney fibrosis is the final common pathway of progressive kidney diseases including diabetic nephropathy. Here, we report that the endogenous antifibrotic peptide N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP), the substrate of angiotensin-converting enzyme (ACE), is an orally available peptide drug used to cure kidney fibrosis in diabetic mice. We utilized two mouse models of diabetic nephropathy, streptozotocin- (STZ-) induced type 1 diabetic CD-1 mice and type 2 diabetic nephropathy model db/db mice. Intervention with the ACE inhibitor imidapril, oral AcSDKP, or imidapril + oral AcSDKP combination therapy increased urine AcSDKP levels. AcSDKP levels were significantly higher in the combination group compared to those of the other groups. AcSDKP oral administration, either AcSDKP alone or in addition to imidapril, ameliorated glomerulosclerosis and tubulointerstitial fibrosis. Plasma cystatin C levels were higher in both models, at euthanasia, and were restored by all the treatment groups. The levels of antifibrotic miRs, such as miR-29 or let-7, were suppressed in the kidneys of both models; all treatments, especially the combination of imidapril + oral AcSDKP, restored the antifibrotic miR levels to a normal value or even higher. AcSDKP may be an oral antifibrotic peptide drug that would be relevant to combating fibroproliferative kidney diseases such as diabetic nephropathy.

  7. Effect of vasoactive intestinal peptide and naloxone combination on urinary N-acetyl-beta-D-glucosaminidase level and kidney histology of rats exposed to severe hemorrhage.

    Science.gov (United States)

    Akin, M Z; Tunçel, N; Gürer, F; Kural, N; Uslu, S

    1993-09-01

    Renal hypoperfusion which occurs in hemorrhagic shock creates an environment in which cellular injury and organ dysfunction can occur during the episode of shock as well as reoxygenation and reperfusion. At the same time, mast cell degranulation which is observed during hemorrhage may have an additional deleterious effect on the kidney. Twenty-two (Mus norvegicus albinos) rats (200-250 g) of either sex were used. The animals were divided into three groups. Group 1, the control group, was exposed to a 40% hemorrhage. Group 2 was exposed to 40% hemorrhage and then shed blood reperfused. Group 3 was exposed to 40% hemorrhage, and in addition to shed blood reperfusion 25 ng kg-1 vasoactive intestinal peptide (VIP) + 5 mg kg-1 naloxone (NLX) were given. At the end of the experiment the kidneys were evaluated either histologically or by measurement of the urinary N-acetyl-beta-D-glucosaminidase (NAG) activity. Shed blood reperfusion caused continuation of ischemic tissue damage and elevation of urinary NAG activity. Addition of VIP and NLX to the blood reperfusion caused a decrease in urinary NAG excretion, and the histology of renal tissue was almost normal.

  8. The Amelioration of N-Acetyl-p-Benzoquinone Imine Toxicity by Ginsenoside Rg3: The Role of Nrf2-Mediated Detoxification and Mrp1/Mrp3 Transports

    Directory of Open Access Journals (Sweden)

    Sang Il Gum

    2013-01-01

    Full Text Available Previously, we found that Korean red ginseng suppressed acetaminophen (APAP-induced hepatotoxicity via alteration of its metabolic profile involving GSTA2 induction and that ginsenoside Rg3 was a major component of this gene induction. In the present study, therefore, we assessed the protective effect of Rg3 against N-acetyl-p-benzoquinone imine (NAPQI, a toxic metabolic intermediate of APAP. Excess NAPQI resulted in GSH depletion with increases in the ALT and AST activities in H4IIE cells. Rg3 pretreatment reversed GSH depletion by NAPQI. Rg3 resulted in increased mRNA levels of the catalytic and modulatory subunit of glutamate cysteine ligase (GCL, the rate-limiting steps in GSH synthesis and subsequently increased GSH content. Rg3 increased levels of nuclear Nrf2, an essential transcriptional factor of these genes. The knockdown or knockout of the Nrf2 gene abrogated the inductions of mRNA and protein by Rg3. Abolishment of the reversal of GSH depletion by Rg3 against NAPQI was observed in Nrf2-deficient cells. Rg3 induced multidrug resistance-associated protein (Mrp 1 and Mrp3 mRNA levels, but not in Nrf2-deficient cells. Taken together, these results demonstrate that Rg3 is efficacious in protecting hepatocytes against NAPQI insult, due to GSH repletion and coordinated gene regulations of GSH synthesis and Mrp family genes by Nrf2.

  9. Restored viability and function of dental pulp cells on poly-methylmethacrylate (PMMA)-based dental resin supplemented with N-acetyl cysteine (NAC).

    Science.gov (United States)

    Kojima, N; Yamada, M; Paranjpe, A; Tsukimura, N; Kubo, K; Jewett, A; Ogawa, T

    2008-12-01

    This study examines cytotoxicity of poly-methylmethacrylate (PMMA)-based dental temporary filling resin to dental pulp cells, and the potential amelioration of the toxicity with an anti-oxidant amino-acid, N-acetyl cysteine (NAC). Dental pulp cells extracted from rat maxillary incisors were cultured on the resin material with or without NAC incorporation, or on the polystyrene. The cultures were supplied with osteoblastic media, containing dexamethasone. Forty five percent of cells on the PMMA dental resin were necrotic at 24h after seeding. However, this percentage was reduced to 27% by incorporating NAC in the resin, which was the level equivalent to that in the culture on polystyrene. The culture on the untreated resin was found to be negative for alkaline phosphate (ALP) activity at days 5 and 10 or von Kossa mineralized nodule formation at day 20. In contrast, some areas of the cultures on NAC-incorporated resin substrates were ALP and von Kossa positive. Collagen I and dentin sialoprotein genes were barely expressed in day 7 culture on the untreated resin. However, those genes were expressed in the culture on the resin with NAC. These results suggest that the decreased cell viability and the nearly completely suppressed odontoblast-like cell phenotype of dental pulp cells cultured on PMMA dental resin can be salvaged to a biologically significant degree by the incorporation of NAC in the resin.

  10. The influences of N-acetyl cysteine (NAC) on the cytotoxicity and mechanical properties of Poly-methylmethacrylate (PMMA)-based dental resin.

    Science.gov (United States)

    Jiao, Yang; Ma, Sai; Li, Jing; Shan, Lequn; Yang, Yanwei; Li, Meng; Chen, Jihua

    2015-01-01

    Objectives. This study aimed to investigate the influences of N-acetyl cysteine (NAC) on cytotoxicity and mechanical properties of Poly-methylmethacrylate (PMMA) dental resins. Methods. Experimental PMMA resin was prepared by incorporating various concentrations of NAC (0, 0.15, 0.3, 0.6 and 0.9 wt.%). MTT assay was performed to investigate viability of human dental pulp cells after exposure to extract of PMMA resin with or without NAC. Cell adhesion on resin specimens was examined with scanning electron microscopy. Degree of conversion was studied with Fourier Transform Infrared Spectroscopy (FTIR). Flexural strength, microhardness and surface roughness was evaluated using a universal testing machine, microhardness tester and optical profilometer, respectively. Results. Incorporation of NAC into PMMA resin significantly reduced its cytotoxicity and enhanced cell adhesion on its surface. NAC induced negative influences on the mechanical and physical properties of PMMA resin in a dose-dependent manner. The degree of conversion for all experimental PMMA resins reached as high as 72% after 24 h of polymerization. All the tested properties were maintained when the concentration of incorporated NAC was 0.15 wt.%. Conclusion. The addition of 0.15 wt.% NAC remarkably improved biocompatibility of PMMA resin without exerting significant negative influence on its mechanical and physical properties.

  11. Reengineering of the feedback-inhibition enzyme N-acetyl-L-glutamate kinase to enhance L-arginine production in Corynebacterium crenatum.

    Science.gov (United States)

    Zhang, Jingjing; Xu, Meijuan; Ge, Xiaoxun; Zhang, Xian; Yang, Taowei; Xu, Zhenghong; Rao, Zhiming

    2017-02-01

    N-acetyl-L-glutamate kinase (NAGK) catalyzes the second step of L-arginine biosynthesis and is inhibited by L-arginine in Corynebacterium crenatum. To ascertain the basis for the arginine sensitivity of CcNAGK, residue E19 which located at the entrance of the Arginine-ring was subjected to site-saturated mutagenesis and we successfully illustrated the inhibition-resistant mechanism. Typically, the E19Y mutant displayed the greatest deregulation of L-arginine feedback inhibition. An equally important strategy is to improve the catalytic activity and thermostability of CcNAGK. For further strain improvement, we used site-directed mutagenesis to identify mutations that improve CcNAGK. Results identified variants I74V, F91H and K234T display higher specific activity and thermostability. The L-arginine yield and productivity of the recombinant strain C. crenatum SYPA-EH3 (which possesses a combination of all four mutant sites, E19Y/I74V/F91H/K234T) reached 61.2 and 0.638 g/L/h, respectively, after 96 h in 5 L bioreactor fermentation, an increase of approximately 41.8% compared with the initial strain.

  12. Biomedical Activity of Chitin/Chitosan Based Materials—Influence of Physicochemical Properties Apart from Molecular Weight and Degree of N-Acetylation

    Directory of Open Access Journals (Sweden)

    Mirko X. Weinhold

    2011-11-01

    Full Text Available The physicochemical nature of chitin and chitosan, which influences the biomedical activity of these compounds, is strongly related to the source of chitin and the conditions of the chitin/chitosan production process. Apart from widely described key factors such as weight-averaged molecular weight (MW and degree of N-acetylation (DA, other physicochemical parameters like polydispersity (MW/MN, crystallinity or the pattern of acetylation (PA have to be taken into consideration. From the biological point of view, these parameters affect a very important factor—the solubility of chitin and chitosan in water and organic solvents. The physicochemical properties of chitosan solutions can be controlled by manipulating solution conditions (temperature, pH, ionic strength, concentration, solvent. The degree of substitution of the hydroxyl and the amino groups or the degree of quaternization of the amino groups also influence the mechanical and biological properties of chitosan samples. Finally, a considerable research effort has been directed towards developing safe and efficient chitin/chitosan-based products because many factors, like the size of nanoparticles, can determine the biomedical characteristics of medicinal products. The influence of these factors on the biomedical activity of chitin/chitosan-based products is presented in this report in more detail.

  13. Early increase in marker of neuronal integrity with antidepressant treatment of major depression: 1H-magnetic resonance spectroscopy of N-acetyl-aspartate.

    Science.gov (United States)

    Taylor, Matthew J; Godlewska, Beata R; Norbury, Ray; Selvaraj, Sudhakar; Near, Jamie; Cowen, Philip J

    2012-11-01

    Increasing interest surrounds potential neuroprotective or neurotrophic actions of antidepressants. While growing evidence points to important early clinical and neuropsychological effects of antidepressants, the time-course of any effect on neuronal integrity is unclear. This study used magnetic resonance spectroscopy to assess effects of short-term treatment with escitalopram on N-acetyl-aspartate (NAA), a marker of neuronal integrity. Thirty-nine participants with major depression were randomly assigned to receive either 10 mg escitalopram or placebo daily in a double-blind, parallel group design. On the seventh day of treatment, PRESS data were obtained from a 30×30×20 mm voxel placed in medial frontal cortex. Age and gender-matched healthy controls who received no treatment were also scanned. Levels of NAA were significantly higher in patients treated with escitalopram than in either placebo-treated patients (p<0.01) or healthy controls (p<0.01). Our findings are consistent with the proposition that antidepressant treatment in depressed patients can produce early changes in neuronal integrity.

  14. N-acetyl-L-cysteine increases MnSOD activity and enhances the recruitment of quiescent human fibroblasts to the proliferation cycle during wound healing.

    Science.gov (United States)

    Mao, Gaowei; Goswami, Monali; Kalen, Amanda L; Goswami, Prabhat C; Sarsour, Ehab H

    2016-01-01

    The rebuilding of the connective tissue during wound healing requires the recruitment of fibroblasts to the wound area as well as reentry of quiescent fibroblasts to the proliferative cycle. Whether this process can be modulated by a small molecular weight thiol antioxidant N-acetyl-L-cysteine (NAC) was tested in normal human skin fibroblasts (NHFs) using a uni-directional wound healing assay. NAC treated cells demonstrated a decreased migration rate but increased number of proliferating cells recruited into the wound area post wounding. Fifteen day quiescent control and NAC treated NHFs were re-plated at a lower density and cell numbers counted at different days post-plating. Interestingly, NAC treated cells exhibited increased cellular proliferation indicated by both decreased cell population doubling time and increased S phase cells. NAC treated cells demonstrated decreased steady state levels of reactive oxygen species as well as increased protein and activity levels of manganese superoxide dismutase (MnSOD). NAC treatment failed to induce proliferation in quiescent cells lacking MnSOD expression. These results demonstrate that NAC enhanced the recruitment of quiescent NHFs into proliferation cycle during wound healing. Our results also suggest that the wound healing properties of NAC might be due to its ability to induce and enhance MnSOD expression and activity. Altogether, these findings suggest NAC might be potentially developed as a dietary intervention to improve tissue injury in animals and humans.

  15. Modification-free and N-acetyl-L-cysteine-induced colorimetric response of AuNPs: A mechanistic study and sensitive Hg(2+) detection.

    Science.gov (United States)

    Tang, Jie; Wu, Peng; Hou, Xiandeng; Xu, Kailai

    2016-10-01

    A facile yet sensitive and selective method was proposed for Hg(2+) detection based on N-acetyl-L-cysteine(NAC)-induced colorimetric response of AuNPs. The proposed method can be easily performed by introducing the premixing of NAC and Hg(2+) into as-prepared citrate-capped AuNPs solution. A combination of experimental and theoretical studies was applied to illustrate the mechanism of this AuNPs colorimetric system. The strong interaction of NAC and AuNPs through Au-S bond could lead to the aggregation of AuNPs, but the formation of NAC-Hg-NAC complex decreased the affinity between NAC and AuNPs and resulted in an anti-aggregation effect. Therefore, the color of the AuNPs solution would progress from purple to red with the increase of Hg(2+) concentration. The proposed method had a high sensitivity with a limit of detection of 9.9nM. Coexistent metal ions, including Cd(2+), Mn(2+), Al(3+), Ag(+), K(+), Mg(2+), Ca(2+), Cr(3+), Cu(2+), Fe(3+), Pb(2+), Ni(2+) and Zn(2+), did not interfere with the detection of Hg(2+). This method can be used to monitor Hg(2+) in tap water.

  16. Protective Effects of N-Acetyl-L-Cysteine in Human Oligodendrocyte Progenitor Cells and Restoration of Motor Function in Neonatal Rats with Hypoxic-Ischemic Encephalopathy

    Directory of Open Access Journals (Sweden)

    Dongsun Park

    2015-01-01

    Full Text Available Objective. Since oligodendrocyte progenitor cells (OPCs are the target cells of neonatal hypoxic-ischemic encephalopathy (HIE, the present study was aimed at investigating the protective effects of N-acetyl-L-cysteine (NAC, a well-known antioxidant and precursor of glutathione, in OPCs as well as in neonatal rats. Methods. In in vitro study, protective effects of NAC on KCN cytotoxicity in F3.Olig2 OPCs were investigated via MTT assay and apoptotic signal analysis. In in vivo study, NAC was administered to rats with HIE induced by hypoxia-ischemia surgery at postnatal day 7, and their motor functions and white matter demyelination were analyzed. Results. NAC decreased KCN cytotoxicity in F3.Olig2 cells and especially suppressed apoptosis by regulating Bcl2 and p-ERK. Administration of NAC recovered motor functions such as the using ratio of forelimb contralateral to the injured brain, locomotor activity, and rotarod performance of neonatal HIE animals. It was also confirmed that NAC attenuated demyelination in the corpus callosum, a white matter region vulnerable to HIE. Conclusion. The results indicate that NAC exerts neuroprotective effects in vitro and in vivo by preserving OPCs, via regulation of antiapoptotic signaling, and that F3.Olig2 human OPCs could be a good tool for screening of candidates for demyelinating diseases.

  17. The Fusarium oxysporum gnt2, Encoding a Putative N-Acetylglucosamine Transferase, Is Involved in Cell Wall Architecture and Virulence

    Science.gov (United States)

    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

  18. [Nourseothricin (streptothricin) inactivated by plasmid pIE 636-encoded acetyltransferase: detection of N-acetyl-beta-lysine in the inactivated product].

    Science.gov (United States)

    Seltmann, G

    1985-12-01

    Nourseothricin (streptothricin) can be inactivated by an acetyl transferase synthesized by E. coli strains containing plasmid pIE 636. Nourseothricin inactivated in the presence of 14C-acetyl-coenzyme A was purified and submitted to partial acidic hydrolysis. By electrophoresis of the hydrolysate a 14C-containing substance moving only slowly towards the cathode could be isolated. This substance after complete hydrolysis yields only unlabelled beta-lysine.

  19. Effect of N-Acetyl Cysteine administration to the degree of parasitemia and plasma interleukin-12 level of mice infected with plasmodium berghei and treated with artemisinin

    Directory of Open Access Journals (Sweden)

    Loeki E. Fitri

    2009-03-01

    Full Text Available Introduction Protection against malaria requires a cell-mediated immune response which is initiated by releasing interleukin-12 (IL-12 from antigen presenting cells (APC. N-Acetyl Cysteine (NAC is a precursor of glutathione, while glutathione itself increases IL-12 production. Treatment with NAC combined with artemisinin is supposed to increase cellular immunity of mice during Plasmodium berghei infection. The aim of this study was to measure the effects of NAC administration on the degree of parasitemia and plasma IL-12 level in mice infected with P. berghei and treated with artemisinin.Methods The research was done using post-test-control-only design using 5 groups: group A (negative control group, group B (positive control group, or mice infected with P.berghei without therapy, group C ( mice infected by P.berghei and received artemisinin 0.04 mg/g BW for 7 days, group D (mice infected with P.berghei and received artemisinin in combination with NAC 1 mg/g BW for 7 days and group E (mice infected wirth P.berghei and received artemisinin in  combination with NAC 1 mg/g BW for 3 days and tapered into ½ mg/g BW for 4 days. Parasitemia was followed up every two days. Approximately six days post infection or when the degree of parasitemia reached ± 10% therapy was begun. On the 3rd, 5th, and 7th days post therapy, mice from each group were terminated and assayed for plasma IL-12 level (ELISA, Bender Medsystems GmbH, Vienna, cat. BMS6004.Results All mice treated with artemisinin mono-therapy and combined therapy had significantly decreased parasitemia (P=0.000. There was no significant difference (P>0.05 in decreasing parasitemia among treatment groups. The plasma IL-12 level increased significantly in both groups that received the combination of artemisinin and NAC constant dose and tapering dose compared with the group that received artemisinin mono-therapy (p < 0,05. Plasma IL-12p70 level in the combination of artemisinin and NAC tapering dose

  20. One-Step Synthesis of High-Quality Water-Soluble CdSe Quantum Dots Capped by N-Acetyl-L-cysteine via Hydrothermal Method and Their Characterization

    OpenAIRE

    Chunjin Wei; Jinyu Li; Fang Gao; Shuxia Guo; Yongcui Zhou; Dan Zhao

    2015-01-01

    Novel water-soluble CdSe quantum dots (QDs) have been prepared with N-acetyl-L-cysteine as new stabilizer through a one-step hydrothermal route. The influence of experimental conditions, including reaction time, molar ratio of reactants, and pH value, on the luminescent properties of the obtained CdSe QDs has been systematically investigated. The characterization of as-prepared QDs was carried out through different methods. In particular, we realized qualitative and semiquantitative studies o...

  1. High specific activity N-Acetyl-3{sup H}-{alpha}-Aspartyl- L-Glutamic at micro mole scale; Sintesis de N-Acetil-3{sup H}- {alpha} -Aspartil-Glutamico a escala de Micromoles

    Energy Technology Data Exchange (ETDEWEB)

    Suarez, C.

    1984-07-01

    High specific activity N-Acetyl-3{sup H}- {alpha} -Aspartyl-I-Glutamic acid at micro mole scale in prepared acetylating L- {alpha} -Aspartyl-L-glutamic with 3{sup H}-acetic anhydride in re distilled toluene. The product le purified through cationic and anionic columns. The radiochemical purity as determined by thin-layer chromatography is greater then 99% at the time preparation. (Author) 5 refs.

  2. Correlation between glomerular filtration rate and urinary N acetyl-beta-D glucosaminidase in children with persistent proteinuria in chronic glomerular disease

    Directory of Open Access Journals (Sweden)

    Jeong Deok Hong

    2012-04-01

    Full Text Available Purpose: Urinary excretion of N acetyl-beta-D glucosaminidase (NAG and ?#11437;microglobulin (?#11437;M was increased in the presence of proximal tubular damage. Based on these urinary materials, we investigated the ability of expecting renal function in chronic glomerular diseases. In this study, we evaluated the relationship between glomerular filtration rate (GFR urinary NAG, and urinary ?#11437;M. Methods: We evaluated 52 children with chronic kidney disease at the Chung-Ang University Hospital between January 2003 and August 2009. We investigated the 24-hour urinalysis and hematologic values in all 52 patients. Serum creatinine, creatinine clearance (Ccr, serum cystatin C, urinary ?#11437;M and urinary NAG were measured. Results: Out of 52 patients, there were 13 children with minimal change in disease, 3 children with focal segmental glomerulosclerosis, 17 children with immunoglobulin A nephropathy, 15 children with Henoch-Schonlein purpua nephritis, 3 children with poststreptococcal glomerulonephritis, and 1 child with thin glomerular basement membrane disease. In these patients, there were significant correlation between the Ccr and urinary NAG (r=-0.817; P&lt;0.01, and between the GFR (as determined by Schwartz method and urinary NAG (r=- 0.821; P&lt;0.01. In addition, there was a significant correlation between the GFR (as determined by Bokencamp method and urinary NAG (r=- 0.858; P&lt;0.01. Conclusion: In our study, there was a significant correlation between the GFR and urinary NAG, but there was no correlation between the GFR and urinary ?#11437;M, suggesting that the GFR can be predicted by urinary NAG in patients with chronic glomerular disease.

  3. Insights into the effect of N-acetyl-L-cysteine-capped CdTe quantum dots on the structure and activity of human serum albumin by spectroscopic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Haoyu; Yang, Xudan; Li, Meng; Han, Songlin; Liu, Yingxue [School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 27# Shanda South Road, Jinan 250100 (China); Tan, Xuejie [School of Chemistry and Pharmaceutical Engineering, Qilu University of Technology, Jinan, Shandong Province 250353 (China); Liu, Chunguang, E-mail: chunguangliu2013@sdu.edu.cn [School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 27# Shanda South Road, Jinan 250100 (China); Liu, Rutao [School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 27# Shanda South Road, Jinan 250100 (China)

    2015-11-15

    Quantum dots (QDs) are a kind of nanostructured semiconductor crystals with the size range of 1–10 nm. Their unique photophysical properties and potential toxicity to human health have aroused wide concern of scientists and general public. However, the interaction mechanism of QDs on human serum albumin (HSA, the vital protein in human blood) from both structural and functional perspectives is rarely reported. In the present work, effects of N-acetyl-L-cysteine-capped CdTe quantum dots with fluorescence emission peak at 612 nm (QDs-612) on the conformation and function of HSA were investigated by spectroscopic methods, molecular docking study and esterase activity assay. The hydrophobic interaction between HSA and QDs-612 was spontaneous with the binding constants calculated to be 6.85×10{sup 5} L mol{sup −1} (298 K) and 8.89×10{sup 5} L mol{sup −1} (308 K). The binding of QDs-612 to HSA induced the static quenching of fluorescence and the changes of secondary structure and microenvironment of Tyr-411 residue, which resulted in serious decrease on the hydrolysis of substrate p-nitrophenylacetate in esterase activity assay of HSA. This work confirms the possibility on direct interaction of QDs-612 with HSA and obtains a possible mechanism of relationship between conformation and function of HSA. - Highlights: • The interaction between CdTe QDs (QDs-612) and HSA is spontaneous. • The predominant force of the binding is hydrophobic interaction. • The interaction changes the secondary structure of HSA. • Tyr-411 residue of HSA expose to a hydrophilic environment. • The esterase activity of HSA decreases by adding QDs-612.

  4. Enhanced paracellular and transcellular paclitaxel permeation by chitosan-vitamin E succinate- N-acetyl- l-cysteine copolymer on Caco-2 cell monolayer

    Science.gov (United States)

    Lian, He; Zhang, Tianhong; Sun, Jin; Pu, Xiaohui; Tang, Yilin; Zhang, Youxi; He, Zhonggui

    2014-04-01

    The aim of this study was to evaluate the underlying mechanism of enhanced oral absorption of paclitaxel (PTX)-loaded chitosan-vitamin E succinate- N-acetyl- l-cysteine (CS-VES-NAC) nanomicelles from the cellular level. In aqueous solution, CS-VES-NAC copolymer self-assembled into the polymeric nanomicelles, with the size ranging from 190 to 240 nm and the drug loading content as high as 20.5 %. Cytotoxicity results showed that the PTX-loaded nanomicelles exhibited the similar effect to PTX solution (PTX-Sol) on Caco-2 cells, but no toxicity observed for blank CS-VES-NAC nanomicelles. The cellular uptake of PTX was significantly increased by CS-VES-NAC nanomicelles, compared with that of PTX-Sol, due to the possible escapement of P-glycoprotein (P-gp) efflux pumps by endocytosis pathway. Confocal laser scanning microscope (CLSM) images also confirmed CS-VES-NAC nanomicelles could be effectively internalized by Caco-2 cells. More importantly, P app value of PTX-loaded CS-VES-NAC nanomicelles was 2.3-fold higher than that of PTX-Sol, and the efflux ratio decreased by more than 10.8-fold for the nanomicelles. As a consequence of opening of tight junctions and P-gp inhibition induced by free CS-VES-NAC copolymer, the P app value of PTX was almost increased up to 19.5-fold. All the results indicate that CS-VES-NAC copolymer hold great promises as nanocarrier for antitumor drug oral delivery by improving paracellular and transcellular permeation.

  5. N-acetyl-seryl-aspartyl-lysyl-proline attenuates renal injury and dysfunction in hypertensive rats with reduced renal mass: council for high blood pressure research.

    Science.gov (United States)

    Liao, Tang-Dong; Yang, Xiao-Ping; D'Ambrosio, Martin; Zhang, Yanlu; Rhaleb, Nour-Eddine; Carretero, Oscar A

    2010-02-01

    N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) is a naturally occurring peptide of which the plasma concentration is increased 4- to 5-fold by angiotensin-converting enzyme inhibitors. We reported previously that, in models of both hypertension and postmyocardial infarction, Ac-SDKP reduces cardiac inflammation and fibrosis. However, it is unknown whether Ac-SDKP can prevent or reverse renal injury and dysfunction in hypertension. In the present study, we tested the hypothesis that, in rats with 5/6 nephrectomy (5/6Nx)-induced hypertension, Ac-SDKP reduces renal damage, albuminuria, and dysfunction by decreasing inflammatory cell infiltration and renal fibrosis and by increasing nephrin protein. Ac-SDKP (800 microg/kg per day, SC via osmotic minipump) or vehicle was either started 7 days before 5/6Nx (prevention) and continued for 3 weeks or started 3 weeks after 5/6Nx (reversal) and continued for another 3 weeks. Rats with 5/6Nx developed high blood pressure, left ventricular hypertrophy, albuminuria, decreased glomerular filtration rate, and increased macrophage infiltration (inflammation) and renal collagen content (fibrosis). Ac-SDKP did not affect blood pressure or left ventricular hypertrophy in either group; however, it significantly reduced albuminuria, renal inflammation, and fibrosis and improved glomerular filtration rate in both prevention and reversal groups. Moreover, slit diaphragm nephrin protein expression in the glomerular filtration barrier was significantly decreased in hypertensive rats. This effect was partially prevented or reversed by Ac-SDKP. We concluded that Ac-SDKP greatly attenuates albuminuria and renal fibrosis and improves renal function in rats with 5/6Nx. These effects may be related to decreased inflammation (macrophages) and increased nephrin protein.

  6. N-acetyl-S-(n-propyl)-l-cysteine in urine from workers exposed to 1-bromopropane in foam cushion spray adhesives.

    Science.gov (United States)

    Hanley, Kevin W; Petersen, Martin R; Cheever, Kenneth L; Luo, Lian

    2009-10-01

    1-Bromopropane (1-BP) has been marketed as an alternative for ozone depleting and other solvents; it is used in aerosol products, adhesives, metal, precision, and electronics cleaning solvents. Mechanisms of toxicity of 1-BP are not fully understood, but it may be a neurological and reproductive toxicant. Sparse exposure information prompted this study using 1-BP air sampling and urinary metabolites. Mercapturic acid conjugates are excreted in urine from 1-BP metabolism involving debromination. Research objectives were to evaluate the utility of urinary N-acetyl-S-(n-propyl)-L-cysteine (AcPrCys) for assessing exposure to 1-BP and compare it to urinary bromide [Br((-))] previously reported for these workers. Forty-eight-hour urine specimens were obtained from 30 workers at two factories where 1-BP spray adhesives were used to construct polyurethane foam seat cushions. Urine specimens were also obtained from 21 unexposed control subjects. All the workers' urine was collected into composite samples representing three time intervals: at work, after work but before bedtime, and upon awakening. Time-weighted average (TWA) geometric mean breathing zone concentrations were 92.4 and 10.5 p.p.m. for spraying and non-spraying jobs, respectively. Urinary AcPrCys showed the same trend as TWA exposures to 1-BP: higher levels were observed for sprayers. Associations of AcPrCys concentrations, adjusted for creatinine, with 1-BP TWA exposure were statistically significant for both sprayers (P < 0.05) and non-sprayers (P < 0.01). Spearman correlation coefficients for AcPrCys and Br((-)) analyses determined from the same urine specimens were highly correlated (P < 0.0001). This study confirms that urinary AcPrCys is an important 1-BP metabolite and an effective biomarker for highly exposed foam cushion workers.

  7. Synthesis and characterization of high-quality water-soluble CdMnTe quantum dots capped by N-acetyl-L-cysteine through hydrothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Fang; Li, Jiaotian; Wang, Fengxue; Yang, Tanming; Zhao, Dan, E-mail: wqzhdpai@163.com

    2015-03-15

    High-quality water-soluble Mn{sup 2+} doped CdTe quantum dots (QDs) with N-acetyl-L-cysteine (NAC) as capping reagent have been synthesized through hydrothermal route, allowing a rapid preparation time (<1 h), tunable emitting peaks (from 530 to 646 nm) and excellent quantum yields (approximately 50%). The influences of various experimental variables, including Mn-to-Cd ratio, Te-to-Cd ratio, pH value, and reaction time on the growth rate and luminescent properties of the obtained QDs have been systematically investigated. And the optimum reaction conditions (Cd:Mn:NAC:Te=1.0:1.0:2.4:0.2, pH=9.5, 35 min, 200 °C) are found out. The optical features and structure of the obtained CdMnTe QDs have been characterized through fluorescence spectroscopy, UV absorption spectroscopy and TEM. In particular, we realized qualitative, semi-quantitative and quantitative studies on the doping of Mn to CdTe QDs through XPS, EDS, and AAS. The actual molar ratio of Mn to Cd in CdMnTe QDs (551 nm) is 1.166:1.00, very close to the feed ratios (1:1). - Highlights: • Mn doped CdTe QDs have been synthesized through one-pot hydrothermal route. • The prepared QDs possess excellent quantum yields as high as 63.1% and tunable emitting peaks from 530 to 646 nm. • We found out that the enhancement of Mn:Cd will decrease the QY of the prepared QDs and lead to the blueshift of emission peaks. • The QDs have been characterized through TEM, EDS, XPS, and AAS.

  8. [Pharmacological effects of N-acetyl-L-cysteine on the respiratory tract. (I). Quantitative and qualitative changes in respiratory tract fluid and sputum (author's transl)].

    Science.gov (United States)

    Kogi, K; Saito, T; Kasé, Y; Hitoshi, T

    1981-06-01

    The following three experiments were performed to determine the effects of N-acetyl-L-cysteine (NAC) on the quantity and quality of respiratory tract fluid (RTF) and sputum. All drugs used were administered into the stomach through a gastric tube. 1) Indirect measurement of bronchial secretion in rats, which was expressed by the amounts of dye excreted into the respiratory tract, was carried out according the the Sakuno's method, with some modification. Some expectorants of the secretomotor type, such as bromhexine and pilocarpine, significantly increased the secretion, even at low doses. On the other hand, mucolytic agents such as NAC augmented the secretion only in doses of 500 to 1500 mg/kg. 2)As a direct method of measurements, Kasé's modification of Perry and Boyd's method was used to collect RTF, quantitatively, from rabbits. The RTF of healthy rabbits was colorless and watery. The administration of NAC in doses of 500 to 1500 mg/kg augmented the output volume and RTF became slightly turbid, probably due to an increase in the viscous mucus. 3) Rabbits with subacute bronchitis were prepared by long-term exposure to air contaminated with SO2 gas and sputa were collected before and after administration of NAC, respectively, according to the Kase's method. The sputa were opalescent and viscous gel included nodular masses. The administration of NAC, 1000 and 1500 mg/kg resulted in a dose dependent decrease in the relative viscosity. The percent-decreased in viscosity with NAC was statistically correlated with that in amounts of dry matter, those in protein and polysaccharide in the sputa. From the results described above, it was concluded that NAC given into the stomach can liquefy sputum by splitting mucoprotein disulphide linkages, that is, altering the rheological characteristics of sputum to facilitate expectoration.

  9. Damage of tubule cells in diabetic nephropathy type 2: Urinary N-acetyl-β-D-glucosaminidasis and γ-glutamil-transferasis

    Directory of Open Access Journals (Sweden)

    Vlatković Vlastimir

    2007-01-01

    Full Text Available Background/Aim. A damage of tubular epithelial cells is followed by the release of cell enzymes and production of proinflammatory compounds, which lead to the tubulointerstitial damage. The aim of this study was to examine the function of renal tubules in the patients with diabetes mellitus type 2 (DM type 2 and the various proteinuria degrees, to establish the damage of the proximal tubule cells caused by DM type 2 by determining urinary N-acetyl-β-D-glucosaminidasis (β-NAG and γ- glutamil-transferasis (γ-GT activity in urine, as well as to compare the obtained results in the examined groups of patients with the values in the healthy examinees. Methods. A complete examination of renal function and selective enzymuria was performed in 37 patients with DM type 2, and 14 healthy examinees as the controls. The patients were divided in three groups according to the degree of proteinuria. The first group consisted of the patients with diabetes without microalbuminuria; the second one consisted of the patients with proteinuria of < 300 mg/24 h, and microalbuminuria of >20 mg/24 h, while the third one included the patients with proteinuria of >300 mg/24 h. Results. In the patients with DM type 2 and the preserved global renal function, fractional excretion of sodium, potassium and phosphates, as well as renal threshold of phosphates concentration, were not sensitive parameters for discovering the damage of the renal tubule function. The determination of β-NAG activity proved to be the most sensitive parameter for early discovering of tubule cells damages. The difference among the examined groups was statistically highly significant. Conclusion. The increased presence of β-NAG in the urine of DM type 2 patients, pointed out an early tubular disorder and damage of cells, while γ-GT was a less sensitive indicator of this damage.

  10. Efficacy of intravenous administration of hyaluronan, sodium chondroitin sulfate, and N-acetyl-d-glucosamine for prevention or treatment of osteoarthritis in horses.

    Science.gov (United States)

    Frisbie, David D; McIlwraith, C Wayne; Kawcak, Christopher E; Werpy, Natasha M

    2016-10-01

    OBJECTIVE To evaluate the efficacy of IV administration of a product containing hyaluronan, sodium chondroitin sulfate, and N-acetyl-d-glucosamine for prevention or treatment of osteoarthritis in horses. ANIMALS 32 healthy 2- to 5-year-old horses. PROCEDURES The study involved 2 portions. To evaluate prophylactic efficacy of the test product, horses received 5 mL of the product (n = 8) or saline (0.9% NaCl) solution (8; placebo) IV every fifth day, starting on day 0 (when osteoarthritis was induced in the middle carpal joint of 1 forelimb) and ending on day 70. To evaluate treatment efficacy, horses received either the product or placebo (n = 8/treatment) on days 16, 23, 30, 37, and 44 after osteoarthritis induction. Clinical, diagnostic imaging, synovial fluid, gross anatomic, and histologic evaluations and other tests were performed. Results of each study portion were compared between treatment groups. RESULTS Limb flexion and radiographic findings were significantly worse for horses that received the test product in the prophylactic efficacy portion than for placebo-treated horses or product-treated horses in the treatment efficacy portion. In the prophylactic efficacy portion, significantly less articular cartilage erosion was identified in product-treated versus placebo-treated horses. In the treatment efficacy portion, joints of product-treated horses had a greater degree of bone edema identified via MRI than did joints of placebo-treated horses but fewer microscopic articular cartilage abnormalities. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that caution should be used when administering the evaluated product IV to horses, particularly when administering it prophylactically, as it may have no benefit or may even cause harm.

  11. The accumulation of un-repairable DNA damage in laminopathy progeria fibroblasts is caused by ROS generation and is prevented by treatment with N-acetyl cysteine.

    Science.gov (United States)

    Richards, Shane A; Muter, Joanne; Ritchie, Pamela; Lattanzi, Giovanna; Hutchison, Christopher J

    2011-10-15

    Fibroblasts from patients with the severe laminopathy diseases, restrictive dermopathy (RD) and Hutchinson Gilford progeria syndrome (HGPS), are characterized by poor growth in culture, the presence of abnormally shaped nuclei and the accumulation of DNA double-strand breaks (DSB). Here we show that the accumulation of DSB and poor growth of the fibroblasts but not the presence of abnormally shaped nuclei are caused by elevated levels of reactive oxygen species (ROS) and greater sensitivity to oxidative stress. Basal levels of ROS and sensitivity to H(2)O(2) were compared in fibroblasts from normal, RD and HGPS individuals using fluorescence activated cell sorting-based assays. Basal levels of ROS and stimulated levels of ROS were both 5-fold higher in the progeria fibroblasts. Elevated levels of ROS were correlated with lower proliferation indices but not with the presence of abnormally shaped nuclei. DSB induced by etoposide were repaired efficiently in normal, RD and HGPS fibroblasts. In contrast, DSB induced by ROS were repaired efficiently in normal fibroblasts, but in RD and HGPS fibroblasts many ROS-induced DSB were un-repairable. The accumulation of ROS-induced DSB appeared to cause the poor growth of RD and HGPS fibroblasts, since culture in the presence of the ROS scavenger N-acetyl cysteine (NAC) reduced the basal levels of DSB, eliminated un-repairable ROS-induced DSB and greatly improved population-doubling times. Our findings suggest that un-repaired ROS-induced DSB contribute significantly to the RD and HGPS phenotypes and that inclusion of NAC in a combinatorial therapy might prove beneficial to HGPS patients.

  12. Assessment of protective effects of glucosamine and N-acetyl glucosamine against DNA damage induced by hydrogen peroxide in human lymphocytes.

    Science.gov (United States)

    Jamialahmadi, Khadijeh; Soltani, Fatemeh; Nabavi Fard, Maryam; Behravan, Javad; Mosaffa, Fatemeh

    2014-10-01

    The antigenotoxic activity of glucosamine (GlcN) and N-acetylglucosamine (GlcNAc) in human peripheral lymphocytes exposed to oxidative stress was investigated. Human lymphocytes were treated with different concentrations of these aminosugars (0, 2.5, 5, 10, 20 and 40 mM) and 25 µM H2O2 simultaneously and evaluated by single cell gel electrophoresis technique (Comet assay). The single cells were analyzed using "TriTek Cometscore version 1.5" software and the data were presented as % DNA in tail. Both GlcN and GlcNAc at examined concentrations (2.5, 5, 10, 20 and 40 mM) did not reveal any genotoxicity compared to the vehicle control (PBS). Glucosamine at all concentrations (2.5, 5, 10, 20 and 40 mM) showed a significant protective activity (% DNA in tail ranging from 16.07 ± 0.85 to 5.47 ± 0.26, p < 0.001) against H2O2 induced DNA damage (% DNA in tail = 38 ± 0.65) while its N-acetylated analog only indicated a slight DNA protection at concentration of 40 mM (% DNA in tail = 33.4 ± 1.17, p < 0.01). We concluded that GlcN at tested concentrations exhibited potent antigenotoxic effect and its protection activity might be related to the presence of 2-NH2 moiety in its chemical backbone.

  13. N-acetyl-beta-D-hexosaminidase and its isoenzymes A and B in blood serum and urine, as a potential colon cancer markers.

    Science.gov (United States)

    Szajda, Sławomir Dariusz; Borzym-Kluczyk, Małgorzata; Snarska, Jadwiga; Puchalski, Zbigniew; Zwierz, Krzysztof

    2009-01-01

    Evaluation of N-acetyl-beta-D-hexosaminidase (HEX), and its isoenzymes A (HEX A) and B (HEX B) activity in blood serum and urine as potential markers of colorectal cancer. The study was performed in blood serum and urine of 32 patients with adenocarcinoma, 6 with adenocarcinoma mucinosum of the colon, and 20 healthy people. The activity of HEX, HEX A and HEX B was determined in blood serum and urine by spectrophotometric method of Marciniak et al. The concentration of CEA was determined in blood serum by immunoenzymatic method (MEIA). The concentration of protein was assessed by the Lowry method, whereas the concentration of creatinine in urine by the Jaffe method (without deproteinization). A significant increase in the concentration of HEX, HEX A and HEX B activity was proved in serum and urine of patients with colon adenocarcinoma. In patients with colon adenocarcinoma mucinosum, the higher activity of HEX was revealed in blood serum compared to healthy people, and the significantly higher activity of HEX and HEX B expressed as pKat/mg of creatinine, was found in urine. We observe a significant increase in the activity of HEX, HEX A and HEX B expressed in pKat/mg of creatinine was found in urine of patients bearing tumor of diameter 6.0-7.0 cm in comparison to patients with tumor of diameter 4.0-5.0 cm. The present study results suggest that determination of HEX, HEX A and HEX B activity in blood serum and urine may be used to detect colon cancer in its early stages. However, the use of HEX, HEX A and HEX B activity in oncological diagnostics requires further studies on a larger group of patients.

  14. Activity of N-acetyl-beta-D-hexosaminidase (HEX) and its isoenzymes A and B in human milk during the first 3 months of breastfeeding.

    Science.gov (United States)

    Dudzik, D; Knas, M; Gocal, M; Borzym-Kluczyk, M; Szajda, S D; Knaś-Karaszewska, K; Tomaszewski, J; Zwierz, K

    2008-01-01

    Milk contains free and bound oligo- and heteropolisaccharides, which protect newborns against pathogens and have nutritional value. N-acetyl-beta-D-hexosaminidase (HEX), the most active lysosomal exoglycosidase, modify and degrade oligo- and heteropolysaccharides. The objective of our study was to determine HEX activity and isoenzymes A and B in the progression of lactation. Human milk samples were collected from 51 women on the 3rd, 21st and 100th day postpartum. Enzymatic activity was determined the Zwierz et al method modified by Marciniak et al. Protein and lactose concentrations were determined by a MilkoScan 4000 apparatus. The total HEX activity decreased by the 21st day in comparison to the 3rd day, and increased by the 100th day as compared to the 21st day. HEX A activity decreased by the 21st and the 100th day as compared to the 3rd day. HEX B activity decreased by 21st day and has the tendency to decrease by the 100th day as compared to the 3rd day. Protein concentration decreased and the lactose concentration increased in milk taken on the 21st day in comparison to concentration of protein and lactose on the 3rd day. HEX and its isoenzymes' activity significantly correlate with the progression of lactation. At the beginning of lactation, HEX A activity, which releases hexosamines from acidic oligosaccharides, dominates; later, HEX B releases hexosamines from neutral oligosaccharides. To better understand the degradation of human milk oligosaccharides, it would be useful to investigate and document their detailed structures and evaluate the activity of other exoglycosidases' activity in human breast milk over the course of lactation.

  15. [Concentration of thyroid stimulating hormone and activity of N-acetyl-beta-D-hexosaminidase and its isoenzymes, in serum of patients with thyroid cancer].

    Science.gov (United States)

    Zwierz, Piotr; Szajda, Sławomir D; Snarska, Jadwiga; Supronowicz, Zbigniew B; Zawadzki, Paweł; Zwierz, Krzysztof; Kamińsk, Fabian

    2006-11-01

    Thyroid cancer consists 1% of all malignant neoplasms. It is not known interrelationship between concentration of TSH in blood serum and condition of thyroid cancer. Thyroid cancer is difficult for diagnosis and differentiation. Therefore it is necessary to search for biochemical markers helpful in diagnostics of thyroid cancer. Significant increase in activity of N-acetyl-beta-D-hexosaminidase and its isoenzymes A and B in serum of patients with neoplasms of kidney and pancreas suggest approporiateness of evaluation of HEX and its isoenzymes in diagnostics of thyroid cancer. of the study--evaluation of TSH concentration and activity of HEX and its isoenzymes A and B, in serum of patients with thyroid cancer. Blood was taken from 7 patients with thyroid cancer (6 men and 1 woman). Control consisted of 7 healthy men. In blood serum concentration of TSH was determined with immunoenzymatic method on analyzer Axsym of Abbott and expressed in microU/mL. The activity of HEX and its isoenzymes A and B was determined by method of Chatterjee et al., as modified by Zwierz et.al. Determination of HEX was performed on microplate reader ELX800 BIO-TEK. Activity of HEX, HEX A and B was expressed in pKat/mL, and specific activity in pKat/mg protein). Protein was determined by biuret method and results were expressed in mg/mL. Concentration of HEX A activity in serum of thyroid cancer patients is significantly higherin comparison to healthymen (p = 0.0191). Also specific activity of HEX A in serum of thyroid cancer patients is significantly higher in comparison to healthy men (p = 0.0393). 1. Determination of TSH concentration in serum of thyroid cancer before the operation may confirm euthyreosis. 2. Determination of HEX A activity in serum may be helpful in diagnostics of thyroid cancer.

  16. pH-dependent optical properties of N-acetyl-L-cysteine-capped ZnSe(S) nanocrystals with intense/stable emissions

    Science.gov (United States)

    Soheyli, Ehsan; Sahraei, Reza; Nabiyouni, Gholamreza

    2017-03-01

    In the present study, a series of aqueous-based ZnSe(S) nanocrystals (NCs) was prepared at different solution pH ranging from 8 to 11.9, and using N-acetyl-L-cysteine (NAC) as capping agent. In addition to zinc blende structure, the X-ray diffraction studies demonstrated the quantum size regime of the ZnSe(S) NCs. To gain further insight toward the influence of the quantum confinement and pH values on optical properties of the as-prepared NCs, their UV-visible absorption and photoluminescence spectra were systematically analyzed. The absorption spectra experienced a red shift from 340 to 382 nm as the pH increased from 8.0 to 11.9, indicating the growth of the as-prepared ZnSe(S) NCs. The emission spectra also show the obvious red shift and the relative area of excitonic to trap emission, firstly increases from pH = 8.0 to 10.7, and then decreases by further increasing of the solution pH. The initial behavior might be due to the improved surface passivation of the trap dangling states by better deprotonation of thiol groups in NAC, whereas at pH >10.7, the faster growth rate of the ZnSe(s) NCs may lead to the formation of many defect sites. All of these phenomena were combined in the scheme which displays the effect of quantum confinement and solution pH on variation of the excitonic and trap-related emissions.

  17. N-Acetyl-L-cysteine and pyrrolidine dithiocarbamate inhibited nuclear factor-кB activation in alveolar macrophages by different mechanisms

    Institute of Scientific and Technical Information of China (English)

    Ya-qing LI; Zhen-xiang ZHANG; Yong-jian XU; Wang NI; Shi-xin CHEN; Zhao YANG; Dan MA

    2006-01-01

    Aim:To study the effects of N-acetyl-L-cysteine(NAC)and pyrrolidine dithiocarbamate(PDTC)on the phosphorylation of IκB kinase(IKK)β,IKKα,and IκBa in alveolar macrophages(AM),and to explore the pharmacological mechanisms of NAC and PDTC as inhibitors of NF-κB activation.Methods:AM were collected from bronchoalveolar lavage fluid from the patients with chronic obstructive pulmonary disease.The AM were incubated for 1.5h with NAC and PDTC,and then stimulated for 90 min by either tumor necrosis factor(TNF)-α or interleukin(IL)-1.Western blotting was used to detect the protein phosphorylation levels of IKKβ,IKKα,and IκBα.NF-κB activity was analyzed by using an electrophoretic mobility shift assay.Resuits:NAC inhibited the phosphorylation of IKKβ,IKKα,and IκBα induced by TNF-α,but had no effect on the phosphorylation of IKKβ,IKKα and IκBα induced by IL-1.PDTC did not inhibit the phosphorylation of IκBα induced by TNF-α or IL-1.Similarly,NAC inhibited the activation of NF-κB induced by TNF-α,but had no effect on the activation of NF-κB induced by IL-1.PDTC significantly inhibited the activation of NF-κB induced by TNF-α and IL-1.The electrophoretic mobility shift assay also showed that PDTC and NAC do not directly inhibit NF-κB DNA binding activity in vitro.Conclusion:PDTC prevents the degradation of IκBα via the ubiquitylation-proteasome proteolytic pathway.NAC can inhibit the processes upstream of IKK activation induced by TNF-α,which results in the decline of NF-κB activity.

  18. N-Acetyl-D-Glucosamine Kinase Interacts with Dynein-Lis1-NudE1 Complex and Regulates Cell Division.

    Science.gov (United States)

    Sharif, Syeda Ridita; Islam, Ariful; Moon, Il Soo

    2016-09-01

    N-acetyl-D-glucosamine kinase (GlcNAc kinase or NAGK) primarily catalyzes phosphoryl transfer to GlcNAc during amino sugar metabolism. Recently, it was shown NAGK interacts with dynein light chain roadblock type 1 (DYNLRB1) and upregulates axo-dendritic growth, which is an enzyme activity-independent, non-canonical structural role. The authors examined the distributions of NAGK and NAGK-dynein complexes during the cell cycle in HEK293T cells. NAGK was expressed throughout different stages of cell division and immunocytochemistry (ICC) showed NAGK was localized at nuclear envelope, spindle microtubules (MTs), and kinetochores (KTs). A proximity ligation assay (PLA) for NAGK and DYNLRB1 revealed NAGK-dynein complex on nuclear envelopes in prophase cells and on chromosomes in metaphase cells. NAGK-DYNLRB1 PLA followed by Lis1/NudE1 immunostaining showed NAGK-dynein complexes were colocalized with Lis1 and NudE1 signals, and PLA for NAGK-Lis1 showed similar signal patterns, suggesting a functional link between NAGK and dynein-Lis1 complex. Subsequently, NAGK-dynein complexes were found in KTs and on nuclear membranes where KTs were marked with CENP-B ICC and nuclear membrane with lamin ICC. Furthermore, knockdown of NAGK by small hairpin (sh) RNA was found to delay cell division. These results indicate that the NAGK-dynein interaction with the involvements of Lis1 and NudE1 plays an important role in prophase nuclear envelope breakdown (NEB) and metaphase MT-KT attachment during eukaryotic cell division.

  19. N-Acetyl-L-Cysteine Affords Protection against Lead-Induced Cytotoxicity and Oxidative Stress in Human Liver Carcinoma (HepG2 Cells

    Directory of Open Access Journals (Sweden)

    Paul B. Tchounwou

    2007-06-01

    Full Text Available Although lead exposure has declined in recent years as a result of change to lead-free gasoline, several epidemiological have pointed out that it represents a medical and public health emergency, especially in young children consuming high amounts of lead-contaminated flake paints. A previous study in our laboratory indicated that lead exposure induces cytotoxicity in human liver carcinoma cells. In the present study, we evaluated the role of oxidative stress in lead-induced toxicity, and the protective effect of the anti-oxidant n-acetyl-l-cysteine (NAC. We hypothesized that oxidative stress plays a role in lead-induced cytotoxicity, and that NAC affords protection against this adverse effect. To test this hypothesis, we performed the MTT [3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide] assay and the trypan blue exclusion test for cell viability. We also performed the thiobarbituric acid test for lipid peroxidation. Data obtained from the MTT assay indicated that NAC significantly increased the viability of HepG2 cells in a dosedependent manner upon 48 hours of exposure. Similar trend was obtained with the trypan blue exclusion test. Data generated from the thiobarbituric acid test showed a significant (p ≤ 0.05 increase of MDA levels in lead nitrate-treated HepG2 cells compared to control cells. Interestingly, the addition of NAC to lead nitrate-treated HepG2 cells significantly decreased cellular content of reactive oxygen species (ROS, as evidenced by the decrease in lipid peroxidation byproducts. Overall, findings from this study suggest that NAC inhibits lead nitrate-induced cytotoxicity and oxidative stress in HepG2 cells. Hence, NAC may be used as a salvage therapy for lead-induced toxicity in exposed persons.

  20. Arsenic Metabolites, Including N-Acetyl-4-hydroxy-m-arsanilic Acid, in Chicken Litter from a Roxarsone-Feeding Study Involving 1600 Chickens.

    Science.gov (United States)

    Yang, Zonglin; Peng, Hanyong; Lu, Xiufen; Liu, Qingqing; Huang, Rongfu; Hu, Bin; Kachanoski, Gary; Zuidhof, Martin J; Le, X Chris

    2016-07-01

    The poultry industry has used organoarsenicals, such as 3-nitro-4-hydroxyphenylarsonic acid (Roxarsone, ROX), to prevent disease and to promote growth. Although previous studies have analyzed arsenic species in chicken litter after composting or after application to agricultural lands, it is not clear what arsenic species were excreted by chickens before biotransformation of arsenic species during composting. We describe here the identification and quantitation of arsenic species in chicken litter repeatedly collected on days 14, 24, 28, 30, and 35 of a Roxarsone-feeding study involving 1600 chickens of two strains. High performance liquid chromatography separation with simultaneous detection by both inductively coupled plasma mass spectrometry and electrospray ionization tandem mass spectrometry provided complementary information necessary for the identification and quantitation of arsenic species. A new metabolite, N-acetyl-4-hydroxy-m-arsanilic acid (N-AHAA), was identified, and it accounted for 3-12% of total arsenic. Speciation analyses of litter samples collected from ROX-fed chickens on days 14, 24, 28, 30, and 35 showed the presence of N-AHAA, 3-amino-4-hydroxyphenylarsonic acid (3-AHPAA), inorganic arsenite (As(III)), arsenate (As(V)), monomethylarsonic acid (MMA(V)), dimethylarsinic acid (DMA(V)), and ROX. 3-AHPAA accounted for 3-19% of the total arsenic. Inorganic arsenicals (the sum of As(III) and As(V)) comprised 2-6% (mean 3.5%) of total arsenic. Our results on the detection of inorganic arsenicals, methylarsenicals, 3-AHPAA, and N-AHAA in the chicken litter support recent findings that ROX is actually metabolized by the chicken or its gut microbiome. The presence of the toxic metabolites in chicken litter is environmentally relevant as chicken litter is commonly used as fertilizer.

  1. Characterization of the N-Acetyl-5-neuraminic Acid-binding Site of the Extracytoplasmic Solute Receptor (SiaP) of Nontypeable Haemophilus influenzae Strain 2019

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, Jason W.; Coussens, Nathan P.; Allen, Simon; Houtman, Jon C.D.; Turner, Keith H.; Zaleski, Anthony; Ramaswamy, S.; Gibson, Bradford W.; Apicella, Michael A. (Iowa); (Buck Inst.)

    2012-11-14

    Nontypeable Haemophilus influenzae is an opportunistic human pathogen causing otitis media in children and chronic bronchitis and pneumonia in patients with chronic obstructive pulmonary disease. The outer membrane of nontypeable H. influenzae is dominated by lipooligosaccharides (LOS), many of which incorporate sialic acid as a terminal nonreducing sugar. Sialic acid has been demonstrated to be an important factor in the survival of the bacteria within the host environment. H. influenzae is incapable of synthesizing sialic acid and is dependent on scavenging free sialic acid from the host environment. To achieve this, H. influenzae utilizes a tripartite ATP-independent periplasmic transporter. In this study, we characterize the binding site of the extracytoplasmic solute receptor (SiaP) from nontypeable H. influenzae strain 2019. A crystal structure of N-acetyl-5-neuraminic acid (Neu5Ac)-bound SiaP was determined to 1.4 {angstrom} resolution. Thermodynamic characterization of Neu5Ac binding shows this interaction is enthalpically driven with a substantial unfavorable contribution from entropy. This is expected because the binding of SiaP to Neu5Ac is mediated by numerous hydrogen bonds and has several buried water molecules. Point mutations targeting specific amino acids were introduced in the putative binding site. Complementation with the mutated siaP constructs resulted either in full, partial, or no complementation, depending on the role of specific residues. Mass spectrometry analysis of the O-deacylated LOS of the R127K point mutation confirmed the observation of reduced incorporation of Neu5Ac into the LOS. The decreased ability of H. influenzae to import sialic acid had negative effects on resistance to complement-mediated killing and viability of biofilms in vitro, confirming the importance of sialic acid transport to the bacterium.

  2. Comparison of modified Petroff′s and N-acetyl-L-cysteine-sodium hydroxide methods for sputum decontamination in tertiary care hospital in India

    Directory of Open Access Journals (Sweden)

    Mukesh Sharma

    2012-01-01

    Full Text Available Background : Tuberculosis is the second leading cause of death worldwide, killing nearly two million people each year. Sputum decontamination with N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH is expected to improve detection of Mycobacterium tuberculosis (M. tb by culture better than that with modified Petroff′s; which is widely used in laboratories. In this study, sputum samples collected from suspected cases of pulmonary tuberculosis (TB were cultured directly on Lowenstein-Jensen (LJ medium and after decontamination by both the methods and the results of smear and culture positivity were evaluated to assess whether the NALC-NaOH treatment method improves smear and culture. Materials and Methods : For each decontamination method, 30 samples were obtained from suspected cases of Pulmonary TB, from Pad. Dr. D.Y. Patil Medical College and Hospital. Two sputum samples from each patient were collected on day 1 and 2. These samples then underwent decontamination process by performing the 4% NaOH, NALC-2% NaOH treatment methods and direct inoculation. After each process a smear was made and culture was done on LJ medium. Results: The modified Petroff′s and NALC-NaOH treatment methods did not significantly affect the AFB smear positivity of the sputum samples (66% and 72.3%, respectively. (However, the culture positivity for M. tb on LJ medium was significantly different by the three processes. With NALC-NaOH and modified Petroff′s it was 63% and 46%, respectively, while with direct culture it was 23%. Conclusion: NALC-NaOH treatment is better than modified Petroff′s treatment for the detection of M. tb by culture. However, AFB microscopy does not seem to be significantly different by either process.

  3. Biodegradable poly(lactic-co-glycolic acid) microspheres loaded with S-nitroso-N-acetyl-D-penicillamine for controlled nitric oxide delivery.

    Science.gov (United States)

    Lautner, Gergely; Meyerhoff, Mark E; Schwendeman, Steven P

    2016-03-10

    Nitric oxide (NO) is a fascinating and important endogenous free-radical gas with potent antimicrobial, vasodilating, smooth muscle relaxant, and growth factor stimulating effects. However, its wider biomedical applicability is hindered by its cumbersome administration, since NO is unstable especially in biological environments. In this work, to ultimately develop site-specific controlled release vehicles for NO, the NO donor S-nitroso-N-acetyl-D-penicillamine (SNAP) was encapsulated within poly(lactic-co-glycolic acid) 50:50 (PLGA) microspheres by using a solid-in-oil-in-water emulsion solvent evaporation method. The highest payload was 0.56(±0.01) μmol SNAP/mg microspheres. The in vitro release kinetics of the donor were controlled by the bioerosion of the PLGA microspheres. By using an uncapped PLGA (Mw=24,000-38,000) SNAP was slowly released for over 10days, whereas by using the ester capped PLGA (Mw=38,000-54,000) the release lasted for over 4weeks. The presence of copper ions and/or ascorbate in solution was necessary to efficiently decompose the released NO donor and obtain sustained NO release. It was also demonstrated that light can be used to induce rapid NO release from the microspheres over several hours. SNAP exhibited excellent storage stability when encapsulated in the PLGA microspheres. These new microsphere formulations may be useful for site-specific administration and treatment of pathologies associated with dysfunction in endogenous NO production, e.g. treatment of diabetic wounds, or in diseases involving other biological functions of NO including vasodilation, antimicrobial, anticancer, and neurotransmission. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Characterization of the N-acetyl-5-neuraminic acid-binding site of the extracytoplasmic solute receptor (SiaP) of nontypeable Haemophilus influenzae strain 2019.

    Science.gov (United States)

    Johnston, Jason W; Coussens, Nathan P; Allen, Simon; Houtman, Jon C D; Turner, Keith H; Zaleski, Anthony; Ramaswamy, S; Gibson, Bradford W; Apicella, Michael A

    2008-01-11

    Nontypeable Haemophilus influenzae is an opportunistic human pathogen causing otitis media in children and chronic bronchitis and pneumonia in patients with chronic obstructive pulmonary disease. The outer membrane of nontypeable H. influenzae is dominated by lipooligosaccharides (LOS), many of which incorporate sialic acid as a terminal nonreducing sugar. Sialic acid has been demonstrated to be an important factor in the survival of the bacteria within the host environment. H. influenzae is incapable of synthesizing sialic acid and is dependent on scavenging free sialic acid from the host environment. To achieve this, H. influenzae utilizes a tripartite ATP-independent periplasmic transporter. In this study, we characterize the binding site of the extracytoplasmic solute receptor (SiaP) from nontypeable H. influenzae strain 2019. A crystal structure of N-acetyl-5-neuraminic acid (Neu5Ac)-bound SiaP was determined to 1.4A resolution. Thermodynamic characterization of Neu5Ac binding shows this interaction is enthalpically driven with a substantial unfavorable contribution from entropy. This is expected because the binding of SiaP to Neu5Ac is mediated by numerous hydrogen bonds and has several buried water molecules. Point mutations targeting specific amino acids were introduced in the putative binding site. Complementation with the mutated siaP constructs resulted either in full, partial, or no complementation, depending on the role of specific residues. Mass spectrometry analysis of the O-deacylated LOS of the R127K point mutation confirmed the observation of reduced incorporation of Neu5Ac into the LOS. The decreased ability of H. influenzae to import sialic acid had negative effects on resistance to complement-mediated killing and viability of biofilms in vitro, confirming the importance of sialic acid transport to the bacterium.

  5. Cadmium-induced oxidative damage and protective effects of N-acetyl-L-cysteine against cadmium toxicity in Solanum nigrum L

    Energy Technology Data Exchange (ETDEWEB)

    Deng Xiaopeng; Xia Yan; Hu Wei [College of Life Sciences, Nanjing Agricultural University, Weigang 1, Nanjing 210095 (China); Zhang Hongxiao, E-mail: hxzhang@njau.edu.cn [College of Life Sciences, Nanjing Agricultural University, Weigang 1, Nanjing 210095 (China); Shen Zhenguo, E-mail: zgshen@njau.edu.cn [College of Life Sciences, Nanjing Agricultural University, Weigang 1, Nanjing 210095 (China)

    2010-08-15

    The effects of cadmium (Cd) on the accumulation of hydrogen peroxide (H{sub 2}O{sub 2}) and antioxidant enzyme activities in roots of Solanum nigrum L. and the role of N-acetyl-L-cysteine (NAC) as a cysteine (Cys) donor against Cd toxicity were investigated. Cd at 50 and 200 {mu}M significantly increased the contents of thiobarbituric acid-reactive substances (TBARS), the production of H{sub 2}O{sub 2} and superoxide anion (O{sub 2}{center_dot}{sup -}), and the activities of catalase, guaiacol peroxidase, ascorbate peroxidase, glutathione peroxidase (GSH-Px), glutathione reductase, and superoxide dismutase. Experiments with diphenylene iodonium as an inhibitor of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and NaN{sub 3} as an inhibitor of peroxidase showed that the major source of Cd-induced reactive oxygen species in the roots may include plasma membrane-bound NADPH oxidase and peroxidase. In addition, the effects of NAC on plant growth, antioxidant enzyme activity, and non-protein thiol content were analyzed. Under Cd stress, the addition of 500 {mu}M NAC decreased the contents of TBARS and production of H{sub 2}O{sub 2} and O{sub 2}{center_dot}{sup -}, but increased levels of Cys and reduced glutathione (GSH), phytochelatins, and activity of GSH-Px in roots. These results suggest that NAC could protect plants from oxidative stress damage, and this protection seems to be performed via increased GSH biosynthesis. Furthermore, NAC treatment also increased the contents of protein thiols in S. nigrum roots. By using size-exclusion chromatography, we found involvement of NAC in the Cd tolerance mechanism through increased biosynthesis of Cd-binding proteins.

  6. N-Acetyl-Cysteine and l-Carnitine Prevent Meiotic Oocyte Damage Induced by Follicular Fluid From Infertile Women With Mild Endometriosis.

    Science.gov (United States)

    Giorgi, Vanessa S I; Da Broi, Michele G; Paz, Claudia C P; Ferriani, Rui A; Navarro, Paula A

    2016-03-01

    This study evaluated the potential protective effect of the antioxidants, l-carnitine (LC) and N-acetyl-cysteine (NAC), in preventing meiotic oocyte damage induced by follicular fluid (FF) from infertile women with mild endometriosis (ME). We performed an experimental study. The FF samples were obtained from 22 infertile women undergoing stimulated cycles for intracytoplasmic sperm injection (11 with ME and 11 without endometriosis). Immature bovine oocytes were submitted to in vitro maturation (IVM) divided into 9 groups: no-FF (No-FF); with FF from control (CFF) or ME (EFF) groups; and with LC (C + LC and E + LC), NAC (C + NAC and E + NAC), or both antioxidants (C + 2Ao and E + 2Ao). After IVM, oocytes were immunostained for visualization of microtubules and chromatin by confocal microscopy. The percentage of meiotically normal metaphase II (MII) oocytes was significantly lower in the EFF group (51.35%) compared to No-FF (86.36%) and CFF (83.52%) groups. The E + NAC (62.22%), E + LC (80.61%), and E + 2Ao (61.40%) groups showed higher percentage of normal MII than EFF group. The E + LC group showed higher percentage of normal MII than E + NAC and E + 2Ao groups and a similar percentage to No-FF and CFF groups. Therefore, FF from infertile women with ME causes meiotic abnormalities in bovine oocytes, and, for the first time, we demonstrated that the use of NAC and LC prevents these damages. Our findings elucidate part of the pathogenic mechanisms involved in infertility associated with ME and open perspectives for further studies investigating whether the use of LC could improve the natural fertility and/or the results of in vitro fertilization of women with ME.

  7. Sensitive Electrochemiluminescence Immunosensor for Detection of N-Acetyl-β-d-glucosaminidase Based on a "Light-Switch" Molecule Combined with DNA Dendrimer.

    Science.gov (United States)

    Wang, Haijun; Yuan, Yali; Zhuo, Ying; Chai, Yaqin; Yuan, Ruo

    2016-06-07

    Here, a novel "light-switch" molecule of Ru (II) complex ([Ru(dcbpy)2dppz](2+)-DPEA) with self-enhanced electrochemiluminescence (ECL) property is proposed, which is almost nonemissive in aqueous solution but is brightly luminescent when it intercalates into DNA duplex. Owing to less energy loss and shorter electron-transfer distance, the intramolecular ECL reaction between the luminescent [Ru(dcbpy)2dppz](2+) and coreactive tertiary amine group in N,N-diisopropylethylenediamine (DPEA) makes the obtained "light-switch" molecule possess much higher light-switch efficiency compared with the traditional "light-switch" molecule. For increasing the loading amount and further enhancing the luminous efficiency of the "light-switch" molecule, biotin labeled DNA dendrimer (the fourth generation, G4) is prepared from Y-shape DNA by a step-by-step assembly strategy, which provides abundant intercalated sites for [Ru(dcbpy)2dppz](2+)-DPEA. Meanwhile, the obtained nanocomposite (G4-[Ru(dcbpy)2dppz](2+)-DPEA) could well bind with streptavidin labeled detection antibody (SA-Ab2) due to the existence of abundant biotin. Through sandwiched immunoreaction, an ECL immunosensor was fabricated for sensitive determination of N-acetyl-β-d-glucosaminidase (NAG), a typical biomarker for diabetic nephropathy (DN). The detemination linear range was 0.1 pg mL(-1) to 1 ng mL(-1), and the detection limit was 0.028 pg mL(-1). The developed strategy combining the ECL self-enhanced "light-switch" molecular and DNA nanotechnology offers an effective signal amplification mean and provides ample potential for further bioanalysis and clinical study.

  8. N-Acetyl-S-(1-carbamoyl-2-hydroxy-ethyl)-L-cysteine (iso-GAMA) a further product of human metabolism of acrylamide: comparison with the simultaneously excreted other mercaptuic acids.

    Science.gov (United States)

    Hartmann, Eva C; Boettcher, Melanie I; Bolt, Hermann M; Drexler, Hans; Angerer, Jürgen

    2009-07-01

    The N-acetyl-S-(1-carbamoyl-2-hydroxy-ethyl)-L: -cysteine (iso-GAMA) could be identified as a further human metabolite of acrylamide. In this study, we report the excretion of d(3)-iso-GAMA in human urine after single oral administration of deuterium labelled acrylamide (d(3)-AA). One healthy male volunteer ingested a dose of about 1 mg d(3)-AA which is equivalent to a dose of 13 microg/kg bodyweight. Over a period of 46 h the urine was collected and the d(3)-iso-GAMA levels analysed by LC-ESI-MS/MS. The excretion of iso-GAMA begins five hours after application. It rises to a maximum concentration (c (max)) of 43 microg/l which was quantified in the urine excreted after 22 h (t (max)). The excretion pattern is parallel to that of the major oxidative metabolite N-acetyl-S-(2-carbamoyl-2-hydroxy-ethyl)-L-cysteine (GAMA). Total recovery of iso-GAMA was about 1% of the applied dose. Together with N-acetyl-S-(2-carbamoylethyl)-L: -cysteine (AAMA) and GAMA, 57% of the applied dose is eliminated as mercapturic acids. The elimination kinetics of the three mercapturic acids of AA are compared. We show that dietary doses of acrylamide (AA) cause an overload of detoxification via AAMA and lead to the formation of carcinogenic glycidamide (GA) in the human body.

  9. Evaluation of the Effects of S-Allyl-L-cysteine, S-Methyl-L-cysteine, trans-S-1-Propenyl-L-cysteine, and Their N-Acetylated and S-Oxidized Metabolites on Human CYP Activities.

    Science.gov (United States)

    Amano, Hirotaka; Kazamori, Daichi; Itoh, Kenji

    2016-01-01

    Three major organosulfur compounds of aged garlic extract, S-allyl-L-cysteine (SAC), S-methyl-L-cysteine (SMC), and trans-S-1-propenyl-L-cysteine (S1PC), were examined for their effects on the activities of five major isoforms of human CYP enzymes: CYP1A2, 2C9, 2C19, 2D6, and 3A4. The metabolite formation from probe substrates for the CYP isoforms was examined in human liver microsomes in the presence of organosulfur compounds at 0.01-1 mM by using liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Allicin, a major component of garlic, inhibited CYP1A2 and CYP3A4 activity by 21-45% at 0.03 mM. In contrast, a CYP2C9-catalyzed reaction was enhanced by up to 1.9 times in the presence of allicin at 0.003-0.3 mM. SAC, SMC, and S1PC had no effect on the activities of the five isoforms, except that S1PC inhibited CYP3A4-catalyzed midazolam 1'-hydroxylation by 31% at 1 mM. The N-acetylated metabolites of the three compounds inhibited the activities of several isoforms to a varying degree at 1 mM. N-Acetyl-S-allyl-L-cysteine and N-acetyl-S-methyl-L-cysteine inhibited the reactions catalyzed by CYP2D6 and CYP1A2, by 19 and 26%, respectively, whereas trans-N-acetyl-S-1-propenyl-L-cysteine showed weak to moderate inhibition (19-49%) of CYP1A2, 2C19, 2D6, and 3A4 activities. On the other hand, both the N-acetylated and S-oxidized metabolites of SAC, SMC, and S1PC had little effect on the reactions catalyzed by the five isoforms. These results indicated that SAC, SMC, and S1PC have little potential to cause drug-drug interaction due to CYP inhibition or activation in vivo, as judged by their minimal effects (IC50>1 mM) on the activities of five major isoforms of human CYP in vitro.

  10. MOF Acetyl Transferase Regulates Transcription and Respiration in Mitochondria.

    Science.gov (United States)

    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.

  11. Roles for glutathione transferases in antioxidant recycling.

    Science.gov (United States)

    Dixon, David P; Steel, Patrick G; Edwards, Robert

    2011-08-01

    Uniquely among the plant glutathione transferases, two classes possess a catalytic cysteine capable of performing glutathione-dependent reductions. These are the dehydroascorbate reductases (DHARs) and the lambda-class glutathione transferases (GSTLs). Using immobilized GSTLs probed with crude plant extracts we have identified flavonols as high affinity ligands and subsequently demonstrated a novel glutathione-dependent role for these enzymes in recycling oxidized quercetin. By comparing the activities of DHARs and GSTLs we now propose a unified catalytic mechanism that suggests oxidized anthocyanidins and tocopherols may be alternative polyphenolic substrates of GSTLs.

  12. Nephrotoxicity of 2-bromo-(cystein-S-yl) hydroquinone and 2-bromo-(N-acetyl-L-cystein-S-yl) hydroquinone thioethers.

    Science.gov (United States)

    Monks, T J; Jones, T W; Hill, B A; Lau, S S

    1991-11-01

    The in vivo toxicity of isomeric cystein-S-yl and N-acetylcystein-S-yl conjugates of 2-bromohydroquinone was determined in male Sprague-Dawley rats. 2-Bromo-(dicystein-S-yl)hydroquinone [2-Br-(diCYS)HQ] and 2-bromo-(di-N-acetyl-L-cystein-S-yl)hydroquinone [2-Br-(diNAC)HQ] were considerably more nephrotoxic than their corresponding monosubstituted thioethers and 2-Br-(diCYS)HQ was more nephrotoxic than 2-Br-(diNAC)HQ. 2-Br-(diCYS)HQ caused elevations in blood urea nitrogen (BUN) concentrations and increases in the urinary excretion of glucose, lactate dehydrogenase (LDH), and gamma-glutamyl transpeptidase (gamma-GT) at a dose of 25 mumol/kg (iv). In contrast, 2-Br-(diNAC)HQ caused significant elevations in BUN at 100 mumol/kg and glucosuria and enzymuria at 50 mumol/kg. 2-Br-3-(CYS)HQ and 2-Br-5&6-(CYS)HQ caused increases in the biochemical indices of nephrotoxicity at doses between 50 and 150 mumol/kg whereas 2-Br-5-(NAC)HQ and 2-Br-6-(NAC)HQ required doses of 150-200 mumol/kg to cause smaller, though significant increases in urinary glucose, gamma-GT, and LDH excretion. The histological alterations caused by each thioether were qualitatively similar; only differences in the extent of the renal proximal tubular damage were observed. The initial lesion appears to involve the cells of the medullary ray and the S3M within the outer stripe of the outer medulla. The in vivo nephrotoxicity of 2-Br-(DiCYS)HQ, 2-Br-(diNAC)HQ, and the most potent monosubstituted thioethers, 2-Br-5&6-(CYS)HQ and 2-Br-6-(NAC)HQ, was investigated further. Pretreatment of animals with aminooxyacetic acid, an inhibitor of cysteine conjugate beta-lyase (beta-lyase), had no effect on the toxicity of 2-Br-(diCYS)HQ, partially inhibited the toxicity of 2-Br-5&6-(CYS)HQ, and almost completely protected against the toxicity of both 2-Br-6-(NAC)HQ and 2-Br-(diNAC)HQ. Thus, the nephrotoxicity of 2-Br-5&6-(CYS)HQ, 2-Br-6-(NAC)HQ, and 2-Br-(diNAC)HQ may be mediated, in part, via their processing by beta

  13. The influence of N-acetyl-L-cysteine on oxidative stress and nitric oxide synthesis in stimulated macrophages treated with a mustard gas analogue

    Directory of Open Access Journals (Sweden)

    Smith Milton

    2008-06-01

    Full Text Available Abstract Background Sulphur mustard gas, 2, 2'-dichlorodiethyl sulphide (HD, is a chemical warfare agent. Both mustard gas and its monofunctional analogue, 2-chloroethyl ethyl sulphide (CEES, are alkylating agents that react with and diminish cellular thiols and are highly toxic. Previously, we reported that lipopolysaccharide (LPS significantly enhances the cytotoxicity of CEES in murine RAW 264.7 macrophages and that CEES transiently inhibits nitric oxide (NO production via suppression of inducible NO synthase (iNOS protein expression. NO generation is an important factor in wound healing. In this paper, we explored the hypotheses that LPS increases CEES toxicity by increasing oxidative stress and that treatment with N-acetyl-L-cysteine (NAC would block LPS induced oxidative stress and protect against loss of NO production. NAC stimulates glutathione (GSH synthesis and also acts directly as a free radical scavenger. The potential therapeutic use of the antibiotic, polymyxin B, was also evaluated since it binds to LPS and could thereby block the enhancement of CEES toxicity by LPS and also inhibit the secondary infections characteristic of HD/CEES wounds. Results We found that 10 mM NAC, when administered simultaneously or prior to treatment with 500 μM CEES, increased the viability of LPS stimulated macrophages. Surprisingly, NAC failed to protect LPS stimulated macrophages from CEES induced loss of NO production. Macrophages treated with both LPS and CEES show increased oxidative stress parameters (cellular thiol depletion and increased protein carbonyl levels. NAC effectively protected RAW 264.7 cells simultaneously treated with CEES and LPS from GSH loss and oxidative stress. Polymyxin B was found to partially block nitric oxide production and diminish CEES toxicity in LPS-treated macrophages. Conclusion The present study shows that oxidative stress is an important mechanism contributing to CEES toxicity in LPS stimulated macrophages and

  14. A Biodistribution and Toxicity Study of Cobalt Dichloride-N-Acetyl Cysteine in an Implantable MRI Marker for Prostate Cancer Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Frank, Steven J., E-mail: sjfrank@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Texas (United States); Johansen, Mary J. [Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Texas (United States); Martirosyan, Karen S. [Department of Physics and Astronomy, The University of Texas at Brownsville, Texas (United States); Gagea, Mihai; Van Pelt, Carolyn S.; Borne, Agatha [Department of Veterinary Medicine, Surgery, and Pathology, The University of Texas MD Anderson Cancer Center, Texas (United States); Carmazzi, Yudith; Madden, Timothy [Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Texas (United States)

    2013-03-15

    Purpose: C4, a cobalt dichloride-N-acetyl cysteine complex, is being developed as a positive-signal magnetic resonance imaging (MRI) marker to localize implanted radioactive seeds in prostate brachytherapy. We evaluated the toxicity and biodistribution of C4 in rats with the goal of simulating the systemic effects of potential leakage from C4 MRI markers within the prostate. Methods and Materials: 9-μL doses (equivalent to leakage from 120 markers in a human) of control solution (0.9% sodium chloride), 1% (proposed for clinical use), and 10% C4 solution were injected into the prostates of male Sprague-Dawley rats via laparotomy. Organ toxicity and cobalt disposition in plasma, tissues, feces, and urine were evaluated. Results: No C4-related morbidity or mortality was observed in the biodistribution arm (60 rats). Biodistribution was measurable after 10% C4 injection: cobalt was cleared rapidly from periprostatic tissue; mean concentrations in prostate were 163 μg/g and 268 μg/g at 5 and 30 minutes but were undetectable by 60 minutes. Expected dual renal-hepatic elimination was observed, with percentages of injected dose recovered in tissues of 39.0 ± 5.6% (liver), >11.8 ± 6.5% (prostate), and >5.3 ± 0.9% (kidney), with low plasma concentrations detected up to 1 hour (1.40 μg/mL at 5-60 minutes). Excretion in urine was 13.1 ± 4.6%, with 3.1 ± 0.54% recovered in feces by 24 hours. In the toxicity arm, 3 animals died in the control group and 1 each in the 1% and 10% groups from surgical or anesthesia-related complications; all others survived to scheduled termination at 14 days. No C4-related adverse clinical signs or organ toxicity were observed. Conclusion: C4-related toxicity was not observed at exposures at least 10-fold the exposure proposed for use in humans. These data demonstrating lack of systemic toxicity with dual routes of elimination in the event of in situ rupture suggest that C4 warrants further investigation as an MRI marker for prostate

  15. A novel deconvolution method for modeling UDP-N-acetyl-D-glucosamine biosynthetic pathways based on 13C mass isotopologue profiles under non-steady-state conditions

    Directory of Open Access Journals (Sweden)

    Belshoff Alex C

    2011-05-01

    Full Text Available Abstract Background Stable isotope tracing is a powerful technique for following the fate of individual atoms through metabolic pathways. Measuring isotopic enrichment in metabolites provides quantitative insights into the biosynthetic network and enables flux analysis as a function of external perturbations. NMR and mass spectrometry are the techniques of choice for global profiling of stable isotope labeling patterns in cellular metabolites. However, meaningful biochemical interpretation of the labeling data requires both quantitative analysis and complex modeling. Here, we demonstrate a novel approach that involved acquiring and modeling the timecourses of 13C isotopologue data for UDP-N-acetyl-D-glucosamine (UDP-GlcNAc synthesized from [U-13C]-glucose in human prostate cancer LnCaP-LN3 cells. UDP-GlcNAc is an activated building block for protein glycosylation, which is an important regulatory mechanism in the development of many prominent human diseases including cancer and diabetes. Results We utilized a stable isotope resolved metabolomics (SIRM approach to determine the timecourse of 13C incorporation from [U-13C]-glucose into UDP-GlcNAc in LnCaP-LN3 cells. 13C Positional isotopomers and isotopologues of UDP-GlcNAc were determined by high resolution NMR and Fourier transform-ion cyclotron resonance-mass spectrometry. A novel simulated annealing/genetic algorithm, called 'Genetic Algorithm for Isotopologues in Metabolic Systems' (GAIMS was developed to find the optimal solutions to a set of simultaneous equations that represent the isotopologue compositions, which is a mixture of isotopomer species. The best model was selected based on information theory. The output comprises the timecourse of the individual labeled species, which was deconvoluted into labeled metabolic units, namely glucose, ribose, acetyl and uracil. The performance of the algorithm was demonstrated by validating the computed fractional 13C enrichment in these subunits

  16. A multi-matrix HILIC-MS/MS method for the quantitation of endogenous small molecule neurological biomarker N-acetyl aspartic acid (NAA).

    Science.gov (United States)

    Sangaraju, Dewakar; Shahidi-Latham, Sheerin K; Burgess, Braydon L; Dean, Brian; Ding, Xiao

    2017-03-14

    A multi-matrix hydrophilic interaction liquid chromatography tandem mass spectrometric method (HILIC-MS/MS) was developed for the quantitation of N-Acetyl Aspartic acid (NAA) using stable isotope labeled internal standard, D3-NAA in various biological matrices such as human plasma, human CSF, mouse plasma, brain and spinal cord. A high throughput 96-well plate format supported liquid extraction (SLE) procedure was developed and used for sample preparation. Mass spectrometric analysis of NAA was performed using selected reaction monitoring transitions in positive electrospray ionization mode. As NAA is endogenously present, a surrogate matrix approach was used for quantitation of NAA and the method was qualified over linear calibration curve range of 0.01-10μg/mL. Intra and inter assay precision indicated by percent relative standard deviation (%RSD) was less than 7.1% for low, medium, medium high and high QCs. The accuracy of the method ranged from 92.6-107.0% of nominal concentration for within-run and between-run for the same QCs. Extraction recovery of NAA and D3-NAA was greater than 76%. Stability of NAA was established in the above biological matrices under bench top (RT, 5h), freeze thaw (-20±10°C, 3 cycles) and moues/human plasma sample collection (Wet ice, RT) conditions. HILIC-MS/MS method was then used to quantify and compare the NAA levels in human plasma and CSF of ALS patients versus control human subjects. NAA CSF levels in control human subjects (73.3±31.0ng/mL,N=10) were found to be slightly higher than ALS patients (46.1±22.6ng/mL, N=10) (P=0.04). No differences were observed in NAA plasma levels in human control subjects (49.7±13.8ng/mL,N=9) as compared to ALS patients (49.6±8.1ng/mL, N=10) (P=0.983). NAA endogenous concentrations in mouse plasma, brain and spinal cord were found to be 243.8±56.8ng/mL (N=6), 1029.8±115.2μg/g tissue weight (N=5) and 487.6±178.4μg/g tissue weight (N=5) respectively.

  17. Dual effects of N-acetyl-L-cysteine dependent on NQO1 activity: Suppressive or promotive of 9,10-phenanthrenequinone-induced toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Toyooka, Tatsushi; Shinmen, Takuya [Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka (Japan); Aarts, Jac M.M.J.G. [Division of Toxicology, Wageningen University, Wageningen (Netherlands); Ibuki, Yuko, E-mail: ibuki@u-shizuoka-ken.ac.jp [Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka (Japan)

    2012-11-01

    A typical antioxidant, N-acetyl-L-cysteine (NAC) generally protects cells from oxidative damage induced by reactive oxygen species (ROS). 9,10-Phenanthrenequinone (9,10-PQ), a major quinone in diesel exhaust particles, produces ROS in redox cycling following two-electron reduction by NAD(P)H:quinone oxidoreductase 1 (NQO1), which has been considered as a cause of its cyto- and genotoxicity. In this study, we show that NAC unexpectedly augments the toxicity of 9,10-PQ in cells with low NQO1 activity. In four human skin cell lines, the expression and the activity of NQO1 were lower than in human adenocarcinoma cell lines, A549 and MCF7. In the skin cells, the cytotoxicity of 9,10-PQ was significantly enhanced by addition of NAC. The formation of DNA double strand breaks accompanying phosphorylation of histone H2AX, was also remarkably augmented. On the other hand, the cyto- and genotoxicity were suppressed by addition of NAC in the adenocarcinoma cells. Two contrasting experiments: overexpression of NQO1 in CHO-K1 cells which originally expressed low NQO1 levels, and knock‐down of NQO1 in the adenocarcinoma cell line A549 by transfection of RNAi, also showed that NAC suppressed 9,10-PQ-induced toxicity in cell lines expressing high NQO1 activity and enhanced it in cell lines with low NQO1 activity. The results suggested that dual effects of NAC on the cyto- and genotoxicity of 9,10-PQ were dependent on tissue-specific NQO1 activity. -- Highlights: ► NAC augmented the cytotoxicity of 9,10-PQ in skin cell lines. ► 9,10-PQ-induced DSBs accompanying γ-H2AX were also augmented by NAC. ► NAC suppressed the cyto- and genotoxicity of 9,10-PQ in adenocarcinoma cell lines. ► The dual effects of NAC on toxicity of 9,10-PQ were dependent on NQO1 activity.

  18. N-acetyl-S-(N,N-diethylcarbamoyl) cysteine in rat nucleus accumbens, medial prefrontal cortex, and in rat and human plasma after disulfiram administration.

    Science.gov (United States)

    Winefield, Robert D; Heemskerk, Anthonius A M; Kaul, Swetha; Williams, Todd D; Caspers, Michael J; Prisinzano, Thomas E; McCance-Katz, Elinore F; Lunte, Craig E; Faiman, Morris D

    2015-03-25

    Disulfiram (DSF), a treatment for alcohol use disorders, has shown some clinical effectiveness in treating addiction to cocaine, nicotine, and pathological gambling. The mechanism of action of DSF for treating these addictions is unclear but it is unlikely to involve the inhibition of liver aldehyde dehydrogenase (ALDH2). DSF is a pro-drug and forms a number of metabolites, one of which is N-acetyl-S-(N,N-diethylcarbamoyl) cysteine (DETC-NAC). Here we describe a LCMS/MS method on a QQQ type instrument to quantify DETC-NAC in plasma and intracellular fluid from mammalian brain. An internal standard, the N,N-di-isopropylcarbamoyl homolog (MIM: 291>128) is easily separable from DETC-NAC (MIM: 263>100) on C18 RP media with a methanol gradient. The method's linear range is 0.5-500 nM from plasma and dialysate salt solution with all precisions better than 10% RSD. DETC-NAC and internal standards were recovered at better than 95% from all matrices, perchloric acid precipitation (plasma) or formic acid addition (salt) and is stable in plasma or salt at low pH for up to 24 h. Stability is observed through three freeze-thaw cycles per day for 7 days. No HPLC peak area matrix effect was greater than 10%. A human plasma sample from a prior analysis for S-(N,N-diethylcarbamoyl) glutathione (CARB) was found to have DETC NAC as well. In other human plasma samples from 62.5 mg/d and 250 mg/d dosing, CARB concentration peaks at 0.3 and 4 nM at 3 h followed by DETC-NAC peaks of 11 and 70 nM 2 h later. Employing microdialysis sampling, DETC-NAC levels in the nucleus accumbens (NAc), medial prefrontal cortex (mPFC), and plasma of rats treated with DSF reached 1.1, 2.5 and 80 nM at 6h. The correlation between the appearance and long duration of DETC-NAC concentration in rat brain and the persistence of DSF-induced changes in neurotransmitters observed by Faiman et al. (Neuropharmacology, 2013, 75C, 95-105) is discussed.

  19. Plant glutathione transferase-mediated stress tolerance

    NARCIS (Netherlands)

    Nianiou-Obeidat, Irini; Madesis, Panagiotis; Kissoudis, Christos; Voulgari, Georgia; Chronopoulou, Evangelia; Tsaftaris, Athanasios; Labrou, Nikolaos E.

    2017-01-01

    Plant glutathione transferases (EC 2.5.1.18, GSTs) are an ancient, multimember and diverse enzyme class. Plant GSTs have diverse roles in plant development, endogenous metabolism, stress tolerance, and xenobiotic detoxification. Their study embodies both fundamental aspects and agricultural

  20. [Structure and functions of glutathione transferases].

    Science.gov (United States)

    Fedets, O M

    2014-01-01

    Data about classification, nomenclature, structure, substrate specificity and role of many glutathione transferase's isoenzymes in cell functions have been summarised. The enzyme has been discovered more than 50 years ago. This family of proteins is updated continuously. It has very different composition and will have demand for system analysis for many years.

  1. Overexpression of GalNAc-transferase GalNAc-T3 promotes pancreatic cancer cell growth.

    Science.gov (United States)

    Taniuchi, K; Cerny, R L; Tanouchi, A; Kohno, K; Kotani, N; Honke, K; Saibara, T; Hollingsworth, M A

    2011-12-01

    O-linked glycans of secreted and membrane-bound proteins have an important role in the pathogenesis of pancreatic cancer by modulating immune responses, inflammation and tumorigenesis. A critical aspect of O-glycosylation, the position at which proteins are glycosylated with N-acetyl-galactosamine on serine and threonine residues, is regulated by the substrate specificity of UDP-GalNAc:polypeptide N-acetylgalactosaminyl-transferases (GalNAc-Ts). Thus, GalNAc-Ts regulate the first committed step in O-glycosylated protein biosynthesis, determine sites of O-glycosylation on proteins and are important for understanding normal and carcinoma-associated O-glycosylation. We have found that one of these enzymes, GalNAc-T3, is overexpressed in human pancreatic cancer tissues and suppression of GalNAc-T3 significantly attenuates the growth of pancreatic cancer cells in vitro and in vivo. In addition, suppression of GalNAc-T3 induces apoptosis of pancreatic cancer cells. Our results indicate that GalNAc-T3 is likely involved in pancreatic carcinogenesis. Modification of cellular glycosylation occurs in nearly all types of cancer as a result of alterations in the expression levels of glycosyltransferases. We report guanine the nucleotide-binding protein, α-transducing activity polypeptide-1 (GNAT1) as a possible substrate protein of GalNAc-T3. GalNAc-T3 is associated with O-glycosylation of GNAT1 and affects the subcellular distribution of GNAT1. Knocking down endogenous GNAT1 significantly suppresses the growth/survival of PDAC cells. Our results imply that GalNAc-T3 contributes to the function of O-glycosylated proteins and thereby affects the growth and survival of pancreatic cancer cells. Thus, substrate proteins of GalNAc-T3 should serve as important therapeutic targets for pancreatic cancers.

  2. Resistance to acetaminophen-induced hepatotoxicity in glutathione S-transferase Mu 1-null mice.

    Science.gov (United States)

    Arakawa, Shingo; Maejima, Takanori; Fujimoto, Kazunori; Yamaguchi, Takashi; Yagi, Masae; Sugiura, Tomomi; Atsumi, Ryo; Yamazoe, Yasushi

    2012-01-01

    We investigated the role of glutathione S-transferases Mu 1 (GSTM1) in acetaminophen (APAP)-induced hepatotoxicity using Gstm1-null mice. A single oral administration of APAP resulted in a marked increase in plasma alanine aminotransferase accompanied by hepatocyte necrosis 24 hr after administration in wild-type mice, but its magnitude was unexpectedly attenuated in Gstm1-null mice. Therefore, it is suggested that Gstm1-null mice are resistant to APAP-induced hepatotoxicity. To examine the mechanism of this resistance in Gstm1-null mice, we measured phosphorylation of c-jun N-terminal kinase (JNK), which mediates the signal of APAP-induced hepatocyte necrosis, by Western blot analysis 2 and 6 hr after APAP administration. A marked increase in phosphorylated JNK was observed in wild-type mice, but the increase was markedly suppressed in Gstm1-null mice. Therefore, it is suggested that suppressed phosphorylation of JNK may be a main mechanism of the resistance to APAP-induced hepatotoxicity in Gstm1-null mice, although other possibilities of the mechanism cannot be eliminated. Additionally, phosphorylation of glycogen synthase kinase-3β and mitogen-activated protein kinase kinase 4, which are upstream kinases of JNK in APAP-induced hepatotoxicity, were also suppressed in Gstm1-null mice. A decrease in liver total glutathione 2 hr after APAP administration, which is an indicator for exposure to N-acetyl-p-benzoquinoneimine, the reactive metabolite of APAP, were similar in wild-type and Gstm1-null mice. In conclusion, Gstm1-null mice are considered to be resistant to APAP-induced hepatotoxicity perhaps by the suppression of JNK phosphorylation. This study indicates the novel role of GSTM1 as a factor mediating the cellular signal for APAP-induced hepatotoxicity.

  3. 21 CFR 862.1535 - Ornithine carbamyl transferase test system.

    Science.gov (United States)

    2010-04-01

    ... carbamyl transferase (OCT) in serum. Ornithine carbamyl transferase measurements are used in the diagnosis and treatment of liver diseases, such as infectious hepatitis, acute cholecystitis (inflammation of the gall bladder), cirrhosis, and liver metastases. (b) Classification. Class I (general controls...

  4. Glutathione transferases as targets for cancer therapy.

    Science.gov (United States)

    Ruzza, Paolo; Rosato, Antonio; Rossi, Carlo Riccardo; Floreani, Maura; Quintieri, Luigi

    2009-09-01

    Besides catalyzing the inactivation of various electrophile-producing anticancer agents via conjugation to the tripeptide glutathione, some cytosolic proteins belonging to the glutathione transferase (formerly glutatione-S-transferase; GST) superfamily are emerging as negative modulators of stress/drug-induced cell apoptosis through the interaction with specific signaling kinases. In addition, several data link the overexpression of some GSTs, in particular GSTP1-1, to both natural and acquired resistance to various structurally unrelated anticancer drugs. Tumor overexpression of these proteins has provided a rationale for the search of GST inhibitors and GST-activated cytotoxic prodrugs. In the present review we discuss the current structural and pharmacological knowledge of both types of GST-targeting compounds.

  5. Purification and characterization of the Oligosaccharyl transferase

    Energy Technology Data Exchange (ETDEWEB)

    Kapoor, T.M.

    1990-11-01

    Oligosaccharyl transferase was characterized to be a glycoprotein with at least one saccharide unit that had a D-manno or D- glucopyranose configuration with unmodified hydroxy groups at C-3, C-4 and C-6, using a Concanavalin A affinity column. This afforded a 100 fold increase in the transferase purity in the solubilized microsomal sample and also removed over 90% of the microsomal proteins (the cytosolic ones being removed before solubilization). The detergent, N,N-Dimethyldodecylamine N-oxide (LDAO) was used for solubilization and it yielded a system compatible with the assay and the purification steps. An efficient method for detergent extraction without dilution of sample or protein precipitation was also developed.

  6. Local interactions in peptides. 1H-1H, 13C-H coupling constants and calculations for the conformational analysis of N-acetyl-N'-methylamides of aliphatic amino acids.

    Science.gov (United States)

    Fermandjian, S; Sakarellos, C; Aumelas, A; Toma, F; Gresh, N

    1990-05-01

    We report the results of a joint NMR and theoretical investigation devoted to the conformational properties of N-acetyl-N'-methylamides of aliphatic amino acids with side chains of increasing bulkiness: Gly, Ala, Leu, Ile, and tert.Leu. In this series, determination of the coupling constants 3JHNC alpha H together with the coupling constants 3JC'NC alpha H (thanks to specific carbon-13 labeling of the N-acetyl carbonyl group) led to the derivation of alternative A, B, and C parameters in a Karplus-type relation expressing the dependence of 3JC'NC alpha H upon the phi dihedral angle. The value of the latter is found to increase regularly following the increase of the side-chain bulkiness. The theoretical conformational analysis is performed by applying the SIBFA procedure, which uses empirical formulas based on ab initio SCF computations. The conformational energy maps illustrate the progressive distortion of the backbone conformation incurred in the series Gly to tert.Leu. Theoretical values computed for 3JHNC alpha H and 3JC'NC alpha H are found to be in a good quantitative agreement with the experimental ones.

  7. Structure of N-acetyl-[beta]-D-glucosaminidase (GcnA) from the Endocarditis Pathogen Streptococcus gordonii and its Complex with the Mechanism-based Inhibitor NAG-thiazoline

    Energy Technology Data Exchange (ETDEWEB)

    Langley, David B.; Harty, Derek W.S.; Jacques, Nicholas A.; Hunter, Neil; Guss, J. Mitchell; Collyer, Charles A. (Sydney); (Westmead)

    2008-09-17

    The crystal structure of GcnA, an N-acetyl-{beta}-D-glucosaminidase from Streptococcus gordonii, was solved by multiple wavelength anomalous dispersion phasing using crystals of selenomethionine-substituted protein. GcnA is a homodimer with subunits each comprised of three domains. The structure of the C-terminal {alpha}-helical domain has not been observed previously and forms a large dimerization interface. The fold of the N-terminal domain is observed in all structurally related glycosidases although its function is unknown. The central domain has a canonical ({beta}/{alpha}){sub 8} TIM-barrel fold which harbours the active site. The primary sequence and structure of this central domain identifies the enzyme as a family 20 glycosidase. Key residues implicated in catalysis have different conformations in two different crystal forms, which probably represent active and inactive conformations of the enzyme. The catalytic mechanism for this class of glycoside hydrolase, where the substrate rather than the enzyme provides the cleavage-inducing nucleophile, has been confirmed by the structure of GcnA complexed with a putative reaction intermediate analogue, N-acetyl-{beta}-D-glucosamine-thiazoline. The catalytic mechanism is discussed in light of these and other family 20 structures.

  8. SIKLODEKSTRIN GLIKOSIL TRANSFERASE DAN PEMANFAATANNYA DALAM INDUSTRI [Cyclodextrin Glycosyl Transferase and its application in industries

    Directory of Open Access Journals (Sweden)

    Budiasih Wahyuntari

    2005-12-01

    Full Text Available Cyclodextrin glycosyl transferase (CGT-ase is mainly produced by Bacilli. Systematical name of the enzyme is E.C. 2.4.1.19 a-1,4 glucan-4-glycosyl transferase. The enzyme catalyzes hydrolysis of starch intramolecular, and intermolecular transglycosylation of a-1,4, glucan chains. Cyclodextrins are a-1,4 linked cyclic oligosaccharides resulting from enzymatic degradation of starch by cyclodextrin glycosyl transferase through untramolecular transglycosylation. The major cyclodextrins are made up of 6, 7 and 8 glucopyranose units which are known as a-, b-, and y-cyclodextrin. All CGT-ase catalyze three kinds of cyclodextrins, the proportion of the cyclodextrins depends on the enzyme source and reaction conditions. The intermolecular transglycosylation ability of the enzyme has been applied in transfering glycosyl residues into suitable acceptor. Transglycosylation by the enzymes have been tested to improve solubility of some flavonoids and to favor precipitation ci some glycosides.

  9. Changes of cerebral blood flow in rats with acute cerebral ischemia and the effect of nitric oxide donor S-nitroso-N-acetyl-penicillamine

    Institute of Scientific and Technical Information of China (English)

    Feng Gao; Zhiqiang Yi; Guijun Lin

    2006-01-01

    BACKGROUND: Previous studies show that nitric oxide donor can increase cerebral blood flow and improve the function of neurons in cerebral ischemia, but the change does not happen in all the models of cerebral ischemia. OBJECTIVE: To observe the effects of nitric oxide donor S-nitroso-N-acetyl-penicillamine (SNAP) on the cerebral blood flow, cyclic guanosine monophosphate (cGMP) content in cerebral cortex, infarct volume and blood pressure in acute ischemic rat brain.DESIGN: A randomized and control animal experiment. SETTING: Department of Neurosurgery, Aerospace Central Hospital, Peking University. MATERIALS: Twenty-eight male Wistar rats of SPF grade, weighing 250-300 g, aged 10-12 weeks were randomly divided into control group (n =14) and SNAP-treated group (n =14). SNAP (5 mg/bottle) was provided by Beijing Chemical Reagent Company. Laser Doppler Flowmeter (FLO C1; Omegawave Inc., Tokyo, Japan) and immunoassay kit (Amersham Pharmacia Biotech, UK) were applied.METHODS: ① Model establishment: In the control group, models of cerebral ischemia were induced by ligating right common, internal and external carotid arteries; In the SNAP-treated group, models of cerebral ischemia were induced by ligating right common and external carotid arteries, followed by occluding middle cerebral artery and ligating internal carotid artery. ② Administration: In the SNAP-treated group, SNAP (100 μg/kg) was intravenously infused within 2 minutes, whereas in the control group, phosphate buffered saline (PBS, 1 mL) was intravenously infused (0.5 mL per minute). Six rats were used to measure the volume of cerebral infarction, and the other 8 rats were used to determine other indexes in each group respectively. ③ Determination of indexes: Regional cerebral blood flow (rCBF) was continuously measured by laser-Doppler flowmetry in the ischemic penumbra and contralateral cortex under the continuous monitoring of blood pressure, cGMP concentrations in brain tissue were determined

  10. L-cysteine, N-acetyl-L-cysteine, and glutathione protect xenopus laevis embryos against acrylamide-induced malformations and mortality in the frog embryo teratogenesis assay (FETAX)

    Science.gov (United States)

    Dietary acrylamide is largely derived from heat-induced reactions between the amino group of the free amino acid asparagine and carbonyl groups of glucose and fructose during heat processing (baking, frying) of plant-derived foods such as potato fries and cereals. After consumption, acrylamide is a...

  11. Glutathione S-transferases in pediatric cancer

    Directory of Open Access Journals (Sweden)

    Wen eLuo

    2011-10-01

    Full Text Available The glutathione S-transferases (GSTs are a family of ubiquitously-expressed polymorphic enzymes important for detoxifying endogenous and exogenous compounds. In addition to their classic activity of detoxification by conjugation of compounds with glutathione, many other functions are now found to be associated with GSTs. The associations between GST polymorphisms/functions and human disease susceptibility or treatment outcome, mostly in adults, have been extensively studied and reviewed. This mini review focuses on studies related to GST epidemiology and functions related to pediatric cancer. Opportunities to exploit GST in pediatric cancer therapy are also discussed.

  12. Conformational Dynamics and Exchange Kinetics of N-Formyl and N-Acetyl Groups Substituting 3-Amino-3,6-dideoxy-α-d-galactopyranose, a Sugar Found in Bacterial O-Antigen Polysaccharides.

    Science.gov (United States)

    Engström, Olof; Mobarak, Hani; Ståhle, Jonas; Widmalm, Göran

    2017-10-04

    Three dimensional shape and conformation of carbohydrates are important factors in molecular recognition events and the N-acetyl group of a monosaccharide residue can function as a conformational gatekeeper whereby it influences the overall shape of the oligosaccharide. NMR spectroscopy and quantum mechanics (QM) calculations are used herein to investigate both the conformational preferences and the dynamic behavior of N-acetyl and N-formyl substituents of 3-amino-3,6-dideoxy-α-d-galactopyranose, a sugar and substitution pattern found in bacterial O-antigen polysaccharides. QM calculations suggest that the amide oxygen can be involved in hydrogen bonding with the axial OH4 group primarily but also with the equatorial OH2 group. However, an NMR J coupling analysis indicates that the θ1 torsion angle, adjacent to the sugar ring, prefers an ap conformation where conformations formyl-substituted compound (4)JHH coupling constants to the exo-cyclic group were detected and analyzed. A van't Hoff analysis revealed that the trans conformation at the amide bond is favored by ΔG° ≈ - 0.8 kcal·mol(-1) in the formyl-containing compound and with ΔG° ≈ - 2.5 kcal·mol(-1) when the N-acetyl group is the substituent. In both cases the enthalpic term dominates to the free energy, irrespective of water or DMSO as solvent, with only a small contribution from the entropic term. The cis-trans isomerization of the θ2 torsion angle, centered at the amide bond, was also investigated by employing (1)H NMR line shape analysis and (13)C NMR saturation transfer experiments. The extracted transition rate constants were utilized to calculate transition energy barriers that were found to be about 20 kcal·mol(-1) in both DMSO-d6 and D2O. Enthalpy had a higher contribution to the energy barriers in DMSO-d6 compared to in D2O, where entropy compensated for the loss of enthalpy.

  13. Antibodies with thiol-S-transferase activity

    Energy Technology Data Exchange (ETDEWEB)

    Fan, E.; Oei, Yoko; Sweet, E.; Uno, Tetsuo; Schultz, P.G. [Univ. of California, Berkeley, CA (United States)

    1996-06-12

    A major detoxification pathway used by aerobic organisms involves the conjugation of the tripeptide glutathione (GSH) to the electrophilic center of toxic substances. This reaction is catalyzed by a class of enzymes referred to as the glutathione S-transferases (GST) (EC 2.5.1.18). These enzymes activate the cysteine thiol group of GSH for nucleophilic addition to a variety of substrates, including aryl halides, {alpha}{beta}-unsaturated aldehydes and ketones, and epoxides. Despite the availability of X-ray crystal structures, the mechanism whereby glutathione transferases catalyze these addition reactions remains unclear. In order to gain a greater understanding of this important biological transformation, as well as to generate new detoxification catalysts, we have asked whether antibodies can be generated that catalyze similar nucleophilic addition reactions. Our initial efforts focused on the addition reaction of thiol nucleophiles to the nitro-substituted styrene derivative 1. The ratio of k{sub cat}/K{sub m} reported for the reaction of the isozyme 4-4` of rat liver GST with the good substance, 1-chloro-2,4-dinitrobenzene, is approximately 10{sup 4} M{sup -1} s{sup -1} compared to a calculated pseudo-first-order rate constant for the uncatalyzed reaction of approximately 3 x 10{sup -2} s{sup -1} (60 mM GSH, pH = 80). These comparisons suggest that with further improvements in hapten design, catalytic antibodies may prove a good source of detoxification catalysts. 19 refs., 1 fig.

  14. One-Step Synthesis of High-Quality Water-Soluble CdSe Quantum Dots Capped by N-Acetyl-L-cysteine via Hydrothermal Method and Their Characterization

    Directory of Open Access Journals (Sweden)

    Chunjin Wei

    2015-01-01

    Full Text Available Novel water-soluble CdSe quantum dots (QDs have been prepared with N-acetyl-L-cysteine as new stabilizer through a one-step hydrothermal route. The influence of experimental conditions, including reaction time, molar ratio of reactants, and pH value, on the luminescent properties of the obtained CdSe QDs has been systematically investigated. The characterization of as-prepared QDs was carried out through different methods. In particular, we realized qualitative and semiquantitative studies on CdSe QDs through X-ray photoelectron spectroscopy and electron diffraction spectroscopy. The results show that the as-prepared CdSe QDs exhibit a high quantum yield (up to 26.7%, high stability, and monodispersity and might be widely used in biochemical detection and biochemical research.

  15. D-Alanylation of Teichoic Acids and Loss of Poly-N-Acetyl Glucosamine in Staphylococcus aureus during Exponential Growth Phase Enhance IL-12 Production in Murine Dendritic Cells

    DEFF Research Database (Denmark)

    Lund, Lisbeth Drozd; Ingmer, Hanne; Frokiaer, Hanne

    2016-01-01

    Staphylococcus aureus is a major human pathogen that has evolved very efficient immune evading strategies leading to persistent colonization. During different stages of growth, S. aureus express various surface molecules, which may affect the immune stimulating properties, but very little is known...... about their role in immune stimulation and evasion. Depending on the growth phase, S. aureus may affect antigen presenting cells differently. Here, the impact of growth phases and the surface molecules lipoteichoic acid, peptidoglycan and poly-N-acetyl glucosamine on the induction of IL-12 imperative...... for an efficient clearance of S. aureus was studied in dendritic cells (DCs). Exponential phase (EP) S. aureus was superior to stationary phase (SP) bacteria in induction of IL-12, which required actin-mediated endocytosis and endosomal acidification. Moreover, addition of staphylococcal cell wall derived...

  16. Effect of 16.16 dimethyl prostaglandin E2, N-acetyl-cysteine and the proton pump inhibitor BY 831-78 on hydrogen peroxide-induced mucosal damage in the rat stomach.

    Science.gov (United States)

    Schürer-Maly, C C; Haussner, V; Halter, F

    1990-01-01

    Reactive oxygen species are noxious to gastrointestinal mucosa and contribute to a variety of gastrointestinal diseases. We examined whether 16.16 dimethyl prostaglandin E2 (PG) is protective against the oxidizing action of 6% H2O2 causing gross hemorrhagic lesions in rat gastric mucosa. Male Wistar rats were treated with PG, 0.005-5 micrograms/kg, either intragastrically (i.g.) or subcutaneously, 30 min prior to i.g. administration of 6% H2O2, 0.5 ml/100 g. Further animals received 25 mg of the mucus dissolvent N-acetyl-cystein (NAC) following oral PG treatment or 30 mumol/kg of the H+K(+)-ATPase inhibitor BY 831-78 (BY), 4 h before onset of the experiments. Volume, pH and beta-N-acetyl-glucosaminidase and lactate dehydrogenase as parameters of cell damage were determined in the gastric juice. i.g. PG treatment achieved 60 and 55% reduction of the mucosal lesions in doses between 5 and 0.05 micrograms/kg, respectively. i.p. PG administration was effective in all doses tested. Gastric juice volume was only slightly and enzymes were not significantly affected by PG treatment. NAC did not diminish PG efficacy or aggravate mucosal lesions. Gastric acid suppression did not increase PG-induced protection but was strongly protective by itself, reducing damage by 75%. Low-dose PG treatment achieves an effective protection against oxidative damage in gastric mucosa, which is not the result of dilution or enhanced mucus production.

  17. D-Alanylation of Teichoic Acids and Loss of Poly-N-Acetyl Glucosamine in Staphylococcus aureus during Exponential Growth Phase Enhance IL-12 Production in Murine Dendritic Cells.

    Science.gov (United States)

    Lund, Lisbeth Drozd; Ingmer, Hanne; Frøkiær, Hanne

    2016-01-01

    Staphylococcus aureus is a major human pathogen that has evolved very efficient immune evading strategies leading to persistent colonization. During different stages of growth, S. aureus express various surface molecules, which may affect the immune stimulating properties, but very little is known about their role in immune stimulation and evasion. Depending on the growth phase, S. aureus may affect antigen presenting cells differently. Here, the impact of growth phases and the surface molecules lipoteichoic acid, peptidoglycan and poly-N-acetyl glucosamine on the induction of IL-12 imperative for an efficient clearance of S. aureus was studied in dendritic cells (DCs). Exponential phase (EP) S. aureus was superior to stationary phase (SP) bacteria in induction of IL-12, which required actin-mediated endocytosis and endosomal acidification. Moreover, addition of staphylococcal cell wall derived peptidoglycan to EP S. aureus stimulated cells increased bacterial uptake but abrogated IL-12 induction, while addition of lipoteichoic acid increased IL-12 production but had no effect on the bacterial uptake. Depletion of the capability to produce poly-N-acetyl glucosamine increased the IL-12 inducing activity of EP bacteria. Furthermore, the mutant dltA unable to produce D-alanylated teichoic acids failed to induce IL-12 but like peptidoglycan and the toll-like receptor (TLR) ligands LPS and Pam3CSK4 the mutant stimulated increased macropinocytosis. In conclusion, the IL-12 response by DCs against S. aureus is highly growth phase dependent, relies on cell wall D-alanylation, endocytosis and subsequent endosomal degradation, and is abrogated by receptor induced macropinocytosis.

  18. The effects of organic solvents on the efficiency and regioselectivity of N-acetyl-lactosamine synthesis, using the β-galactosidase from Bacillus circulans in hydro-organic media.

    Science.gov (United States)

    Bridiau, Nicolas; Issaoui, Neyssène; Maugard, Thierry

    2010-01-01

    The enzymatic synthesis of N-acetyl-lactosamine (LacNAc) by the transgalactosylation of N-acetyl-D-glucosamine (GlcNAc), catalyzed by the β-galactosidase from Bacillus circulans (BcβGal), was studied in hydro-organic media, starting from o-nitrophenyl-β-D-galactopyranoside (oNPG) as a galactosyl donor. Thermal stability and synthesis activity of BcβGal were shown to depend on the organic solvent polarity, characterized by its Log P value. BcβGal was thus most stable in 10% (v/v) t-BuOH, an organic solvent found to have a stabilizing and/or weakly denaturing property, which was confirmed for high t-BuOH concentrations. In the same manner, the optimal synthesis yield increased as the Log P value of the organic solvent increased. The best results were obtained for reactions carried out in 10% (v/v) pyridine or 2-methyl-2-butanol, which gave 47% GlcNAc transgalactosylation yield based on starting oNPG, of which 23% (11 mM; 4.3 g/L) consisted in LacNAc synthesis. Furthermore, it was also established that both the GlcNAc transgalactosylation yield and the enzyme regioselectivity depended on the percentage of organic solvent used, the optimal percentage varying from 10 to 40% (v/v), depending on the solvent. This phenomenon was found to correlate mainly with the thermodynamic activity of water (a(w)) in the aqueous organic solvent mixture, which was found to be optimal when close to 0.96, whatever the organic solvent used. Finally, this study highlighted the fact that the regioselectivity of BcβGal for 1-4 linkage formation could be advantageously managed by controlling the a(w) parameter. © 2010 American Institute of Chemical Engineers

  19. Glutathione S-transferases as risk factors in prostate cancer

    DEFF Research Database (Denmark)

    Autrup, Judith; Thomassen, L.H.; Olsen, J.H.

    1999-01-01

    Glutathione S-transferases are enzymes involved in the metabolism of carcinogens and in the defence against reactive oxygen species. Genetic polymorphisms have been detected in glutathione S-transferases M1, T1 and P1, and some of these polymorphisms have been associated with an increased risk of...

  20. Assembling consumption

    DEFF Research Database (Denmark)

    Assembling Consumption marks a definitive step in the institutionalisation of qualitative business research. By gathering leading scholars and educators who study markets, marketing and consumption through the lenses of philosophy, sociology and anthropology, this book clarifies and applies...... societies. This is an essential reading for both seasoned scholars and advanced students of markets, economies and social forms of consumption....

  1. Glyceryl trinitrate metabolism in the quail embryo by the glutathione S-transferases leads to a perturbation in redox status and embryotoxicity.

    Science.gov (United States)

    Bardai, Ghalib K; Hales, Barbara F; Sunahara, Geoffrey I

    2013-07-01

    Exposure of stage 9 quail (Coturnix coturnix japonica) embryos to glyceryl trinitrate (GTN) induces malformations that were associated in previous studies with an increase in protein nitration. Increased nitration suggests metabolism of GTN by the embryo. The goals of this study were to characterize the enzymes and co-factors required for GTN metabolism by quail embryos, and to determine the effects of in ovo treatment with N-acetyl cysteine (NAC), a precursor of glutathione (GSH), on GTN embryotoxicity. GTN treatment of quail embryos resulted in an increase in nitrite, a decrease in total GSH, and an increase in the ratio of NADP(+)/NADPH, indicating that redox balance may be compromised in exposed embryos. Glutathione S-transferases (GSTs; EC 2.5.1.18) purified from the whole embryo (K(m) 0.84 mM; V(max) 36 μM/min) and the embryonic eye (K(m) 0.20 mM; V(max) 30 μM/min) had GTN-metabolizing activity (1436 and 34 nmol/min/mg, respectively); the addition of ethacrynic acid, an inhibitor of GST activity, decreased GTN metabolism. Peptide sequencing of the GST isozymes indicated that alpha- or mu-type GSTs in the embryo and embryonic eye had GTN metabolizing activity. NAC co-treatment partially protected against the effects of GTN exposure. Thus, GTN denitration by quail embryo GSTs may represent a key initial step in the developmental toxicity of GTN.

  2. No change in N-acetyl aspartate in first episode of moderate depression after antidepressant treatment: 1H magnetic spectroscopy study of left amygdala and left dorsolateral prefrontal cortex

    Directory of Open Access Journals (Sweden)

    Bajs Janović M

    2014-09-01

    Full Text Available Maja Bajs Janović,1,3 Petra Kalember,2 Špiro Janović,1,3 Pero Hrabač,2 Petra Folnegović Grošić,1 Vladimir Grošić,4 Marko Radoš,5 Neven Henigsberg2,61University Department of Psychiatry, Clinical Hospital Center Zagreb, Zagreb, 2Polyclinic Neuron, Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Zagreb, 3University North, Varaždin, 4Psychiatric Hospital Sveti Ivan, Zagreb, 5University Department of Radiology, Clinical Hospital Center Zagreb, Zagreb, 6Psychiatric Clinic Vrapče, Zagreb, CroatiaBackground: The role of brain metabolites as biological correlates of the intensity, symptoms, and course of major depression has not been determined. It has also been inconclusive whether the change in brain metabolites, measured with proton magnetic spectroscopy, could be correlated with the treatment outcome. Methods: Proton magnetic spectroscopy was performed in 29 participants with a first episode of moderate depression occurring in the left dorsolateral prefrontal cortex and left amygdala at baseline and after 8 weeks of antidepressant treatment with escitalopram. The Montgomery-Asberg Depression Rating Scale, the Hamilton Rating Scale for Depression, and the Beck Depression Inventory were used to assess the intensity of depression at baseline and at the endpoint of the study. At endpoint, the participants were identified as responders (n=17 or nonresponders (n=12 to the antidepressant therapy. Results: There was no significant change in the N-acetyl aspartate/creatine ratio (NAA/Cr after treatment with antidepressant medication. The baseline and endpoint NAA/Cr ratios were not significantly different between the responder and nonresponder groups. The correlation between NAA/Cr and changes in the scores of clinical scales were not significant in either group. Conclusion: This study could not confirm any significant changes in NAA after antidepressant treatment in the first episode of moderate depression, or in

  3. In-source formation of N-acetyl-p-benzoquinone imine (NAPQI), the putatively toxic acetaminophen (paracetamol) metabolite, after derivatization with pentafluorobenzyl bromide and GC-ECNICI-MS analysis.

    Science.gov (United States)

    Tsikas, Dimitrios; Trettin, Arne; Zörner, Alexander A; Gutzki, Frank-Mathias

    2011-05-15

    Pentafluorobenzyl (PFB) bromide (PFB-Br) is a versatile derivatization reagent for numerous classes of compounds. Under electron-capture negative-ion chemical ionization (ECNICI) conditions PFB derivatives of acidic compounds readily and abundantly ionize to produce intense anions due to [M-PFB](-). In the present article we investigated the PFB-Br derivatization of unlabelled acetaminophen (N-acetyl-p-aminophenol, NAPAP-d(0); paracetamol; MW 151) and tetradeuterated acetaminophen (NAPAP-d(4); MW 155) in anhydrous acetonitrile and their GC-ECNICI-MS behavior using methane as the buffer gas. In addition to the expected anions [M-PFB](-) at m/z 150 from NAPAP-d(0) and m/z 154 from NAPAP-d(4), we observed highly reproducibly almost equally intense anions at m/z 149 and m/z 153, respectively. Selected ion monitoring of these ions is suitable for specific and sensitive quantification of acetaminophen in human plasma and urine. Detailed investigations suggest in-source formation of N-acetyl-p-benzoquinone imine (NAPQI; MW 149), the putatively toxic acetaminophen metabolite, from the PFB ether derivative of NAPAP. GC-ECNICI-MS of non-derivatized NAPAP did not produce NAPQI. The peak area ratio of m/z 149 to m/z 150 and of m/z 153 to m/z 154 decreased with increasing ion-source temperature in the range 100-250°C. Most likely, NAPQI formed in the ion-source captures secondary electrons to become negatively charged (i.e., [NAPQI](-)) and thus detectable. Formation of NAPQI was not observed under electron ionization (EI) conditions, i.e., by GC-EI-MS, from derivatized and non-derivatized NAPAP. NAPQI was not detectable in flow injection analysis LC-MS of native NAPAP in positive electrospray ionization (ESI) mode, whereas in negative ESI mode low extent NAPQI formation was observed (ion-sources of mass spectrometers may form intermediates that are produced from activated drugs in enzyme-catalyzed reactions.

  4. Evaluation of the Lactate-to-N-Acetyl-aspartate Ratio Defined With Magnetic Resonance Spectroscopic Imaging Before Radiation Therapy as a New Predictive Marker of the Site of Relapse in Patients With Glioblastoma Multiforme

    Energy Technology Data Exchange (ETDEWEB)

    Deviers, Alexandra [Département de Radiothérapie, Institut Claudius Regaud, Toulouse (France); UMR (Unité Mixte de Recherche) 825, Institut National de la Santé et de la Recherche Médicale, Toulouse (France); INP (Institut National Polytechnique), ENVT (Ecole Nationale Vétérinaire de Toulouse), Unité d' Anatomie-Imagerie-Embryologie, Université de Toulouse, Toulouse (France); Ken, Soléakhéna [Département de Radiothérapie, Institut Claudius Regaud, Toulouse (France); UMR (Unité Mixte de Recherche) 825, Institut National de la Santé et de la Recherche Médicale, Toulouse (France); Filleron, Thomas [Bureau des Etudes Cliniques, Institut Claudius Regaud, Toulouse (France); Rowland, Benjamin; Laruelo, Andrea [Département de Radiothérapie, Institut Claudius Regaud, Toulouse (France); Catalaa, Isabelle; Lubrano, Vincent [UMR (Unité Mixte de Recherche) 825, Institut National de la Santé et de la Recherche Médicale, Toulouse (France); Hôpital de Rangueil, CHU (Centre Hospitalier Universitaire) de Toulouse, Toulouse (France); Celsis, Pierre [UMR (Unité Mixte de Recherche) 825, Institut National de la Santé et de la Recherche Médicale, Toulouse (France); and others

    2014-10-01

    Purpose: Because lactate accumulation is considered a surrogate for hypoxia and tumor radiation resistance, we studied the spatial distribution of the lactate-to-N-acetyl-aspartate ratio (LNR) before radiation therapy (RT) with 3D proton magnetic resonance spectroscopic imaging (3D-{sup 1}H-MRSI) and assessed its impact on local tumor control in glioblastoma (GBM). Methods and Materials: Fourteen patients with newly diagnosed GBM included in a phase 2 chemoradiation therapy trial constituted our database. Magnetic resonance imaging (MRI) and MRSI data before RT were evaluated and correlated to MRI data at relapse. The optimal threshold for tumor-associated LNR was determined with receiver-operating-characteristic (ROC) curve analysis of the pre-RT LNR values and MRI characteristics of the tumor. This threshold was used to segment pre-RT normalized LNR maps. Two spatial analyses were performed: (1) a pre-RT volumetric comparison of abnormal LNR areas with regions of MRI-defined lesions and a choline (Cho)-to- N-acetyl-aspartate (NAA) ratio ≥2 (CNR2); and (2) a voxel-by-voxel spatial analysis of 4,186,185 voxels with the intention of evaluating whether pre-RT abnormal LNR areas were predictive of the site of local recurrence. Results: A LNR of ≥0.4 (LNR-0.4) discriminated between tumor-associated and normal LNR values with 88.8% sensitivity and 97.6% specificity. LNR-0.4 voxels were spatially different from those of MRI-defined lesions, representing 44% of contrast enhancement, 64% of central necrosis, and 26% of fluid-attenuated inversion recovery (FLAIR) abnormality volumes before RT. They extended beyond the overlap with CNR2 for most patients (median: 20 cm{sup 3}; range: 6-49 cm{sup 3}). LNR-0.4 voxels were significantly predictive of local recurrence, regarded as contrast enhancement at relapse: 71% of voxels with a LNR-0.4 before RT were contrast enhanced at relapse versus 10% of voxels with a normal LNR (P<.01). Conclusions: Pre-RT LNR-0.4 in GBM

  5. Regulation of Signal Transduction by Glutathione Transferases

    Directory of Open Access Journals (Sweden)

    Julie Pajaud

    2012-01-01

    Full Text Available Glutathione transferases (GST are essentially known as enzymes that catalyse the conjugation of glutathione to various electrophilic compounds such as chemical carcinogens, environmental pollutants, and antitumor agents. However, this protein family is also involved in the metabolism of endogenous compounds which play critical roles in the regulation of signaling pathways. For example, the lipid peroxidation product 4-hydroxynonenal (4-HNE and the prostaglandin 15-deoxy-,14-prostaglandin J2 (15d-PGJ2 are metabolized by GSTs and these compounds are known to influence the activity of transcription factors and protein kinases involved in stress response, proliferation, differentiation, or apoptosis. Furthermore, several studies have demonstrated that GSTs are able to interact with different protein partners such as mitogen activated protein kinases (i.e., c-jun N-terminal kinase (JNK and apoptosis signal-regulating kinase 1 (ASK1 which are also involved in cell signaling. New functions of GSTs, including S-glutathionylation of proteins by GSTs and ability to be a nitric oxide (NO carrier have also been described. Taken together, these observations strongly suggest that GST might play a crucial role during normal or cancer cells proliferation or apoptosis.

  6. The Genetic Architecture of Murine Glutathione Transferases.

    Directory of Open Access Journals (Sweden)

    Lu Lu

    Full Text Available Glutathione S-transferase (GST genes play a protective role against oxidative stress and may influence disease risk and drug pharmacokinetics. In this study, massive multiscalar trait profiling across a large population of mice derived from a cross between C57BL/6J (B6 and DBA2/J (D2--the BXD family--was combined with linkage and bioinformatic analyses to characterize mechanisms controlling GST expression and to identify downstream consequences of this variation. Similar to humans, mice show a wide range in expression of GST family members. Variation in the expression of Gsta4, Gstt2, Gstz1, Gsto1, and Mgst3 is modulated by local expression QTLs (eQTLs in several tissues. Higher expression of Gsto1 in brain and liver of BXD strains is strongly associated (P < 0.01 with inheritance of the B6 parental allele whereas higher expression of Gsta4 and Mgst3 in brain and liver, and Gstt2 and Gstz1 in brain is strongly associated with inheritance of the D2 parental allele. Allele-specific assays confirmed that expression of Gsto1, Gsta4, and Mgst3 are modulated by sequence variants within or near each gene locus. We exploited this endogenous variation to identify coexpression networks and downstream targets in mouse and human. Through a combined systems genetics approach, we provide new insight into the biological role of naturally occurring variants in GST genes.

  7. Regulation of signal transduction by glutathione transferases.

    Science.gov (United States)

    Pajaud, Julie; Kumar, Sandeep; Rauch, Claudine; Morel, Fabrice; Aninat, Caroline

    2012-01-01

    Glutathione transferases (GST) are essentially known as enzymes that catalyse the conjugation of glutathione to various electrophilic compounds such as chemical carcinogens, environmental pollutants, and antitumor agents. However, this protein family is also involved in the metabolism of endogenous compounds which play critical roles in the regulation of signaling pathways. For example, the lipid peroxidation product 4-hydroxynonenal (4-HNE) and the prostaglandin 15-deoxy-Δ12,14-prostaglandin J(2) (15d-PGJ(2)) are metabolized by GSTs and these compounds are known to influence the activity of transcription factors and protein kinases involved in stress response, proliferation, differentiation, or apoptosis. Furthermore, several studies have demonstrated that GSTs are able to interact with different protein partners such as mitogen activated protein kinases (i.e., c-jun N-terminal kinase (JNK) and apoptosis signal-regulating kinase 1 (ASK1)) which are also involved in cell signaling. New functions of GSTs, including S-glutathionylation of proteins by GSTs and ability to be a nitric oxide (NO) carrier have also been described. Taken together, these observations strongly suggest that GST might play a crucial role during normal or cancer cells proliferation or apoptosis.

  8. The Genetic Architecture of Murine Glutathione Transferases.

    Science.gov (United States)

    Lu, Lu; Pandey, Ashutosh K; Houseal, M Trevor; Mulligan, Megan K

    2016-01-01

    Glutathione S-transferase (GST) genes play a protective role against oxidative stress and may influence disease risk and drug pharmacokinetics. In this study, massive multiscalar trait profiling across a large population of mice derived from a cross between C57BL/6J (B6) and DBA2/J (D2)--the BXD family--was combined with linkage and bioinformatic analyses to characterize mechanisms controlling GST expression and to identify downstream consequences of this variation. Similar to humans, mice show a wide range in expression of GST family members. Variation in the expression of Gsta4, Gstt2, Gstz1, Gsto1, and Mgst3 is modulated by local expression QTLs (eQTLs) in several tissues. Higher expression of Gsto1 in brain and liver of BXD strains is strongly associated (P < 0.01) with inheritance of the B6 parental allele whereas higher expression of Gsta4 and Mgst3 in brain and liver, and Gstt2 and Gstz1 in brain is strongly associated with inheritance of the D2 parental allele. Allele-specific assays confirmed that expression of Gsto1, Gsta4, and Mgst3 are modulated by sequence variants within or near each gene locus. We exploited this endogenous variation to identify coexpression networks and downstream targets in mouse and human. Through a combined systems genetics approach, we provide new insight into the biological role of naturally occurring variants in GST genes.

  9. Interactions of glutathione transferases with 4-hydroxynonenal.

    Science.gov (United States)

    Balogh, Larissa M; Atkins, William M

    2011-05-01

    Electrophilic products of lipid peroxidation are important contributors to the progression of several pathological states. The prototypical α,β-unsaturated aldehyde, 4-hydroxynonenal (HNE), triggers cellular events associated with oxidative stress, which can be curtailed by the glutathione-dependent elimination of HNE. The glutathione transferases (GSTs) are a major determinate of the intracellular concentration of HNE and can influence susceptibility to toxic effects, particularly when HNE and GST levels are altered in disease states. In this article, we provide a brief summary of the cellular effects of HNE, followed by a review of its GST-catalyzed detoxification, with an emphasis on the structural attributes that play an important role in the interactions with alpha-class GSTs. Some of the key determining characteristics that impart high alkenal activity reside in the unique C-terminal interactions of the GSTA4-4 enzyme. Studies encompassing both kinetic and structural analyses of related isoforms will be highlighted, with additional attention to stereochemical aspects that demonstrate the capacity of GSTA4-4 to detoxify both enantiomers of the biologically relevant racemic mixture while generating a select set of diastereomeric products with subsequent implications. A summary of the literature that examines the interplay between GSTs and HNE in model systems relevant to oxidative stress will also be discussed to demonstrate the magnitude of importance of GSTs in the overall detoxification scheme.

  10. Sustainable Consumption

    DEFF Research Database (Denmark)

    Røpke, Inge

    2015-01-01

    The intention of this chapter is to explore the role of consumption and consumers in relation to sustainability transition processes and wider systemic transformations. In contrast to the individualistic focus in much research on sustainable consumption, the embeddedness of consumption activities...... in wider social, economic and technological frameworks is emphasised. In particular, the chapter is inspired by practice theory and transition theory. First, various trends in consumption are outlined to highlight some of the challenges for sustainability transitions. Then, it is discussed how consumption...... patterns are shaped over time and what should be considered in sustainability strategies. While discussions on consumption often take their point of departure in the perspective of the individual and then zoom to the wider context, the present approach is the opposite. The outline starts with the basic...

  11. Glutathione transferase mimics : Micellar catalysis of an enzymic reaction

    NARCIS (Netherlands)

    Lindkvist, Björn; Weinander, Rolf; Engman, Lars; Koetse, Marc; Engberts, Jan B.F.N.; Morgenstern, Ralf

    1997-01-01

    Substances that mimic the enzyme action of glutathione transferases (which serve in detoxification) are described. These micellar catalysts enhance the reaction rate between thiols and activated halogenated nitroarenes as well as alpha,beta-unsaturated carbonyls. The nucleophilic aromatic substituti

  12. Differences in quantification of DNA double-strand breaks assessed by 53BP1/γH2AX focus formation assays and the comet assay in mammalian cells treated with irradiation and N-acetyl-L-cysteine.

    Science.gov (United States)

    Kurashige, Tomomi; Shimamura, Mika; Nagayama, Yuji

    2016-06-01

    The biological effect of ionizing radiation (IR) on genomic DNA is thought to be either direct or indirect; the latter is mediated by IR induction of free radicals and reactive oxygen species (ROS). This study was designed to evaluate the effect of N-acetyl-L-cysteine (NAC), a well-known ROS-scavenging antioxidant, on IR induction of genotoxicity, cytotoxicity and ROS production in mammalian cells, and aimed to clarify the conflicting data in previous publications. Although we clearly demonstrate the beneficial effect of NAC on IR-induced genotoxicity and cytotoxicity (determined using the micronucleus assay and cell viability/clonogenic assays), the data on NAC's effect on DNA double-strand break (DSB) formation were inconsistent in different assays. Specifically, mitigation of IR-induced DSBs by NAC was readily detected by the neutral comet assay, but not by the γH2AX or 53BP1 focus assays. NAC is a glutathione precursor and exerts its effect after conversion to glutathione, and presumably it has its own biological activity. Assuming that the focus assay reflects the biological responses to DSBs (detection and repair), while the comet assay reflects the physical status of genomic DNA, our results indicate that the comet assay could readily detect the antioxidant effect of NAC on DSB formation. However, NAC's biological effect might affect the detection of DSB repair by the focus assays. Our data illustrate that multiple parameters should be carefully used to analyze DNA damage when studying potential candidates for radioprotective compounds.

  13. N-acetyl cysteine protects human oral keratinocytes from Bis-GMA-induced apoptosis and cell cycle arrest by inhibiting reactive oxygen species-mediated mitochondrial dysfunction and the PI3K/Akt pathway.

    Science.gov (United States)

    Zhu, Yu; Gu, Ying-xin; Mo, Jia-ji; Shi, Jun-yu; Qiao, Shi-chong; Lai, Hong-chang

    2015-12-01

    Bisphenol-A-glycidyl methacrylate (Bis-GMA) released from dental resin materials causes various toxic effects on gingival epithelium. Thus the underlying mechanisms of its cytotoxicity should be elucidated for safety use. One potential cause of cell damage is the generation of reactive oxygen species (ROS) beyond the capacity of a balanced redox regulation. In this study, we found that exposure of human oral keratinocytes (HOKs) to Bis-GMA caused apoptosis and G1/S cell cycle arrest in parallel with an increased ROS level. Moreover, Bis-GMA induced a depletion of mitochondrial membrane potential, an increase in the Bax/Bcl-2 ratio, an activation of caspase-3 and altered expressions of cell cycle-related proteins (p21, PCNA, cyclinD1). Furthermore, the co-treatment of the ROS scavenger N-acetyl cysteine (NAC) obviously attenuated Bis-GMA-induced toxicity. Here we also evaluated the effects of Bis-GMA on the ROS-related PI3k/Akt pathway. We found that Bis-GMA inhibited the phosphorylation of Akt, whereas the amount of phosphorylated Akt was reverted to the control level in the presence of NAC. Our findings suggested that the toxic effects of Bis-GMA were related to ROS production and the antioxidant NAC effectively reduced Bis-GMA-mediated cytotoxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Molecular Signatures in the Prevention of Radiation Damage by the Synergistic Effect of N-Acetyl Cysteine and Qingre Liyan Decoction, a Traditional Chinese Medicine, Using a 3-Dimensional Cell Culture Model of Oral Mucositis

    Directory of Open Access Journals (Sweden)

    Maria P. Lambros

    2015-01-01

    Full Text Available Qingre Liyan decoction (QYD, a Traditional Chinese medicine, and N-acetyl cysteine (NAC have been used to prevent radiation induced mucositis. This work evaluates the protective mechanisms of QYD, NAC, and their combination (NAC-QYD at the cellular and transcriptional level. A validated organotypic model of oral mucosal consisting of a three-dimensional (3D cell tissue-culture of primary human keratinocytes exposed to X-ray irradiation was used. Six hours after the irradiation, the tissues were evaluated by hematoxylin and eosin (H and E and a TUNEL assay to assess histopathology and apoptosis, respectively. Total RNA was extracted and used for microarray gene expression profiling. The tissue-cultures treated with NAC-QYD preserved their integrity and showed no apoptosis. Microarray results revealed that the NAC-QYD caused the upregulation of genes encoding metallothioneins, HMOX1, and other components of the Nrf2 pathway, which protects against oxidative stress. DNA repair genes (XCP, GADD45G, RAD9, and XRCC1, protective genes (EGFR and PPARD, and genes of the NFκB pathway were upregulated. Finally, tissue-cultures treated prophylactically with NAC-QYD showed significant downregulation of apoptosis, cytokines and chemokines genes, and constrained damage-associated molecular patterns (DAMPs. NAC-QYD treatment involves the protective effect of Nrf2, NFκB, and DNA repair factors.

  15. The combination of N-acetyl cysteine, alpha-lipoic acid, and bromelain shows high anti-inflammatory properties in novel in vivo and in vitro models of endometriosis.

    Science.gov (United States)

    Agostinis, C; Zorzet, S; De Leo, R; Zauli, G; De Seta, F; Bulla, R

    2015-01-01

    To evaluate the efficacy of an association of N-acetyl cystein, alpha-lipoic acid, and bromelain (NAC/LA/Br) in the treatment of endometriosis we set up a new in vivo murine model. We explored the anti-inflammatory and proapoptotic effect of this combination on human endometriotic endothelial cells (EECs) and on endothelial cells isolated from normal uterus (UtMECs). We implanted fragments of human endometriotic cysts intraperitoneally into SCID mice to evaluate the efficacy of NAC/LA/Br treatment. UtMECs and EECs, untreated or treated with NAC/LA/Br, were activated with the proinflammatory stimulus TNF-α and their response in terms of VCAM1 expression was evaluated. The proapoptotic effect of higher doses of NAC/LA/Br on UtMECs and EECs was measured with a fluorogenic substrate for activated caspases 3 and 7. The preincubation of EECs with NAC/LA/Br prior to cell stimulation with TNF-α prevents the upregulation of the expression of the inflammatory "marker" VCAM1. Furthermore NAC/LA/Br were able to induce EEC, but not UtMEC, apoptosis. Finally, the novel mouse model allowed us to demonstrate that mice treated with NAC/LA/Br presented a lower number of cysts, smaller in size, compared to untreated mice. Our findings suggest that these dietary supplements may have potential therapeutic uses in the treatment of chronic inflammatory diseases like endometriosis.

  16. The Combination of N-Acetyl Cysteine, Alpha-Lipoic Acid, and Bromelain Shows High Anti-Inflammatory Properties in Novel In Vivo and In Vitro Models of Endometriosis

    Directory of Open Access Journals (Sweden)

    C. Agostinis

    2015-01-01

    Full Text Available To evaluate the efficacy of an association of N-acetyl cystein, alpha-lipoic acid, and bromelain (NAC/LA/Br in the treatment of endometriosis we set up a new in vivo murine model. We explored the anti-inflammatory and proapoptotic effect of this combination on human endometriotic endothelial cells (EECs and on endothelial cells isolated from normal uterus (UtMECs. We implanted fragments of human endometriotic cysts intraperitoneally into SCID mice to evaluate the efficacy of NAC/LA/Br treatment. UtMECs and EECs, untreated or treated with NAC/LA/Br, were activated with the proinflammatory stimulus TNF-α and their response in terms of VCAM1 expression was evaluated. The proapoptotic effect of higher doses of NAC/LA/Br on UtMECs and EECs was measured with a fluorogenic substrate for activated caspases 3 and 7. The preincubation of EECs with NAC/LA/Br prior to cell stimulation with TNF-α prevents the upregulation of the expression of the inflammatory “marker” VCAM1. Furthermore NAC/LA/Br were able to induce EEC, but not UtMEC, apoptosis. Finally, the novel mouse model allowed us to demonstrate that mice treated with NAC/LA/Br presented a lower number of cysts, smaller in size, compared to untreated mice. Our findings suggest that these dietary supplements may have potential therapeutic uses in the treatment of chronic inflammatory diseases like endometriosis.

  17. Potentiation of LPS-Induced Apoptotic Cell Death in Human Hepatoma HepG2 Cells by Aspirin via ROS and Mitochondrial Dysfunction: Protection by N-Acetyl Cysteine.

    Directory of Open Access Journals (Sweden)

    Haider Raza

    Full Text Available Cytotoxicity and inflammation-associated toxic responses have been observed to be induced by bacterial lipopolysaccharides (LPS in vitro and in vivo respectively. Use of nonsteroidal anti-inflammatory drugs (NSAIDs, such as aspirin, has been reported to be beneficial in inflammation-associated diseases like cancer, diabetes and cardiovascular disorders. Their precise molecular mechanisms, however, are not clearly understood. Our previous studies on aspirin treated HepG2 cells strongly suggest cell cycle arrest and induction of apoptosis associated with mitochondrial dysfunction. In the present study, we have further demonstrated that HepG2 cells treated with LPS alone or in combination with aspirin induces subcellular toxic responses which are accompanied by increase in reactive oxygen species (ROS production, oxidative stress, mitochondrial respiratory dysfunction and apoptosis. The LPS/Aspirin induced toxicity was attenuated by pre-treatment of cells with N-acetyl cysteine (NAC. Alterations in oxidative stress and glutathione-dependent redox-homeostasis were more pronounced in mitochondria compared to extra- mitochondrial cellular compartments. Pre-treatment of HepG2 cells with NAC exhibited a selective protection in redox homeostasis and mitochondrial dysfunction. Our results suggest that the altered redox metabolism, oxidative stress and mitochondrial function in HepG2 cells play a critical role in LPS/aspirin-induced cytotoxicity. These results may help in better understanding the pharmacological, toxicological and therapeutic properties of NSAIDs in cancer cells exposed to bacterial endotoxins.

  18. Anti-malarial effect of 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one and green tea extract on erythrocyte-stage Plasmodium berghei in mice

    Institute of Scientific and Technical Information of China (English)

    Phitsinee; Thipubon; Wachiraporn; Tipsuwan; Chairat; Uthaipibull; Sineenart; Santitherakul; Somdet; Srichiratanakool

    2015-01-01

    Objective: To examine the efficacy of 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one(CM1) iron chelator and green tea extract(GTE) as anti-malarial activity in Plasmodium berghei(P. berghei) infected mice.Methods: The CM1(0–100 mg/kg/day) and GTE(0–100 mg(-)-epigallocatechin 3-gallate equivalent/kg/day) were orally administered to P. berghei infected mice for consecutive 4 days. Parasitized red blood cells(PRBC) were enumerated by using Giemsa staining microscopic method.Results: CM1 lowered percentage of PRBC in dose-dependent manner with an ED50 value of 56.91 mg/kg, when compared with pyrimethamine(PYR)(ED50= 0.76 mg/kg).GTE treatment did not show any inhibition of the malaria parasite growth. In combined treatment, CM1 along with 0.6 mg/kg PYR significantly inhibited the growth of P. berghei in mice while GTE did not enhance the PYR anti-malarial activity.Conclusions: CM1 would be effective per se and synergize with PYR in inhibiting growth of murine malaria parasites, possibly by limiting iron supply from plasma transferrin and host PRBC cytoplasm, and chelating catalytic iron cstitutive in parasites’ mitochondrial cytochromes and cytoplasmic ribonucleotide reductase. CM1 would be a promising adjuvant to enhance PYR anti-malarial activity and minimize the drug resistance.

  19. Anti-malarial effect of 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one and green tea extract on erythrocyte-stage Plasmodium berghei in mice

    Institute of Scientific and Technical Information of China (English)

    Phitsinee Thipubon; Wachiraporn Tipsuwan; Chairat Uthaipibull; Sineenart Santitherakul; Somdet Srichiratanakool

    2015-01-01

    Objective:To examine the efficacy of 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one (CM1) iron chelator and green tea extract (GTE) as anti-malarial activity in Plasmodium berghei (P. berghei ) infected mice. Methods:The CM1 (0–100 mg/kg/day) and GTE (0–100 mg (-)-epigallocatechin 3-gallate equivalent/kg/day) were orally administered to P. berghei infected mice for consecutive 4 days. Parasitized red blood cells (PRBC) were enumerated by using Giemsa staining microscopic method. Results: CM1 lowered percentage of PRBC in dose-dependent manner with an ED50 value of 56.91 mg/kg, when compared with pyrimethamine (PYR) (ED50=0.76 mg/kg). GTE treatment did not show any inhibition of the malaria parasite growth. In combined treatment, CM1 along with 0.6 mg/kg PYR significantly inhibited the growth of P. berghei in mice while GTE did not enhance the PYR anti-malarial activity. Conclusions: CM1 would be effective per se and synergize with PYR in inhibiting growth of murine malaria parasites, possibly by limiting iron supply from plasma transferrin and host PRBC cytoplasm, and chelating catalytic iron constitutive in parasites’ mitochondrial cytochromes and cytoplasmic ribonucleotide reductase. CM1 would be a promising adjuvant to enhance PYR anti-malarial activity and minimize the drug resistance.

  20. Reduction in the appearance of facial hyperpigmentation after use of moisturizers with a combination of topical niacinamide and N-acetyl glucosamine: results of a randomized, double-blind, vehicle-controlled trial.

    Science.gov (United States)

    Kimball, A B; Kaczvinsky, J R; Li, J; Robinson, L R; Matts, P J; Berge, C A; Miyamoto, K; Bissett, D L

    2010-02-01

    Topical niacinamide and N-acetyl glucosamine (NAG) each individually inhibit epidermal pigmentation in cell culture. In small clinical studies, niacinamide-containing and NAG-containing formulations reduced the appearance of hyperpigmentation. To assess the effect of a combination of niacinamide and NAG in a topical moisturizing formulation on irregular facial pigmentation, including specific detection of changes in colour features associated with melanin. This was a 10-week, double-blind, vehicle-controlled, full-face, parallel-group clinical study conducted in women aged 40-60 years. After a 2-week washout period, subjects used a daily regimen of either a morning sun protection factor (SPF) 15 sunscreen moisturizing lotion and evening moisturizing cream each containing 4% niacinamide + 2% NAG (test formulation; n = 101) or the SPF 15 lotion and cream vehicles (vehicle control; n = 101). Product-induced changes in apparent pigmentation were assessed by capturing digital photographic images of the women after 0, 4, 6 and 8 weeks of product use and evaluating the images by algorithm-based computer image analysis for coloured spot area fraction, by expert visual grading, and by chromophore-specific image analysis based on noncontact SIAscopy for melanin spot area fraction and melanin chromophore evenness. By all four measures, the niacinamide + NAG formulation regimen was significantly (P niacinamide + NAG reduced the appearance of irregular pigmentation including hypermelaninization, providing an effect beyond that achieved with SPF 15 sunscreen.

  1. Iron-chelating and anti-lipid peroxidation properties of 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one(CM1)in longterm iron loading β-thalassemic mice

    Institute of Scientific and Technical Information of China (English)

    Kanokwan; Kulprachakarn; Nittaya; Chansiw; Kanjana; Pangjit; Chada; Phisalaphong; Suthat; Fucharoen; Robert; C.Hider; Sineenart; Santitherakul; Somdet; Srichairatanakool

    2014-01-01

    Objective:To evaluate the iron—chelating properties and free—radical scavenging activities of1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methyIpyridin—4-one(CM1) treatment in chronic iron-loaded β-thalassemic(BKO) mice.Methods:The BKO mice were fed with a ferrocene-rich diet and were orally administered with CM1|50 mg/(kg·day)| for 6 months.Blood levels of non-transferrin hound iron,labile plasma iron.ferritin(Ft) and malondialdehyde were determined.Results:The BKO mice were fed with an iron diet for 8 months which resulted in iron overload.Interestingly,the mice showed a decrease in the non—transferrin bound iron,labile plasma iron and malondialdehyde levels,but not the Ft levels after continuous CM1 treatment.Conclusions:CM1 could be an effective oral iron chelator that can reduce iron overload and lipid peroxidation in chronic iron overload β—thalassemic mice.

  2. Role of N-acetyl-chito-oligosaccharides in Plant Diseases Biological Control of Trichoderma spp.%几丁寡糖在木霉菌生物防治中的作用

    Institute of Scientific and Technical Information of China (English)

    姚艳平; 王建明; 张作刚; 李友莲

    2013-01-01

    木霉菌是重要的植物病害生防菌,在与植物病原真菌的拮抗过程中可产生一种特殊的化合物——几丁寡糖,几丁寡糖在木霉菌生防中具有多种生物功能.从真菌细胞壁和节肢动物外骨胳中分离的几丁寡糖,可充当化学激发子、诱导植物产生抗性、激发植物的防御系统、提高植物的抗病性.%The fungous Trichoderma is an important microorganism in the biological control of plant diseases. A special compound, N—acetyl—chito—oligosaccharides, could be produced by Trichoderma spp. In antagonism process with plant fungous pathogens. N-acetyl-chito-oligosaccharides are involved in a variety of biological events of Trichoderma. As part of the exoskele-ton of different insects and fungi, they could act as chemical signals to induce resistance, inspire defense system, and to improve resistant ability against plant diseases.

  3. Cyclic 3′,5′-Adenosine Monophosphate and N-Acetyl-glucosamine-6-Phosphate as Regulatory Signals in Catabolite Repression of the lac Operon in Escherichia coli1

    Science.gov (United States)

    Goldenbaum, Paul E.; Broman, Rodney L.; Dobrogosz, Walter J.

    1970-01-01

    When an Escherichia coli mutant lacking the enzyme N-acetyl-glucosamine-6-phosphate (AcGN6P) deacetylase is grown in a succinate-mineral salts medium and exposed to an exogenous source of N-acetylglucosamine, approximately 20 to 30 pmoles of AcGN6P per μg of cell dry weight will accumulate in these cells. This accumulation occurs within 2 to 4 min after the addition of N-acetylglucosamine and is coincident with the production of a severe permanent catabolite repression of β-galactosidase synthesis. This repression does not occur if adenosine 3′,5′-cyclic phosphate (cyclic AMP) is added to the cells before AcGN6P accumulates. An immediate derepression occurs when cyclic AMP is added to cells that have already accumulated a large AcGN6P pool. These findings are consistent with the view that low-molecular-weight carbohydrate metabolites and cyclic AMP play key roles in the catabolite repression phenomenon, and that metabolites such as AcGN6P may participate in the represion mechanism by influencing either the formation or degradation of cyclic AMP in E. coli. PMID:4319836

  4. Cu²⁺ functionalized N-acetyl-L-cysteine capped CdTe quantum dots as a novel resonance Rayleigh scattering probe for the recognition of phenylalanine enantiomers.

    Science.gov (United States)

    Yang, Jidong; Tan, Xuanping; Zhang, Xiaoning; Yang, Qiong; Shen, Yizhong

    2015-01-01

    A simple protocol that can be used to simultaneously determinate enantiomers is extremely intriguing and useful. In this study, we proposed a low-cost, facile, sensitive method for simultaneous determination. The molecular recognition of Cu(2+) functionalized N-acetyl-l-cysteine capped CdTe quantum dots (Cu(2+)-NALC/CdTe QDs) with phenylalanine (PA) enantiomers was investigated based on the resonance Rayleigh scattering (RRS) spectral technique. The RRS intensity of NALC/CdTe QDs is very weak, but Cu(2+) functionalized NALC/CdTe QDs have extremely high RRS intensity, the most important observations are that PA could quench the RRS intensity of Cu(2+)-NALC/CdTe QDs, and that l-PA and d-PA have different degree of influence. In addition, those experimental factors such as acidity, concentration of Cu(2+) and reaction time were investigated in regards to their effects on enantioselective interaction. Finally, the applicability of the chiral recognized sensor for the analysis of chiral mixtures on enantiomers has been demonstrated, and the results that were obtained high precision (<4.63%) and low error (<3.06%).

  5. Glutathione transferases in the bioactivation of azathioprine.

    Science.gov (United States)

    Modén, Olof; Mannervik, Bengt

    2014-01-01

    The prodrug azathioprine is primarily used for maintaining remission in inflammatory bowel disease, but approximately 30% of the patients suffer adverse side effects. The prodrug is activated by glutathione conjugation and release of 6-mercaptopurine, a reaction most efficiently catalyzed by glutathione transferase (GST) A2-2. Among five genotypes of GST A2-2, the variant A2*E has threefold-fourfold higher catalytic efficiency with azathioprine, suggesting that the expression of A2*E could boost 6-mercaptopurine release and adverse side effects in treated patients. Structure-activity studies of the GST A2-2 variants and homologous alpha class GSTs were made to delineate the determinants of high catalytic efficiency compared to other alpha class GSTs. Engineered chimeras identified GST peptide segments of importance, and replacing the corresponding regions in low-activity GSTs by these short segments produced chimeras with higher azathioprine activity. By contrast, H-site mutagenesis led to decreased azathioprine activity when active-site positions 208 and 213 in these favored segments were mutagenized. Alternative substitutions indicated that hydrophobic residues were favored. A pertinent question is whether variant A2*E represents the highest azathioprine activity achievable within the GST structural framework. This issue was addressed by mutagenesis of H-site residues assumed to interact with the substrate based on molecular modeling. The mutants with notably enhanced activities had small or polar residues in the mutated positions. The most active mutant L107G/L108D/F222H displayed a 70-fold enhanced catalytic efficiency with azathioprine. The determination of its structure by X-ray crystallography showed an expanded H-site, suggesting improved accommodation of the transition state for catalysis.

  6. EVALUATION OF SERUM CHOLESTEROL, AMINO TRANSFERASES

    Directory of Open Access Journals (Sweden)

    Anantha Babu

    2016-01-01

    Full Text Available BACKGROUND AND AIMS The purpose of this study was to determine the efficacy of red yeast rice (Monascus purpureus-fermented rice in lowering cholesterol in the blood. At the same time, alanine aminotranferase (ALT, aspartate aminotransferase (AST and gamma-glutamyl transferase (γ-GT were measured for notable side effects in the liver. Possible muscle damage was determined by measuring creatine kinase (CK. METHODS The cholesterol lowering effect in serum of red yeast rice-fed rats were studied over a 42-day feeding period. A total of 16 male Sprague-Dawley rats were randomised into 8 per group: control and treated. Treated rats were administered 1.35g/kg/day. Control rats were maintained on ordinary rat chow. RESULTS Serum cholesterol levels were significantly decreased by 19.13% in treated group compared to controls. This treatment also showed increase in serum ALT and AST activities by 41.90% and 21.53%, respectively. Mean CK activity in treated rats showed an increase by 32.32% when compared with control rats. γ-GT is the only enzyme that showed a decrease of 15.16% in sera of treated rats. Body weights of control and treated rats increased significantly by 10% end of feeding period but were not due to treatment. CONCLUSION Red yeast rice significantly decreased serum cholesterol level at a dosage of 1.35g/kg/day. However, the differences in serum enzyme activities between control and treated rats were not significant.

  7. Glutathione transferase from Trichoderma virens enhances cadmium tolerance without enhancing its accumulation in transgenic Nicotiana tabacum.

    Directory of Open Access Journals (Sweden)

    Prachy Dixit

    Full Text Available 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

  8. Sustainable consumption

    DEFF Research Database (Denmark)

    Prothero, Andrea; Dobscha, Susan; Freund, Jim

    2011-01-01

    This essay explores sustainable consumption and considers possible roles for marketing and consumer researchers and public policy makers in addressing the many sustainability challenges that pervade our planet. Future research approaches to this interdisciplinary topic need to be comprehensive...

  9. Conspicuous Consumption

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    China validated a new consumption tax policy on April 1 that levies higher taxes on luxury goods such as yachts and limousines, as well as wooden disposable chopsticks and wooden flooring. This marked the most profound change in the consumption tax since 1994 and is thought to be the first step in an overall tax reform in the country. Consumer tariffs, which are handed over to state coffers, consist of excise taxes and the taxes on imported goods collected by customs agencies.

  10. Development of an HPLC-MS procedure for the quantification of N-acetyl-S-(n-propyl)-l-cysteine, the major urinary metabolite of 1-bromopropane in human urine.

    Science.gov (United States)

    Cheever, K L; Marlow, K L; B'hymer, C; Hanley, K W; Lynch, D W

    2009-03-15

    An analytical procedure was developed for the detection and quantification of N-acetyl-S-(n-propyl)-l-cysteine (n-propylmercapturic acid, AcPrCys), a metabolite and biomarker for exposure to 1-bromopropane (1-BP). 1-BP is used as an industrial solvent and exposure is a health concern for industrial workers due to its toxicity. It has been associated with neurological disorders in both animals and humans. Urine sample preparation for the determination of AcPrCys consisted of solid phase extraction (SPE). Urine samples on preconditioned SPE (C18) columns were washed with 40% methanol/60% water solution prior to elution with acetone. Quantification was by means of a liquid chromatograph (LC) equipped with a mass spectrometer (MS) using an Aqua 3 microm C18 300A column and [d(7)]-AcPrCys was used as internal standard. Electrospray ionization (ESI) was used with the MS operated in the negative ion mode and selected ion monitoring (SIM) at m/z 204 for AcPrCys and m/z 211 for [d(7)]-AcPrCys. Demonstrated recovery of urine samples fortified at multiple levels (0.625-10 microg/ml) varied between 96 and 103% of theory with relative standard deviations (RSD) of 6.4% or less. The limit of detection (LOD) for the procedure was approximately 0.01 microg/ml AcPrCys in urine. These data will be discussed as well as other factors of the development of this test procedure.

  11. The matrikine N-acetylated proline-glycine-proline induces premature senescence of nucleus pulposus cells via CXCR1-dependent ROS accumulation and DNA damage and reinforces the destructive effect of these cells on homeostasis of intervertebral discs.

    Science.gov (United States)

    Feng, Chencheng; Zhang, Yang; Yang, Minghui; Lan, Minghong; Liu, Huan; Wang, Jian; Zhou, Yue; Huang, Bo

    2017-01-01

    Intervertebral disc (IVD) cell senescence is a recognized mechanism of intervertebral disc degeneration (IDD). Elucidating the molecular mechanisms underlying disc cell senescence will contribute to understanding the pathogenesis of IDD. We previously reported that N-acetylated proline-glycine-proline (N-Ac-PGP), a matrikine, is involved in the process of IDD. However, its roles in IDD are not well understood. Here, using rat nucleus pulposus (NP) cells, we found that N-Ac-PGP induced premature senescence of NP cells by binding to CXCR1. N-Ac-PGP induced DNA damage and reactive oxygen species accumulation in NP cells, which resulted in activation of the p53-p21-Rb and p16-Rb pathways. Moreover, the RT(2) profiler PCR array showed that N-Ac-PGP down-regulates the expression of antioxidant genes in NP cells, suggesting a decline in the antioxidants of NP cells. On the other hand, N-Ac-PGP up-regulated the expression of matrix catabolic genes and inflammatory genes in NP cells. Concomitantly, N-Ac-PGP reinforced the destructive effects of senescent NP cells on the homeostasis of the IVDs in vivo. Our study suggests that N-Ac-PGP plays critical roles in the pathogenesis of IDD through the induction of premature senescence of disc cells and via the activation of catabolic and inflammatory cascades in disc cells. N-Ac-PGP also deteriorates the redox environment of disc cells. Hence, N-Ac-PGP is a new potential therapeutic target for IDD.

  12. Simultaneous determination of N-hydroxymethyl-N-methylformamide, N-methylformamide and N-acetyl-S-(N-methylcarbamoyl)cystein in urine samples from workers exposed to N,N-dimethylformamide by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Sohn, Jae Ho; Han, Min Jeong; Lee, Mi Young; Kang, Seong-Kyu; Yang, Jeong Sun

    2005-02-07

    N-Hydroxymethyl-N-methylformamide (HMMF) and N-methylformamide (NMF) in urine samples from workers exposed to N,N-dimethylformamide (DMF) cannot be distinguished by a gas chromatographic method because HMMF is converted to NMF at the injection port of gas chromatography (GC). Total NMF (HMMF+NMF) has been measured instead. Also, the determination of N-acetyl-S-(N-methylcarbamoyl)cystein (AMCC), which is supposed to be related to the toxicity of DMF, needs multiple treatments to convert to a volatile compound before GC analysis. There is no previous report of a simultaneous determination of three major metabolites of DMF in urine. The aim of this study is to develop a simple and selective method for the determination of DMF metabolite in urine. By using a liquid chromatography-tandem mass spectrometry, we can directly distinguish these three major metabolites of DMF in a single run. The diluted urine samples were analyzed on Capcell Pak MF SG80 column with the mobile phase of methanol in 2mM formic acid (10:90, v/v). The analytes were detected by an electrospray ionization tandem mass spectrometry in the multiple-reaction-monitoring mode. The standard curves were linear (r>0.999) over the concentration ranges of 0.004-8 microg/mL. The precision and accuracy of quality control samples for inter-batch (n=6) analyses were in the range of 1.3-9.8% and 94.7-116.8, respectively. The sum of each HMMF and NMF concentration determined by LC-MS/MS method shows high correlation (r=0.9927 with the slope of 1.0415, p<0.0001) with NMF included HMMF concentration determined by GC method for 13 urine samples taken from workers exposed to DMF. The excretion ratio of HMMF:NMF:AMCC is approximately 4:1:1 in molar concentration.

  13. Neuroprotective action of N-acetyl serotonin in oxidative stress-induced apoptosis through the activation of both TrkB/CREB/BDNF pathway and Akt/Nrf2/Antioxidant enzyme in neuronal cells.

    Science.gov (United States)

    Yoo, Jae-Myung; Lee, Bo Dam; Sok, Dai-Eun; Ma, Jin Yuel; Kim, Mee Ree

    2017-04-01

    N-acetyl serotonin (NAS) as a melatonin precursor has neuroprotective actions. Nonetheless, it is not clarified how NAS protects neuronal cells against oxidative stress. Recently, we have reported that N-palmitoyl serotonins possessed properties of antioxidants and neuroprotection. Based on those, we hypothesized that NAS, a N-acyl serotonin, may have similar actions in oxidative stress-induced neuronal cells, and examined the effects of NAS based on in vitro and in vivo tests. NAS dose-dependently inhibited oxidative stress-induced cell death in HT-22 cells. Moreover, NAS suppressed glutamate-induced apoptosis by suppressing expression of AIF, Bax, calpain, cytochrome c and cleaved caspase-3, whereas it enhanced expression of Bcl-2. Additionally, NAS improved phosphorylation of tropomyosin-related kinase receptor B (TrkB) and cAMP response element-binding protein (CREB) as well as expression of brain-derived neurotrophic factor (BDNF), whereas the inclusion of each inhibitor of JNK, p38 or Akt neutralized the neuroprotective effect of NAS, but not that of ERK. Meanwhile, NAS dose-dependently reduced the level of reactive oxygen species, and enhanced the level of glutathione in glutamate-treated HT-22 cells. Moreover, NAS significantly increased expression of heme oxygenase-1, NAD(P)H quinine oxidoreductase-1 and glutamate-cysteine ligase catalytic subunit as well as nuclear translocation of NF-E2-related factor-2. Separately, NAS at 30mg/kg suppressed scopolamine-induced memory impairment and cell death in CA1 and CA3 regions in mice. In conclusion, NAS shows actions of antioxidant and anti-apoptosis by activating TrkB/CREB/BDNF pathway and expression of antioxidant enzymes in oxidative stress-induced neurotoxicity. Therefore, such effects of NAS may provide the information for the application of NAS against neurodegenerative diseases.

  14. Over-expression of a tomato N-acetyl-L-glutamate synthase gene (SlNAGS1) in Arabidopsis thaliana results in high ornithine levels and increased tolerance in salt and drought stresses.

    Science.gov (United States)

    Kalamaki, Mary S; Alexandrou, Dimitris; Lazari, Diamanto; Merkouropoulos, Georgios; Fotopoulos, Vasileios; Pateraki, Irene; Aggelis, Alexandros; Carrillo-López, Armando; Rubio-Cabetas, Maria J; Kanellis, Angelos K

    2009-01-01

    A single copy of the N-acetyl-L-glutamate synthase gene (SlNAGS1) has been isolated from tomato. The deduced amino acid sequence consists of 604 amino acids and shows a high level of similarity to the predicted Arabidopsis NAGS1 and NAGS2 proteins. Furthermore, the N-terminus ArgB domain and the C-terminus ArgA domain found in SlNAGS1 are similar to the structural arrangements that have been reported for other predicted NAGS proteins. SlNAGS1 was expressed at high levels in all aerial organs, and at basic levels in seeds, whereas it was not detected at all in roots. SlNAGS1 transcript accumulation was noticed transiently in tomato fruit at the red-fruit stage. In addition, an increase of SlNAGS1 transcripts was detected in mature green tomato fruit within the first hour of exposure to low oxygen concentrations. Transgenic Arabidopsis plants have been generated expressing the SlNAGS1 gene under the control of the cauliflower mosaic virus (CaMV) 35S promoter. Three homozygous transgenic lines expressing the transgene (lines 1-7, 3-8, and 6-5) were evaluated further. All three transgenic lines showed a significant accumulation of ornithine in the leaves with line 3-8 exhibiting the highest concentration. The same lines demonstrated higher germination ability compared to wild-type (WT) plants when subjected to 250 mM NaCl. Similarly, mature plants of all three transgenic lines displayed a higher tolerance to salt and drought stress compared to WT plants. Under most experimental conditions, transgenic line 3-8 performed best, while the responses obtained from lines 1-7 and 6-5 depended on the applied stimulus. To our knowledge, this is the first plant NAGS gene to be isolated, characterized, and genetically modified.

  15. 尿mALB与NAG联合检测对糖尿病肾病早期的诊断意义%The significance of detecting urine microalbumin and n-acetyl-β-D-glucosaminidase in diagnosis of early diabetic nephropathy

    Institute of Scientific and Technical Information of China (English)

    肖春燕

    2012-01-01

    目的 探讨尿微量白蛋白(mALB)与N-乙酰-β-D-氨基葡萄糖苷酶(NAG)联合检测对糖尿病肾病早期的诊断意义.方法 检测58例糖尿病肾病早期患者的尿mALB和NAG酶等指标,同时随机选择48名健康体检者为对照组.结果 糖尿病肾病早期组患者的尿mALB和NAG与对照组比较均明显上升(P<0.01);血糖控制良好患者的尿mALB和NAG明显低于血糖控制欠佳组(P<0.01).结论 尿mALB与NAG联合检测对糖尿病肾病早期有重要的诊断价值.%Objective To explore the significance of detecting urine microalbumin ( mALB ) and n - acetyl - β - D - glucosaminidase ( NAG ) in diagnosis of early diabetic nephropathy. Methods The urine mALB and NAG were examined in 58 patients for early diagnosis of diabetic nephropathy, and 48 healthy persons were randomly selected as healthy controls. Results Compared with control group, urine levels of mALB and NAG in patients with early diabetic nephropathy were significantly decreased( P < 0. 01 ). Compared with poor control group, urine levels of mALB and NAG in good control group were significantly decreased ( P <0. 01 ). Conclusion The combined detection of urine mALB and NAG in patients with early diabetic nephropathy has important diagnostic value.

  16. Neuroprotective action of N-acetyl serotonin in oxidative stress-induced apoptosis through the activation of both TrkB/CREB/BDNF pathway and Akt/Nrf2/Antioxidant enzyme in neuronal cells

    Directory of Open Access Journals (Sweden)

    Jae-Myung Yoo

    2017-04-01

    Full Text Available N-acetyl serotonin (NAS as a melatonin precursor has neuroprotective actions. Nonetheless, it is not clarified how NAS protects neuronal cells against oxidative stress. Recently, we have reported that N-palmitoyl serotonins possessed properties of antioxidants and neuroprotection. Based on those, we hypothesized that NAS, a N-acyl serotonin, may have similar actions in oxidative stress-induced neuronal cells, and examined the effects of NAS based on in vitro and in vivo tests. NAS dose-dependently inhibited oxidative stress-induced cell death in HT-22 cells. Moreover, NAS suppressed glutamate-induced apoptosis by suppressing expression of AIF, Bax, calpain, cytochrome c and cleaved caspase-3, whereas it enhanced expression of Bcl-2. Additionally, NAS improved phosphorylation of tropomyosin-related kinase receptor B (TrkB and cAMP response element-binding protein (CREB as well as expression of brain-derived neurotrophic factor (BDNF, whereas the inclusion of each inhibitor of JNK, p38 or Akt neutralized the neuroprotective effect of NAS, but not that of ERK. Meanwhile, NAS dose-dependently reduced the level of reactive oxygen species, and enhanced the level of glutathione in glutamate-treated HT-22 cells. Moreover, NAS significantly increased expression of heme oxygenase-1, NAD(PH quinine oxidoreductase-1 and glutamate-cysteine ligase catalytic subunit as well as nuclear translocation of NF-E2-related factor-2. Separately, NAS at 30 mg/kg suppressed scopolamine-induced memory impairment and cell death in CA1 and CA3 regions in mice. In conclusion, NAS shows actions of antioxidant and anti-apoptosis by activating TrkB/CREB/BDNF pathway and expression of antioxidant enzymes in oxidative stress-induced neurotoxicity. Therefore, such effects of NAS may provide the information for the application of NAS against neurodegenerative diseases.

  17. Novel cytochrome p450 bioactivation of a terminal phenyl acetylene group: formation of a one-carbon loss benzaldehyde and other oxidative products in the presence of N-acetyl cysteine or glutathione.

    Science.gov (United States)

    Subramanian, Raju; Tam, Janet; Aidasani, Divesh; Reid, Darren L; Skiles, Gary L

    2011-05-16

    Compounds 1 (N1-(3-ethynylphenyl)-6-methyl-N5-(3-(6-(methylamino)pyrimidin-4-yl)pyridin-2-yl) isoquinoline-1,5-diamine) and 2 (N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine; Erlotinib/Tarceva) are kinase inhibitors that contain a terminal phenyl acetylene moiety. When incubated in the presence of P450 and NADPH, the anticipated phenyl acetic acid metabolite was formed. When 10 mM of N-acetyl-l-cysteine was added to the incubation mixtures, the phenyl acetic acid product was reduced and at 25 mM or higher concentration of NAC, formation of the phenyl acetic acid was abolished. Instead, the phenyl acetylene moiety lost a carbon and formed a benzaldehyde product. Other oxidation products incorporating one or more equivalents of NAC were also observed. The identities of the metabolites were characterized by MS and NMR. Addition of deferoxamine or ascorbic acid diminished the formation of the NAC influenced products. Similar products were also observed when 1 or 2 were incubated in P450 reactions supplemented with GSH, in Fenton reactions supplemented with NAC or GSH, and in peroxidase reactions supplemented with NAC. We propose the thiols act as a pro-oxidant readily undergoing a one-electron oxidation to form thiyl radicals which in turn initiates the formation of other peroxy radicals that drive the reaction to the observed products. These in vitro findings suggest that one-electron oxidation of thiols may promote the cooxidation of xenobiotic substrates.

  18. Pharmacogenetics of azathioprine in inflammatory bowel disease: a role for glutathione-S-transferase?

    Science.gov (United States)

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

    2014-04-01

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

  19. Lean consumption.

    Science.gov (United States)

    Womack, James P; Jones, Daniel T

    2005-03-01

    During the past 20 years, the real price of most consumer goods has fallen worldwide, the variety of goods and the range of sales channels offering them have continued to grow, and product quality has steadily improved. So why is consumption often so frustrating? It doesn't have to be--and shouldn't be--the authors say. They argue that it's time to apply lean thinking to the processes of consumption--to give consumers the full value they want from goods and services with the greatest efficiency and the least pain. Companies may think they save time and money by off-loading work to the consumer but, in fact, the opposite is true. By streamlining their systems for providing goods and services, and by making it easier for customers to buy and use those products and services, a growing number of companies are actually lowering costs while saving everyone time. In the process, these businesses are learning more about their customers, strengthening consumer loyalty, and attracting new customers who are defecting from less user-friendly competitors. The challenge lies with the retailers, service providers, manufacturers, and suppliers that are not used to looking at total cost from the standpoint of the consumer and even less accustomed to working with customers to optimize the consumption process. Lean consumption requires a fundamental shift in the way companies think about the relationship between provision and consumption, and the role their customers play in these processes. It also requires consumers to change the nature of their relationships with the companies they patronize. Lean production has clearly triumphed over similar obstacles in recent years to become the dominant global manufacturing model. Lean consumption, its logical companion, can't be far behind.

  20. The significance of urine N-acetyl-beta-D-glucosaminidase in kidney injuy with patients acute paraquat poisoning%尿中N-乙酰-β-D-氨基葡萄糖苷酶活力对急性百草枯中毒早期肾损伤的意义

    Institute of Scientific and Technical Information of China (English)

    施旭斌; 何俊玲; 陆远强

    2013-01-01

    Objectives To test the hypothesis that urine N-acetyl-beta-D-glucosaminidase (NAG) is an early biomarker for acute kidney injury in patients with acute paraquat poisoning.Methods Forty-four patients with paraquat intoxication and 40 age and gender-matched healthy control participants were recruited.The urine N-acetyl-beta-D-glucosaminidase was determined by spectrophotometric methods.Results The urine Nacetyl-beta-D-glucosaminidase activities in the patients with paraquat poisoning were higher than the corresponding values in the control participants (P<0.01); The prevalence rate of mortality was significantly higher in subjects with N-acetyl-beta-D-glucosaminidase activities ≥25 U/g Cr than in those N-acetyl-beta-Dglucosaminidase activities <25 U/g Cr (34.4% vs 16.7%,P<0.01).Conclusions The urine N-acetyl-beta-Dglucosaminidase could be used as an early biomarker for acute kidney injury and predictor of mortality in patients with acute paraquat intoxication.%目的 探讨尿中N-乙酰-β-D-氨基葡萄糖苷酶(NAG)活力在急性百草枯中毒早期肾损害中的意义.方法 检测44例急性百草枯患者人院后尿中NAG活力并与40例健康对照组进行比较.结果百草枯中毒组尿中NAG活力为(40.7±10.6) U/g Cr明显高于健康对照组[(18.6±5.1) U/g Cr],差异有统计学意义(P<0.01).NAG活力≥25 U/g Cr中毒组30 d死亡率(34.4%)明显高于NAG活力<25 U/gCr组(16.7%),两组病死率的差异有统计学意义(P<0.01).结论 尿中NAG活力≥25 U/g Cr组百草枯中毒病死率明显升高,尿中NAG活力对急性百草枯中毒早期肾损伤诊断可能有一定意义.

  1. Unsustainable Consumption

    DEFF Research Database (Denmark)

    Thøgersen, John

    2014-01-01

    , research on the root causes of environmentally harmful human behavior is reviewed. Why is there no satiation of consumption in sight, even in the most affluent countries, and why do people continue to make choices that are known to be environmentally harmful? While potentially catastrophic, the harms from...

  2. Flexible Consumption

    DEFF Research Database (Denmark)

    Holm Jacobsen, Peter; Pallesen, Trine

    This report presents the first findings from our qualitative study of consumer behaviour vis-à-vis flexible consumption. The main of objective of this report is to present our first round of data from Bornholm, and to assist the design of products/services designed in WP6. In the report, we adopt...

  3. Rational design of an organometallic glutathione transferase inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Ang, W.H.; Parker, L.J.; De Luca, A.; Juillerat-Jeanneret, L.; Morton, C.J.; LoBello, M.; Parker, M.W.; Dyson, P.J.; (ISIC)

    2010-08-17

    A hybrid organic-inorganic (organometallic) inhibitor was designed to target glutathione transferases. The metal center is used to direct protein binding, while the organic moiety acts as the active-site inhibitor. The mechanism of inhibition was studied using a range of biophysical and biochemical methods.

  4. Interaction of pleuromutilin derivatives with the ribosomal peptidyl transferase center

    DEFF Research Database (Denmark)

    Long, K. S.; Hansen, L. K.; Jakobsen, L.;

    2006-01-01

    Tiamulin is a pleuromutilin antibiotic that is used in veterinary medicine. The recently published crystal structure of a tiamulin-50S ribosomal subunit complex provides detailed information about how this drug targets the peptidyl transferase center of the ribosome. To promote rational design...

  5. Homogentisate solanesyl transferase (HST) cDNA’s in maize

    Science.gov (United States)

    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 ...

  6. Production of N-acetylgalactosaminyl-transferase 2 (GalNAc-T2) fused with secretory signal Igκ in insect cells.

    Science.gov (United States)

    Horynová, Milada; Takahashi, Kazuo; Hall, Stacy; Renfrow, Matthew B; Novak, Jan; Raška, Milan

    2012-02-01

    The human UDP-N-acetyl-α-d-galactosamine:polypeptide N-acetylgalactosaminyl-transferase 2 (GalNAc-T2) is one of the key enzymes that initiate synthesis of hinge-region O-linked glycans of human immunoglobulin A1 (IgA1). We designed secreted soluble form of human GalNAc-T2 as a fusion protein containing mouse immunoglobulin light chain kappa secretory signal and expressed it using baculovirus and mammalian expression vectors. The recombinant protein was secreted by insect cells Sf9 and human HEK 293T cells in the culture medium. The protein was purified from the media using affinity Ni-NTA chromatography followed by stabilization of purified protein in 50mM Tris-HCl buffer at pH 7.4. Although the purity of recombinant GalNAc-T2 was comparable in both expression systems, the yield was higher in Sf9 insect expression system (2.5mg of GalNAc-T2 protein per 1L culture medium). The purified soluble recombinant GalNAc-T2 had an estimated molecular mass of 65.8kDa and its amino-acid sequence was confirmed by mass-spectrometric analysis. The enzymatic activity of Sf9-produced recombinant GalNAc-T2 was determined by the quantification of enzyme-mediated attachment of GalNAc to synthetic IgA1 hinge-region peptide as the acceptor and UDP-GalNAc as the donor. In conclusion, murine immunoglobulin kappa secretory signal was used for production of secreted enzymatically active GalNAc-T2 in insect baculovirus expression system.

  7. Potential in vivo amelioration by N-acetyl-L-cysteine of oxidative stress in brain in human double mutant APP/PS-1 knock-in mice: toward therapeutic modulation of mild cognitive impairment.

    Science.gov (United States)

    Huang, Quanzhen; Aluise, Christopher D; Joshi, Gururaj; Sultana, Rukhsana; St Clair, Daret K; Markesbery, William R; Butterfield, D Allan

    2010-09-01

    Alzheimer's disease (AD) is the most prevalent form of dementia among the elderly. Although the underlying cause has yet to be established, numerous data have shown that oxidative stress is implicated in AD as well as in preclinical stages of AD, such as mild cognitive impairment (MCI). The oxidative stress observed in brains of subjects with AD and MCI may be due, either fully or in part, to increased free radicals mediated by amyloid-beta peptide (Abeta). By using double human mutant APP/PS-1 knock-in mice as the AD model, the present work demonstrates that the APP/PS-1 double mutation results in elevated protein oxidation (as indexed by protein carbonyls), protein nitration (as indexed by 3-nitrotyrosine), as well as lipid peroxidation (as indexed by protein-bound 4-hydroxy-2-nonenal) in brains of mice aged 9 months and 12 months. APP/PS-1 mice also exhibited lower levels of brain glutathione peroxidase (GPx) in both age groups studied, whereas glutathione reductase (GR) levels in brain were unaffected by the mutation. The activities of both of these antioxidant enzymes were significantly decreased in APP/PS-1 mouse brains, whereas the activity of glucose-6-phosphate dehydrogenase (G6PDH) was increased relative to controls in both age groups. Levels of peptidyl prolyl isomerase 1 (Pin1) were significantly decreased in APP/PS-1 mouse brain aged 9 and 12 months. Administration of N-acetyl-L-cysteine (NAC), a glutathione precursor, to APP/PS-1 mice via drinking water suppressed increased protein oxidation and nitration and also significantly augmented levels and activity of GPx in brain from both age groups. Oral administration of NAC also increased the diminished activity of GR and protected against lipid peroxidation in brains of 9-month-old APP/PS-1 mice only. Pin1 levels, GR levels, and G6PDH activity in brain were unaffected by oral administration of NAC in both age groups. These results are discussed with reference to the therapeutic potential of this brain

  8. Collaborative Consumption

    DEFF Research Database (Denmark)

    Gjerdrum Pedersen, Esben Rahbek; Netter, Sarah

    2015-01-01

    Purpose – The purpose of this paper is to explore barriers and opportunities for business models based on the ideas of collaborative consumption within the fashion industry. Design/methodology/approach – The analysis is based on a multiple-case study of Scandinavian fashion libraries – a new......, clothes-sharing concept that has emerged as a fashion niche within the last decade. Findings – It is concluded that fashion libraries offers interesting perspectives, e.g. by allowing people to experiment with styles without having to pay the full cost and becoming a meeting place for young designers...... and end consumers. However, at present fashion libraries remain a small-scale phenomenon with difficulties reaching the mainstream market, not least due to limited financial and human resources as well as conventional fashion consumption patterns. Research limitations/implications – The study is limited...

  9. Collaborative Consumption

    DEFF Research Database (Denmark)

    Gjerdrum Pedersen, Esben Rahbek; Netter, Sarah

    Purpose: The purpose of this paper is to explore barriers and opportunities for business models based on the ideas of collaborative consumption within the fashion industry. Design/methodology/approach: The analysis is based on a multiple-­‐‑case study of Scandinavian fashion libraries – a new......, clothes-­‐‑sharing concept that has emerged as a fashion niche within the last decade. Findings: It is concluded that fashion libraries offers interesting perspectives, e.g. by allowing people to experiment with styles without having to pay the full cost and becoming a meeting place for young designers...... and end consumers. However, at present fashion libraries remain a small-­‐‑scale phenomenon with difficulties reaching the mainstream market, not least due to limited financial and human resources as well as conventional fashion consumption patterns. Research limitations/implications: The study is limited...

  10. Positioning consumption

    DEFF Research Database (Denmark)

    Halkier, Bente; Keller, Margit

    2014-01-01

    positionings emerges based on empirical examples of research in parent–children consumption. Positionings are flexible discursive fixations of the relationship between the performances of the practitioner, other practitioners, media discourse and consumption activities. The basic positioning types...... are the practice maintenance and the practice change position, with different sorts of adapting in between. Media discourse can become a resource for a resistant position against social control or for an appropriating position in favour of space for action. Regardless of the current relation to a particular media...... discourse, practitioners attempt to maintain their self-positioning of competence when performing. This leads us, as researchers, to caution against any a priori anticipation of the anchoring power of media discourses within everyday activities....

  11. Transdisciplinary Consumption

    Directory of Open Access Journals (Sweden)

    Sue L.T. McGregor

    2013-06-01

    Full Text Available For the past 100 years, research about consumption has stemmed from two main disciplines: (a consumer studies/consumer sciences (including consumer policy and education (a spin off from home economics and (b consumer behaviour research (a spin off from marketing. This paper focuses on these two disciplines because the results of their respective research are used to shape consumer policy and consumer protection legislation and regulations, marketplace competition policy and regulations, consumer product and service information, media coverage of consumer issues, consumer education curricula and pedagogy, and insights into an evolving consumer culture. This paper asks consumer studies/sciences and consumer behaviour scholars to embrace the transdisciplinary methodology in addition to the traditional empirical, interpretive and critical methodologies. It provides an overview of the four axioms of transdisciplinary methodology with examples to illustrate how consumer-related research would change to address the complex reality of 21st century consumption.

  12. Substrate specificities of three members of the human UDP-N-acetyl-alpha-D-galactosamine:Polypeptide N-acetylgalactosaminyltransferase family, GalNAc-T1, -T2, and -T3

    DEFF Research Database (Denmark)

    Wandall, H H; Hassan, H; Mirgorodskaya, E

    1997-01-01

    recombinant GalNAc-transferases. GalNAc-T1, -T2, and -T3 were expressed as soluble proteins in insect cells and purified to near homogeneity. The enzymes have distinct but partly overlapping specificities with short peptide acceptor substrates. Peptides specifically utilized by GalNAc-T2 or -T3......, or preferentially by GalNAc-T1 were identified. GalNAc-T1 and -T3 showed strict donor substrate specificities for UDP-GalNAc, whereas GalNAc-T2 also utilized UDP-Gal with one peptide acceptor substrate. Glycosylation of peptides based on MUC1 tandem repeat showed that three of five potential sites in the tandem...... repeat were glycosylated by all three enzymes when one or five repeat peptides were analyzed. However, analysis of enzyme kinetics by capillary electrophoresis and mass spectrometry demonstrated that the three enzymes react at different rates with individual sites in the MUC1 repeat. The results...

  13. Proton mobilities in crambin and glutathione S-transferase

    Science.gov (United States)

    Wanderlingh, U. N.; Corsaro, C.; Hayward, R. L.; Bée, M.; Middendorf, H. D.

    2003-08-01

    Using a neutron backscattering spectrometer, the temperature dependence of mean-square atomic displacements derived from window-integrated quasielastic spectra was measured for two D 2O-hydrated proteins: crambin and glutathione S-transferase. Analyses show that the anharmonic dynamics observed around and above 200 K is consistent with a description in terms of proton/deuteron jumps within asymmetric double-minimum potentials. Also determined were activation energies along with estimates of effective masses and average oscillator energies.

  14. Interaction of pleuromutilin derivatives with the ribosomal peptidyl transferase center

    DEFF Research Database (Denmark)

    Long, K. S.; Hansen, L. K.; Jakobsen, L.

    2006-01-01

    are similarly anchored in the binding pocket by the common tricyclic mutilin core. However, varying effects are observed at U2584 and U2585, indicating that the side chain extensions adopt distinct conformations within the cavity and thereby affect the rRNA conformation differently. An Escherichia coli L3...... site. The data suggest that pleuromutilin drugs with enhanced antimicrobial activity may be obtained by maximizing the number of interactions between the side chain moiety and the peptidyl transferase cavity....

  15. [Glutathione S-transferase of alpha class from pike liver].

    Science.gov (United States)

    Borvinskaia, E V; Smirnov, L P; Nemova, N N

    2013-01-01

    In this study, glutathione S-transferase (GST) was isolated from the liver of pike Esox lucius, which was homogenous according to SDS-PAGE and isoelectrofocusing. It is a homodimer with subunits mass 25235.36 Da (according to HPLC-MS/MS) and pI about 6.4. Substrate specificity, thermostability, some kinetic characteristics and optimum pH were determined. The enzyme was identified as Alpha class GST.

  16. Bioinformatic analysis of an unusual gene-enzyme relationship in the arginine biosynthetic pathway among marine gamma proteobacteria: implications concerning the formation of N-acetylated intermediates in prokaryotes

    Directory of Open Access Journals (Sweden)

    Labedan Bernard

    2006-01-01

    Full Text Available Abstract Background The N-acetylation of L-glutamate is regarded as a universal metabolic strategy to commit glutamate towards arginine biosynthesis. Until recently, this reaction was thought to be catalyzed by either of two enzymes: (i the classical N-acetylglutamate synthase (NAGS, gene argA first characterized in Escherichia coli and Pseudomonas aeruginosa several decades ago and also present in vertebrates, or (ii the bifunctional version of ornithine acetyltransferase (OAT, gene argJ present in Bacteria, Archaea and many Eukaryotes. This paper focuses on a new and surprising aspect of glutamate acetylation. We recently showed that in Moritella abyssi and M. profunda, two marine gamma proteobacteria, the gene for the last enzyme in arginine biosynthesis (argH is fused to a short sequence that corresponds to the C-terminal, N-acetyltransferase-encoding domain of NAGS and is able to complement an argA mutant of E. coli. Very recently, other authors identified in Mycobacterium tuberculosis an independent gene corresponding to this short C-terminal domain and coding for a new type of NAGS. We have investigated the two prokaryotic Domains for patterns of gene-enzyme relationships in the first committed step of arginine biosynthesis. Results The argH-A fusion, designated argH(A, and discovered in Moritella was found to be present in (and confined to marine gamma proteobacteria of the Alteromonas- and Vibrio-like group. Most of them have a classical NAGS with the exception of Idiomarina loihiensis and Pseudoalteromonas haloplanktis which nevertheless can grow in the absence of arginine and therefore appear to rely on the arg(A sequence for arginine biosynthesis. Screening prokaryotic genomes for virtual argH-X 'fusions' where X stands for a homologue of arg(A, we retrieved a large number of Bacteria and several Archaea, all of them devoid of a classical NAGS. In the case of Thermus thermophilus and Deinococcus radiodurans, the arg(A-like sequence

  17. Determination of Activity of the Enzymes Hypoxanthine Phosphoribosyl Transferase (HPRT) and Adenine Phosphoribosyl Transferase (APRT) in Blood Spots on Filter Paper.

    Science.gov (United States)

    Auler, Kasie; Broock, Robyn; Nyhan, William L

    2015-07-01

    Hypoxanthine-guanine phosphoribosyl-transferase (HPRT) deficiency is the cause of Lesch-Nyhan disease. Adenine phosphoribosyl-transferase (APRT) deficiency causes renal calculi. The activity of each enzyme is readily determined on spots of whole blood on filter paper. This unit describes a method for detecting deficiencies of HPRT and APRT. Copyright © 2015 John Wiley & Sons, Inc.

  18. Prevention of IcaA regulated poly N-acetyl glucosamine formation in Staphylococcus aureus biofilm through new-drug like inhibitors: In silico approach and MD simulation study.

    Science.gov (United States)

    Gupta, Ayushi; Mishra, Swechha; Singh, Sangeeta; Mishra, Sonali

    2017-09-01

    The effectiveness of various ligands against the protein structure of IcaA of the IcaABCD gene locus of Staphylococcus aureus were examined using the approach of structure based drug designing in reference with the protein's efficiency to form biofilms. Four compounds CID42738592, CID90468752, CID24277882, and CID6435208 were secluded from a database of 31,242 inhibitory ligands on the justification of the evaluated values falling under the four - tier structure based virtual screening. Under this principle value of least binding energy, human oral absorption and ADME properties were taken into consideration. Using the Glide module of Schrödinger, the above mentioned ligands showed an effective action against the protein IcaA which showed reduced activity as a glucosaminyl transferase. The complex of protein and ligand with best docking score was chosen for simulation studies. Structure based drug designing for the protein IcaA has given us potential leads as anti - biofilm agents. These screened out ligands might enable the development of new therapeutic strategies aimed at disrupting Staphylococcus aureus biofilms. The complex was showing stability towards the end of time for which it has been put for simulation. Thus molecule could be considered for making of biofilms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Human cytosolic glutathione transferases: structure, function, and drug discovery.

    Science.gov (United States)

    Wu, Baojian; Dong, Dong

    2012-12-01

    Glutathione transferases (GSTs) are important detoxifying enzymes that catalyze the conjugation of electrophilic substrates to glutathione. In recent years, GSTs have been of great interest in pharmacology and drug development because of their involvement in many important biological processes such as steroid and prostaglandin biosynthesis, tyrosine catabolism, and cell apoptosis. This review describes crystal structures for cytosolic GSTs and correlates active-site features with enzyme functions (e.g., steroid synthesis, tyrosine degradation, and dehydroascorbate reduction) and substrate selectivity. Use of these crystal structures for the design of specific inhibitors for several GST enzymes is also discussed.

  20. Cholesterol oxides inhibit cholesterol esterification by lecithin: cholesterol acyl transferase

    Directory of Open Access Journals (Sweden)

    Eder de Carvalho Pincinato

    2009-09-01

    Full Text Available Cholesterol oxides are atherogenic and can affect the activity of diverse important enzymes for the lipidic metabolism. The effect of 7β-hydroxycholesterol, 7-ketocholesterol, 25-hydroxycholesterol, cholestan-3β,5α,6β-triol,5,6β-epoxycholesterol, 5,6α-epoxycholesterol and 7α-hydroxycholesterol on esterification of cholesterol by lecithin:cholesterol acyl transferase (LCAT, EC 2.3.1.43 and the transfer of esters of cholesterol oxides from high density lipoprotein (HDL to low density lipoproteins (LDL and very low density lipoproteins (VLDL by cholesteryl ester transfer protein (CETP was investigated. HDL enriched with increasing concentrations of cholesterol oxides was incubated with fresh plasma as source of LCAT. Cholesterol and cholesterol oxides esterification was followed by measuring the consumption of respective free sterol and oxysterols. Measurements of cholesterol and cholesterol oxides were done by gas-chromatography. 14C-cholesterol oxides were incorporated into HDL2 and HDL3 subfractions and then incubated with fresh plasma containing LCAT and CETP. The transfer of cholesterol oxide esters was followed by measuring the 14C-cholesterol oxide-derived esters transferred to LDL and VLDL. All the cholesterol oxides studied were esterified by LCAT after incorporation into HDL particles, competing with cholesterol by LCAT. Cholesterol esterification by LCAT was inversely related to the cholesterol oxide concentration. The esterification of 14C-cholesterol oxides was higher in HDL3 and the transfer of the derived esters was greater from HDL2 to LDL and VLDL. The results suggest that cholesterol esterification by LCAT is inhibited in cholesterol oxide-enriched HDL particles. Moreover, the cholesterol oxides-derived esters are efficiently transferred to LDL and VLDL. Therefore, we suggest that cholesterol oxides may exert part of their atherogenic effect by inhibiting cholesterol esterification on the HDL surface and thereby disturbing

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

    Science.gov (United States)

    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....

  2. Electrochemical evaluation of glutathione S-transferase kinetic parameters.

    Science.gov (United States)

    Enache, Teodor Adrian; Oliveira-Brett, Ana Maria

    2015-02-01

    Glutathione S-transferases (GSTs), are a family of enzymes belonging to the phase II metabolism that catalyse the formation of thioether conjugates between the endogenous tripeptide glutathione and xenobiotic compounds. The voltammetric behaviour of glutathione (GSH), 1-chloro-2,4-dinitrobenzene (CDNB) and glutathione S-transferase (GST), as well as the catalytic conjugation reaction of GSH to CDNB by GST was investigated at room temperature, T=298.15K (25°C), at pH6.5, for low concentration of substrates and enzyme, using differential pulse (DP) voltammetry at a glassy carbon electrode. Only GSH can be oxidized; a sensitivity of 0.14nA/μM and a LOD of 6.4μM were obtained. The GST kinetic parameter electrochemical evaluation, in relation to its substrates, GSH and CDNB, using reciprocal Michaelis-Menten and Lineweaver-Burk double reciprocal plots, was determined. A value of KM~100μM was obtained for either GSH or CDNB, and Vmax varied between 40 and 60μmol/min per mg of GST.

  3. A novel method for screening the glutathione transferase inhibitors

    Directory of Open Access Journals (Sweden)

    Węgrzyn Grzegorz

    2009-03-01

    Full Text Available Abstract Background Glutathione transferases (GSTs belong to the family of Phase II detoxification enzymes. GSTs catalyze the conjugation of glutathione to different endogenous and exogenous electrophilic compounds. Over-expression of GSTs was demonstrated in a number of different human cancer cells. It has been found that the resistance to many anticancer chemotherapeutics is directly correlated with the over-expression of GSTs. Therefore, it appears to be important to find new GST inhibitors to prevent the resistance of cells to anticancer drugs. In order to search for glutathione transferase (GST inhibitors, a novel method was designed. Results Our results showed that two fragments of GST, named F1 peptide (GYWKIKGLV and F2 peptide (KWRNKKFELGLEFPNL, can significantly inhibit the GST activity. When these two fragments were compared with several known potent GST inhibitors, the order of inhibition efficiency (measured in reactions with 2,4-dinitrochlorobenzene (CDNB and glutathione as substrates was determined as follows: tannic acid > cibacron blue > F2 peptide > hematin > F1 peptide > ethacrynic acid. Moreover, the F1 peptide appeared to be a noncompetitive inhibitor of the GST-catalyzed reaction, while the F2 peptide was determined as a competitive inhibitor of this reaction. Conclusion It appears that the F2 peptide can be used as a new potent specific GST inhibitor. It is proposed that the novel method, described in this report, might be useful for screening the inhibitors of not only GST but also other enzymes.

  4. The omega-class glutathione transferases: structure, function, and genetics.

    Science.gov (United States)

    Board, Philip G

    2011-05-01

    The omega class of glutathione transferases (GSTs) is a relatively ancient member of the cytosolic GST superfamily, and the omega-class GSTs are found in plants, animals, and some microbial species. The omega-class GSTs exhibit the canonical GST fold, but, unlike other GSTs, the omega-class GSTs have a cysteine residue in their active site. Consequently, the omega-class GSTs catalyze a range of thiol transferase and reduction reactions that are not catalyzed by members of the other classes. Human GSTO1-1 can catalyze the reduction of monomethylarsonic acid (V), but this does not appear to be physiologically important in cases of high environmental arsenic exposure. GSTO1-1 also plays an important role in the biotransformation of reactive α-haloketones to nontoxic acetophenones. Genetic variation is common in the omega-class GST genes, and variants that result in deficiency of GSTO1-1 have been characterized. Genetic linkage studies have discovered associations between GSTO genes and the age at onset of Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. The mechanism underlying this association with neurological disease may derive from the capacity of omega-class GSTs to mitigate oxidative stress or their role in activating the proinflammatory cytokine, interleukin-1β.

  5. A glutathione s-transferase confers herbicide tolerance in rice

    Directory of Open Access Journals (Sweden)

    Tingzhang Hu

    2014-07-01

    Full Text Available Plant glutathione S-transferases (GSTs have been a focus of attention due to their role in herbicide detoxification. OsGSTL2 is a glutathione S-transferase, lambda class gene from rice (Oryza sativa L.. Transgenic rice plants over-expressing OsGSTL2 were generated from rice calli by the use of an Agrobacterium transformation system, and were screened by a combination of hygromycin resistance, PCR and Southern blot analysis. In the vegetative tissues of transgenic rice plants, the over-expression of OsGSTL2 not only increased levels of OsGSTL2 transcripts, but also GST and GPX expression, while reduced superoxide. Transgenic rice plants also showed higher tolerance to glyphosate and chlorsulfuron, which often contaminate agricultural fields. The findings demonstrate the detoxification role of OsGSTL2 in the growth and development of rice plants. It should be possible to apply the present results to crops for developing herbicide tolerance and for limiting herbicide contamination in the food chain.

  6. Acrolein-detoxifying isozymes of glutathione transferase in plants.

    Science.gov (United States)

    Mano, Jun'ichi; Ishibashi, Asami; Muneuchi, Hitoshi; Morita, Chihiro; Sakai, Hiroki; Biswas, Md Sanaullah; Koeduka, Takao; Kitajima, Sakihito

    2017-02-01

    Acrolein is a lipid-derived highly reactive aldehyde, mediating oxidative signal and damage in plants. We found acrolein-scavenging glutathione transferase activity in plants and purified a low K M isozyme from spinach. Various environmental stressors on plants cause the generation of acrolein, a highly toxic aldehyde produced from lipid peroxides, via the promotion of the formation of reactive oxygen species, which oxidize membrane lipids. In mammals, acrolein is scavenged by glutathione transferase (GST; EC 2.5.1.18) isozymes of Alpha, Pi, and Mu classes, but plants lack these GST classes. We detected the acrolein-scavenging GST activity in four species of plants, and purified an isozyme showing this activity from spinach (Spinacia oleracea L.) leaves. The isozyme (GST-Acr), obtained after an affinity chromatography and two ion exchange chromatography steps, showed the K M value for acrolein 93 μM, the smallest value known for acrolein-detoxifying enzymes in plants. Peptide sequence homology search revealed that GST-Acr belongs to the GST Tau, a plant-specific class. The Arabidopsis thaliana GST Tau19, which has the closest sequence similar to spinach GST-Acr, also showed a high catalytic efficiency for acrolein. These results suggest that GST plays as a scavenger for acrolein in plants.

  7. Characterization of glutathione S-transferase of Taenia solium.

    Science.gov (United States)

    Vibanco-Pérez, N; Jiménez, L; Merchant, M T; Landa, A

    1999-06-01

    A Taenia solium glutathione-S-transferase fraction (SGSTF) was isolated from a metacestode crude extract by affinity chromatography on reduced glutathione (GSH)-sepharose. The purified fraction displayed a specific glutathione S-transferase (GST) activity of 2.8 micromol/min/mg and glutathione peroxidase selenium-independent activity of 0.22 micromol/min/mg. Enzymatic characterization of the fraction suggested that the activity was closer to the mammalian mu-class GSTs. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis, gel filtration, and enzyme activity analysis showed that the fraction was composed of a major band of Mr = 26 kd and that the active enzyme was dimeric. Immunohistochemical studies using specific antibodies against the major 26-kd band of the SGSTF indicated that GST protein was present in the tegument, parenchyma, protonephridial, and tegumentary cytons of the T. solium metacestode. Antibodies generated against the SGSTF tested in western blot showed cross-reactivity against GSTs purified from Taenia saginata, T. taeniaeformis, and T. crassiceps, but did not react with GSTs from Schistosoma mansoni, or mice, rabbit, and pig liver tissue. Furthermore, immunization of mice with SGSTF reduced the metacestode burden up to 74.2%. Our findings argue in favor of GST having an important role in the survival of T. solium in its hosts.

  8. Hepatic cytochrome P450 and UDP-glucuronosyl transferase are affected by five sources of dietary fiber in germ-free rats.

    Science.gov (United States)

    Nugon-Baudon, L; Roland, N; Flinois, J P; Beaune, P

    1996-02-01

    The influence of dietary fiber on xenobiotic-metabolizing enzymes (XME) was assessed using germ-free rats fed inulin and other sources of fiber (wheat bran, carrot, cocoa and oat). The consumption of cocoa fiber greatly modified the hepatic cytochrome P450 isoenzymatic profile, causing a strong enhancement of 1A2 and 2B1/B2 forms, concomitant with a significant decrease of the constitutive form 2C11, compared with all of the other types of fiber. Moreover, rats fed the cocoa fiber diet had a higher specific activity of hepatic UDP-glucuronosyl transferase than their carrot fiber- and wheat bran-fed counterparts. Intestinal UDP-glucuronosyl transferase was unaffected by the type of ingested fiber. Diet composition also did not alter the specific activity of glutathione-S-transferase in the liver, small intestine, or colon. Using earlier results obtained in heteroxenic rats, we show that intestinal microflora plays a key role in some of the effects of fiber on XME, although this is not a necessary prerequisite for all of the liver alterations.

  9. Thermodynamics of Enzyme-Catalyzed Reactions: Part 2. Transferases

    Science.gov (United States)

    Goldberg, Robert N.; Tewari, Yadu B.

    1994-07-01

    Equilibrium constants and enthalpy changes for reactions catalyzed by the transferase class of enzymes have been compiled. For each reaction the following information is given: the reference for the data; the reaction studied; the name of the enzyme used and its Enzyme Commission number; the method of measurement; the conditions of measurement [temperature, pH, ionic strength, and the buffer(s) and cofactor(s) used]; the data and an evaluation of it; and, sometimes, commentary on the data and on any corrections which have been applied to it or any calculations for which the data have been used. The data from 285 references have been examined and evaluated. Chemical Abstract Service registry numbers are given for the substances involved in these various reactions. There is a cross reference between the substances and the Enzyme Commission numbers of the enzymes used to catalyze the reactions in which the substances participate.

  10. Pleiotropic functions of glutathione S-transferase P.

    Science.gov (United States)

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

    2014-01-01

    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.

  11. Ghrelin O-Acyl Transferase: Bridging Ghrelin and Energy Homeostasis

    Directory of Open Access Journals (Sweden)

    Andrew Shlimun

    2011-01-01

    Full Text Available Ghrelin O-acyl transferase (GOAT is a recently identified enzyme responsible for the unique n-acyl modification of ghrelin, a multifunctional metabolic hormone. GOAT structure and activity appears to be conserved from fish to man. Since the acyl modification is critical for most of the biological actions of ghrelin, especially metabolic functions, GOAT emerged as a very important molecule of interest. The research on GOAT is on the rise, and several important results reiterating its significance have been reported. Notable among these discoveries are the identification of GOAT tissue expression patterns, effects on insulin secretion, blood glucose levels, feeding, body weight, and metabolism. Several attempts have been made to design and test synthetic compounds that can modulate endogenous GOAT, which could turn beneficial in favorably regulating whole body energy homeostasis. This paper will focus to provide an update on recent advances in GOAT research and its broader implications in the regulation of energy balance.

  12. Glutathione analogue sorbents selectively bind glutathione S-transferase isoenzymes.

    Science.gov (United States)

    Castro, V M; Kelley, M K; Engqvist-Goldstein, A; Kauvar, L M

    1993-06-01

    Novel affinity sorbents for glutathione S-transferases (GSTs) were created by binding glutathione (GSH) analogues to Sepharose 6B. The GSH molecule was modified at the glycine moiety and at the group attached to the sulphur of cysteine. When tested by affinity chromatography in a flow-through microplate format, several of these sorbents selectively bound GST isoenzymes. gamma E-C(Hx)-phi G (glutathione with a hexyl moiety bound to cysteine and phenylglycine substituted for glycine) specifically bound rat GST 7-7, the Pi-class isoenzyme, from liver, kidney and small intestine. gamma E-C(Bz)-beta A (benzyl bound to cysteine and beta-alanine substituted for glycine) was highly selective for rat subunits 3 and 4, which are Mu-class isoenzymes. By allowing purification of the isoenzymes under mild conditions that preserve activity, the novel sorbents should be useful in characterizing the biological roles of GSTs in both normal animal and cancer tissues.

  13. Experimental conditions affecting functional comparison of highly active glutathione transferases.

    Science.gov (United States)

    Fedulova, Natalia; Mannervik, Bengt

    2011-06-01

    Glutathione transferases (GSTs, EC 2.5.1.18) possess multiple functions and have potential applications in biotechnology. Direct evidence of underestimation of activity of human GST A3-3 and porcine GST A2-2 measured at submicromolar enzyme concentrations is reported here for the first time. The combination of time-dependent and enzyme concentration-dependent loss of activity and the choice of the organic solvent for substrates were found to cause irreproducibility of activity measurements of GSTs. These effects contribute to high variability of activity values of porcine GST A2-2 and human Alpha-class GSTs reported in the literature. Adsorption of GSTs to surfaces was found to be the main explanation of the observed phenomena. Several approaches to improved functional comparison of highly active GSTs are proposed.

  14. From glutathione transferase to pore in a CLIC

    CERN Document Server

    Cromer, B A; Morton, C J; Parker, M W; 10.1007/s00249-002-0219-1

    2002-01-01

    Many plasma membrane chloride channels have been cloned and characterized in great detail. In contrast, very little is known about intracellular chloride channels. Members of a novel class of such channels, called the CLICs (chloride intracellular channels), have been identified over the last few years. A striking feature of the CLIC family of ion channels is that they can exist in a water- soluble state as well as a membrane-bound state. A major step forward in understanding the functioning of these channels has been the recent crystal structure determination of one family member, CLIC1. The structure confirms that CLICs are members of the glutathione S- transferase superfamily and provides clues as to how CLICs can insert into membranes to form chloride channels. (69 refs).

  15. Glutathione transferases: emerging multidisciplinary tools in red and green biotechnology.

    Science.gov (United States)

    Chronopoulou, Evangelia G; Labrou, Nikolaos E

    2009-01-01

    Cytosolic glutathione transferases (GSTs) are a diverse family of enzymes involved in a wide range of biological processes, many of which involve the conjugation of the tripeptide glutathione (GSH) to an electrophilic substrate. Detailed studies of GSTs are justified because of the considerable interest of these enzymes in medicine, agriculture and analytical biotechnology. For example, in medicine, GSTs are explored as molecular targets for the design of new anticancer drugs as a plausible means to sensitize drug-resistant tumors that overexpress GSTs. In agriculture, GSTs are exploited in the development of transgenic plants with increased resistance to biotic and abiotic stresses. Recently, selected isoenzymes of GSTs have found successful applications in the development of enzyme biosensors for the direct monitoring of environmental pollutants, such as herbicides and insecticides. This review article summarizes recent representative patents related to GSTs and their applications in biotechnology.

  16. Inhibition of human glutathione transferases by dinitronaphthalene derivatives.

    Science.gov (United States)

    Groom, Hilary; Lee, Moses; Patil, Pravin; Josephy, P David

    2014-08-01

    Glutathione transferase (GST) enzymes catalyze the conjugation of glutathione with reactive functional groups of endogenous compounds and xenobiotics, including halonitroaromatics. 1-Chloro-2,4-dinitrobenzene (CDNB) is one of the most commonly used substrates for GST activity assays. We have studied the interactions of dinitronaphthalene analogues of CDNB with recombinant human GST enzymes (Alpha, Mu, and Pi classes) expressed in Escherichia coli. Dinitronaphthalene derivatives were found to be GST inhibitors. The highest potency of inhibition was observed towards Mu-class GSTs, M1-1 and M2-2; IC50 values for 1-methoxy- and 1-ethoxy-2,4-dinitronaphthalene were in the high nanomolar to low micromolar range. Inhibition accompanies the formation, at the enzyme active site, of very stable Meisenheimer complex intermediates.

  17. Energy consumption: energy consumption in mainland Norway

    Energy Technology Data Exchange (ETDEWEB)

    Magnussen, Inger Helene; Killingland, Magnus; Spilde, Dag

    2012-07-25

    The purpose of this report is to describe trends in energy consumption in mainland Norway, with an emphasis on key trends within the largest consumer groups. We also explain common terms and concepts in the field of energy consumption. Finally, we look at forecasts for future energy consumption, produced by bodies outside NVE. Total final energy consumption in mainland Norway in 2009 was 207 TWh. The most important end-user groups are households, service industries, manufacturing industry and transport. In addition, the energy sector in mainland Norway consumed 15 TWh. Energy consumed in the energy sector is not considered as final consumption, as the energy is used to produce new energy products. The long-term trend in energy consumption in mainland Norway is that fuel in the transport sector and electricity for the energy sector increases, while energy consumption in other sectors flattens out. The main reason for an increased use of fuel in the transport sector is the rise in the number of motorised machinery and vehicles in mainland Norway. This has caused a rise in gasoline and diesel consumption of 75 per cent since 1976. The petroleum sector is the largest consumer of energy within the energy sector in mainland Norway, and electricity from onshore to platforms in the North Sea and to new shore side installations has led to a rise in electricity consumption from 1 TWh in 1995 to 5 TWh in 2009. The energy consumption in households showed flat trend from 1996 to 2009, after many years of growth. The main reasons are a warmer climate, higher energy prices, the use of heats pumps and more energy-efficient buildings. In the service industries, the growth in energy consumptions has slightly decreased since the late 1990s, for much the same reasons as for households. In manufacturing industries the energy consumption have flatten out mainly due to the closure of energy-intensive businesses and the establishment of new more energy-efficient businesses. Electricity is

  18. Consumption Habits and Humps

    DEFF Research Database (Denmark)

    Kraft, Holger; Munk, Claus; Seifried, Frank Thomas

    We show that the optimal consumption of an individual over the life cycle can have the hump shape (inverted U-shape) observed empirically if the preferences of the individual exhibit internal habit formation. In the absence of habit formation, an impatient individual would prefer a decreasing...... consumption path over life. However, because of habit formation, a high initial consumption would lead to high required consumption in the future. To cover the future required consumption, wealth is set aside, but the necessary amount decreases with age which allows consumption to increase in the early part...... of life. At some age, the impatience outweighs the habit concerns so that consumption starts to decrease. We derive the optimal consumption strategy in closed form, deduce sufficient conditions for the presence of a consumption hump, and characterize the age at which the hump occurs. Numerical examples...

  19. Consumption Habits and Humps

    DEFF Research Database (Denmark)

    Kraft, Holger; Munk, Claus; Seifried, Frank Thomas

    2017-01-01

    We show that the optimal consumption of an individual over the life cycle can have the hump shape (inverted U-shape) observed empirically if the preferences of the individual exhibit internal habit formation. In the absence of habit formation, an impatient individual would prefer a decreasing...... consumption path over life. However, because of habit formation, a high initial consumption would lead to high required consumption in the future. To cover the future required consumption, wealth is set aside, but the necessary amount decreases with age which allows consumption to increase in the early part...... of life. At some age, the impatience outweighs the habit concerns so that consumption starts to decrease. We derive the optimal consumption strategy in closed form, deduce sufficient conditions for the presence of a consumption hump, and characterize the age at which the hump occurs. Numerical examples...

  20. Purification and characterization of the commercialized, cloned Bacillus megaterium. alpha. -amylase. Pt. 2. Transferase properties

    Energy Technology Data Exchange (ETDEWEB)

    Brumm, P.J.; Hebeda, R.E.; Teague, W.M.

    1991-08-01

    Using an assay procedure based on reduction of iodine binding to starch, Bacillus megaterium, {alpha}-amylase (BMA) demonstrated transferase activity using a wide range of acceptors. The enzyme had an absolute requirement for glucose or glucosides for acceptor molecules. Maltose acted as a transferase acceptor at low concentrations and as an inhibitor of starch hydrolysis at high concentrations. Kinetic analysis indicated that, in the presence of a suitable acceptor, the mechanism of starch hydrolysis is Ping Pong Bi Bi. The products of the transferase reaction have been determined using p-nitro-{alpha}-D-glucopyranoside as acceptor combined with a novel HPLC-based system for product detection. (orig.).

  1. Glutathione Transferase GSTπ In Breast Tumors Evaluated By Three Techniques

    Directory of Open Access Journals (Sweden)

    Rafael Molina

    1993-01-01

    Full Text Available The glutathione transferases are involved in intracellular detoxification reactions. One of these, GSTπ, is elevated in some breast cancer cells, particularly cells selected for resistance to anticancer agents. We evaluated GSTπ expression in 60 human breast tumors by three techniques, immunohistochemistry, Northern hybridization, and Western blot analysis. There was a significant positive correlation between the three methods, with complete concordance seen in 64% of the tumors. There was strong, inverse relationship between GSTπ expression and steroid receptor status with all of the techniques utili zed. [n addition, there was a trend toward higher GSTπ expression in poorly differentiated tumors, but no correlation was found between tumor GSTπ content and DNA ploidy or %S-phase. GSTπ expression was also detected in adjacent benign breast tissue as well as infiltrating lymphocytes; this expression may contribute to GSTπ measurements using either Northern hybridization or Western blot analysis. These re sults suggest that immunohistochemistry is the method of choice for measuring GSTπ in breast tumors.

  2. Benzene oxide is a substrate for glutathione S-transferases.

    Science.gov (United States)

    Zarth, Adam T; Murphy, Sharon E; Hecht, Stephen S

    2015-12-01

    Benzene is a known human carcinogen which must be activated to benzene oxide (BO) to exert its carcinogenic potential. BO can be detoxified in vivo by reaction with glutathione and excretion in the urine as S-phenylmercapturic acid. This process may be catalyzed by glutathione S-transferases (GSTs), but kinetic data for this reaction have not been published. Therefore, we incubated GSTA1, GSTT1, GSTM1, and GSTP1 with glutathione and BO and quantified the formation of S-phenylglutathione. Kinetic parameters were determined for GSTT1 and GSTP1. At 37 °C, the putative Km and Vmax values for GSTT1 were 420 μM and 450 fmol/s, respectively, while those for GSTP1 were 3600 μM and 3100 fmol/s. GSTA1 and GSTM1 did not exhibit sufficient activity for determination of kinetic parameters. We conclude that GSTT1 is a critical enzyme in the detoxification of BO and that GSTP1 may also play an important role, while GSTA1 and GSTM1 seem to be less important.

  3. New substrates and activity of Phanerochaete chrysosporium Omega glutathione transferases.

    Science.gov (United States)

    Meux, Edgar; Morel, Mélanie; Lamant, Tiphaine; Gérardin, Philippe; Jacquot, Jean-Pierre; Dumarçay, Stéphane; Gelhaye, Eric

    2013-02-01

    Omega glutathione transferases (GSTO) constitute a family of proteins with variable distribution throughout living organisms. It is notably expanded in several fungi and particularly in the wood-degrading fungus Phanerochaete chrysosporium, raising questions concerning the function(s) and potential redundancy of these enzymes. Within the fungal families, GSTOs have been poorly studied and their functions remain rather sketchy. In this study, we have used fluorescent compounds as activity reporters to identify putative ligands. Experiments using 5-chloromethylfluorescein diacetate as a tool combined with mass analyses showed that GSTOs are able to cleave ester bonds. Using this property, we developed a specific activity-based profiling method for identifying ligands of PcGSTO3 and PcGSTO4. The results suggest that GSTOs could be involved in the catabolism of toxic compounds like tetralone derivatives. Biochemical investigations demonstrated that these enzymes are able to catalyze deglutathionylation reactions thanks to the presence of a catalytic cysteine residue. To access the physiological function of these enzymes and notably during the wood interaction, recombinant proteins have been immobilized on CNBr Sepharose and challenged with beech wood extracts. Coupled with GC-MS experiments this ligand fishing method allowed to identify terpenes as potential substrates of Omega GST suggesting a physiological role during the wood-fungus interactions.

  4. Inactivation of Anopheles gambiae Glutathione Transferase ε2 by Epiphyllocoumarin

    Directory of Open Access Journals (Sweden)

    Patience Marimo

    2016-01-01

    Full Text Available Glutathione transferases (GSTs are part of a major family of detoxifying enzymes that can catalyze the reductive dehydrochlorination of dichlorodiphenyltrichloroethane (DDT. The delta and epsilon classes of insect GSTs have been implicated in conferring resistance to this insecticide. In this study, the inactivation of Anopheles gambiae GSTε2 by epiphyllocoumarin (Tral 1 was investigated. Recombinant AgGSTε2 was expressed in Escherichia coli cells containing a pET3a-AGSTε2 plasmid and purified by affinity chromatography. Tral 1 was shown to inactivate GSTε2 both in a time-dependent manner and in a concentration-dependent manner. The half-life of GSTε2 in the presence of 25 μM ethacrynic acid (ETA was 22 minutes and with Tral 1 was 30 minutes, indicating that Tral 1 was not as efficient as ETA as an inactivator. The inactivation parameters kinact and KI were found to be 0.020 ± 0.001 min−1 and 7.5 ± 2.1 μM, respectively, after 90 minutes of incubation. Inactivation of GSTε2 by Tral 1 implies that Tral 1 covalently binds to this enzyme in vitro and would be expected to exhibit time-dependent effects on the enzyme in vivo. Tral 1, therefore, would produce irreversible effects when used together with dichlorodiphenyltrichloroethane (DDT in malaria control programmes where resistance is mediated by GSTs.

  5. Glutathione S-transferase, incense burning and asthma in children.

    Science.gov (United States)

    Wang, I-J; Tsai, C-H; Chen, C-H; Tung, K-Y; Lee, Y L

    2011-06-01

    Incense burning is a popular practice in many family homes and temples. However, little is known about the effects of indoor incense burning and genetic polymorphisms on asthma. This study evaluated the effects of indoor incense burning and glutathione S-transferase (GST) genetic polymorphisms on asthma and wheeze. In 2007, 3,764 seventh-grade schoolchildren (mean±sd age 12.42±0.65 yrs) were evaluated using a standard questionnaire for information about respiratory symptoms and environmental exposures. Multiple logistic regressions were performed to assess the association between GST polymorphisms and incense burning frequency on asthma and wheeze, after adjusting for potential confounders. The frequency of incense burning at home was associated with increased risk of current asthma (p=0.05), medication use (p=0.03) and exercise wheeze (p=0.001). GST1 (GSTT1) null genotypes were associated with current asthma (OR 1.43, 95% CI 1.00-2.04) and medication use (OR 1.46, 95% CI 1.01-2.22). GSTT1 showed a significant interactive effect with incense burning on current asthma, current wheeze and nocturnal wheeze. The frequency of incense burning was associated with increased risk of current asthma, medication use, lifetime wheeze, nocturnal wheeze and exercise wheeze in an exposure-response manner among children with GSTT1 null genotype (pIncense burning is a risk factor for asthma and wheezing, especially in GSTT1 genetically susceptible children.

  6. The role of glutathione transferases in renal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Ćorić Vesna

    2016-01-01

    Full Text Available Mounting evidence suggest that members of the subfamily of cytosolic glutathione S-transferases (GSTs possess roles far beyond the classical glutathione-dependent enzymatic conjugation of electrophilic metabolites and xenobiotics. Namely, monomeric forms of certain GSTs are capable of forming protein: protein interactions with protein kinases and regulate cell apoptotic pathways. Due to this dual functionality of cytosolic GSTs, they might be implicated in both the development and the progression of renal cell carcinoma (RCC. Prominent genetic heterogeneity, resulting from the gene deletions, as well as from SNPs in the coding and non-coding regions of GST genes, might affect GST isoenzyme profiles in renal parenchyma and therefore serve as a valuable indicator for predicting the risk of cancer development. Namely, GSTs are involved in the biotransformation of several compounds recognized as risk factors for RCC. The most potent carcinogen of polycyclic aromatic hydrocarbon diol epoxides, present in cigarette smoke, is of benzo(apyrene (BPDE, detoxified by GSTs. So far, the relationship between GST genotype and BPDE-DNA adduct formation, in determining the risk for RCC, has not been evaluated in patients with RCC. Although the association between certain individual and combined GST genotypes and RCC risk has been debated in a the literature, the data on the prognostic value of GST polymorphism in patients with RCC are scarce, probably due to the fact that the molecular mechanism supporting the role of GSTs in RCC progression has not been clarified as yet.

  7. MDI Consumption Up

    Institute of Scientific and Technical Information of China (English)

    Li Zhaobao

    2007-01-01

    @@ The consumption of MDI (diphenylmethane diisocyanate) in China was 631 thousand tons in 2006, an increase of 36.6% over 2005. The consumption of pure MDI was 231 thousand tons, an increase of 38.3% and the consumption of polymerized MDI was 400 thousand tons, an increase of 35.6%.

  8. Serum fucosyl transferase activity and serum fucose levels as diagnostic tools in malignancy.

    Directory of Open Access Journals (Sweden)

    Sen,Umi

    1983-12-01

    Full Text Available Glycoproteins play a significant role in neoplastic transformations. Both the levels of fucose and the activity of fucosyl transferase, which mediates the assembly of the oligosaccharide moieties of the glycoprotein chains, have been found to be elevated in neoplastic conditions. Since these elevations are common features of a variety of neoplastic cells, these two have been designated as non-specific markers of malignancy. In the present study, the fucose level and fucosyl transferase activity were determined in the sera of cancer patients and an attempt was made to establish a relationship between the two. It was found that both the fucose levels and fucosyl transferase activities showed considerable elevation in the five cancer groups studied, establishing them as useful diagnostic parameters. However, it was also observed that the rate of increased fucosyl transferase activity was not fully reflected in the resulting serum fucose levels in a few cases.

  9. 21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

    Science.gov (United States)

    2010-04-01

    ... serum and plasma. Alanine amino transferase measurements are used in the diagnosis and treatment of certain liver diseases (e.g., viral hepatitis and cirrhosis) and heart diseases. (b) Classification. Class...

  10. Acetate:succinate CoA-transferase in the hydrogenosomes of Trichomonas vaginalis: Identification and characterization

    NARCIS (Netherlands)

    K.W.A. Grinsven; S. Rosnowsky (Silke); S.W.H. van Weelden (Susanne); S. Pütz (Simone); M. van der Giezen (Mark); W. Martin (William); J.J. van Hellemond (Jaap); A.G.M. Tielens (Aloysius); K. Henze (Katrin)

    2008-01-01

    textabstractAcetate:succinate CoA-transferases (ASCT) are acetate-producing enzymes in hydrogenosomes, anaerobically functioning mitochondria and in the aerobically functioning mitochondria of trypanosomatids. Although acetate is produced in the hydrogenosomes of a number of anaerobic microbial

  11. Glutathione transferase classes alpha, pi, and mu: GSH activation mechanism.

    Science.gov (United States)

    Dourado, Daniel F A R; Fernandes, Pedro Alexandrino; Ramos, Maria João

    2010-10-14

    Since the early 1960s, glutathione transferases (GSTs) have been described as detoxification enzymes. In fact, GSTs are the most important enzymes involved in the metabolism of electrophilic xenobiotic/endobiotic compounds. These enzymes are able to catalyze the nucleophilic addition of glutathione (GSH) sulfur thiolate to a wide range of electrophilic substrates, building up a less toxic and more soluble compound. Cytosolic classes alpha, pi, and mu are the most extensively studied GSTs. However, many of the catalytic events are still poorly understood. In the present work, we have resorted to density functional theory (DFT) and to potential of mean force (PMF) calculations to determine the GSH activation mechanism of GSTP1-1 and GSTM1-1 isoenzymes. For the GSTP1-1 enzyme, we have demonstrated that a water molecule, after an initial conformational rearrangement of GSH, can assist a proton transfer between the GSH cysteine thiol (GSH-SH) and the GSH glutamate alpha carboxylate (GSH-COO(-)) groups. The energy barrier associated with the proton transfer is 11.36 kcal·mol(-1). The GSTM1-1 enzyme shows a completely different behavior from the previous isoenzyme. In this case, two water molecules, positioned between the GSH-SH and the ξ N atom of His107, working like a bridge, are able to promote the proton transfer between these two active groups with an energy barrier of 7.98 kcal·mol(-1). All our results are consistent with all the enzymes kinetics and mutagenesis experimental studies.

  12. Analysis of Arabidopsis glutathione-transferases in yeast.

    Science.gov (United States)

    Krajewski, Matthias P; Kanawati, Basem; Fekete, Agnes; Kowalski, Natalie; Schmitt-Kopplin, Philippe; Grill, Erwin

    2013-07-01

    The genome of Arabidopsis thaliana encodes 54 functional glutathione transferases (GSTs), classified in seven clades. Although plant GSTs have been implicated in the detoxification of xenobiotics, such as herbicides, extensive redundancy within this large gene family impedes a functional analysis in planta. In this study, a GST-deficient yeast strain was established as a system for analyzing plant GSTs that allows screening for GST substrates and identifying substrate preferences within the plant GST family. To this end, five yeast genes encoding GSTs and GST-related proteins were simultaneously disrupted. The resulting yeast quintuple mutant showed a strongly reduced conjugation of the GST substrates 1-chloro-2,4-dinitrobenzene (CDNB) and 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl). Consistently, the quintuple mutant was hypersensitive to CDNB, and this phenotype was complemented by the inducible expression of Arabidopsis GSTs. The conjugating activity of the plant GSTs was assessed by in vitro enzymatic assays and via analysis of exposed yeast cells. The formation of glutathione adducts with dinitrobenzene was unequivocally verified by stable isotope labeling and subsequent accurate ultrahigh-resolution mass spectrometry (ICR-FTMS). Analysis of Arabidopsis GSTs encompassing six clades and 42 members demonstrated functional expression in yeast by using CDNB and NBD-Cl as model substrates. Subsequently, the established yeast system was explored for its potential to screen the Arabidopsis GST family for conjugation of the fungicide anilazine. Thirty Arabidopsis GSTs were identified that conferred increased levels of glutathionylated anilazine. Efficient anilazine conjugation was observed in the presence of the phi, tau, and theta clade GSTs including AtGSTF2, AtGSTF4, AtGSTF6, AtGSTF8, AtGSTF10, and AtGSTT2, none of which had previously been known to contribute to fungicide detoxification. ICR-FTMS analysis of yeast extracts allowed the simultaneous detection and

  13. Roles for glutathione transferases in plant secondary metabolism.

    Science.gov (United States)

    Dixon, David P; Skipsey, Mark; Edwards, Robert

    2010-03-01

    Plant glutathione transferases (GSTs) are classified as enzymes of secondary metabolism, but while their roles in catalysing the conjugation and detoxification of herbicides are well known, their endogenous functions are largely obscure. Thus, while the presence of GST-derived S-glutathionylated xenobiotics have been described in many plants, there is little direct evidence for the accumulation of similarly conjugated natural products, despite the presence of a complex and dichotomous metabolic pathway which processes these reaction products. The conservation in glutathione conjugating and processing pathways, the co-regulation of GSTs with inducible plant secondary metabolism and biochemical studies showing the potential of these enzymes to conjugate reactive natural products are all suggestive of important endogenous functions. As a framework for addressing these enigmatic functions we postulate that either: (a) the natural reaction products of GSTs are unstable and undergo reversible S-glutathionylation; (b) the conjugation products of GSTs are very rapidly processed to derived metabolites; (c) GSTs do not catalyse conventional conjugation reactions but instead use glutathione as a cofactor rather than co-substrate; or (d) GSTs are non-catalytic and function as transporter proteins for secondary metabolites and their unstable intermediates. In this review, we describe how enzyme biochemistry and informatics are providing clues as to GST function allowing for the critical evaluation of each of these hypotheses. We also present evidence for the involvement of GSTs in the synthesis of sulfur-containing secondary metabolites such as volatiles and glucosinolates, and the conjugation, transport and storage of reactive oxylipins, phenolics and flavonoids.

  14. Multiple roles for plant glutathione transferases in xenobiotic detoxification.

    Science.gov (United States)

    Cummins, Ian; Dixon, David P; Freitag-Pohl, Stefanie; Skipsey, Mark; Edwards, Robert

    2011-05-01

    Discovered 40 years ago, plant glutathione transferases (GSTs) now have a well-established role in determining herbicide metabolism and selectivity in crops and weeds. Within the GST superfamily, the numerous and plant-specific phi (F) and tau (U) classes are largely responsible for catalyzing glutathione-dependent reactions with xenobiotics, notably conjugation leading to detoxification and, more rarely, bioactivating isomerizations. In total, the crystal structures of 10 plant GSTs have been solved and a highly conserved N-terminal glutathione binding domain and structurally diverse C-terminal hydrophobic domain identified, along with key coordinating residues. Unlike drug-detoxifying mammalian GSTs, plant enzymes utlilize a catalytic serine in place of a tyrosine residue. Both GSTFs and GSTUs undergo changes in structure during catalysis indicative of an induced fit mechanism on substrate binding, with an understanding of plant GST structure/function allowing these proteins to be engineered for novel functions in detoxification and ligand recognition. Several major crops produce alternative thiols, with GSTUs shown to use homoglutathione in preference to glutathione, in herbicide detoxification reactions in soybeans. Similarly, hydroxymethylglutathione is used, in addition to glutathione in detoxifying the herbicide fenoxaprop in wheat. Following GST action, plants are able to rapidly process glutathione conjugates by at least two distinct pathways, with the available evidence suggesting these function in an organ- and species-specific manner. Roles for GSTs in endogenous metabolism are less well defined, with the enzymes linked to a diverse range of functions, including signaling, counteracting oxidative stress, and detoxifying and transporting secondary metabolites.

  15. Regulation of the cardiac muscle ryanodine receptor by glutathione transferases.

    Science.gov (United States)

    Dulhunty, Angela F; Hewawasam, Ruwani; Liu, Dan; Casarotto, Marco G; Board, Philip G

    2011-05-01

    Glutathione transferases (GSTs) are generally recognized for their role in phase II detoxification reactions. However, it is becoming increasingly apparent that members of the GST family also have a diverse range of other functions that are, in general, unrelated to detoxification. One such action is a specific inhibition of the cardiac isoform of the ryanodine receptor (RyR2) intracellular Ca(2+) release channel. In this review, we compare functional and physical interactions between members of the GST family, including GSTO1-1, GSTA1-1, and GSTM2-2, with RyR2 and with the skeletal isoform of the ryanodine receptor (RyR1). The active part of the muscle-specific GSTM2-2 is localized to its nonenzymatic C-terminal α-helical bundle, centered around α-helix 6. The GSTM2-2 binding site is in divergent region 3 (DR3 region) of RyR2. The sequence differences between the DR3 regions of RyR1 and RyR2 explain the specificity of the GSTs for one isoform of the protein. GSTM2-2 is one of the few known endogenous inhibitors of the cardiac RyR and is likely to be important in maintaining low RyR2 activity during diastole. We discuss interactions between a nonenzymatic member of the GST structural family, the CLIC-2 (type 2 chloride intracellular channel) protein, which inhibits both RyR1 and RyR2. The possibility that the GST and CLIC2 proteins bind to different sites on the RyR, and that different structures within the GST and CLIC proteins bind to RyR channels, is discussed. We conclude that the C-terminal part of GSTM2-2 may provide the basis of a therapeutic compound for use in cardiac disorders.

  16. Role of glutathione transferases in the mechanism of brostallicin activation.

    Science.gov (United States)

    Pezzola, Silvia; Antonini, Giovanni; Geroni, Cristina; Beria, Italo; Colombo, Maristella; Broggini, Massimo; Marchini, Sergio; Mongelli, Nicola; Leboffe, Loris; MacArthur, Robert; Mozzi, Alessia Francesca; Federici, Giorgio; Caccuri, Anna Maria

    2010-01-12

    Brostallicin is a novel and unique glutathione transferase-activated pro-drug with promising anticancer activity, currently in phase I and II clinical evaluation. In this work, we show that, in comparison with the parental cell line showing low GST levels, the cytotoxic activity of brostallicin is significantly enhanced in the human breast carcinoma MCF-7 cell line, transfected with either human GST-pi or GST-mu. Moreover, we describe in detail the interaction of brostallicin with GSH in the presence of GSTP1-1 and GSTM2-2, the predominant GST isoenzymes found within tumor cells. The experiments reported here indicate that brostallicin binds reversibly to both isoenzymes with K(d) values in the micromolar range (the affinity being higher for GSTM2-2). Direct evidence that both GSTP1-1 and GSTM2-2 isoenzymes catalyze the Michael addition reaction of GSH to brostallicin has been obtained both by an HPLC-MS technique and by a new fluorometric assay. We also saw the rapid formation of an intermediate reactive species, which is slowly converted into the final products. This intermediate, identified as the alpha-chloroamido derivative of the GSH-brostallicin adduct, is able to alkylate DNA in a sequence-specific manner and appears to be the active form of the drug. The kinetic behavior of the reaction between brostallicin and GSH, catalyzed by GSTP1-1, has been studied in detail, and a minimum kinetic scheme that suitably describes the experimental data is provided. Overall, these data fully support and extend the findings that brostallicin could be indicated for the treatment of tumor overexpressing the pi or mu class GST.

  17. Prediction of substrates for glutathione transferases by covalent docking.

    Science.gov (United States)

    Dong, Guang Qiang; Calhoun, Sara; Fan, Hao; Kalyanaraman, Chakrapani; Branch, Megan C; Mashiyama, Susan T; London, Nir; Jacobson, Matthew P; Babbitt, Patricia C; Shoichet, Brian K; Armstrong, Richard N; Sali, Andrej

    2014-06-23

    Enzymes in the glutathione transferase (GST) superfamily catalyze the conjugation of glutathione (GSH) to electrophilic substrates. As a consequence they are involved in a number of key biological processes, including protection of cells against chemical damage, steroid and prostaglandin biosynthesis, tyrosine catabolism, and cell apoptosis. Although virtual screening has been used widely to discover substrates by docking potential noncovalent ligands into active site clefts of enzymes, docking has been rarely constrained by a covalent bond between the enzyme and ligand. In this study, we investigate the accuracy of docking poses and substrate discovery in the GST superfamily, by docking 6738 potential ligands from the KEGG and MetaCyc compound libraries into 14 representative GST enzymes with known structures and substrates using the PLOP program [ Jacobson Proteins 2004 , 55 , 351 ]. For X-ray structures as receptors, one of the top 3 ranked models is within 3 Å all-atom root mean square deviation (RMSD) of the native complex in 11 of the 14 cases; the enrichment LogAUC value is better than random in all cases, and better than 25 in 7 of 11 cases. For comparative models as receptors, near-native ligand-enzyme configurations are often sampled but difficult to rank highly. For models based on templates with the highest sequence identity, the enrichment LogAUC is better than 25 in 5 of 11 cases, not significantly different from the crystal structures. In conclusion, we show that covalent docking can be a useful tool for substrate discovery and point out specific challenges for future method improvement.

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

    Science.gov (United States)

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

    2015-01-01

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

  19. Alteration of glutathione S-transferase properties during the development of Micromelalopha troglodyta larvae (Lepidoptera: Notodontidae)

    Institute of Scientific and Technical Information of China (English)

    TANG Fang; ZHANG Xiu-bo; LIU Yu-sheng; GAO Xi-wu

    2011-01-01

    Micromelalopha troglodyta (Graeser) is an important pest ofpoplar in China. Glutathione S-transferases (GSTs) are known to beresponsible for adaptation mechanisms of M. Troglodyta. The activitiesand kinetic constants of glutathione S-transferases in M. Troglodyta werestudied. Significant differences in glutathione S-transferase activity andkinetic characteristics were observed among five instars of M. Troglodytalarvae. Furthermore, the inhibition of glutathione S-transferase activity infive instars by 24 inhibitors was conducted. The results show the inhibi-tion of GST activity of different instars by 24 inhibitors was different.For GST activity in the 1st instar chlorpyrifos, lambda-cyhalothrin,endosulfan, abamectin, fipronil and pyridaben were the best inhibitorstested, and for GST activity in the 2nd instar, tannic acid and quercetinwere the most potent inhibitors tested, and for GST activity in the 3rdinstar, the inhibitory effects of quercetin, chlorpyrifos andlambda-cyhalothrin were the highest, and for GST activity in the 4thinstar, quercetin and lambda-cyhalothrin were the best inhibitors, and theinhibitory effect of pboxim was the highest for GST activity in the 5thinstar. Our results show that glutathione S-transferases in different iustarsare qualitatively different in isozyme composition and thus different insensitivity to inhibitors.

  20. Cracking the Consumption Nut

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Increasing domestic consumption has become a hot topic filtering through various economic circles in China. In the aftermath of the global financial crisis, the call has gone out to emphasize consumption and downplay saving among people in the international community. Xia Bin,

  1. Experience and Sustainable Consumption

    DEFF Research Database (Denmark)

    Rasmussen, Tove Arendt

    consumption may re-enchant ordinary consumption and thereby even become a part of marketing and the experience economy. New layers of meaning are at stake and altruistic motives come into play; doing something good for someone or something, aside from oneself, is a very strong trigger of positive emotions......Experience understood as experience-based consumption is by now fairly absent from the research agenda of the different theories on sustainable consumption. On the basis of Colin Campbell’s notion of romantic ethics and emotional sentimentality in modern hedonism, I claim that sustainable....... Very often, however, the actual purchase does not live up to the demands of doing good in the sustainable consumption chain, and the individual might end up with a guilty conscience, which again is a possible trigger for lingering in a sentimental mode of guilt. Emotions of sentimentality may actually...

  2. Experience and Sustainable Consumption

    DEFF Research Database (Denmark)

    Rasmussen, Tove Arendt

    2014-01-01

    consumption may re-enchant ordinary consumption and thereby even become a part of marketing and the experience economy. New layers of meaning are at stake and altruistic motives come into play; doing something good for someone or something, aside from oneself, is a very strong trigger of positive emotions......Experience understood as experience-based consumption is by now fairly absent from the research agenda of the different theories on sustainable consumption. On the basis of Colin Campbell’s notion of romantic ethics and emotional sentimentality in modern hedonism, I claim that sustainable....... Very often, however, the actual purchase does not live up to the demands of doing good in the sustainable consumption chain, and the individual might end up with a guilty conscience, which again is a possible trigger for lingering in a sentimental mode of guilt. Emotions of sentimentality may actually...

  3. ADH1B and ADH1C Genotype, Alcohol Consumption and Biomarkers of Liver Function

    DEFF Research Database (Denmark)

    Lawlor, Debbie A; Benn, Marianne; Zuccolo, Luisa;

    2014-01-01

    1C genes as instrumental variables (IV) to estimate the causal effect of long-term alcohol consumption on alanine aminotransferase (ALT), γ-glutamyl-transferase (γ-GT), alkaline phosphatase (ALP), bilirubin and prothrombin action. Analyses were undertaken on 58,313 Danes (mean age 56). RESULTS......BACKGROUND: The effect of alcohol consumption on liver function is difficult to determine because of reporting bias and potential residual confounding. Our aim was to determine this effect using genetic variants to proxy for the unbiased effect of alcohol. METHODS: We used variants in ADH1B and ADH......: In both confounder adjusted multivariable and genetic-IV analyses greater alcohol consumption, amongst those who drank any alcohol, was associated with higher ALT [mean difference per doubling of alcohol consumption: 3.4% (95% CI: 3.1, 3.7) from multivariable analyses and 3.7% (-4.5, 11.9) from genetic...

  4. Effect of pH on the Hydrolytic Kinetics of Gamma-Glutamyl Transferase from Bacillus subtilis

    Directory of Open Access Journals (Sweden)

    Sharath Balakrishna

    2014-01-01

    Full Text Available The effect of pH on the steady state kinetics of gamma-glutamyl transferase (GGT from Bacillus subtilis was examined using glutamyl-(3-carboxyl-4-nitroanilide as the chromogenic reporter substrate. The enzyme was active in the pH range 7.0–11.0 with the optimum activity at pH 11.0. We noticed a pH dependent transformation in the nature of substrate consumption kinetics. The substrate saturation curves were hyperbolic in the pH range 7.0–9.0 but changed into sigmoid form at pH 10.0 and 11.0. Hill’s coefficients were >1. We also analysed the effect of pH on the structure of the enzyme. The circular dichroism spectra of the enzyme sample at pH 9.0 and 11.0 were coincidental in both far and near UV regions indicating conservation of the secondary and tertiary structures, respectively. The molecular weight of the enzyme sample was the same in both pH 7.0 and 11.0 indicating conservation of the quaternary structure. These results show that the kinetic transformation does not involve significant conformational changes. Cooperative binding of multiple substrate molecules may not be the basis for the sigmoid kinetics as only one substrate binding site has been noticed in the reported crystal structures of B. subtilis GGT.

  5. Nuclear translocation of glutathione transferase omega is a progression marker in Barrett's esophagus

    DEFF Research Database (Denmark)

    Piaggi, Simona; Marchi, Santino; Ciancia, Eugenio

    2009-01-01

    Barrett's esophagus (BE) represents a major risk factor for esophageal adenocarcinoma (AC). For this reason, patients with BE are subjected to a systematic endoscopic surveillance to detect initial evolution towards non-invasive neoplasia (NiN) and cancer, that eventually occurs only in a small f...... fraction of BE patients. This study was aimed to investigate the possible role of glutathione-S-transferase-omega 1 (GSTO1), a recently discovered member of the glutathione-S-transferase family, as a progression marker in the Barrett's disease in order to improve the diagnosis of Ni...... equally divided between nuclear, cytoplasmic and diffuse staining (2 each, respectively). Experiments in vitro showed that in human HeLa cancer cells, GSTO1 translocates into the nucleus as a consequence of heath shock. These findings suggested that the nuclear translocation of glutathione-S-transferase-omega...

  6. Glutathione transferases and development of new principles to overcome drug resistance.

    Science.gov (United States)

    Sau, Andrea; Pellizzari Tregno, Francesca; Valentino, Francesco; Federici, Giorgio; Caccuri, Anna Maria

    2010-08-15

    Chemoresistance is a multifactorial phenomenon and many studies clearly show that a coordinated expression of efflux transporter proteins and phase II conjugating enzymes in tumor cells is linked to the development of the multidrug resistance phenotype. In particular, the overexpression of glutathione S-transferases and efflux pumps in tumors may reduce the reactivity of various anticancer drugs. In recent years it has become evident that glutathione S-transferases are also involved in the control of apoptosis through the inhibition of the JNK signaling pathway. As such, the glutathione S-transferase superfamily has become the focus of extensive pharmaceutical research in attempt to generate more efficient anticancer agents. Here we present an overview of the GST inhibitors and the GST-activated pro-drugs utilized to date to overcome drug resistance.

  7. The role of N-acetyl-cysteine in the lung remote injury after hepatic ischemia and reperfusion in rabbits O papel da N-acetil-cisteína nas lesões pulmonares provocadas à distância pela isquemia e reperfusão hepática em coelhos

    Directory of Open Access Journals (Sweden)

    Angela Potter de Castro

    2012-01-01

    Full Text Available PURPOSE: To study the lesions in the lung of rabbits caused by ischemia/reperfusion hepatic (I/R after the use of N-acetyl-cysteine (NAC. METHODS: Twenty-four rabbits distributed in two groups: control group GI (n = 12 5% glucose solution and experiment group GII (n = 12 NAC. The animals were pre-anesthetized with 1% acepromazine maleate and anesthetized with ketamine 10% and 2% xylazine intramuscularly. The GI and GII were given glucose solution intravenously or NAC 15min before occlusion of the hepatic pedicle (30 min. After the period of reperfusion of 24h (n = 6 or 48h (n = 6, liver and lung samples were collected for histology and immunohistochemistry to assess the impairment of cell. RESULTS: The animals of GII and GII-24h-48h showed parenchyma liver close to normal, when using NAC. The GII and GII-24h-48h showed lower thickness of alveolar cells that GI and GI-24h-48h. The expression of caspase 3 in lung cells GII presented smaller value compared to the GI group. CONCLUSION: N-acetyl-cysteine administered 15min prior to the injury ischemia/reperfusion had a significant protective role by minimizing lung injury and apoptotic morphology in the period observed.OBJETIVO: Estudar as lesões no fígado e no pulmão de coelhos, provocadas pela isquemia/reperfusão hepática (I/R moduladas pelo uso da N-acetil-cisteína (NAC. MÉTODOS: Vinte e quatro coelhos distribuídos em dois grupos: Grupo controle GI (n=12 solução de glicose 5% e Grupo experimento GII (n=12 NAC. Os animais foram pré-anestesiados com maleato de acepromazina 1% e anestesiados com cloridrato de quetamina 10% e xilazina 2% via intramuscular. Os grupos GI e GII receberam solução glicosada ou NAC respectivamente via endovenosa 15min antes da oclusão do pedículo hepático (30 min. Após iniciou-se o período de reperfusão por 24h (n=6 ou 48h (n=6, terminada a reperfusão, amostras do fígado e pulmão foram coletadas para a histologia e imunoistoquímica para avaliar o

  8. Value of urine NGAL and N - acetyl - β - D - glucosaminidase in early diagnosis of IgA nephropathy%尿NGAL和N-乙酰-β-D-氨基葡萄糖苷酶对IgA肾病早期诊断的价值研究

    Institute of Scientific and Technical Information of China (English)

    王寅; 童俊容; 何凤; 罗正茂; 张虹

    2011-01-01

    Objective:To explore the value of urine NGAL and N - acetyl - p - D - glucosaminidase in diagnosing early injury of IgA nephropathy. Methods: 85 patients with lgA nephropathy were categorized into two groups ( Hass I - II group and Hass III~ V group). 30 healthy subjects were recruited as controls. Ungal and Unag were detected by commercial available ELISA kit according to the manufacturer's instructions. And the ratio of Ungal/Cr and Unag/Cr were calculated. Receiver operating characteristic (ROC) curve analysis was used to evaluat the two on the sensitivity and specificity of diagnosis on IgA nephropathy. The area under the ROC curve and the best diagnostic cut -off value were calculated. Results: The levels of Ungal,Unag,Un-GAL/Cr and Unag/Cr are significantly higher in IgAN patients than in control group. The area under ROC curve of Ungal/Cr and Unag/Cr were 0.941 and 0.846 respectively. The best diagnostic cut - off value were 3.50 g /mmol Cr and 1.20 U /mmol Cr. Taking the boundary value to diagnose IgA nephropathy, the sensitivity and specificity for Ungal/Cr and Unag/Cr were 91.2% , 93.7% and 83.3% , 84.9% respectively. Conclusion: Ungal is an objective indicator of early renal damage in IgA nephropathy. Ungal/Cr has higher sensitivity and specificity for the diagnosis of IgA nephropathy than Unag /Cr,and it is expected to be diagnostic indicator for IgA nephropathy.%目的:探讨尿中性粒细胞明胶酶相关脂蛋白(neutrophil gelatinase associated lipocalin,NGAL)和N-乙酰-β-D-氨基葡萄糖苷酶(N - acetyl -β-D - glucosaminidase,NAG)对IgA肾病早期诊断价值.方法:选择IgA肾病患者85例,根据Hass分级Hass Ⅰ~Ⅱ(A组)40例、Hass Ⅲ~V(B组)45例;正常对照组30例.应用ELISA法检测尿液NGAL(uNGAL)和uNAG的浓度,并计算uNGAL/Cr比值和uNAG/Cr比值,进而对uNGAL/Cr和uNAG/Cr进行受试者工作特征(ROC)曲线分析,计算ROC曲线下面积和最佳诊断界值.结果:IgA肾病患者的uNGAL、uNAG、uNGAL/Cr

  9. Activity Detection of GalNAc Transferases by Protein-Based Fluorescence Sensors In Vivo.

    Science.gov (United States)

    Song, Lina; Bachert, Collin; Linstedt, Adam D

    2016-01-01

    Mucin-type O-glycosylation occurring in the Golgi apparatus is an important protein posttranslational modification initiated by up to 20 GalNAc-transferase isozymes with largely distinct substrate specificities. Regulation of this enzyme family affects a vast array of proteins transiting the secretory pathway and misregulation causes human diseases. Here we describe the use of protein-based fluorescence sensors that traffic in the secretory pathway to monitor GalNAc-transferase activity in living cells. The sensors can either be "pan" or isozyme specific.

  10. Mapping of amino acid substitutions conferring herbicide resistance in wheat glutathione transferase.

    Science.gov (United States)

    Govindarajan, Sridhar; Mannervik, Bengt; Silverman, Joshua A; Wright, Kathy; Regitsky, Drew; Hegazy, Usama; Purcell, Thomas J; Welch, Mark; Minshull, Jeremy; Gustafsson, Claes

    2015-03-20

    We have used design of experiments (DOE) and systematic variance to efficiently explore glutathione transferase substrate specificities caused by amino acid substitutions. Amino acid substitutions selected using phylogenetic analysis were synthetically combined using a DOE design to create an information-rich set of gene variants, termed infologs. We used machine learning to identify and quantify protein sequence-function relationships against 14 different substrates. The resulting models were quantitative and predictive, serving as a guide for engineering of glutathione transferase activity toward a diverse set of herbicides. Predictive quantitative models like those presented here have broad applicability for bioengineering.

  11. Origin and evolution of the Peptidyl Transferase Center from proto-tRNAs

    Directory of Open Access Journals (Sweden)

    Sávio T. Farias

    2014-01-01

    Full Text Available We tested the hypothesis of Tamura (2011 [3] that molecules of tRNA gave origin to ribosomes, particularly to the Peptidyl Transferase Center (PTC of the 23S ribosomal RNA. We reconstructed the ancestral sequences from all types of tRNA and compared them in their sequences with the current PTC of 23S ribosomal RNA from different organisms. We built an ancestral sequence of proto-tRNAs that showed a remarkable overall identity of 50.53% with the catalytic site of PTC. We conclude that the Peptidyl Transferase Center was indeed originated by the fusion of ancestral sequences of proto-tRNA.

  12. Espectroscopia multivoxel com tempo de eco curto: a razão colina/N-acetil-aspartato e a graduação dos astrocitomas cerebrais Multivoxel spectroscopy with short echo time: choline/N-acetyl-aspartate ratio and the grading of cerebral astrocytomas

    Directory of Open Access Journals (Sweden)

    Maria de Fátima Vasco Aragão

    2007-06-01

    Full Text Available Avaliou-se a relação colina/N-acetil-aspartato (Co/NAA, obtida pela espectroscopia multivoxel com tempo de eco (TE curto, na graduação histológica dos astrocitomas encefálicos (graus I, II e III-IV, comparando com o parênquima cerebral normal. Observou-se aumento significativo (pThe choline/N-acetyl-aspartate (Cho/NAA ratio, obtained by the multivoxel spectroscopy with short echo time (TE, was evaluated, in the histological grading of the brain astrocytomas (grades I, II and III-IV in comparison with the normal cerebral parenchyma. A significant increase (p<0.05 in the average ratios of Cho/NAA was observed in the three astrocytoma groups studied in relation to normal tissue, having a tendency to increase with the increase in grading, without any statistic significance, which corresponded to: 0.53±0.24 in the control group, 1.19±0.49 in grade I, 1.58±0.65 in grade II and 5.13±8.12 in the high grade group (grades III-IV, with variation in the values encountered. There was an increase in the Cho/NAA ratio in 4/5 (80% in grade I, 5/6 (83% in grade II and 10/20 (50% in grades III and IV. We conclude that multivoxel spectroscopy with short TE can be used in discriminating between normal parenchyma and neoplasm tissue. However, not all neoplasm tissue studied presented an increase in Cho/NAA, especially in the group with higher grade of malignancy.

  13. Electrocatalytic oxidation and its Electroanalytical method of N- Acetyl- L- Cysteine at multi- wall carbon nanotubes modified glassy carbon electrode%N-乙酰-L-半胱氨酸在多壁碳纳米管修饰玻碳电极上的电催化氧化及电分析方法

    Institute of Scientific and Technical Information of China (English)

    任超超; 高作宁

    2009-01-01

    目的:研究了N-乙酰-L-半胱氨酸(N-Acetyl-L-Cysteine,NAC)在多壁碳纳米管修饰玻碳电极(MWCNT/GCE)上的电化学行为及电分析方法.方法:运用循环伏安法(CV)、计时库仑法(Cc)、计时电流法(CA)、线性扫描伏安法(LSV).结果:NAC在GCE上的直接电化学氧化十分迟缓,无氧化峰出现,而在MWCNT/GCE上于0.15 V处出现一个不可逆氧化峰.研究了实验条件对NAC电化学行为的影响.测定了电催化过程动力学参数:扩散系数D为5.26×10-5cm2·s-1,电子转移系数α为0.55,电极反应速率常数kf为7.95×10-3 s-1.对含NAC的药物进行电化学定量测定,RSD%在1.2%~2.4%之间,加标回收率在101.6%~102.2%之间.结论:MWCNT/GCE对NAC具有良好的电催化氧化作用,是一受扩散控制的不可逆电催化氧化过程,对NAC样品含量进行电化学定量测定,测定结果令人满意.

  14. China's Consumption Rises

    Institute of Scientific and Technical Information of China (English)

    Richard Zhu

    2011-01-01

    @@ The consumption in China is surging and Chinese consumers are more confident about their future this year despite the inflationary backdrop, according to the 2011 Annual Chinese Consumer Study by McKinsey & Co released recently. The survey estimates that by 2020 and within the course of one decade, real consumption will have doubled to $4.8 trillion and China will then be the world's second-biggest consumer market after the United States.Yet in some respects, private consumption remains stubbornly low.

  15. Marriage and Consumption

    DEFF Research Database (Denmark)

    Blow, Laura; Browning, Martin; Ejrnæs, Mette

    We examine theoretically and empirically consumption over the early part of the life-cycle. The main focus is on the transition from being single to living with someone else. Our theoretical model allows for publicness in consumption; uncertainty concerning marriage; differences between lifetime...... incomes for prospective partners and a marriage premium. We develop a two period model to bring out the main features of the impact of marriage on consumption and saving. We then develop a multi-period model that can be taken to the data on expenditures by singles and couples aged between 18 and 30. Our...

  16. Energy-consumption modelling

    Energy Technology Data Exchange (ETDEWEB)

    Reiter, E.R.

    1980-01-01

    A highly sophisticated and accurate approach is described to compute on an hourly or daily basis the energy consumption for space heating by individual buildings, urban sectors, and whole cities. The need for models and specifically weather-sensitive models, composite models, and space-heating models are discussed. Development of the Colorado State University Model, based on heat-transfer equations and on a heuristic, adaptive, self-organizing computation learning approach, is described. Results of modeling energy consumption by the city of Minneapolis and Cheyenne are given. Some data on energy consumption in individual buildings are included.

  17. The Consumption Paradigm in Marketing

    OpenAIRE

    Ardianto, Eka

    2003-01-01

    This article elaborates consumption paradigm in marketing. In background, this paper reviews different perspectives of consumption: economic perspective and marketing perspective. In ontology, this work describes various issues regarding consumption view. In epistemology, this article demonstrates how marketers especially researches explore the consumption phenomena. In methodology, the article describes experiential marketing –one of applied consumption paradigm in marketing, which could be ...

  18. Sustainable consumption and marketing

    NARCIS (Netherlands)

    Dam, van Y.K.

    2016-01-01

    Sustainable development in global food markets is hindered by the discrepancy between positive consumer attitudes towards sustainable development or sustainability and the lack of corresponding sustainable consumption by a majority of consumers. Apparently for many (light user) consumers the ‘

  19. Why Taxing Consumption?

    DEFF Research Database (Denmark)

    Landes, Xavier

    2015-01-01

    are controversial while the invocation of efficiency is actually grounded in an underlying view of social cooperation. Secondly, this chapter advances the idea that an ultimate justification for the choice of specific tax base (consumption, income and wealth) expresses such an underlying view. In other words......, the choice of a specific tax base is not totally instrumental, it has some intrinsic moral value too. In this respect, the chapter ends with a comparison between taxing income and taxing consumption. It is shown that a tax on consumption raises questions that should be answered by political philosophers.......Robert Frank is famous for proposing an incremental tax on consumption. His proposition is motivated by the control of positional externalities, i.e. the costs that individuals impose on each other when they consume goods for securing or acquiring social status. A close analysis of Frank...

  20. Sustainable consumption and marketing

    NARCIS (Netherlands)

    Dam, van Y.K.

    2016-01-01

    Sustainable development in global food markets is hindered by the discrepancy between positive consumer attitudes towards sustainable development or sustainability and the lack of corresponding sustainable consumption by a majority of consumers. Apparently for many (light user) consumers the

  1. Marriage and Consumption

    DEFF Research Database (Denmark)

    Blow, Laura; Browning, Martin; Ejrnæs, Mette

    We examine theoretically and empirically consumption over the early part of the life-cycle. The main focus is on the transition from being single to living with someone else. Our theoretical model allows for publicness in consumption; uncertainty concerning marriage; differences between lifetime...... incomes for prospective partners and a marriage premium. We develop a two period model to bring out the main features of the impact of marriage on consumption and saving. We then develop a multi-period model that can be taken to the data on expenditures by singles and couples aged between 18 and 30. Our...... empirical work is based on individual based quasi-panels from UK expenditure survey data from 1978 to 2005. The model fits the data relatively well. We find that expenditure by couples leads to 20-40 % more consumption than the same expenditure split between two comparable singles....

  2. Work-related consumption drivers and consumption at work

    DEFF Research Database (Denmark)

    Røpke, Inge

    2004-01-01

    The main message in this paper is that the discussion on sustainable consumption should also incorporate the consumption that occurs in relation to work and, more generally, the relationship between consumption at work and consumption at home. I start by considering how domestic consumption...... is encouraged by work-related factors and continue to consider how consumption activities occur in the workplace, so illustrating that production and consumption are intertwined. The main part of the paper deals in detail with the conceptual distinction between production and consumption. Inspiration is drawn...

  3. Work-related consumption drivers and consumption at work

    DEFF Research Database (Denmark)

    Røpke, Inge

    2004-01-01

    The main message in this paper is that the discussion on sustainable consumption should also incorporate the consumption that occurs in relation to work and, more generally, the relationship between consumption at work and consumption at home. I start by considering how domestic consumption...... is encouraged by work-related factors and continue to consider how consumption activities occur in the workplace, so illustrating that production and consumption are intertwined. The main part of the paper deals in detail with the conceptual distinction between production and consumption. Inspiration is drawn...

  4. Cracking the Consumption Nut

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ Increasing domestic consumption has become a hot topic filtering through various economic circles in China.In the aftermath of the global financial crisis,the call has gone out to emphasize consumption and downplay saving among people in the international community.Xia Bin,Director General of the Research Institute of Finance of the Development Research Center of the State Council,made 10suggestions in the Economic Information Daily to achieve this goal.

  5. Consumption and Children

    DEFF Research Database (Denmark)

    Browning, Martin; Ejrnæs, Mette

    2009-01-01

    supply. We develop two tests of the extreme hypothesis that only changes in family structure matter. We estimate effects of the numbers and ages of children on consumption. These estimates allow us to rationalize all of the increase in consumption without recourse to any of the causal mechanisms. Our...... estimates can be interpreted either as giving upper bounds on the effects of children or as evidence that the other causes are not important....

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

    Science.gov (United States)

    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…

  7. Economic theories of sustainable consumption

    NARCIS (Netherlands)

    Ferrer-i-Carbonell, Ada; Bergh, van den Jeroen C.J.M.

    1999-01-01

    The term `sustainable consumption' denotes the search for consumption patterns that reduce human pressure on the environment and nature. This searchinvolves three levels of research. First, the relationship between consumption, lifestyles and environmental sustainability has to be clarified. Agenera

  8. Purification of human hepatic glutathione S-transferases and the development of a radioimmunoassay for their measurement in plasma

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, J.D.; Gilligan, D.; Beckett, G.J. (Edinburgh Univ. (UK). Dept. of Clinical Chemistry); Chapman, B.J. (Royal Infirmary, Edinburgh (UK))

    1983-10-31

    A purification scheme is described for six human hepatic glutathione S-transferases from a single liver. Five of the transferases comprised Ya monomers and had a molecular mass of 44000. The remaining enzyme comprised Yb monomers and had a molecular mass of 47000. Data are presented demonstrating that there are at least two distinct Ya monomers. A radioimmunoassay has been developed that has sufficient precision and sensitivity to allow direct measurement of glutathione S-transferase concentrations in unextracted plasma. A comparison of aminotransferase and glutathione S-transferase levels, in three patients who had taken a paracetamol overdose, indicated that glutathione S-transferase measurements provided a far more sensitive index of hepatocellular integrity than the more conventional aminotransferase measurements.

  9. Partial hypoxanthine-guanine phosphoribosyl transferase deficiency without elevated urinary hypoxanthine excretion

    NARCIS (Netherlands)

    van Dael, C. M. L.; Pierik, L. J. W. M.; Reijngoud, D. J.; Niezen-Koning, K. E.; van Diggelen, O. P.; van Spronsen, F. J.

    Partial hypoxanthine-guanine phosphoribosyl transferase (HGPRT) deficiency, also known as the Kelley-Seegmiller syndrome, can give rise to a wide range of neurological symptoms, and renal insufficiency. Biochemically, it is characterized by high uric acid concentrations in blood, high uric acid and

  10. Antibiotic inhibition of the movement of tRNA substrates through a peptidyl transferase cavity

    DEFF Research Database (Denmark)

    Porse, B T; Rodriguez-Fonseca, C; Leviev, I

    1996-01-01

    The present review attempts to deal with movement of tRNA substrates through the peptidyl transferase centre on the large ribosomal subunit and to explain how this movement is interrupted by antibiotics. It builds on the concept of hybrid tRNA states forming on ribosomes and on the observed movem...

  11. Development of isoform-specific sensors of polypeptide GalNAc-transferase activity.

    Science.gov (United States)

    Song, Lina; Bachert, Collin; Schjoldager, Katrine T; Clausen, Henrik; Linstedt, Adam D

    2014-10-31

    Humans express up to 20 isoforms of GalNAc-transferase (herein T1-T20) that localize to the Golgi apparatus and initiate O-glycosylation. Regulation of this enzyme family affects a vast array of proteins transiting the secretory pathway and diseases arise upon misregulation of specific isoforms. Surprisingly, molecular probes to monitor GalNAc-transferase activity are lacking and there exist no effective global or isoform-specific inhibitors. Here we describe the development of T2- and T3-isoform specific fluorescence sensors that traffic in the secretory pathway. Each sensor yielded little signal when glycosylated but was strongly activated in the absence of its glycosylation. Specificity of each sensor was assessed in HEK cells with either the T2 or T3 enzymes deleted. Although the sensors are based on specific substrates of the T2 and T3 enzymes, elements in or near the enzyme recognition sequence influenced their activity and required modification, which we carried out based on previous in vitro work. Significantly, the modified T2 and T3 sensors were activated only in cells lacking their corresponding isozymes. Thus, we have developed T2- and T3-specific sensors that will be valuable in both the study of GalNAc-transferase regulation and in high-throughput screening for potential therapeutic regulators of specific GalNAc-transferases.

  12. 21 CFR 573.130 - Aminoglycoside 3′-phospho- transferase II.

    Science.gov (United States)

    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...) which catalyzes the phosphorylation of certain aminoglycoside antibiotics, including kanamycin,...

  13. Effect of glutathione S-transferases on the survival of patients with acute myeloid leukaemia

    DEFF Research Database (Denmark)

    Autrup, Judith; Hokland, Peter; Pedersen, Lars

    2002-01-01

    The objective of the study was to investigate the effect of genetic polymorphisms in glutathione S-transferases (GST) on the survival of acute myeloid leukaemia patients receiving adriamycin induction therapy. A total of 89 patients were included in the study. Patients who carried at least one GS...

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

    Science.gov (United States)

    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...

  15. Glutathione transferase activity and oocyte development in copepods exposed to toxic phytoplankton

    DEFF Research Database (Denmark)

    Kozlowsky-Suzuki, Betina; Koski, Marja; Hallberg, Eric

    2009-01-01

    Organisms present a series of cellular mechanisms to avoid the effects of toxic compounds. Such mechanisms include the increase in activity of detoxification enzymes [e.g., 7-ethoxyresorufin-O-deethylase (EROD) and glutathione S-transferase (GST)I, which could explain the low retention of ingeste...

  16. Glutathione S-transferase polymorphisms in allergic contact dermatitis to xenobiotics

    NARCIS (Netherlands)

    Pot, L.M.; Alizadeh, B.Z.; Laizane, D.; Coenraads, P.J.; Snieder, H.; Blömeke, B.

    2010-01-01

    Background: Xenobiotics, such as para-phenylenediamine (PPD), are thought to be detoxified by phase II enzymes, like the Glutathione S-transferases (GSTs). The human cytosolic GSTs display polymorphisms which are likely to contribute to interindividual differences in responses to xenobiotics. By per

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

    Energy Technology Data Exchange (ETDEWEB)

    Boone, Christopher D.; Zhong, Guo; Smeltz, Marci; James, Margaret O., E-mail: mojames@ufl.edu; McKenna, Robert, E-mail: mojames@ufl.edu

    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°.

  18. A practical fluorogenic substrate for high-throughput screening of glutathione S-transferase inhibitors.

    Science.gov (United States)

    Fujikawa, Yuuta; Morisaki, Fumika; Ogura, Asami; Morohashi, Kana; Enya, Sora; Niwa, Ryusuke; Goto, Shinji; Kojima, Hirotatsu; Okabe, Takayoshi; Nagano, Tetsuo; Inoue, Hideshi

    2015-07-21

    We report a new fluorogenic substrate for glutathione S-transferase (GST), 3,4-DNADCF, enabling the assay with a low level of nonenzymatic background reaction. Inhibitors against Noppera-bo/GSTe14 from Drosophila melanogaster were identified by high throughput screening using 3,4-DNADCF, demonstrating the utility of this substrate.

  19. Partial hypoxanthine-guanine phosphoribosyl transferase deficiency without elevated urinary hypoxanthine excretion

    NARCIS (Netherlands)

    van Dael, C. M. L.; Pierik, L. J. W. M.; Reijngoud, D. J.; Niezen-Koning, K. E.; van Diggelen, O. P.; van Spronsen, F. J.

    2007-01-01

    Partial hypoxanthine-guanine phosphoribosyl transferase (HGPRT) deficiency, also known as the Kelley-Seegmiller syndrome, can give rise to a wide range of neurological symptoms, and renal insufficiency. Biochemically, it is characterized by high uric acid concentrations in blood, high uric acid and

  20. Molecular cloning and expression of several new Anopheles cracens epsilon class glutathione transferases.

    Science.gov (United States)

    Wongtrakul, Jeerang; Wongsantichon, Jantana; Vararattanavech, Ardcharaporn; Leelapat, Posri; Prapanthadara, La-aied; Ketterman, Albert J

    2009-01-01

    Glutathione transferases, GSTs, are detoxification proteins that are found in most organisms. The acGSTE3-3 had the ability to conjugate 4-hydroxynonenal, a cytotoxic lipid peroxidation product. Although other Epsilon GSTs showed roles in insecticide metabolism, the acGSTE3-3 appeared to have a major role in detoxifying lipid peroxidation products conferring protection against oxidative damage.

  1. Chromosomal localization of the gene for the human Theta class glutathione transferase (GSTT1)

    Energy Technology Data Exchange (ETDEWEB)

    Webb, G.; Vaska, V. [Queen Elizabeth Hospital, Adelaide (Australia); Goggan, M.; Board, P. [Australian National Univ., Canberra (Australia)

    1996-04-01

    Two loci encoding Theta class glutathione transferases (GSTs) have been identified in humans. In situ hybridization studies have localized the GSTT1 gene to 22q11.2. This is the same band to which we previously localized the GSTT2 gene. This finding confirms the trend for human GST genes to be found in class-specific clusters. 20 refs., 1 fig.

  2. Maize white seedling 3 results from disruption of homogentisate solanesyl transferase

    Science.gov (United States)

    Maize white seedling 3 (w3) has served as a model albino-seedling mutant since its discovery in 1923. We show here 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 re...

  3. Development of isoform-specific sensors of polypeptide GalNAc-transferase activity

    DEFF Research Database (Denmark)

    Song, Lina; Bachert, Collin; Schjoldager, Katrine T

    2014-01-01

    Humans express up to 20 isoforms of GalNAc-transferase (herein T1-T20) that localize to the Golgi apparatus and initiate O-glycosylation. Regulation of this enzyme family affects a vast array of proteins transiting the secretory pathway and diseases arise upon misregulation of specific isoforms...

  4. Inhibition of rat, mouse, and human glutathione S-transferase by eugenol and its oxidation products

    NARCIS (Netherlands)

    Rompelberg, C.J.M.; Ploemen, J.H.T.M.; Jespersen, S.; Greef, J. van der; Verhagen, H.; Bladeren, P.J. van

    1996-01-01

    The irreversible and reversible inhibition of glutathione S-transferases (GSTs) by eugenol was studied in rat, mouse and man. Using liver cytosol of human, rat and mouse, species differences were found in the rate of irreversible inhibition of GSTs by eugenol in the presence of the enzyme tyrosinase

  5. Galactose-1-phosphate uridyl transferase deficiency is not associated with Mullerian aplasia in Dutch patients.

    NARCIS (Netherlands)

    Nijland, R.; Hartog, F.E.; Wevers, R.A.; Wanders, R.J.; Willemsen, W.N.P.

    2009-01-01

    STUDY OBJECTIVE: To study whether a deficiency in galactose-1-phosphate uridyl transferase (GALT) activity of mothers was an explanation for the occurrence of Mullerian aplasia of their daughters. DESIGN: A case control study. SETTING: The patients were selected from the outpatient clinic of the Uni

  6. Glutathione S-transferase isoenzymes in relation to their role in detoxification of xenobiotics.

    NARCIS (Netherlands)

    Vos, R.M.E.

    1989-01-01

    The glutathione S-transferases (GST) are a family of isoenzymes serving a major part in the biotransformation of many reactive compounds. The isoenzymes from rat, man and mouse are divided into three classes, alpha, mu and pi, on the basis of similar structural and enzymatic properties.

  7. Functional characterization of glutathione S-transferases associated with insecticide resistance in Tetranychus urticae

    NARCIS (Netherlands)

    Pavlidi, N.; Tseliou, V.; Riga, M.; Nauen, R.; Van Leeuwen, T.; Labrou, N.E.; Vontas, J.

    2015-01-01

    The two-spotted spider mite Tetranychus urticae is one of the most important agricultural pests world-wide. It is extremely polyphagous and develops resistance to acaricides. The overexpression of several glutathione S-transferases (GSTs) has been associated with insecticide resistance. Here, we fun

  8. Functional characterization of glutathione S-transferases associated with insecticide resistance in Tetranychus urticae

    NARCIS (Netherlands)

    Pavlidi, N.; Tseliou, V.; Riga, M.; Nauen, R.; Van Leeuwen, T.; Labrou, N.E.; Vontas, J.

    2015-01-01

    The two-spotted spider mite Tetranychus urticae is one of the most important agricultural pests world-wide. It is extremely polyphagous and develops resistance to acaricides. The overexpression of several glutathione S-transferases (GSTs) has been associated with insecticide resistance. Here, we

  9. Inhibition of human glutathione S-transferase P1-1 by the flavonoid quercetin

    NARCIS (Netherlands)

    Zanden, J.J. van; Hamman, O.B.; Iersel, M.L.P.S. van; Boeren, S.; Cnubben, N.H.P.; Lo Bello, M.; Vervoort, J.; Bladeren, P.J. van; Rietjens, I.M.C.M.

    2003-01-01

    In the present study, the inhibition of human glutathione S-transferase P1-1 (GSTP1-1) by the flavonoid quercetin has been investigated. The results show a time- and concentration-dependent inhibition of GSTP1-1 by quercetin. GSTP1-1 activity is completely inhibited upon 1 h incubation with 100 μM q

  10. The phosphopantetheinyl transferases: catalysis of a post-translational modification crucial for life

    DEFF Research Database (Denmark)

    Beld, Joris; Sonnenschein, Eva; Vickery, Christopher R.;

    2013-01-01

    Covering: up to 2013 Although holo-acyl carrier protein synthase, AcpS, a phosphopantetheinyl transferase (PPTase), was characterized in the 1960s, it was not until the publication of the landmark paper by Lambalot et al. in 1996 that PPTases garnered wide-spread attention being classified as a d...

  11. Acetate:succinate CoA-transferase in the hydrogenosomes of Trichomonas vaginalis: Identification and characterization

    NARCIS (Netherlands)

    K.W.A. Grinsven; S. Rosnowsky (Silke); S.W.H. van Weelden (Susanne); S. Pütz (Simone); M. van der Giezen (Mark); W. Martin (William); J.J. van Hellemond (Jaap); A.G.M. Tielens (Aloysius); K. Henze (Katrin)

    2008-01-01

    textabstractAcetate:succinate CoA-transferases (ASCT) are acetate-producing enzymes in hydrogenosomes, anaerobically functioning mitochondria and in the aerobically functioning mitochondria of trypanosomatids. Although acetate is produced in the hydrogenosomes of a number of anaerobic microbial euka

  12. Ethical Food Consumption

    DEFF Research Database (Denmark)

    Heerwagen, Lennart Ravn

    So-called ‘ethical’ food products have spread across the industrialised world. These are products that are produced under labelling schemes with extraordinary attentiveness to issues such as farm animal welfare and environmental protection. Political decision-makers and other stakeholders in food...... protection. In particular, it aims to examine the concrete improvements that may be pursued through markets for ethical food, and how these improvements are influenced by factors related to individual consumers’ choice of food. This thesis is structured around three research papers that illuminate different...... aspects of ethical food consumption and, based on this, provide concrete policy inputs. The scope of the research is highly interdisciplinary, and includes perspectives from ethics and the social sciences on food consumption. Paper I: Can increased organic consumption mitigate climate changes...

  13. Estimation of food consumption

    Energy Technology Data Exchange (ETDEWEB)

    Callaway, J.M. Jr.

    1992-04-01

    The research reported in this document was conducted as a part of the Hanford Environmental Dose Reconstruction (HEDR) Project. The objective of the HEDR Project is to estimate the radiation doses that people could have received from operations at the Hanford Site. Information required to estimate these doses includes estimates of the amounts of potentially contaminated foods that individuals in the region consumed during the study period. In that general framework, the objective of the Food Consumption Task was to develop a capability to provide information about the parameters of the distribution(s) of daily food consumption for representative groups in the population for selected years during the study period. This report describes the methods and data used to estimate food consumption and presents the results developed for Phase I of the HEDR Project.

  14. Consumption and Needs

    DEFF Research Database (Denmark)

    Læssøe, Jeppe

    1996-01-01

    The contribution takes its point of departure in the relation between the many resource savings initiatives and the lack of interest for the growth in consumption. It argues that what we make up on the roundabouts, we risk to loose on the swings. In order to prevent that it reveals some of the cu......The contribution takes its point of departure in the relation between the many resource savings initiatives and the lack of interest for the growth in consumption. It argues that what we make up on the roundabouts, we risk to loose on the swings. In order to prevent that it reveals some...... of the cultural and psychological dynamics behind the need for increased consumption i modern societies. It implies discussions of the fallback from citizen to consumer, the trend toward individualization and the experience of lack of time. The point is that urban ecology has to be revised in order to take th...

  15. Role of genetic polymorphism of glutathione-s-transferase T1 and microsomal epoxide hydrolase in aflatoxin-associated hepatocellular carcinoma

    NARCIS (Netherlands)

    Tiemersma, E.W.; Omer, R.E.; Bunschoten, A.; van't Veer, P.; Kok, F.J.; Idrsi, M.O.; Kampman, E.

    2001-01-01

    Exposure to aflatoxins is a risk factor for hepatocellular carcinoma (HCC). Aflatoxins occur in peanut butter and are metabolized by genetically polymorphic enzymes such as glutathione-S-transferases encoded by glutathione-S-transferase mu 1 gene (GSTM1) and glutathione-S-transferase theta 1 gene (G

  16. Changes in cultural consumption

    DEFF Research Database (Denmark)

    Navarrete, T.; Borowiecki, K. J.

    2016-01-01

    Visits to museums have been studied as hedonic and utilitarian forms of cultural consumption, though limited attention has been given to the access of museum collections online. We perform a unique historic analysis of the visibility of collections in a museum of ethnographic collections and comp......Visits to museums have been studied as hedonic and utilitarian forms of cultural consumption, though limited attention has been given to the access of museum collections online. We perform a unique historic analysis of the visibility of collections in a museum of ethnographic collections...

  17. Why Taxing Consumption?

    DEFF Research Database (Denmark)

    Landes, Xavier

    2015-01-01

    Robert Frank is famous for proposing an incremental tax on consumption. His proposition is motivated by the control of positional externalities, i.e. the costs that individuals impose on each other when they consume goods for securing or acquiring social status. A close analysis of Frank...... are controversial while the invocation of efficiency is actually grounded in an underlying view of social cooperation. Secondly, this chapter advances the idea that an ultimate justification for the choice of specific tax base (consumption, income and wealth) expresses such an underlying view. In other words...

  18. Proper Islamic Consumption

    DEFF Research Database (Denmark)

    Fischer, Johan

    ”. It is a must-read for researchers and students alike, especially those who want to pursue their study on the middle class, Islam and consumption.' Reviewed by Prof. Abdul Rahman Embong, Asian Anthropology    'This volume does make an important contribution to our understanding of the responses of socially...... spite of a long line of social theory analyzing the spiritual in the economic, and vice versa, very little of the recent increase in scholarship on Islam addresses its relationship with capitalism. Johan Fischer’s book,Proper Islamic Consumption, begins to fill this gap. […] Fischer’s detailed...

  19. Hydrothermal synthesis of N-acetyl-L-crysteine stabilized Cd_xZn_(1-x)Se quantum dots%水热法合成N-乙酰-L-半胱氨酸稳定的Cd_xZn_(1-x)Se合金量子点

    Institute of Scientific and Technical Information of China (English)

    顾乐民; 胡朗; 姚爱华; 王德平

    2011-01-01

    In this paper,ZnxCd1-xSe quantum dots with tunable photoluminescence emission,uniform particle size and good crystallinity were synthesized by hydrothermal method,in which N-acetyl-L-crysteine was used as a stabilizer.UV-Vis absorption spectroscopy(UV-Vis),photoluminescence(PL) spectroscopy,X-ray diffraction(XRD) spectroscopy,and high-resolution transmission electron microscopy were used to characterize their structures and properties.The effects of Cd2+/Zn2+ ratio,pH of the precursor solution,hydrothermal temperature and time on the photoluminescence properties of ZnxCd1-xSe quantum dots were significantly investigated in the present work.The results showed that the obtaining quantum dots possessed high photoluminescence yield(up to 35%) and narrow fluorescence full-width(FWHM50nm).Therefore,the ZnxCd1-xSe quantum dots would be a promising fluorescent probe for biological and biomedical imaging.%采用了N-乙酰-L-半胱氨酸为稳定剂,通过水热法制备了荧光发射峰可调、粒径均匀且结晶性能良好的ZnxCd1-xSe合金量子点,并采用紫外-可见光吸收光谱(UV-Vis)、荧光光谱(PL)、X射线衍射(XRD)、高分辨透射电镜(HRTEM)等对其结构和性能进行了表征。重点研究了Cd2+/Zn2+比值、初始溶液pH值、水热反应温度和时间等实验条件对ZnxCd1-xSe量子点荧光性能的影响。研究表明所制备的量子点荧光量子产率高(35%),荧光发射谱半峰宽窄(FWHM〈50nm),有望作为生物荧光标记物。

  20. N-acetil-β-D-glicosaminidase como biomarcador precoce de disfunção renal para a exposição ocupacional ao chumbo inorgânico N-acetyl-β-D-glucosaminidase as an early biomarker of renal dysfunction due to occupational exposure to inorganic lead

    Directory of Open Access Journals (Sweden)

    Leandro Nishikawa Gonçales

    2008-08-01

    Full Text Available OBJETIVO: Este estudo teve como objetivo averiguar a atividade enzimática da N-acetil-β-D-glicosaminidase (NAG como possível biomarcador precoce de disfunção renal para a exposição ocupacional ao chumbo inorgânico. MATERIAIS E MÉTODOS: Foi selecionado um grupo de 30 pessoas do sexo masculino expostas ao chumbo inorgânico em uma fábrica de baterias localizada no estado do Paraná. Fizeram parte do grupo os funcionários que mostraram valores de chumbo sanguíneo inferiores a 40 mg/dl. O grupo controle foi representado por 15 adultos saudáveis com similaridade em relação à idade e ao gênero do grupo exposto. Foram determinados os níveis de plumbemia, do ácido d-aminolevulínico urinário e a atividade da NAG urinária. RESULTADOS E DISCUSSÃO: Foi evidenciado que a atividade urinária da NAG foi significativamente maior (p OBJECTIVE: This study aimed to verify the enzymatic activity of N-acetyl-β-D-glucosaminidase (NAG as a possible early biomarker of renal dysfunction due to occupational exposure to inorganic lead. MATERIALS AND METHODS: We selected a group of 30 males that had been exposed to inorganic lead in a battery factory in the state of Paraná. This group comprised those employees whose blood lead levels were below 40 mg/dl. The control group consisted of 15 healthy adults of similar age and gender compared with the exposed group. Blood lead concentrations, d-aminolevulinic acid levels and urinary NAG activity were measured. RESULTS AND DISCUSSION: It was shown that urinary NAG activity was significantly higher (p < 0.05, U test of Mann-Whitney in the exposed group in comparison to the control group, and there was a significant negative correlation (p < 0.05, Spearman Rank Order correlation between the biological indicator of lead exposure and urinary NAG activity. CONCLUSION: The results showed that the increase of urinary NAG activity may be used as an early biomarker of the exposure to inorganic lead.

  1. Effects of diluter ingredient on the alkaline N-acetyl-β-D-glucosaminidase from porcine semen%稀释液成分对猪精液碱性N-乙酰-β-D-氨基葡萄糖苷酶的影响

    Institute of Scientific and Technical Information of China (English)

    林心宇; 胡崇伟; 章文; 翁丽蓉; 罗忠宝; 黄一帆; 黄小红

    2012-01-01

    The effects of main ingredients in semen diluter on N-acetyl-β-D-glucosaminidaseⅡ (NAGase Ⅱ ) from porcine semen were investigated. The results indicated that penicillin potassium and streptomycin sulphate had no effects on the activity of alkaline NAGase. EDTA. 2Na and Vita- min C showed significantly activating effects on the enzyme activity. The lower concentrations glu- cose and sucrose activated the enzyme, while the higher concentrations inhibited the enzyme activi- ty in some degree. Fructose, trisodium citrate,Tris and sodium bicarbonate showed various degrees of inhibitory effects on the enzyme activity. Tris was a reversible non-competitive inhibitor, with inhibition constants of free enzyme(Kr) was 9.81 mmol/L. Sodium bicarbonate was a mixed-type inhibitor. The inhibition constants of free enzyme (K_I) and enzyme-substrate complex (K_IS) with sodium bicarbonate were determined to be 111.18 mmol/L and 26.61 mmol/L,respectively.%以猪精液稀释液主要成分为效应物,研究其对杜洛克猪精液中N-乙酰-β-D-氨基葡萄糖苷酶Ⅱ活力的影响。结果表明:在一定浓度下青霉素钾和硫酸链霉素对酶活力没有影响;EDTA·2Na和维生索C对酶活力有显著的激活作用;葡萄糖和蔗糖对酶活力有先扬后抑的作用;果糖、柠檬酸三钠、三羟甲基氨基甲烷、碳酸氢钠对酶活力则有不同程度的抑制作用;三羟甲基氨基甲烷表现为可逆的非竞争性抑制,抑制常数K1为9.81mmol/L;碳酸氢钠则表现为可逆的混合型抑制,抑制常数K_I和K_ID分别为111.18mmol/L和26.61mmol/L。

  2. 探讨尿N-乙酰-β-D-氨基葡萄糖苷酶检测对原发性肾病综合征的临床价值%Discusses the urine N-acetyl-β-D-amino grape glycosidase to test the application value of the primary nephrotic syndrome

    Institute of Scientific and Technical Information of China (English)

    刘红; 伊力夏提; 岳华; 陆晨; 刘颖; 赵红娟

    2013-01-01

    Objectives To investigate the clinical value of urine NAG in Primary nephrotic syndrome patients.Methods 52 patients with primary nephrotic syndrome were enrolled who were in-patients,dated from December 2008 to May 2011,in patients before and after the use of hormone by colorimetric method to detect the urine NAG,and the detection results compare and statistical analysis.Results Primary nephrotic syndrome patients use hormone therapy,the detection of positive urine NAG for 9.62%,urinary protein qualitative results for (-) ~ +,a statistically significant difference(P < 0.05).Conclusions Urine NAG enzyme detect can as a primary nephrotic syndrome sensitive indexes,the curative judgment and delay the progress of kidney disease has an important clinical significance.%目的 探讨尿N-乙酰-β-D-氨基葡萄糖苷酶(N-acetyl-β-D-glucosa minidase,NAG)检测对原发性肾病综合征患者的临床价值.方法 选择2008年12月~2011年5月在新疆维吾尔自治区人民医院肾病科住院的原发性肾病综合征患者52例为病例组,对患者使用激素前、后采用对硝基苯酚(PNP)比色法检测尿NAG,并对检测结果进行比较及统计学分析.结果 原发性肾病综合征患者使用激素治疗后,检测尿NAG阳性率为9.62%,尿蛋白定性结果为(-)~+,差异具有统计学意义(P<0.05).结论 尿NAG酶检测可以作为原发性肾病综合征的敏感指标,对疗效判断及延缓肾脏疾病的进展具有重要的临床意义.

  3. GalNAc-transferase specificity prediction based on feature selection method.

    Science.gov (United States)

    Lu, Lin; Niu, Bing; Zhao, Jun; Liu, Liang; Lu, Wen-Cong; Liu, Xiao-Jun; Li, Yi-Xue; Cai, Yu-Dong

    2009-02-01

    GalNAc-transferase can catalyze the biosynthesis of O-linked oligosaccharides. The specificity of GalNAc-transferase is composed of nine amino acid residues denoted by R4, R3, R2, R1, R0, R1', R2', R3', R4'. To predict whether the reducing monosaccharide will be covalently linked to the central residue R0(Ser or Thr), a new method based on feature selection has been proposed in our work. 277 nonapeptides from reference [Chou KC. A sequence-coupled vector-projection model for predicting the specificity of GalNAc-transferase. Protein Sci 1995;4:1365-83] are chosen for training set. Each nonapeptide is represented by hundreds of amino acid properties collected by Amino Acid Index database (http://www.genome.jp/aaindex) and transformed into a numeric vector with 4554 features. The Maximum Relevance Minimum Redundancy (mRMR) method combining with Incremental Feature Selection (IFS) and Feature Forward Selection (FFS) are then applied for feature selection. Nearest Neighbor Algorithm (NNA) is used to build prediction models. The optimal model contains 54 features and its correct rate tested by Jackknife cross-validation test reaches 91.34%. Final feature analysis indicates that amino acid residues at position R3' play the most important role in the recognition of GalNAc-transferase specificity, which were confirmed by the experiments [Elhammer AP, Poorman RA, Brown E, Maggiora LL, Hoogerheide JG, Kezdy FJ. The specificity of UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase as inferred from a database of in vivo substrates and from the in vitro glycosylation of proteins and peptides. J Biol Chem 1993;268:10029-38; O'Connell BC, Hagen FK, Tabak LA. The influence of flanking sequence on the O-glycosylation of threonine in vitro. J Biol Chem 1992;267:25010-8; Yoshida A, Suzuki M, Ikenaga H, Takeuchi M. Discovery of the shortest sequence motif for high level mucin-type O-glycosylation. J Biol Chem 1997;272:16884-8]. Our method can be used as a tool for predicting O

  4. Extended Consumption Chain

    Institute of Scientific and Technical Information of China (English)

    Tang Jintao

    2010-01-01

    @@ Expo consumption will drive retail sales, hotel and catering, transportation, real estate,tourism and other industries.The housing rental market began to heat up. In addition, it wiU also benefit from the whole Yangtze River Delta to the whole China.

  5. The Ideology of Consumption

    DEFF Research Database (Denmark)

    Hansen, Brian Benjamin

    2013-01-01

    This article opts for a return to a critique of the ideology of consumption. Following Slavoj Žižek it argues that what must be addressed in present-day consumer-capitalism is the level of the superego. Superego is not about living up to certain norms/standards; rather, superego fits consumerism...

  6. Value Creation and Consumption

    DEFF Research Database (Denmark)

    Taillard, Marie; Voyer, Benjamin; Glaveanu, Vlad Petre

    2014-01-01

    friends in a series of selfies post- ed on Snapchat. With augmented reality technology, combinations of designs and colors can be tried on before an in-store visit, or a friend’s opinion solicited in real time. These examples highlight the fact that consumption is, at its very core, a creative activity...

  7. Organic consumption behavior

    NARCIS (Netherlands)

    Du, Shuili; Bartels, Jos; Reinders, Machiel; Sen, Sankar

    2017-01-01

    Consumer demand for organic food and non-food products has been growing dramatically. This study examines organic consumption behavior from a social identification perspective. Focusing on the central role of organic consumer identification (OCI), or the extent to which individuals categorize

  8. Less Earn, More Consumption?

    Institute of Scientific and Technical Information of China (English)

    Bai Ming

    2010-01-01

    @@ Promoting consumption is a wise move to deal with the international financial crisis Since the international financial crisis broke out in second half of 2008, China had adjusted its macro-economic policies accordingly. Against an unfavorable economic environment,Chinese government decisively determined to "expand domestic demand" in order to "guarantee economic growth" just at the moment the crisis began.

  9. Modification of N-acetyltransferases and glutathione S-transferases by coffee components: possible relevance for cancer risk.

    Science.gov (United States)

    Huber, Wolfgang W; Parzefall, Wolfram

    2005-01-01

    Enzymes of xenobiotic metabolism are involved in the activation and detoxification of carcinogens and can play a pivotal role in the susceptibility of individuals toward chemically induced cancer. Differences in such susceptibility are often related to genetically predetermined enzyme polymorphisms but may also be caused by enzyme induction or inhibition through environmental factors or in the frame of chemopreventive intervention. In this context, coffee consumption, as an important lifestyle factor, has been under thorough investigation. Whereas the data on a potential procarcinogenic effect in some organs remained inconclusive, epidemiology has clearly revealed coffee drinkers to be at a lower risk of developing cancers of the colon and the liver and possibly of several other organs. The underlying mechanisms of such chemoprotection, modifications of xenobiotic metabolism in particular, were further investigated in rodent and in vitro models, as a result of which several individual chemoprotectants out of the >1000 constituents of coffee were identified as well as some strongly metabolized individual carcinogens against which they specifically protected. This chapter discusses the chemoprotective effects of several coffee components and whole coffee in association with modifications of the usually protective glutathione-S-transferase (GST) and the more ambivalent N-acetyltransferase (NAT). A key role is played by kahweol and cafestol (K/C), two diterpenic constituents of the unfiltered beverage that were found to reduce mutagenesis/tumorigenesis by strongly metabolized compounds, such as 2-amino-1-methyl-6-phenylimidazo-[4,5-b]pyridine, 7,12-dimethylbenz[a]anthracene, and aflatoxin B(1), and to cause various modifications of xenobiotic metabolism that were overwhelmingly beneficial, including induction of GST and inhibition of NAT. Other coffee components such as polyphenols and K/C-free coffee are also capable of increasing GST and partially of inhibiting NAT

  10. Glutathione S-transferase polymorphisms, cruciferous vegetable intake and cancer risk in the Central and Eastern European Kidney Cancer Study.

    Science.gov (United States)

    Moore, L E; Brennan, P; Karami, S; Hung, R J; Hsu, C; Boffetta, P; Toro, J; Zaridze, D; Janout, V; Bencko, V; Navratilova, M; Szeszenia-Dabrowska, N; Mates, D; Mukeria, A; Holcatova, I; Welch, R; Chanock, S; Rothman, N; Chow, W-H

    2007-09-01

    High consumption of cruciferous vegetables has been associated with reduced kidney cancer risk in many studies. Isothiocyanates, thought to be responsible for the chemopreventive properties of this food group, are conjugated to glutathione by glutathione S-transferases (GSTs) before urinary excretion. Modification of this relationship by host genetic factors is unknown. We investigated cruciferous vegetable intake in 1097 cases and 1555 controls enrolled in a multicentric case-control study from the Czech Republic, Poland, Romania and Russia. To assess possible gene-diet interactions, genotyped cases (N = 925) and controls (N = 1247) for selected functional or non-synonymous polymorphisms including the GSTM1 deletion, GSTM3 3 bp deletion (IVS6 + 22-AGG) and V224I G>A substitution, GSTT1 deletion and the GSTP1 I105V A>G substitution. The odds ratio (OR) for low (less than once per month) versus high (at least once per week) intake of cruciferous vegetables was 1.29 [95% confidence interval (CI): 1.02-1.62; P-trend = 0.03]. When low intake of cruciferous vegetables (less than once per month) was stratified by GST genotype, higher kidney cancer risks were observed among individuals with the GSTT1 null (OR = 1.86; 95% CI: 1.07-3.23; P-interaction = 0.05) or with both GSTM1/T1 null genotypes (OR = 2.49; 95% CI: 1.08-5.77; P-interaction = 0.05). These data provide additional evidence for the role of cruciferous vegetables in cancer prevention among individuals with common, functional genetic polymorphisms.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-08-01

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

  12. SILENCING THE NUCLEOCYTOPLASMIC O-GLCNAC TRANSFERASE REDUCES PROLIFERATION, ADHESION AND MIGRATION OF CANCER AND FETAL HUMAN COLON CELL LINES

    Directory of Open Access Journals (Sweden)

    AGATA eSTEENACKERS

    2016-05-01

    Full Text Available The post-translational modification of proteins by O-linked β-N-acetylglucosamine (O-GlcNAc is regulated by a unique couple of enzymes. O-GlcNAc transferase (OGT transfers the GlcNAc residue from UDP-GlcNAc, the final product of the hexosamine biosynthetic pathway (HBP, whereas O-GlcNAcase (OGA removes it. This study and others show that OGT and O-GlcNAcylation levels are increased in cancer cell lines. In that context we studied the effect of OGT silencing in the colon cancer cell lines HT29 and HCT116 and the primary colon cell line CCD841CoN. Herein we report that OGT silencing diminished proliferation, in vitro cell survival and adhesion of primary and cancer cell lines. SiOGT dramatically de-creased HT29 and CCD841CoN migration, CCD841CoN harboring high capabilities of mi-gration in Boyden chamber system when compared to HT29 and HCT116. The expression levels of actin and tubulin were unaffected by OGT knockdown but siOGT seemed to disor-ganize microfilament, microtubule and vinculin networks in CCD841CoN. While cancer cell lines harbor higher levels of OGT and O-GlcNAcylation to fulfill their proliferative and migra-tory properties, in agreement with their higher consumption of HBP main substrates glucose and glutamine, our data demonstrate that OGT expression is not only necessary for the biolog-ical properties of cancer cell lines but also for normal cells.

  13. MODE OF ACTION OF LANTANA CAMARA EXTRACTS ON ENZYMES ASPARTATE AMINO TRANSFERASE AND ALANINE AMINO TRANSFERASE ACTIVITY IN TARGET AND NONTARGET ORGANISMS

    Directory of Open Access Journals (Sweden)

    DIVYA RAJAN

    2013-01-01

    Full Text Available The plant Lantana camara on the basis of study conducted found to show effective larvicidal activity. The presentstudy deals with the mode of action of Lantana camara extract on enzymes, Aspartate Amino Transferase andAlanine Amino Transferase activity in target and non-target organisms. The major transaminase system of the bodysuch as AsAT and AlAT were significantly inhibited by the plant extract. A significant decrease in the activity ofabove two enzyme systems were observed from the fourth h of incubation onwards. The transaminase system ofmosquito larvae was more sensitive to Lantana camara extract than that of vertebrate system such as Anabastestudineus and Rana hexadactyla which are the non-target organisms seen in the aquatic habitat. The majortransaminase systems of the body such as AsAT and AlAT were inhibited in a dose dependent manner under bothinvitro and invivo conditions. The change of pH from alkaline (normal larvae to acidic (intoxicated larvae, mayalso be sufficient for inhibiting or blocking most of the enzymatic reactions leading to the death of the organisms.The results of this experiment indicated that the shrub Lantana camara could be studied further in detail and itsbenificial effects to the control of vector bron diseases could be utilised for healthy environments

  14. Lectin Domains of Polypeptide GalNAc Transferases Exhibit Glycopeptide Binding Specificity

    DEFF Research Database (Denmark)

    Pedersen, Johannes W; Bennett, Eric P; Schjoldager, Katrine T-B G;

    2011-01-01

    UDP-GalNAc:polypeptide a-N-acetylgalactosaminyltransferases (GalNAc-Ts) constitute a family of up to 20 transferases that initiate mucin-type O-glycosylation. The transferases are structurally composed of catalytic and lectin domains. Two modes have been identified for the selection...... of glycosylation sites by GalNAc-Ts: confined sequence recognition by the catalytic domain alone, and concerted recognition of acceptor sites and adjacent GalNAc-glycosylated sites by the catalytic and lectin domains, respectively. Thus far, only the catalytic domain has been shown to have peptide sequence...... on sequences of mucins MUC1, MUC2, MUC4, MUC5AC, MUC6, and MUC7 as well as a random glycopeptide bead library, we examined the binding properties of four different lectin domains. The lectin domains of GalNAc-T1, -T2, -T3, and -T4 bound different subsets of small glycopeptides. These results indicate...

  15. Design and synthesis of potent inhibitors of the mono(ADP-ribosyl)transferase, PARP14.

    Science.gov (United States)

    Upton, Kristen; Meyers, Matthew; Thorsell, Ann-Gerd; Karlberg, Tobias; Holechek, Jacob; Lease, Robert; Schey, Garrett; Wolf, Emily; Lucente, Adrianna; Schüler, Herwig; Ferraris, Dana

    2017-07-01

    A series of (Z)-4-(3-carbamoylphenylamino)-4-oxobut-2-enyl amides were synthesized and tested for their ability to inhibit the mono-(ADP-ribosyl)transferase, PARP14 (a.k.a. BAL-2; ARTD-8). Two synthetic routes were established for this series and several compounds were identified as sub-micromolar inhibitors of PARP14, the most potent of which was compound 4t, IC50=160nM. Furthermore, profiling other members of this series identified compounds with >20-fold selectivity over PARP5a/TNKS1, and modest selectivity over PARP10, a closely related mono-(ADP-ribosyl)transferase. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Three-dimensional structure of a Bombyx mori Omega-class glutathione transferase.

    Science.gov (United States)

    Yamamoto, Kohji; Suzuki, Mamoru; Higashiura, Akifumi; Nakagawa, Atsushi

    2013-09-01

    Glutathione transferases (GSTs) are major phase II detoxification enzymes that play central roles in the defense against various environmental toxicants as well as oxidative stress. Here we report the crystal structure of an Omega-class glutathione transferase of Bombyx mori, bmGSTO, to gain insight into its catalytic mechanism. The structure of bmGSTO complexed with glutathione determined at a resolution of 2.5Å reveals that it exists as a dimer and is structurally similar to Omega-class GSTs with respect to its secondary and tertiary structures. Analysis of a complex between bmGSTO and glutathione showed that bound glutathione was localized to the glutathione-binding site (G-site). Site-directed mutagenesis of bmGSTO mutants indicated that amino acid residues Leu62, Lys65, Lys77, Val78, Glu91 and Ser92 in the G-site contribute to catalytic activity.

  17. Structural characterization of the catalytic site of a Nilaparvata lugens delta-class glutathione transferase.

    Science.gov (United States)

    Yamamoto, Kohji; Higashiura, Akifumi; Hossain, Md Tofazzal; Yamada, Naotaka; Shiotsuki, Takahiro; Nakagawa, Atsushi

    2015-01-15

    Glutathione transferases (GSTs) are a major class of detoxification enzymes that play a central role in the defense against environmental toxicants and oxidative stress. Here, we studied the crystal structure of a delta-class glutathione transferase from Nilaparvata lugens, nlGSTD, to gain insights into its catalytic mechanism. The structure of nlGSTD in complex with glutathione, determined at a resolution of 1.7Å, revealed that it exists as a dimer and its secondary and tertiary structures are similar to those of other delta-class GSTs. Analysis of a complex between nlGSTD and glutathione showed that the bound glutathione was localized to the glutathione-binding site. Site-directed mutagenesis of nlGSTD mutants indicated that amino acid residues Ser11, His52, Glu66, and Phe119 contribute to catalytic activity.

  18. Isolation and characterization of Phi class glutathione transferase partial gene from Iranian barley

    Directory of Open Access Journals (Sweden)

    Hassan Mohabatkar

    2012-01-01

    Full Text Available Glutathione transferases are multifunctional proteins involved in several diverse intracellular events such as primary and secondary metabolisms, signaling and stress metabolism. These enzymes have been subdivided into eight classes in plants. The Phi class, being plant specific, is the most represented. In the present study, based on the sequences available at GenBank, different primers were designed for amplifying the Phi class of glutathione transferase gene in the genome and transcriptome of Iranian barley, Karoun cultivar. After extraction of DNA and total RNA, Phi class was amplified and sequenced. Bioinformatics analysis predicted that the deduced protein sequence has two ß-sheets, eight α-helices and some intermediate loops in its secondary structure. Consequently, the sequences were submitted to NCBI GenBank with GS262333 and GW342614 accession numbers. Phylogenic relationships of the sequences were compared with existing sequences in GenBank.

  19. Structural insight into the active site of a Bombyx mori unclassified glutathione transferase.

    Science.gov (United States)

    Hossain, Md Tofazzal; Yamamoto, Kohji

    2015-01-01

    Glutathione transferases (GSTs) are major detoxification enzymes that play central roles in the defense against various environmental toxicants as well as oxidative stress. Here, we identify amino acid residues of an unclassified GST from Bombyx mori, bmGSTu-interacting glutathione (GSH). Site-directed mutagenesis of bmGSTu mutants indicated that amino acid residues Asp103, Ser162, and Ser166 contribute to catalytic activity.

  20. Characterization of human palmitoyl-acyl transferase activity using peptides that mimic distinct palmitoylation motifs.

    OpenAIRE

    Varner, Amanda S; Ducker, Charles E; Xia, Zuping; Zhuang, Yan; De Vos, Mackenzie L; Smith, Charles D.

    2003-01-01

    The covalent attachment of palmitate to proteins commonly occurs on cysteine residues near either N-myristoylated glycine residues or C-terminal farnesylated cysteine residues. It therefore seems likely that multiple palmitoyl-acyl transferase (PAT) activities exist to recognize and modify these distinct palmitoylation motifs. To evaluate this possibility, two synthetic peptides representing these palmitoylation motifs, termed MyrGCK(NBD) and FarnCNRas(NBD), were used to characterize PAT acti...