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Sample records for erythrocyte glucose 6-phosphate

  1. 21 CFR 864.7360 - Erythrocytic glucose-6-phosphate dehydrogenase assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Erythrocytic glucose-6-phosphate dehydrogenase... § 864.7360 Erythrocytic glucose-6-phosphate dehydrogenase assay. (a) Identification. An erythrocytic glucose-6-phosphate dehydrogenase assay is a device used to measure the activity of the enzyme glucose-6...

  2. 21 CFR 864.7360 - Erythrocytic glucose-6-phosphate dehydrogenase assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Erythrocytic glucose-6-phosphate dehydrogenase... § 864.7360 Erythrocytic glucose-6-phosphate dehydrogenase assay. (a) Identification. An erythrocytic glucose-6-phosphate dehydrogenase assay is a device used to measure the activity of the enzyme glucose-6...

  3. 21 CFR 864.7360 - Erythrocytic glucose-6-phosphate dehydrogenase assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Erythrocytic glucose-6-phosphate dehydrogenase... § 864.7360 Erythrocytic glucose-6-phosphate dehydrogenase assay. (a) Identification. An erythrocytic glucose-6-phosphate dehydrogenase assay is a device used to measure the activity of the enzyme glucose-6...

  4. 21 CFR 864.7360 - Erythrocytic glucose-6-phosphate dehydrogenase assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Erythrocytic glucose-6-phosphate dehydrogenase... § 864.7360 Erythrocytic glucose-6-phosphate dehydrogenase assay. (a) Identification. An erythrocytic glucose-6-phosphate dehydrogenase assay is a device used to measure the activity of the enzyme glucose-6...

  5. 21 CFR 864.7360 - Erythrocytic glucose-6-phosphate dehydrogenase assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Erythrocytic glucose-6-phosphate dehydrogenase... § 864.7360 Erythrocytic glucose-6-phosphate dehydrogenase assay. (a) Identification. An erythrocytic glucose-6-phosphate dehydrogenase assay is a device used to measure the activity of the enzyme glucose-6...

  6. Effects of some drugs on human erythrocyte glucose 6-phosphate dehydrogenase: an in vitro study.

    PubMed

    Akkemik, Ebru; Budak, Harun; Ciftci, Mehmet

    2010-12-01

    Inhibitory effects of some drugs on glucose 6-phosphate dehydrogenase from the erythrocytes of human have been investigated. For this purpose, at the beginning, erythrocyte glucose 6-phosphate dehydrogenase was purified 2256 times in a yield of 44.22% by using ammonium sulphate precipitation and 2', 5'-ADP Sepharose 4B affinity gel. Temperature of +4°C was maintained during the purification process. Enzyme activity was determined with the Beutler method by using a spectrophotometer at 340 nm. This method was utilized for all kinetic studies. Ketotifen, dacarbazine, thiocolchicoside, meloxicam, methotrexate, furosemide, olanzapine, methylprednizolone acetate, paricalcitol, ritodrine hydrochloride, and gadobenate-dimeglumine were used as drugs. All the drugs indicated the inhibitory effects on the enzyme. Ki constants for glucose 6-phosphate dehydrogenase were found by means of Lineweaver-Burk graphs. While methylprednizolone acetate showed competitive inhibition, the others displayed non-competitive inhibition. In addition, IC(50) values of the drugs were determined by plotting Activity% vs [I].

  7. Glucose-6-phosphate dehydrogenase

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003671.htm Glucose-6-phosphate dehydrogenase test To use the sharing features on this page, please enable JavaScript. Glucose-6-phosphate dehydrogenase (G6PD) is a protein that ...

  8. Hemizygous Expression of Glucose-6-Phosphate Dehydrogenase in Erythrocytes of Heterozygotes for the Lesch-Nyhan Syndrome*

    PubMed Central

    Nyhan, William L.; Bakay, Bohdan; Connor, James D.; Marks, James F.; Keele, Doman K.

    1970-01-01

    In women heterozygous for hypoxanthine guanine phosphoribosyl trasferase deficiency, the activity of this enzyme in the erythrocyte is usually normal. In a key kindred two such obligate heterozygotes were also heterozygous for glucose-6-phosphate dehydrogenase types A and B. The AB genotype was confirmed in one by assay of skin fibroblasts. Erythrocytes were exclusively of type B. These observations suggest the clonal origin of the hematopoietic system in these women from a primordial cell line with a single active X chromosome. Images PMID:5263751

  9. Single Cell Cytochemistry Illustrated by the Demonstration of Glucose-6-Phosphate Dehydrogenase Deficiency in Erythrocytes.

    PubMed

    Peters, Anna L; van Noorden, Cornelis J F

    2017-01-01

    Cytochemistry is the discipline that is applied to visualize specific molecules in individual cells and has become an essential tool in life sciences. Immunocytochemistry was developed in the sixties of last century and is the most frequently used cytochemical application. However, metabolic mapping is the oldest cytochemical approach to localize activity of specific enzymes, but in the last decades of the previous century and the first decade of the present century it almost became obsolete. The popularity of this approach revived in the past few years. Metabolism gained interest as player in chronic and complex diseases such as cancer, diabetes, neurodegenerative diseases, and vascular diseases and both enzyme cytochemistry and metabolic mapping have become important tools in life sciences.In this chapter, we present glucose-6-phosphate dehydrogenase (G6PD) deficiency, the most prevalent enzyme deficiency worldwide, to illustrate recent developments in enzyme cytochemistry or metabolic mapping. The first assays which were developed quantified enzyme activity but were unreliable for single cell evaluation. The field has expanded with the development of cytochemical single cell assays and DNA testing. Still, all assays-from the earliest developed tests up to the most recently developed tests-have their place in investigations on G6PD activity. Recently, nanoscopy has become available for light and fluorescence microscopy at the nanoscale. For nanoscopy, cytochemistry is an essential tool to visualize intracellular molecular processes. The ultimate goal in the coming years will be nanoscopy of living cells so that the molecular dynamics can be studied. Cytochemistry will undoubtedly play a critical role in these developments.

  10. The effects of chemical and radioactive properties of Tl-201 on human erythrocyte glucose 6-phosphate dehydrogenase activity.

    PubMed

    Sahin, Ali; Senturk, Murat; Ciftci, Mehmet; Varoglu, Erhan; Kufrevioglu, Omer Irfan

    2010-04-01

    The inhibitory effects of thallium-201 ((201)Tl) solution on human erythrocyte glucose 6-phosphate dehydrogenase (G6PD) activity were investigated. For this purpose, erythrocyte G6PD was initially purified 835-fold at a yield of 41.7% using 2',5'-Adenosine diphosphate sepharose 4B affinity gel chromatography. The purification was monitored by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which showed a single band for the final enzyme preparation. The in vitro and in vivo effects of the (201)Tl solution including Tl(+), Fe(+3) and Cu(+2) metals and the in vitro effects of the radiation effect of the (201)Tl solution and non-radioactive Tl(+), Fe(+3) and Cu(+2) metals on human erythrocyte G6PD enzyme were studied. Enzyme activity was determined with the Beutler method at 340 nm using a spectrophotometer. All purification procedures were carried out at +4 degrees C. (201)Tl solution and radiation exposure had inhibitory effects on the enzyme activity. IC(50) value of (201)Tl solution was 36.86 microl ([Tl(+)]: 0.0036 microM, [Cu(+2)]: 0.0116 microM, [Fe(+3)]: 0.0132 microM), of human erythrocytes G6PD. Seven human patients were also used for in vivo studies of (201)Tl solution. Furthermore, non-radioactive Tl(+), Fe(+3) and Cu(+2) were found not to have influenced the enzyme in vitro. Human erythrocyte G6PD activity was inhibited by exposure for up to 10 minutes to 0.057 mCi/kg (201)Tl solution. It was detected in in vitro and in vivo studies that the human erythrocyte G6PD enzyme is inhibited due to the radiation effect of (201)Tl solution. Copyright 2010 Elsevier Inc. All rights reserved.

  11. Canine malignant hyperthermia susceptibility: erythrocytic defects--osmotic fragility, glucose-6-phosphate dehydrogenase deficiency and abnormal Ca2+ homeostasis.

    PubMed Central

    O'Brien, P J; Forsyth, G W; Olexson, D W; Thatte, H S; Addis, P B

    1984-01-01

    Two dogs were diagnosed as malignant hyperthermia susceptible based on increased susceptibility (P less than 0.001) of biopsied muscle to caffeine-induced contracture. Erythrocytes from malignant hyperthermia and normal dogs were then examined for an antioxidant system deficiency. Values for serum muscle enzymes, reticulocytes and corpuscular hemoglobin were mildly elevated. Osmotic fragility was increased: hemolysis occurred at a NaCl concentration 10 mM higher than for normal dogs (P less than 0.001). A 35% glucose-6-phosphate dehydrogenase deficiency (P less than 0.001) with a 40% compensatory increase (P less than 0.01) in 6-phosphogluconate dehydrogenase activity was found. The membrane Ca2+-activated ATPase activity was abnormal: 100% increased with a 40% decreased Arrhenius activation energy (P less than 0.005) and increased thermostability. A 40% increased intracellular accumulation of total Ca2+ occurred in response to in vitro energy depletion in erythrocytes from one malignant hyperthermia dog (P less than 0.01). The multifactorial pattern of inheritance and the broad spectrum of malignant hyperthermia susceptibility are proposed to result from an antioxidant system deficit unmasking or aggravating an intrinsic muscle membrane anomaly. An individual from a family with a history of malignant hyperthermia or unexplained anesthetic death should be considered malignant hyperthermia susceptible if erythrocyte osmotic fragility is abnormal and there is a mild, unexplained elevation in serum creatine kinase. PMID:6150753

  12. A comprehensive analysis of membrane and morphology of erythrocytes from patients with glucose-6-phosphate dehydrogenase deficiency.

    PubMed

    Fang, Zishui; Jiang, Chengrui; Tang, Jia; He, Ming; Lin, Xiaoying; Chen, Xiaodan; Han, Luhao; Zhang, Zhiqiang; Feng, Yi; Guo, Yibin; Li, Hongyi; Jiang, Weiying

    2016-06-01

    Acute hemolytic anemia could be triggered by oxidative stress in the patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. However, the underlying hemolytic mechanism is unknown. To make clear the hemolytic mechanisms, a systematic study on membrane ultrastructure had been undertaken. A comprehensive method was used including atomic force microscopy, scanning electron microscopy, flow cytometer and fluorescence microscopy to analyze the membrane ultrastructure, externalized phosphatidylserine (PS), intracellular Ca(2+) concentration, morphology and the distributions of band 3 protein in G6PD deficient red blood cells (RBCs) after tert-butyl-hydroperoxide (t-BHP) oxidation. The results showed that erythrocyte shrinkage, annexin-V binding to externalized PS on the membrane of early-stage apoptotic cells, the increased membrane roughness and intracellular Ca(2+) concentration, as well as the change of distributions of band 3 protein in RBCs. Compared with the control RBCs, as the concentration of t-BHP up to 0.1mM, the membrane roughness of G6PD deficient RBCs showed significant difference (p<0.05) and as the concentration of t-BHP up to 0.3mM, externalized PS showed significant difference (p<0.05). Furthermore, the population types of RBCs showed dramatic difference between control groups and G6PD deficient groups. Oxidative stress induced more serious erythrocyte apoptosis and resulted in increased roughness of erythrocyte membrane and abnormal distributed band 3 protein in G6PD deficient RBCs. Echinocytes are the predominant abnormal erythrocyte shape occurring in the peripheral blood from patients with G6PD deficiency, which may shorten the RBCs lifespan. The results in the present study will give an increased understanding for the hemolytic mechanism of G6PD deficiency.

  13. [Attempt at characterization of 2 erythrocyte variants of glucose-6-phosphate dehydrogenase in a patient with a partial enzymatic deficit].

    PubMed

    Bansard-Desmidt, N

    1975-09-01

    The electrophoresis shows, in red blood cells of a North African man affected by a glucose-6-phosphate dehydrogenase deficiency, the presence of two enzymes differing by their electrophoretic mobilities: one of them presents in the same mobility as variant Gd (+) B, the other being faster. After partial purification of the enzymes by ionic exchange chromatography on cellex D BIO-RAD, the preparation obtained shows some kinetic abnormalities: an increased value of 2-deoxy-glucose-6-phosphate utilisation and a non linear plot of 1/v versus 1/s, inadequate for Km determination. Assuming that our preparation contains two enzymes differing by their affinities for glucose-6-phosphate, were carried out a study of their Michaelis constants for glucose-6-phosphate by a method based on the densitometric determination of colored spots corresponding to these two variants after electrophoretic separation on cellogel strips. One of these variants is similar to Gd (+) B, the other being characterised by increased values of: electrophoretic mobility (+ 110%), Km for glucose-6-hosphate (194 +/- 38 muM, normal range being 55 to 70 muM), utilisation coefficient of 2-deoxy-glucose-6-phosphate.

  14. Glucose-6-Phosphate Dehydrogenase Revisited

    PubMed Central

    O'Connell, Jerome T.; Henderson, Alfred R.

    1984-01-01

    Hemolytic diseases associated with drugs have been recognized since antiquity. Many of these anemias have been associated with oxidizing agents and deficiencies in the intraerythrocytic enzyme glucose-6-phosphate dehydrogenase. This paper outlines the discovery, prevalence, and variants of this enzyme. Methods of diagnosis of associated anemias are offered. PMID:6502728

  15. Glucose-6-Phosphate Dehydrogenase Deficiency.

    PubMed

    Luzzatto, Lucio; Nannelli, Caterina; Notaro, Rosario

    2016-04-01

    G6PD is a housekeeping gene expressed in all cells. Glucose-6-phosphate dehydrogenase (G6PD) is part of the pentose phosphate pathway, and its main physiologic role is to provide NADPH. G6PD deficiency, one of the commonest inherited enzyme abnormalities in humans, arises through one of many possible mutations, most of which reduce the stability of the enzyme and its level as red cells age. G6PD-deficient persons are mostly asymptomatic, but they can develop severe jaundice during the neonatal period and acute hemolytic anemia when they ingest fava beans or when they are exposed to certain infections or drugs. G6PD deficiency is a global health issue.

  16. Glucose-6-phosphate dehydrogenase deficiency in Chinese

    PubMed Central

    Lai, H. C.; Lai, Michael P. Y.; Leung, Kevin S. N.

    1968-01-01

    In a Chinese population 1,000 full-term male neonates and a further 117 jaundiced neonates of both sexes were studied in an investigation of the frequency of deficiency of erythrocyte glucose-6-phosphate dehydrogenase (G6PD). This enzyme was found to be deficient in 3·6% of male neonates. Correlation of the results with the birthplace of the 602 mothers who were known to come from Kwangtung province showed no significant differences in the frequency of the deficiency between certain parts of the province. The deficiency of G6PD in hemizygous males is profound but it is not associated with erythrocyte acid monophosphoesterase deficiency in Chinese in Hong Kong. The G6PD deficiency accounts for 15·4% of all the 117 cases of neonatal jaundice. The relative importance of G6PD deficiency as a cause of neonatal jaundice does not differ materially in male and female mutants. Neonatal jaundice can occur in all genotypes of G6PD mutation in Chinese. PMID:5697334

  17. [Glucose-6-phosphate dehydrogenase deficiency in Japan].

    PubMed

    Kanno, Hitoshi; Ogura, Hiromi

    2015-07-01

    In the past 10 years, we have diagnosed congenital hemolytic anemia in 294 patients, approximately 33% of whom were found to have glucose-6-phosphate dehydrogenase (G6PD) deficiency. It is becoming more common for Japanese to marry people of other ethnic origins, such that G6PD deficiency is becoming more prevalent in Japan. Japanese G6PD deficiency tends to be diagnosed in the neonatal period due to severe jaundice, while G6PD-deficient patients with foreign ancestors tend to be diagnosed at the onset of an acute hemolytic crisis before the age of six. It is difficult to predict the clinical course of each patient by G6PD activity, reduced glutathione content, or the presence/absence of severe neonatal jaundice. We propose that both neonatal G6PD screening and systematic analyses of G6PD gene mutations may be useful for personalized management of patients with G6PD-deficient hemolytic anemia.

  18. Producing Glucose 6-Phosphate from Cellulosic Biomass

    PubMed Central

    Bacik, John-Paul; Klesmith, Justin R.; Whitehead, Timothy A.; Jarboe, Laura R.; Unkefer, Clifford J.; Mark, Brian L.; Michalczyk, Ryszard

    2015-01-01

    The most abundant carbohydrate product of cellulosic biomass pyrolysis is the anhydrosugar levoglucosan (1,6-anhydro-β-d-glucopyranose), which can be converted to glucose 6-phosphate by levoglucosan kinase (LGK). In addition to the canonical kinase phosphotransfer reaction, the conversion requires cleavage of the 1,6-anhydro ring to allow ATP-dependent phosphorylation of the sugar O6 atom. Using x-ray crystallography, we show that LGK binds two magnesium ions in the active site that are additionally coordinated with the nucleotide and water molecules to result in ideal octahedral coordination. To further verify the metal binding sites, we co-crystallized LGK in the presence of manganese instead of magnesium and solved the structure de novo using the anomalous signal from four manganese atoms in the dimeric structure. The first metal is required for catalysis, whereas our work suggests that the second is either required or significantly promotes the catalytic rate. Although the enzyme binds its sugar substrate in a similar orientation to the structurally related 1,6-anhydro-N-acetylmuramic acid kinase (AnmK), it forms markedly fewer bonding interactions with the substrate. In this orientation, the sugar is in an optimal position to couple phosphorylation with ring cleavage. We also observed a second alternate binding orientation for levoglucosan, and in these structures, ADP was found to bind with lower affinity. These combined observations provide an explanation for the high Km of LGK for levoglucosan. Greater knowledge of the factors that contribute to the catalytic efficiency of LGK can be used to improve applications of this enzyme for levoglucosan-derived biofuel production. PMID:26354439

  19. Inhibitory effect of a fava bean component on the in vitro development of Plasmodium falciparum in normal and glucose-6-phosphate dehydrogenase deficient erythrocytes.

    PubMed

    Golenser, J; Miller, J; Spira, D T; Navok, T; Chevion, M

    1983-03-01

    We examined the hypothesis that G-6-PD deficiency associated with fava bean ingestion confers resistance to malaria by studying the in vitro interactions between malaria parasites (Plasmodium falciparum), human erythrocytes with varying degrees of G-6-PD deficiency, and isouramil (IU), a fava bean extract that is known to cause oxidant stress and hemolysis of G-6-PD-deficient erythrocytes. Untreated G-6-PD-deficient and normal erythrocytes supported the in vitro growth of P. falciparum equally well. However, after pretreatment with IU, G-6-PD-deficient erythrocytes did not support parasite growth in vitro, whereas growth remained high in normal erythrocytes. Parasite growth was proportional to the G-6-PD activity of the IU-treated erythrocytes. In contrast, when parasitized erythrocytes were exposed to IU, parasites even in normal erythrocytes were destroyed. Ring forms were much less sensitive than late trophozoites and schizonts. The results suggest that there are two modes by which IU affects the development of P. falciparum and demonstrate in vitro that G-6-PD deficiency confers resistance against malaria under conditions of fava-bean-associated oxidant stress.

  20. Priapism and glucose-6-phosphate dehydrogenase deficiency: An underestimated correlation?

    PubMed

    De Rose, Aldo Franco; Mantica, Guglielmo; Tosi, Mattia; Bovio, Giulio; Terrone, Carlo

    2016-10-05

    Priapism is a rare clinical condition characterized by a persistent erection unrelated to sexual excitement. Often the etiology is idiopathic. Three cases of priapism in glucose-6-phosphate dehydrogenase (G6PD) deficiency patients have been described in literature. We present the case of a 39-year-old man with glucose- 6-phosphate dehydrogenase deficiency, who reached out to our department for the arising of a non-ischemic priapism without arteriolacunar fistula. We suggest that the glucose-6-phosphate dehydrogenase deficiency could be an underestimated risk factor for priapism.

  1. Structural basis for glucose-6-phosphate activation of glycogen synthase

    SciTech Connect

    Baskaran, Sulochanadevi; Roach, Peter J.; DePaoli-Roach, Anna A.; Hurley, Thomas D.

    2010-11-22

    Regulation of the storage of glycogen, one of the major energy reserves, is of utmost metabolic importance. In eukaryotes, this regulation is accomplished through glucose-6-phosphate levels and protein phosphorylation. Glycogen synthase homologs in bacteria and archaea lack regulation, while the eukaryotic enzymes are inhibited by protein kinase mediated phosphorylation and activated by protein phosphatases and glucose-6-phosphate binding. We determined the crystal structures corresponding to the basal activity state and glucose-6-phosphate activated state of yeast glycogen synthase-2. The enzyme is assembled into an unusual tetramer by an insertion unique to the eukaryotic enzymes, and this subunit interface is rearranged by the binding of glucose-6-phosphate, which frees the active site cleft and facilitates catalysis. Using both mutagenesis and intein-mediated phospho-peptide ligation experiments, we demonstrate that the enzyme's response to glucose-6-phosphate is controlled by Arg583 and Arg587, while four additional arginine residues present within the same regulatory helix regulate the response to phosphorylation.

  2. Glucose-6-phosphate dehydrogenase deficiency: the added value of cytology.

    PubMed

    Roelens, Marie; Dossier, Claire; Fenneteau, Odile; Couque, Nathalie; Da Costa, Lydie

    2016-06-01

    We report the case of a 2 year-old boy hospitalized into the emergency room for influenza pneumonia infection. The evolution was marked by a respiratory distress syndrome, a severe hemolytic anemia, associated with thrombocytopenia and kidney failure. First, a diagnosis of hemolytic uremic syndrome (HUS) has been judiciously suggested due to the classical triad: kidney failure, hemolytic anemia and thrombocytopenia. But, strikingly, blood smears do not exhibit schizocytes, but instead ghosts and hemighosts, some characteristic features of a glucose-6-phosphate dehydrogenase deficiency. Our hypothesis has been confirmed by enzymatic dosage and molecular biology. The unusual initial aplastic feature of this anemia could be the result of a transient erythroblastopenia due to the viral agent, at the origin of the G6PD crisis on a background of a major erythrocyte anti-oxydant enzyme defect. This case of G6PD defect points out the continuously importance of the cytology, which was able to redirect the diagnosis by the hemighost and ghost detection.

  3. Red Algal Bromophenols as Glucose 6-Phosphate Dehydrogenase Inhibitors

    PubMed Central

    Mikami, Daisuke; Kurihara, Hideyuki; Kim, Sang Moo; Takahashi, Koretaro

    2013-01-01

    Five bromophenols isolated from three Rhodomelaceae algae (Laurencia nipponica, Polysiphonia morrowii, Odonthalia corymbifera) showed inhibitory effects against glucose 6-phosphate dehydrogenase (G6PD). Among them, the symmetric bromophenol dimer (5) showed the highest inhibitory activity against G6PD. PMID:24152564

  4. Glucose-6-phosphate dehydrogenase deficiency: not exclusively in males.

    PubMed

    van den Broek, Leonie; Heylen, Evelien; van den Akker, Machiel

    2016-12-01

    Glucose-6-phosphate (G6PD) deficiency is the most common human enzyme defect, often presenting with neonatal jaundice and/or acute hemolytic anemia, triggered by oxidizing agents. G6PD deficiency is an X-linked, hereditary disease, mainly affecting men, but should also be considered in females with an oxidative hemolysis.

  5. In vivo lability of glucose-6-phosphate dehydrogenase in GdA- and Gdmediterranean deficiency

    PubMed Central

    Piomelli, Sergio; Corash, Laurence M.; Davenport, Deatra D.; Miraglia, Janet; Amorosi, Edward L.

    1968-01-01

    A decreased level of glucose-6-phosphate dehydrogenase might result from decreased rate of synthesis, synthesis of an enzyme of lower catalytic efficiency, increased lability, or a combined mechanism. To test the hypothesis of increased lability, the rate of decline of the enzyme in vivo was measured in three groups of individuals, controls, Gd(—),A-males, and Gd(—), Mediterranean males, by the slope of decline of activity in fractions containing erythrocytes of progressively increasing mean age. These fractions were obtained by ultracentrifugation on a discontinuous density gradient of erythrocyte suspensions free of contaminating platelets and leukocytes. The rate of in vivo decline of pyruvate kinase (another age-dependent enzyme) was also measured and found very similar in the three groups. The in vivo decline of glucose-6-phosphate dehydrogenase was found to follow an exponential rate, with a half-life of 62 days for controls and 13 days for Gd(—),A- erythrocytes. The activity in normal reticulocytes was estimated at 9.7 U and in Gd(—),A- reticulocytes at 8.8 U. These estimates were confirmed by direct measurements in reticulocytes isolated from patients with extreme reticulocytosis. In Gd(—),Mediterranean erythrocytes activity could be demonstrated only in reticulocytes, which were estimated to average 1.4 U. The rate of decline is so extreme that no activity could be detected in mature erythrocytes. These data suggest that the glucose-6-phosphate dehydrogenase deficiency of both the GdA- and the GdMediterranean variant results from different degrees of in vivo instability of the abnormal enzyme. PMID:5641629

  6. The glucose-6-phosphate transport is not mediated by a glucose-6-phosphate/phosphate exchange in liver microsomes.

    PubMed

    Marcolongo, Paola; Fulceri, Rosella; Giunti, Roberta; Margittai, Eva; Banhegyi, Gabor; Benedetti, Angelo

    2012-09-21

    A phosphate-linked antiporter activity of the glucose-6-phosphate transporter (G6PT) has been recently described in liposomes including the reconstituded transporter protein. We directly investigated the mechanism of glucose-6-phosphate (G6P) transport in rat liver microsomal vesicles. Pre-loading with inorganic phosphate (Pi) did not stimulate G6P or Pi microsomal inward transport. Pi efflux from pre-loaded microsomes could not be enhanced by G6P or Pi addition. Rapid G6P or Pi influx was registered by light-scattering in microsomes not containing G6P or Pi. The G6PT inhibitor, S3483, blocked G6P transport irrespectively of experimental conditions. We conclude that hepatic G6PT functions as an uniporter.

  7. [Hemoglobin Woodville associated with double point mutation in the gene of glucose-6-phosphate dehydrogenase].

    PubMed

    Mansini, Adrián P; Fernández, Diego A; Aguirre, Fernando M; Pepe, Carolina; Milanesio, Berenice; Chaves, Alejandro; Eandi Eberle, Silvia; Feliú Torres, Aurora

    2015-01-01

    The co-inheritance of erythrocyte defects, hemoglobinopathies, enzymopathies, and membranopathies is not an unusual event. For the diagnosis, a laboratory strategy, including screening and confirmatory tests, additional to molecular characterization, was designed. As the result of this approach, a 24-year-old man carrying a hemoglobinopathy (Hemoglobin Woodville) and an enzymopathy (glucose-6-phosphate dehydrogenase deficiency) was identified. In the heterozygous state hemoglobin Woodville, is asymptomatic, and homozygous or double heterozygous individuals have not been reported thus far. On the other hand, previously described double point mutation in the gene for glucose-6-phosphate dehydrogenase c. [202G>A; 376A>G], p. [Val 68Met; Asn126Asp], causes hemolysis of varying severity after food or drug intake or infections. This case highlights the importance of the methodology carried out for the diagnosis, treatment, and proper genetic counseling.

  8. Malaria, favism and glucose-6-phosphate dehydrogenase deficiency.

    PubMed

    Huheey, J E; Martin, D L

    1975-10-15

    Although glucose-6-phosphate dehydrogenase deficient individuals may suffer (sometimes fatally) from favism, a high incidence of this trait occurs in many Mediterranean populations. This apparent paradox is explained on the basis of a synergistic interaction between favism and G-6-PD deficiency that provides increased protection against malaria compared to that of the G-6-PD deficiency alone. This relationship is analogous to that between various hemoglobins and malaria in that there is selection for a more severe trait if it provides more protection against malaria.

  9. Drug-induced haemolysis in glucose-6-phosphate dehydrogenase deficiency.

    PubMed Central

    Chan, T K; Todd, D; Tso, S C

    1976-01-01

    People with the variants of glucose-6-phosphate dehydrogenase (GPD) deficiency common in the southern Chinese (Canton, B(-)Chinese, and Hong Kong-Pokfulam) have a moderate shortening of red-cell survival but no anaemia when they are in the steady state. With a cross-transfusion technique, primaquine, nitrofurantoin, and large doses of aspirin were found to aggravate the haemolysis while sulphamethoxazole did so only in some people. Individual differences in drug metabolism may be the reason for this. Many commonly used drugs reported to accentuate haemolysis in GPD deficiency did not shorten red-cell survival. PMID:990860

  10. Inhibition of hexose transport by glucose in a glucose-6-phosphate isomerase mutant of Saccharomyces cerevisiae.

    PubMed

    Alonso, A; Pascual, C; Romay, C; Herrera, L; Kotyk, A

    1989-01-01

    The rate of hexose transport was approximately 60% lower for both the high- and the low-affinity components of hexose uptake when a glucose-6-phosphate isomerase mutant of Saccharomyces cerevisiae was preincubated with glucose, as compared with preincubation with water. Similarly the Jmax value of the high-affinity system of the mutant was 25-35% of the corresponding Jmax value for normal cells incubated with glucose. Accumulation of glucose 6-phosphate or of some other metabolite, such as fructose 6-phosphate or trehalose, may be responsible for this striking inhibition.

  11. Astrocytic glucose-6-phosphatase and the permeability of brain microsomes to glucose 6-phosphate.

    PubMed Central

    Forsyth, R J; Bartlett, K; Burchell, A; Scott, H M; Eyre, J A

    1993-01-01

    Cells from primary rat astrocyte cultures express a 36.5 kDa protein that cross-reacts with polyclonal antibodies to the catalytic subunit of rat hepatic glucose-6-phosphatase on Western blotting. Glucose-6-phosphate-hydrolysing activity of the order of 10 nmol/min per mg of total cellular protein can be demonstrated in cell homogenates. This activity shows latency, and is localized to the microsomal fraction. Kinetic analysis shows a Km of 15 mM and a Vmax. of 30 nmol/min per mg of microsomal protein in disrupted microsomes. Approx. 40% of the total phosphohydrolase activity is specific glucose-6-phosphatase, as judged by sensitivity to exposure to pH 5 at 37 degrees C. Previous reports that the brain microsomal glucose-6-phosphatase system does not distinguish glucose 6-phosphate and mannose 6-phosphate are confirmed in astrocyte microsomes. However, we demonstrate significant phosphomannose isomerase activity in brain microsomes, allowing for ready interconversion between mannose 6-phosphate and glucose 6-phosphate (Vmax. 15 nmol/min per mg of microsomal protein; apparent Km < 1 mM; pH optimum 5-6 for the two-step conversion). This finding invalidates the past inference from the failure of brain microsomes to distinguish mannose 6-phosphate and glucose 6-phosphate that the cerebral glucose-6-phosphatase system lacks a 'glucose 6-phosphate translocase' [Fishman and Karnovsky (1986) J. Neurochem. 46, 371-378]. Furthermore, light-scattering experiments confirm that a proportion of whole brain microsomes is readily permeable to glucose 6-phosphate. Images Figure 1 PMID:8395816

  12. Is glucose-6-phosphate dehydrogenase deficiency more prevalent in Carrion's disease endemic areas in Latin America?

    PubMed

    Mazulis, Fernando; Weilg, Claudia; Alva-Urcia, Carlos; Pons, Maria J; Del Valle Mendoza, Juana

    2015-12-01

    Glucose-6-phosphate dehydrogenase (G6PD) is a cytoplasmic enzyme with an important function in cell oxidative damage prevention. Erythrocytes have a predisposition towards oxidized environments due to their lack of mitochondria, giving G6PD a major role in its stability. G6PD deficiency (G6PDd) is the most common enzyme deficiency in humans; it affects approximately 400 million individuals worldwide. The overall G6PDd allele frequency across malaria endemic countries is estimated to be 8%, corresponding to approximately 220 million males and 133 million females. However, there are no reports on the prevalence of G6PDd in Andean communities where bartonellosis is prevalent.

  13. Hemolytic anemia caused by glucose-6-phosphate dehydrogenase deficiency.

    PubMed

    Olivares, N; Medina, C; Sánchez-Corona, J; Rivas, F; Rivera, H; Hernández, A; Delgado, J L; Ibarra, B; Cantú, J M; Vaca, G; Martínez, C

    1979-01-01

    Results are reported concerning quantitation of glucose -6- phosphate dehydrogenase (G6PD) enzyme activity where in one of the members of a family a clinical diagnosis of acute hemolytic anemia due to G6PD deficiency had been established. In the propositus, G6PD levels were found to be less than 10 per cent thus confirming diagnosis; the same enzymatic deficiency was identified in one of the siblings without a history of hematologic pathology and in a maternal cousin with a history of neonatal jaundice as well as two obliged carriers. Electrophoretical enzyme phenotype was similar to A variant in three affected males. Advantages of prevention and medical care possible with early diagnosis of G6PD deficiency are discussed.

  14. Conjugated bilirubin in neonates with glucose-6-phosphate dehydrogenase deficiency.

    PubMed

    Kaplan, M; Rubaltelli, F F; Hammerman, C; Vilei, M T; Leiter, C; Abramov, A; Muraca, M

    1996-05-01

    We used a system capable of measuring conjugated bilirubin and its monoconjugated and diconjugated fractions in serum to assess bilirubin conjugation in 29 glucose-6-phosphate dehydrogenase (G6PD)-deficient, term, male newborn infants and 35 control subjects; all had serum bilirubin levels > or = 256 mumol/L (15 mg/dI). The median value for diconjugated bilirubin was lower in the G6PD-deficient neonates than in control subjects (0.06 (range 0.00 to 1.84) vs 0.21 (range 0.00 to 1.02) mumol/L, p = 0.006). Diglucuronide was undetectable in 11 (38.9%) of the G6PD-deficient infants versus 3 (8.6%) of the control subjects (p = 0.015). These findings imply a partial defect of bilirubin conjugation not previously demonstrated in G6PD-deficient newborn infants.

  15. Psychotic mania in glucose-6-phosphate-dehydrogenase-deficient subjects

    PubMed Central

    Bocchetta, Alberto

    2003-01-01

    Background Glucose-6-phosphate dehydrogenase (G6PD) deficiency has been associated with acute psychosis, catatonic schizophrenia, and bipolar disorders by previous inconclusive reports. A particularly disproportionate rate of enzyme deficiency was found in manic schizoaffective patients from 662 lithium patients surveyed in Sardinia. The purpose of this study was to describe clinical characteristics which may be potentially associated with G6PD deficiency. Methods Characteristics of episodes, course of illness, family pattern of illness, laboratory tests, and treatment response of 29 G6PD-deficient subjects with a Research Diagnostic Criteria diagnosis of manic schizoaffective disorder were abstracted from available records. Results The most peculiar pattern was that of acute recurrent psychotic manic episodes, mostly characterized by loosening of associations, agitation, catatonic symptoms, and/or transient confusion, concurrent hyperbilirubinemia, positive psychiatric family history, and partial response to long-term lithium treatment. Conclusions A relationship between psychiatric disorder and G6PD deficiency is to be searched in the bipolar spectrum, particularly among patients with a history of acute episodes with psychotic and/or catatonic symptoms or with transient confusion. PMID:12844366

  16. Inactivation of Bakers' yeast glucose-6-phosphate dehydrogenase by aluminum

    SciTech Connect

    Cho, Sungwoo; Joshi, J.G. )

    1989-04-18

    Preincubation of yeast glucose-6-phosphate dehydrogenase (G6PD) with Al(III) produced an inactive enzyme containing 1 mol of Al(III)/mol of enzyme subunit. None of the enzyme-bound Al(III) was dissociated by dialysis against 10 mM Tris-HCl, pH 7.0, containing 0.2 mM EDTA at 4{degree}C for 24 h. Citrate, NADP{sup +}, EDTA, or NaF protected the enzyme against the Al(III) inactivation. The Al(III)-inactivated enzyme, however, was completely reactivated only by citrate and NaF. The dissociation constant for the enzyme-aluminum complex was calculated to be 4 {times} 10{sup {minus}6} M with NaF, a known reversible chelator for aluminum. Modification of histidine and lysine residues of the enzyme with diethyl pyrocarbonate and acetylsalicylic acid, respectively, inactivated the enzyme. However, the modified enzyme still bound 1 mol of Al(III)/mol of enzyme subunit. Circular dichroism studies showed that the binding of Al(III) to the enzyme induced a decrease in {alpha}-helix and {beta}-sheet and an increase in random coil. Therefore, it is suggested that inactivation of G6PD by Al(III) is due to the conformational change induced by Al(III) binding.

  17. Glutathion peroxidase and glucose-6-phosphate dehydrogenase activities in bovine blood and liver.

    PubMed

    Abd Ellah, Mahmoud Rushdi; Niishimori, Kazuhiro; Goryo, Masanobu; Okada, Keiji; Yasuda, Jun

    2004-10-01

    A total of 46 cattle, including 25 as control, 16 with glycogen degeneration and 5 with severe fatty degeneration were studied. Whole blood and liver tissue specimens were used to measure glutathione peroxidase (GSH-Px) and Glucose-6-Phosphate Dehydrogenase (G6PD) activities. The present study determined the value of these parameters in diagnosing glycogen and fatty degeneration in cattle from the point of the status of antioxidation and lipid peroxidation. The results showed a significant decrease in hepatic GSH-Px activity and a significant increase in hepatic G6PD activity in cases of fatty degeneration. On the other hand, there were no significant changes in erythrocytic and hepatic GSH-Px and G6PD activities in cases of glycogen degeneration. The results indicated lipoperoxidation process in the liver tissues increased in cases of fatty degeneration. Therefore, supplying animals suffering from fatty liver with sufficient quantities of nutrient antioxidants may be valuable when treatment is considered.

  18. Diagnostic value of glucose-6-phosphate isomerase in rheumatoid arthritis.

    PubMed

    Fan, Lie Ying; Zong, Ming; Wang, Qiang; Yang, Lin; Sun, Li Shan; Ye, Qin; Ding, Yuan Yuan; Ma, Jian Wei

    2010-12-14

    Although glucose-6-phosphate isomerase (G6PI), anti-G6PI antibodies and G6PI-containing immune complexes (G6PI-CIC) have proved high expression in patients with rheumatoid arthritis (RA), comprehensive evaluation of the G6PI-derived markers, G6PI antigen, anti-G6PI Abs, G6PI-CIC and G6PI mRNA, in the diagnosis of RA remains necessary. We measured G6PI antigen, anti-G6PI Abs, C1q/G6PI-CIC as well as anti-cyclic citrullinated peptide antibodies (anti-CCP Abs) in serum and concomitantly synovial fluid (SF) by ELISA in RA, other rheumatic diseases and healthy controls. The G6PI mRNA expression in peripheral blood mononuclear cells (PBMCs) was assessed with real-time PCR. As compared with non-RA patients, RA patients had increased levels of G6PI antigen, anti-G6PI Abs, C1q/G6PI-CIC and G6PI mRNA expression in sera or PBMCs, and increased levels of G6PI and C1q/G6PI-CIC in SF. The serum G6PI levels in RA patients positively correlated with anti-G6PI Abs, C1q/G6PI-CIC, G6PI mRNA, anti-CCP Abs, RF, CRP and ESR, respectively. The area under curve analyses demonstrated that serum G6PI had the best discriminating power for RA and active RA followed by C1q/G6PI-CIC, anti-G6PI Abs and G6PI mRNA. The simultaneous use of serum G6PI and anti-CCP Abs assays in the form of either of them tested positive gave improved sensitivities of 88.1% for RA and 95.8% for active RA. Despite the elevated expression of all G6PI-derived markers in RA, the serum G6PI has the best discriminating power among the four G6PI-derived markers. The serum G6PI determination either alone or in combination with anti-CCP Abs improves the diagnosis of RA. Copyright © 2010 Elsevier B.V. All rights reserved.

  19. Glucose-6-phosphate dehydrogenase deficiency in Nigerian children.

    PubMed

    Williams, Olatundun; Gbadero, Daniel; Edowhorhu, Grace; Brearley, Ann; Slusher, Tina; Lund, Troy C

    2013-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzymopathy and in Sub-Saharan Africa, is a significant cause of infection- and drug-induced hemolysis and neonatal jaundice. Our goals were to determine the prevalence of G6PD deficiency among Nigerian children of different ethnic backgrounds and to identify predictors of G6PD deficiency by analyzing vital signs and hematocrit and by asking screening questions about symptoms of hemolysis. We studied 1,122 children (561 males and 561 females) aged 1 month to 15 years. The mean age was 7.4 ± 3.2 years. Children of Yoruba ethnicity made up the largest group (77.5%) followed by those Igbo descent (10.6%) and those of Igede (10.2%) and Tiv (1.8%) ethnicity. G6PD status was determined using the fluorescent spot method. We found that the overall prevalence of G6PD deficiency was 15.3% (24.1% in males, 6.6% in females). Yoruba children had a higher prevalence (16.9%) than Igede (10.5%), Igbo (10.1%) and Tiv (5.0%) children. The odds of G6PD deficiency were 0.38 times as high in Igbo children compared to Yoruba children (p=0.0500). The odds for Igede and Tiv children were not significantly different from Yoruba children (p=0.7528 and 0.9789 respectively). Mean oxygen saturation, heart rate and hematocrit were not significantly different in G6PD deficient and G6PD sufficient children. The odds of being G6PD deficient were 2.1 times higher in children with scleral icterus than those without (p=0.0351). In conclusion, we determined the prevalence of G6PD deficiency in Nigerian sub-populations. The odds of G6PD deficiency were decreased in Igbo children compared to Yoruba children. There was no association between vital parameters or hematocrit and G6PD deficiency. We found that a history of scleral icterus may increase the odds of G6PD deficiency, but we did not exclude other common causes of icterus such as sickle cell disease or malarial infection.

  20. Mimicked translocation of glucose and glucose 6-phosphate with artificial enzyme membranes.

    PubMed Central

    Maïsterrena, B; Coulet, P R

    1989-01-01

    An approach to the mechanism which may govern the behaviour of biological compartmentalized systems is presented. Artificial enzyme membranes with immobilized glucose oxidase, invertase or hexokinase were used to separate two compartments of a specially designed diffusion cell. Asymmetry in volume, hydrodynamic conditions and enzyme location was purposely chosen in order to create situations which could not be obtained with an enzyme free in solution, and was then used to tentatively mimic situations existing in vivo. Experiments were conducted and a translocation effect of H2O2, glucose and glucose 6-phosphate was obtained. A theoretical analysis taking into account the different identified parameters of the system was elaborated. PMID:2764883

  1. A case of ataxia telangiectasia with unbalanced glucose 6-phosphate dehydrogenase mosaicism in the granulocytic/monocytic lineages.

    PubMed Central

    Ferraris, A M; Melani, C; Canepa, L; Meloni, T; Forteleoni, G; Gaetani, G F

    1987-01-01

    Ataxia telangiectasia is a genetically determined disease with multi-system abnormalities and a high incidence of neoplasia. In order to define the nature of the association between ataxia telangiectasia and malignancy, we investigated a patient with the disease and heterozygote for the Mediterranean variant of the X-linked marker glucose 6-phosphate dehydrogenase. Enzymatic mosaicism in hemopoietic and nonhemopoietic cells was evaluated with the 2-deoxy glucose 6-phosphate technique. While erythrocytes, platelets, and lymphocytes expressed the same double-enzyme phenotype as tissues of nonhemopoietic origin, granulocytes and monocytes expressed almost exclusively the Mediterranean-type enzyme. We suggest that, as the result of genetic instability at the hemopoietic stem-cell level, the granulocytic/monocytic progeny enjoyed a proliferative advantage and became the predominant clone. PMID:3812485

  2. Glucose-6-phosphate dehydrogenase deficiency presented with convulsion: a rare case.

    PubMed

    Merdin, Alparslan; Avci, Fatma; Guzelay, Nihal

    2014-01-29

    Red blood cells carry oxygen in the body and Glucose-6-Phosphate Dehydrogenase protects these cells from oxidative chemicals. If there is a lack of Glucose-6-Phosphate Dehydrogenase, red blood cells can go acute hemolysis. Convulsion is a rare presentation for acute hemolysis due to Glucose-6-Phosphate Dehydrogenase deficiency. Herein, we report a case report of a Glucose-6-Phosphate Dehydrogenase deficiency diagnosed patient after presentation with convulsion. A 70 year-old woman patient had been hospitalized because of convulsion and fatigue. She has not had similar symptoms before. She had ingested fava beans in the last two days. Her hypophyseal and brain magnetic resonance imaging were normal. Blood transfusion was performed and the patient recovered.

  3. Dental Considerations in Children with Glucose-6-phosphate Dehydrogenase Deficiency (Favism): A Review of the Literature and Case Report.

    PubMed

    Hernández-Pérez, Daniela; Butrón-Téllez Girón, Claudia; Ruiz-Rodríguez, Socorro; Garrocho-Rangel, Arturo; Pozos-Guillén, Amaury

    2015-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an uncommon inherited enzyme deficiency characterized by hemolytic anemia, caused by the inability of erythrocytes to detoxify oxidizing agents such as drugs, infectious diseases, or fava bean ingestion. In this later case, the disorder is known as favism. The aim of the present report was to present a review of the literature in this disease, to describe a case report concerning an affected 9-year-old male, and to review the main implications and precautions in pediatric dental management.

  4. Dental Considerations in Children with Glucose-6-phosphate Dehydrogenase Deficiency (Favism): A Review of the Literature and Case Report

    PubMed Central

    Hernández-Pérez, Daniela; Butrón-Téllez Girón, Claudia; Ruiz-Rodríguez, Socorro; Garrocho-Rangel, Arturo; Pozos-Guillén, Amaury

    2015-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an uncommon inherited enzyme deficiency characterized by hemolytic anemia, caused by the inability of erythrocytes to detoxify oxidizing agents such as drugs, infectious diseases, or fava bean ingestion. In this later case, the disorder is known as favism. The aim of the present report was to present a review of the literature in this disease, to describe a case report concerning an affected 9-year-old male, and to review the main implications and precautions in pediatric dental management. PMID:26435857

  5. Glucose-6-phosphate dehydrogenase and red cell pyruvate kinase deficiency in neonatal jaundice cases in egypt.

    PubMed

    Abdel Fattah, Mohammed; Abdel Ghany, Eman; Adel, Alia; Mosallam, Dalia; Kamal, Shahira

    2010-05-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency can lead to acute hemolytic anemia, chronic nonspherocytic hemolytic anemia, and neonatal jaundice. Neonatal red cell pyruvate kinase (PK) deficiency may cause clinical patterns, ranging from extremely severe hemolytic anemia to moderate jaundice. The authors aimed at studying the prevalence of G6PD and PK deficiency among Egyptian neonates with pathological indirect hyperbilirubinemia in Cairo. This case-series study included 69 newborns with unconjugated hyperbilirubinemia. All were subjected to clinical history, laboratory investigations, e.g., complete blood counts, reticulocytic counts, direct and indirect serum bilirubin levels, Coombs tests, qualitative assay of G6PD activity by methemoglobin reduction test, and measurement of erythrocytic PK levels. The study detected 10 neonates with G6PD deficiency, which means that the prevalence of G6PD deficiency among Egyptian neonates with hyperbilirubinemia is 14.4% (21.2% of males). G6PD deficiency was significantly higher in males than females (P = .01). The authors detected 2 cases with PK deficiency, making the prevalence of its deficiency 2.8%. These data demonstrate that G6PD deficiency is an important cause for neonatal jaundice in Egyptians. Neonatal screening for its deficiency is recommended. PK deficiency is not a common cause of neonatal jaundice. However, this needs further investigation on a larger scale.

  6. Hereditary sideroblastic anemia and glucose-6-phosphate dehydrogenase deficiency in a Negro family.

    PubMed

    Prasad, A S; Tranchida, L; Konno, E T; Berman, L; Albert, S; Sing, C F; Brewer, G J

    1968-06-01

    Detailed clinical and genetic studies have been performed in a Negro family, which segregated for sex-linked sideroblastic anemia and glucose-6-phosphate dehydrogenase (G-6-DP) deficiency. This is the first such pedigree reported. Males affected with sideroblastic anemia had growth retardation, hypochromic microcytic anemia, elevated serum iron, decreased unsaturated iron-binding capacity, increased (59)Fe clearance, low (59)Fe incorporation into erythrocytes, normal erythrocyte survival ((51)Cr), normal hemoglobin electrophoretic pattern, erythroblastic hyperplasia of marrow with increased iron, and marked increase in marrow sideroblasts, particularly ringed sideroblasts. Perinuclear deposition of ferric aggregates was demonstrated to be intramitochondrial by electron microscopy. Female carriers of the sideroblastic gene were normal but exhibited a dimorphic population of erythrocytes including normocytic and microcytic cells. The bone marrow studies in the female (mother) showed ringed marrow sideroblasts. Studies of G-6-PD involved the methemoglobin elution test for G-6-PD activity of individual erythrocytes, quantitative G-6-PD assay, and electrophoresis. In the pedigree, linkage information was obtained from a doubly heterozygous woman, four of her sons, and five of her daughters. Three sons were doubly affected, and one was normal. One daughter appeared to be a recombinant. The genes appeared to be linked in the coupling phase in the mother. The maximum likelihood estimate of the recombination value was 0.14. By means of Price-Jones curves, the microcytic red cells in peripheral blood were quantitated in female carriers. The sideroblast count in the bone marrow in the mother corresponded closely to the percentage of microcytic cells in peripheral blood. This is the second example in which the cellular expression of a sex-linked trait has been documented in the human red cells, the first one being G-6-PD deficiency. The coexistence of the two genes in doubly

  7. Antimalarial NADPH-Consuming Redox-Cyclers As Superior Glucose-6-Phosphate Dehydrogenase Deficiency Copycats

    PubMed Central

    Bielitza, Max; Belorgey, Didier; Ehrhardt, Katharina; Johann, Laure; Lanfranchi, Don Antoine; Gallo, Valentina; Schwarzer, Evelin; Mohring, Franziska; Jortzik, Esther; Williams, David L.; Becker, Katja; Arese, Paolo; Elhabiri, Mourad

    2015-01-01

    Abstract Aims: Early phagocytosis of glucose-6-phosphate dehydrogenase (G6PD)-deficient erythrocytes parasitized by Plasmodium falciparum were shown to protect G6PD-deficient populations from severe malaria. Here, we investigated the mechanism of a novel antimalarial series, namely 3-[substituted-benzyl]-menadiones, to understand whether these NADPH-consuming redox-cyclers, which induce oxidative stress, mimic the natural protection of G6PD deficiency. Results: We demonstrated that the key benzoylmenadione metabolite of the lead compound acts as an efficient redox-cycler in NADPH-dependent methaemoglobin reduction, leading to the continuous formation of reactive oxygen species, ferrylhaemoglobin, and subsequent haemichrome precipitation. Structure–activity relationships evidenced that both drug metabolites and haemoglobin catabolites contribute to potentiate drug effects and inhibit parasite development. Disruption of redox homeostasis by the lead benzylmenadione was specifically induced in Plasmodium falciparum parasitized erythrocytes and not in non-infected cells, and was visualized via changes in the glutathione redox potential of living parasite cytosols. Furthermore, the redox-cycler shows additive and synergistic effects in combination with compounds affecting the NADPH flux in vivo. Innovation: The lead benzylmenadione 1c is the first example of a novel redox-active agent that mimics the behavior of a falciparum parasite developing inside a G6PD-deficient red blood cell (RBC) giving rise to malaria protection, and it exerts specific additive effects that are inhibitory to parasite development, without harm for non-infected G6PD-sufficient or -deficient RBCs. Conclusion: This strategy offers an innovative perspective for the development of future antimalarial drugs for G6PD-sufficient and -deficient populations. Antioxid. Redox Signal. 22, 1337–1351. PMID:25714942

  8. Cryopreservation of glucose-6-phosphate dehydrogenase activity inside red blood cells: developing a specimen repository in support of development and evaluation of glucose-6-phosphate dehydrogenase deficiency tests.

    PubMed

    Kahn, Maria; LaRue, Nicole; Bansil, Pooja; Kalnoky, Michael; McGray, Sarah; Domingo, Gonzalo J

    2013-08-20

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common human enzyme deficiency. It is characterized by abnormally low levels of G6PD activity. Individuals with G6PD deficiency are at risk of undergoing acute haemolysis when exposed to 8‒aminoquinoline-based drugs, such as primaquine. For this reason it is imperative to identify individuals with G6PD deficiency prior to administering these anti-malarial drugs. There is a need for the development and evaluation of point-of-care G6PD deficiency screening tests suitable for areas of the developing world where malarial treatments are frequently administered. The development and evaluation of new G6PD tests will be greatly assisted with the availability of specimen repositories. Cryopreservation of erythrocytes was evaluated as a means to preserve G6PD activity. Blood specimens from 31 patients including ten specimens with normal G6PD activity, three with intermediate activity, and 18 with deficient activity were cryopreserved for up to six months. Good correlation in G6PD activity between fresh and cryopreserved specimens (R2 = 0.95). The cryopreserved specimens show an overall small drop in mean G6PD activity of 0.23 U/g Hb (P=0.23). Cytochemical staining showed that intracellular G6PD activity distribution within the red blood cell populations is preserved during cryopreservation. Furthermore, the mosaic composition of red blood cells in heterozygous women is also preserved for six months or more. The fluorescent spot and the BinaxNOW qualitative tests for G6PD deficiency also showed high concordance in G6PD status determination between cryopreserved specimens and fresh specimens. A methodology for establishing a specimen panel for evaluation of G6PD tests is described. The approach is similar to that used in several malaria research facilities for the cryopreservation of parasites in clinical specimens and axenic cultures. Specimens stored in this manner will aid both the development and evaluation of

  9. Glucose-6-phosphate dehydrogenase deficiency and sulfadimidin acetylation phenotypes in Egyptian oases.

    PubMed

    Hussein, L; Yamamah, G; Saleh, A

    1992-04-01

    Screening of 1315 males from two Egyptian oases for glucose-6-phosphate dehydrogenase deficiency (G-6PD) found an incidence of 5.9%. The rate of acetylation of sulfadimidin was also studied, and a bimodal distribution was found with 73% rapid acetylators. There is a correlation between high frequency of G-6PD deficiency and high frequency of slow acetylation rate.

  10. Glucose-6-phosphate dehydrogenase-derived NADPH fuels superoxide production in the failing heart

    USDA-ARS?s Scientific Manuscript database

    In the failing heart, NADPH oxidase and uncoupled NO synthase utilize cytosolic NADPH to form superoxide. NADPH is supplied principally by the pentose phosphate pathway, whose rate-limiting enzyme is glucose 6-phosphate dehydrogenase (G6PD). Therefore, we hypothesized that cardiac G6PD activation dr...

  11. Prevalence of glucose-6-phosphate dehydrogenase deficiency in jaundiced Egyptian neonates.

    PubMed

    M Abo El Fotoh, Wafaa Moustafa; Rizk, Mohammed Soliman

    2016-12-01

    The enzyme, Glucose-6-phosphate dehydrogenase (G6PD), deficiency leads to impaired production of reduced glutathione and predisposes the red cells to be damaged by oxidative metabolites, causing hemolysis. Deficient neonates may manifest clinically as hyperbilirubinemia or even kernicterus. This study was carried out to detect erythrocyte G6PD deficiency in neonatal hyperbilirubinemia. To determine the frequency and effect of G6PD deficiency, this study was conducted on 202 neonates with indirect hyperbilirubinemia. All term and preterm babies up to 13 day of age admitted with clinically evident jaundice were taken for the study. G6PD activity is measured by the UV-Kinetic Method using cellular enzyme determination reagents by spectrophotometry according to manufacturer's instructions. A total of 202 babies were enrolled in this study. Male babies outnumbered the female (71.3% versus 28.7%). Mean age of the study newborns was 3.75 ± 2.5 days. Eighteen neonates (8.9%) had G6PD deficiency, all are males. One case had combined G6PD deficiency and RH incompatibility. Mean serum total bilirubin was 17.2 ± 4.4 in G6PD deficient cases. There was significant positive correlation between the time of appearance of jaundice in days and G6PD levels in G6PD deficient cases. Neonatal hyperbilirubinemia is associated with various clinical comorbidities. G6PD deficiency is found to one important cause of neonatal jaundice developing on day 2 onwards.

  12. DHEA prevents ribavirin-induced anemia via inhibition of glucose-6-phosphate dehydrogenase.

    PubMed

    Handala, Lynda; Domange, Barbara; Ouled-Haddou, Hakim; Garçon, Loïc; Nguyen-Khac, Eric; Helle, Francois; Bodeau, Sandra; Duverlie, Gilles; Brochot, Etienne

    2017-09-08

    Ribavirin has been widely used for antiviral therapy. Unfortunately, ribavirin-induced anemia is often a cause of limiting or interrupting treatment. Our team has observed that dehydroepiandrosterone (DHEA) has a protective effect against in vitro and in vivo ribavirin-induced hemolysis. The aim of this study was to better understand this effect as well as the underlying mechanism(s). DHEA was able to reduce in vitro intraerythrocytic ATP depletion induced by ribavirin. Only 1% of ATP remained after incubation with ribavirin (2 mM) at 37 °C for 24 h vs. 37% if DHEA (200 μM) was added (p < 0.01). DHEA also helped erythrocytes conserve their size, with a shrinkage of only 10% vs 40% at 24 h with ribavirin alone (p < 0.01), and reduced phosphatidylserine exposure at the outer membrane, i.e. 27% vs 40% at 48 h, (p < 0.05). DHEA also inhibits ribavirin-induced hemolysis, i.e. 34% vs 46.5% at 72 h (p < 0.01). DHEA is an inhibitor of glucose-6-phosphate dehydrogenase (G6PD), a key enzyme in the hexose monophosphate shunt connected to the glycolytic pathway which is the only energy supplier of the red blood cell in the form of ATP. We have confirmed this inhibitory effect in the presence of ribavirin. All these observations suggest that ribavirin-induced hemolysis was initiated by ATP depletion, and that the inhibitory effect of DHEA on G6PD was able to rescue enough ATP to limit this hemolysis. This mechanism could be important for improving the therapeutic management of patients treated with ribavirin. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Glucose-6-phosphate mediates activation of the carbohydrate responsive binding protein (ChREBP)

    SciTech Connect

    Li, Ming V.; Chen, Weiqin; Harmancey, Romain N.; Nuotio-Antar, Alli M.; Imamura, Minako; Saha, Pradip; Taegtmeyer, Heinrich; Chan, Lawrence

    2010-05-07

    Carbohydrate response element binding protein (ChREBP) is a Mondo family transcription factor that activates a number of glycolytic and lipogenic genes in response to glucose stimulation. We have previously reported that high glucose can activate the transcriptional activity of ChREBP independent of the protein phosphatase 2A (PP2A)-mediated increase in nuclear entry and DNA binding. Here, we found that formation of glucose-6-phosphate (G-6-P) is essential for glucose activation of ChREBP. The glucose response of GAL4-ChREBP is attenuated by D-mannoheptulose, a potent hexokinase inhibitor, as well as over-expression of glucose-6-phosphatase (G6Pase); kinetics of activation of GAL4-ChREBP can be modified by exogenously expressed GCK. Further metabolism of G-6-P through the two major glucose metabolic pathways, glycolysis and pentose-phosphate pathway, is not required for activation of ChREBP; over-expression of glucose-6-phosphate dehydrogenase (G6PD) diminishes, whereas RNAi knockdown of the enzyme enhances, the glucose response of GAL4-ChREBP, respectively. Moreover, the glucose analogue 2-deoxyglucose (2-DG), which is phosphorylated by hexokinase, but not further metabolized, effectively upregulates the transcription activity of ChREBP. In addition, over-expression of phosphofructokinase (PFK) 1 and 2, synergistically diminishes the glucose response of GAL4-ChREBP. These multiple lines of evidence support the conclusion that G-6-P mediates the activation of ChREBP.

  14. Patient with toxoplasmosis and glucose-6-phosphate dehydrogenase deficiency: a case report

    PubMed Central

    Nunes, Altacílio A

    2009-01-01

    Introduction Toxoplasmosis, a zoonotic protozoal disease caused by toxoplasma gondii, is prevalent throughout the world, affecting a large proportion of persons who usually have no symptoms. Glucose 6 phosphate dehydrogenase deficiency, an X-linked inherited disorder, is present in over 400 million people world wide. It is more common in tropical and subtropical countries and is one of the important causes of hemolytic anemia. Case presentation This case report relates the occurrence of the two diseases simultaneously in a child of five years old. Conclusion Patients with glucose-6-phosphate dehydrogenase deficiency are more susceptible to toxoplasmosis and this case report, reinforce the findings of this propensity and alert us for such possibility, what it is important, therefore, the treatment of toxoplasmosis can cause serious hemolysis in these patients. PMID:19918404

  15. Molecular Analysis of the Gene Encoding F420-Dependent Glucose-6-Phosphate Dehydrogenase from Mycobacterium smegmatis

    PubMed Central

    Purwantini, Endang; Daniels, Lacy

    1998-01-01

    The gene fgd, which codes for F420-dependent glucose-6-phosphate dehydrogenase (FGD), was cloned from Mycobacterium smegmatis, and its sequence was determined and analyzed. A homolog of FGD which has a very high similarity to the M. smegmatis FGD-derived amino acid sequence was identified in Mycobacterium tuberculosis. FGD showed significant homology with F420-dependent N5,N10-methylene-tetrahydromethanopterin reductase (MER) from methanogenic archaea and with several hypothetical proteins from M. tuberculosis and Archaeoglobus fulgidus, but FGD showed no significant homology with NADP-dependent glucose-6-phosphate dehydrogenases. Multiple alignment of FGD and MER proteins revealed four conserved consensus sequences. Multiple alignment of FGD with the hypothetical proteins also revealed portions of the same conserved sequences. Moderately high levels of FGD were expressed in Escherichia coli BL21(DE3) carrying fgd in pBluescript. PMID:9555906

  16. Apparent role of dynein in glucose-6-phosphate dehydrogenase trafficking in neutrophils from pregnant women.

    PubMed

    Huang, Ji-Biao; Espinoza, Jimmy; Romero, Roberto; Petty, Howard R

    2006-03-01

    To better understand the mechanisms of metabolic microcompartmentalization associated with neutrophil hexose monophosphate shunt activity during pregnancy, we have studied the intracellular trafficking of glucose-6-phosphate dehydrogenase (G6PDase). Microtubule motor proteins colocalize with G6PDase. Dynein inhibitors block G6PDase accumulation at the microtubule-organizing center in pregnancy cells. On this basis, we conclude that microtubule motor proteins participate in hexose monophosphate shunt enzyme transport within leukocytes.

  17. Glucose-6-phosphate Reduces Calcium Accumulation in Rat Brain Endoplasmic Reticulum

    DTIC Science & Technology

    2012-04-01

    low millimolar range. Most Ca2+ is sequestered within organelles , including the endoplasmic reticulum (ER), Golgi, mitochondria , and nucleus (Carafoli...G6P and thapsigargin caused generalized reduction in Ca2+ accumulation in remarkably similar patterns with no apparent gray matter regional...with glucose-6-phosphate (10 mM) or thapsigargin (1 µM), revealed very similar pattern of generalized reduction in 45Ca2+ accumulation in gray and

  18. Aortic valve replacement for a patient with glucose-6-phosphate dehydrogenase deficiency and autoimmune hemolytic anemia.

    PubMed

    Tas, Serpil; Donmez, Arzu Antal; Kirali, Kaan; Alp, Mete H; Yakut, Cevat

    2005-01-01

    Autoimmune hemolytic anemia and deficiency of glucose-6-phosphate deyhdrogenase (G6PD) result in severe hemolysis with different mechanisms. In patients with both pathologies, the effects of cardiopulmonary bypass on red blood cells and thrombocytes demand special care before and after open heart surgery. We evaluated the preoperative management and postoperative care of a patient with severe aortic insufficiency associated with G6PD deficiency and autoimmune hemolytic anemia who underwent aortic valve replacement.

  19. Androgen-estrogen synergy in rat levator ani muscle Glucose-6-phosphate dehydrogenase

    NASA Technical Reports Server (NTRS)

    Max, S. R.

    1984-01-01

    The effects of castration and hormone administration on the activity of glucose-6-phosphate dehydrogenase in the rat levator ani muscle were studied. Castration caused a decrease in enzyme activity and in wet weight of the levator ani muscle. Chronic administration of testosterone propionate increased glucose-6-phosphate dehydrogenase activity in the levator ani muscle of castrated rats; the magnitude of the recovery of enzyme activity was related to the length of time of exposure to testosterone propionate after castration as well as to the length of time the animals were castrated. The longer the period of castration before exposure to testosterone propionate, the greater the effect. This result may be related to previously reported castration-mediated increases in androgen receptor binding in muscle. Dihydrotestosterone was less effective than testosterone propionate in enhancing glucose-6-phosphate dehydrogenase activity in the levator ani muscle from castrated rats; estradiol-17-beta alone was ineffective. Combined treatment with estradiol-17-beta and dihydrotestosterone, however, was as effective as testosterone alone. Thus, androgens and estrogens may exert synergistic effects on levator ani muscle.

  20. Ischaemic Priapism and Glucose-6-Phosphate Dehydrogenase Deficiency: A Mechanism of Increased Oxidative Stress?

    PubMed

    Morrison, B F; Thompson, E B; Shah, S D; Wharfe, G H

    2014-07-03

    Ischaemic priapism is a devastating urological condition that has the potential to cause permanent erectile dysfunction. The disorder has been associated with numerous medical conditions and the use of pharmacotherapeutic agents. The aetiology is idiopathic in a number of cases. There are two prior case reports of the association of ischaemic priapism and glucose-6-phosphate dehydrogenase (G6PD) deficiency. We report on a third case of priapism associated with G6PD deficiency and review recently described molecular mechanisms of increased oxidative stress in the pathophysiology of ischaemic priapism. The case report of a 32-year old Afro-Caribbean male with his first episode of major ischaemic priapism is described. Screening for common causes of ischaemic priapism, including sickle cell disease was negative. Glucose-6-phosphate dehydrogenase deficiency was discovered on evaluation for priapism. Penile aspiration was performed and erectile function was good post treatment.Glucose-6-phosphate dehydrogenase deficiency is a cause for ischaemic priapism and should be a part of the screening process in idiopathic causes of the disorder. Increased oxidative stress occurs in G6PD deficiency and may lead to priapism.

  1. Androgen-estrogen synergy in rat levator ani muscle Glucose-6-phosphate dehydrogenase

    NASA Technical Reports Server (NTRS)

    Max, S. R.

    1984-01-01

    The effects of castration and hormone administration on the activity of glucose-6-phosphate dehydrogenase in the rat levator ani muscle were studied. Castration caused a decrease in enzyme activity and in wet weight of the levator ani muscle. Chronic administration of testosterone propionate increased glucose-6-phosphate dehydrogenase activity in the levator ani muscle of castrated rats; the magnitude of the recovery of enzyme activity was related to the length of time of exposure to testosterone propionate after castration as well as to the length of time the animals were castrated. The longer the period of castration before exposure to testosterone propionate, the greater the effect. This result may be related to previously reported castration-mediated increases in androgen receptor binding in muscle. Dihydrotestosterone was less effective than testosterone propionate in enhancing glucose-6-phosphate dehydrogenase activity in the levator ani muscle from castrated rats; estradiol-17-beta alone was ineffective. Combined treatment with estradiol-17-beta and dihydrotestosterone, however, was as effective as testosterone alone. Thus, androgens and estrogens may exert synergistic effects on levator ani muscle.

  2. An optimised system for refolding of human glucose 6-phosphate dehydrogenase

    PubMed Central

    Wang, Xiao-Tao; Engel, Paul C

    2009-01-01

    Background Human glucose 6-phosphate dehydrogenase (G6PD), active in both dimer and tetramer forms, is the key entry enzyme in the pentose phosphate pathway (PPP), providing NADPH for biosynthesis and various other purposes, including protection against oxidative stress in erythrocytes. Accordingly haemolytic disease is a major consequence of G6PD deficiency mutations in man, and many severe disease phenotypes are attributed to G6PD folding problems. Therefore, a robust refolding method with high recovery yield and reproducibility is of particular importance to study those clinical mutant enzymes as well as to shed light generally on the refolding process of large multi-domain proteins. Results The effects of different chemical and physical variables on the refolding of human recombinant G6PD have been extensively investigated. L-Arg, NADP+ and DTT are all major positive influences on refolding, and temperature, protein concentration, salt types and other additives also have significant impacts. With the method described here, ~70% enzyme activity could be regained, with good reproducibility, after denaturation with Gdn-HCl, by rapid dilution of the protein, and the refolded enzyme displays kinetic and CD properties indistinguishable from those of the native protein. Refolding under these conditions is relatively slow, taking about 7 days to complete at room temperature even in the presence of cyclophilin A, a peptidylprolyl isomerase reported to increase refolding rates. The refolded protein intermediates shift from dominant monomer to dimer during this process, the gradual emergence of dimer correlating well with the regain of enzyme activity. Conclusion L-Arg is the key player in the refolding of human G6PD, preventing the aggregation of folding intermediate, and NADP+ is essential for the folding intermediate to adopt native structure. The refolding protocol can be applied to produce high recovery yield of folded protein with unaltered properties, paving the

  3. Glucose-6-phosphate dehydrogenase deficiency prevalence and genetic variants in malaria endemic areas of Colombia.

    PubMed

    Valencia, Sócrates Herrera; Ocampo, Iván Darío; Arce-Plata, María Isabel; Recht, Judith; Arévalo-Herrera, Myriam

    2016-05-26

    Glucose 6-phosphate dehydrogenase (G6PD) is an enzyme involved in prevention of cellular oxidative damage, particularly protecting erythrocytes from haemolysis. An estimated 400 million people present variable degrees of inherited G6PD deficiency (G6PDd) which puts them at risk for developing haemolysis triggered by several risk factors including multiple drugs and certain foods. Primaquine (PQ) is a widely used anti-malarial drug that can trigger haemolysis in individuals with G6PDd. Intensification of malaria control programmes worldwide and particularly malaria elimination planning in some regions recommend a more extensive use of PQ and related drugs in populations with different G6PDd prevalence. This a preliminary study to assess the prevalence of G6PDd in representative malaria endemic areas of Colombia by measuring G6PD phonotype and genotypes. Volunteers (n = 426) from four malaria endemic areas in Colombia (Buenaventura, Tumaco, Tierralta and Quibdo) were enrolled. Blood samples were drawn to evaluate G6PD enzymatic activity by using a quantitative G6PD test and a subset of samples was analysed by PCR-RFLP to determine the frequency of the three most common G6PD genotypic variants: A-, A+ and Mediterranean. A total of 28 individuals (6.56 %) displayed either severe or intermediate G6PDd. The highest prevalence (3.51 %) was in Buenaventura, whereas G6PDd prevalence was lower (<1 %) in Tierralta and Quibdo. G6PD A alleles were the most frequent (15.23 %) particularly in Buenaventura and Tumaco. Overall, a high frequency of G6PD A- genotype, followed by A+ genotype was found in the analysed population. G6PDd based on enzymatic activity as well as G6PD A allelic variants were found in malaria-endemic populations on the Pacific coast of Colombia, where most of malaria cases are caused by Plasmodium vivax infections. These infections are treated for 14 days with PQ, however there are no official reports of PQ-induced haemolytic crises. Further

  4. Changing kinetic properties of glucose-6-phosphate dehydrogenase from pea chloroplasts during photosynthetic induction

    SciTech Connect

    Yuan, X.; Anderson, L.E.

    1987-04-01

    The first enzyme of the oxidative pentose phosphate pathway, glucose-6-P dehydrogenase (EC 1.1.1.49), is inactivated when pea chloroplasts are irradiated. They have examined the kinetics of light inactivation of glucose-6-P dehydrogenase in intact chloroplasts during photosynthetic induction and the kinetic parameters of the active (dark) and less active (light) form of the dehydrogenase. Light inactivation of the dehydrogenase is rapid and occurs before photosynthetic O/sub 2/ evolution is measureable in intact chloroplasts. Likewise dark activation is quite rapid. The major change in the kinetic parameters of glucose-6-phosphate dehydrogenase is in maximal velocity. This light inactivation probably prevents operation of a futile cycle involving glucose-6-P, NADPH and oxidative and reductive pentose phosphate pathway enzymes.

  5. Gas Phase Spectra and Structural Determination of Glucose 6 Phosphate Using Cryogenic Ion Vibrational Spectroscopy

    NASA Astrophysics Data System (ADS)

    Kregel, Steven J.; Voss, Jonathan; Marsh, Brett; Garand, Etienne

    2014-06-01

    Glucose-6-Phosphate (G6P) is one member of a class of simple phosphorylated sugars that are relevant in biological processes. We have acquired a gas phase infrared spectrum of G6P- using cryogenic ion vibrational spectroscopy (CIVS) in a home-built spectrometer. The experimental spectrum was compared with calculated vibrational spectra from a systematic conformer search. For both of the α and β anomers, results show that only the lowest energy conformers are present in the gas phase. If spectral signatures for similar sugars could be cataloged, it would allow for conformer-specific determination of mixture composition, for example, for glycolyzation processes.

  6. Bio-catalytic nanocompartments for in situ production of glucose-6-phosphate.

    PubMed

    Lomora, M; Gunkel-Grabole, G; Mantri, S; Palivan, C G

    2017-08-29

    Cells are sophisticated biocatalytic systems driving a complex network of biochemical reactions. A bioinspired strategy to create advanced functional systems is to design confined spaces for complex enzymatic reactions by using a combination of synthetic polymer assemblies and natural cell components. Here, we developed bio-catalytic nanocompartments that contain phosphoglucomutase protected by a biomimetic polymer membrane, which was permeabilized for reactants through insertion of an engineered α-hemolysin pore protein. These bio-catalytic nanocompartments serve for production of glucose-6-phosphate, and thus possess great potential for applications in an incomplete glycolysis, pentose phosphate pathway, or in plant biological reactions.

  7. Glucose-6-Phosphate Dehydrogenase Deficiency and Haemoglobinophaties in Resident of Arso PIR, Irian Jaya

    DTIC Science & Technology

    1990-01-01

    and drug treatment . Another factor is play a part in innate resistance. 0-6-PD the ’internal environment’ of the host and deficiency can also complicate...response to and treatment of glucose-6-phosphate. The amount of of malaria, epidemiologic and immuno- NADPH produced is detected spectropho- logic...Ohio inherited along with a B- thalassemia gene 9-66. producing Hb-E thalassemia . Although 2. Kellermeyer, R.W., A.R. Tarlov, G.J. this condition can

  8. Glucose-6-phosphate dehydrogenase deficiency: an unusual cause of acute jaundice after paracetamol overdose.

    PubMed

    Phillpotts, Simon; Tash, Elliot; Sen, Sambit

    2014-11-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the commonest human enzyme defect causing haemolytic anaemia after exposure to specific triggers. Paracetamol-induced haemolysis in G6PD deficiency is a rare complication and mostly reported in children. We report the first case (to the best of our knowledge) of acute jaundice without overt clinical features of a haemolytic crisis, in an otherwise healthy adult female following paracetamol overdose, due to previously undiagnosed G6PD deficiency. It is important that clinicians consider this condition when a patient presents following a paracetamol overdose with significant and disproportionate jaundice, without transaminitis or coagulopathy.

  9. Glucose-6-phosphate dehydrogenase deficiency in the Greek population of Cape Town.

    PubMed

    Bonafede, R P; Botha, M C; Beighton, P

    1984-04-07

    A sample of 250 unrelated members of the Greek community of Cape Town was studied in order to establish the prevalence of glucose-6-phosphate dehydrogenase (G-6-PD) deficiency in the community. A gene frequency of 0,067 in males and a prevalence of 6,7% are estimated for this group. It is recommended that persons with G-6-PD deficiency should have access to a list of medicinal agents which have the potential for precipitating acute haemolytic crises and that they should wear Medic-Alert discs bearing information concerning the disorder.

  10. Fed-Batch Production of Glucose 6-Phosphate Dehydrogenase Using Recombinant Saccharomyces cerevisiae

    NASA Astrophysics Data System (ADS)

    Das Neves, Luiz Carlos Martins; Pessoa, Adalberto; Vitolo, Michele

    The strain Saccharomyces cerevisiae W303-181, having the plasmid YEpPGK-G6P (built by coupling the vector YEPLAC 181 with the promoter phosphoglycerate kinase 1), was cultured by fed-batch process in order to evaluate its capability in the formation of glucose 6-phosphate dehydrogenase (EC.1.1.1.49). Two liters of culture medium (10.0 g/L glucose, 3.7 g/L yeast nitrogen broth (YNB), 0.02 g/L l-tryptophan, 0.02 g/L l-histidine, 0.02 g/L uracil, and 0.02 g/L adenine) were inoculated with 1.5 g dry cell/L and left fermenting in the batch mode at pH 5.7, aeration of 2.2 vvm, 30°C, and agitation of 400 rpm. After glucose concentration in the medium was lower than 1.0 g/L, the cell culture was fed with a solution of glucose (10.0 g/L) or micronutrients (l-tryptophan, l-histidine, uracil, and adenine each one at a concentration of 0.02 g/L) following the constant, linear, or exponential mode. The volume of the culture medium in the fed-batch process was varied from 2 L up to 3 L during 5 h. The highest glucose 6-phosphate dehydrogenase activity (350 U/L; 1 U=1 μmol of NADP/min) occurred when the glucose solution was fed into the fermenter through the decreasing linear mode.

  11. Differential behaviour of glucose 6-phosphate dehydrogenase in two morphological forms of Trypanosoma cruzi.

    PubMed

    Lupiañez, J A; Adroher, F J; Vargas, A M; Osuna, A

    1987-01-01

    1. Glucose 6-phosphate dehydrogenase activity (EC 1.1.1.49) of two morphological forms of Trypanosoma cruzi, epimastigotes and metacyclics, are reported. 2. The kinetic behaviour and some of the kinetic parameters of the enzyme in both forms were studied. The enzymes showed a simple Michaelis-Menten kinetic. 3. The activity in epimastigote forms was alway higher than the metacyclic ones. At subsaturating concentrations of substrate was almost 10-fold higher, whereas at saturating concentrations was about 2-fold higher. 4. In epimastigote forms the specific activity and Km values, at pH 7.5 and 37 degrees C, was found to be 142 mUnits x mg-1 of protein and 0.23 mM, respectively. 5. In the same conditions, the specific activity and Km values in metacyclic forms was 75 mUnits x mg-1 of protein and 1.06 mM, respectively. 6. A possible role in the carbohydrate metabolism of glucose 6-phosphate dehydrogenase in both forms of Trypanosoma cruzi is discussed.

  12. Purification of a novel coenzyme F420-dependent glucose-6-phosphate dehydrogenase from Mycobacterium smegmatis.

    PubMed Central

    Purwantini, E; Daniels, L

    1996-01-01

    A variety of Mycobacterium species contained the 5-deazaflavin coenzyme known as F420. Mycobacterium smegmatis was found to have a glucose-6-phosphate dehydrogenase that was dependent on F420 as an electron acceptor and which did not utilize NAD or NADP. The enzyme was purified by ammonium sulfate fractionation, phenyl-Sepharose column chromatography, F420-ether-linked aminohexyl-Sepharose 4B affinity chromatography, and quaternary aminoethyl-Sephadex column chromatography, and the sequence of the first 26 N-terminal amino acids has been determined. The response of enzyme activity to a range of pHs revealed a two-peak pattern, with maxima at pH 5.5 and 8.0. The apparent Km values for F420 and glucose-6-phosphate were, respectively, 0.004 and 1.6 mM. The apparent native and subunit molecular masses were 78,000 and approximately 40,000 Da, respectively. PMID:8631674

  13. Glucose-6-phosphate dehydrogenase deficiency and Alzheimer's disease: Partners in crime? The hypothesis.

    PubMed

    Ulusu, N Nuray

    2015-08-01

    Alzheimer's disease is a multifaceted brain disorder which involves various coupled irreversible, progressive biochemical reactions that significantly reduce quality of life as well as the actual life expectancy. Aging, genetic predispositions, head trauma, diabetes, cardiovascular disease, deficiencies in insulin signaling, dysfunction of mitochondria-associated membranes, cerebrovascular changes, high cholesterol level, increased oxidative stress and free radical formation, DNA damage, disturbed energy metabolism, and synaptic dysfunction, high blood pressure, obesity, dietary habits, exercise, social engagement, and mental stress are noted among the risk factors of this disease. In this hypothesis review I would like to draw the attention on glucose-6-phosphate dehydrogenase deficiency and its relationship with Alzheimer's disease. This enzymopathy is the most common human congenital defect of metabolism and defined by decrease in NADPH+H(+) and reduced form of glutathione concentration and that might in turn, amplify oxidative stress due to essentiality of the enzyme. This most common enzymopathy may manifest itself in severe forms, however most of the individuals with this deficiency are not essentially symptomatic. To understand the sporadic Alzheimer's disease, the writer of this paper thinks that, looking into a crystal ball might not yield much of a benefit but glucose-6-phosphate dehydrogenase deficiency could effortlessly give some clues. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Glucose-6-Phosphate Dehydrogenase Protects Escherichia coli from Tellurite-Mediated Oxidative Stress

    PubMed Central

    Sandoval, Juan M.; Arenas, Felipe A.; Vásquez, Claudio C.

    2011-01-01

    The tellurium oxyanion tellurite induces oxidative stress in most microorganisms. In Escherichia coli, tellurite exposure results in high levels of oxidized proteins and membrane lipid peroxides, inactivation of oxidation-sensitive enzymes and reduced glutathione content. In this work, we show that tellurite-exposed E. coli exhibits transcriptional activation of the zwf gene, encoding glucose 6-phosphate dehydrogenase (G6PDH), which in turn results in augmented synthesis of reduced nicotinamide adenine dinucleotide phosphate (NADPH). Increased zwf transcription under tellurite stress results mainly from reactive oxygen species (ROS) generation and not from a depletion of cellular glutathione. In addition, the observed increase of G6PDH activity was paralleled by accumulation of glucose-6-phosphate (G6P), suggesting a metabolic flux shift toward the pentose phosphate shunt. Upon zwf overexpression, bacterial cells also show increased levels of antioxidant molecules (NADPH, GSH), better-protected oxidation-sensitive enzymes and decreased amounts of oxidized proteins and membrane lipids. These results suggest that by increasing NADPH content, G6PDH plays an important role in E. coli survival under tellurite stress. PMID:21984934

  15. Extremely high intracellular concentration of glucose-6-phosphate and NAD(H) in Deinococcus radiodurans.

    PubMed

    Yamashiro, Takumi; Murata, Kousaku; Kawai, Shigeyuki

    2017-03-01

    Deinococcus radiodurans is highly resistant to ionizing radiation and UV radiation, and oxidative stress caused by such radiations. NADP(H) seems to be important for this resistance (Slade and Radman, Microbiol Mol Biol Rev 75:133-191; Slade, Radman, Microbiol Mol Biol Rev 75:133-191, 2011), but the mechanism underlying the generation of NADP(H) or NAD(H) in D. radiodurans has not fully been addressed. Intracellular concentrations of NAD(+), NADH, NADP(+), and NADPH in D. radiodurans are also not determined yet. We found that cell extracts of D. radiodurans catalyzed reduction of NAD(P)(+) in vitro, indicating that D. radiodurans cells contain both enzymes and a high concentration of substrates for this activity. The enzyme and the substrate were attributed to glucose-6-phosphate dehydrogenase and glucose-6-phosphate of which intracellular concentration was extremely high. Unexpectedly, the intracellular concentration of NAD(H) was also much greater than that of NADP(H), suggesting some significant roles of NADH. These unusual features of this bacterium would shed light on a new aspect of physiology of this bacterium.

  16. Comparison of glucose, glucose 6-phosphate, ribose, and mannose as flavour precursors in pork; the effect of monosaccharide addition on flavour generation.

    PubMed

    Meinert, Lene; Schäfer, Annette; Bjergegaard, Charlotte; Aaslyng, Margit D; Bredie, Wender L P

    2009-03-01

    The effect of glucose, glucose 6-phosphate, mannose and ribose on the generation of aroma volatiles in pork was investigated. The monosaccharides were added individually to minced pork prior to heat treatment (160°C for 10min) in the following concentrations: glucose (27.5μmol/g), ribose (1.2μmol/g), mannose (8.3μmol/g) and glucose 6-phosphate (0.5μmol/g). The natural concentrations of the monosaccharides in the pork used were found to be 4.0μmol/g for glucose, 0.1μmol/g for ribose, 0.3μmol/g for mannose and 2.6μmol/g for glucose 6-phosphate. The major aroma compounds identified in the headspace of the heated samples were pyrazines, aldehydes (Strecker and lipid-derived), ketones, and sulphides. Glucose generated the highest amounts of volatiles followed by glucose 6-phosphate. However, when related to the added concentration of glucose 6-phosphate, this phosphorylated monosaccharide showed the highest aroma generating potential. The addition of ribose did not increase the concentration of volatiles compared with pork without the added monosaccharide. The fates of ribose 5-phosphate and ribose in pork were studied over time. The concentrations of ribose and ribose 5-phosphate clearly decreased during 2h equilibration, which may be due to enzymatic activities. These precursors may, therefore, be less important pork flavour precursors than glucose and glucose 6-phosphate.

  17. Apert syndrome with glucose-6-phosphate dehydrogenase deficiency: a case report.

    PubMed

    Tosun, G; Sener, Y

    2006-05-01

    Apert syndrome is characterized by midface hypoplasia, syndactyly of the hands and feet, proptosis of eyes, steep and flat frontal bones, and premature union of cranial sutures. Maxillary hypoplasia, deep palatal vault, anterior open bite, crowding of the dental arch, severely delayed tooth eruption, and dental malocclusion are the main oral manifestations of this syndrome. In this report, a case of Apert syndrome with glucose-6-phosphate dehydrogenase (G(6)PD) deficiency is presented. The patient, a 4-year-old male and the fourth child of healthy parents, was admitted to our department because of delayed tooth eruption. He had all the cardinal symptoms of the Apert syndrome. Clinical examination revealed that primary centrals, canines and first molars erupted; however, primary second molars and laterals had not erupted. The patient had no dental caries. Preventive treatments were applied, and subsequently, the patient was taken to long-term follow up.

  18. Glucose-6-Phosphate Dehydrogenase of Trypanosomatids: Characterization, Target Validation, and Drug Discovery

    PubMed Central

    Gupta, Shreedhara; Igoillo-Esteve, Mariana; Michels, Paul A. M.; Cordeiro, Artur T.

    2011-01-01

    In trypanosomatids, glucose-6-phosphate dehydrogenase (G6PDH), the first enzyme of the pentosephosphate pathway, is essential for the defense of the parasite against oxidative stress. Trypanosoma brucei, Trypanosoma cruzi, and Leishmania mexicana G6PDHs have been characterized. The parasites' G6PDHs contain a unique 37 amino acid long N-terminal extension that in T. cruzi seems to regulate the enzyme activity in a redox-state-dependent manner. T. brucei and T. cruzi G6PDHs, but not their Leishmania spp. counterpart, are inhibited, in an uncompetitive way, by steroids such as dehydroepiandrosterone and derivatives. The Trypanosoma enzymes are more susceptible to inhibition by these compounds than the human G6PDH. The steroids also effectively kill cultured trypanosomes but not Leishmania and are presently considered as promising leads for the development of new parasite-selective chemotherapeutic agents. PMID:22091394

  19. Should we screen newborns for glucose-6-phosphate dehydrogenase deficiency in the United States?

    PubMed

    Watchko, J F; Kaplan, M; Stark, A R; Stevenson, D K; Bhutani, V K

    2013-07-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency, a common X-linked enzymopathy can lead to severe hyperbilirubinemia, acute bilirubin encephalopathy and kernicterus in the United States. Neonatal testing for G6PD deficiency is not yet routine and the American Academy of Pediatrics recommends testing only in jaundiced newborns who are receiving phototherapy whose family history, ethnicity, or geographic origin suggest risk for the condition, or for infants whose response to phototherapy is poor. Screening tests for G6PD deficiency are available, are suitable for use in newborns and have been used in birth hospitals. However, US birth hospitals experience is limited and no national consensus has emerged regarding the need for newborn G6PD testing, its effectiveness or the best approach. Our review of current state of G6PD deficiency screening highlights research gaps and informs specific operational challenges to implement universal newborn G6PD testing concurrent to bilirubin screening in the United States.

  20. Molecular analysis of glucose-6-phosphate dehydrogenase variants in the Solomon Islands

    SciTech Connect

    Hirono, A.; Ishii, A.; Hirono, K.; Miwa, S.; Kere, N.; Fujii, H.

    1995-05-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most prevalent genetic disorders, and >100 million people are considered to have mutant genes. G6PD deficiency is frequent in the area where plasmodium falciparum infection is endemic, probably because the G6PD-deficient subjects are resistant to the parasite. Falciparum and vivax malarias have been highly endemic in the Solomon Islands, and a high frequency of G6PD deficiency has also been expected. A recent investigation showed that the frequency of G6PD deficiency in the Solomon Islands was 8.4%-14.4%. Although >80 G6PD variants from various populations have been molecularly analyzed, little is known about those in Melanesians. G6PD Maewo, which was originally found in Vanuatu, has so far been the only Melanesian variant whose structural abnormality was determined. 14 refs., 1 fig.

  1. Cloning, expression, purification and characterization of his-tagged human glucose-6-phosphate dehydrogenase: a simplified method for protein yield.

    PubMed

    Gómez-Manzo, Saúl; Terrón-Hernández, Jessica; de la Mora-de la Mora, Ignacio; García-Torres, Itzhel; López-Velázquez, Gabriel; Reyes-Vivas, Horacio; Oria-Hernández, Jesús

    2013-10-01

    Glucose-6-phosphate dehydrogenase (G6PD) catalyzes the first step of the pentose phosphate pathway. In erythrocytes, the functionality of the pathway is crucial to protect these cells against oxidative damage. G6PD deficiency is the most frequent enzymopathy in humans with a global prevalence of 4.9 %. The clinical picture is characterized by chronic or acute hemolysis in response to oxidative stress, which is related to the low cellular activity of G6PD in red blood cells. The disease is heterogeneous at genetic level with around 160 mutations described, mostly point mutations causing single amino acid substitutions. The biochemical studies aimed to describe the detrimental effects of mutations on the functional and structural properties of human G6PD are indispensable to understand the molecular physiopathology of this disease. Therefore, reliable systems for efficient expression and purification of the protein are highly desirable. In this work, human G6PD was heterologously expressed in Escherichia coli and purified by immobilized metal affinity chromatography in a single chromatographic step. The structural and functional characterization indicates that His-tagged G6PD resembles previous preparations of recombinant G6PD. In contrast with previous protein yield systems, our method is based on commonly available resources and fully accessible laboratory equipment; therefore, it can be readily implemented.

  2. Effect of chronologic age on induction of cystathionine synthase, uroporphyrinogen I synthase, and glucose-6-phosphate dehydrogenase activities in lymphocytes.

    PubMed Central

    Gartler, S M; Hornung, S K; Motulsky, A G

    1981-01-01

    The activities of cystathionine synthase [L-serine hydro-lyase (adding homocysteine), EC 4.2.1.22], uroporphyrinogen I synthase [porphobilinogen ammonia-lyase (polymerizing), EC 4.3.1.8], and glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate:NADP+ 1-oxidoreductase, EC 1.1.1.49) have been measured in phytohemagglutinin-stimulated lymphocytes of young and old human subjects. A significant decrease in activity with age was observed for cystathionine synthase and uroporphyrinogen I synthase but not for glucose-6-phosphate dehydrogenase. These changes could not be related to declining phytohemagglutinin response with aging. Age-related decreases in activity of some enzymes may be relevant for an understanding of the biology of aging. False assignment of heterozygosity, and even homozygosity, for certain genetic disorders, such as homocystinuria, may result when low enzyme levels are detected in the lymphocytes of older people. PMID:6940198

  3. Overexpression of glucose-6-phosphate dehydrogenase enhances riboflavin production in Bacillus subtilis.

    PubMed

    Duan, Yun Xia; Chen, Tao; Chen, Xun; Zhao, Xue Ming

    2010-02-01

    Carbon flow in Bacillus subtilis through the pentose phosphate (PP) pathway was modulated by overexpression of glucose-6-phosphate dehydrogenase (G6PDH) under the control of the inducible Pxyl promoter in B. subtilis PY. Alteration of carbon flow into the PP pathway will affect the availability of ribulose-5-phosphate (Ru5P) and the riboflavin yield. Overexpression of G6PDH resulted in the glucose consumption rate increasing slightly, while the specific growth rate was unchanged. An improvement by 25% + or - 2 of the riboflavin production was obtained. Compared to by-products formation in flask culture, low acid production (acetate and pyruvate) and more acetoin were observed. Metabolic analysis, together with carbon flux redistribution, indicated that the PP pathway fluxes are increased in response to overexpression of G6PDH. Moreover, increased flux of the PP pathway is associated with an increased intracellular pool of Ru5P, which is a precursor for riboflavin biosynthesis. The high concentrations of Ru5P could explain the increased riboflavin production.

  4. The role of glucose-6-phosphate dehydrogenase in adipose tissue inflammation in obesity.

    PubMed

    Park, Yoon Jeong; Choe, Sung Sik; Sohn, Jee Hyung; Kim, Jae Bum

    2017-04-03

    Obesity is closely associated with metabolic diseases including type 2 diabetes. One hallmark characteristics of obesity is chronic inflammation that is coordinately controlled by complex signaling networks in adipose tissues. Compelling evidence indicates that reactive oxygen species (ROS) and its related signaling pathways play crucial roles in the progression of chronic inflammation in obesity. The pentose phosphate pathway (PPP) is an anabolic pathway that utilizes the glucoses to generate molecular building blocks and reducing equivalents in the form of NADPH. In particular, NADPH acts as one of the key modulators in the control of ROS through providing an electron for both ROS generation and scavenging. Recently, we have reported that glucose-6-phosphate dehydrogenase (G6PD), a rate-limiting enzyme of the PPP, is implicated in adipose tissue inflammation and systemic insulin resistance in obesity. Mechanistically, G6PD potentiates generation of ROS that augments pro-inflammatory responses in adipose tissue macrophages, leading to systemic insulin resistance. Here, we provide an overview of cell type- specific roles of G6PD in the regulation of ROS balance as well as additional details on the significance of G6PD that contributes to pro-oxidant NADPH generation in obesity-related chronic inflammation and insulin resistance.

  5. Control of glycolytic flux in Zymomonas mobilis by glucose 6-phosphate dehydrogenase activity

    SciTech Connect

    Snoep, J.L. |; Arfman, N.; Yomano, L.P.; Ingram, L.O.; Westerhoff, H.V.; Conway, T.

    1996-07-20

    Alycolytic genes in Zymomonas mobilis are highly expressed and constitute half of the cytoplasmic protein. The first four genes (glf, zwf, edd, glk) in this pathway form an operon encoding a glucose permease, glucose 6-phosphate dehydrogenase (G6-P dehydrogenase), 6-phosphogluconate dehydratase, and glucokinase, respectively. Each gene was overexpressed from a tac promoter to investigate the control of glycolysis during the early stages of batch fermentation when flux (qCO{sub 2}) is highest. Almost half of flux control appears to reside with G6-P dehydrogenase (C{sub G6-P dehydrogenase}{sup J} = 0.4). Although Z. mobilis exhibits one of the highest rates of glycolysis known, recombinants with elevated G6-P dehydrogenase had a 10% to 13% higher glycolytic flux than the native organism. A small increase in flux was also observed for recombinants expressing glf. Results obtained did not allow a critical evaluation of glucokinase and this enzyme may also represent an important control point. 6-Phosphogluconate dehydratase appears to be saturating at native levels. With constructs containing the full operon, growth rate and flux were both reduced, complicating interpretations. However, results obtained were also consistent with G6-P dehydrogenase as a primary site of control. Flux was 17% higher in operon constructs which exhibited a 17% increase in G6-P dehydrogenase specific activity, relative to the average of other operon constructs which contain a frameshift mutation in zwf.

  6. Glucose-6-Phosphate Dehydrogenase Deficiency Improves Insulin Resistance With Reduced Adipose Tissue Inflammation in Obesity.

    PubMed

    Ham, Mira; Choe, Sung Sik; Shin, Kyung Cheul; Choi, Goun; Kim, Ji-Won; Noh, Jung-Ran; Kim, Yong-Hoon; Ryu, Je-Won; Yoon, Kun-Ho; Lee, Chul-Ho; Kim, Jae Bum

    2016-09-01

    Glucose-6-phosphate dehydrogenase (G6PD), a rate-limiting enzyme of the pentose phosphate pathway, plays important roles in redox regulation and de novo lipogenesis. It was recently demonstrated that aberrant upregulation of G6PD in obese adipose tissue mediates insulin resistance as a result of imbalanced energy metabolism and oxidative stress. It remains elusive, however, whether inhibition of G6PD in vivo may relieve obesity-induced insulin resistance. In this study we showed that a hematopoietic G6PD defect alleviates insulin resistance in obesity, accompanied by reduced adipose tissue inflammation. Compared with wild-type littermates, G6PD-deficient mutant (G6PD(mut)) mice were glucose tolerant upon high-fat-diet (HFD) feeding. Intriguingly, the expression of NADPH oxidase genes to produce reactive oxygen species was alleviated, whereas that of antioxidant genes was enhanced in the adipose tissue of HFD-fed G6PD(mut) mice. In diet-induced obesity (DIO), the adipose tissue of G6PD(mut) mice decreased the expression of inflammatory cytokines, accompanied by downregulated proinflammatory macrophages. Accordingly, macrophages from G6PD(mut) mice greatly suppressed lipopolysaccharide-induced proinflammatory signaling cascades, leading to enhanced insulin sensitivity in adipocytes and hepatocytes. Furthermore, adoptive transfer of G6PD(mut) bone marrow to wild-type mice attenuated adipose tissue inflammation and improved glucose tolerance in DIO. Collectively, these data suggest that inhibition of macrophage G6PD would ameliorate insulin resistance in obesity through suppression of proinflammatory responses. © 2016 by the American Diabetes Association.

  7. Endothelial inflammation induced by excess glucose is associated with cytosolic glucose-6-phosphate but not increased mitochondrial respiration

    PubMed Central

    Sweet, Ian R; Gilbert, Merle; Maloney, Ezekiel; Hockenbery, David M.; Schwartz, Michael W.; Kim, Francis

    2009-01-01

    Aims/hypothesis Exposure of endothelial cells to high glucose levels suppresses responses to insulin, including induction of endothelial nitric oxide synthetase activity, through pro-inflammatory signaling via the IKKβ-NF-κB pathway. In the current study, we aimed to identify metabolic responses to glucose excess that mediate endothelial cell inflammation and insulin resistance. Since endothelial cells decrease their rate of oxygen consumption (OCR) in response to glucose, we hypothesized that increased mitochondrial function would not mediate these cell’s response to excess substrate. Methods The effects of glycolytic and mitochondrial fuels on metabolic intermediates and end products of glycolytic and oxidative metabolism, including glucose-6 phosphate (G6P), lactate, CO2, NAD(P)H, and OCR, were measured in cultured human microvascular endothelial cells and correlated with IKKβ activation. Results In response to increases in glucose concentration from low to physiological levels (0 to 5 mM), production of G6P, lactate, NAD(P)H and CO2 each increased as expected, while OCR was sharply reduced. IKKβ activation was detected at glucose concentrations above 5 mM, which was associated with parallel increases of G6P levels, whereas downstream metabolic pathways were insensitive to excess substrate. Conclusions/interpretation Activation of IKKβ by excess glucose correlates with increased levels of the glycolytic intermediate G6P, but not with lactate generation or OCR, which are inhibited well below saturation levels at physiologic glucose concentrations. These findings suggest that oxidative stress due to increased mitochondrial respiration is unlikely to mediate endothelial inflammation induced by excess glucose and suggests instead the involvement of G6P accumulation in the adverse effects of hyperglycemia on endothelial cells. PMID:19219423

  8. Detection of Occult Acute Kidney Injury in Glucose-6-Phosphate Dehydrogenase Deficiency Anemia

    PubMed Central

    Abdel Hakeem, Gehan Lotfy; Abdel Naeem, Emad Allam; Swelam, Salwa Hussein; El Morsi Aboul Fotoh, Laila; El Mazary, Abdel Azeem Mohamed; Abdel Fadil, Ashraf Mohamed; Abdel Hafez, Asmaa Hosny

    2016-01-01

    Background Glucose-6-phosphate dehydrogenase (G6PD) deficiency anemia is associated with intravascular hemolysis. The freely filtered hemoglobin can damage the kidney. We aimed to assess any subclinical renal injury in G6PD children. Methods Sixty children were included. Thirty G6PD deficiency anemia children were enrolled during the acute hemolytic crisis and after the hemolytic episode had elapsed. Another thirty healthy children were included as controls. Serum cystatin C, creatinine levels, and urinary albumin/creatinine (A/C) ratio were measured, and the glomerular filtration rate (GFR) was calculated. Results Significantly higher urinary A/C ratio (p=0.001,0.002 respectively) and lower GFR (p=0.001 for both) were found during hemolysis and after the hemolytic episode compared to the controls. Also, significant higher serum cystatin C (p=0.001), creatinine (p=0.05) and A/C (p= 0.001) ratio and insignificant lower GFR (p=0.3) during acute hemolytic crisis compared to the same children after the hemolytic episode subsided. Conclusions G6PD deficiency anemia is associated with a variable degree of acute renal injury during acute hemolytic episodes which may persist after elapsing of the hemolytic crises. PMID:27648201

  9. A hemolysis trigger in glucose-6-phosphate dehydrogenase enzyme deficiency. Vicia sativa (Vetch).

    PubMed

    Bicakci, Zafer

    2009-02-01

    Glucose-6-phosphate dehydrogenase (G6PD) is an enzyme, playing an important role in the redox metabolism of all aerobic cells. It was reported that certain medications, fava beans, and infections can trigger acute hemolytic anemia in patients with G6PD deficiency. An 8-year-old male patient was admitted to the hospital with blood in the urine, headache, dizziness, fatigue, loss of appetite, and jaundice in the eyes, 24 hours after eating large amounts of fresh, vetch grains. Laboratory investigation revealed hemolytic anemia, hyperbilirubinemia, and G6PD deficiency. Approximately 0.5% of fava bean seeds have 2 pyrimidine beta-glycosides called, vicine and convicine. Vetch has 0.731% vicine, 0.081% convicine, and 0.530% beta cyanoalanine glycosides. The aim of this case report is to emphasize the importance of vetch seeds as a cause for hemolytic crisis in our country, where approximately one million tons of vetch is produced per year, especially in the agricultural regions.

  10. Incidence and mutation analysis of glucose-6-phosphate dehydrogenase deficiency in eastern Indonesian populations.

    PubMed

    Tantular, Indah S; Matsuoka, Hiroyuki; Kasahara, Yuichi; Pusarawati, Suhintam; Kanbe, Toshio; Tuda, Josef S B; Kido, Yasutoshi; Dachlan, Yoes P; Kawamoto, Fumihiko

    2010-12-01

    We conducted a field survey of glucose-6-phosphate dehydrogenese (G6PD) deficiency in the eastern Indonesian islands, and analyzed G6PD variants molecularly. The incidence of G6PD deficiency in 5 ethnic groups (Manggarai, Bajawa, Nage-Keo, Larantuka, and Palue) on the Flores and Palue Islands was lower than that of another native group, Sikka, or a nonnative group, Riung. Molecular analysis of G6PD variants indicated that 19 cases in Sikka had a frequency distribution of G6PD variants similar to those in our previous studies, while 8 cases in Riung had a different frequency distribution of G6PD variants. On the other hand, from field surveys in another 8 ethnic groups (Timorese, Sumbanese, Savunese, Kendari, Buton, Muna, Minahasa, and Sangirese) on the islands of West Timor, Sumba, Sulawesi, Muna and Bangka, a total of 49 deficient cases were detected. Thirty-nine of these 49 cases had G6PD Vanua Lava (383T>C) of Melanesian origin. In our previous studies, many cases of G6PD Vanua Lava were found on other eastern Indonesian islands. Taken together, these findings may indicate that G6PD Vanua Lava is the most common variant in eastern Indonesian populations, except for Sikka.

  11. Comparison of quantitative and qualitative tests for glucose-6-phosphate dehydrogenase deficiency in the neonatal period.

    PubMed

    Keihanian, F; Basirjafari, S; Darbandi, B; Saeidinia, A; Jafroodi, M; Sharafi, R; Shakiba, M

    2017-06-01

    Considering the high prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency among newborns, different screening methods have been established in various countries. In this study, we aimed to assess the prevalence of G6PD deficiency among newborns in Rasht, Iran, and compare G6PD activity in cord blood samples, using quantitative and qualitative tests. This cross-sectional, prospective study was performed at five largest hospitals in Rasht, Guilan Province, Iran. The screening tests were performed for all the newborns, referred to these hospitals. Specimens were characterized in terms of G6PD activity under ultraviolet light, using the kinetic method and the qualitative fluorescent spot test (FST). We also determined the sensitivity, specificity, negative predictive value, and positive predictive value of the qualitative assay. Blood samples were collected from 1474 newborns. Overall, 757 (51.4%) subjects were male. As the findings revealed, 1376 (93.4%) newborns showed normal G6PD activity, while 98 (6.6%) had G6PD deficiency. There was a significant difference in the mean G6PD level between males and females (P = 0.0001). Also, a significant relationship was detected between FST results and the mean values obtained in the quantitative test (P < 0.0001). According to the present study, FST showed acceptable sensitivity and specificity for G6PD activity, although it appeared inefficient for diagnostic purposes in some cases. © 2017 John Wiley & Sons Ltd.

  12. Multiple Independent Fusions of Glucose-6-Phosphate Dehydrogenase with Enzymes in the Pentose Phosphate Pathway

    PubMed Central

    Stover, Nicholas A.; Dixon, Thomas A.; Cavalcanti, Andre R. O.

    2011-01-01

    Fusions of the first two enzymes in the pentose phosphate pathway, glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconolactonase (6PGL), have been previously described in two distant clades, chordates and species of the malarial parasite Plasmodium. We have analyzed genome and expressed sequence data from a variety of organisms to identify the origins of these gene fusion events. Based on the orientation of the domains and range of species in which homologs can be found, the fusions appear to have occurred independently, near the base of the metazoan and apicomplexan lineages. Only one of the two metazoan paralogs of G6PD is fused, showing that the fusion occurred after a duplication event, which we have traced back to an ancestor of choanoflagellates and metazoans. The Plasmodium genes are known to contain a functionally important insertion that is not seen in the other apicomplexan fusions, highlighting this as a unique characteristic of this group. Surprisingly, our search revealed two additional fusion events, one that combined 6PGL and G6PD in an ancestor of the protozoan parasites Trichomonas and Giardia, and another fusing G6PD with phosphogluconate dehydrogenase (6PGD) in a species of diatoms. This study extends the range of species known to contain fusions in the pentose phosphate pathway to many new medically and economically important organisms. PMID:21829610

  13. Aldosterone impairs vascular reactivity by decreasing glucose-6-phosphate dehydrogenase activity

    PubMed Central

    Leopold, Jane A.; Dam, Aamir; Maron, Bradley A.; Scribner, Anne W.; Liao, Ronglih; Handy, Diane E.; Stanton, Robert C.; Pitt, Bertram; Loscalzo, Joseph

    2013-01-01

    Hyperaldosteronism is associated with impaired vascular reactivity; however, the mechanism by which aldosterone promotes endothelial dysfunction remains unknown. Glucose-6-phosphate dehydrogenase (G6pd), the principal source of Nadph, modulates vascular function by limiting oxidant stress to preserve bioavailable nitric oxide (NO•). In these studies, we show that aldosterone (10−9-10−7 mol/l) decreases endothelial G6pd expression and activity in vitro resulting in increased oxidant stress and decreased cGMP levels similar to what is observed in G6pd-deficient cells. Aldosterone decreases G6pd expression by protein kinase A activation to increase expression of Crem, which interferes with Creb binding to the G6pd promoter. In vivo, infusion of aldosterone decreases vascular G6pd expression and impairs vascular reactivity. These effects are abrogated by spironolactone or vascular gene transfer of G6pd. These studies demonstrate that aldosterone induces a G6pd-deficient phenotype to impair endothelial function; aldosterone antagonism or gene transfer of G6pd improves vascular reactivity by restoring G6pd activity. PMID:17273168

  14. Molecular characterization of a German variant of glucose-6-phosphate dehydrogenase deficiency (G6PD Aachen).

    PubMed

    Efferth, T; Osieka, R; Beutler, E

    2000-02-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-chromosome-linked hereditary disorder. Clinically, patients with G6PD deficiency often present with drug- or food-induced hemolytic crises or neonatal jaundice. G6PD is involved in the generation of NADPH and reduced glutathione. In contrast to American, Mediterranean, and African ancestries, only few variants are known from Middle and Northern Europe. We describe the molecular characterization of a distinct variant from the northwestern area of Germany, G6PD Aachen. The sequence of the G6PD gene from three afflicted males was found to be hemizygous at cDNA residue 1089 for a C-->G mutation with a predicted amino acid change of Asn363Lys. The 1089 C-->G point mutation is unique, but produces the identical amino acid change found in a Mexican variant of G6PD deficiency, G6PD Loma Linda. This G6PD-deficient variant is caused by a 1089 C-->A mutation. The 363-amino-acid replacement is located outside a known mutation cluster region between amino acid residues 380 and 450, but may disrupt or weaken dimer interactions of G6PD enzyme subunits.

  15. [Glucose 6-phosphate dehydrogenase deficiency: a protection against malaria and a risk for hemolytic accidents].

    PubMed

    Wajcman, Henri; Galactéros, Frédéric

    2004-08-01

    Glucose 6-phosphate dehydrogenase (G6PD) catalyses the first step of the pentose phosphate pathway, which in the RBC leads to the formation of NADPH, essential to prevent the cell from an oxidative stress. Worldwide, more than 400 million people (90% being males) are affected by G6PD deficiency, in regions that are, or have been, endemic for malaria and in populations originating from these regions. RBCs with low G6PD activity offer a hostile environment to parasite growth and thus an advantage to G6PD deficiency carriers. The counterpart of this protective effect is an increased susceptibility to oxidants such as some foods (fava beans), drugs (anti-malarial or sulphonamides), or various chemicals. In the case of G6PD deficiency, the hypothesis of a convergent evolution between parasite, protecting mutation, and cultural traditions (food, skin painting...) has been proposed. Near to 150 different G6PD variants have been described, which are classified into four types, according to their clinical effects. Several variants, such as the G6PD A- or the Mediterranean variant, reach the polymorphism level in endemic regions. The recent determination of the three-dimensional structure of this enzyme allows one to explain now the mechanisms of the disorders in terms of structure-function relationship.

  16. Glucose-6-Phosphate Dehydrogenase-Deficiency in Transfusion Medicine: The Unknown Risks

    PubMed Central

    Francis, Richard O.; Jhang, Jeffrey S.; Pham, Huy P.; Hod, Eldad A.; Zimring, James C.; Spitalnik, Steven L.

    2013-01-01

    The hallmark of glucose-6-phosphate dehydrogenase (G6PD) deficiency is red blood cell (RBC) destruction in response to oxidative stress. Patients requiring RBC transfusions may simultaneously receive oxidative medications or have concurrent infections, both of which can induce hemolysis in G6PD-deficient RBCs. Although it is not routine practice to screen healthy blood donors for G6PD deficiency, case reports identified transfusion of G6PD-deficient RBCs as causing hemolysis and other adverse events. In addition, some patient populations may be more at risk for complications associated with transfusions of G6PD-deficient RBCs because they receive RBCs from donors who are more likely to have G6PD deficiency. This review discusses G6PD deficiency, its importance in transfusion medicine, changes in the RBC antioxidant system (of which G6PD is essential) during refrigerated storage, and mechanisms of hemolysis. In addition, as yet unanswered questions that could be addressed by translational and clinical studies are identified and discussed. PMID:23815264

  17. Testis-specific expression of a functional retroposon encoding glucose-6-phosphate dehydrogenase in the mouse

    SciTech Connect

    Hendriksen, P.J.M. |; Hoogerbrugge, J.W.; Baarends, W.M.

    1997-05-01

    The X-chromosomal gene glucose-6-phosphate dehydrogenase (G6pd) is known to be expressed in most cell types of mammalian species. In the mouse, we have detected a novel gene, designated G6pd-2, encoding a G6PD isoenzyme. G6pd-2 does not contain introns and appears to represent a retroposed gene. This gene is uniquely transcribed in postmeiotic spermatogenic cells in which the X-encoded G6pd gene is not transcribed. Expression of the G6pd-2 sequence in a bacterial system showed that the encoded product is an active enzyme. Zymogramic analysis demonstrated that recombinant G6PD-2, but not recombinant G6PD-1 (the X-chromosome-encoded G6PD), formed tetramers under reducing conditions. Under the same conditions, G6PD tetramers were also found in extracts of spermatids and spermatozoa, indicating the presence of G6pd-2-encoded isoenzyme in these cell types. G6pd-2 is one of the very few known expressed retroposons encoding a functional protein, and the presence of this gene is probably related to X chromosome inactivation during spermatogenesis. 62 refs., 7 figs.

  18. Nitrogen Assimilation, Abiotic Stress and Glucose 6-Phosphate Dehydrogenase: The Full Circle of Reductants

    PubMed Central

    Esposito, Sergio

    2016-01-01

    Glucose 6 phosphate dehydrogenase (G6PDH; EC 1.1.1.49) is well-known as the main regulatory enzyme of the oxidative pentose phosphate pathway (OPPP) in living organisms. Namely, in Planta, different G6PDH isoforms may occur, generally localized in cytosol and plastids/chloroplasts. These enzymes are differently regulated by distinct mechanisms, still far from being defined in detail. In the last decades, a pivotal function for plant G6PDHs during the assimilation of nitrogen, providing reductants for enzymes involved in nitrate reduction and ammonium assimilation, has been described. More recently, several studies have suggested a main role of G6PDH to counteract different stress conditions, among these salinity and drought, with the involvement of an ABA depending signal. In the last few years, this recognized vision has been greatly widened, due to studies clearly showing the non-conventional subcellular localization of the different G6PDHs, and the peculiar regulation of the different isoforms. The whole body of these considerations suggests a central question: how do the plant cells distribute the reductants coming from G6PDH and balance their equilibrium? This review explores the present knowledge about these mechanisms, in order to propose a scheme of distribution of reductants produced by G6PDH during nitrogen assimilation and stress. PMID:27187489

  19. Splenic artery pseudoaneurysm due to seatbelt injury in a glucose-6-phosphate dehydrogenase-deficient adult.

    PubMed

    Lau, Yu Zhen; Lau, Yuk Fai; Lai, Kang Yiu; Lau, Chu Pak

    2013-11-01

    A 23-year-old man presented with abdominal pain after suffering blunt trauma caused by a seatbelt injury. His low platelet count of 137 × 10(9)/L was initially attributed to trauma and his underlying hypersplenism due to glucose-6-phosphate dehydrogenase (G6PD) deficiency. Despite conservative management, his platelet count remained persistently reduced even after his haemoglobin and clotting abnormalities were stabilised. After a week, follow-up imaging revealed an incidental finding of a pseudoaneurysm (measuring 9 mm × 8 mm × 10 mm) adjacent to a splenic laceration. The pseudoaneurysm was successfully closed via transcatheter glue embolisation; 20% of the spleen was also embolised. A week later, the platelet count normalised, and the patient was subsequently discharged. This case highlights the pitfalls in the detection of a delayed occurrence of splenic artery pseudoaneurysm after blunt injury via routine delayed phase computed tomography. While splenomegaly in G6PD may be a predisposing factor for injury, a low platelet count should arouse suspicion of internal haemorrhage rather than hypersplenism.

  20. Comparison of quantitative and qualitative tests for glucose-6-phosphate dehydrogenase deficiency.

    PubMed

    LaRue, Nicole; Kahn, Maria; Murray, Marjorie; Leader, Brandon T; Bansil, Pooja; McGray, Sarah; Kalnoky, Michael; Zhang, Hao; Huang, Huiqiang; Jiang, Hui; Domingo, Gonzalo J

    2014-10-01

    A barrier to eliminating Plasmodium vivax malaria is inadequate treatment of infected patients. 8-Aminoquinoline-based drugs clear the parasite; however, people with glucose-6-phosphate dehydrogenase (G6PD) deficiency are at risk for hemolysis from these drugs. Understanding the performance of G6PD deficiency tests is critical for patient safety. Two quantitative assays and two qualitative tests were evaluated. The comparison of quantitative assays gave a Pearson correlation coefficient of 0.7585 with significant difference in mean G6PD activity, highlighting the need to adhere to a single reference assay. Both qualitative tests had high sensitivity and negative predictive value at a cutoff G6PD value of 40% of normal activity if interpreted conservatively and performed under laboratory conditions. The performance of both tests dropped at a cutoff level of 45%. Cytochemical staining of specimens confirmed that heterozygous females with > 50% G6PD-deficient cells can seem normal by phenotypic tests. © The American Society of Tropical Medicine and Hygiene.

  1. Haemoglobinopathies, glucose-6-phosphate dehydrogenase deficiency and allied problems in the Indian subcontinent

    PubMed Central

    Chatterjea, J. B.

    1966-01-01

    The present world-wide interest in haemoglobinopathies and allied disorders has given rise to a very considerable literature over the past two decades. This communication reviews this literature in so far as it refers to the Indian subcontinent. The most common abnormality is thalassaemia, which has been discovered in all regions under consideration: India, Pakistan, Nepal, Bhutan and Ceylon. Haemoglobins S, D and E are also quite common: Hb S has been found mostly in the aboriginal tribes, Hb D in Gujaratis and Punjabis and Hb E in Bengalis, Assamese and Nepalese. A few instances of haemoglobins F, H, J, K, L and M have also been reported. However, there remain many population groups to be investigated. Studies of the distribution of glucose-6-phosphate dehydrogenase deficiency are also reviewed, and the correlation between the various haemoglobin disorders and various environmental factors is discussed, but it is pointed out that the relevant data are still insufficient to allow any definite conclusions to be drawn. PMID:5338376

  2. Glucose-6-Phosphate Dehydrogenase: Update and Analysis of New Mutations around the World

    PubMed Central

    Gómez-Manzo, Saúl; Marcial-Quino, Jaime; Vanoye-Carlo, America; Serrano-Posada, Hugo; Ortega-Cuellar, Daniel; González-Valdez, Abigail; Castillo-Rodríguez, Rosa Angélica; Hernández-Ochoa, Beatriz; Sierra-Palacios, Edgar; Rodríguez-Bustamante, Eduardo; Arreguin-Espinosa, Roberto

    2016-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) is a key regulatory enzyme in the pentose phosphate pathway which produces nicotinamide adenine dinucleotide phosphate (NADPH) to maintain an adequate reducing environment in the cells and is especially important in red blood cells (RBC). Given its central role in the regulation of redox state, it is understandable that mutations in the gene encoding G6PD can cause deficiency of the protein activity leading to clinical manifestations such as neonatal jaundice and acute hemolytic anemia. Recently, an extensive review has been published about variants in the g6pd gene; recognizing 186 mutations. In this work, we review the state of the art in G6PD deficiency, describing 217 mutations in the g6pd gene; we also compile information about 31 new mutations, 16 that were not recognized and 15 more that have recently been reported. In order to get a better picture of the effects of new described mutations in g6pd gene, we locate the point mutations in the solved three-dimensional structure of the human G6PD protein. We found that class I mutations have the most deleterious effects on the structure and stability of the protein. PMID:27941691

  3. Glucose-6-Phosphate Dehydrogenase: Update and Analysis of New Mutations around the World.

    PubMed

    Gómez-Manzo, Saúl; Marcial-Quino, Jaime; Vanoye-Carlo, America; Serrano-Posada, Hugo; Ortega-Cuellar, Daniel; González-Valdez, Abigail; Castillo-Rodríguez, Rosa Angélica; Hernández-Ochoa, Beatriz; Sierra-Palacios, Edgar; Rodríguez-Bustamante, Eduardo; Arreguin-Espinosa, Roberto

    2016-12-09

    Glucose-6-phosphate dehydrogenase (G6PD) is a key regulatory enzyme in the pentose phosphate pathway which produces nicotinamide adenine dinucleotide phosphate (NADPH) to maintain an adequate reducing environment in the cells and is especially important in red blood cells (RBC). Given its central role in the regulation of redox state, it is understandable that mutations in the gene encoding G6PD can cause deficiency of the protein activity leading to clinical manifestations such as neonatal jaundice and acute hemolytic anemia. Recently, an extensive review has been published about variants in the g6pd gene; recognizing 186 mutations. In this work, we review the state of the art in G6PD deficiency, describing 217 mutations in the g6pd gene; we also compile information about 31 new mutations, 16 that were not recognized and 15 more that have recently been reported. In order to get a better picture of the effects of new described mutations in g6pd gene, we locate the point mutations in the solved three-dimensional structure of the human G6PD protein. We found that class I mutations have the most deleterious effects on the structure and stability of the protein.

  4. Enhanced expression of glucose-6-phosphate dehydrogenase in human cells sustaining oxidative stress.

    PubMed Central

    Ursini, M V; Parrella, A; Rosa, G; Salzano, S; Martini, G

    1997-01-01

    Recent reports have demonstrated that glucose-6-phosphate dehydrogenase (G6PD) activity in mammalian cells is necessary in order to ensure cell survival when damage is produced by reactive oxygen intermediates. In this paper we demonstrate that oxidative stress, caused by agents acting at different steps in the biochemical pathway controlling the intracellular redox status, determines the increase in G6PD-specific activity in human cell lines of different tissue origins. The intracellular level of G6PD-specific mRNA also increases, with kinetics compatible with the induction of new enzyme synthesis. We carried out experiments in which cells were exposed to oxidative stress in the presence of inhibitors of protein or RNA synthesis. These demonstrated that increased G6PD expression is mainly due to an increased rate of transcription, with a minor but significant contribution of regulatory mechanisms acting at post-transcriptional levels. These results provide new information on the defence systems that eukaryotic cells possess in order to prevent damage caused by potentially harmful oxygen derivatives. PMID:9169615

  5. New PCR Assay Using Glucose-6-Phosphate Dehydrogenase for Identification of Leishmania Species

    PubMed Central

    Castilho, Tiago M.; Shaw, Jeffrey Jon; Floeter-Winter, Lucile M.

    2003-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) is one of the multilocus enzymes used to identify Leishmania by zymodeme analysis. The polymorphic pattern revealed by partial characterization of the gene encoding G6PD generated molecular markers useful in the identification of different Leishmania species by PCR. Initially degenerate oligonucleotides were designed on the basis of data on the conserved active center described for other organisms. Primers for reverse transcription-PCR experiments, designed from the nucleotide sequence of the PCR product, enabled us to characterize the 5′ and 3′ untranslated regions and the G6PD open reading frame of reference strains of Leishmania (Viannia) braziliensis, Leishmania (Viannia) guyanensis, Leishmania (Leishmania) mexicana, and Leishmania (Leishmania) amazonensis. Sets of paired primers were designed and used in PCR assays to discriminate between the parasites responsible for tegumentar leishmaniasis of the subgenera Leishmania (Leishmania) and Leishmania (Viannia) and to distinguish L. (Viannia) braziliensis from others organisms of the subgenus Leishmania (Viannia). No amplification products were detected for the DNA of Crithidia fasciculata, Trypanosoma cruzi, or Leishmania (Sauroleishmania) tarentolae or DNA from a healthy human control. The tests proved to be specific and were sensitive enough to detect parasites in human biopsy specimens. The successful discrimination of L. (Viannia) braziliensis from other parasites of the subgenus Leishmania (Viannia) opens the way to epidemiological studies in areas where more than one species of the subgenus Leishmania (Viannia) exist, such as Amazonia, as well as follow-up studies after chemotherapy and assessment of clinical prognoses. PMID:12574243

  6. Glucose-6-phosphate dehydrogenase deficiency and risk of diabetes: a systematic review and meta-analysis.

    PubMed

    Lai, Yin Key; Lai, Nai Ming; Lee, Shaun Wen Huey

    2017-05-01

    Emerging epidemiological evidence suggests that patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency may have a higher risk of developing diabetes. The aim of the review was to synthesise the evidence on the association between G6PD deficiency and diabetes. A systematic search on Medline, EMBASE, AMED and CENTRAL databases for studies published between January 1966 and September 2016 that assessed the association between G6PD deficiency and diabetes was conducted. This was supplemented by a review of the reference list of retrieved articles. We extracted data on study characteristics, outcomes and performed an assessment on the methodological quality of the studies. A random-effects model was used to compute the summary risk estimates. Fifteen relevant publications involving 949,260 participants were identified, from which seven studies contributed to the meta-analysis. G6PD deficiency was associated with a higher odd of diabetes (odds ratio 2.37, 95% confidence interval 1.50-3.73). The odds ratio of diabetes among men was higher (2.22, 1.31-3.75) compared to women (1.87, 1.12-3.12). This association was broadly consistent in the sensitivity analysis. Current evidence suggests that G6PD deficiency may be a risk factor for diabetes, with higher odds among men compared to women. Further research is needed to determine how G6PD deficiency moderates diabetes.

  7. Glucose-6-phosphate dehydrogenase deficiency in northern Mexico and description of a novel mutation.

    PubMed

    García-Magallanes, N; Luque-Ortega, F; Aguilar-Medina, E M; Ramos-Payán, R; Galaviz-Hernández, C; Romero-Quintana, J G; Del Pozo-Yauner, L; Rangel-Villalobos, H; Arámbula-Meraz, E

    2014-08-01

    Glucose-6-phosphate dehydrogenase deficiency (G6PD) is the most common enzyme pathology in humans; it is X-linked inherited and causes neonatal hyperbilirubinaemia, chronic nonspherocytic haemolytic anaemia and drug-induced acute haemolytic anaemia. G6PD deficiency has scarcely been studied in the northern region of Mexico, which is important because of the genetic heterogeneity described in Mexican population. Therefore, samples from the northern Mexico were biochemically screened for G6PD deficiency, and PCR-RFLPs, and DNA sequencing used to identify mutations in positive samples. The frequency of G6PD deficiency in the population was 0.95% (n = 1993); the mutations in 86% of these samples were G6PD A(-202A/376G), G6PDA(-376G/968C) and G6PD Santamaria(376G/542T). Contrary to previous reports, we demonstrated that G6PD deficiency distribution is relatively homogenous throughout the country (P = 0.48336), and the unique exception with high frequency of G6PD deficiency does not involve a coastal population (Chihuahua: 2.4%). Analysis of eight polymorphic sites showed only 10 haplotypes. In one individual we identified a new G6PD mutation named Mexico DF(193A>G) (rs199474830), which probably results in a damaging functional effect, according to PolyPhen analysis. Proteomic impact of the mutation is also described.

  8. Glucose-6-phosphate dehydrogenase deficiency A- variant in febrile patients in Haiti.

    PubMed

    Carter, Tamar E; Maloy, Halley; von Fricken, Michael; St Victor, Yves; Romain, Jean R; Okech, Bernard A; Mulligan, Connie J

    2014-08-01

    Haiti is one of two remaining malaria-endemic countries in the Caribbean. To decrease malaria transmission in Haiti, primaquine was recently added to the malaria treatment public health policy. One limitation of primaquine is that, at certain doses, primaquine can cause hemolytic anemia in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency (G6PDd). In this study, we genotyped two mutations (A376G and G202A), which confer the most common G6PDd variant in West African populations, G6PDd A-. We estimated the frequency of G6PDd A- in a sample of febrile patients enrolled in an on-going malaria study who represent a potential target population for a primaquine mass drug administration. We found that 33 of 168 individuals carried the G6PDd A- allele (includes A- hemizygous males, A- homozygous or heterozygous females) and could experience toxicity if treated with primaquine. These data inform discussions on safe and effective primaquine dosing and future malaria elimination strategies for Haiti.

  9. Glucose-6-phosphate dehydrogenase deficiency (G6PD) as a risk factor of male neonatal sepsis.

    PubMed

    Rostami-Far, Z; Ghadiri, K; Rostami-Far, M; Shaveisi-Zadeh, F; Amiri, A; Rahimian Zarif, B

    2016-01-01

    Introduction.Neonatal sepsis is a disease process, which represents the systemic response of bacteria entering the bloodstream during the first 28 days of life. The prevalence of sepsis is higher in male infants than in females, but the exact cause is unknown. Glucose-6-phosphate dehydrogenase (G6PD) is an enzyme in the pentose phosphate pathway, which leads to the production of NADPH. NADPH is required for the respiratory burst reaction in white blood cells (WBCs) to destroy microorganisms. The purpose of this study was to evaluate the prevalence of G6PD deficiency in neonates with sepsis. Materials and methods.This study was performed on 76 neonates with sepsis and 1214 normal neonates from February 2012 to November 2014 in the west of Iran. The G6PD deficiency status was determined by fluorescent spot test. WBCs number and neutrophils percentages were measured and compared in patients with and without G6PD deficiency. Results.The prevalence of the G6PD deficiency in neonates with sepsis was significantly higher compared to the control group (p=0.03). WBCs number and neutrophils percentages in G6PD deficient patients compared with patients without G6PD deficiency were decreased, but were not statistically significant (p=0.77 and p=0.86 respectively). Conclusions.G6PD deficiency is a risk factor of neonatal sepsis and also a justification for more male involvement in this disease. Therefore, newborn screening for this disorder is recommended.

  10. Anemia in patients with coinherited thalassemia and glucose-6-phosphate dehydrogenase deficiency.

    PubMed

    Pornprasert, Sakorn; Phanthong, Siratcha

    2013-01-01

    Thalassemia and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency are genetic disorders that cause hemolytic anemia. In areas with high frequencies of both hematological disorders, coinheritance of G-6-PD deficiency with thalassemia can be found. Whether G-6-PD deficiency, coinherited with thalassemia, enhances severe anemia is still unclear. Hematological parameters between thalassemia carriers with G-6-PD deficiency and those without G-6-PD deficiency were compared. The G-6-PD deficiency was diagnosed in 410 blood samples from thalassemia patients using a fluorescent spot test. The levels of hemoglobin (Hb), packed cell volume (PCV), mean corpuscular volume (MCV) and Hb A2/Hb E [β26(B8)Glu→Lys; HBB: c.79G>A] were measured using an automated blood counter and high performance liquid chromatography (HPLC), respectively. The G-6-PD deficiency was found in 37 samples (9.02%). Mean levels of Hb, PCV, MCV and Hb A2/E were similar between the two groups. Thus, G-6-PD deficiency did not enhance red blood cell pathology or induce more anemic severity in thalassemia patients.

  11. Glucose-6-phosphate dehydrogenase (G6PD) deficiency among tribal populations of India - Country scenario.

    PubMed

    Mukherjee, Malay B; Colah, Roshan B; Martin, Snehal; Ghosh, Kanjaksha

    2015-05-01

    It is believed that the tribal people, who constitute 8.6 per cent of the total population (2011 census of India), are the original inhabitants of India. Glucose-6-phosphate-dehydrogenase (G6PD) deficiency is an X-linked genetic defect, affecting around 400 million people worldwide and is characterized by considerable biochemical and molecular heterogeneity. Deficiency of this enzyme is highly polymorphic in those areas where malaria is/has been endemic. G6PD deficiency was reported from India more than 50 years ago. t0 he prevalence varies from 2.3 to 27.0 per cent with an overall prevalence of 7.7 per cent in different tribal groups. Since the tribal populations live in remote areas where malaria is/has been endemic, irrational use of antimalarial drugs could result in an increased number of cases with drug induced haemolysis. Therefore, before giving antimalarial therapy, routine screening for G6PD deficiency should be undertaken in those tribal communities where its prevalence is high.

  12. Prevalence and molecular characterization of glucose-6-phosphate dehydrogenase deficiency in northern Thailand.

    PubMed

    Charoenkwan, Pimlak; Tantiprabha, Watcharee; Sirichotiyakul, Supatra; Phusua, Arunee; Sanguansermsri, Torpong

    2014-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common inherited enzymopathies in endemic areas of malaria including Southeast Asia. The molecular features of G6PD deficiency are similar among Southeast Asian population, with differences in the type of the prominent variants in each region. This study determined the prevalence and molecular characteristics of G6PD deficiency in northern Thailand. Quantitative assay of G6PD activity was conducted in 566 neonatal cord blood samples and 6 common G6PD mutations were determined by PCR-restriction fragment length polymorphism method on G6PD complete and intermediate deficiency samples. Ninety newborns had G6PD deficiency, with prevalence in male newborns of 17% and that of female newborns having an intermediate and complete deficiency of 13% and 2%, respectively. From 95 G6PD alleles tested, G6PD Mahidol, G6PD Kaiping, G6PD Canton, G6PD Viangchan, G6PD Union, and G6PD Chinese-5 was detected in 19, 17, 15, 13, 7, and 2 alleles, respectively. Our study shows that the prevalence of G6PD deficiency in northern Thai population is high and combination of the common Chinese mutations is the majority, a distribution different from central and southern Thailand where G6PD Viangchan is the prominent variant. These findings suggest a higher proportion of assimilated Chinese ethnic group in the northern Thai population.

  13. Glucose-6-phosphate dehydrogenase deficiency in transfusion medicine: the unknown risks.

    PubMed

    Francis, R O; Jhang, J S; Pham, H P; Hod, E A; Zimring, J C; Spitalnik, S L

    2013-11-01

    The hallmark of glucose-6-phosphate dehydrogenase (G6PD) deficiency is red blood cell (RBC) destruction in response to oxidative stress. Patients requiring RBC transfusions may simultaneously receive oxidative medications or have concurrent infections, both of which can induce haemolysis in G6PD-deficient RBCs. Although it is not routine practice to screen healthy blood donors for G6PD deficiency, case reports identified transfusion of G6PD-deficient RBCs as causing haemolysis and other adverse events. In addition, some patient populations may be more at risk for complications associated with transfusions of G6PD-deficient RBCs because they receive RBCs from donors who are more likely to have G6PD deficiency. This review discusses G6PD deficiency, its importance in transfusion medicine, changes in the RBC antioxidant system (of which G6PD is essential) during refrigerated storage and mechanisms of haemolysis. In addition, as yet unanswered questions that could be addressed by translational and clinical studies are identified and discussed.

  14. Neonatal screening for glucose-6-phosphate dehydrogenase deficiency: biochemical versus genetic technologies.

    PubMed

    Kaplan, Michael; Hammerman, Cathy

    2011-06-01

    Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency, a commonly occurring genetic condition, is associated in neonates with severe hemolytic episodes, extreme hyperbilirubinemia, and bilirubin encephalopathy. Neonatal screening programs for the condition should increase parental and caretaker awareness, thereby facilitating early access to treatment with resultant diminished mortality and morbidity. However, screening for G-6-PD deficiency is not widely performed. Although G-6-PD-deficient males may be accurately identified, females are more difficult to categorize because many in this group may be heterozygotes with phenotype overlap between normal homozygotes, heterozygotes, and deficient homozygotes. Screening methodologies include biochemical qualitative assays, quantitative enzymatic activity measurements and DNA-based polymerase chain reaction molecular screening. The appropriateness of any of these technologies for any particular population group or geographic area must be assessed before setting up a screening program. The pros and cons of each method, including ease of testing, cost, need for sophisticated laboratory equipment and degree of personnel training, as well as the ability to identify females, are discussed.

  15. Nitrogen Assimilation, Abiotic Stress and Glucose 6-Phosphate Dehydrogenase: The Full Circle of Reductants.

    PubMed

    Esposito, Sergio

    2016-05-11

    Glucose 6 phosphate dehydrogenase (G6PDH; EC 1.1.1.49) is well-known as the main regulatory enzyme of the oxidative pentose phosphate pathway (OPPP) in living organisms. Namely, in Planta, different G6PDH isoforms may occur, generally localized in cytosol and plastids/chloroplasts. These enzymes are differently regulated by distinct mechanisms, still far from being defined in detail. In the last decades, a pivotal function for plant G6PDHs during the assimilation of nitrogen, providing reductants for enzymes involved in nitrate reduction and ammonium assimilation, has been described. More recently, several studies have suggested a main role of G6PDH to counteract different stress conditions, among these salinity and drought, with the involvement of an ABA depending signal. In the last few years, this recognized vision has been greatly widened, due to studies clearly showing the non-conventional subcellular localization of the different G6PDHs, and the peculiar regulation of the different isoforms. The whole body of these considerations suggests a central question: how do the plant cells distribute the reductants coming from G6PDH and balance their equilibrium? This review explores the present knowledge about these mechanisms, in order to propose a scheme of distribution of reductants produced by G6PDH during nitrogen assimilation and stress.

  16. Humanized mouse model of glucose 6-phosphate dehydrogenase deficiency for in vivo assessment of hemolytic toxicity.

    PubMed

    Rochford, Rosemary; Ohrt, Colin; Baresel, Paul C; Campo, Brice; Sampath, Aruna; Magill, Alan J; Tekwani, Babu L; Walker, Larry A

    2013-10-22

    Individuals with glucose 6-phosphate dehydrogenase (G6PD) deficiency are at risk for the development of hemolytic anemia when given 8-aminoquinolines (8-AQs), an important class of antimalarial/antiinfective therapeutics. However, there is no suitable animal model that can predict the clinical hemolytic potential of drugs. We developed and validated a human (hu)RBC-SCID mouse model by giving nonobese diabetic/SCID mice daily transfusions of huRBCs from G6PD-deficient donors. Treatment of SCID mice engrafted with G6PD-deficient huRBCs with primaquine, an 8-AQ, resulted in a dose-dependent selective loss of huRBCs. To validate the specificity of this model, we tested known nonhemolytic antimalarial drugs: mefloquine, chloroquine, doxycycline, and pyrimethamine. No significant loss of G6PD-deficient huRBCs was observed. Treatment with drugs known to cause hemolytic toxicity (pamaquine, sitamaquine, tafenoquine, and dapsone) resulted in loss of G6PD-deficient huRBCs comparable to primaquine. This mouse model provides an important tool to test drugs for their potential to cause hemolytic toxicity in G6PD-deficient populations.

  17. Humanized mouse model of glucose 6-phosphate dehydrogenase deficiency for in vivo assessment of hemolytic toxicity

    PubMed Central

    Rochford, Rosemary; Ohrt, Colin; Baresel, Paul C.; Campo, Brice; Sampath, Aruna; Magill, Alan J.; Tekwani, Babu L.; Walker, Larry A.

    2013-01-01

    Individuals with glucose 6-phosphate dehydrogenase (G6PD) deficiency are at risk for the development of hemolytic anemia when given 8-aminoquinolines (8-AQs), an important class of antimalarial/antiinfective therapeutics. However, there is no suitable animal model that can predict the clinical hemolytic potential of drugs. We developed and validated a human (hu)RBC-SCID mouse model by giving nonobese diabetic/SCID mice daily transfusions of huRBCs from G6PD-deficient donors. Treatment of SCID mice engrafted with G6PD-deficient huRBCs with primaquine, an 8-AQ, resulted in a dose-dependent selective loss of huRBCs. To validate the specificity of this model, we tested known nonhemolytic antimalarial drugs: mefloquine, chloroquine, doxycycline, and pyrimethamine. No significant loss of G6PD-deficient huRBCs was observed. Treatment with drugs known to cause hemolytic toxicity (pamaquine, sitamaquine, tafenoquine, and dapsone) resulted in loss of G6PD-deficient huRBCs comparable to primaquine. This mouse model provides an important tool to test drugs for their potential to cause hemolytic toxicity in G6PD-deficient populations. PMID:24101478

  18. Expression and characterization of a cytosolic glucose 6 phosphate dehydrogenase isoform from barley (Hordeum vulgare) roots.

    PubMed

    Castiglia, Daniela; Cardi, Manuela; Landi, Simone; Cafasso, Donata; Esposito, Sergio

    2015-08-01

    In plant cells, glucose 6 phosphate dehydrogenase (G6PDH-EC 1.1.1.49) regulates the oxidative pentose phosphate pathway (OPPP), a metabolic route involved in the production of NADPH for various biosynthetic processes and stress response. In this study, we report the overexpression of a cytosolic G6PDH isoform from barley (Hordeum vulgare) roots in bacteria, and the biochemical characterization of the purified recombinant enzyme (HvCy-G6PDH). A full-length cDNA coding for a cytosolic isoform of G6PDH was isolated, and the sequence was cloned into pET3d vector; the protein was overexpressed in Escherichia coli BL21 (DE3) and purified by anion exchange and affinity chromatography. The kinetic properties were calculated: the recombinant HvCy-G6PDH showed KMs and KINADPH comparable to those observed for the enzyme purified from barley roots; moreover, the analysis of NADPH inhibition suggested a competitive mechanism. Therefore, this enzyme could be utilised for the structural and regulatory characterization of this isoform in higher plants.

  19. Design of an interface peptide as new inhibitor of human glucose-6-phosphate dehydrogenase.

    PubMed

    Obiol-Pardo, Cristian; Alcarraz-Vizán, Gema; Díaz-Moralli, Santiago; Cascante, Marta; Rubio-Martinez, Jaime

    2014-04-01

    Glucose-6-phosphate dehydrogenase (G6PDH) is an essential enzyme involved in the first reaction of the oxidative branch of the pentose phosphate pathway (PPP). Recently, G6PDH was suggested as a novel target protein for cancer therapy as one of the final products of the PPP, ribose-5-phosphate, is necessary for nucleic acid synthesis and tumor progression. After analyzing the protein-protein interface of the crystal structure of human G6PDH by means of molecular dynamics simulations, we designed six interface peptides based on the natural sequence of the protein. The three most promising peptides, as predicted by binding free energy calculations, were synthesized and one of them was confirmed as a novel inhibitor of human G6PDH in experimental assays. Together, the active peptide found and its suggested binding mode proposes a new strategy for inhibiting this enzyme and should aid the further design of novel, potent and non-peptidic G6PDH inhibitors. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Glucose-6-Phosphate Isomerase (G6PI) Mediates Hypoxia-Induced Angiogenesis in Rheumatoid Arthritis

    PubMed Central

    Lu, Ying; Yu, Shan-Shan; Zong, Ming; Fan, Sha-Sha; Lu, Tian-Bao; Gong, Ru-Han; Sun, Li-Shan; Fan, Lie-Ying

    2017-01-01

    The higher level of Glucose-6-phosphate isomerase (G6PI) has been found in both synovial tissue and synovial fluid of rheumatoid arthritis (RA) patients, while the function of G6PI in RA remains unclear. Herein we found the enrichment of G6PI in microvascular endothelial cells of synovial tissue in RA patients, where a 3% O2 hypoxia environment has been identified. In order to determine the correlation between the high G6PI level and the low oxygen concentration in RA, a hypoxia condition (~3% O2) in vitro was applied to mimic the RA environment in vivo. Hypoxia promoted cellular proliferation of rheumatoid arthritis synovial fibroblasts (RASFs), and induced cell migration and angiogenic tube formation of human dermal microvascular endothelial cells (HDMECs), which were accompanied with the increased expression of G6PI and HIF-1α. Through application of G6PI loss-of-function assays, we confirmed the requirement of G6PI expression for those hypoxia-induced phenotype in RA. In addition, we demonstrated for the first time that G6PI plays key roles in regulating VEGF secretion from RASFs to regulate the hypoxia-induced angiogenesis in RA. Taken together, we demonstrated a novel pathway regulating hypoxia-induced angiogenesis in RA mediated by G6PI. PMID:28067317

  1. Resistance of glucose-6-phosphate dehydrogenase deficiency to malaria: effects of fava bean hydroxypyrimidine glucosides on Plasmodium falciparum growth in culture and on the phagocytosis of infected cells.

    PubMed

    Ginsburg, H; Atamna, H; Shalmiev, G; Kanaani, J; Krugliak, M

    1996-07-01

    The balanced polymorphism of glucose-6-phosphate dehydrogenase deficiency (G6PD-) is believed to have evolved through the selective pressure of malarial combined with consumption of fava beans. The implicated fava bean constituents are the hydroxypyrimidine glucosides vicine and convicine, which upon hydrolysis of their beta-O-glucosidic bond, became protein pro-oxidants. In this work we show that the glucosides inhibit the growth of Plasmodium falciparum, increase the hexose-monophosphate shunt activity and the phagocytosis of malaria-infected erythrocytes. These activities are exacerbated in the presence of beta-glucosidase, implicating their pro-oxidant aglycones in the toxic effect, and are more pronounced in infected G6PD- erythrocytes. These results suggest that G6PD- infected erythrocytes are more susceptible to phagocytic cells, and that fava bean pro-oxidants are more efficiently suppressing parasite propagation in G6PD- erythrocytes, either by directly affecting parasite growth, or by means of enhanced phagocytic elimination of infected cells. The present findings could account for the relative resistance of G6PD- bearers to falciparum malaria, and establish a link between dietary habits and malaria in the selection of the G6PD- genotype.

  2. Type I glycogen storage diseases: disorders of the glucose-6-phosphatase/glucose-6-phosphate transporter complexes.

    PubMed

    Chou, Janice Y; Jun, Hyun Sik; Mansfield, Brian C

    2015-05-01

    Disorders of the glucose-6-phosphatase (G6Pase)/glucose-6-phosphate transporter (G6PT) complexes consist of three subtypes: glycogen storage disease type Ia (GSD-Ia), deficient in the liver/kidney/intestine-restricted G6Pase-α (or G6PC); GSD-Ib, deficient in a ubiquitously expressed G6PT (or SLC37A4); and G6Pase-β deficiency or severe congenital neutropenia syndrome type 4 (SCN4), deficient in the ubiquitously expressed G6Pase-β (or G6PC3). G6Pase-α and G6Pase-β are glucose-6-phosphate (G6P) hydrolases with active sites lying inside the endoplasmic reticulum (ER) lumen and as such are dependent upon the G6PT to translocate G6P from the cytoplasm into the lumen. The tissue expression profiles of the G6Pase enzymes dictate the disease's phenotype. A functional G6Pase-α/G6PT complex maintains interprandial glucose homeostasis, while a functional G6Pase-β/G6PT complex maintains neutrophil/macrophage energy homeostasis and functionality. G6Pase-β deficiency is not a glycogen storage disease but biochemically it is a GSD-I related syndrome (GSD-Irs). GSD-Ia and GSD-Ib patients manifest a common metabolic phenotype of impaired blood glucose homeostasis not shared by GSD-Irs. GSD-Ib and GSD-Irs patients manifest a common myeloid phenotype of neutropenia and neutrophil/macrophage dysfunction not shared by GSD-Ia. While a disruption of the activity of the G6Pase-α/G6PT complex readily explains why GSD-Ia and GSD-Ib patients exhibit impaired glucose homeostasis, the basis for neutropenia and myeloid dysfunction in GSD-Ib and GSD-Irs are only now starting to be understood. Animal models of all three disorders are now available and are being exploited to both delineate the disease more precisely and develop new treatment approaches, including gene therapy.

  3. Glucose regulates enzymatic sources of mitochondrial NADPH in skeletal muscle cells; a novel role for glucose-6-phosphate dehydrogenase.

    PubMed

    Mailloux, Ryan J; Harper, Mary-Ellen

    2010-07-01

    Reduced nicotinamide adenine dinucleotide (NADPH) is a functionally important metabolite required to support numerous cellular processes. However, despite the identification of numerous NADPH-producing enzymes, the mechanisms underlying how the organellar pools of NADPH are maintained remain elusive. Here, we have identified glucose-6-phosphate dehydrogenase (G6PDH) as an important source of NADPH in mitochondria. Activity analysis, submitochondrial fractionation, fluorescence microscopy, and protease sensitivity assays revealed that G6PDH is localized to the mitochondrial matrix. 6-ANAM, a specific G6PDH inhibitor, depleted mitochondrial NADPH pools and increased oxidative stress revealing the importance of G6PDH in NADPH maintenance. We also show that glucose availability and differences in metabolic state modulate the enzymatic sources of NADPH in mitochondria. Indeed, cells cultured in high glucose (HG) not only adopted a glycolytic phenotype but also relied heavily on matrix-associated G6PDH as a source of NADPH. In contrast, cells exposed to low-glucose (LG) concentrations, which displayed increased oxygen consumption, mitochondrial metabolic efficiency, and decreased glycolysis, relied predominantly on isocitrate dehydrogenase (ICDH) as the principal NADPH-producing enzyme in the mitochondria. Culturing glycolytic cells in LG for 48 h decreased G6PDH and increased ICDH protein levels in the mitochondria, further pointing to the regulatory role of glucose. 2-Deoxyglucose treatment also prevented the increase of mitochondrial G6PDH in response to HG. The role of glucose in regulating enzymatic sources of mitochondrial NADPH pool maintenance was confirmed using human myotubes from obese adults with a history of type 2 diabetes mellitus (post-T2DM). Myotubes from post-T2DM participants failed to increase mitochondrial G6PDH in response to HG in contrast to mitochondria in myotubes from control participants (non-T2DM). Hence, we not only identified a matrix

  4. Glucose-induced glycogenesis in the liver involves the glucose-6-phosphate-dependent dephosphorylation of glycogen synthase.

    PubMed Central

    Cadefau, J; Bollen, M; Stalmans, W

    1997-01-01

    Non-metabolized glucose derivatives may cause inactivation of phosphorylase but, unlike glucose, they are unable to elicit activation of glycogen synthase in isolated hepatocytes. We report here that, after the previous inactivation of phosphorylase by one of these glucose derivatives (2-deoxy-2-fluoro-alpha-glucosyl fluoride), glycogen synthase was progressively activated by addition of increasing concentrations of glucose. Under these conditions, the degree of activation of glycogen synthase was linearly correlated with the intracellular glucose-6-phosphate (Glc-6-P) concentration. Addition of glucosamine, an inhibitor of glucokinase, decreased both parameters in parallel. Further experiments using an inhibitor of either protein kinases (5-iodotubercidin) or protein phosphatases (microcystin) in isolated hepatocytes indicated that Glc-6-P does not affect glycogen-synthase kinase activity but enhances the glycogen-synthase phosphatase reaction. Experiments in vitro showed that the synthase phosphatase activity of glycogen-bound type-1 protein phosphatase was increased by physiological concentrations of Glc-6-P (0.1-0.5 mM), but not by 2.5 mM fructose-6-P, fructose-1-P or glucose-1-P. At physiological ionic strength, the glycogen-associated synthase phosphatase activity was nearly entirely Glc-6-P-dependent, but Glc-6-P did not relieve the strong inhibitory effect of phosphorylase a. The large stimulatory effects of 2.5 mM Glc-6-P, with glycogen synthase b and phosphorylase a as substrates, appeared to be mostly substrate-directed, while the modest effects observed with casein and histone IIA pointed to an additional stimulation of glycogen-bound protein phosphatase-1 by Glc-6-P. We conclude that glucose elicits hepatic synthase phosphatase activity both by removal of the inhibitor, phosphorylase a, and by generation of the stimulator, Glc-6-P. PMID:9148744

  5. Glucose-induced glycogenesis in the liver involves the glucose-6-phosphate-dependent dephosphorylation of glycogen synthase.

    PubMed

    Cadefau, J; Bollen, M; Stalmans, W

    1997-03-15

    Non-metabolized glucose derivatives may cause inactivation of phosphorylase but, unlike glucose, they are unable to elicit activation of glycogen synthase in isolated hepatocytes. We report here that, after the previous inactivation of phosphorylase by one of these glucose derivatives (2-deoxy-2-fluoro-alpha-glucosyl fluoride), glycogen synthase was progressively activated by addition of increasing concentrations of glucose. Under these conditions, the degree of activation of glycogen synthase was linearly correlated with the intracellular glucose-6-phosphate (Glc-6-P) concentration. Addition of glucosamine, an inhibitor of glucokinase, decreased both parameters in parallel. Further experiments using an inhibitor of either protein kinases (5-iodotubercidin) or protein phosphatases (microcystin) in isolated hepatocytes indicated that Glc-6-P does not affect glycogen-synthase kinase activity but enhances the glycogen-synthase phosphatase reaction. Experiments in vitro showed that the synthase phosphatase activity of glycogen-bound type-1 protein phosphatase was increased by physiological concentrations of Glc-6-P (0.1-0.5 mM), but not by 2.5 mM fructose-6-P, fructose-1-P or glucose-1-P. At physiological ionic strength, the glycogen-associated synthase phosphatase activity was nearly entirely Glc-6-P-dependent, but Glc-6-P did not relieve the strong inhibitory effect of phosphorylase a. The large stimulatory effects of 2.5 mM Glc-6-P, with glycogen synthase b and phosphorylase a as substrates, appeared to be mostly substrate-directed, while the modest effects observed with casein and histone IIA pointed to an additional stimulation of glycogen-bound protein phosphatase-1 by Glc-6-P. We conclude that glucose elicits hepatic synthase phosphatase activity both by removal of the inhibitor, phosphorylase a, and by generation of the stimulator, Glc-6-P.

  6. High frequency of diabetes and impaired fasting glucose in patients with glucose-6-phosphate dehydrogenase deficiency in the Western brazilian Amazon.

    PubMed

    Santana, Marli S; Monteiro, Wuelton M; Costa, Mônica R F; Sampaio, Vanderson S; Brito, Marcelo A M; Lacerda, Marcus V G; Alecrim, Maria G C

    2014-07-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common human genetic abnormalities, and it has a significant prevalence in the male population (X chromosome linked). The purpose of this study was to estimate the frequency of impaired fasting glucose and diabetes among G6PD-deficient persons in Manaus, Brazil, an area in the Western Brazilian Amazon to which malaria is endemic. Glucose-6-phosphate dehydrogenase-deficient males had more impaired fasting glucose and diabetes. This feature could be used as a screening tool for G6PD-deficient persons who are unable to use primaquine for the radical cure of Plasmodium vivax malaria.

  7. The preparation of nylon-tube-supported hexokinase and glucose 6-phosphate dehydrogenase and the use of the co-immobilized enzymes in the automated determination of glucose.

    PubMed Central

    Morris, D L; Campbell, J; Hornby, W E

    1975-01-01

    Triethyloxonium tetrafluoroborate was used to O-alkylate nylon-tube thus producing the imidate salt of the nylon which was further made to react with 1,6-diaminohexane. 2. Hexokinase (EC 2.7.1.1) and glucose 6-phosphate dehydrogenase (EC 1.1.1.49) were immobilized on the amino-substituted nylon tube through glutaraldeyde and bisimidates. 3. The effect of varying the conditions of O-alkylation and the amount of enzyme immobilized on the activity of nylon tube-hexokinase derivatives was determined. 4. The effect of varying the amount of enzyme immobilized on the activity of nylon-tube-glucose 6-phosphate dehydrogenase derivatives was determined. 5. The thermal stability of nylon-tube-hexokinase and nylon-tube-glucose 6-phosphate dehydrogenase derivatives was studied. 6. Different ratios of hexokinase and glucose 6-phosphate dehydrogenase were co-immobilized on nylon tube, and the rate of conversion of glucose into 6-phosphogluconolactone was compared with the individual activities of the immobilized enzymes. 7. Hexokinase and glucose 6-phosphate dehydrogenase co-immobilized on nylon tube were used in the automated analysis of glucose. PMID:1167161

  8. Producing glucose 6-phosphate from cellulosic biomass: Structural insights into levoglucosan bioconversion

    SciTech Connect

    Bacik, John -Paul; Klesmith, Justin R.; Whitehead, Timothy A.; Jarboe, Laura R.; Unkefer, Clifford J.; Mark, Brian L.; Michalczyk, Ryszard

    2015-09-09

    The most abundant carbohydrate product of cellulosic biomass pyrolysis is the anhydrosugar levoglucosan (1,6-anhydro-β-d-glucopyranose), which can be converted to glucose 6-phosphate by levoglucosan kinase (LGK). In addition to the canonical kinase phosphotransfer reaction, the conversion requires cleavage of the 1,6-anhydro ring to allow ATP-dependent phosphorylation of the sugar O6 atom. Using x-ray crystallography, we show that LGK binds two magnesium ions in the active site that are additionally coordinated with the nucleotide and water molecules to result in ideal octahedral coordination. To further verify the metal binding sites, we co-crystallized LGK in the presence of manganese instead of magnesium and solved the structure de novo using the anomalous signal from four manganese atoms in the dimeric structure. The first metal is required for catalysis, whereas our work suggests that the second is either required or significantly promotes the catalytic rate. Although the enzyme binds its sugar substrate in a similar orientation to the structurally related 1,6-anhydro-N-acetylmuramic acid kinase (AnmK), it forms markedly fewer bonding interactions with the substrate. In this orientation, the sugar is in an optimal position to couple phosphorylation with ring cleavage. We also observed a second alternate binding orientation for levoglucosan, and in these structures, ADP was found to bind with lower affinity. These combined observations provide an explanation for the high Km of LGK for levoglucosan. Furthermore, greater knowledge of the factors that contribute to the catalytic efficiency of LGK can be used to improve applications of this enzyme for levoglucosan-derived biofuel production.

  9. Data mining and pathway analysis of glucose-6-phosphate dehydrogenase with natural language processing.

    PubMed

    Chen, Long; Zhang, Chunhua; Wang, Yanling; Li, Yuqian; Han, Qiaoqiao; Yang, Huixin; Zhu, Yuechun

    2017-08-01

    Human glucose-6-phosphate dehydrogenase (G6PD) is a crucial enzyme in the pentose phosphate pathway, and serves an important role in biosynthesis and the redox balance. G6PD deficiency is a major cause of neonatal jaundice and acute hemolyticanemia, and recently, G6PD has been associated with diseases including inflammation and cancer. The aim of the present study was to conduct a search of the National Center for Biotechnology Information PubMed library for articles discussing G6PD. Genes that were identified to be associated with G6PD were recorded, and the frequency at which each gene appeared was calculated. Gene ontology (GO), pathway and network analyses were then performed. A total of 98 G6PD‑associated genes and 33 microRNAs (miRNAs) that potentially regulate G6PD were identified. The 98 G6PD‑associated genes were then sub‑classified into three functional groups by GO analysis, followed by analysis of function, pathway, network, and disease association. Out of the 47 signaling pathways identified, seven were significantly correlated with G6PD‑associated genes. At least two out of four independent programs identified the 33 miRNAs that were predicted to target G6PD. miR‑1207‑5P, miR‑1 and miR‑125a‑5p were predicted by all four software programs to target G6PD. The results of the present study revealed that dysregulation of G6PD was associated with cancer, autoimmune diseases, and oxidative stress‑induced disorders. These results revealed the potential roles of G6PD‑regulated signaling and metabolic pathways in the etiology of these diseases.

  10. Importance of glucose-6-phosphate dehydrogenase (G6PDH) for vanillin tolerance in Saccharomyces cerevisiae.

    PubMed

    Nguyen, Trinh Thi My; Kitajima, Sakihito; Izawa, Shingo

    2014-09-01

    Vanillin is derived from lignocellulosic biomass and, as one of the major biomass conversion inhibitors, inhibits yeast growth and fermentation. Vanillin was recently shown to induce the mitochondrial fragmentation and formation of mRNP granules such as processing bodies and stress granules in Saccharomyces cerevisiae. Furfural, another major biomass conversion inhibitor, also induces oxidative stress and is reduced in an NAD(P)H-dependent manner to its less toxic alcohol derivative. Therefore, the pentose phosphate pathway (PPP), through which most NADPH is generated, plays a role in tolerance to furfural. Although vanillin also induces oxidative stress and is reduced to vanillyl alcohol in a NADPH-dependent manner, the relationship between vanillin and PPP has not yet been investigated. In the present study, we examined the importance of glucose-6-phosphate dehydrogenase (G6PDH), which catalyzes the rate-limiting NADPH-producing step in PPP, for yeast tolerance to vanillin. The growth of the null mutant of G6PDH gene (zwf1Δ) was delayed in the presence of vanillin, and vanillin was efficiently reduced in the culture of wild-type cells but not in the culture of zwf1Δ cells. Furthermore, zwf1Δ cells easily induced the activation of Yap1, an oxidative stress responsive transcription factor, mitochondrial fragmentation, and P-body formation with the vanillin treatment, which indicated that zwf1Δ cells were more susceptible to vanillin than wild type cells. These findings suggest the importance of G6PDH and PPP in the response of yeast to vanillin.

  11. Molecular study of ovine glucose 6-phosphate dehydrogenase gene expression in respect to different energy intake.

    PubMed

    Laliotis, George P; Vitsa, Alkistis; Bizelis, Iosif; Charismiadou, Maria A; Rogdakis, Emmanuel

    2010-06-01

    Glucose 6-phosphate dehydrogenase (G6PD) plays an important role in a ruminant's metabolism catalyzing the first committed reaction in the pentose phosphate pathway as it provides necessary compounds of NADPH for the synthesis of fatty acids. The cloning of ovine (Ovis aries) G6PD gene revealed the presence of two cDNA transcripts (oG6PD(A) and oG6PD(B)), with oG6PD(B) being a product of alternative splicing and with no similarity to any other previously reported G6PD transcript. Here, we attempt to study the effect of energy balance in ovine G6PD transcript expression, trying simultaneously to find out any potential physiological role of the oG6PD(B) transcript. Changes of energy balance that lead to synergistic changes in the expression of both transcripts, but in opposite directions and not in a proportional way. Negative energy balance favours the presence of the oG6PD(B) transcript leading to a significant increase of its expression, compared to oG6PD(A) expression (P<0.05). In contrast, positive energy balance leads to a significant increase of oG6PD(A) compared to oG6PD(B) expression (P<0.05). In either condition oG6PD(B) expression is unchanged. Regression analysis showed that there is an energy balance threshold where the expression of both transcripts shows no change. 2010 Elsevier Inc. All rights reserved.

  12. Genetic Profiles of Korean Patients With Glucose-6-Phosphate Dehydrogenase Deficiency

    PubMed Central

    Lee, Jaewoong; Choi, Hayoung; Kim, Jiyeon; Kwon, Ahlm; Jang, Woori; Chae, Hyojin; Kim, Myungshin; Kim, Yonggoo; Lee, Jae Wook; Chung, Nack-Gyun

    2017-01-01

    Background We describe the genetic profiles of Korean patients with glucose-6-phosphate dehydrogenase (G6PD) deficiencies and the effects of G6PD mutations on protein stability and enzyme activity on the basis of in silico analysis. Methods In parallel with a genetic analysis, the pathogenicity of G6PD mutations detected in Korean patients was predicted in silico. The simulated effects of G6PD mutations were compared to the WHO classes based on G6PD enzyme activity. Four previously reported mutations and three newly diagnosed patients with missense mutations were estimated. Results One novel mutation (p.Cys385Gly, labeled G6PD Kangnam) and two known mutations [p.Ile220Met (G6PD São Paulo) and p.Glu416Lys (G6PD Tokyo)] were identified in this study. G6PD mutations identified in Koreans were also found in Brazil (G6PD São Paulo), Poland (G6PD Seoul), United States of America (G6PD Riley), Mexico (G6PD Guadalajara), and Japan (G6PD Tokyo). Several mutations occurred at the same nucleotide, but resulted in different amino acid residue changes in different ethnic populations (p.Ile380 variant, G6PD Calvo Mackenna; p.Cys385 variants, Tomah, Madrid, Lynwood; p.Arg387 variant, Beverly Hills; p.Pro396 variant, Bari; and p.Pro396Ala in India). On the basis of the in silico analysis, Class I or II mutations were predicted to be highly deleterious, and the effects of one Class IV mutation were equivocal. Conclusions The genetic profiles of Korean individuals with G6PD mutations indicated that the same mutations may have arisen by independent mutational events, and were not derived from shared ancestral mutations. The in silico analysis provided insight into the role of G6PD mutations in enzyme function and stability. PMID:28028996

  13. Association of glucose-6-phosphate dehydrogenase deficiency and malaria: a systematic review and meta-analysis

    PubMed Central

    Mbanefo, Evaristus Chibunna; Ahmed, Ali Mahmoud; Titouna, Afaf; Elmaraezy, Ahmed; Trang, Nguyen Thi Huyen; Phuoc Long, Nguyen; Hoang Anh, Nguyen; Diem Nghi, Tran; The Hung, Bui; Van Hieu, Mai; Ky Anh, Nguyen; Huy, Nguyen Tien; Hirayama, Kenji

    2017-01-01

    Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency overlaps with malaria endemicity although it predisposes carriers to hemolysis. This fact supports the protection hypothesis against malaria. The aim of this systematic review is to assess the presence and the extent of protective association between G6PD deficiency and malaria. Thirteen databases were searched for papers reporting any G6PD alteration in malaria patients. Twenty-eight of the included 30 studies were eligible for the meta-analysis. Results showed absence of negative association between G6PD deficiency and uncomplicated falciparum malaria (odds ratio (OR), 0.77; 95% confidence interval (CI), 0.59–1.02; p = 0.07). However, this negative association happened in Africa (OR, 0.59; 95% CI, 0.40–0.86; p = 0.007) but not in Asia (OR, 1.24; 95% CI, 0.96–1.61; p = 0.10), and in the heterozygotes (OR, 0.70; 95% CI, 0.57–0.87; p = 0.001) but not the homo/hemizygous (OR, 0.70; 95% CI, 0.46–1.07; p = 0.10). There was no association between G6PD deficiency and total severe malaria (OR, 0.82; 95% CI, 0.61–1.11; p = 0.20). Similarly, there was no association with other malaria species. G6PD deficiency can potentially protect against uncomplicated malaria in African countries, but not severe malaria. Interestingly, this protection was mainly in heterozygous, being x-linked thus related to gender. PMID:28382932

  14. A new paper-based analytical device for detection of Glucose-6-phosphate dehydrogenase deficiency.

    PubMed

    Kaewarsa, Phuritat; Laiwattanapaisal, Wanida; Palasuwan, Attakorn; Palasuwan, Duangdao

    2017-03-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a genetic haemolytic disorder. Most persons with G6PD deficiency are asymptomatic, but exposure to oxidant drugs, such as the anti-malarial drug primaquine, may induce haemolysis, which is commonly found in Asian countries. A reliable test is necessary for diagnosing the deficiency to prevent an acute haemolytic crisis. This study proposes a novel quantitative method to detect G6PD deficiency using paper-based analytical devices (G6PDD-PAD). Wax printing was utilized for fabricating circular reaction zone patterns in paper. The colorimetric assay is based on the formation of formazan via a reduction of tetra-nitro blue tetrazolium (TNBT) by the G6PD enzyme on G6PDD-PAD. Detection was achieved by capturing the colour using a desktop scanner and the colour intensity was analysed with Adobe Photoshop C56. The results showed that the G6PD activity analysed by G6PDD-PAD was highly correlated with the standard biochemical assay (SBA) (r(2)=0.87, p<0.01). Moreover, good agreement by Bland-Altman bias plot was demonstrated between G6PDD-PAD and the SBA (mean bias 1.4 IU/gHb). The detection limit was 0 IU/gHb of G6PD activity. This study demonstrates the feasibility of using G6PDD-PAD. This simple, low-cost test ($0.1/test) should be useful for diagnosing G6PD deficiency in resource-limited settings. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Diversity in expression of glucose-6-phosphate dehydrogenase deficiency in females.

    PubMed

    Abdulrazzaq, Y M; Micallef, R; Qureshi, M; Dawodu, A; Ahmed, I; Khidr, A; Bastaki, S M; Al-Khayat, A; Bayoumi, R A

    1999-01-01

    The aims of this study were to determine the prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency in the United Arab Emirates (UAE), to describe the different mutations in the population, to determine its prevalence, and to study inheritance patterns in families of G6PD-deficient individuals. All infants born at Tawam Hospital, Al-Ain, UAE from January 1994 to September 1996 were screened at birth for their G6PD status. In addition, those attending well-baby clinics during the period were also screened for the disorder. Families of 40 known G6PD-deficient individuals, selected randomly from the records of three hospitals in the country, were assessed for G6PD deficiency. Where appropriate, this was followed by definition of G6PD mutations. Of 8198 infants, 746 (9.1%), comprising 15% of males and 5% of females tested, were found to be G6PD deficient. A total of 27 families were further assessed: of these, all but one family had the nt563 Mediterranean mutation. In one family, two individuals had the nt202 African mutation. The high manifestation of G6PD deficiency in women may be due to the preferential expression of the G6PD-deficient gene and X-inactivation of the normal gene, and/or to the presence of an 'enhancer' gene that makes the expression of the G6PD deficiency more likely. The high level of consanguinity which, theoretically, should result in a high proportion of homozygotes and consequently a higher proportion of females with the deficiency, was not found to be a significant factor.

  16. Glucose-6-Phosphate Dehydrogenase Deficiency and Physical and Mental Health until Adolescence

    PubMed Central

    Kwok, Man Ki; Leung, Gabriel M.; Schooling, C. Mary

    2016-01-01

    Background To examine the association of glucose-6-phosphate dehydrogenase (G6PD) deficiency with adolescent physical and mental health, as effects of G6PD deficiency on health are rarely reported. Methods In a population-representative Chinese birth cohort: “Children of 1997” (n = 8,327), we estimated the adjusted associations of G6PD deficiency with growth using generalized estimating equations, with pubertal onset using interval censored regression, with hospitalization using Cox proportional hazards regression and with size, blood pressure, pubertal maturation and mental health using linear regression with multiple imputation and inverse probability weighting. Results Among 5,520 screened adolescents (66% follow-up), 4.8% boys and 0.5% girls had G6PD deficiency. G6PD-deficiency was not associated with birth weight-for-gestational age or length/height gain into adolescence, but was associated with lower childhood body mass index (BMI) gain (-0.38 z-score, 95% confidence interval (CI) -0.57, -0.20), adjusted for sex and parental education, and later onset of pubic hair development (time ratio = 1.029, 95% CI 1.007, 1.050). G6PD deficiency was not associated with blood pressure, height, BMI or mental health in adolescence, nor with serious infectious morbidity until adolescence. Conclusions G6PD deficient adolescents had broadly similar physical and mental health indicators, but transiently lower BMI gain and later pubic hair development, whose long-term implications warrant investigation. PMID:27824927

  17. Impact of glucose-6-phosphate dehydrogenase deficiency on the pathophysiology of cardiovascular disease

    PubMed Central

    Hecker, Peter A.; Leopold, Jane A.; Gupte, Sachin A.; Recchia, Fabio A.

    2013-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) catalyzes the rate-determining step in the pentose phosphate pathway and produces NADPH to fuel glutathione recycling. G6PD deficiency is the most common enzyme deficiency in humans and affects over 400 million people worldwide; however, its impact on cardiovascular disease is poorly understood. The glutathione pathway is paramount to antioxidant defense, and G6PD-deficient cells do not cope well with oxidative damage. Limited clinical evidence indicates that G6PD deficiency may be associated with hypertension. However, there are also data to support a protective role of G6PD deficiency in decreasing the risk of heart disease and cardiovascular-associated deaths, perhaps through a decrease in cholesterol synthesis. Studies in G6PD-deficient (G6PDX) mice are mixed and provide evidence for both protective and deleterious effects. G6PD deficiency may provide a protective effect through decreasing cholesterol synthesis, superoxide production, and reductive stress. However, recent studies indicate that G6PDX mice are moderately more susceptible to ventricular dilation in response to myocardial infarction or pressure overload-induced heart failure. Furthermore, G6PDX hearts do not recover as well as nondeficient mice when faced with ischemia-reperfusion injury, and G6PDX mice are susceptible to the development of age-associated cardiac hypertrophy. Overall, the limited available data indicate a complex interplay in which adverse effects of G6PD deficiency may outweigh potential protective effects in the face of cardiac stress. Definitive clinical studies in large populations are needed to determine the effects of G6PD deficiency on the development of cardiovascular disease and subsequent outcomes. PMID:23241320

  18. Association of glucose-6-phosphate dehydrogenase deficiency and malaria: a systematic review and meta-analysis.

    PubMed

    Mbanefo, Evaristus Chibunna; Ahmed, Ali Mahmoud; Titouna, Afaf; Elmaraezy, Ahmed; Trang, Nguyen Thi Huyen; Phuoc Long, Nguyen; Hoang Anh, Nguyen; Diem Nghi, Tran; The Hung, Bui; Van Hieu, Mai; Ky Anh, Nguyen; Huy, Nguyen Tien; Hirayama, Kenji

    2017-04-06

    Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency overlaps with malaria endemicity although it predisposes carriers to hemolysis. This fact supports the protection hypothesis against malaria. The aim of this systematic review is to assess the presence and the extent of protective association between G6PD deficiency and malaria. Thirteen databases were searched for papers reporting any G6PD alteration in malaria patients. Twenty-eight of the included 30 studies were eligible for the meta-analysis. Results showed absence of negative association between G6PD deficiency and uncomplicated falciparum malaria (odds ratio (OR), 0.77; 95% confidence interval (CI), 0.59-1.02; p = 0.07). However, this negative association happened in Africa (OR, 0.59; 95% CI, 0.40-0.86; p = 0.007) but not in Asia (OR, 1.24; 95% CI, 0.96-1.61; p = 0.10), and in the heterozygotes (OR, 0.70; 95% CI, 0.57-0.87; p = 0.001) but not the homo/hemizygous (OR, 0.70; 95% CI, 0.46-1.07; p = 0.10). There was no association between G6PD deficiency and total severe malaria (OR, 0.82; 95% CI, 0.61-1.11; p = 0.20). Similarly, there was no association with other malaria species. G6PD deficiency can potentially protect against uncomplicated malaria in African countries, but not severe malaria. Interestingly, this protection was mainly in heterozygous, being x-linked thus related to gender.

  19. Screening and prevention of neonatal glucose 6-phosphate dehydrogenase deficiency in Guangzhou, China.

    PubMed

    Jiang, J; Li, B; Cao, W; Jiang, X; Jia, X; Chen, Q; Wu, J

    2014-06-09

    We aimed to summarize the results of screening protocol and prevention of neonatal glucose 6-phosphate dehydrogenase (G6PD) deficiency during a 22-year-long period to provide a basis of reference for the screening of this disease. About 1,705,569 newborn subjects in Guangzhou City were screened for this deficiency. Specimens were collected according to the conventional method of specimen acquisition for "newborn dried bloodspot screening", preserved, and inspected. The specimens were studied with fluorescent spot test and quantitative fluorescence assay. Diagnosis was performed using the modified NBTG6PD/6PGD ratio method. Bloodspot filter paper specimens were sent to the laboratory within 24 h via EMS Express, and the G6PD test was performed on the same day. The G6PD deficiency-positive rate was 4.2% in the samples screened using the fluorescent spot test, while it was 5% in case of the quantitative fluorescence assay. Neonatal screening for G6PD deficiency for 11,437 cases (6117 boys and 5320 girls) showed positive results in 481 cases. About 420 cases (318 boys and 102 girls) of G6PD deficiency were confirmed with the modified Duchenne NBT ratio method. The total detection rate was 3.7:5.2% for boys and 1.9% for girls. Quantitative fluorescence assay improved the sensitivity and detection rate. Accelerating the speed of sample delivery by using Internet network systems and ensuring online availability of screening results can aid the screening and diagnosis of this deficiency within 1 week of birth.

  20. Glucose-6-phosphate dehydrogenase deficiency in Tunisia: molecular data and phenotype-genotype association.

    PubMed

    Laouini, N; Bibi, A; Ammar, H; Kazdaghli, K; Ouali, F; Othmani, R; Amdouni, S; Haloui, S; Sahli, C A; Jouini, L; Hadj Fredj, S; Siala, H; Ben Romdhane, N; Toumi, N E; Fattoum, S; Messsaoud, T

    2013-02-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme defect. In this study, we aimed to perform a molecular investigation of G6PD deficiency in Tunisia and to associate clinical manifestations and the degree of deficiency with the genotype. A total of 161 Tunisian subjects of both sexes were screened by spectrophotometric assay for enzyme activity. Out of these, 54 unrelated subjects were selected for screening of the most frequent mutations in Tunisia by PCR/RFLP, followed by size-based separation of double-stranded fragments under non-denaturing conditions on a denaturing high performance liquid chromatography system. Of the 56 altered chromosomes examined, 75 % had the GdA(-) mutation, 14.28 % showed the GdB(-) mutation and no mutations were identified in 10.72 % of cases. Hemizygous males with GdA(-) mutation were mostly of class III, while those with GdB(-) mutation were mainly of class II. The principal clinical manifestation encountered was favism. Acute hemolytic crises induced by drugs or infections and neonatal jaundice were also noted. Less severe clinical features such as low back pain were present in heterozygous females and in one homozygous female. Asymptomatic individuals were in majority heterozygote females and strangely one hemizygous male. The spectrum of mutations seems to be homogeneous and similar to that of Mediterranean countries; nevertheless 10.72 % of cases remain with undetermined mutation thus suggesting a potential heterogeneity of the deficiency at the molecular level. On the other hand, we note a better association of the molecular defects with the severity of the deficiency than with clinical manifestations.

  1. Contribution of haemolysis to jaundice in Sephardic Jewish glucose-6-phosphate dehydrogenase deficient neonates.

    PubMed

    Kaplan, M; Vreman, H J; Hammerman, C; Leiter, C; Abramov, A; Stevenson, D K

    1996-06-01

    We determined the contribution of haemolysis to the development of hyperbilirubinaemia in glucose-6-phosphate dehydrogenase (G-6-PD) deficient neonates and G-6-PD normal controls. Blood carboxyhaemoglobin (COHb), sampled on the third day of life, was measured by gas chromatography, corrected for inhaled carbon monoxide (COHbC), and expressed as a percentage of total haemoglobin concentration (Hb). Serum bilirubin was tested as clinically necessary. 37 non-jaundiced (peak serum total bilirubin (PSTB) < or = 255 mumol/l) and 20 jaundiced (PSTB > or = 257 mumol/l) G-6-PD-deficient neonates were compared to 31 non-jaundiced and 24 jaundiced controls with comparable PSTB values, respectively. COHbC values for the entire G-6-PD deficient group were higher than in the controls (0.75 +/- 0.17% v 0.62 +/- 0.19%, P < 0.001). COHbC and PSTB values did not correlate in the G-6-PD-deficient group (r = 0.15, P > 0.05) but did in the controls (r = 0.58, P < 0.001). COHbC values were increased to a similar extent in the G-6-PD-deficient, non-jaundiced (0.72 +/- 0.16%), the G-6-PD-deficient, jaundiced (0.80 +/- 0.19%) and the control, jaundiced (0.75 +/- 0.18%) subgroups, compared to the control, non-jaundiced subgroup (0.53 +/- 0.13%) (P < 0.05). Although present in G-6-PD deficient neonates, increased haemolysis was not directly related to the PSTB.

  2. Producing glucose 6-phosphate from cellulosic biomass: structural insights into levoglucosan bioconversion.

    PubMed

    Bacik, John-Paul; Klesmith, Justin R; Whitehead, Timothy A; Jarboe, Laura R; Unkefer, Clifford J; Mark, Brian L; Michalczyk, Ryszard

    2015-10-30

    The most abundant carbohydrate product of cellulosic biomass pyrolysis is the anhydrosugar levoglucosan (1,6-anhydro-β-d-glucopyranose), which can be converted to glucose 6-phosphate by levoglucosan kinase (LGK). In addition to the canonical kinase phosphotransfer reaction, the conversion requires cleavage of the 1,6-anhydro ring to allow ATP-dependent phosphorylation of the sugar O6 atom. Using x-ray crystallography, we show that LGK binds two magnesium ions in the active site that are additionally coordinated with the nucleotide and water molecules to result in ideal octahedral coordination. To further verify the metal binding sites, we co-crystallized LGK in the presence of manganese instead of magnesium and solved the structure de novo using the anomalous signal from four manganese atoms in the dimeric structure. The first metal is required for catalysis, whereas our work suggests that the second is either required or significantly promotes the catalytic rate. Although the enzyme binds its sugar substrate in a similar orientation to the structurally related 1,6-anhydro-N-acetylmuramic acid kinase (AnmK), it forms markedly fewer bonding interactions with the substrate. In this orientation, the sugar is in an optimal position to couple phosphorylation with ring cleavage. We also observed a second alternate binding orientation for levoglucosan, and in these structures, ADP was found to bind with lower affinity. These combined observations provide an explanation for the high Km of LGK for levoglucosan. Greater knowledge of the factors that contribute to the catalytic efficiency of LGK can be used to improve applications of this enzyme for levoglucosan-derived biofuel production. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Evaluation of the blue formazan spot test for screening glucose 6 phosphate dehydrogenase deficiency.

    PubMed

    Pujades, A; Lewis, M; Salvati, A M; Miwa, S; Fujii, H; Zarza, R; Alvarez, R; Rull, E; Corrons, J L

    1999-06-01

    Several screening tests for glucose 6 phosphate dehydrogenase (G6PD) deficiency have been reported thus far, and a standardized method of testing was proposed by the International Council for Standardization in Hematology (ICSH). The screening test used in any particular laboratory depends upon a number of factors such as cost, time required, temperature, humidity, and availability of reagents. In this study, a direct comparison between three different G6PD screening methods has been undertaken. In 71 cases (50 hematologically normal volunteers, 9 hemizygous G6PD-deficient males, and 12 heterozygous deficient females), the blue formazan spot test (BFST) was compared with the conventional methemoglobin reduction test (HiRT) and the ICSH-recommended fluorescent spot test (FST-ICSH). In all cases, the results obtained with the three screening tests were correlated with the enzyme activity assayed spectrophotometrically. In hemizygous G6PD-deficient males, all cases were equally detected with the three methods: BFST (4.7-6.64, controls: 11.1-13.4), BMRT (score +3 in all 9 cases), and FST (no fluorescence in 9 cases). In heterozygous G6PD-deficient females, two methods detected 7 out of 12 cases (BFST: 8.71-11.75, controls: 11.1-13.4; and BMRT: score +3 in 7 cases), whereas the FST-ICSH missed all 12 cases that presented a variable degree of fluorescence. Although the sensitivity for G6PD-deficient carrier detection is the same for the BMRT and the BFST, the latter has the advantage of being semiquantitative and not merely qualitative. Unfortunately, none of the three screening tests compared here allowed the detection of the 100% heterozygote carrier state of G6PD deficiency.

  4. Glucose-6-phosphate dehydrogenase enzyme stability in filter paper dried blood spots.

    PubMed

    Flores, Sharon R; Hall, Elizabeth M; De Jesús, Víctor R

    2017-10-01

    Prior to initial distribution of Glucose-6-phosphate dehydrogenase (G6PD) proficiency testing (PT) materials, we evaluated G6PD enzyme stability in dried blood spots (DBS) under various temperature and humidity environments to develop storage and usage guidelines for our new materials. We prepared fresh G6PD-normal DBS materials and conducted stability evaluations of daily use and short and long-term storage under various temperature and humidity environments. G6PD DBS PT materials retained 92% of initial activity after 30days of use at 4°C. Materials stored at -20°C and 4°C with desiccant for 30days retained 95% and 90% of initial activity, respectively. When stored for one year at -20°C or six months at 4°C specimens retained >90% of initial activity. Specimens stored at 37°C with desiccant lost 10% activity in three days. At the end of 30days, specimens stored under 'Extreme'-humidity >50% without desiccant- conditions at 37°C assayed below the NSQAP cut off for G6PD. Humidity exacerbated loss of enzyme activity with increasing temperature and time duration. Data suggest that G6PD PT materials can be stored at 4°C and used for up to one month and can be stored at -20°C for one year and yield >90% enzyme activity. Exposure to warm temperatures, especially with elevated humidity, should be avoided. Desiccant should always be used to mitigate humidity effects. Published by Elsevier Inc.

  5. Regulation of a plant SNF1-related protein kinase by glucose-6-phosphate

    SciTech Connect

    Toroser, D.; Plaut, Z.; Huber, S.C.

    2000-05-01

    One of the major protein kinases (PK{sub III}) that phosphorylates serine-158 of spinach sucrose-phosphate synthase (SPS), which is responsible for light/dark modulation of activity, is known to be a member of the SNF1-related family of protein kinases. In the present study, the authors have developed a fluorescence-based continuous assay for measurement of PK{sub III} activity. Using the continuous assay, along with the fixed-time-point {sup 32}P-incorporation assay, they demonstrate that PK{sub III} activity is inhibited by glucose-6-phosphate (Glc-6-P). Relative inhibition by Glc-6-P was increased by decreasing pH from 8.5 to 5.5 and by reducing the concentration of Mg{sup 2+} in the assay from 10 to 2 nM. Under likely physiological conditions (PH 7.0 and 2 mM Mg{sup 2+}), 10 nM Glc-6-P inhibited kinase activity approximately 70%. Inhibition by Glc-6-P could not be ascribed to contaminants in the commercial preparations. Other metabolites inhibited PK{sub III} in the following order: Glc-6-P > mannose-6-P, fructose-1,6P{sub 2} > ribose-5-P, 3-PGA, fructose-6-P. Inorganic phosphate, Glc, and AMP were not inhibitory, and free Glc did not reverse the inhibition by Glc-6-P. Because SNF1-related protein kinases are thought to function broadly in the regulation of enzyme activity and gene expression, Glc-6-P inhibition of PK{sub III} activity potentially provides a mechanism for metabolic regulation of the reactions catalyzed by these important protein kinases.

  6. Producing glucose 6-phosphate from cellulosic biomass: Structural insights into levoglucosan bioconversion

    DOE PAGES

    Bacik, John -Paul; Klesmith, Justin R.; Whitehead, Timothy A.; ...

    2015-09-09

    The most abundant carbohydrate product of cellulosic biomass pyrolysis is the anhydrosugar levoglucosan (1,6-anhydro-β-d-glucopyranose), which can be converted to glucose 6-phosphate by levoglucosan kinase (LGK). In addition to the canonical kinase phosphotransfer reaction, the conversion requires cleavage of the 1,6-anhydro ring to allow ATP-dependent phosphorylation of the sugar O6 atom. Using x-ray crystallography, we show that LGK binds two magnesium ions in the active site that are additionally coordinated with the nucleotide and water molecules to result in ideal octahedral coordination. To further verify the metal binding sites, we co-crystallized LGK in the presence of manganese instead of magnesium andmore » solved the structure de novo using the anomalous signal from four manganese atoms in the dimeric structure. The first metal is required for catalysis, whereas our work suggests that the second is either required or significantly promotes the catalytic rate. Although the enzyme binds its sugar substrate in a similar orientation to the structurally related 1,6-anhydro-N-acetylmuramic acid kinase (AnmK), it forms markedly fewer bonding interactions with the substrate. In this orientation, the sugar is in an optimal position to couple phosphorylation with ring cleavage. We also observed a second alternate binding orientation for levoglucosan, and in these structures, ADP was found to bind with lower affinity. These combined observations provide an explanation for the high Km of LGK for levoglucosan. Furthermore, greater knowledge of the factors that contribute to the catalytic efficiency of LGK can be used to improve applications of this enzyme for levoglucosan-derived biofuel production.« less

  7. Molecular Analysis of Glucose-6-Phosphate Dehydrogenase Gene Mutations in Bangladeshi Individuals

    PubMed Central

    Sarker, Suprovath Kumar; Hossain, Mohammad Amir; Qadri, Syeda Kashfi; Muraduzzaman, A. K. M.; Bhuyan, Golam Sarower; Shahidullah, Mohammod; Mannan, Mohammad Abdul; Tahura, Sarabon; Hussain, Manzoor; Akhter, Shahida; Nahar, Nazmun; Shirin, Tahmina; Qadri, Firdausi; Mannoor, Kaiissar

    2016-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common X-linked human enzyme defect of red blood cells (RBCs). Individuals with this gene defect appear normal until exposed to oxidative stress which induces hemolysis. Consumption of certain foods such as fava beans, legumes; infection with bacteria or virus; and use of certain drugs such as primaquine, sulfa drugs etc. may result in lysis of RBCs in G6PD deficient individuals. The genetic defect that causes G6PD deficiency has been identified mostly as single base missense mutations. One hundred and sixty G6PD gene mutations, which lead to amino acid substitutions, have been described worldwide. The purpose of this study was to detect G6PD gene mutations in hospital-based settings in the local population of Dhaka city, Bangladesh. Qualitative fluorescent spot test and quantitative enzyme activity measurement using RANDOX G6PDH kit were performed for analysis of blood specimens and detection of G6PD-deficient participants. For G6PD-deficient samples, PCR was done with six sets of primers specific for G6PD gene. Automated Sanger sequencing of the PCR products was performed to identify the mutations in the gene. Based on fluorescence spot test and quantitative enzyme assay followed by G6PD gene sequencing, 12 specimens (11 males and one female) among 121 clinically suspected patient-specimens were found to be deficient, suggesting a frequency of 9.9% G6PD deficiency. Sequencing of the G6PD-deficient samples revealed c.C131G substitution (exon-3: Ala44Gly) in six samples, c.G487A substitution (exon-6:Gly163Ser) in five samples and c.G949A substitution (exon-9: Glu317Lys) of coding sequence in one sample. These mutations either affect NADP binding or disrupt protein structure. From the study it appears that Ala44Gly and Gly163Ser are the most common G6PD mutations in Dhaka, Bangladesh. This is the first study of G6PD mutations in Bangladesh. PMID:27880809

  8. Glucose 6-phosphate dehydrogenase deficiency enhances germ cell apoptosis and causes defective embryogenesis in Caenorhabditis elegans.

    PubMed

    Yang, H-C; Chen, T-L; Wu, Y-H; Cheng, K-P; Lin, Y-H; Cheng, M-L; Ho, H-Y; Lo, S J; Chiu, D T-Y

    2013-05-02

    Glucose 6-phosphate dehydrogenase (G6PD) deficiency, known as favism, is classically manifested by hemolytic anemia in human. More recently, it has been shown that mild G6PD deficiency moderately affects cardiac function, whereas severe G6PD deficiency leads to embryonic lethality in mice. How G6PD deficiency affects organisms has not been fully elucidated due to the lack of a suitable animal model. In this study, G6PD-deficient Caenorhabditis elegans was established by RNA interference (RNAi) knockdown to delineate the role of G6PD in animal physiology. Upon G6PD RNAi knockdown, G6PD activity was significantly hampered in C. elegans in parallel with increased oxidative stress and DNA oxidative damage. Phenotypically, G6PD-knockdown enhanced germ cell apoptosis (2-fold increase), reduced egg production (65% of mock), and hatching (10% of mock). To determine whether oxidative stress is associated with G6PD knockdown-induced reproduction defects, C. elegans was challenged with a short-term hydrogen peroxide (H2O2). The early phase egg production of both mock and G6PD-knockdown C. elegans were significantly affected by H2O2. However, H2O2-induced germ cell apoptosis was more dramatic in mock than that in G6PD-deficient C. elegans. To investigate the signaling pathways involved in defective oogenesis and embryogenesis caused by G6PD knockdown, mutants of p53 and mitogen-activated protein kinase (MAPK) pathways were examined. Despite the upregulation of CEP-1 (p53), cep-1 mutation did not affect egg production and hatching in G6PD-deficient C. elegans. Neither pmk-1 nor mek-1 mutation significantly affected egg production, whereas sek-1 mutation further decreased egg production in G6PD-deficient C. elegans. Intriguingly, loss of function of sek-1 or mek-1 dramatically rescued defective hatching (8.3- and 9.6-fold increase, respectively) induced by G6PD knockdown. Taken together, these findings show that G6PD knockdown reduces egg production and hatching in C. elegans

  9. Prevalence and Molecular Characterization of Glucose-6-Phosphate Dehydrogenase Deficiency at the China-Myanmar Border.

    PubMed

    Li, Qing; Yang, Fang; Liu, Rong; Luo, Lan; Yang, Yuling; Zhang, Lu; Liu, Huaie; Zhang, Wen; Fan, Zhixiang; Yang, Zhaoqing; Cui, Liwang; He, Yongshu

    2015-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked hereditary disease that predisposes red blood cells to oxidative damage. G6PD deficiency is particularly prevalent in historically malaria-endemic areas. Use of primaquine for malaria treatment may result in severe hemolysis in G6PD deficient patients. In this study, we systematically evaluated the prevalence of G6PD deficiency in the Kachin (Jingpo) ethnic group along the China-Myanmar border and determined the underlying G6PD genotypes. We surveyed G6PD deficiency in 1770 adult individuals (671 males and 1099 females) of the Kachin ethnicity using a G6PD fluorescent spot test. The overall prevalence of G6PD deficiency in the study population was 29.6% (523/1770), among which 27.9% and 30.6% were males and females, respectively. From these G6PD deficient samples, 198 unrelated individuals (147 females and 51 males) were selected for genotyping at 11 known G6PD single nucleotide polymorphisms (SNPs) in Southeast Asia (ten in exons and one in intron 11) using a multiplex SNaPshot assay. Mutations with known association to a deficient phenotype were detected in 43.9% (87/198) of cases, intronic and synonymous mutations were detected alone in 34.8% (69/198) cases and no mutation were found in 21.2% (42/198) cases. Five non-synonymous mutations, Mahidol 487G>A, Kaiping 1388G>A, Canton 1376G>T, Chinese 4 392G>T, and Viangchan 871G>A were detected. Of the 87 cases with known deficient mutations, the Mahidol variant was the most common (89.7%; 78/87), followed by the Kaiping (8.0%; 7/87) and the Viangchan (2.2%; 2/87) variants. The Canton and Chinese 4 variants were found in 1.1% of these 87 cases. Among them, two females carried the Mahidol/Viangchan and Mahidol/Kaiping double mutations, respectively. Interestingly, the silent SNPs 1311C>T and IVS11nt93T>C both occurred in the same 95 subjects with frequencies at 56.4% and 23.5% in tested females and males, respectively (P<0.05). It is noteworthy that 24

  10. [Significance of glucose-6-phosphate isomerase assay in early diagnosis of rheumatoid arthritis].

    PubMed

    Xu, J; Liu, J; Zhu, L; Zhang, X W; Li, Z G

    2016-12-18

    To explore the titer of glucose-6-phosphate isomerase (GPI) for early diagnosis of the outpatient with rheumatoid arthritis (RA) in real life, and to analyze its relationship with disease activity. In the study, 1 051 patients with arthritis were collected in the group who had joints tender and swelling, and 90 cases of healthy people as a control group. ELISA method was used to detect the serum level of GPI, and according to clinical features and laboratory test, all the patients including 525 RA patients, the other patients including osteoarthritis (OA), 134 cases of seronegative spine joint disease (SpA), 104 cases of systemic lupus erythematosus (SLE), 31 cases of primary Sjogren syndrome (pSS), 24 cases of gout arthritis (GA), 22 cases of other connective tissue diseases (including polymyalgia rheumatica, dermatomyositis, systemic sclerosis, adult Still disease) and 46 cases of other diseases (including 165 cases of osteoporosis, avascular necrosis of the femoral head, traumatic osteomyelitis, bone and joint disease, juvenile rheumatoid arthritis, tumor). The diagnostic values of GPI were assessed, and the differences between the GPI positive and negative groups of the RA patients in clinical characteristics, disease activity, severity and inflammatory index analyzed. The positive rate of serum GPI in the patients with RA was 55.4%, contrasting to other autoimmune diseases (14.3%) and healthy controls (7.78%)(P<0.001). Compared with the OA and SpA patients, the RA group was increased more significantly, and the difference was statistically significant (P<0.001). The diagnostic value of GPI alone for RA was 0.39 mg/L, the sensitivity was 54.2%, and specificity was 87.3%. The positive rate of GPI in RF negative patients was 36.1%; the positive rate of GPI in anti-CCP antibody negative patients was 34.2%; the positive rate of GPI in RF and anti-CCP antibody negative patients was 24.1%. The level of GPI had positive correlation (P<0.05) with ESR, RF, anti

  11. Glucose-6-phosphate dehydrogenase deficiency among malaria suspects attending Gambella hospital, southwest Ethiopia.

    PubMed

    Tsegaye, Arega; Golassa, Lemu; Mamo, Hassen; Erko, Berhanu

    2014-11-18

    Glucose-6-phosphate dehydrogenase deficiency (G6PDd) is widespread across malaria endemic regions. G6PD-deficient individuals are at risk of haemolysis when exposed, among other agents, to primaquine and tafenoquine, which are capable of blocking malaria transmission by killing Plasmodium falciparum gametocytes and preventing Plasmodium vivax relapses by targeting hypnozoites. It is evident that no measures are currently in place to ensure safe delivery of these drugs within the context of G6PDd risk. Thus, determining G6PDd prevalence in malarious areas would contribute towards avoiding possible complications in malaria elimination using the drugs. This study, therefore, was aimed at determining G6PDd prevalence in Gambella hospital, southwest Ethiopia, using CareStart™ G6PDd fluorescence spot test. Venous blood samples were collected from febrile patients (n = 449) attending Gambella hospital in November-December 2013. Malaria was diagnosed using blood films and G6PDd was screened using CareStart™ G6PDd screening test (Access Bio, New Jersey, USA). Haematological parameters were also measured. The association of G6PD phenotype with sex, ethnic group and malaria smear positivity was tested. Malaria prevalence was 59.2% (96.6% of the cases being P. falciparum mono infections). Totally 33 participants (7.3%) were G6PD-deficient with no significant difference between the sexes. The chance of being G6PD-deficient was significantly higher for the native ethnic groups (Anuak and Nuer) compared to the 'highlanders'/settlers (odds ratio (OD) = 3.9, 95% confidence interval (CI) 0.481-31.418 for Anuak vs 'highlanders'; OD = 4.9, 95% CI 0.635-38.00 for Nuer vs 'highlanders'). G6PDd prevalence among the Nuer (14.3%) was significantly higher than that for the Anuak (12.0%). G6PDd prevalence in the area is substantial with 30 (90.9%) of the 33 deficient individuals having malaria suggesting the non-protective role of the disorder at least from clinical malaria

  12. Glucose-6-phosphate dehydrogenase polymorphisms and susceptibility to mild malaria in Dogon and Fulani, Mali.

    PubMed

    Maiga, Bakary; Dolo, Amagana; Campino, Susana; Sepulveda, Nuno; Corran, Patrick; Rockett, Kirk A; Troye-Blomberg, Marita; Doumbo, Ogobara K; Clark, Taane G

    2014-07-11

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is associated with protection from severe malaria, and potentially uncomplicated malaria phenotypes. It has been documented that G6PD deficiency in sub-Saharan Africa is due to the 202A/376G G6PD A-allele, and association studies have used genotyping as a convenient technique for epidemiological studies. However, recent studies have shown discrepancies in G6PD202/376 associations with severe malaria. There is evidence to suggest that other G6PD deficiency alleles may be common in some regions of West Africa, and that allelic heterogeneity could explain these discrepancies. A cross-sectional epidemiological study of malaria susceptibility was conducted during 2006 and 2007 in the Sahel meso-endemic malaria zone of Mali. The study included Dogon (n = 375) and Fulani (n = 337) sympatric ethnic groups, where the latter group is characterized by lower susceptibility to Plasmodium falciparum malaria. Fifty-three G6PD polymorphisms, including 202/376, were genotyped across the 712 samples. Evidence of association of these G6PD polymorphisms and mild malaria was assessed in both ethnic groups using genotypic and haplotypic statistical tests. It was confirmed that the Fulani are less susceptible to malaria, and the 202A mutation is rare in this group (<1% versus Dogon 7.9%). The Betica-Selma 968C/376G (~11% enzymatic activity) was more common in Fulani (6.1% vs Dogon 0.0%). There are differences in haplotype frequencies between Dogon and Fulani, and association analysis did not reveal strong evidence of protective G6PD genetic effects against uncomplicated malaria in both ethnic groups and gender. However, there was some evidence of increased risk of mild malaria in Dogon with the 202A mutation, attaining borderline statistical significance in females. The rs915942 polymorphism was found to be associated with asymptomatic malaria in Dogon females, and the rs61042368 polymorphism was associated with clinical malaria in

  13. Glucose-6-phosphate dehydrogenase polymorphisms and susceptibility to mild malaria in Dogon and Fulani, Mali

    PubMed Central

    2014-01-01

    Background Glucose-6-phosphate dehydrogenase (G6PD) deficiency is associated with protection from severe malaria, and potentially uncomplicated malaria phenotypes. It has been documented that G6PD deficiency in sub-Saharan Africa is due to the 202A/376G G6PD A-allele, and association studies have used genotyping as a convenient technique for epidemiological studies. However, recent studies have shown discrepancies in G6PD202/376 associations with severe malaria. There is evidence to suggest that other G6PD deficiency alleles may be common in some regions of West Africa, and that allelic heterogeneity could explain these discrepancies. Methods A cross-sectional epidemiological study of malaria susceptibility was conducted during 2006 and 2007 in the Sahel meso-endemic malaria zone of Mali. The study included Dogon (n = 375) and Fulani (n = 337) sympatric ethnic groups, where the latter group is characterized by lower susceptibility to Plasmodium falciparum malaria. Fifty-three G6PD polymorphisms, including 202/376, were genotyped across the 712 samples. Evidence of association of these G6PD polymorphisms and mild malaria was assessed in both ethnic groups using genotypic and haplotypic statistical tests. Results It was confirmed that the Fulani are less susceptible to malaria, and the 202A mutation is rare in this group (< 1% versus Dogon 7.9%). The Betica-Selma 968C/376G (~11% enzymatic activity) was more common in Fulani (6.1% vs Dogon 0.0%). There are differences in haplotype frequencies between Dogon and Fulani, and association analysis did not reveal strong evidence of protective G6PD genetic effects against uncomplicated malaria in both ethnic groups and gender. However, there was some evidence of increased risk of mild malaria in Dogon with the 202A mutation, attaining borderline statistical significance in females. The rs915942 polymorphism was found to be associated with asymptomatic malaria in Dogon females, and the rs61042368 polymorphism was

  14. Lysine-21 of Leuconostoc mesenteroides glucose 6-phosphate dehydrogenase participates in substrate binding through charge-charge interaction.

    PubMed Central

    Lee, W. T.; Levy, H. R.

    1992-01-01

    Leuconostoc mesenteroides glucose 6-phosphate dehydrogenase (G6PD) was isolated in high yield and purified to homogeneity from a newly constructed strain of Escherichia coli which lacks its own glucose 6-phosphate dehydrogenase gene. Lys-21 is one of two lysyl residues in the enzyme previously modified by the affinity labels pyridoxal 5'-phosphate and pyridoxal 5'-diphosphate-5'-adenosine, which are competitive inhibitors of the enzyme with respect to glucose 6-phosphate (LaDine, J.R., Carlow, D., Lee, W.T., Cross, R.L., Flynn, T.G., & Levy, H.R., 1991, J. Biol. Chem. 266, 5558-5562). K21R and K21Q mutants of the enzyme were purified to homogeneity and characterized kinetically to determine the function of Lys-21. Both mutant enzymes showed increased Km-values for glucose 6-phosphate compared to wild-type enzyme: 1.4-fold (NAD-linked reaction) and 2.1-fold (NADP-linked reaction) for the K21R enzyme, and 36-fold (NAD-linked reaction) and 53-fold (NADP-linked reaction) for the K21Q enzyme. The Km for NADP+ was unchanged in both mutant enzymes. The Km for NAD+ was increased 1.5- and 3.2-fold, compared to the wild-type enzyme, in the K21R and K21Q enzymes, respectively. For the K21R enzyme the kcat for the NAD- and NADP-linked reactions was unchanged. The kcat for the K21Q enzyme was increased in the NAD-linked reaction by 26% and decreased by 30% in the NADP-linked reaction from the values for the wild-type enzyme. The data are consistent with Lys-21 participating in the binding of the phosphate group of the substrate to the enzyme via charge-charge interaction. PMID:1304341

  15. [Adaptogenic effect of the vitamin D3 containing supplement "videchol" on glucose-6-phosphate dehydrogenase activity in erythrone of irradiated rats].

    PubMed

    Becerril Aragon, G A; Starykovych, L S; Kolodkin, A; Horot', I V; Velykyĭ, M M

    2007-01-01

    Two fast migrating, major, multiple molecular forms (MMF) of glucose-6-phosphate dehydrogenase [EC:1.1.1.49]: G-6-PDH-1 and G-6-PDH-2, and two minor forms: G-6-PDH-3 and G-6-PDH-4 were revealed in the electrophoregrams of both erythrocytes haemolisates as well in the homogenates of bone marrow cellular lines of rats at control conditions. Daily 1 cGy irradiation of rats up to a cumulative dose of 20 cGy led to a drop of G-6-PDH total activity and it caused a redistribution of the MMF of the enzyme in bone marrow cellular populations. However, G-6-PDH activity in erythrocytes exceeded the control means in all the experimental terms. The calculation of the local redistribution coefficient (l(G-6-FDH-i)) showed that these changes are mainly determined by the increase of the activity of the isoform G-6-PDH-3. Vitamin D3 administration to rats generated a correction of G-6-PDH activity in all studied cellular populations. Meanwhile, the MMF profiles were characterized by multidirectional rearrangements in the bone marrow erythroid and granulocyte-monocyte cells and in erythrocytes. The specificity of changes in the distribution of the MMF of G-6-PDH in the three studied cellular populations depends on the particularities of their energetic metabolism at irradiation conditions and on the modifying action of the natural adaptogen 1,25-dihydroxicholecalciferol.

  16. Lowering effect of firefly squid powder on triacylglycerol content and glucose-6-phosphate dehydrogenase activity in rat liver.

    PubMed

    Takeuchi, Hiroyuki; Morita, Ritsuko; Shirai, Yoko; Nakagawa, Yoshihisa; Terashima, Teruya; Ushikubo, Shun; Matsuo, Tatsuhiro

    2014-01-01

    Effects of dietary firefly squid on serum and liver lipid levels were investigated. Male Wistar rats were fed a diet containing 5% freeze-dried firefly squid or Japanese flying squid for 2 weeks. There was no significant difference in the liver triacylglycerol level between the control and Japanese flying squid groups, but the rats fed the firefly squid diet had a significantly lower liver triacylglycerol content than those fed the control diet. No significant difference was observed in serum triacylglycerol levels between the control and firefly squid groups. The rats fed the firefly squid had a significantly lower activity of liver glucose-6-phosphate dehydrogenase compared to the rats fed the control diet. There was no significant difference in liver fatty acid synthetase activity among the three groups. Hepatic gene expression and lipogenic enzyme activity were investigated; a DNA microarray showed that the significantly enriched gene ontology category of down-regulated genes in the firefly squid group was "lipid metabolic process". The firefly squid group had lower mRNA level of glucose-6-phosphate dehydrogenase compared to the controls. These results suggest that an intake of firefly squid decreases hepatic triacylglycerol in rats, and the reduction of mRNA level and enzyme activity of glucose-6-phosphate dehydrogenase might be related to the mechanisms.

  17. The Production and Utilization of GDP-glucose in the Biosynthesis of Trehalose 6-Phosphate by Streptomyces venezuelae.

    PubMed

    Asención Diez, Matías D; Miah, Farzana; Stevenson, Clare E M; Lawson, David M; Iglesias, Alberto A; Bornemann, Stephen

    2017-01-20

    Trehalose-6-phosphate synthase OtsA from streptomycetes is unusual in that it uses GDP-glucose as the donor substrate rather than the more commonly used UDP-glucose. We now confirm that OtsA from Streptomyces venezuelae has such a preference for GDP-glucose and can utilize ADP-glucose to some extent too. A crystal structure of the enzyme shows that it shares twin Rossmann-like domains with the UDP-glucose-specific OtsA from Escherichia coli However, it is structurally more similar to Streptomyces hygroscopicus VldE, a GDP-valienol-dependent pseudoglycosyltransferase enzyme. Comparison of the donor binding sites reveals that the amino acids associated with the binding of diphosphoribose are almost all identical in these three enzymes. By contrast, the amino acids associated with binding guanine in VldE (Asn, Thr, and Val) are similar in S. venezuelae OtsA (Asp, Ser, and Phe, respectively) but not conserved in E. coli OtsA (His, Leu, and Asp, respectively), providing a rationale for the purine base specificity of S. venezuelae OtsA. To establish which donor is used in vivo, we generated an otsA null mutant in S. venezuelae The mutant had a cell density-dependent growth phenotype and accumulated galactose 1-phosphate, glucose 1-phosphate, and GDP-glucose when grown on galactose. To determine how the GDP-glucose is generated, we characterized three candidate GDP-glucose pyrophosphorylases. SVEN_3027 is a UDP-glucose pyrophosphorylase, SVEN_3972 is an unusual ITP-mannose pyrophosphorylase, and SVEN_2781 is a pyrophosphorylase that is capable of generating GDP-glucose as well as GDP-mannose. We have therefore established how S. venezuelae can make and utilize GDP-glucose in the biosynthesis of trehalose 6-phosphate.

  18. The Production and Utilization of GDP-glucose in the Biosynthesis of Trehalose 6-Phosphate by Streptomyces venezuelae*

    PubMed Central

    Asención Diez, Matías D.; Miah, Farzana; Stevenson, Clare E. M.; Lawson, David M.; Iglesias, Alberto A.; Bornemann, Stephen

    2017-01-01

    Trehalose-6-phosphate synthase OtsA from streptomycetes is unusual in that it uses GDP-glucose as the donor substrate rather than the more commonly used UDP-glucose. We now confirm that OtsA from Streptomyces venezuelae has such a preference for GDP-glucose and can utilize ADP-glucose to some extent too. A crystal structure of the enzyme shows that it shares twin Rossmann-like domains with the UDP-glucose-specific OtsA from Escherichia coli. However, it is structurally more similar to Streptomyces hygroscopicus VldE, a GDP-valienol-dependent pseudoglycosyltransferase enzyme. Comparison of the donor binding sites reveals that the amino acids associated with the binding of diphosphoribose are almost all identical in these three enzymes. By contrast, the amino acids associated with binding guanine in VldE (Asn, Thr, and Val) are similar in S. venezuelae OtsA (Asp, Ser, and Phe, respectively) but not conserved in E. coli OtsA (His, Leu, and Asp, respectively), providing a rationale for the purine base specificity of S. venezuelae OtsA. To establish which donor is used in vivo, we generated an otsA null mutant in S. venezuelae. The mutant had a cell density-dependent growth phenotype and accumulated galactose 1-phosphate, glucose 1-phosphate, and GDP-glucose when grown on galactose. To determine how the GDP-glucose is generated, we characterized three candidate GDP-glucose pyrophosphorylases. SVEN_3027 is a UDP-glucose pyrophosphorylase, SVEN_3972 is an unusual ITP-mannose pyrophosphorylase, and SVEN_2781 is a pyrophosphorylase that is capable of generating GDP-glucose as well as GDP-mannose. We have therefore established how S. venezuelae can make and utilize GDP-glucose in the biosynthesis of trehalose 6-phosphate. PMID:27903647

  19. Sub-Saharan red cell antigen phenotypes and glucose-6-phosphate dehydrogenase deficiency variants in French Guiana.

    PubMed

    Petit, Florence; Bailly, Pascal; Chiaroni, Jacques; Mazières, Stéphane

    2016-06-07

    The treatment of Plasmodium vivax infections requires the use of primaquine, which can lead to severe haemolysis in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals. However, most of the Latin American countries, which are still endemic for vivax malaria, lack information on the distribution of G6PD deficiency (G6PDd). No survey has been performed so far in French Guiana. Herein, 80 individuals of the French Guianan Noir Marron population were scrutinized for red cell surface antigens of six blood group systems (ABO, Rh, Kell, Kidd, Duffy and MNS) and G6PD genetic polymorphisms. First, the sub-Saharan origin of the red cell phenotypes was assessed in relation with the literature. Then, given that the main sub-Saharan G6PDd variants are expected to be encountered, only the G6PD sequences of exons 4, 5, 6 and 9 were screened. This work aims at appraising the G6PD gene variation in this population, and thus, contributing to the G6PD piecemeal information in Latin America. Ninety-seven percent (97 %) of the red cells are Fy(a- b-), either D+ C- E- c+ e+ or D+ C+ E- c+ e+ and 44 % exhibited the Fya-/Jkb-/S- combined phenotype. Noteworthy is the detection of the G6PD(Val68Met) variant characterized by c.202G > A transition, G6PD(Asn126Asp) variant characterized by c.376A>G transition and G6PD(Asp181Val) variant characterized by c.542A>T transversion of the G6PD gene in 22.5 % of the sample, characteristic of the A(-(202)), A and Santamaria G6PDd variants, respectively. French Guianan Noir Marron population represents a pool of Rh-D antigen positive, Duffy-negative and G6PD-deficient erythrocytes, the latter accounting for one in every eight persons. The present study provides the first community-based estimation of the frequency of G6PDd polymorphisms in French Guiana. These results contribute to the G6PD genetic background information puzzle in Latin America.

  20. Glucose-6-phosphate dehydrogenase deficiency in people living in malaria endemic districts of Nepal.

    PubMed

    Ghimire, Prakash; Singh, Nihal; Ortega, Leonard; Rijal, Komal Raj; Adhikari, Bipin; Thakur, Garib Das; Marasini, Baburam

    2017-05-23

    Glucose-6-phosphate dehydrogenase (G6PD) is a rate limiting enzyme of the pentose phosphate pathway and is closely associated with the haemolytic disorders among patients receiving anti-malarial drugs, such as primaquine. G6PD deficiency (G6PDd) is an impending factor for radical treatment of malaria which affects the clearance of gametocytes from the blood and subsequent delay in the achievement of malaria elimination. The main objective of this study was to assess the prevalence of G6PD deficiency in six malaria endemic districts in Southern Nepal. A cross-sectional population based prevalence survey was conducted in six malaria endemic districts of Nepal, during April-Dec 2013. A total of 1341 blood samples were tested for G6PDd using two different rapid diagnostic test kits (Binax-Now(®) and Care Start™). Equal proportions of participants from each district (n ≥ 200) were enrolled considering ethnic and demographic representation of the population groups. Out of total 1341 blood specimens collected from six districts, the overall prevalence of G6PDd was 97/1341; 7.23% on Binax Now and 81/1341; 6.0% on Care Start test. Higher prevalence was observed in male than females [Binax Now: male 10.2%; 53/521 versus female 5.4%; 44/820 (p = 0.003) and Care Start: male 8.4%; 44/521 versus female 4.5%; 37/820 (p = 0.003)]. G6PDd was higher in ethnic groups Rajbanshi (11.7%; 19/162) and Tharu (5.6%; 56/1005) (p = 0.006), major inhabitant of the endemic districts. Higher prevalence of G6PDd was found in Jhapa (22/224; 9.8%) and Morang districts (18/225; 8%) (p = 0.031). In a multivariate analysis, male were found at more risk for G6PDd than females, on Binax test (aOR = 1.97; CI 1.28-3.03; p = 0.002) and Care Start test (aOR = 1.86; CI 1.16-2.97; p = 0.009). The higher prevalence of G6PDd in certain ethnic group, gender and geographical region clearly demonstrates clustering of the cases and ascertained the risk groups within the population. This is

  1. [Significance of antibodies to the citrullinated glucose-6-phosphate isomerase peptides in rheumatoid arthritis].

    PubMed

    Wu, D; Sun, L; Li, C H; Yang, L; Zhao, J X; Liu, X Y

    2016-12-18

    To detect the anti-citrullinated glucose-6-phosphate isomerase (GPI) 70-88 peptide antibody (anti-C-GPI(70-88) antibody), anti-citrullinated GPI 435-453 peptide antibody (anti-C-GPI(435-453) antibody), anti-GPI 70-88 peptide antibody (anti-GPI(70-88) antibody) and anti-GPI 435-453 peptide antibody(anti-GPI(435-453) antibody) in the serum of rheumatoid arthritis (RA) patients, and examine the diagnostic values of the anti-C-GPI peptide antibodies in RA. The anti-C-GPI(70-88) antibody, anti-C-GPI(435-453) antibody, anti-GPI(70-88) antibody and anti-GPI(435-453) antibody were detected by enzyme-linked immunosorbent assay (ELISA) in 191 RA patients, 129 other rheumatic diseases and 74 healthy controls. The clinical and laboratory data of the patients with RA were collected, and the values of anti-C-GPI peptide antibodies in the diagnosis of RA and the relationships of anti-C-GPI peptide antibodies with the clinical and laboratory parameters analyzed. (1) The mean titers of the anti-C-GPI(70-88) antibody and the anti-C-GPI(435-453) antibody in the RA patients (respectively, 68.71 ± 4.20 and 51.78 ± 3.13) were significantly higher than those with other rheumatic diseases and healthy individuals (P <0.05). However, the mean titers of the anti-GPI(70-88) antibody and anti-GPI(435-453) antibody in the RA patients were similar to those with other rheumatic diseases and healthy individuals. (2) The diagnostic sensitivity and specificity of the anti-C-GPI(70-88) antibody for RA were 41.88% and 84.50% respectively; and the diagnostic sensitivity and specificity of the anti-C-GPI(435-453) antibody for RA were 46.05% and 86.05% respectively. The sensitivity of combined detection of the two anti-C-GPI peptide antibodies was 50.79%, and the specificity was 81.40%. (3) The positive rates of the anti-C-GPI(70-88) antibody and the anti-C-GPI(435-453) antibody were 35% and 45% respectively in those patients with negative anti-cyclic citrullinated peptide antibody, anti

  2. Purification and investigation of some kinetic properties of glucose-6-phosphate dehydrogenase from parsley (Petroselinum hortense) leaves.

    PubMed

    Coban, T Abdül Kadir; Ciftçi, Mehmet; Küfrevioğlu, O Irfan

    2002-05-01

    In this study, glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate: NADP+ oxidoreductase, EC 1.1.1.49; G6PD) was purified from parsley (Petroselinum hortense) leaves, and analysis of the kinetic behavior and some properties of the enzyme were investigated. The purification consisted of three steps: preparation of homogenate, ammonium sulfate fractionation, and DEAE-Sephadex A50 ion exchange chromatography. The enzyme was obtained with a yield of 8.79% and had a specific activity of 2.146 U (mg protein)(-1). The overall purification was about 58-fold. Temperature of +4 degrees C was maintained during the purification process. Enzyme activity was spectrophotometrically measured according to the Beutler method, at 340 nm. In order to control the purification of enzyme, SDS-polyacrylamide gel electrophoresis was carried out in 4% and 10% acrylamide for stacking and running gel, respectively. SDS-polyacrylamide gel electrophoresis showed a single band for enzyme. The molecular weight was found to be 77.6 kDa by Sephadex G-150 gel filtration chromatography. A protein band corresponding to a molecular weight of 79.3 kDa was obtained on SDS-polyacrylamide gel electrophoresis. For the enzymes, the stable pH, optimum pH, and optimum temperature were found to be 6.0, 8.0, and 60 degrees C, respectively. Moreover, KM and Vmax values for NADP+ and G6-P at optimum pH and 25 degrees C were determined by means of Lineweaver-Burk graphs. Additionally, effects of streptomycin sulfate and tetracycline antibiotics were investigated for the enzyme activity of glucose-6-phosphate dehydrogenase in vitro.

  3. Glucose 6-phosphate dehydrogenase is required for sucrose and trehalose to be efficient osmoprotectants in Sinorhizobium meliloti.

    PubMed

    Barra, Lise; Pica, Nathalie; Gouffi, Kamila; Walker, Graham C; Blanco, Carlos; Trautwetter, Annie

    2003-12-12

    Inactivation of the zwf gene in Sinorhizobium meliloti induces an osmosensitive phenotype and the loss of osmoprotection by trehalose and sucrose, but not by ectoine and glycine betaine. This phenotype is not linked to a defect in the biosynthesis of endogenous solutes. zwf expression is induced by high osmolarity, sucrose and trehalose, but is repressed by betaine. A zwf mutant is more sensitive than its parental strain to superoxide ions, suggesting that glucose 6-phosphate dehydrogenase involvement in the osmotic response most likely results from the production of reactive oxygen species during osmotic stress.

  4. The Preterm Infant: A High-Risk Situation for Neonatal Hyperbilirubinemia Due to Glucose-6-Phosphate Dehydrogenase Deficiency.

    PubMed

    Kaplan, Michael; Hammerman, Cathy; Bhutani, Vinod K

    2016-06-01

    Prematurity and glucose-6-phosphate dehydrogenase (G6PD) deficiency are risk factors for neonatal hyperbilirubinemia. The 2 conditions may interact additively or synergistically, contributing to extreme hyperbilirubinemia, with the potential for bilirubin neurotoxicity. This hyperbilirubinemia is the result of sudden, unpredictable, and acute episodes of hemolysis in combination with immaturity of bilirubin elimination, primarily of conjugation. Avoidance of contact with known triggers of hemolysis in G6PD-deficient individuals will prevent some, but not all, episodes of hemolysis. All preterm infants with G6PD deficiency should be vigilantly observed for the development of jaundice both in hospital and after discharge home.

  5. Mutational Analyses of Glucose Dehydrogenase and Glucose-6-Phosphate Dehydrogenase Genes in Pseudomonas fluorescens Reveal Their Effects on Growth and Alginate Production.

    PubMed

    Maleki, Susan; Mærk, Mali; Valla, Svein; Ertesvåg, Helga

    2015-05-15

    The biosynthesis of alginate has been studied extensively due to the importance of this polymer in medicine and industry. Alginate is synthesized from fructose-6-phosphate and thus competes with the central carbon metabolism for this metabolite. The alginate-producing bacterium Pseudomonas fluorescens relies on the Entner-Doudoroff and pentose phosphate pathways for glucose metabolism, and these pathways are also important for the metabolism of fructose and glycerol. In the present study, the impact of key carbohydrate metabolism enzymes on growth and alginate synthesis was investigated in P. fluorescens. Mutants defective in glucose-6-phosphate dehydrogenase isoenzymes (Zwf-1 and Zwf-2) or glucose dehydrogenase (Gcd) were evaluated using media containing glucose, fructose, or glycerol. Zwf-1 was shown to be the most important glucose-6-phosphate dehydrogenase for catabolism. Both Zwf enzymes preferred NADP as a coenzyme, although NAD was also accepted. Only Zwf-2 was active in the presence of 3 mM ATP, and then only with NADP as a coenzyme, indicating an anabolic role for this isoenzyme. Disruption of zwf-1 resulted in increased alginate production when glycerol was used as the carbon source, possibly due to decreased flux through the Entner-Doudoroff pathway rendering more fructose-6-phosphate available for alginate biosynthesis. In alginate-producing cells grown on glucose, disruption of gcd increased both cell numbers and alginate production levels, while this mutation had no positive effect on growth in a non-alginate-producing strain. A possible explanation is that alginate synthesis might function as a sink for surplus hexose phosphates that could otherwise be detrimental to the cell.

  6. Protective effects of glucose-6-phosphate and NADP against alpha-chaconine-induced developmental toxicity in Xenopus embryos.

    PubMed

    Rayburn, J R; Bantle, J A; Qualls, C W; Friedman, M

    1995-12-01

    In previous studies a metabolic activation system (MAS) composed of Aroclor 1254-induced rat liver microsomes led to an apparent reduction of potato glycoalkaloid developmental toxicity in the frog embryo teratogenesis assay-Xenopus (FETAX). The reasons for this reduction were investigated in this study. The effect of the exogenous MAS on glycoalkaloid developmental toxicity was examined in two experiments in which a concentration series of alpha-chaconine was tested with a MAS with and without a reduced nicotinamide adenine dinucleotide (NADPH) generator system consisting of NADPH, oxidized nicotinamide adenine dinucleotide (NADP), glucose-6-phosphate (G6P) and glucose-6-phosphate dehydrogenase. The NADPH generator system and each of its individual components were tested at a single high concentration of alpha-chaconine to evaluate their potential effects on toxicity. The findings indicated that the protective effect of the MAS was not the result of detoxification by microsomal enzyme systems, but was caused by two components of the NADPH generator system, namely NADP and G6P. G6P was more protective of alpha-chaconine-induced toxicity than NADP at the concentrations tested. Thus, FETAX with a MAS must be performed with appropriate controls that take into account the possible interactions with individual components of the system.

  7. Amperometric biosensor based on Prussian Blue nanoparticle-modified screen-printed electrode for estimation of glucose-6-phosphate.

    PubMed

    Banerjee, Suchanda; Sarkar, Priyabrata; Turner, Anthony P F

    2013-08-15

    Glucose-6-phosphate (G6P) plays an important role in carbohydrate metabolism of all living organisms. Compared with the conventional analytical methods available for estimation of G6P, the biosensors having relative simplicity, specificity, low cost, and fast response time are a promising alternative. We have reported a G6P biosensor based on screen-printed electrode using Prussian Blue (PB) nanoparticles and enzymes, glucose-6-phosphate dehydrogenase, and glutathione reductase. The PB nanoparticles acted as a mediator and thereby enhanced the rate of electron transfer in a bienzymatic reaction. The Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy study confirmed the formation of PB, whereas atomic force microscopy revealed that PB nanoparticles were approximately 25 to 30 nm in diameter. Various optimization studies, such as pH, enzyme, and cofactor loading, were conducted to obtain maximum amperometric responses for G6P measurement. The developed G6P biosensor showed a broad linear response in the range of 0.01 to 1.25 mM, with a detection limit of 2.3 μM and sensitivity of 63.3 μA/mM at a signal-to-noise ratio of 3 within 15s at an applied working potential of -100 mV. The proposed G6P biosensor also exhibited good stability and excellent anti-interference ability, and it worked well for serum samples. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Glucose-6-phosphate dehydrogenase deficiency and risk of colorectal cancer in Northern Sardinia: A retrospective observational study.

    PubMed

    Dore, Maria P; Davoli, Agnese; Longo, Nunzio; Marras, Giuseppina; Pes, Giovanni M

    2016-11-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency has been associated with a lower cancer risk, possibly via a reduction of mutagenic oxygen-free radicals and by reducing nicotinamide-adeninedinucleotide-phosphate for replicating cells. In Sardinia, the enzyme defect is frequent as a consequence of selection by malaria in the past. This study investigated the relationship between G6PD deficiency and colorectal cancer (CRC).A retrospective case-control study of 3901 patients from Sardinia, who underwent a colonoscopy between 2006 and 2016, was performed. G6PD phenotype was assessed for each subject. The proportion of pre and malignant colorectal lesions was compared in cases (G6PD-deficient) and controls (G6PD-normal). Data concerning age, sex, family history of CRC, smoking habits, body height, and weight, and also associated diseases were collected.The CRC risk reduction was 43.2% among G6PD-deficient compared with G6PD-normal subjects (odds ratio 0.57, 95% confidence interval 0.37-0.87, P = 0.010). Age, sex, family history of CRC, and also comorbidities such as type 1 diabetes and ischemic heart disease, were significantly associated with CRC risk. The protective effect of G6PD deficiency remained significant after adjusting for all covariates by logistic regression analysis, and was consistently lower across all age groups.Glucose-6-phosphate dehydrogenase enzyme deficiency is associated with a reduced risk of CRC.

  9. [Frequency of glucose-6-phosphate dehydrogenase deficiency (A-376/202) in three Malian ethnic groups].

    PubMed

    Dolo, A; Maiga, B; Guindo, A; Diakité, S A S; Diakite, M; Tapily, A; Traoré, M; Sangaré, B; Arama, C; Daou, M; Doumbo, O

    2014-08-01

    Erythrocyte G6PD deficiency is the most common worldwide enzymopathy. The aim of this study was to determine erythrocyte G6PD deficiency in 3 ethnic groups of Mali and to investigate whether erythrocyte G6PD deficiency was associated to the observed protection against malaria seen in Fulani ethnic group. The study was conducted in two different areas of Mali: in the Sahel region of Mopti where Fulani and Dogon live as sympatric ethnic groups and in the Sudanese savannah area where lives mostly the Malinke ethnic group. The study was conducted in 2007 in Koro and in 2008 in Naguilabougou. It included a total 90 Dogon, 42 Fulani and 80 Malinke ethnic groups. Malaria was diagnosed using microscopic examination after Giemsa-staining of thick and thin blood smear. G6PD deficiency (A-(376/202)) samples were identified using RFLP (Restriction Fragment Length Polymorphism) assay and analysis of PCR-amplified DNA amplicon. G6PD deficiency (A-(376/202)) rate was 11.1%, 2.4%, and 13.3% in Dogon, Fulani, and Malinke ethnic group respectively. Heterozygous state for G6PD (A-(376/202)) was found in 7.8% in Dogon; 2.4% in Fulani and 9.3% in Malinke ethnic groups while hemizygous state was found at the frequency of 2.2% in Dogon and 4% in Malinke. No homozygous state was found in our study population.We conclude that G6PD deficiency is not differing significantly between the three ethnic groups, Fulani, Dogon and Malinke.

  10. Effect of feeding and of DDT on the activity of hepatic glucose 6- phosphate dehydrogenase in two salmonids

    USGS Publications Warehouse

    Buhler, Donald R.; Benville, P.

    1969-01-01

    The specific activity of liver glucose 6-phosphate dehydrogenase in yearling rainbow trout remained unchanged when the fish were starved for periods as long as 8 weeks and when starved animals were fed diets of various compositions. Injection of insulin concurrently with refeeding also failed to alter the specific activity of the enzyme in trout. The absence of a dietary or insulin influence on the teleost enzyme system is to be contrasted with studies in mammals in which the activity of hepatic glucose 6-P dehydrogenase was markedly stimulated after refeeding starved animals or injection of insulin.Ingestion of the pesticide DDT by juvenile coho salmon or adult rainbow trout also had no effect on the specific activity of liver glucose 6-P dehydrogenase and DDT failed to inhibit the rainbow trout enzyme in vitro. These results also differ considerably from those found in higher animals.These results suggest that the glucose 6-P dehydrogenase enzyme in teleosts may be under a different type of regulatory control from that found in mammals.

  11. Effects of glucose-6-phosphate dehydrogenase deficiency on the metabolic and cardiac responses to obesogenic or high-fructose diets.

    PubMed

    Hecker, Peter A; Mapanga, Rudo F; Kimar, Charlene P; Ribeiro, Rogerio F; Brown, Bethany H; O'Connell, Kelly A; Cox, James W; Shekar, Kadambari C; Asemu, Girma; Essop, M Faadiel; Stanley, William C

    2012-10-15

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common human enzymopathy that affects cellular redox status and may lower flux into nonoxidative pathways of glucose metabolism. Oxidative stress may worsen systemic glucose tolerance and cardiometabolic syndrome. We hypothesized that G6PD deficiency exacerbates diet-induced systemic metabolic dysfunction by increasing oxidative stress but in myocardium prevents diet-induced oxidative stress and pathology. WT and G6PD-deficient (G6PDX) mice received a standard high-starch diet, a high-fat/high-sucrose diet to induce obesity (DIO), or a high-fructose diet. After 31 wk, DIO increased adipose and body mass compared with the high-starch diet but to a greater extent in G6PDX than WT mice (24 and 20% lower, respectively). Serum free fatty acids were increased by 77% and triglycerides by 90% in G6PDX mice, but not in WT mice, by DIO and high-fructose intake. G6PD deficiency did not affect glucose tolerance or the increased insulin levels seen in WT mice. There was no diet-induced hypertension or cardiac dysfunction in either mouse strain. However, G6PD deficiency increased aconitase activity by 42% and blunted markers of nonoxidative glucose pathway activation in myocardium, including the hexosamine biosynthetic pathway activation and advanced glycation end product formation. These results reveal a complex interplay between diet-induced metabolic effects and G6PD deficiency, where G6PD deficiency decreases weight gain and hyperinsulinemia with DIO, but elevates serum free fatty acids, without affecting glucose tolerance. On the other hand, it modestly suppressed indexes of glucose flux into nonoxidative pathways in myocardium, suggesting potential protective effects.

  12. An audit of the precipitating factors for haemolytic crisis among glucose-6-phosphate dehydrogenase-deficient paediatric patients.

    PubMed

    Al-Azzam, Sayer I; Al-Ajlony, Mohammad J; Al-Khateeb, Taqwa; Alzoubi, Karem H; Mhaidat, Nizar; Ayoub, Abeer

    2009-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common genetic enzyme deficiencies leading to haemolytic anaemia. This study aimed to investigate the precipitating factors for haemolytic crisis in G6PD-deficient paediatric patients in Jordan. A retrospective study of data from the records of 258 paediatric patients admitted to a major paediatric hospital in North Jordan from January 2001 until April 2007. Patients included were G6PD-deficient children who were admitted to the hospital secondary to an episode of haemolytic anaemia. Of 258 paediatric patients, 244 (94.2%) had developed a haemolytic episode secondary to ingestion of fava beans. The remaining 14 children (5.8%) developed a haemolytic episode triggered by other factors, such as drugs and upper respiratory infections. Fava bean ingestion is the major precipitating factor for haemolytic anaemia episodes among G6PD-deficient children in Jordan.

  13. Co-occurrence of biphenotypic acute leukaemia, glucose 6-phosphate dehydrogenase deficiency and haemoglobin E trait in a single child.

    PubMed

    Mallick, Debkrishna; Thapa, Rajoo; Biswas, Biswajit

    2016-02-01

    Acute leukaemias occur as the result of clonal expansion subsequent to transformation and arrest at a normal differentiation stage of haematopoietic precursors, which commit to a single lineage, such as myeloid or B-lymphoid or T-lymphoid cells. Biphenotypic acute leukaemia (BAL) constitutes a biologically different group of leukaemia arising from a precursor stem cell and co-expressing more than one lineage specific marker. The present report describes a child with unusual co-occurrence of biphenotypic (B-precursor cell and Myeloid) acute leukaemia, haemoglobin E trait and glucose 6-phosphate dehydrogenase (G6-PD) deficiency. To the best of our knowledge, this constellation of haematological conditions in a single child has never been described before.

  14. Periodontal considerations in a patient with glucose-6-phosphate dehydrogenase deficiency with associated pancytopenia: A rare case report.

    PubMed

    Gupta, Harinder; Arora, Ruchika; Kamboj, Monika

    2014-03-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzyme defect in humans. G6PD deficiency is widely distributed in tropical and subtropical parts of the world and a conservative estimate is that at least 500 million people have a G6PD deficient gene. In several of these areas, the frequency of a G6PD deficiency gene may be as high as 20% or more. The vast majority of people with G6PD deficiency remain clinically asymptomatic throughout their lifetime. However, all of them have an increased risk of developing neonatal jaundice and a risk of developing acute hemolytic anemia when challenged by a number of oxidative agents. The most important treatment measure is prevention: Avoidance of the drugs and foods that cause hemolysis.

  15. X-linked glucose-6-phosphate dehydrogenase (G6PD) and autosomal 6-phosphogluconate dehydrogenase (6PGD) polymorphisms in baboons

    SciTech Connect

    VandeBerg, J.L.; Aivaliotis, M.J.; Samollow, P.B. )

    1992-12-01

    Electrophoretic polymorphisms of glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) were examined in captive colonies of five subspecies of baboons (Papio hamadryas). Phenotype frequencies and family data verified the X-linked inheritance of the G6PD polymorphism. Insufficient family data were available to confirm autosomal inheritance of the 6PGD polymorphism, but the electrophoretic patterns of variant types (putative heterozygotes) suggested the codominant expression of alleles at an autosomal locus. Implications of the G6PD polymorphism are discussed with regard to its utility as a marker system for research on X-chromosome inactivation during baboon development and for studies of clonal cell proliferation and/or cell selection during the development of atherosclerotic lesions in the baboon model. 61 refs., 1 fig., 4 tabs.

  16. Inhibition of catalase by aminotriazole in vivo results in reduction of glucose-6-phosphate dehydrogenase activity in Saccharomyces cerevisiae cells.

    PubMed

    Bayliak, M; Gospodaryov, D; Semchyshyn, H; Lushchak, V

    2008-04-01

    The inhibitor of catalase 3-amino-1,2,4-triazole (AMT) was used to study the physiological role of catalase in the yeast Saccharomyces cerevisiae under starvation. It was shown that AMT at the concentration of 10 mM did not affect the growth of the yeast. In vivo and in vitro the degree of catalase inhibition by AMT was concentration- and time-dependent. Peroxisomal catalase in bakers' yeast was more sensitive to AMT than the cytosolic one. In vivo inhibition of catalase by AMT in S. cerevisiae caused a simultaneous decrease in glucose-6-phosphate dehydrogenase activity and an increase in glutathione reductase activity. At the same time, the level of protein carbonyls, a marker of oxidative modification, was not affected. Possible mechanisms compensating the negative effects caused by AMT inhibition of catalase are discussed.

  17. Glucose 6-phosphate dehydrogenase variants: a unique variant (G6PD Kobe) showed an extremely increased affinity for galactose 6-phosphate and a new variant (G6PD Sapporo) resembling G6PD Pea Ridge.

    PubMed

    Fujii, H; Miwa, S; Tani, K; Takegawa, S; Fujinami, N; Takahashi, K; Nakayama, S; Konno, M; Sato, T

    1981-01-01

    Two new glucose 6-phosphate dehydrogenase (G6PD) variants associated with chronic nonspherocytic hemolytic anemia were discovered, G6PD Kobe was found in a 16-year-old male associated with hemolytic crisis after upper respiratory infection. The enzyme activity of the variant was about 22% of that of the normal enzyme. The main enzymatic characteristics were slower than normal anodal electrophoretic mobility, high Km G6P, increased thermal-instability, an acidic pH optimum, and an extremely increased affinity for the substrate analogue, galactose 6-phosphate (Gal-6P). G6PD Sapporo was found in a 3-year-old male associated with drug-induced hemolysis. The enzyme activity was extremely low, being 3.6% of normal. In addition, this variant showed high Ki NADPH and thermal-instability. G6PD Kobe utilized the artificial substrate Gal-6P effectively as compared with the common natural substrate, glucose 6-phosphate. In G6PD Sapporo, NADPH could not exert the effect of product inhibition. The structural changes of these variants are expected to occur at the portions inducing conformational changes of the substrate binding site of the enzyme.

  18. The glucose-6-phosphate dehydrogenase from Trypanosoma cruzi: its role in the defense of the parasite against oxidative stress.

    PubMed

    Igoillo-Esteve, Mariana; Cazzulo, Juan José

    2006-10-01

    The Trypanosoma cruzi glucose-6-phosphate dehydrogenase (G6PDH) is encoded by several genes located in three of the parasite chromosomes. All the sequences present two possible start codons, 111bp apart, also present in its Trypanosoma brucei counterpart. As the 37 residues comprised between the two candidate initiator methionines of T. brucei and T. cruzi G6PDHs constitute an unusual N-terminal extension only present in trypanosomatids, two forms of the T. cruzi G6PDH were expressed in Escherichia coli: a long one (Tc-G6PDH-L) translated from the first ATG codon, and a short one (Tc-G6PDH-S) translated from the second. Both were purified and their kinetic constants determined. The apparent K(m) for glucose-6-phosphate was 189.9, 98.4, and 288microM, for Tc-G6PDH-L, Tc-G6PDH-S and native Tc-G6PDH, respectively. The apparent K(m) for NADP was similar for both recombinant proteins. The Tc-G6PDH-L as well as the native enzyme, was inactivated by DTT while the Tc-G6PDH-S was unaffected by the reducing agent. This behavior could be related to the presence of two Cys groups in the N-terminal extension of the Tc-G6PDH-L similarly to the redox regulated G6PDHs from chloroplasts and cyanobacteria. This property, together with a remarkable induction (up to 46-fold) of the T. cruzi G6PDH in metacyclic trypomastigotes under oxidative stress conditions, suggests that the enzyme may play a prominent role in the defense mechanisms of the parasite against oxidative stress becoming an important target for chemotherapy. Western blots using antibodies against the N-terminal extension in Tc-G6PDH-L show that this form is expressed in the parasite.

  19. Fluoride-containing bioactive glasses inhibit pentose phosphate oxidative pathway and glucose 6-phosphate dehydrogenase activity in human osteoblasts.

    PubMed

    Bergandi, Loredana; Aina, Valentina; Garetto, Stefano; Malavasi, Gianluca; Aldieri, Elisabetta; Laurenti, Enzo; Matera, Lina; Morterra, Claudio; Ghigo, Dario

    2010-02-12

    Bioactive glasses such as Hench's 45S5 (Bioglass) have applications to tissue engineering as well as bone repair, and the insertion of fluoride in their composition has been proposed to enhance their bioactivity. In view of a potential clinical application, we investigated whether fluoride-containing glasses exert toxic effects on human MG-63 osteoblasts, and whether and how fluoride, which is released in the cell culture medium, might play a role in such cytotoxicity. A 24h incubation with 50 microg/ml (12.5 microg/cm(2)) of fluoride-containing bioactive glasses termed HCaCaF(2) (F content: 5, 10 and 15 mol.%) caused the release of lactate dehydrogenase in the extracellular medium (index of cytotoxicity), the accumulation of intracellular malonyldialdehyde (index of lipoperoxidation), and the increase of glutathione consumption. Furthermore, fluoride-containing glasses inhibited the pentose phosphate oxidative pathway and the glucose 6-phosphate dehydrogenase activity. These effects are ascribable to the fluoride content/release of glass powders, since they were mimicked by NaF solutions and were prevented by dimethyl sulfoxide and tempol (two radical scavengers), by superoxide dismutase (a superoxide scavenger), and by glutathione (the most important intracellular antioxidant molecule), but not by apocynin (an inhibitor of NADPH oxidase). The presence of fluoride-containing glasses and NaF caused also the generation of reactive oxygen species, which was prevented by superoxide dismutase and catalase. The data suggest that fluoride released from glasses is the cause of MG-63 cell oxidative damage and is independent of NADPH oxidase activation. Our data provide a new mechanism to explain F(-) ions toxicity: fluoride could trigger, at least in part, an oxidative stress via inhibition of the pentose phosphate oxidative pathway and, in particular, through the oxidative inhibition of glucose 6-phosphate dehydrogenase.

  20. Free fatty acid inhibition of the insulin induction of glucose-6-phosphate dehydrogenase in rat hepatocyte monolayers.

    PubMed

    Salati, L M; Adkins-Finke, B; Clarke, S D

    1988-01-01

    Rat hepatocytes in monolayer culture were utilized to determine if the decrease in glucose-6-phosphate dehydrogenase (G6PD) activity resulting from the ingestion of fat can be mimicked by the addition of fatty acids to a chemically, hormonally defined medium. G6PD activity in cultured hepatocytes was induced several-fold by insulin. Dexamethasone or T3 did not amplify the insulin induction of G6PD. Glucose alone increased G6PD activity in cultured hepatocytes from fasted donors by nearly 500%. Insulin in combination with glucose induced G6PD an additional two-fold. The increase in G6PD activity caused by glucose was greater in hepatocytes isolated from 72 hr-fasted rats as compared to fed donor rats. Such a response was reminiscent of the "overshoot" phenomenon in which G6PD activity is induced well above the normal level by fasting-refeeding rats a high glucose diet. Addition of linoleate to the medium resulted in a significant suppression of insulin's ability to induce G6PD, but linoleate had no effect on the induction of G6PD activity by glucose alone. A shift to the right in the insulin-response curve for the induction of G6PD also was detected for the induction of malic enzyme and acetyl-CoA carboxylase. Arachidonate (0.25 mM) was a significantly more effective inhibitor of the insulin action than linoleate was. Apparently rat hepatocytes in monolayer culture can be utilized as a model to investigate the molecular mechanism by which fatty acids inhibit the production of lipogenic enzymes. In part, this mechanism of fatty acid inhibition involves desensitization of hepatocytes to the lipogenic action of insulin.

  1. Time course of radiolabeled 2-deoxy-D-glucose 6-phosphate turnover in cerebral cortex of goats

    SciTech Connect

    Pelligrino, D.A.; Miletich, D.J.; Albrecht, R.F.

    1987-02-01

    The vivo dephosphorylation rate of 2-deoxy-D-glucose 6-phosphate (DGP) in the cerebral cortex of goats injected intravenously with radiolabeled 2-deoxy-D-glucose (DG) was investigated. Serial rapidly frozen samples of parietal cortical gray tissue were obtained at regular intervals over time periods from 45 min to 3 h in awake goats or in paralyzed and artificially ventilated goats maintained under 70% N/sub 2/O or pentobarbital sodium anesthesia. The samples were analyzed for glucose content and separate DG and DGP activities. The rate parameters for phosphorylation (k/sup *//sub 4/) and dephosphorylation (k/sup *//sub 4/) were estimated in each animal. The glucose phosphorylation rate (PR) was calculated over the intervals 3-5 (or 6), 3-10, 3-20, 3-30, and 3-45 min, assuming k/sup *//sub 4/ = O. As the evaluation period was extended beyond 10 min, the calculated PR became increasingly less when compared with that calculated over the 3- to 5- (or 6) min interval (PR/sub i/). Furthermore, as metabolic activity decreased, the magnitude of the error increased such that at 45 min pentobarbital-anesthetize goats underestimated the PR/sub i/ by 46.5% compared with only 23.1 in N/sub 2/O-anesthetized goats. This was also reflected in the >twofold higher k/sup *//sub 4//k/sup *//sub 3/ ratio in the pentobarbital vs. N/sub 2/O-anesthetized group. It is concluded that when using the DG method in the goat, DGP dephosphorylation cannot be ignored when employing >10-min evaluation periods.

  2. 2-Deoxy-2-fluoro-D-glucose as a functional probe for NMR: the unique metabolism beyond its 6-phosphate.

    PubMed

    Kanazawa, Y; Yamane, H; Shinohara, S; Kuribayashi, S; Momozono, Y; Yamato, Y; Kojima, M; Masuda, K

    1996-05-01

    Epimeric conversion of 2-deoxy-2-fluoro-D-glucose (FDG) to its 2-epimer 2-deoxy-2-fluoro-D-mannose (FDM) proved by 19F NMR has been shown to reflect the brain activity. To examine the feasibility of FDG as a new NMR probe for in vivo functional monitoring, we studied here the fundamental NMR properties of metabolites, spectral assignments, and reliability of NMR quantification. Metabolites confirmed in brain besides FDM-6-phosphate were as follows: FDG-1-phosphate, FDG-1,6-bisphosphate, FDM-1-phosphate, FDM-1,6-bisphosphate, and FDG and FDM derivatives of nucleotide diphosphate. NMR quantification of these metabolites was evaluated in comparison with the method of 18F-labeled FDG. In the NMR functional study using FDG, where a high dose is inevitable, the dose dependence of uptake was investigated. FDG uptake in mouse brain was shown to be in the range of interpretation using the biochemical parameters of enzymes for glucose uptake as long as a dose of < 200 mg/kg was used.

  3. Glucose-6-Phosphate-Dehydrogenase Is Also Increased in Erythrocytes from Adolescents with Down Syndrome

    ERIC Educational Resources Information Center

    Ordonez, Francisco J.; Rosety-Plaza, Manuel; Rosety-Rodriguez, Manuel

    2006-01-01

    For some time it has been claimed that trisomic cells are more sensitive to oxidative stress since there is an imbalance in hydrogen peroxide metabolism due to an increase in superoxide dismutase (SOD) catalytic activity. We designed the present study to assess activity levels of antioxidant enzymes [superoxide dismutase (SOD), glutathione…

  4. Glucose-6-Phosphate-Dehydrogenase Is Also Increased in Erythrocytes from Adolescents with Down Syndrome

    ERIC Educational Resources Information Center

    Ordonez, Francisco J.; Rosety-Plaza, Manuel; Rosety-Rodriguez, Manuel

    2006-01-01

    For some time it has been claimed that trisomic cells are more sensitive to oxidative stress since there is an imbalance in hydrogen peroxide metabolism due to an increase in superoxide dismutase (SOD) catalytic activity. We designed the present study to assess activity levels of antioxidant enzymes [superoxide dismutase (SOD), glutathione…

  5. An unexpected emergency request for glucose-6-phosphate dehydrogenase testing in a 9-year-old African American boy.

    PubMed

    Platteborze, Peter; Matos, Renee; Gidvany-Diaz, Vinod; Wilhelms, Kelly

    2015-01-01

    9-year-old African American male. Recently diagnosed with acute lymphoblastic leukemia (ALL) after investigation into a large anterior mediastinal mass causing airway compression. The day before the unexpected urgent glucose-6-phosphate dehydrogenase (G6PD) request, the patient was diagnosed with an aggressive form of leukemia and a significant tumor mass causing airway compression. A computed tomography (CT) scan indicated potential renal involvement. Based on this information and the size of the mass, the patient was referred for immediate chemotherapy. However, there was a concern that he could develop tumor lysis syndrome (TLS) during treatment. To avoid this condition, the pediatric intensive care unit (ICU) sought to pretreat the child with rasburicase, which led to the emergency G6PD request. Unknown. Largely unknown, but no apparent chronic diseases. Three weeks of progressively worsening lymphadenopathy, coughing, night sweats, mild hepatosplenomegaly, and breathing difficulty when supine. The patient arrived at the medical center for airway management and had a temperature of 36.1°C; blood pressure, 120/87 mmHg; pulse, 115 bpm; respiratory rate, 22 breaths per minute, with labored breathing but normal O(2) saturation while upright and awake, in room air. Table 1. Copyright© by the American Society for Clinical Pathology (ASCP).

  6. Determination of the inhibitory effect of green tea extract on glucose-6-phosphate dehydrogenase based on multilayer capillary enzyme microreactor.

    PubMed

    Camara, Mohamed Amara; Tian, Miaomiao; Liu, Xiaoxia; Liu, Xin; Wang, Yujia; Yang, Jiqing; Yang, Li

    2016-08-01

    Natural herbal medicines are an important source of enzyme inhibitors for the discovery of new drugs. A number of natural extracts such as green tea have been used in prevention and treatment of diseases due to their low-cost, low toxicity and good performance. The present study reports an online assay of the activity and inhibition of the green tea extract of the Glucose 6-phosphate dehydrogenase (G6PDH) enzyme using multilayer capillary electrophoresis based immobilized enzyme microreactors (CE-IMERs). The multilayer CE-IMERs were produced with layer-by-layer electrostatic assembly, which can easily enhance the enzyme loading capacity of the microreactor. The activity of the G6PDH enzyme was determined and the enzyme inhibition by the inhibitors from green tea extract was investigated using online assay of the multilayer CE-IMERs. The Michaelis constant (Km ) of the enzyme, the IC50 and Ki values of the inhibitors were achieved and found to agree with those obtained using offline assays. The results show a competitive inhibition of green tea extract on the G6PDH enzyme. The present study provides an efficient and easy-to-operate approach for determining G6PDH enzyme reaction and the inhibition of green tea extract, which may be beneficial in research and the development of natural herbal medicines. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Application of capillary enzyme micro-reactor in enzyme activity and inhibitors studies of glucose-6-phosphate dehydrogenase.

    PubMed

    Camara, Mohamed Amara; Tian, Miaomiao; Guo, Liping; Yang, Li

    2015-05-15

    In this study, we present an on-line measurement of enzyme activity and inhibition of Glucose-6-phosphate dehydrogenase (G6PDH) enzyme using capillary electrophoresis based immobilized enzyme micro-reactor (CE-based IMER). The IMER was prepared using a two-step protocol based on electrostatic assembly. The micro-reactor exhibited good stability and reproducibility for on-line assay of G6PDH enzyme. Both the activity as well as the inhibition of the G6PDH enzyme by six inhibitors, including three metals (Cu(2+), Pb(2+), Cd(2+)), vancomycin, urea and KMnO4, were investigated using on-line assay of the CE-based IMERs. The enzyme activity and inhibition kinetic constants were measured using the IMERs which were found to be consistent with those using traditional off-line enzyme assays. The kinetic mechanism of each inhibitor was also determined. The present study demonstrates the feasibility of using CE-based IMERs for rapid and efficient on-line assay of G6PDH, an important enzyme in the pentosephosphate pathway of human metabolism.

  8. Hemoglobin E and Glucose-6-Phosphate Dehydrogenase Deficiency and Plasmodium falciparum Malaria in the Chittagong Hill Districts of Bangladesh

    PubMed Central

    Shannon, Kerry L.; Ahmed, Sabeena; Rahman, Hafizur; Prue, Chai S.; Khyang, Jacob; Ram, Malathi; Zahirul Haq, M.; Chowdhury, Ashish; Akter, Jasmin; Glass, Gregory E.; Shields, Timothy; Nyunt, Myaing M.; Khan, Wasif A.; Sack, David A.; Sullivan, David J.

    2015-01-01

    Hemoglobin E is largely confined to south and southeast Asia. The association between hemoglobin E (HbE) and malaria is less clear than that of hemoglobin S and C. As part of a malaria study in the Chittagong Hill Districts of Bangladesh, an initial random sample of 202 individuals showed that 39% and 49% of Marma and Khyang ethnic groups, respectively, were positive for either heterozygous or homozygous hemoglobin E. In this group, 6.4% were also found to be severely deficient and 35% mildly deficient for glucose-6-phosphate dehydrogenase (G6PD). In a separate Plasmodium falciparum malaria case–uninfected control study, the odds of having homozygous hemoglobin E (HbEE) compared with normal hemoglobin (HbAA) were higher among malaria cases detected by passive surveillance than age and location matched uninfected controls (odds ratio [OR] = 5.0, 95% confidence interval [CI] = 1.07–46.93). The odds of heterozygous hemoglobin E (HbAE) compared with HbAA were similar between malaria cases and uninfected controls (OR = 0.71, 95% CI = 0.42–1.19). No association by hemoglobin type was found in the initial parasite density or the proportion parasite negative after 2 days of artemether/lumefantrine treatment. HbEE, but not HbAE status was associated with increased passive case detection of malaria. PMID:26101273

  9. Incidence and molecular characterization of Glucose-6-Phosphate Dehydrogenase deficiency among neonates for newborn screening in Chaozhou, China.

    PubMed

    Yang, H; Wang, Q; Zheng, L; Zhan, X-F; Lin, M; Lin, F; Tong, X; Luo, Z-Y; Huang, Y; Yang, L-Y

    2015-06-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is highly prevalent in southern China. The aim of this study is to assess the extent of this disease in Chinese neonates and determine its molecular characteristics using a novel molecular screening method. A total of 2500 neonates were routinely screened for G6PD deficiency using a modified fluorescent spot test (FST). PCR-high-resolution melting (HRM) analysis was then used for the molecular assay. The overall incidence of G6PD deficiency was 2.68% in our study cohort. Frequency in male population was 3.22% (44 neonates of 1365 male neonates), and in female population was 2.03% (23 neonates of 1135 female neonates). Of the 67 newborns suspected to be G6PD deficient based on FST (44 males, 23 females), 58 of 67 (87%) were detected with gene alterations. Seven kinds of mutations [c.95A>G, c.392G>T, c.493A>G, c.871G>A, c.1360C>T, c.1376G>T, and c.1388G>A] were identified by HRM analysis. Routine newborn screening in Chaozhou, China with a relatively high prevalence of G6PD deficiency is justified and meets the World Health Organization recommendation. The usage of molecular diagnosis can favor the detection of heterozygotes which can be a supplement to regular newborn screening and useful for premarital and prenatal diagnosis for G6PD deficiency. © 2014 John Wiley & Sons Ltd.

  10. AB222. Enolase1 (ENO1) and glucose-6-phosphate isomerase (GPI) are good markers to predict human sperm freezability

    PubMed Central

    Jiang, Xuping; Wang, Shangqian; Wang, Wei; Xu, Yang; Sun, Hongyong; Wang, Zengjun; Zhang, Wei

    2016-01-01

    Objective Sperm cryopreservation is a method to preserve sperm samples for a long period. However, the fertility of sperm decreases markedly after freezing and thawing in a certain amount of samples. The aim of the present study was to find useful and reliable predictive biomarkers of the capacity to withstand the freeze-thawing process in human ejaculates. Methods We chose the two proteins as probable markers of sperm freezing capacity. Ejaculate samples were separated into good freezability ejaculates (GFE) and poor freezability ejaculates (PFE) according to progressive motility of the sperm after thawing. Before starting cryopreservation protocols, the two proteins from each group were compared using western blot analysis and immunofluorescence. Results Results showed that normalized content of enolase1 (ENO1) (P<0.05) and glucose-6-phosphate isomerase (GPI) (P<0.01) were both significantly higher in GFE than in PFE. The association of ENO1 and GPI with post thaw sperm viability and motility was confirmed using Pearson’s linear correlation. Conclusions In conclusion, ENO1 and GPI can be used as markers of human sperm freezability before starting the cryopreservation procedure.

  11. Cloning, characterization and computational analysis of the 5' regulatory region of ovine glucose 6-phosphate dehydrogenase gene.

    PubMed

    Laliotis, George P; Bizelis, Iosif; Argyrokastritis, Alexandros; Rogdakis, Emmanuel

    2007-08-01

    To better understand the structure and the function of ovine glucose 6-phosphate dehydrogenase (G6PD) promoter region, a genome-walking procedure was followed to isolate and sequence a 1628 bp fragment, containing the 5' regulatory region of the G6PD gene. In silico analysis of the sequence showed many conserved blocks and features with other known mammalian G6PD promoter regions. The analysis also revealed the presence of one TATA box, three GC boxes, two E-boxes and several binding sites for Stimulating Protein 1 (Sp1) and Activator Protein 2 (AP2). Moreover, elements involved in the regulation of lipogenesis like USF (Upstream stimulating factor), HSF (Heat Shock Factor), F2F (Prolactin receptor), RAR (Retinoid Acid Receptor), STRE (STress Response Element), RORa (Retinoid related Orphan Receptor alpha), GATA (GATA binding factor), RFX (Regulatory Factor X), SREBP (Sterol Regulatory Element Binding Protein), MEP (Metal Element Protein), CREB (insulin receptor), PRE (Progesterone receptor), and HNF4 (Hepatic Nuclear Factor 4) were detected. The most important regulatory motifs were found to be conserved as compared to those in human and mouse counterparts. However, some differences were noted, likely indicating differences in the transcription regulation of G6PD gene between ruminant and non-ruminant species.

  12. Regulation of Enzyme Activities in Drosophila: Genetic Variation Affecting Induction of Glucose 6-Phosphate and 6-Phosphogluconate Dehydrogenases in Larvae

    PubMed Central

    Cochrane, Bruce J.; Lucchesi, John C.; Laurie-Ahlberg, C. C.

    1983-01-01

    The genetic basis of modulation by dietary sucrose of the enzyme activities glucose 6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) activities in third instar larvae of Drosophila melanogaster was investigated, using isogenic lines derived from wild populations. Considerable genetically determined variation in response was detected among lines that differed only in their third chromosome constitution. Comparison of crossreacting material between a responding and a nonresponding line showed that the G6PD activity variation is due to changes in G6PD protein level. These differences in responses are localized in the fat body, with 300 m m sucrose in the diet resulting in a sixfold stimulation of G6PD activity and a fourfold one of 6PGD in the line showing the strongest response. In this tissue, the responses of the two enzymes are closely correlated with one another. Using recombinant lines, we obtained data that suggested the existence of more than one gene on chromosome III involved in the regulation of G6PD in the fat body, and at least one of these genes affects the level of 6PGD as well. PMID:6416921

  13. Molecular cloning and nucleotide sequence of cDNA for human glucose-6-phosphate dehydrogenase variant A(-)

    SciTech Connect

    Hirono, A.; Beutler, E. )

    1988-06-01

    Glucose-6-phosphate dehydrogenase A(-) is a common variant in Blacks that causes sensitivity to drug- and infection-induced hemolytic anemia. A cDNA library was constructed from Epstein-Barr virus-transformed lymphoblastoid cells from a male who was G6PD A(-). One of four cDNA clones isolated contained a sequence not found in the other clones nor in the published cDNA sequence. Consisting of 138 bases and coding 46 amino acids, this segment of cDNA apparently is derived from the alternative splicing involving the 3{prime} end of intron 7. Comparison of the remaining sequences of these clones with the published sequence revealed three nucleotide substitutions: C{sup 33} {yields} G, G{sup 202} {yields} A, and A{sup 376} {yields} G. Each change produces a new restriction site. Genomic DNA from five G6PD A(-) individuals was amplified by the polymerase chain reaction. The findings of the same mutation in G6PD A(-) as is found in G6PD A(+) strongly suggests that the G6PD A(-) mutation arose in an individual with G6PD A(+), adding another mutation that causes the in vivo instability of this enzyme protein.

  14. On-plate enzyme and inhibition assay of glucose-6-phosphate dehydrogenase using thin-layer chromatography.

    PubMed

    Tian, Miaomiao; Mohamed, Amara Camara; Wang, Shengtian; Yang, Li

    2015-08-01

    We performed on-plate enzyme and inhibition assays of glucose 6-phosphate dehydrogenase using thin-layer chromatography. The assays were accomplished based on different retardation factors of the substrates, enzyme, and products. All the necessary steps were integrated on-plate in one developing process, including substrate/enzyme mixing, reaction starting, and quenching as well as product separation. In order to quantitatively measure the enzyme reaction, the developed plate was then densitometrically evaluated to determine the peak area of the product. Rapid and high-throughput assays were achieved by loading different substrate spots and/or enzyme (and inhibition) spots in different tracks on the plate. The on-plate enzyme assay could be finished in a developing time of only 4 min, with good track-to-track and plate-to-plate repeatability. Moreover, we determined the Km values of the enzyme reaction and Ki values of the inhibition (Pb(2+) Cd(2+) and Cu(2+) as inhibitors), as well as the corresponding kinetics using the on-plate assay. Taken together, our method expanded the application of thin-layer chromatography in enzyme assays, and it could be potentially used in research fields for rapid and quantitative measurement of enzyme activity and inhibition. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Functional and Biochemical Characterization of Three Recombinant Human Glucose-6-Phosphate Dehydrogenase Mutants: Zacatecas, Vanua-Lava and Viangchan

    PubMed Central

    Gómez-Manzo, Saúl; Marcial-Quino, Jaime; Vanoye-Carlo, America; Serrano-Posada, Hugo; González-Valdez, Abigail; Martínez-Rosas, Víctor; Hernández-Ochoa, Beatriz; Sierra-Palacios, Edgar; Castillo-Rodríguez, Rosa Angélica; Cuevas-Cruz, Miguel; Rodríguez-Bustamante, Eduardo; Arreguin-Espinosa, Roberto

    2016-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency in humans causes severe disease, varying from mostly asymptomatic individuals to patients showing neonatal jaundice, acute hemolysis episodes or chronic nonspherocytic hemolytic anemia. In order to understand the effect of the mutations in G6PD gene function and its relation with G6PD deficiency severity, we report the construction, cloning and expression as well as the detailed kinetic and stability characterization of three purified clinical variants of G6PD that present in the Mexican population: G6PD Zacatecas (Class I), Vanua-Lava (Class II) and Viangchan (Class II). For all the G6PD mutants, we obtained low purification yield and altered kinetic parameters compared with Wild Type (WT). Our results show that the mutations, regardless of the distance from the active site where they are located, affect the catalytic properties and structural parameters and that these changes could be associated with the clinical presentation of the deficiency. Specifically, the structural characterization of the G6PD Zacatecas mutant suggests that the R257L mutation have a strong effect on the global stability of G6PD favoring an unstable active site. Using computational analysis, we offer a molecular explanation of the effects of these mutations on the active site. PMID:27213370

  16. Functional and Biochemical Characterization of Three Recombinant Human Glucose-6-Phosphate Dehydrogenase Mutants: Zacatecas, Vanua-Lava and Viangchan.

    PubMed

    Gómez-Manzo, Saúl; Marcial-Quino, Jaime; Vanoye-Carlo, America; Serrano-Posada, Hugo; González-Valdez, Abigail; Martínez-Rosas, Víctor; Hernández-Ochoa, Beatriz; Sierra-Palacios, Edgar; Castillo-Rodríguez, Rosa Angélica; Cuevas-Cruz, Miguel; Rodríguez-Bustamante, Eduardo; Arreguin-Espinosa, Roberto

    2016-05-21

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency in humans causes severe disease, varying from mostly asymptomatic individuals to patients showing neonatal jaundice, acute hemolysis episodes or chronic nonspherocytic hemolytic anemia. In order to understand the effect of the mutations in G6PD gene function and its relation with G6PD deficiency severity, we report the construction, cloning and expression as well as the detailed kinetic and stability characterization of three purified clinical variants of G6PD that present in the Mexican population: G6PD Zacatecas (Class I), Vanua-Lava (Class II) and Viangchan (Class II). For all the G6PD mutants, we obtained low purification yield and altered kinetic parameters compared with Wild Type (WT). Our results show that the mutations, regardless of the distance from the active site where they are located, affect the catalytic properties and structural parameters and that these changes could be associated with the clinical presentation of the deficiency. Specifically, the structural characterization of the G6PD Zacatecas mutant suggests that the R257L mutation have a strong effect on the global stability of G6PD favoring an unstable active site. Using computational analysis, we offer a molecular explanation of the effects of these mutations on the active site.

  17. Inhibition of Glucose-6-Phosphate Dehydrogenase Could Enhance 1,4-Benzoquinone-Induced Oxidative Damage in K562 Cells

    PubMed Central

    Cao, Meng; Yang, Wenwen; Sun, Fengmei; Xu, Cheng

    2016-01-01

    Benzene is a chemical contaminant widespread in industrial and living environments. The oxidative metabolites of benzene induce toxicity involving oxidative damage. Protecting cells and cell membranes from oxidative damage, glucose-6-phosphate dehydrogenase (G6PD) maintains the reduced state of glutathione (GSH). This study aims to investigate whether the downregulation of G6PD in K562 cell line can influence the oxidative toxicity induced by 1,4-benzoquinone (BQ). G6PD was inhibited in K562 cell line transfected with the specific siRNA of G6PD gene. An empty vector was transfected in the control group. Results revealed that G6PD was significantly upregulated in the control cells and in the cells with inhibited G6PD after they were exposed to BQ. The NADPH/NADP and GSH/GSSG ratio were significantly lower in the cells with inhibited G6PD than in the control cells at the same BQ concentration. The relative reactive oxygen species (ROS) level and DNA oxidative damage were significantly increased in the cell line with inhibited G6PD. The apoptotic rate and G2 phase arrest were also significantly higher in the cells with inhibited G6PD and exposed to BQ than in the control cells. Our results suggested that G6PD inhibition could reduce GSH activity and alleviate oxidative damage. G6PD deficiency is also a possible susceptible risk factor of benzene exposure. PMID:27656260

  18. Hemoglobin E and Glucose-6-Phosphate Dehydrogenase Deficiency and Plasmodium falciparum Malaria in the Chittagong Hill Districts of Bangladesh.

    PubMed

    Shannon, Kerry L; Ahmed, Sabeena; Rahman, Hafizur; Prue, Chai S; Khyang, Jacob; Ram, Malathi; Haq, M Zahirul; Chowdhury, Ashish; Akter, Jasmin; Glass, Gregory E; Shields, Timothy; Nyunt, Myaing M; Khan, Wasif A; Sack, David A; Sullivan, David J

    2015-08-01

    Hemoglobin E is largely confined to south and southeast Asia. The association between hemoglobin E (HbE) and malaria is less clear than that of hemoglobin S and C. As part of a malaria study in the Chittagong Hill Districts of Bangladesh, an initial random sample of 202 individuals showed that 39% and 49% of Marma and Khyang ethnic groups, respectively, were positive for either heterozygous or homozygous hemoglobin E. In this group, 6.4% were also found to be severely deficient and 35% mildly deficient for glucose-6-phosphate dehydrogenase (G6PD). In a separate Plasmodium falciparum malaria case-uninfected control study, the odds of having homozygous hemoglobin E (HbEE) compared with normal hemoglobin (HbAA) were higher among malaria cases detected by passive surveillance than age and location matched uninfected controls (odds ratio [OR] = 5.0, 95% confidence interval [CI] = 1.07-46.93). The odds of heterozygous hemoglobin E (HbAE) compared with HbAA were similar between malaria cases and uninfected controls (OR = 0.71, 95% CI = 0.42-1.19). No association by hemoglobin type was found in the initial parasite density or the proportion parasite negative after 2 days of artemether/lumefantrine treatment. HbEE, but not HbAE status was associated with increased passive case detection of malaria.

  19. False-Positive Newborn Screen Using the Beutler Spot Assay for Galactosemia in Glucose-6-Phosphate Dehydrogenase Deficiency.

    PubMed

    Stuhrman, Grace; Perez Juanazo, Stefanie J; Crivelly, Kea; Smith, Jennifer; Andersson, Hans; Morava, Eva

    2017-01-12

    Classical galactosemia is detected through newborn screening by measuring galactose-1-phosphate uridylyltransferase (GALT) in the USA primarily via the Beutler spot assay. We report on an 18-month-old patient with glucose-6-phosphate dehydrogenase (G6PD) deficiency that was originally diagnosed with classical galactosemia. The patient presented with elevated liver function enzymes and bilirubinemia and was immediately treated with soy-based formula. Confirmatory tests revealed deficiency of the GALT enzyme, however, full-sequencing of GALT was normal, suggestive of a different ideology. The Beutler spot assay uses three other enzymatic steps in addition to GALT. A deficiency in either of these enzymes can result in suspected decreased GALT activity when using the Beutler assay. Congenital Disorders of Glycosylation screening for phosphoglucomutase-1 deficiency was negative. Quantitative analysis of G6PD enzyme in red blood cells showed a severe deficiency and a deletion in G6PD. Soy-formula, the standard treatment for galactosemia, has been reported to trigger hemolysis in G6PD deficient patients. G6PD and phosphoglucomutase-1 deficiencies should be considered when confirmatory tests are negative for pathogenic variants in GALT and galactose-1-phosphate level is normal.

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

    PubMed

    Al-Abdi, Sameer Yaseen

    2017-02-01

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

  1. Glucose-6-phosphate isomerase is an endogenous inhibitor to myofibril-bound serine proteinase of crucian carp (Carassius auratus).

    PubMed

    Sun, Le-Chang; Zhou, Li-Gen; Du, Cui-Hong; Cai, Qiu-Feng; Hara, Kenji; Su, Wen-Jin; Cao, Min-Jie

    2009-06-24

    Glucose-6-phosphate isomerase (GPI) was purified to homogeneity from the skeletal muscle of crucian carp ( Carassius auratus ) by ammonium sulfate fractionation, column chromatographies of Q-Sepharose, SP-Sepharose, and Superdex 200 with a yield of 8.0%, and purification folds of 468. The molecular mass of GPI was 120 kDa as estimated by gel filtration, while on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), two subunits (55 and 65 kDa) were identified, suggesting that it is a heterodimer. Interestingly, GPI revealed specific inhibitory activity toward a myofibril-bound serine proteinase (MBSP) from crucian carp, while no inhibitory activity was identified toward other serine proteinases, such as white croaker MBSP and crucian carp trypsin. Kinetic analysis showed that GPI is a competitive inhibitor toward MBSP, and the K(i) was 0.32 microM. Our present results indicated that the multifunctional protein GPI is an endogenous inhibitor to MBSP and may play a significant role in the regulation of muscular protein metabolism in vivo.

  2. Clonal evolution following chemotherapy-induced stem cell depletion in cats heterozygous for glucose-6-phosphate dehydrogenase

    SciTech Connect

    Abkowitz, J.L.; Ott, R.M.; Holly, R.D.; Adamson, J.W.

    1988-06-01

    The number of hematopoietic stem cells necessary to support normal hematopoiesis is not known but may be small. If so, the depletion or damage of such cells could result in apparent clonal dominance. To test this hypothesis, dimethylbusulfan (2 to 4 mg/kg intravenously (IV) x 3) was given to cats heterozygous for the X-linked enzyme glucose-6-phosphate dehydrogenase (G-6-PD). These cats were the daughters of domestic X Geoffroy parents. After the initial drug-induced cytopenias (2 to 4 weeks), peripheral blood counts and the numbers of marrow progenitors detected in culture remained normal, although the percentages of erythroid burst-forming cells (BFU-E) and granulocyte/macrophage colony-forming cells (CFU-GM) in DNA synthesis increased, as determined by the tritiated thymidine suicide technique. In three of six cats treated, a dominance of Geoffroy-type G-6-PD emerged among the progenitor cells, granulocytes, and RBCs. These skewed ratios of domestic to Geoffroy-type G-6-PD have persisted greater than 3 years. No changes in cell cycle kinetics or G-6-PD phenotypes were noted in similar studies in six control cats. These data suggest that clonal evolution may reflect the depletion or damage of normal stem cells and not only the preferential growth and dominance of neoplastic cells.

  3. Role of glucose-6-phosphate dehydrogenase inhibition in the antiproliferative effects of dehydroepiandrosterone on human breast cancer cells.

    PubMed Central

    Di Monaco, M.; Pizzini, A.; Gatto, V.; Leonardi, L.; Gallo, M.; Brignardello, E.; Boccuzzi, G.

    1997-01-01

    Epidemiological and experimental studies suggest that dehydroepiandrosterone (DHEA) exerts a protective effect against breast cancer. It has been proposed that the non-competitive inhibition of glucose-6-phosphate dehydrogenase (G6PD) contributes to DHEA antitumor action. We evaluated the effects of DHEA on G6PD activity and on the in vitro proliferation of two human breast cancer cell lines, MCF-7 (steroid receptor positive) and MDA-MB-231 (steroid receptor negative), in a serum-free assay. DHEA inhibition of G6PD was only found to occur at concentrations above 10 microM; at these high concentrations, the growth curve was parallel to the enzyme inhibition curve in both cell lines. In contrast, at concentrations in the in vivo breast tissue concentration range, neither cell growth nor enzyme activity was inhibited. The results failed to confirm DHEA's putative anti-tumor action on breast cancer through G6PD inhibition, as the enzyme blockade only becomes apparent at pharmacological concentrations of the steroid. PMID:9052415

  4. Red Cell Glucose-6-Phosphate Dehydrogenase Deficiency—A Newly Recognized Cause of Neonatal Jaundice and Kernicterus in Canada

    PubMed Central

    Naiman, J. Lawrence; Kosoy, Martin H.

    1964-01-01

    Seven male newborns of Chinese, Greek and Italian origin presented with severe hemolytic jaundice due to red cell glucose-6-phosphate dehydrogenase (G-6-PD) deficiency. In five, the hemolysis was precipitated by inhalation of mothball vapours in the home. Kernicterus was evident upon admission in six infants and was fatal in four of these. G-6-PD deficiency should be suspected as a cause of jaundice in all full-term male infants of these ethnic groups. The diagnosis can be confirmed in any hospital by the methemoglobin reduction test. In areas similar to Toronto, Canada, where these high-risk ethnic groups prevail, the following measures are recommended: (1) detection of G-6-PD deficient newborns by screening cord bloods of all infants of these ethnic groups; (2) protection of affected infants from potentially hemolytic agents such as naphthalene, certain vitamin K preparations, and sulfonamides; and (3) observation of serum bilirubin levels to assess the need for exchange transfusion for hyperbilirubinemia. ImagesFig. 1 PMID:14226101

  5. Overexpression, purification and enzymatic characterization of a recombinant plastidial glucose-6-phosphate dehydrogenase from barley (Hordeum vulgare cv. Nure) roots.

    PubMed

    Cardi, Manuela; Chibani, Kamel; Castiglia, Daniela; Cafasso, Donata; Pizzo, Elio; Rouhier, Nicolas; Jacquot, Jean-Pierre; Esposito, Sergio

    2013-12-01

    In plant cells, the plastidial glucose 6-phosphate dehydrogenase (P2-G6PDH, EC 1.1.1.49) represents one of the most important sources of NADPH. However, previous studies revealed that both native and recombinant purified P2-G6PDHs show a great instability and a rapid loss of catalytic activity. Therefore it has been difficult to describe accurately the catalytic and physico-chemical properties of these isoforms. The plastidial G6PDH encoding sequence from barley roots (Hordeum vulgare cv. Nure), devoid of a long plastidial transit peptide, was expressed as recombinant protein in Escherichia coli, either untagged or with an N-terminal his-tag. After purification from both the soluble fraction and inclusion bodies, we have explored its kinetic parameters, as well as its sensitivity to reduction. The obtained results are consistent with values determined for other P2-G6PDHs previously purified from barley roots and from other land plants. Overall, these data shed light on the catalytic mechanism of plant P2-G6PDH, summarized in a proposed model in which the sequential mechanism is very similar to the mammalian cytosolic G6PDH. This study provides a rational basis to consider the recombinant barley root P2-G6PDH as a good model for further kinetic and structural studies.

  6. Regulatory mechanism of the three-component system HptRSA in glucose-6-phosphate uptake in Staphylococcus aureus.

    PubMed

    Yang, Yifan; Sun, Haipeng; Liu, Xiaoyu; Wang, Mingxing; Xue, Ting; Sun, Baolin

    2016-06-01

    Glucose-6-phosphate (G6P) is a common alternative carbon source for various bacteria, and its uptake usually relies on the hexose phosphate antiporter UhpT. In the human pathogenic bacterium Staphylococcus aureus, the ability to utilize different nutrients, particularly alternative carbon source uptake in glucose-limiting conditions, is essential for its fitness in the host environment during the infectious process. It has been reported that G6P uptake in S. aureus is regulated by the three-component system HptRSA. When G6P is provided as the only carbon source, HptRSA could sense extracellular G6P and activate uhpT expression to facilitate G6P utilization. However, the regulatory mechanism of HptRSA is still unclear. In this study, we further investigated the HptRSA system in S. aureus. First, we confirmed that HptRSA is necessary for the normal growth of this pathogen in chemically defined medium with G6P supplementation, and we discovered that HptRSA could exclusively sense extracellular G6P compared to the other organophosphates we tested. Next, using isothermal titration calorimetry, we found that HptA could bind to G6P, suggesting that it may be the G6P sensor. After that experiment, using an electrophoresis mobility shift assay, we verified that the response regulator HptR could directly bind to the uhpT promoter and identified a putative binding site from -67 to -96-bp. Subsequently, we created different point mutations in the putative binding site and revealed that the entire 30-bp sequence is essential for HptR regulation. In summary, we unveiled the regulatory mechanism of the HptRSA system in S. aureus, HptA most likely functions as the G6P sensor, and HptR could implement its regulatory function by directly binding to a conserved, approximately 30-bp sequence in the uhpT promoter.

  7. One-step purification and immobilization of thermophilic polyphosphate glucokinase from Thermobifida fusca YX: glucose-6-phosphate generation without ATP.

    PubMed

    Liao, Hehuan; Myung, Suwan; Zhang, Y-H Percival

    2012-02-01

    The discovery of stable and active polyphosphate glucokinase (PPGK, EC 2.7.1.63) would be vital to cascade enzyme biocatalysis that does not require a costly ATP input. An open reading frame Tfu_1811 from Thermobifida fusca YX encoding a putative PPGK was cloned and the recombinant protein fused with a family 3 cellulose-binding module (CBM-PPGK) was overexpressed in Escherichia coli. Mg²⁺ was an indispensible activator. This enzyme exhibited the highest activity in the presence of 4 mM Mg²⁺ at 55°C and pH 9.0. Under its suboptimal conditions (pH 7.5), the k (cat) and K(m) values of CBM-PPGK on glucose were 96.9 and 39.7 s⁻¹ as well as 0.77 and 0.45 mM at 37°C and 50°C respectively. The thermoinactivation of CBM-PPGK was independent of its mass concentration. Through one-step enzyme purification and immobilization on a high-capacity regenerated amorphous cellulose, immobilized CBM-PPGK had an approximately eightfold half lifetime enhancement (i.e., t(1/2) = 120 min) as compared to free enzyme at 50°C. To our limited knowledge, this enzyme was the first thermostable PPGK reported. Free PPGK and immobilized CBM-PPGK had total turnover number values of 126,000 and 961,000 mol product per mol enzyme, respectively, suggesting their great potential in glucose-6-phosphate generation based on low-cost polyphosphate.

  8. Effects of variant UDP-glucuronosyltransferase 1A1 gene, glucose-6-phosphate dehydrogenase deficiency and thalassemia on cholelithiasis

    PubMed Central

    Huang, Yang-Yang; Huang, Ching-Shui; Yang, Sien-Sing; Lin, Min-Shung; Huang, May-Jen; Huang, Ching-Shan

    2005-01-01

    AIM: To test the hypothesis that the variant UDP-glucuronosyltransferase 1A1 (UGT1A1) gene, glucose-6-phosphate dehydrogenase (G6PD) deficiency, and thalassemia influence bilirubin metabolism and play a role in the development of cholelithiasis. METHODS: A total of 372 Taiwan Chinese with cholelithiasis who had undergone cholecystectomy and 293 healthy individuals were divided into case and control groups, respectively. PCR and restriction fragment length polymorphism were used to analyze the promoter area and nucleotides 211, 686, 1 091, and 1 456 of the UGT1A1 gene for all subjects and the gene variants for thalassemia and G6PD deficiency. RESULTS: Variation frequencies for the cholelithiasis patients were 16.1%, 25.8%, 5.4%, and 4.3% for A(TA)6 TAA/A(TA)7TAA (6/7), heterozygosity within the coding region, compound heterozygosity, and homozygosity of the UGT1A1 gene, respectively. Comparing the case and control groups, a statistically significant difference in frequency was demonstrated for the homozygous variation of the UGT1A1 gene (P = 0.012, χ2 test), but not for the other variations. Further, no difference was demonstrated in a between-group comparison of the incidence of G6PD deficiency and thalassemia (2.7% vs 2.4% and 5.1% vs 5.1%, respectively). The bilirubin levels for the cholelithiasis patients with the homozygous variant-UGT1A1 gene were significantly different from the control analog (18.0 ± 6.5 and 12.7 ± 2.9 μmol/L, respectively; P<0.001, Student’s t test). CONCLUSION: Our results show that the homozygous variation in the UGT1A1 gene is a risk factor for the development of cholelithiasis in Taiwan Chinese. PMID:16237771

  9. Prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency in the Ouest and Sud-Est departments of Haiti.

    PubMed

    von Fricken, Michael E; Weppelmann, Thomas A; Eaton, Will T; Alam, Meer T; Carter, Tamar E; Schick, Laura; Masse, Roseline; Romain, Jean R; Okech, Bernard A

    2014-07-01

    Malaria remains a significant public health issue in Haiti, with chloroquine (CQ) used almost exclusively for the treatment of uncomplicated infections. Recently, single dose primaquine (PQ) was added to the Haitian national malaria treatment policy, despite a lack of information on the prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency within the population. G6PD deficient individuals who take PQ are at risk of developing drug induced hemolysis (DIH). In this first study to examine G6PD deficiency rates in Haiti, 22.8% (range 14.9%-24.7%) of participants were found to be G6PD deficient (class I, II, or III) with 2.0% (16/800) of participants having severe deficiency (class I and II). Differences in deficiency were observed by gender, with males having a much higher prevalence of severe deficiency (4.3% vs. 0.4%) compared to females. Male participants were 1.6 times more likely to be classified as deficient and 10.6 times more likely to be classified as severely deficient compared to females, as expected. Finally, 10.6% (85/800) of the participants were considered to be at risk for DIH. Males also had much higher rates than females (19.3% vs. 4.6%) with 4.9 times greater likelihood (p value 0.000) of having an activity level that could lead to DIH. These findings provide useful information to policymakers and clinicians who are responsible for the implementation of PQ to control and manage malaria in Haiti. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Hematological parameters and red blood cell morphological abnormality of Glucose-6-Phosphate dehydrogenase deficiency co-inherited with thalassemia.

    PubMed

    Pengon, Jutharat; Svasti, Saovaros; Kamchonwongpaisan, Sumalee; Vattanaviboon, Phantip

    2017-06-15

    Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency and thalassemia are genetically independent hemolytic disorders. Co-inheritance of both disorders may affect red blood cell pathology to a greater extent than normally seen in either disorder alone. This study determines the prevalence and evaluates hematological changes of G-6-PD deficiency and thalassemia co-inheritance. G-6-PD deficiency was screened from 200 male thalassemia blood samples using a fluorescent spot test. Hematological parameters and red blood cell morphology were evaluated among G-6-PD deficiency/thalassemia co-inheritance, G-6-PD deficiency alone, thalassemia alone, and normal individuals. G-6-PD deficiency was detected together with hemoglobin (Hb) E heterozygote, Hb E homozygote, β-thalassemia trait, and β-thalassemia/Hb E, α-thalassemia-2 trait, and Hb H disease. Hb level, hematocrit, mean cell volume, and mean cell Hb of G-6-PD deficiency co-inherited with asymptomatic thalassemia carriers show significantly lower mean values compared to carriers with only the same thalassemia genotypes. Higher mean red blood cell distribution width was observed in G-6-PD deficiency co-inherited with Hb E heterozygote, as with numbers of hemighost cells in G-6-PD deficiency/thalassemia co-inheritance compared to those with either disorder. Apart from Hb level, hematological parameters of co-inheritance disorders were not different from individuals with a single thalassemia disease. G-6-PD deficiency co-inherited with thalassemia in males was present in 10% of the participants, resulting in worsening of red blood cell pathology compared with inheritance of thalassemia alone. Copyright © 2017 King Faisal Specialist Hospital & Research Centre. Published by Elsevier B.V. All rights reserved.

  11. Autosomal factors with correlated effects on the activities of the glucose 6-phosphate and 6-phosphogluconate dehydrogenases in Drosophila melanogaster.

    PubMed

    Laurie-Ahlberg, C C; Williamson, J H; Cochrane, B J; Wilton, A N; Chasalow, F I

    1981-09-01

    Isogenic lines, in which chromosomes sampled from natural populations of C. melanogaster are substituted into a common genetic background, were used to detect and partially characterize autosomal factors that affect the activities of the two pentose phosphate pathway enzymes, glucose 6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD). The chromosome 3 effects on G6PD and 6PGD are clearly correlated; the chromosome 2 effects, which are not so great, also appear to be correlated, but the evidence in this case is not so strong. Examination of activity variation of ten other enzymes revealed that G6PD and 6PGD are not the only pair of enzymes showing a high positive correlation, but it is among the highest in both sets of lines. In addition, there was some evidence that the factor(s) affecting G6PD and 6PGD may also affect two other metabolically related enzymes, transaldolase and phosphoglucose isomerase.--Rocket immunoelectrophoresis was used to estimate specific CRM levels for three of the enzymes studied: G6PD, 6PGD and ME. This experiment shows that a large part of the activity variation is accounted for by variation in CRM level (especially for chromosome 3 lines), but there remains a significant fraction of the genetic component of activity variation that is not explained by CRM level.--These results suggest that the autosomal factors are modifiers involved in regulation of the expression of the X-linked structural genes for G6PD and 6PGD, but a role in determining part of the enzymes' primary structure cannot be excluded with the present evidence.

  12. Autosomal Factors with Correlated Effects on the Activities of the Glucose 6-Phosphate and 6-Phosphogluconate Dehydrogenases in DROSOPHILA MELANOGASTER

    PubMed Central

    Laurie-Ahlberg, C. C.; Williamson, J. H.; Cochrane, B. J.; Wilton, A. N.; Chasalow, F. I.

    1981-01-01

    Isogenic lines, in which chromosomes sampled from natural populations of D. melanogaster are substituted into a common genetic background, were used to detect and partially characterize autosomal factors that affect the activities of the two pentose phosphate pathway enzymes, glucose 6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD). The chromosome 3 effects on G6PD and 6PGD are clearly correlated; the chromosome 2 effects, which are not so great, also appear to be correlated, but the evidence in this case is not so strong. Examination of activity variation of ten other enzymes revealed that G6PD and 6PGD are not the only pair of enzymes showing a high positive correlation, but it is among the highest in both sets of lines. In addition, there was some evidence that the factor(s) affecting G6PD and 6PGD may also affect two other metabolically related enzymes, transaldolase and phosphoglucose isomerase.—Rocket immunoelectrophoresis was used to estimate specific CRM levels for three of the enzymes studied: G6PD, 6PGD and ME. This experiment shows that a large part of the activity variation is accounted for by variation in CRM level (especially for chromosome 3 lines), but there remains a significant fraction of the genetic component of activity variation that is not explained by CRM level.—These results suggest that the autosomal factors are modifiers involved in regulation of the expression of the X-linked structural genes for G6PD and 6PGD, but a role in determining part of the enzymes' primary structure cannot be excluded with the present evidence. PMID:6804300

  13. A population survey of the glucose-6-phosphate dehydrogenase (G6PD) 563C>T (Mediterranean) mutation in Afghanistan.

    PubMed

    Jamornthanyawat, Natsuda; Awab, Ghulam R; Tanomsing, Naowarat; Pukrittayakamee, Sasithon; Yamin, Fazel; Dondorp, Arjen M; Day, Nicholas P J; White, Nicholas J; Woodrow, Charles J; Imwong, Mallika

    2014-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common inherited enzyme defect and an important problem in areas with Plasmodium vivax infection because of the risk of haemolysis following administration of primaquine to treat the liver forms of the parasite. We undertook a genotypic survey of 713 male individuals across nine provinces of Afghanistan in which malaria is found, four in the north and five in the east. RFLP typing at nucleotide position 563 detected 40 individuals with the Mediterranean mutation 563C>T, an overall prevalence of 5.6%. This varied according to self-reported ethnicity, with prevalence in the Pashtun/Pashai group of 33/369 (8.9%) compared to 7/344 individuals in the rest of the population (2.0%; p<0.001, Chi-squared test). Multivariate analysis of ethnicity and geographical location indicated an adjusted odds ratio of 3.50 (95% CI 1.36-9.02) for the Pashtun/Pashai group, while location showed only a trend towards higher prevalence in eastern provinces (adjusted odds ratio = 1.73, 0.73-4.13). Testing of known polymorphic markers (1311C>T in exon 11, and C93T in intron XI) in a subset of 82 individuals wild-type at C563 revealed a mixture of 3 haplotypes in the background population and was consistent with data from the 1000 Genomes Project and published studies. By comparison individuals with G6PD deficiency showed a highly skewed haplotype distribution, with 95% showing the CT haplotype, a finding consistent with relatively recent appearance and positive selection of the Mediterranean variant in Afghanistan. Overall, the data confirm that the Mediterranean variant of G6PD is common in many ethnic groups in Afghanistan, indicating that screening for G6PD deficiency is required in all individuals before radical treatment of P. vivax with primaquine.

  14. Diverse point mutations in the human glucose-6-phosphate dehydrogenase gene cause enzyme deficiency and mild or severe hemolytic anemia.

    PubMed Central

    Vulliamy, T J; D'Urso, M; Battistuzzi, G; Estrada, M; Foulkes, N S; Martini, G; Calabro, V; Poggi, V; Giordano, R; Town, M

    1988-01-01

    Glucose-6-phosphate dehydrogenase (G6PD; EC 1.1.1.49) deficiency is a common genetic abnormality affecting an estimated 400 million people worldwide. Clinical and biochemical analyses have identified many variants exhibiting a range of phenotypes, which have been well characterized from the hematological point of view. However, until now, their precise molecular basis has remained unknown. We have cloned and sequenced seven mutant G6PD alleles. In the nondeficient polymorphic African variant G6PD A we have found a single point mutation. The other six mutants investigated were all associated with enzyme deficiency. In one of the commonest, G6PD Mediterranean, which is associated with favism among other clinical manifestations, a single amino acid replacement was found (serine----phenylalanine): it must be responsible for the decreased stability and the reduced catalytic efficiency of this enzyme. Single point mutations were also found in G6PD Metaponto (Southern Italy) and in G6PD Ilesha (Nigeria), which are asymptomatic, and in G6PD Chatham, which was observed in an Indian boy with neonatal jaundice. In G6PD "Matera," which is now known to be the same as G6PD A-, two separate point mutations were found, one of which is the same as in G6PD A. In G6PD Santiago, a de novo mutation (glycine----arginine) is associated with severe chronic hemolytic anemia. The mutations observed show a striking predominance of C----T transitions, with CG doublets involved in four of seven cases. Thus, diverse point mutations may account largely for the phenotypic heterogeneity of G6PD deficiency. Images PMID:3393536

  15. A Population Survey of the Glucose-6-Phosphate Dehydrogenase (G6PD) 563C>T (Mediterranean) Mutation in Afghanistan

    PubMed Central

    Jamornthanyawat, Natsuda; Awab, Ghulam R.; Tanomsing, Naowarat; Pukrittayakamee, Sasithon; Yamin, Fazel; Dondorp, Arjen M.; Day, Nicholas P. J.; White, Nicholas J.; Woodrow, Charles J.; Imwong, Mallika

    2014-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common inherited enzyme defect and an important problem in areas with Plasmodium vivax infection because of the risk of haemolysis following administration of primaquine to treat the liver forms of the parasite. We undertook a genotypic survey of 713 male individuals across nine provinces of Afghanistan in which malaria is found, four in the north and five in the east. RFLP typing at nucleotide position 563 detected 40 individuals with the Mediterranean mutation 563C>T, an overall prevalence of 5.6%. This varied according to self-reported ethnicity, with prevalence in the Pashtun/Pashai group of 33/369 (8.9%) compared to 7/344 individuals in the rest of the population (2.0%; p<0.001, Chi-squared test). Multivariate analysis of ethnicity and geographical location indicated an adjusted odds ratio of 3.50 (95% CI 1.36–9.02) for the Pashtun/Pashai group, while location showed only a trend towards higher prevalence in eastern provinces (adjusted odds ratio = 1.73, 0.73–4.13). Testing of known polymorphic markers (1311C>T in exon 11, and C93T in intron XI) in a subset of 82 individuals wild-type at C563 revealed a mixture of 3 haplotypes in the background population and was consistent with data from the 1000 Genomes Project and published studies. By comparison individuals with G6PD deficiency showed a highly skewed haplotype distribution, with 95% showing the CT haplotype, a finding consistent with relatively recent appearance and positive selection of the Mediterranean variant in Afghanistan. Overall, the data confirm that the Mediterranean variant of G6PD is common in many ethnic groups in Afghanistan, indicating that screening for G6PD deficiency is required in all individuals before radical treatment of P. vivax with primaquine. PMID:24586352

  16. Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency in Greek newborns: the Mediterranean C563T mutation screening.

    PubMed

    Molou, Elina; Schulpis, Kleopatra H; Thodi, Georgia; Georgiou, Vassiliki; Dotsikas, Yannis; Papadopoulos, Konstantinos; Biti, Sofia; Loukas, Yannis L

    2014-04-01

    Glucose-6-Phosphate Dehydrogenase (G6PD) gene is located at the X-chromosome at Xq28 and the disease is recessively inherited predominantly in males. More than 400 variants have been proposed based on clinical and enzymatic studies. The aim of the current study was to identify C563T mutation in G6PD-deficient newborns and to correlate the enzyme residual activity with the presence of the mutation. Some 1189 full-term neonates aged 3-5 days old were tested for G6PD activity in dried blood spots from Guthrie cards using a commercial kit. DNA extraction from Guthrie cards and mutation identification among the deficient samples were performed with current techniques. A total of 92 (7.7%) newborns were G6PD-deficient. In 46 (50%), the mutation C563T was identified. The residual activity in C563T hemizygote males (n = 28) was statistically significantly lower (1.23 ± 0.93 U/g Hb) than that in non-C563T G6PD-deficient males (n = 25) (4.01 ± 1.20 U/g Hb, p < 0.0001) and in controls (13.6 ± 2.9 U/g Hb, p < 0.0001). In C563T heterozygote females, the estimated enzyme activity was lower than that determined in non-C563T females. Male C563T hemizygotes suffer from G6PD deficiency and severe neonatal jaundice. G6PD activity showed statistically significant correlation with total bilirubin blood levels.

  17. Screening for Glucose-6-Phosphate Dehydrogenase Deficiency Using Three Detection Methods: A Cross-Sectional Survey in Southwestern Uganda.

    PubMed

    Roh, Michelle E; Oyet, Caesar; Orikiriza, Patrick; Wade, Martina; Mwanga-Amumpaire, Juliet; Boum, Yap; Kiwanuka, Gertrude N; Parikh, Sunil

    2016-11-02

    Despite the potential benefit of primaquine in reducing Plasmodium falciparum transmission and radical cure of Plasmodium vivax and Plasmodium ovale infections, concerns over risk of hemolytic toxicity in individuals with glucose-6-phosphate dehydrogenase deficiency (G6PDd) have hampered its deployment. A cross-sectional survey was conducted in 2014 to assess the G6PDd prevalence among 631 children between 6 and 59 months of age in southwestern Uganda, an area where primaquine may be a promising control measure. G6PDd prevalence was determined using three detection methods: a quantitative G6PD enzyme activity assay (Trinity Biotech(®) G-6-PDH kit), a qualitative point-of-care test (CareStart(™) G6PD rapid diagnostic test [RDT]), and molecular detection of the G6PD A- G202A allele. Qualitative tests were compared with the gold standard quantitative assay. G6PDd prevalence was higher by RDT (8.6%) than by quantitative assay (6.8%), using a < 60% activity threshold. The RDT performed optimally at a < 60% threshold and demonstrated high sensitivity (≥ 90%) and negative predictive values (100%) across three activity thresholds (below 60%, 30%, and 40%). G202A allele frequency was 6.4%, 7.9%, and 6.8% among females, males, and overall, respectively. Notably, over half of the G202A homo-/hemizygous children expressed ≥ 60% enzyme activity. Overall, the CareStart(™) G6PD RDT appears to be a viable screening test to accurately identify individuals with enzyme activities below 60%. The low prevalence of G6PDd across all three diagnostic modalities and absence of severe deficiency in our study suggests that there is little barrier to the use of single-dose primaquine in this region.

  18. Prevalence of glucose-6-phosphate dehydrogenase deficiency and diagnostic challenges in 1500 immigrants in Denmark examined for haemoglobinopathies.

    PubMed

    Warny, Marie; Klausen, Tobias Wirenfeldt; Petersen, Jesper; Birgens, Henrik

    2015-09-01

    Similar to the thalassaemia syndromes, glucose-6-phosphate dehydrogenase (G6PD) deficiency is highly prevalent in areas historically exposed to malaria. In the present study, we used quantitative and molecular methods to determine the prevalence of G6PD deficiency in a population of 1508 immigrants in Denmark. We found the allele frequency to be between 2.4 and 2.9% in the female immigrants. Furthermore, the mutation pattern in the studied population showed a high prevalence of the G6PD A-(202A) variant in African and African-American immigrants, a high prevalence of the G6PD Mediterranean variant in Mediterranean European and Western Asian immigrants, and substantial heterogeneity in the variants found in the Eastern Asian/Pacific immigrants. Inasmuch as many of the patients included in this investigation had various thalassaemic syndromes, we were able to evaluate the effects of the interaction between a low mean corpuscular haemoglobin (MCH) value and G6PD activity, particularly in heterozygous females. The activity level was markedly influenced by the MCH value in females with normal G6PD activity, but not in heterozygous and homozygous females. Comparison of patients with normal G6PD activity and heterozygous females indicated considerable overlap in activity levels. To help separating heterozygous females from females with wild-type genes, a DNA analysis is necessary when the female activity level is between 4.0 and 4.9 U/g hgb corresponding to 50-60% of the median activity of unaffected males.

  19. Knockdown of glucose-6-phosphate dehydrogenase (G6PD) following cerebral ischemic reperfusion: the pros and cons.

    PubMed

    Zhao, Gang; Zhao, Yanxin; Wang, Xingyu; Xu, Ying

    2012-07-01

    NADPH derived from glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway, has been implicated not only to promote reduced glutathione (GSH) but also enhance oxidative stress in specific cellular conditions. In this study, the effects of G6PD antisense oligodeoxynucleotides (AS-ODNs) was examined on the CA1 pyramidal neurons following transient cerebral ischemia. Specifically knockdown of G6PD protein expression in hippocampus CA1 subregion at early reperfusion period (1-24 h) with a strategy to pre-treated G6PD AS-ODNs significantly reduced G6PD activity and NADPH level, an effect correlated with attenuation of NADPH oxidase activation and superoxide anion production. Concomitantly, pre-treatment of G6PD AS-ODNs markedly reduced oxidative DNA damage and the delayed neuronal cell death in rat hippocampal CA1 region induced by global cerebral ischemia. By contrast, knockdown of G6PD protein at late reperfusion period (48-96 h) increased oxidative DNA damage and exacerbated the ischemia-induced neuronal cell death in hippocampal CA1 region, an effect associated with reduced NADPH level and GSH/GSSG ratio. These findings indicate that G6PD not only plays a role in oxidative neuronal damage but also a neuroprotective role during different ischemic reperfusion period. Therefore, G6PD mediated oxidative response and redox regulation in the hippocampal CA1 act as the two sides of the same coin and may represent two potential applications of G6PD during different stage of cerebral ischemic reperfusion. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency in southeast Iran: implications for malaria elimination.

    PubMed

    Tabatabaei, Seyed Mehdi; Salimi Khorashad, Alireza; Sakeni, Mohammad; Raeisi, Ahmad; Metanat, Zahra

    2015-03-15

    Glucose-6-phosphate dehydrogenase deficiency (G6PD) is an X-linked genetic disorder with a relatively high frequency in malaria-endemic regions. It is an obstacle to malaria elimination, as primaquine administered in the treatment of malaria can cause hemolysis in G6PD-deficient individuals. This study presents information on the prevalence of G6PD deficiency in Sistan and Balouchetsan province, which hosts more than 90% of Plasmodium vivax malaria cases in Iran. This type of information is needed for a successful malaria elimination program. A total of 526 students were randomly recruited through schools located in southeast Iran. Information was collected by interviewing the students using a structured questionnaire. Blood samples taken on filter papers were examined for G6PD deficiency using the fluorescent spot test. Overall, 72.8% (383/526) of the subjects showed normal G6PD enzyme function. Mild and severe G6PD deficiency was observed in 14.8% (78) and 12.2% (64) of subjects, respectively. A total 193/261 males (73.9%) and 190/265 (72%) females had normal enzyme activity. Mild G6PD deficiency was observed in 10.8% (28) and 18.9% (50) of male and female subjects, respectively. However, in comparison with females, a greater proportion of males showed severe enzyme deficiency (15.3% versus 9.1%). All these differences were statistically significant (p < 0.006). G6PD deficiency is highly prevalent in southeast Iran. G6PD-deficient individuals are susceptible to potentially severe and life-threatening hemolytic reactions after primaquine treatment. In order to achieve malaria elimination goals in the province, G6PD testing needs to be made routinely available within the health system.

  1. Impact of glucose-6-phosphate dehydrogenase deficiency on sickle cell anaemia expression in infancy and early childhood: a prospective study.

    PubMed

    Benkerrou, Malika; Alberti, Corinne; Couque, Nathalie; Haouari, Zinedine; Ba, Aissatou; Missud, Florence; Boizeau, Priscilla; Holvoet, Laurent; Ithier, Ghislaine; Elion, Jacques; Baruchel, André; Ducrocq, Rolande

    2013-12-01

    In patients with sickle cell anaemia (SCA), concomitant glucose-6-phosphate dehydrogenase (G6PD) deficiency is usually described as having no effect and only occasionally as increasing severity. We analysed sequential clinical and biological data for the first 42 months of life in SCA patients diagnosed by neonatal screening, including 27 G6PD-deficient patients, who were matched on sex, age and parents' geographic origin to 81 randomly selected patients with normal G6PD activity. In the G6PD-deficient group, steady-state haemoglobin was lower (-6·2 g/l, 95% confidence interval (CI), [-10·1; -2·3]) and reticulocyte count higher (247 × 10(9) /l, 95%CI, [97; 397]). The acute anaemic event rate was 3 times higher in the G6PD-deficient group (P < 10(-3) ). A higher proportion of G6PD-deficient patients required blood transfusion (20/27 [74%] vs. 37/81 [46%], P < 10(-3) ), for acute anaemic events, and also vaso-occlusive and infectious events. No significant between-group differences were found regarding the rates of vaso-occlusive, infectious, or cerebrovascular events. G6PD deficiency in babies with SCA worsens anaemia and increases blood transfusion requirements in the first years of life. These effects decrease after 2 years of age, presumably as the decline in fetal haemoglobin levels leads to increased sickle cell haemolysis and younger red blood cells with higher G6PD activity. © 2013 John Wiley & Sons Ltd.

  2. The level of glucose-6-phosphate dehydrogenase activity strongly influences xylose fermentation and inhibitor sensitivity in recombinant Saccharomyces cerevisiae strains.

    PubMed

    Jeppsson, Marie; Johansson, Björn; Jensen, Peter Ruhdal; Hahn-Hägerdal, Bärbel; Gorwa-Grauslund, Marie F

    2003-11-01

    Disruption of the ZWF1 gene encoding glucose-6-phosphate dehydrogenase (G6PDH) has been shown to reduce the xylitol yield and the xylose consumption in the xylose-utilizing recombinant Saccharomyces cerevisiae strain TMB3255. In the present investigation we have studied the influence of different production levels of G6PDH on xylose fermentation. We used a synthetic promoter library and the copper-regulated CUP1 promoter to generate G6PDH-activities between 0% and 179% of the wild-type level. G6PDH-activities of 1% and 6% of the wild-type level resulted in 2.8- and 5.1-fold increase in specific xylose consumption, respectively, compared with the ZWF1-disrupted strain. Both strains exhibited decreased xylitol yields (0.13 and 0.19 g/g xylose) and enhanced ethanol yields (0.36 and 0.34 g/g xylose) compared with the control strain TMB3001 (0.29 g xylitol/g xylose, 0.31 g ethanol/g xylose). Cytoplasmic transhydrogenase (TH) from Azotobacter vinelandii has previously been shown to transfer NADPH and NAD(+) into NADP(+) and NADH, and TH-overproduction resulted in lower xylitol yield and enhanced glycerol yield during xylose utilization. Strains with low G6PDH-activity grew slower in a lignocellulose hydrolysate than the strain with wild-type G6PDH-activity, which suggested that the availability of intracellular NADPH correlated with tolerance towards lignocellulose-derived inhibitors. Low G6PDH-activity strains were also more sensitive to H(2)O(2) than the control strain TMB3001.

  3. Should blood donors be routinely screened for glucose-6-phosphate dehydrogenase deficiency? A systematic review of clinical studies focusing on patients transfused with glucose-6-phosphate dehydrogenase-deficient red cells.

    PubMed

    Renzaho, Andre M N; Husser, Eliette; Polonsky, Michael

    2014-01-01

    The risk factors associated with the use of glucose-6-phosphate dehydrogenase (G6PD)-deficient blood in transfusion have not yet been well established. Therefore, the aim of this review was to evaluate whether whole blood from healthy G6PD-deficient donors is safe to use for transfusion. The study undertook a systematic review of English articles indexed in COCHRANE, MEDLINE, EMBASE, and CINHAL, with no date restriction up to March 2013, as well as those included in articles' reference lists and those included in Google Scholar. Inclusion criteria required that studies be randomized controlled trials, case controls, case reports, or prospective clinical series. Data were extracted following the Preferred Reporting Items for Systematic Reviews using a previously piloted form, which included fields for study design, population under study, sample size, study results, limitations, conclusions, and recommendations. The initial search identified 663 potentially relevant articles, of which only 13 studies met the inclusion criteria. The reported effects of G6PD-deficient transfused blood on neonates and children appear to be more deleterious than effects reported on adult patients. In most cases, the rise of total serum bilirubin was abnormal in infants transfused with G6PD-deficient blood from 6 hours up to 60 hours after transfusion. All studies on neonates and children, except one, recommended a routine screening for G6PD deficiency for this at-risk subpopulation because their immature hepatic function potentially makes them less able to handle any excess bilirubin load. It is difficult to make firm clinical conclusions and recommendations given the equivocal results, the lack of standardized evaluation methods to categorize red blood cell units as G6PD deficient (some of which are questionable), and the limited methodological quality and low quality of evidence. Notwithstanding these limitations, based on our review of the available literature, there is little to

  4. Data on how several physiological parameters of stored red blood cells are similar in glucose 6-phosphate dehydrogenase deficient and sufficient donors.

    PubMed

    Tzounakas, Vassilis L; Kriebardis, Anastasios G; Georgatzakou, Hara T; Foudoulaki-Paparizos, Leontini E; Dzieciatkowska, Monika; Wither, Matthew J; Nemkov, Travis; Hansen, Kirk C; Papassideri, Issidora S; D'Alessandro, Angelo; Antonelou, Marianna H

    2016-09-01

    This article contains data on the variation in several physiological parameters of red blood cells (RBCs) donated by eligible glucose-6-phosphate dehydrogenase (G6PD) deficient donors during storage in standard blood bank conditions compared to control, G6PD sufficient (G6PD(+)) cells. Intracellular reactive oxygen species (ROS) generation, cell fragility and membrane exovesiculation were measured in RBCs throughout the storage period, with or without stimulation by oxidants, supplementation of N-acetylcysteine and energy depletion, following incubation of stored cells for 24 h at 37 °C. Apart from cell characteristics, the total or uric acid-dependent antioxidant capacity of the supernatant in addition to extracellular potassium concentration was determined in RBC units. Finally, procoagulant activity and protein carbonylation levels were measured in the microparticles population. Further information can be found in "Glucose 6-phosphate dehydrogenase deficient subjects may be better "storers" than donors of red blood cells" [1].

  5. Glucose-6-phosphate dehydrogenase deficiency among children attending the Emergency Paediatric Unit of Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria.

    PubMed

    Isaac, Iz; Mainasara, As; Erhabor, Osaro; Omojuyigbe, St; Dallatu, Mk; Bilbis, Ls; Adias, Tc

    2013-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common human enzyme deficiencies in the world. It is particularly common in populations living in malaria-endemic areas, affecting more than 400 million people worldwide. This present study was conducted with the aim of determining the prevalence of G6PD deficiency among children visiting the Emergency Paediatric Unit of Usmanu Danfodiyo University Teaching Hospital for pediatric-related care. The study included 118 children, made up of 77 (65.3%) males and 41 (34.7%) females aged ≤5 years with mean age of 3.26 ± 1.90 years. Randox G6PD quantitative in vitro test screening was used for the diagnosis of G6PD deficiency. Of the 118 children tested, 17 (14.4%) were G6PD-deficient. Prevalence of G6PD deficiency was concentrated predominantly among male children (22.1%). Male sex was significantly correlated with G6PD deficiency among the children studied (r = 7.85, P = 0.01). The highest prevalence occurred among children in the 2- to 5-year age-group. Of the 17 G6PD-deficient children, twelve (70.2%) were moderately deficient, while five (29.4%) were severely deficient. Blood film from G6PD-deficient children indicated the following morphological changes; Heinz bodies, schistocytes, target cells, nucleated red cells, spherocytes, and polychromasia. This present study has shown a high prevalence of G6PD deficiency among children residing in Sokoto in the northwestern geopolitical zone of Nigeria. The study indicated a male sex bias in the prevalence of G6PD deficiency among the children studied. There is a need for the routine screening of children for G6PD deficiency in our environment, to allow for evidence-based management of these children and to ensure the avoidance of food, drugs, and infective agents that can potentially predispose these children to oxidative stress as well as diseases that deplete micronutrients that protect against oxidative stress. There is need to build capacity in our

  6. Determinants of Cofactor Specificity for the Glucose-6-Phosphate Dehydrogenase from Escherichia coli: Simulation, Kinetics and Evolutionary Studies

    PubMed Central

    Fuentealba, Matias; Muñoz, Rodrigo; Maturana, Pablo; Krapp, Adriana; Cabrera, Ricardo

    2016-01-01

    Glucose 6-Phosphate Dehydrogenases (G6PDHs) from different sources show varying specificities towards NAD+ and NADP+ as cofactors. However, it is not known to what extent structural determinants of cofactor preference are conserved in the G6PDH family. In this work, molecular simulations, kinetic characterization of site-directed mutants and phylogenetic analyses were used to study the structural basis for the strong preference towards NADP+ shown by the G6PDH from Escherichia coli. Molecular Dynamics trajectories of homology models showed a highly favorable binding energy for residues K18 and R50 when interacting with the 2'-phosphate of NADP+, but the same residues formed no observable interactions in the case of NAD+. Alanine mutants of both residues were kinetically characterized and analyzed with respect to the binding energy of the transition state, according to the kcat/KM value determined for each cofactor. Whereas both residues contribute to the binding energy of NADP+, only R50 makes a contribution (about -1 kcal/mol) to NAD+ binding. In the absence of both positive charges the enzyme was unable to discriminate NADP+ from NAD+. Although kinetic data is sparse, the observed distribution of cofactor preferences within the phylogenetic tree is sufficient to rule out the possibility that the known NADP+-specific G6PDHs form a monophyletic group. While the β1-α1 loop shows no strict conservation of K18, (rather, S and T seem to be more frequent), in the case of the β2-α2 loop, different degrees of conservation are observed for R50. Noteworthy is the fact that a K18T mutant is indistinguishable from K18A in terms of cofactor preference. We conclude that the structural determinants for the strict discrimination against NAD+ in the case of the NADP+-specific enzymes have evolved independently through different means during the evolution of the G6PDH family. We further suggest that other regions in the cofactor binding pocket, besides the β1-α1 and β2-α2

  7. Glucose-6-phosphate dehydrogenase regulation in the hepatopancreas of the anoxia-tolerant marine mollusc, Littorina littorea.

    PubMed

    Lama, Judeh L; Bell, Ryan A V; Storey, Kenneth B

    2013-01-01

    Glucose-6-phosphate dehydrogenase (G6PDH) gates flux through the pentose phosphate pathway and is key to cellular antioxidant defense due to its role in producing NADPH. Good antioxidant defenses are crucial for anoxia-tolerant organisms that experience wide variations in oxygen availability. The marine mollusc, Littorina littorea, is an intertidal snail that experiences daily bouts of anoxia/hypoxia with the tide cycle and shows multiple metabolic and enzymatic adaptations that support anaerobiosis. This study investigated the kinetic, physical and regulatory properties of G6PDH from hepatopancreas of L. littorea to determine if the enzyme is differentially regulated in response to anoxia, thereby providing altered pentose phosphate pathway functionality under oxygen stress conditions. Several kinetic properties of G6PDH differed significantly between aerobic and 24 h anoxic conditions; compared with the aerobic state, anoxic G6PDH (assayed at pH 8) showed a 38% decrease in K m G6P and enhanced inhibition by urea, whereas in pH 6 assays K m NADP and maximal activity changed significantly between the two states. The mechanism underlying anoxia-responsive changes in enzyme properties proved to be a change in the phosphorylation state of G6PDH. This was documented with immunoblotting using an anti-phosphoserine antibody, in vitro incubations that stimulated endogenous protein kinases versus protein phosphatases and significantly changed K m G6P, and phosphorylation of the enzyme with (32)P-ATP. All these data indicated that the aerobic and anoxic forms of G6PDH were the high and low phosphate forms, respectively, and that phosphorylation state was modulated in response to selected endogenous protein kinases (PKA or PKG) and protein phosphatases (PP1 or PP2C). Anoxia-induced changes in the phosphorylation state of G6PDH may facilitate sustained or increased production of NADPH to enhance antioxidant defense during long term anaerobiosis and/or during the transition

  8. Determinants of Cofactor Specificity for the Glucose-6-Phosphate Dehydrogenase from Escherichia coli: Simulation, Kinetics and Evolutionary Studies.

    PubMed

    Fuentealba, Matias; Muñoz, Rodrigo; Maturana, Pablo; Krapp, Adriana; Cabrera, Ricardo

    2016-01-01

    Glucose 6-Phosphate Dehydrogenases (G6PDHs) from different sources show varying specificities towards NAD+ and NADP+ as cofactors. However, it is not known to what extent structural determinants of cofactor preference are conserved in the G6PDH family. In this work, molecular simulations, kinetic characterization of site-directed mutants and phylogenetic analyses were used to study the structural basis for the strong preference towards NADP+ shown by the G6PDH from Escherichia coli. Molecular Dynamics trajectories of homology models showed a highly favorable binding energy for residues K18 and R50 when interacting with the 2'-phosphate of NADP+, but the same residues formed no observable interactions in the case of NAD+. Alanine mutants of both residues were kinetically characterized and analyzed with respect to the binding energy of the transition state, according to the kcat/KM value determined for each cofactor. Whereas both residues contribute to the binding energy of NADP+, only R50 makes a contribution (about -1 kcal/mol) to NAD+ binding. In the absence of both positive charges the enzyme was unable to discriminate NADP+ from NAD+. Although kinetic data is sparse, the observed distribution of cofactor preferences within the phylogenetic tree is sufficient to rule out the possibility that the known NADP+-specific G6PDHs form a monophyletic group. While the β1-α1 loop shows no strict conservation of K18, (rather, S and T seem to be more frequent), in the case of the β2-α2 loop, different degrees of conservation are observed for R50. Noteworthy is the fact that a K18T mutant is indistinguishable from K18A in terms of cofactor preference. We conclude that the structural determinants for the strict discrimination against NAD+ in the case of the NADP+-specific enzymes have evolved independently through different means during the evolution of the G6PDH family. We further suggest that other regions in the cofactor binding pocket, besides the β1-α1 and β2-α2

  9. Effect of peptides of the insulin superfamily on glucose-6-phosphate dehydrogenase activity in skeletal muscles of river lamprey (Lampetra fluviatilis) during prespawning starvation.

    PubMed

    Chistyakova, O V; Kuznetsova, L A

    2009-07-01

    Glucose-6-phosphate dehydrogenase activity in skeletal muscles of the lamprey (Lampetra fluviatilis) decreased during prespawning starvation (September-May). The observed changes were particularly pronounced in January. Insulin, insulin-like growth factor 1, and relaxin produce an in vitro stimulatory effect on the enzyme. Insulin was most potent in this respect. Inactivation of the enzyme was accompanied by a decrease in its sensitivity to the stimulatory effect of insulin and insulin-like growth factor 1.

  10. Acute viral hepatitis E presenting with haemolytic anaemia and acute renal failure in a patient with glucose-6-phosphate dehydrogenase deficiency.

    PubMed

    Tomar, Laxmikant Ramkumarsingh; Aggarwal, Amitesh; Jain, Piyush; Rajpal, Surender; Agarwal, Mukul P

    2015-10-01

    The association of acute hepatitis E viral (HEV) infection with glucose-6-phosphate dehydrogenase (G6PD) deficiency leading to extensive intravascular haemolysis is a very rare clinical entity. Here we discuss such a patient, who presented with acute HEV illness, developed severe intravascular haemolysis and unusually high levels of bilirubin, complicated by acute renal failure (ARF), and was later on found to have a deficiency of G6PD. The patient recovered completely with haemodialysis and supportive management.

  11. Glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides is a reliable internal standard for radiation-inactivation studies of membranes in the frozen state

    SciTech Connect

    McIntyre, J.O.; Churchill, P.

    1985-06-01

    The target size of four soluble enzymes (beta-galactosidase, pyruvate kinase, alcohol dehydrogenase, and glucose-6-phosphate dehydrogenase) in the presence or absence of subcellular membrane fractions has been determined by the radiation-inactivation method using samples in the frozen state. For each of the four enzymes, full activity was recovered after freezing and thawing in the absence of radiation. The authors found minimal (less than 20%) binding of the enzymes to either submitochondrial vesicles or sarcoplasmic reticulum vesicles. Under the conditions tested, beta-galactosidase, pyruvate kinase, and alcohol dehydrogenase exhibited target sizes which varied according to the experimental conditions, i.e., the buffer selected and also the presence or absence of membrane preparations. For these tetrameric enzymes, the target sizes were generally comparable to either a monomer or a dimer. By contrast, the target size of glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides was found to be essentially invariant when frozen in a variety of buffers and in the presence or absence of either cryoprotectant (sucrose or glycerol) or different membrane preparations. The target size from 19 separate determinations gave an average value of 104 +/- 16 kDa, which is comparable to the molecular weight of the enzyme (104 kDa). The authors conclude that glucose-6-phosphate dehydrogenase from L. mesenteroides is a reliable internal standard for radiation-inactivation studies of membrane preparations in the frozen state.

  12. Expression, crystallization and preliminary X-ray crystallographic analysis of glucose-6-phosphate dehydrogenase from the human pathogen Trypanosoma cruzi in complex with substrate

    PubMed Central

    Ortíz, Cecilia; Larrieux, Nicole; Medeiros, Andrea; Botti, Horacio; Comini, Marcelo; Buschiazzo, Alejandro

    2011-01-01

    An N-terminally truncated version of the enzyme glucose-6-phosphate dehydrogenase from Trypanosoma cruzi lacking the first 37 residues was crystallized both in its apo form and in a binary complex with glucose 6-­phosphate. The crystals both belonged to space group P21 and diffracted to 2.85 and 3.35 Å resolution, respectively. Self-rotation function maps were consistent with point group 222. The structure was solved by molecular replacement, confirming a tetrameric quaternary structure. PMID:22102256

  13. Neuroprotective effect of liquiritin as an antioxidant via an increase in glucose-6-phosphate dehydrogenase expression on B65 neuroblastoma cells.

    PubMed

    Nakatani, Yoshihiko; Kobe, Aya; Kuriya, Megumi; Hiroki, Yoko; Yahagi, Tadahiro; Sakakibara, Iwao; Matsuzaki, Keiichi; Amano, Taku

    2017-09-29

    Glycyrrhiza (the roots and rhizomes of licorice) has been used worldwide as both an herbal nutraceutical and herbal medicine. In addition, it is well known that Glycyrrhiza contains various compounds with biological effects, such as anti-viral, anti-inflammatory, immunoregulatory, anti-tumor and neuroprotective effects. Among the various compounds in Glycyrrhiza, the active compounds that show biological activity are thought to include glycyrrhizin, glycyrrhetinic acid, glabridin, licochalcones and liquiritin. In the present study, we investigated the biological effects of three of these compounds (glycyrrhizin, liquiritin and isoliquiritin) on B65 neuroblastoma cells derived from serotonergic neurons. Among these three compounds, only liquiritin enhanced the proliferation of B65 neuroblastoma cells. In contrast, both glycyrrhizin and isoliquiritin, particularly at high concentrations had cytotoxic effects. Cells were treated with various cytotoxic agents and liquiritin could ameliorate the cytotoxicity induced by menadione sodium bisulfate in a dose-dependent manner. We also examined the effect of liquiritin on cell survival by evaluating the expression levels of phospho-p44/42 mitogen-activated protein kinase, cyclin-related proteins and glucose-6-phosphate dehydrogenase, which produces nicotinamide adenine dinucleotide phosphate. Under treatment with liquiritin, the protein expression level of glucose-6-phosphate dehydrogenase increased in a dose-dependent manner. In contrast, the protein expression level of cyclin-related proteins did not change at all under treatment with liquiritin. These results suggest that liquiritin, which is contained in Glycyrrhiza, may enhance cell survival by increasing the protein expression level of glucose-6 phosphate dehydrogenase. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Unsuspected glucose-6-phosphate dehydrogenase deficiency presenting as symptomatic methemoglobinemia with severe hemolysis after fava bean ingestion in a 6-year-old boy.

    PubMed

    Odièvre, Marie-Hélène; Danékova, Névéna; Mesples, Bettina; Chemouny, Myriam; Couque, Nathalie; Parez, Nathalie; Ducrocq, Rolande; Elion, Jacques

    2011-05-01

    We report the occurrence of symptomatic methemoglobinemia in a previously healthy boy, who presented with severe acute hemolysis after fava bean ingestion. The methemoglobinemia revealed a previously unrecognized glucose-6-phosphate dehydrogenase (G6PD) deficiency. We discuss the pathophysiology of severe methemoglobinemia when associated with acute hemolysis, favism, and the common African G6PD A-variant [G6PD, VAL68MET, ASN126ASP]. In conclusion, screening for G6PD deficiency must be considered in symptomatic methemoglobinemia, especially in young boys, when associated with intravascular hemolysis.

  15. G6PD (Dublin): chronic non-spherocytic haemolytic anaemia resulting from glucose-6-phosphate dehydrogenase deficiency in an Irish kindred.

    PubMed Central

    McCann, S R; Smithwick, A M; Temperley, I J; Tipton, K

    1980-01-01

    A new variant of G6PD associated with chronic non-spherocytic haemolytic anaemia (CNSHA) in an Irish male is described. This variant is unique in that it has a normal electrophoretic mobility, Michaelis constant for G6P and NADP, and a normal pH optimum, together with a marked increase in utilisation of the substrate 2 deoxy glucose-6-phosphate. It is also relatively heat stable when compared with the normal (B) variant. These characteristics distinguish this variant from previously reported variants associated with CNSHA and we have called it G6PD Dublin. PMID:7401130

  16. pH-induced bistable dynamic behaviour in the reaction catalysed by glucose-6-phosphate dehydrogenase and conformational hysteresis of the enzyme.

    PubMed Central

    Aon, M A; Cortassa, S; Hervagault, J F; Thomas, D

    1989-01-01

    1. Bistable (multiple stationary states) dynamic behaviour in the activity of glucose-6-phosphate dehydrogenase that was subjected to successive pH change was demonstrated in an open continuously stirred tank reactor. Although the enzyme under study did not exhibit an autocatalytic effect and was homogeneously distributed, bistability was shown to occur. 2. The successive pH changes of the enzyme solution corresponded to a pH transition (8.3 in equilibrium 2), i.e. an acidification (forward direction) and an alkalinization (reverse direction). By use of intrinsic protein fluorescence methods, a glucose-6-phosphate dehydrogenase conformational hysteresis was shown to exist concomitant with the pH transition before and after enzyme injection into the reactor. 3. The results obtained suggest that the enzyme behaves, conformationally, as a memory device that stores information about its pH history (i.e. the enzyme records information in its structure about the environment to which it was previously exposed) and transduces it in a non-linear dynamic fashion, producing the bistable behaviour observed in the open reactor. PMID:2590166

  17. Cloning and characterization of an alternative transcript of ovine glucose 6-phosphate dehydrogenase gene: comparative approach between ruminant and non-ruminant species.

    PubMed

    Laliotis, George P; Argyrokastritis, Alexandros; Bizelis, Iosif; Rogdakis, Emmanuel

    2007-02-15

    Glucose 6-phosphate dehydrogenase (G6PD) plays an important role in ruminant's lipogenesis, as it provides necessary compounds of NADPH for the synthesis of fatty acids catalyzing the first committed reaction in the pentose phosphate pathway. In this work the full length ovine glucose 6-phosphate dehydrogenase cDNA was isolated using a polymerase chain reaction based strategy. Two isoforms (OG6PDA and OG6PDB) were detected encoding a protein of 515 and 524 amino acids, respectively. Both deduced amino acid sequences reveal a well conserved protein containing all the important residues for its catalytic role. The extra nine amino acids encoded by OG6PDB cause a frameshift in the polypeptide chain resulting in changes around the area of the potential substrate binding site. A three-dimensional model of ovine G6PD protein shows that this frameshift cause structural changes in the catalytic binding "pocket" of the molecule. Southern blot and RT analysis revealed that ovine G6PD appears as a single copy gene while it is expressed, with slight variability, in all tissues analyzed. Moreover, expression analysis of the ovine G6PD isoforms showed that OG6PDB is expressed only in tissues where lipogenesis is high in ruminants. Thus, we hypothesize that in ruminants G6PD may be regulated by the ratio of the two transcripts, according to the existence stimulus.

  18. Purification and characterization of glucose 6-phosphate dehydrogenase enzyme from rainbow trout (Oncorhynchus mykiss) liver and investigation of the effects of some metal ions on enzyme activity.

    PubMed

    Comakli, Veysel; Akkemik, Ebru; Ciftci, Mehmet; Kufrevioglu, Omer Irfan

    2015-05-01

    Glucose 6-phosphate dehydrogenase (d-glucose 6-phosphate: NADP(+) oxidoreductase, EC 1.1.1.49; G6PD) is a key enzyme that is localized in all mammal tissues, especially in cytoplasmic sections and that catalyzes the first step of pentose phosphate metabolic pathway. In this study, G6PD enzyme was purified 1444-fold with a yield of 77% from rainbow trout liver using 2',5'-ADP-sepharose-4B affinity chromatography. Moreover, a purity check of the enzyme was performed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Some characteristic features like optimal pH, stable pH, optimal temperature and optimal ionic strength were determined for the purified enzyme. In addition to this, in vitro effects of ions like silver nitrate (Ag(+)), thallium sulphate (TI(+)), cobalt (II) nitrate (Co(2+)) and arsenic (V) oxide (As(5+)) on enzyme activity were researched. Half-maximal inhibitory concentration (IC50) values of Ag(+), Co(2+) and As(5+) metal ions, which showed an inhibitory effect, were found to be 0.0044, 0.084 and 4.058 mM, respectively; and their inhibition constants (K i) were found to be 0.0052 ± 0.00042, 0.087 ± 0.015700 and 4.833 ± 1.753207 mM, respectively. Tl(+) not exhibited inhibitory effect on the enzyme activity. © The Author(s) 2013.

  19. Influence of glucose solution on the erythrocyte scattering properties

    NASA Astrophysics Data System (ADS)

    Naumenko, Elena K.

    2007-02-01

    The scattering characteristics of erythrocytes (the coefficients of extinction, scattering, absorption and indicatrixes) were calculated with using the theory Mie for spherical homogeneous spherical particles and the theory for two-layered spherical concentric particles. Transmission spectrums were measured with the spectrophotometer Cary500 in the wavelength range 460-860 n m. Specimens of liquid for imbedding of erythrocytes were preparing by mixing blood plasma a nd 50-% glucose solution with the different concentrations. The volume concentrations (hematocrit) of red blood cells (RBC) were maintained to have the same values in all specimens by adding equal volume of whole blood to immersion liquid of equal volumes. It has been shown that, contrary to theretical prediction, transmission is decreasing for all wavelengths with the addition of glucose solution in interval glucose volume concentrations 0.05 - 0.35-0.4. The subsequent increase of the glucose concentration leads to increasing of spectral transmission as a result of erythrocyte hemolysis.

  20. Microelectrode-based dielectric spectroscopy of glucose effect on erythrocytes.

    PubMed

    Colella, L; Beyer, C; Fröhlich, J; Talary, M; Renaud, P

    2012-06-01

    The dielectric response of biconcave erythrocytes exposed to D-glucose and L-glucose has been investigated using a double array of planar interdigitated microelectrodes on a glass microchip. Erythrocytes are analyzed under physiological conditions suspended in hypo-osmolar balanced solutions containing different glucose concentrations (0-20 mM). The glucose effect on the cellular dielectric properties is evaluated by analyzing the spectra using two different approaches, the equivalent circuit model and a modified model for ellipsoidal particles. The results show that at elevated glucose concentration (15 mM) the membrane capacitance increases by 36%, whereas the cytosol conductivity slightly decreases with a variation of about 15%. On the contrary, no variation has been registered with L-glucose, a biologically inactive enantiomer of D-glucose. The paper discusses the possible mechanism controlling the membrane dielectric response. As the external D-glucose increases, the number of activated glucose transporter in the erythrocyte membrane raises and the transition from sugar-free state to sugar-bounded state induces a change in the dipole moments and in the membrane capacitance.

  1. The Two Km's for ATP of Corn-Root H+-ATPase and the Use of Glucose-6-Phosphate and Hexokinase as an ATP-Regenerating System.

    PubMed Central

    Ramos, R. S.; Caldeira, M. T.; Arruda, P.; De Meis, L.

    1994-01-01

    Plasma membrane vesicles derived from corn (Zea mays L.) roots retain a membrane-bound H+-ATPase that is able to form a H+ gradient across the vesicle membranes. The activity of this ATPase is enhanced 2- to 3-fold when Triton X-100 or lysophosphatidylcholine is added to the medium at a protein:detergent ratio of 2:1 (w/w). In the absence of detergent, the ATPase exhibits only one Km for ATP (0.1-0.2 mM), which is the same as for the pumping of H+. After the addition of either Triton X-100 or lysophosphatidylcholine, two Km's for ATP are detected, one in the range of 1 to 3 [mu]M and a second in the range of 0.1 to 0.2 mM. The Vmax of the second Km for ATP increases as the temperature of the assay medium is raised from 15[deg]C to 38[deg]C. The Arrhenius plot reveals a single break at 30[deg]C, both in the absence and in the presence of detergents. In the presence of Triton X-100 the H+-ATPase catalyzes the cleavage of glucose-6-phosphate when both hexokinase and ADP are included in the assay medium. There is no measurable cleavage when the apparent affinity for ATP of the H+-ATPase is not enhanced by Triton X-100 or when 1 mM glucose is included in the assay medium. These data indicate that when the high-affinity Km for ATP is unmasked with the use of detergent, the ATPase can use glucose-6-phosphate and hexokinase as an ATP-regenerating system. PMID:12232248

  2. Discovery and characterization of an F420-dependent glucose-6-phosphate dehydrogenase (Rh-FGD1) from Rhodococcus jostii RHA1.

    PubMed

    Nguyen, Quoc-Thai; Trinco, Gianluca; Binda, Claudia; Mattevi, Andrea; Fraaije, Marco W

    2017-04-01

    Cofactor F420, a 5-deazaflavin involved in obligatory hydride transfer, is widely distributed among archaeal methanogens and actinomycetes. Owing to the low redox potential of the cofactor, F420-dependent enzymes play a pivotal role in central catabolic pathways and xenobiotic degradation processes in these organisms. A physiologically essential deazaflavoenzyme is the F420-dependent glucose-6-phosphate dehydrogenase (FGD), which catalyzes the reaction F420 + glucose-6-phosphate → F420H2 + 6-phospho-gluconolactone. Thereby, FGDs generate the reduced F420 cofactor required for numerous F420H2-dependent reductases, involved e.g., in the bioreductive activation of the antitubercular prodrugs pretomanid and delamanid. We report here the identification, production, and characterization of three FGDs from Rhodococcus jostii RHA1 (Rh-FGDs), being the first experimental evidence of F420-dependent enzymes in this bacterium. The crystal structure of Rh-FGD1 has also been determined at 1.5 Å resolution, showing a high similarity with FGD from Mycobacterium tuberculosis (Mtb) (Mtb-FGD1). The cofactor-binding pocket and active-site catalytic residues are largely conserved in Rh-FGD1 compared with Mtb-FGD1, except for an extremely flexible insertion region capping the active site at the C-terminal end of the TIM-barrel, which also markedly differs from other structurally related proteins. The role of the three positively charged residues (Lys197, Lys258, and Arg282) constituting the binding site of the substrate phosphate moiety was experimentally corroborated by means of mutagenesis study. The biochemical and structural data presented here provide the first step towards tailoring Rh-FGD1 into a more economical biocatalyst, e.g., an F420-dependent glucose dehydrogenase that requires a cheaper cosubstrate and can better match the demands for the growing applications of F420H2-dependent reductases in industry and bioremediation.

  3. Glucose-6-phosphate dehydrogenase Guadalajara--a case of chronic non-spherocytic haemolytic anaemia responding to splenectomy and the role of splenectomy in this disorder.

    PubMed

    Hamilton, J W; Jones, F G C; McMullin, Mary Frances

    2004-08-01

    Glucose-6-phosphate dehydrogenase (G6PD) is an enzyme of the pentose phosphate shunt pathway a major function of which is to prevent cellular oxidative damage. Deficiency in red blood cells is associated with a number of varied clinical manifestations. Chronic non-spherocytic haemolytic anaemia is uncommon but is usually characterized by chronic haemolysis, often with severe anaemia. In the past splenectomy in this condition has been thought to be of questionable benefit. We report a case of G6PD Guadalajara where splenectomy produced transfusion independence and have reviewed the literature. Those cases with exon 10 mutations often have a severe clinical phenotype, which responds to splenectomy. This procedure should be considered in this condition.

  4. Marked differences in drug-induced methemoglobinemia in sheep are not due to RBC glucose-6-phosphate dehydrogenase, reduced glutathione, or methemoglobin reductase activity

    SciTech Connect

    Martin, D.G.; Guertler, A.T.; Lagutchik, M.S.; Woodard, C.L.; Leonard, D.A.

    1993-05-13

    Benzocaine is a commonly used topical anesthetic that is structurally similar to current candidates for cyanide prophylaxis. Benzocaine induces profound methemoglobinemia in some sheep but not others. After topical benzocaine administration certain sheep respond to form MHb (elevated MHb 16-50% after a 56-280 mg dose, a 2-10 second spray with benzocine), while other phenotypically similar sheep fail to significantly form MHb (less than a 2% increase from baseline). Deficiencies in Glucose-6-phosphate dehydrogenase (G-6-PD), reduced glutathione (GSH), and MHb reductase increase the susceptibility to methemoglobinemia in man and animals. Sheep are used as a model for G-6-PD deficiency in man, and differences in this enzyme level could cause the variable response seen in these sheep. Similarly, differences in GSH and MHb reductase could be responsible for the observed differences in MHb formation.

  5. [Effect of aminotriazole on the activity of catalase and glucose-6-phosphate dehydrogenase in tissues of two frog species--Rana ridibunda and Rana esculenta].

    PubMed

    Lushchak, O V; Bahniukova, T V; Lushchak, V I

    2003-01-01

    Changes of the activity of catalase and glucose-6-phosphate dehydrogenase (G6PDH) during 48 hrs after intraperitoneal injection of 1.0, 0.5 and 0.1 mg aminotriazole per gram of body weight of two frog species as well as catalase inhibition by aminotriazole in vitro were investigated. Both aminotriazole concentration and species affiliation affected the catalase inhibition. The sensitivity of catalase from different tissues was decreased in the order: liver--kidney--lung--muscle--brain. The constant of half inhibition of lung catalase was significantly lower than that of liver and kidney catalase. The activity of G6PDH of AMT-treated frogs R. esculenta was higher comparing to control group. Possible ways of compensation of antioxidant defense under catalase inhibition are discussed.

  6. Prevalence of anemia, iron deficiency, thalassemia and glucose-6-phosphate dehydrogenase deficiency among hill-tribe school children in Omkoi District, Chiang Mai Province, Thailand.

    PubMed

    Yanola, Jintana; Kongpan, Chatpat; Pornprasert, Sakorn

    2014-07-01

    The prevalaence of anemia, iron deficiency, thalassemia and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency were examined among 265 hill-tribe school children, 8-14 years of age, from Omkoi District, Chiang Mai Province, Thailand. Anemia was observed in 20 school children, of whom 3 had iron deficiency anemia. The prevalence of G-6-PD deficiency and β-thalassemia trait [codon 17 (A>T), IVSI-nt1 (G>T) and codons 71/72 (+A) mutations] was 4% and 8%, respectively. There was one Hb E trait, and no α-thalassemia-1 SEA or Thai type deletion. Furthermore, anemia was found to be associated with β-thalassemia trait in 11 children. These data can be useful for providing appropriate prevention and control of anemia in this region of Thailand.

  7. A Novel de novo Mutation in the G6PD Gene in a Korean Boy with Glucose-6-phosphate Dehydrogenase Deficiency: Case Report.

    PubMed

    Jang, Mi-Ae; Kim, Ji-Yoon; Lee, Ki-O; Kim, Sun-Hee; Koo, Hong Hoe; Kim, Hee-Jin

    2015-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked recessive hemolytic anemia caused by a mutation in the G6PD gene on Xq28. Herein, we describe a Korean boy with G6PD deficiency resulting from a novel mutation in G6PD. A 20-month-old boy with hemolytic anemia was referred for molecular diagnosis. He had no relevant family history. The G6PD activity was severely decreased at 0.2 U/g Hb (severe deficiency). Direct sequencing analyses on the G6PD gene revealed that he was hemizygous for a novel missense variant, c.1187C>G (p.Pro396Arg), in exon 10 of G6PD. Family study involving his parents revealed the de novo occurrence of the mutation. This is the first report of genetically confirmed G6PD deficiency in Korea.

  8. [Frequency of color blindness and glucose-6-phosphate dehydrogenase enzyme deficiency in non-industrialized populations in the state of Nuevo León, México].

    PubMed

    Ceda-Flores, R M; Arriaga-Ríos, G; Muñoz-Campos, J; Bautista-Peña, V A; Angeles Rojas-Alvarado, M; González-Quiróga, G; Leal-Garza, C H; Garza-Chapa, R

    1990-01-01

    In order to know if there would be genetic structural differences among non industrial and industrial populations, two genetic markers were studied: color-blindness (CPC) and glucose-6-phosphate dehydrogenase deficiency (G6PD), in students, males and females that were resident in five non industrial populations in the State of Nuevo Leon. The results were compared with the information for industrial zone from the Monterrey Metropolitan area (AMM). It was found that the frequencies of CPC and G6PD in non industrial populations (2.57 and 0.00 per cent), were lower than the ones in the industrial AMM (4.0 and 0.66 per cent), probably as a result that in the first populations, with minor urbanization, the main factors that influence are: natural selection, interacial mixed or genetic drift and the second population is the immigration, since 1940 to present time, of Mexican populations with greater influence from the Indians and Africans.

  9. What is the true enzyme kinetics in the biological system? An investigation of macromolecular crowding effect upon enzyme kinetics of glucose-6-phosphate dehydrogenase.

    PubMed

    Norris, Matthew G S; Malys, Naglis

    2011-02-18

    Enzyme kinetic parameters for rate equations are vital in metabolic network simulation, a major part of systems biology research efforts. Measurements of Michaelis-Menten kinetic parameters Km and Kcat have been performed for enzymes glucose-6-phosphate dehydrogenase (G6P DH) under crowded conditions using molecular crowding agents bovine serum albumin (BSA) and polyethylene glycol (PEG) of 8000 Da molecular weight. An increase in Kcat was observed at very low concentrations of crowding agent, and also at high crowder concentrations when the experiment was performed at 45 °C with PEG. The observed pattern in Kcat for G6P DH at high crowder concentrations has been explained via modelling using excluded volume theory. An increase in rate was observed at 45 °C for G6P DH versus 30 °C; this has been modelled via the Arrhenius equation.

  10. Molecular Epidemiological Survey of Glucose-6-Phosphate Dehydrogenase Deficiency and Thalassemia in Uygur and Kazak Ethnic Groups in Xinjiang, Northwest China.

    PubMed

    Han, Luhao; Su, Hai; Wu, Hao; Jiang, Weiying; Chen, Suqin

    2016-06-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency and thalassemia occur frequently in tropical and subtropical regions, while the prevalence of relationship between the two diseases in Xinjiang has not been reported. We aimed to determine the prevalence of these diseases and clarify the relationship between genotypes and phenotypes of the two diseases in the Uygur and Kazak ethnic groups in Xinjiang. We measured G6PD activity by G6PD:6PGD (glucose acid-6-phosphate dehydrogenase) ratio, identified the gene variants of G6PD and α- and β-globin genes by polymerase chain reaction (PCR)-DNA sequencing and gap-PCR and compared these variants in different ethnic groups in Xinjiang with those adjacent to it. Of the 149 subjects with molecular analysis of G6PD deficiency conducted, a higher prevalence of the combined mutations c.1311C > T/IVSXI + 93T > C and IVSXI + 93T > C, both with normal enzymatic activities, were observed in the Uygur and Kazak subjects. A case of rare mutation HBB: c.135delC [codon 44 (-C) in the heterozygous state], a heterozygous case of HBB: c.68A > G [Hb G-Taipei or β22(B4)Glu→Gly] and several common single nucleotide polymorphisms (SNPs) were found on the β-globin gene. In conclusion, G6PD deficiency with pathogenic mutations and three common α-thalassemia (α-thal) [- -(SEA), -α(3.7) (rightward), -α(4.2) (leftward)] deletions and point mutations of the α-globin gene were not detected in the present study. The average incidence of β-thalassemia (β-thal) in Uygurs was 1.45% (2/138) in Xinjiang. The polymorphisms of G6PD and β-globin genes might be useful genetic markers to trace the origin and migration of the Uygur and Kazak in Xinjiang.

  11. Antisense inhibition of the plastidial glucose-6-phosphate/phosphate translocator in Vicia seeds shifts cellular differentiation and promotes protein storage.

    PubMed

    Rolletschek, Hardy; Nguyen, Thuy H; Häusler, Rainer E; Rutten, Twan; Göbel, Cornelia; Feussner, Ivo; Radchuk, Ruslana; Tewes, Annegret; Claus, Bernhard; Klukas, Christian; Linemann, Ute; Weber, Hans; Wobus, Ulrich; Borisjuk, Ljudmilla

    2007-08-01

    The glucose-6-phosphate/phosphate translocator (GPT) acts as an importer of carbon into the plastid. Despite the potential importance of GPT for storage in crop seeds, its regulatory role in biosynthetic pathways that are active during seed development is poorly understood. We have isolated GPT1 from Vicia narbonensis and studied its role in seed development using a transgenic approach based on the seed-specific legumin promoter LeB4. GPT1 is highly expressed in vegetative sink tissues, flowers and young seeds. In the embryo, localized upregulation of GPT1 at the onset of storage coincides with the onset of starch accumulation. Embryos of transgenic plants expressing antisense GPT1 showed a significant reduction (up to 55%) in the specific transport rate of glucose-6-phosphate as determined using proteoliposomes prepared from embryos. Furthermore, amyloplasts developed later and were smaller in size, while the expression of genes encoding plastid-specific translocators and proteins involved in starch biosynthesis was decreased. Metabolite analysis and stable isotope labelling demonstrated that starch biosynthesis was also reduced, although storage protein biosynthesis increased. This metabolic shift was characterized by upregulation of genes related to nitrogen uptake and protein storage, morphological variation of the protein-storing vacuoles, and a crude protein content of mature seeds of transgenics that was up to 30% higher than in wild-type. These findings provide evidence that (1) the prevailing level of GPT1 abundance/activity is rate-limiting for the synthesis of starch in developing seeds, (2) GPT1 exerts a controlling function on assimilate partitioning into storage protein, and (3) GPT1 is essential for the differentiation of embryonic plastids and seed maturation.

  12. In vivo effects of curcumin on the paraoxonase, carbonic anhydrase, glucose-6-phosphate dehydrogenase and β-glucosidase enzyme activities in dextran sulphate sodium-induced ulcerative colitis mice.

    PubMed

    Yildirim, Hatice; Sunay, Fatma Bahar; Sinan, Selma; Köçkar, Feray

    2016-12-01

    Increases in the risk of infections and malignancy due to immune suppressive therapies of inflammatory bowel diseases (IBDs) have led the researchers to focus on more nontoxic and acceptable natural products like curcumin. Here we investigate whether prophylactic and therapeutic application of the curcumin alters the enzyme activities of paraoxonase (PON), carbonic anhydrase (CA), glucose-6-phosphate dehydrogenase (G6PD) and cytosolic β-glucosidase in dextran sulphate sodium (DSS)-induced ulcerative colitis mice. Prophylactic application of curcumin resulted in higher MPO activity, less body weight loss and longer colon lengths compared to therapeutic group indicating preventive role of curcumin in IBDs. DSS-induced decrease in liver and serum PON activities were completely recovered by prophylactic administration of curcumin. DSS-induced reduction in liver cytosolic β-glucosidase activity was not affected by curcumin neither in the prophylactic group nor in the therapeutic group. Erythrocyte CA activity was significantly increased in curcumin groups, however no remarkable change in G6PD activity was observed.

  13. [Uptake of FDG (2-fluoro-2-deoxy-D-glucose) as a tumor imaging agent into erythrocytes and accumulation of FDG in tumor cells].

    PubMed

    Minosako, Yoshihito; Nemoto, Masahiro; Ino, Sento; Shirakami, Yoshifumi; Kurami, Miki

    2003-02-01

    Fluorine-18-2-fluoro-2-deoxy-D-glucose (18F-FDG) injectable was developed as a tumor imaging agent reflecting glucose metabolism. In membrane transportation studies, the uptake of 14C-FDG into erythrocytes decreased with an increase in glucose concentration, and Cytochalasin B, inhibitor of glucose transporter (GLUT), blocked the uptake about 75%. The results means FDG is transported into tumor cells mainly by GLUT as glucose analogues. 18F-FDG is recognized to be phosphorylated to 18F-FDG-6-phosphate with hexokinase. We found that FDG-6-phosphate was further isomerized to 18F-FDM-6-phosphate by phosphoglucose isomerase (PGI) in vitro. About 27% 18F-FDM-6-phosphate was generated at the reaction with 70 U PGI for 90 min. These results show that the 18F-FDG injectable manufactured by the commercial supply system has equivalent properties; membrane transportation characteristic and enzyme affinity, to FDG synthesized at each PET institution.

  14. Involvement of glucose-6-phosphate dehydrogenase in reduced glutathione maintenance and hydrogen peroxide signal under salt stress.

    PubMed

    Wang, Xiaomin; Ma, Yuanyuan; Huang, Chenghong; Li, Jisheng; Wan, Qi; Bi, Yurong

    2008-06-01

    Cellular redox homeostasis is essential for plant growth, development as well as for the resistance to biotic and abiotic stresses, which is governed by the complex network of prooxidant and antioxidant systems. Recently, new evidence has been published that NADPH, produced by glucose-6-phosephate dehydrogenase enzyme (G6PDH), not only acted as the reducing potential for the output of reduced glutathione (GSH), but was involved in the activity of plasma membrane (PM) NADPH oxidase under salt stress, which resulted in hydrogen peroxide (H(2)O(2)) accumulation. H(2)O(2) acts as a signal in regulating G6PDH activity and expression, and the activities of the enzymes in the glutathione cycle as well, through which the ability of GSH regeneration was increased under salt stress. Thus, G6PDH plays a critical role in maintaining cellular GSH levels under long-term salt stress. In this addendum, a hypothetical model for the roles of G6PDH in modulating the intracellular redox homeostasis under salt stress is presented.

  15. Molecular Characterization of Glucose-6-phosphate Dehydrogenase Deficiency in Families from the Republic of Macedonia and Genotype-phenotype Correlation

    PubMed Central

    Cherepnalkovski, Anet Papazovska; Zemunik, Tatijana; Glamocanin, Sofijanka; Piperkova, Katica; Gunjaca, Ivana; Kocheva, Svetlana; Jovanova, Biljana Coneska; Krzelj, Vjekoslav

    2015-01-01

    Introduction: Glucose-6-phospahte dehydrogenase deficiency (G6PD) is one of the most common inherited disorders affecting around 400 million people worldwide. Molecular analysis of the G6PD gene identified more than 140 distinct mutations, the majority being single base missense mutations. G6PD Mediterranean is the most common variant found in populations of the Mediterranean area. Aim: The aim of our study was to perform molecular characterization of G6PD deficiency in families from the Republic of Macedonia and correlate the findings to disease phenotype. Patients and methods: Six patients and seven other family members were selected for genetic characterization, the selection procedure involved clinical evaluation and G6PD quantitative testing. All patients were first screened for the Mediterranean mutation, and subsequently for the Seattle mutation. Mutations were detected using PCR amplification and appropriate restriction endonuclease cleavage. Results: Four hemizygote and 3 heterozygous carriers for G6PD Mediterranean were detected. All G6PD deficient patients from this group showed clinical picture of hemolysis, and in 66.6% neonatal jaundice was confirmed based on history data. To our knowledge, this is the first study concerned with molecular aspects of the G6PD deficiency in R. Macedonia. Conclusion: This study represents a step towards a more comprehensive genetic evaluation in our population and better understanding of the health issues involved. PMID:26622077

  16. Metabolomic profile of glycolysis and the pentose phosphate pathway identifies the central role of glucose-6-phosphate dehydrogenase in clear cell-renal cell carcinoma.

    PubMed

    Lucarelli, Giuseppe; Galleggiante, Vanessa; Rutigliano, Monica; Sanguedolce, Francesca; Cagiano, Simona; Bufo, Pantaleo; Lastilla, Gaetano; Maiorano, Eugenio; Ribatti, Domenico; Giglio, Andrea; Serino, Grazia; Vavallo, Antonio; Bettocchi, Carlo; Selvaggi, Francesco Paolo; Battaglia, Michele; Ditonno, Pasquale

    2015-05-30

    The analysis of cancer metabolome has shown that proliferating tumor cells require a large quantities of different nutrients in order to support their high rate of proliferation. In this study we analyzed the metabolic profile of glycolysis and the pentose phosphate pathway (PPP) in human clear cell-renal cell carcinoma (ccRCC) and evaluate the role of these pathways in sustaining cell proliferation, maintenance of NADPH levels, and production of reactive oxygen species (ROS). Metabolomic analysis showed a clear signature of increased glucose uptake and utilization in ccRCC tumor samples. Elevated levels of glucose-6-phosphate dehydrogenase (G6PDH) in association with higher levels of PPP-derived metabolites, suggested a prominent role of this pathway in RCC-associated metabolic alterations. G6PDH inhibition, caused a significant decrease in cancer cell survival, a decrease in NADPH levels, and an increased production of ROS, suggesting that the PPP plays an important role in the regulation of ccRCC redox homeostasis. Patients with high levels of glycolytic enzymes had reduced progression-free and cancer-specific survivals as compared to subjects with low levels. Our data suggest that oncogenic signaling pathways may promote ccRCC through rerouting the sugar metabolism. Blocking the flux through this pathway may serve as a novel therapeutic target.

  17. Enhanced production of epsilon-caprolactone by overexpression of NADPH-regenerating glucose 6-phosphate dehydrogenase in recombinant Escherichia coli harboring cyclohexanone monooxygenase gene.

    PubMed

    Lee, Won-Heong; Park, Jin-Byung; Park, Kyungmoon; Kim, Myoung-Dong; Seo, Jin-Ho

    2007-08-01

    Whole-cell conversion of cyclohexanone to epsilon-caprolactone was attempted by recombinant Escherichia coli BL21(DE3) expressing cyclohexanone monooxygenase (CHMO) of Acinetobacter calcoaceticus NCIMB 9871. High concentrations of cyclohexanone and epsilon-caprolactone reduced CHMO-mediated bioconversion of cyclohexanone to epsilon-caprolactone in the resting recombinant E. coli cells. Metabolically active cells were employed by adopting a fed-batch culture to improve the production of epsilon-caprolactone from cyclohexanone. A glucose-limited fed-batch Baeyer-Villiger oxidation where a cyclohexanone level was maintained less than 6 g/l resulted in a maximum epsilon-caprolactone concentration of 11.0 g/l. The maximum epsilon-caprolactone concentration was improved further to 15.3 g/l by coexpression of glucose-6-phosphate dehydrogenase, an NADPH-generating enzyme encoded by the zwf gene which corresponded to a 39% enhancement in epsilon-caprolactone concentration compared with the control experiment performed under the same conditions.

  18. Metabolomic profile of glycolysis and the pentose phosphate pathway identifies the central role of glucose-6-phosphate dehydrogenase in clear cell-renal cell carcinoma

    PubMed Central

    Sanguedolce, Francesca; Cagiano, Simona; Bufo, Pantaleo; Lastilla, Gaetano; Maiorano, Eugenio; Ribatti, Domenico; Giglio, Andrea; Serino, Grazia; Vavallo, Antonio; Bettocchi, Carlo; Selvaggi, Francesco Paolo; Battaglia, Michele; Ditonno, Pasquale

    2015-01-01

    The analysis of cancer metabolome has shown that proliferating tumor cells require a large quantities of different nutrients in order to support their high rate of proliferation. In this study we analyzed the metabolic profile of glycolysis and the pentose phosphate pathway (PPP) in human clear cell-renal cell carcinoma (ccRCC) and evaluate the role of these pathways in sustaining cell proliferation, maintenance of NADPH levels, and production of reactive oxygen species (ROS). Metabolomic analysis showed a clear signature of increased glucose uptake and utilization in ccRCC tumor samples. Elevated levels of glucose-6-phosphate dehydrogenase (G6PDH) in association with higher levels of PPP-derived metabolites, suggested a prominent role of this pathway in RCC-associated metabolic alterations. G6PDH inhibition, caused a significant decrease in cancer cell survival, a decrease in NADPH levels, and an increased production of ROS, suggesting that the PPP plays an important role in the regulation of ccRCC redox homeostasis. Patients with high levels of glycolytic enzymes had reduced progression-free and cancer-specific survivals as compared to subjects with low levels. Our data suggest that oncogenic signaling pathways may promote ccRCC through rerouting the sugar metabolism. Blocking the flux through this pathway may serve as a novel therapeutic target. PMID:25945836

  19. Glucose-6-phosphate isomerase deficiency results in mTOR activation, failed translocation of lipin 1α to the nucleus and hypersensitivity to glucose: Implications for the inherited glycolytic disease.

    PubMed

    Haller, Jorge F; Krawczyk, Sarah A; Gostilovitch, Lubov; Corkey, Barbara E; Zoeller, Raphael A

    2011-11-01

    Inherited glucose-6-phosphate isomerase (GPI) deficiency is the second most frequent glycolytic erythroenzymopathy in humans. Patients present with non-spherocytic anemia of variable severity and with neuromuscular dysfunction. We previously described Chinese hamster (CHO) cell lines with mutations in GPI and loss of GPI activity. This resulted in a temperature sensitivity and severe reduction in the synthesis of glycerolipids due to a reduction in phosphatidate phosphatase (PAP). In the current article we attempt to describe the nature of this pleiotropic effect. We cloned and sequenced the CHO lipin 1 cDNA, a gene that codes for PAP activity. Overexpression of lipin 1 in the GPI-deficient cell line, GroD1 resulted in increased PAP activity, however it failed to restore glycerolipid biosynthesis. Fluorescence microscopy showed a failure of GPI-deficient cells to localize lipin 1α to the nucleus. We also found that glucose-6-phosphate levels in GroD1 cells were 10-fold over normal. Lowering glucose levels in the growth medium partially restored glycerolipid biosynthesis and nuclear localization of lipin 1α. Western blot analysis of the elements within the mTOR pathway, which influences lipin 1 activity, was consistent with an abnormal activation of this system. Combined, these data suggest that GPI deficiency results in an accumulation of glucose-6-phosphate, and possibly other glucose-derived metabolites, leading to activation of mTOR and sequestration of lipin 1 to the cytosol, preventing its proper functioning. These results shed light on the mechanism underlying the pathologies associated with inherited GPI deficiency and the variability in the severity of the symptoms observed in these patients.

  20. Expression of escherichia coli otsA in a Saccharomyces cerevisiae tps1 mutant restores trehalose 6-phosphate levels and partly restores growth and fermentation with glucose and control of glucose influx into glycolysis.

    PubMed

    Bonini, B M; Van Vaeck, C; Larsson, C; Gustafsson, L; Ma, P; Winderickx, J; Van Dijck, P; Thevelein, J M

    2000-08-15

    The TPS1 gene, encoding trehalose-6-phosphate synthase (TPS), exerts an essential control on the influx of glucose into glycolysis in the yeast Saccharomyces cerevisiae. The deletion of TPS1 causes an inability to grow on glucose because of a hyperaccumulation of sugar phosphates and depletion of ATP and phosphate. We show that expression of the Escherichia coli homologue, otsA, in a yeast tps1 mutant results in high TPS activity. Although the trehalose 6-phosphate (Tre6P) level during exponential growth on glucose was at least as high as in a wild-type yeast strain, growth on glucose was only partly restored and the lag phase was much longer. Measurement of the glycolytic metabolites immediately after the addition of glucose showed that in spite of a normal Tre6P accumulation there was still a partial hyperaccumulation of sugar phosphates. Strong elevation of the Tre6P level by the additional deletion of the TPS2 gene, which encodes Tre6P phosphatase, was not able to cause a strong decrease in the sugar phosphate levels in comparison with the wild-type strain. In addition, in chemostat experiments the short-term response to a glucose pulse was delayed, but normal metabolism was regained over a longer period. These results show that Tre6P synthesis from a heterologous TPS enzyme can to some extent restore the control of glucose influx into glycolysis and growth on glucose in yeast. However, they also indicate that the yeast TPS enzyme, as opposed to the E. coli otsA gene product, is able to increase the efficiency of the Tre6P control on glucose influx into yeast glycolysis.

  1. The chemopreventive properties of chlorogenic acid reveal a potential new role for the microsomal glucose-6-phosphate translocase in brain tumor progression

    PubMed Central

    Belkaid, Anissa; Currie, Jean-Christophe; Desgagnés, Julie; Annabi, Borhane

    2006-01-01

    Background Chlorogenic acid (CHL), the most potent functional inhibitor of the microsomal glucose-6-phosphate translocase (G6PT), is thought to possess cancer chemopreventive properties. It is not known, however, whether any G6PT functions are involved in tumorigenesis. We investigated the effects of CHL and the potential role of G6PT in regulating the invasive phenotype of brain tumor-derived glioma cells. Results RT-PCR was used to show that, among the adult and pediatric brain tumor-derived cells tested, U-87 glioma cells expressed the highest levels of G6PT mRNA. U-87 cells lacked the microsomal catalytic subunit glucose-6-phosphatase (G6Pase)-α but expressed G6Pase-β which, when coupled to G6PT, allows G6P hydrolysis into glucose to occur in non-glyconeogenic tissues such as brain. CHL inhibited U-87 cell migration and matrix metalloproteinase (MMP)-2 secretion, two prerequisites for tumor cell invasion. Moreover, CHL also inhibited cell migration induced by sphingosine-1-phosphate (S1P), a potent mitogen for glioblastoma multiform cells, as well as the rapid, S1P-induced extracellular signal-regulated protein kinase phosphorylation potentially mediated through intracellular calcium mobilization, suggesting that G6PT may also perform crucial functions in regulating intracellular signalling. Overexpression of the recombinant G6PT protein induced U-87 glioma cell migration that was, in turn, antagonized by CHL. MMP-2 secretion was also inhibited by the adenosine triphosphate (ATP)-depleting agents 2-deoxyglucose and 5-thioglucose, a mechanism that may inhibit ATP-mediated calcium sequestration by G6PT. Conclusion We illustrate a new G6PT function in glioma cells that could regulate the intracellular signalling and invasive phenotype of brain tumor cells, and that can be targeted by the anticancer properties of CHL. PMID:16566826

  2. Glucose-6-phosphate dehydrogenase deficiency

    MedlinePlus

    ... be available to those who have a family history of the condition. Alternative Names ... PG. Hemolytic anemias. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap ...

  3. Glucose-6-phosphate dehydrogenase plays a central role in the response of tomato (Solanum lycopersicum) plants to short and long-term drought.

    PubMed

    Landi, Simone; Nurcato, Roberta; De Lillo, Alessia; Lentini, Marco; Grillo, Stefania; Esposito, Sergio

    2016-08-01

    The present study was undertaken to investigate the expression, occurrence and activity of glucose 6 phosphate dehydrogenase (G6PDH - EC 1.1.1.49), the key-enzyme of the Oxidative Pentose Phosphate Pathway (OPPP), in tomato plants (Solanum lycopersicum cv. Red Setter) exposed to short- and long-term drought stress. For the first time, drought effects have been evaluated in plants under different growth conditions: in hydroponic laboratory system, and in greenhouse pots under controlled conditions; and in open field, in order to evaluate drought response in a representative agricultural environment. Interestingly, changes observed appear strictly associated to the induction of well known stress response mechanisms, such as the increase of proline synthesis, accumulation of chaperone Hsp70, and ascorbate peroxidase. Results show significant increase in total activity of G6PDH, and specifically in expression and occurrence of cytosolic isoform (cy-G6PDH) in plants grown in any cultivation system upon drought. Intriguingly, the results clearly suggest that abscissic acid (ABA) pathway and signaling cascade (protein phosphatase 2C PP2C) could be strictly related to increased G6PDH expression, occurrence and activities. We hypothesized for G6PDH a specific role as one of the main reductants' suppliers to counteract the effects of drought stress, in the light of converging evidences given by young and adult tomato plants under stress of different duration and intensity.

  4. Avoiding Buffer Interference in ITC Experiments: A Case Study from the Analysis of Entropy-Driven Reactions of Glucose-6-Phosphate Dehydrogenase.

    PubMed

    Bianconi, M Lucia

    2016-01-01

    Isothermal titration calorimetry (ITC) is a label-free technique that allows the direct determination of the heat absorbed or released in a reaction. Frequently used to determining binding parameters in biomolecular interactions, it is very useful to address enzyme-catalyzed reactions as both kinetic and thermodynamic parameters can be obtained. Since calorimetry measures the total heat effects of a reaction, it is important to consider the contribution of the heat of protonation/deprotonation that is possibly taking place. Here, we show a case study of the reaction catalyzed by the glucose-6-phosphate dehydrogenase (G6PD) from Leuconostoc mesenteroides. This enzyme is able to use either NAD(+) or NADP(+) as a cofactor. The reactions were done in five buffers of different enthalpy of protonation. Depending on the buffer used, the observed calorimetric enthalpy (ΔH(cal)) of the reaction varied from -22.93 kJ/mol (Tris) to 19.37 kJ/mol (phosphate) for the NADP(+)-linked reaction, and -11.67 kJ/mol (Tris) to 7.32 kcal/mol or 30.63 kJ/mol (phosphate) for the NAD(+) reaction. We will use this system as an example of how to extract proton-independent reaction enthalpies from kinetic data to ensure that the reported accurately represent the intrinsic heat of reaction.

  5. Increased red cell calcium, decreased calcium adenosine triphosphatase, and altered membrane proteins during fava bean hemolysis in glucose-6-phosphate dehydrogenase-deficient (Mediterranean variant) individuals.

    PubMed

    Turrini, F; Naitana, A; Mannuzzu, L; Pescarmona, G; Arese, P

    1985-08-01

    RBCs from four glucose-6-phosphate dehydrogenase (G6PD)-deficient (Mediterranean variant) subjects were studied during fava bean hemolysis. In the density-fractionated RBC calcium level, Ca2+-ATPase activity, reduced glutathione level, and ghost protein pattern were studied. In the bottom fraction, containing most heavily damaged RBCs, calcium level ranged from 143 to 244 mumol/L RBCs (healthy G6PD-deficient controls: 17 +/- 5 mumol/L RBCs). The Ca2+-ATPase activity ranged from 0.87 to 1.84 mumol ATP consumed/g Hb/min (healthy G6PD-deficient controls: 2.27 +/- 0.4). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of ghosts showed: (1) the presence of high mol wt aggregates (in three cases they were reduced by dithioerythritol; in one case, only partial reduction was possible); (2) the presence of multiple, scattered new bands; and (3) the reduction of band 3. Oxidant-mediated damage to active calcium extrusion, hypothetically associated with increased calcium permeability, may explain the large increase in calcium levels. They, in turn, could activate calcium-dependent protease activity, giving rise to the profound changes in the ghost protein pattern.

  6. Mutations of Glucose-6-Phosphate Dehydrogenase Durham, Santa-Maria and A+ Variants Are Associated with Loss Functional and Structural Stability of the Protein.

    PubMed

    Gómez-Manzo, Saúl; Marcial-Quino, Jaime; Vanoye-Carlo, America; Enríquez-Flores, Sergio; De la Mora-De la Mora, Ignacio; González-Valdez, Abigail; García-Torres, Itzhel; Martínez-Rosas, Víctor; Sierra-Palacios, Edgar; Lazcano-Pérez, Fernando; Rodríguez-Bustamante, Eduardo; Arreguin-Espinosa, Roberto

    2015-12-02

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymopathy in the world. More than 160 mutations causing the disease have been identified, but only 10% of these variants have been studied at biochemical and biophysical levels. In this study we report on the functional and structural characterization of three naturally occurring variants corresponding to different classes of disease severity: Class I G6PD Durham, Class II G6PD Santa Maria, and Class III G6PD A+. The results showed that the G6PD Durham (severe deficiency), and the G6PD Santa Maria and A+ (less severe deficiency) (Class I, II and III, respectively) affect the catalytic efficiency of these enzymes, are more sensitive to temperature denaturing, and affect the stability of the overall protein when compared to the wild type WT-G6PD. In the variants, the exposure of more and buried hydrophobic pockets was induced and monitored with 8-Anilinonaphthalene-1-sulfonic acid (ANS) fluorescence, directly affecting the compaction of structure at different levels and probably reducing the stability of the protein. The degree of functional and structural perturbation by each variant correlates with the clinical severity reported in different patients.

  7. The use of primaquine in malaria infected patients with red cell glucose-6-phosphate dehydrogenase (G6PD) deficiency in Myanmar.

    PubMed

    Myat-Phone-Kyaw; Myint-Oo; Aung-Naing; Aye-Lwin-Htwe

    1994-12-01

    32 subjects with Plasmodium falciparum gametocytes, and 31 cases with Plasmodium vivax infection from two military hospitals (Lashio, Mandalay) were treated with quinine 600 mg three times a day for 7 days followed by primaquine 45 mg single dose for gametocytes and 45 mg weekly x 8 weeks for vivax malaria. Although screening of red cell glucose-6-phosphate dehydrogenase (G6PD) was done prior to primaquine treatment, G6PD deficient subjects were not excluded from the trial. 20 patients hemizygous for mild G6PD deficiency (GdB- variant), 2 patients hemizygous for severe deficiency (Gd-Myanmar variant) completed the trial. No case of acute hemolysis was observed in all 22 patients with two genotypes of red cell G6PD deficiency status. Therefore, a single dose of primaquine 45 mg and/or weekly for 8 weeks is adequate for the treatment of patients with P. falciparum gametocytes and/or P. vivax malaria ignoring these red cell G6PD enzyme deficient variants in Myanmar.

  8. Increased activity of 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenase in purified cell suspensions and single cells from the uterine cervix in cervical intraepithelial neoplasia.

    PubMed Central

    Jonas, S. K.; Benedetto, C.; Flatman, A.; Hammond, R. H.; Micheletti, L.; Riley, C.; Riley, P. A.; Spargo, D. J.; Zonca, M.; Slater, T. F.

    1992-01-01

    The activities of 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenase have been measured in squamous epithelial cells of the uterine cervix from normal patients and cases of cervical intraepithelial neoplasia (CIN). A biochemical cycling method, which uses only simple equipment and is suited to routine use and to automation, was applied to cells separated by gradient centrifugation. In addition, cells were examined cytochemically, and the intensity of staining in the cytoplasm of single whole cells was measured using computerised microcytospectrophotometry. Twenty per cent of cells in samples from normal patients (n=61) showed staining intensities above an extinction of 0.15 at 540 nm, compared to 71% of cases of CIN 1 (n=14), 91% of cases of CIN 2 (n=11) and 67% of cases of CIN 3 (n=15). The cytochemical data do not allow definitive distinctions to be made between different grades of CIN whereas the biochemical assay applied to cell lysates shows convincing differences between normal samples and cases of CIN. There are no false negatives for CIN 3 (n=14) and CIN 2 (n=10) and 11% false negatives for CIN 1 (n=9) and 14% of false positives for normal cases (n=21). The results of this preliminary study with reference to automation are discussed [corrected]. Images Figure 1 PMID:1637668

  9. Exposure to chrysotile asbestos causes carbonylation of glucose 6-phosphate dehydrogenase through a reaction with lipid peroxidation products in human lung epithelial cells.

    PubMed

    Ogasawara, Yuki; Ishii, Kazuyuki

    2010-05-19

    Exposure to asbestos is known to lead to a reduction in glucose 6-phosphate dehydrogenase (G6PDH) activity and to cause oxidative damage to cells. In the present study, we exposed the human lung carcinoma cell line A549 to chrysotile. We observed an increase in the production of thiobarbituric acid-reactive substances (TBARS, the breakdown products of lipid peroxide) along with a significant decrease in G6PDH activity. Alternatively, when chrysotile was added directly to the cell extract obtained by removing the cell membrane, no loss of G6PDH activity was observed. To elucidate the mechanism of G6PDH inactivation due to exposure to chrysotile, we focused on the TBARS responsible for protein modification via carbonylation. When malondialdehyde or 4-hydroxy-2-nonenal was added to a membrane-free A549 cell extract, G6PDH activity was reduced markedly. However, when t-butylhydroperoxide was added to the extract, there was no significant decrease in G6PDH activity. Western blot analysis and immunoprecipitation of the carbonylated proteins in the A549 cell lysate that was prepared after exposure to chrysotile demonstrated that G6PDH had been carbonylated. Our findings indicate that the decrease in G6PDH activity that occurs after exposure of the cultured cells to chrysotile results from the carbonylation of G6PDH by TBARS.

  10. DNA damage and apoptosis in mononuclear cells from glucose-6-phosphate dehydrogenase-deficient patients (G6PD Aachen variant) after UV irradiation.

    PubMed

    Efferth, T; Fabry, U; Osieka, R

    2001-03-01

    Patients affected with X chromosome-linked, hereditary glucose-6-phosphate dehydrogenase (G6PD) deficiency suffer from life-threatening hemolytic crises after intake of certain drugs or foods. G6PD deficiency is associated with low levels of reduced glutathione. We analyzed mononuclear white blood cells (MNC) of three males suffering from the German G6PD Aachen variant, four heterozygote females of this family, one G6PD-deficient male from another family coming from Iran, and six healthy male volunteers with respect to their DNA damage in two different genes (G6PD and T-cell receptor-delta) and their propensity to enter apoptosis after UV illumination (0.08-5.28 J/cm2). As determined by PCR stop assays, there was more UV-induced DNA damage in MNC of G6PD-deficient male patients than in those of healthy subjects. MNC of G6PD-deficient patients showed a higher rate of apoptosis after UV irradiation than MNC of healthy donors. MNC of heterozygote females showed intermediate rates of DNA damage and apoptosis. It is concluded that increased DNA damage may be a result of deficient detoxification of reactive oxygen species by glutathione and may ultimately account for the higher rate of apoptosis in G6PD-deficient MNC.

  11. Effects of dehydroepiandrosterone on obesity and glucose-6-phosphate dehydrogenase activity in the lethal yellow mouse (strain 129/Sv-Ay/Aw).

    PubMed

    Granholm, N H; Staber, L D; Wilkin, P J

    1987-04-01

    We investigated the anti-obesity effects of the adrenal androgen, dehydroepiandrosterone (DHEA), on genetically predisposed obese lethal yellow mice (Ay/Aw). Secondly, we tested the hypothesis that DHEA promotes its anti-obesity effects by decreasing the activity of glucose-6-phosphate dehydrogenase (G6PDH). We subjected four genotype-sex combinations of yellow and agouti (control) mice to four dietary treatments and determined weight changes, food consumption, and G6PDH activity. Although G6PDH activities of yellow mice were considerably decreased in the 0.4% DHEA treatment group, they were elevated in the 0.0 and 0.1% DHEA treatment groups. In contrast, G6PDH activities of DHEA-treated control agouti mice remained relatively constant. These studies confirm that DHEA prevents the Ay gene from promoting excess fat deposition via some mechanism(s) other than reduced dietary intake. However, the overall absence of agreement between weight change (gain or loss) and G6PDH activity suggests that the anti-obesity activity of DHEA is not mediated via G6PDH. Since yellow obese (Ay/Aw) mice were found to be more susceptible to DHEA's effects than their agouti (Aw/Aw) littermates, Ay appears to induce an altered metabolism in Ay/Aw mice which is more susceptible to the effects of DHEA than the normal metabolism of Aw/Aw mice.

  12. Somatic-cell selection is a major determinant of the blood-cell phenotype in heterozygotes for glucose-6-phosphate dehydrogenase mutations causing severe enzyme deficiency.

    PubMed Central

    Filosa, S.; Giacometti, N.; Wangwei, C.; De Mattia, D.; Pagnini, D.; Alfinito, F.; Schettini, F.; Luzzatto, L.; Martini, G.

    1996-01-01

    X-chromosome inactivation in mammals is regarded as an essentially random process, but the resulting somatic-cell mosaicism creates the opportunity for cell selection. In most people with red-blood-cell glucose-6-phosphate dehydrogenase (G6PD) deficiency, the enzyme-deficient phenotype is only moderately expressed in nucleated cells. However, in a small subset of hemizygous males who suffer from chronic nonspherocytic hemolytic anemia, the underlying mutations (designated class I) cause more-severe G6PD deficiency, and this might provide an opportunity for selection in heterozygous females during development. In order to test this possibility we have analyzed four heterozygotes for class I G6PD mutations: two with G6PD Portici (1178G-->A) and two with G6PD Bari (1187C-->T). We found that in fractionated blood cell types (including erythroid, myeloid, and lymphoid cell lineages) there was a significant excess of G6PD-normal cells. The significant concordance that we have observed in the degree of imbalance in the different blood-cell lineages indicates that a selective mechanism is likely to operate at the level of pluripotent blood stem cells. Thus, it appears that severe G6PD deficiency affects adversely the proliferation or the survival of nucleated blood cells and that this phenotypic characteristic is critical during hematopoiesis. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8808605

  13. Magnetic resonance angiography-defined intracranial vasculopathy is associated with silent cerebral infarcts and glucose-6-phosphate dehydrogenase mutation in children with sickle cell anaemia.

    PubMed

    Thangarajh, Mathula; Yang, Genyan; Fuchs, Dana; Ponisio, Maria R; McKinstry, Robert C; Jaju, Alok; Noetzel, Michael J; Casella, James F; Barron-Casella, Emily; Hooper, W Craig; Boulet, Sheree L; Bean, Christopher J; Pyle, Meredith E; Payne, Amanda B; Driggers, Jennifer; Trau, Heidi A; Vendt, Bruce A; Rodeghier, Mark; DeBaun, Michael R

    2012-11-01

    Silent cerebral infarct (SCI) is the most commonly recognized cause of neurological injury in sickle cell anaemia (SCA). We tested the hypothesis that magnetic resonance angiography (MRA)-defined vasculopathy is associated with SCI. Furthermore, we examined genetic variations in glucose-6-phosphate dehydrogenase (G6PD) and HBA (α-globin) genes to determine their association with intracranial vasculopathy in children with SCA. Magnetic resonance imaging (MRI) of the brain and MRA of the cerebral vasculature were available in 516 paediatric patients with SCA, enrolled in the Silent Infarct Transfusion (SIT) Trial. All patients were screened for G6PD mutations and HBA deletions. SCI were present in 41·5% (214 of 516) of SIT Trial children. The frequency of intracranial vasculopathy with and without SCI was 15·9% and 6·3%, respectively (P < 0·001). Using a multivariable logistic regression model, only the presence of a SCI was associated with increased odds of vasculopathy (P = 0·0007, odds ratio (OR) 2·84; 95% Confidence Interval (CI) = 1·55-5·21). Among male children with SCA, G6PD status was associated with vasculopathy (P = 0·04, OR 2·78; 95% CI = 1·04-7·42), while no significant association was noted for HBA deletions. Intracranial vasculopathy was observed in a minority of children with SCA, and when present, was associated with G6PD status in males and SCI.

  14. Rapid epidemiologic assessment of glucose-6-phosphate dehydrogenase deficiency in malaria-endemic areas in Southeast Asia using a novel diagnostic kit.

    PubMed

    Jalloh, A; Tantular, I S; Pusarawati, S; Kawilarang, A P; Kerong, H; Lin, K; Ferreira, M U; Matsuoka, H; Arai, M; Kita, K; Kawamoto, F

    2004-05-01

    We recently reported a new rapid screening method for glucose-6-phosphate dehydrogenase (G6PD) deficiency. This method incorporates a new formazan substrate (WST-8) and is capable of detecting heterozygous females both qualitatively and quantitatively. Here, we report its evaluation during field surveys at three malaria centres and in malaria-endemic villages of Myanmar and Indonesia, either alone or in combination with a rapid on-site diagnosis of malaria. A total of 57 severe (45 males and 12 females) and 34 mild (five males and 29 females) cases of G6PD deficiency were detected among 855 subjects in Myanmar whilst 30 severe (25 males and five females) and 23 mild (six males and 17 females) cases were found among 1286 subjects in Indonesia. In all cases, severe deficiency was confirmed with another formazan method but due to limitations in its detection threshold, mild cases were misdiagnosed as G6PD-normal by this latter method. Our results indicate that the novel method can qualitatively detect both severely deficient subjects as well as heterozygous females in the field. The antimalarial drug, primaquine, was safely prescribed to Plasmodium vivax-infected patients in Myanmar. Our new, rapid screening method may be essential for the diagnosis of G6PD deficiency particularly in rural areas without electricity, and can be recommended for use in malaria control programmes.

  15. Somatic-cell selection is a major determinant of the blood-cell phenotype in heterozygotes for glucose-6-phosphate dehydrogenase mutations causing severe enzyme deficiency

    SciTech Connect

    Filosa, S.; Giacometti, N.; Wangwei, C.; Martini, G.

    1996-10-01

    X-chromosome inactivation in mammals is regarded as an essentially random process, but the resulting somatic-cell mosaicism creates the opportunity for cell selection. In most people with red-blood-cell glucose-6-phosphate dehydrogenase (G6PD) deficiency, the enzyme-deficient phenotype is only moderately expressed in nucleated cells. However, in a small subset of hemizygous males who suffer from chronic nonspherocytic hemolytic anemia, the underlying mutations (designated class I) cause more-severe G6PD deficiency, and this might provide an opportunity for selection in heterozygous females during development. In order to test this possibility we have analyzed four heterozygotes for class I G6PD mutations: two with G6PD Portici (1178G{r_arrow}A) and two with G6PD Bari (1187C{r_arrow}T). We found that in fractionated blood cell types (including erythroid, myeloid, and lymphoid cell lineages) there was a significant excess of G6PD-normal cells. The significant concordance that we have observed in the degree of imbalance in the different blood-cell lineages indicates that a selective mechanism is likely to operate at the level of pluripotent blood stem cells. Thus, it appears that severe G6PD deficiency affects adversely the proliferation or the survival of nucleated blood cells and that this phenotypic characteristic is critical during hematopoiesis. 65 refs., 6 figs., 3 tabs.

  16. Overcompensation in Response to Herbivory in Arabidopsis thaliana: The Role of Glucose-6-Phosphate Dehydrogenase and the Oxidative Pentose-Phosphate Pathway

    PubMed Central

    Siddappaji, Madhura H.; Scholes, Daniel R.; Bohn, Martin; Paige, Ken N.

    2013-01-01

    That some plants benefit from being eaten is counterintuitive, yet there is now considerable evidence demonstrating enhanced fitness following herbivory (i.e., plants can overcompensate). Although there is evidence that genetic variation for compensation exists, little is known about the genetic mechanisms leading to enhanced growth and reproduction following herbivory. We took advantage of the compensatory variation in recombinant inbred lines of Arabidopsis thaliana, combined with microarray and QTL analyses to assess the molecular basis of overcompensation. We found three QTL explaining 11.4, 10.1, and 26.7% of the variation in fitness compensation, respectively, and 109 differentially expressed genes between clipped and unclipped plants of the overcompensating ecotype Columbia. From the QTL/microarray screen we uncovered one gene that plays a significant role in overcompensation: glucose-6-phosphate-1-dehydrogenase (G6PDH1). Knockout studies of Transfer-DNA (T-DNA) insertion lines and complementation studies of G6PDH1 verify its role in compensation. G6PDH1 is a key enzyme in the oxidative pentose-phosphate pathway that plays a central role in plant metabolism. We propose that plants capable of overcompensating reprogram their transcriptional activity by up-regulating defensive genes and genes involved in energy metabolism and by increasing DNA content (via endoreduplication) with the increase in DNA content feeding back on pathways involved in defense and metabolism through increased gene expression. PMID:23934891

  17. Mutations of Glucose-6-Phosphate Dehydrogenase Durham, Santa-Maria and A+ Variants Are Associated with Loss Functional and Structural Stability of the Protein

    PubMed Central

    Gómez-Manzo, Saúl; Marcial-Quino, Jaime; Vanoye-Carlo, America; Enríquez-Flores, Sergio; De la Mora-De la Mora, Ignacio; González-Valdez, Abigail; García-Torres, Itzhel; Martínez-Rosas, Víctor; Sierra-Palacios, Edgar; Lazcano-Pérez, Fernando; Rodríguez-Bustamante, Eduardo; Arreguin-Espinosa, Roberto

    2015-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymopathy in the world. More than 160 mutations causing the disease have been identified, but only 10% of these variants have been studied at biochemical and biophysical levels. In this study we report on the functional and structural characterization of three naturally occurring variants corresponding to different classes of disease severity: Class I G6PD Durham, Class II G6PD Santa Maria, and Class III G6PD A+. The results showed that the G6PD Durham (severe deficiency), and the G6PD Santa Maria and A+ (less severe deficiency) (Class I, II and III, respectively) affect the catalytic efficiency of these enzymes, are more sensitive to temperature denaturing, and affect the stability of the overall protein when compared to the wild type WT-G6PD. In the variants, the exposure of more and buried hydrophobic pockets was induced and monitored with 8-Anilinonaphthalene-1-sulfonic acid (ANS) fluorescence, directly affecting the compaction of structure at different levels and probably reducing the stability of the protein. The degree of functional and structural perturbation by each variant correlates with the clinical severity reported in different patients. PMID:26633385

  18. Prevalence of thalassaemia, iron-deficiency anaemia and glucose-6-phosphate dehydrogenase deficiency among Arab migrating nomad children, southern Islamic Republic of Iran.

    PubMed

    Pasalar, M; Mehrabani, D; Afrasiabi, A; Mehravar, Z; Reyhani, I; Hamidi, R; Karimi, M

    2014-12-17

    This study investigated the prevalence of iron-deficiency anaemia, glucose-6-phosphate dehydrogenase (G6PD) deficiency and β-thalassaemia trait among Arab migrating nomad children in southern Islamic Republic of Iran. Blood samples were analysed from 134 schoolchildren aged < 18 years (51 males, 83 females). Low serum ferritin (< 12 ng/dL) was present in 17.9% of children (21.7% in females and 11.8% in males). Low haemoglobin (Hb) correlated significantly with a low serum ferritin. Only 1 child had G6PD deficiency. A total of 9.7% of children had HbA2 ≥ 3.5 g/dL, indicating β-thalassaemia trait (10.8% in females and 7.8% in males). Mean serum iron, serum ferritin and total iron binding capacity were similar in males and females. Serum ferritin index was as accurate as Hb index in the diagnosis of iron-deficiency anaemia. A high prevalence of β-thalassaemia trait was the major potential risk factor in this population.

  19. A new glucose-6-phosphate dehydrogenase variant, G6PD Orissa (44 Ala{yields}Gly), is the major polymorphic variant in tribal populations in India

    SciTech Connect

    Kaeda, J.S.; Bautista, J.M.; Stevens, D.

    1995-12-01

    Deficiency of glucose-6-phosphate dehydrogenase (G6PD) is usually found at high frequencies in areas of the world where malaria has been epidemic. The frequency and genetic basis of G6PD deficiency have been studied in Africa, around the Mediterranean, and in the Far East, but little such information is available about the situation in India. To determine the extent of heterogeneity of G6PD, we have studied several different Indian populations by screening for G6PD deficiency, followed by molecular analysis of deficient alleles. The frequency of G6PD deficiency varies between 3% and 15% in different tribal and urban groups. Remarkably, a previously unreported deficient variant, G6PD Orissa (44 Ala{yields}Gly), is responsible for most of the G6PD deficiency in tribal Indian populations but is not found in urban populations, where most of the G6PD deficiency is due to the G6PD Mediterranean (188 Ser{yields}Phe) variant. The K{sup NADP}{sub m} of G6PD Orissa is fivefold higher than that of the normal enzyme. This may be due to the fact that the alanine residue that is replaced by glycine is part of a putative coenzyme-binding site. 37 refs., 2 figs., 3 tabs.

  20. The role of reduced glutathione during the course of acute haemolysis in glucose-6-phosphate dehydrogenase deficient patients: clinical and pharmacodynamic aspects.

    PubMed

    Corbucci, G G

    1990-01-01

    Tissue hypoperfusion leads to cellular oxidative and peroxidative damage due to biochemical disorders in the oxygen and substrate metabolism. The metabolic turnover of glutathione (GSH) represents one the main cytoprotective systems against the peroxide attack and the depletion or defect in resynthesis of this compound is accompanied by pathological consequences. In the present study the clinical effects of glutathione depletion were investigated in conditions of acute tissue hypoxia due to marked haemolysis in glucose-6-phosphate dehydrogenase deficient patients (favism syndrome). In these subjects a significant marker of the tissue oxidative damage was represented by the uric acid blood levels, presumably linked to xanthine-hypoxanthine altered metabolism. To antagonize the effects of oxyradical pathology, reduced glutathione was administered to a group of patients and the results confirmed the cytoprotective role played by the GSH supplementation. The GSH action was evident on the tissue metabolism and this supports the opinion that reduced glutathione could represent a new and interesting therapeutic approach in marked and acute hypoxic conditions.

  1. Red blood cell indices and prevalence of hemoglobinopathies and glucose 6 phosphate dehydrogenase deficiencies in male Tanzanian residents of Dar es Salaam.

    PubMed

    Mwakasungula, Solomon; Schindler, Tobias; Jongo, Said; Moreno, Elena; Kamaka, Kasimu; Mohammed, Mgeni; Joseph, Selina; Rashid, Ramla; Athuman, Thabit; Tumbo, Anneth Mwasi; Hamad, Ali; Lweno, Omar; Tanner, Marcel; Shekalaghe, Seif; Daubenberger, Claudia A

    2014-01-01

    Hemoglobinopathies, disorders of hemoglobin structure and production, are one of the most common monogenic disorders in humans. Glucose 6 phosphate dehydrogenase deficiency (G6PD) is an inherited enzymopathy resulting in increased oxygen stress susceptibility of red blood cells. The distributions of these genetic traits in populations living in tropical and subtropical regions where malaria has been or is still present are thought to result from survival advantage against severe life threatening malaria disease. 384 male Tanzanian volunteers residing in Dar es Salaam were typed for G6PD, sickle cell disease and α-thalassemia. The most prominent red blood cell polymorphism was heterozygous α(+)-thalassemia (37.8%), followed by the G6PD(A) deficiency (16.4%), heterozygous sickle cell trait (15.9%), G6PD(A-) deficiency (13.5%) and homozygous α(+)-thalassemia (5.2%). 35%, 45%, 17% and 3% of these volunteers were carriers of wild type gene loci, one, two or three of these hemoglobinopathies, respectively. We find that using a cut off value of 28.6 pg. for mean corpuscular hemoglobin (MCH), heterozygous α(+)-thalassemia can be predicted with a sensitivity of 84% and specificity of 72% in this male population. All subjects carrying homozygous α(+)-thalassemia were identified based on their MCH value < 28.6 pg.

  2. Involvement of ABA- and H2O2-dependent cytosolic glucose-6-phosphate dehydrogenase in maintaining redox homeostasis in soybean roots under drought stress.

    PubMed

    Wang, Huahua; Yang, Lidan; Li, Yan; Hou, Junjie; Huang, Junjun; Liang, Weihong

    2016-10-01

    The roles of abscisic acid (ABA) and hydrogen peroxide (H2O2) in inducing glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) activity and the possible roles of G6PDH in regulating ascorbate-glutathione (AsA-GSH) cycle were investigated in soybean (Glycine max L.) roots under drought stress. Drought caused a marked increase of the total and cytosolic G6PDH activities and triggered a rapid ABA and H2O2 accumulation in soybean roots. Exogenous ABA or H2O2 treatment elevated the total and cytosolic G6PDH activities, whereas suppressing ABA or H2O2 production inhibited the drought-induced increase in total and cytosolic G6PDH activities, suggesting that ABA and H2O2 are required for drought-induced increase of total G6PDH activity, namely cytosolic G6PDH activity. Furthermore, ABA induced H2O2 production by stimulating NADPH oxidase activity under drought stress. Moreover, drought significantly increased the contents of AsA and GSH and the activities of key enzymes in AsA-GSH cycle, while application of G6PDH inhibitor to seedlings significantly reduced the above effect induced by drought. Taken together, these results indicate that H2O2 acting as a downstream signaling molecule of ABA mediates drought-induced increase in cytosolic G6PDH activity, and that enhanced cytosolic G6PDH activity maintains cellular redox homeostasis by regulating AsA-GSH cycle in soybean roots. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  3. Chemical modification of lysozyme, glucose 6-phosphate dehydrogenase, and bovine eye lens proteins induced by peroxyl radicals: role of oxidizable amino acid residues.

    PubMed

    Arenas, Andrea; López-Alarcón, Camilo; Kogan, Marcelo; Lissi, Eduardo; Davies, Michael J; Silva, Eduardo

    2013-01-18

    Chemical and structural alterations to lysozyme (LYSO), glucose 6-phosphate dehydrogenase (G6PD), and bovine eye lens proteins (BLP) promoted by peroxyl radicals generated by the thermal decomposition of 2,2'-azobis(2-amidinopropane) hydrochloride (AAPH) under aerobic conditions were investigated. SDS-PAGE analysis of the AAPH-treated proteins revealed the occurrence of protein aggregation, cross-linking, and fragmentation; BLP, which are naturally organized in globular assemblies, were the most affected proteins. Transmission electron microscopy (TEM) analysis of BLP shows the formation of complex protein aggregates after treatment with AAPH. These structural modifications were accompanied by the formation of protein carbonyl groups and protein hydroperoxides. The yield of carbonyls was lower than that for protein hydroperoxide generation and was unrelated to protein fragmentation. The oxidized proteins were also characterized by significant oxidation of Met, Trp, and Tyr (but not other) residues, and low levels of dityrosine. As the dityrosine yield is too low to account for the observed cross-linking, we propose that aggregation is associated with tryptophan oxidation and Trp-derived cross-links. It is also proposed that Trp oxidation products play a fundamental role in nonrandom fragmentation and carbonyl group formation particularly for LYSO and G6PD. These data point to a complex mechanism of peroxyl-radical mediated modification of proteins with monomeric (LYSO), dimeric (G6PD), and multimeric (BLP) structural organization, which not only results in oxidation of protein side chains but also gives rise to radical-mediated protein cross-links and fragmentation, with Trp species being critical intermediates.

  4. Haptoglobin, alpha-thalassaemia and glucose-6-phosphate dehydrogenase polymorphisms and risk of abnormal transcranial Doppler among patients with sickle cell anaemia in Tanzania.

    PubMed

    Cox, Sharon E; Makani, Julie; Soka, Deogratias; L'Esperence, Veline S; Kija, Edward; Dominguez-Salas, Paula; Newton, Charles R J; Birch, Anthony A; Prentice, Andrew M; Kirkham, Fenella J

    2014-06-01

    Transcranial Doppler ultrasonography measures cerebral blood flow velocity (CBFv) of basal intracranial vessels and is used clinically to detect stroke risk in children with sickle cell anaemia (SCA). Co-inheritance in SCA of alpha-thalassaemia and glucose-6-phosphate dehydrogenase (G6PD) polymorphisms is reported to associate with high CBFv and/or risk of stroke. The effect of a common functional polymorphism of haptoglobin (HP) is unknown. We investigated the effect of co-inheritance of these polymorphisms on CBFv in 601 stroke-free Tanzanian SCA patients aged <24 years. Homozygosity for alpha-thalassaemia 3·7 deletion was significantly associated with reduced mean CBFv compared to wild-type (β-coefficient -16·1 cm/s, P = 0·002) adjusted for age and survey year. Inheritance of 1 or 2 alpha-thalassaemia deletions was associated with decreased risk of abnormally high CBFv, compared to published data from Kenyan healthy control children (Relative risk ratio [RRR] = 0·53 [95% confidence interval (CI):0·35-0·8] & RRR = 0·43 [95% CI:0·23-0·78]), and reduced risk of abnormally low CBFv for 1 deletion only (RRR = 0·38 [95% CI:0·17-0·83]). No effects were observed for G6PD or HP polymorphisms. This is the first report of the effects of co-inheritance of common polymorphisms, including the HP polymorphism, on CBFv in SCA patients resident in Africa and confirms the importance of alpha-thalassaemia in reducing risk of abnormal CBFv.

  5. A trade off between catalytic activity and protein stability determines the clinical manifestations of glucose-6-phosphate dehydrogenase (G6PD) deficiency.

    PubMed

    Boonyuen, Usa; Chamchoy, Kamonwan; Swangsri, Thitiluck; Junkree, Thanyaphorn; Day, Nicholas P J; White, Nicholas J; Imwong, Mallika

    2017-11-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common polymorphism and enzymopathy in humans, affecting approximately 400 million people worldwide. It is responsible for various clinical manifestations, including favism, hemolytic anemia, chronic non-spherocytic hemolytic anemia, spontaneous abortion, and neonatal hyperbilirubinemia. Understanding the molecular mechanisms underlying the severity of G6PD deficiency is of great importance but that of many G6PD variants are still unknown. In this study, we report the construction, expression, purification, and biochemical characterization in terms of kinetic properties and stability of five clinical G6PD variants-G6PD Bangkok, G6PD Bangkok noi, G6PD Songklanagarind, G6PD Canton+Bangkok noi, and G6PD Union+Viangchan. G6PD Bangkok and G6PD Canton+Bangkok noi showed a complete loss of catalytic activity and moderate reduction in thermal stability when compared with the native G6PD. G6PD Bangkok noi and G6PD Union+Viangchan showed a significant reduction in catalytic efficiency, whereas G6PD Songklanagarind showed a catalytic activity comparable to the wild-type enzyme. The Union+Viangchan mutation showed a remarkable effect on the global stability of the enzyme. In addition, our results indicate that the location of mutations in G6PD variants affects their catalytic activity, stability, and structure. Hence, our results provide a molecular explanation for clinical manifestations observed in individuals with G6PD deficiency. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  6. Starvation actively inhibits splicing of glucose-6-phosphate dehydrogenase mRNA via a bifunctional ESE/ESS element bound by hnRNP K.

    PubMed

    Cyphert, T J; Suchanek, A L; Griffith, B N; Salati, L M

    2013-09-01

    Regulated expression of glucose-6-phosphate dehydrogenase (G6PD) is due to changes in the rate of pre-mRNA splicing and not changes in its transcription. Starvation alters pre-mRNA splicing by decreasing the rate of intron removal, leading to intron retention and a decrease in the accumulation of mature mRNA. A regulatory element within exon 12 of G6PD pre-mRNA controls splicing efficiency. Starvation caused an increase in the expression of heterogeneous nuclear ribonucleoprotein (hnRNP) K protein and this increase coincided with the increase in the binding of hnRNP K to the regulatory element and a decrease in the expression of G6PD mRNA. HnRNP K bound to two C-rich motifs forming an ESS within exon 12. Overexpression of hnRNP K decreased the splicing and expression of G6PD mRNA, while siRNA-mediated depletion of hnRNP K caused an increase in the splicing and expression of G6PD mRNA. Binding of hnRNP K to the regulatory element was enhanced in vivo by starvation coinciding with a decrease in G6PD mRNA. HnRNP K binding to the C-rich motifs blocked binding of serine-arginine rich, splicing factor 3 (SRSF3), a splicing enhancer. Thus hnRNP K is a nutrient regulated splicing factor responsible for the inhibition of the splicing of G6PD during starvation.

  7. Glucose-6-phosphate dehydrogenase and alternative oxidase are involved in the cross tolerance of highland barley to salt stress and UV-B radiation.

    PubMed

    Zhao, Chengzhou; Wang, Xiaomin; Wang, Xiaoyu; Wu, Kunlun; Li, Ping; Chang, Ning; Wang, Jianfeng; Wang, Feng; Li, Jiaolong; Bi, Yurong

    2015-06-01

    In this study, a new mechanism involving glucose-6-phosphate dehydrogenase (G6PDH) and alternative pathways (AP) in salt pretreatment-induced tolerance of highland barley to UV-B radiation was investigated. When highland barley was exposed to UV-B radiation, the G6PDH activity decreased but the AP capacity increased. In contrast, under UV-B+NaCl treatment, the G6PDH activity was restored to the control level and the maximal AP capacity and antioxidant enzyme activities were reached. Glucosamine (Glucm, an inhibitor of G6PDH) obviously inhibited the G6PDH activity in highland barley under UV-B + NaCl treatment and a similar pattern was observed in reduced glutathione (GSH) and ascorbic acid (Asc) contents. Similarly, salicylhydroxamic acid (SHAM, an inhibitor of AOX) significantly reduced the AP capacity in highland barley under UV-B + NaCl treatment. The UV-B-induced hydrogen peroxide (H2O2) accumulation was also followed. Further studies indicated that non-functioning of G6PDH or AP under UV-B+NaCl + Glucm or UV-B + NaCl + SHAM treatment also caused damages in photosynthesis and stomatal movement. Western blot analysis confirmed that the alternative oxidase (AOX) and G6PDH were dependent each other in cross tolerance to UV-B and salt. The inhibition of AP or G6PDH activity resulted in a significant accumulation or reduction of NADPH content, respectively, under UV-B+NaCl treatment in highland barley leaves. Taken together, our results indicate that AP and G6PDH mutually regulate and maintain photosynthesis and stomata movement in the cross adaptation of highland barley seedlings to UV-B and salt by modulating redox homeostasis and NADPH content.

  8. Elevated glucose-6-phosphate dehydrogenase expression in the cervical cancer cases is associated with the cancerigenic event of high-risk human papillomaviruses

    PubMed Central

    Hu, Tao; Li, Ya-Shan; Chen, Bo; Chang, Ye-Fei; Liu, Guang-Cai; Hong, Ying; Chen, Hong-Lan

    2015-01-01

    The most important etiologic agent in the pathogenesis of cervical cancers (CCs) is human papillomavirus (HPV), while the mechanisms underlying are still not well known. Glucose-6-phosphate dehydrogenase (G6PD) is reported to elevate in various tumor cells. However, no available references elucidated the correlation between the levels of G6PD and HPV-infected CC until now. In the present study, we explored the possible role of G6PD in the pathology of CC induced by HPV infection. Totally 48 patients with HPV + CC and another 63 healthy women enrolled in the clinical were employed in the present study. Overall, prevalence of cervical infection with high-risk-HPV (HR-HPV) type examined was HPV-16, followed by HPV-18. The expressions of G6PD in CC samples were also detected by immunohistochemistry (IHC), qRT-PCR, and Western blot. Regression analysis showed elevated G6PD level was positively correlated with the CC development in 30–40 aged patients with HR-HPV-16/18 infection. The HPV16 + Siha, HPV18 + Hela, and HPV-C33A cell lines were employed and transfected with G6PD deficient vectors developed in vitro. MTT and flow cytometry were also employed to determine the survival and apoptosis of CC cells after G6PD expressional inhibition. Our data revealed that G6PD down-regulation induced poor proliferation and more apoptosis of HPV18 + Hela cells, when compared with that of HPV16 + Siha and HPV-C33A cells. These findings suggest that G6PD expressions in the HR-HPV + human CC tissues and cell lines play an important role in tumor growth and proliferation. PMID:25616277

  9. Glucose-6-phosphate dehydrogenase deficiency does not increase the susceptibility of sperm to oxidative stress induced by H2O2.

    PubMed

    Roshankhah, Shiva; Rostami-Far, Zahra; Shaveisi-Zadeh, Farhad; Movafagh, Abolfazl; Bakhtiari, Mitra; Shaveisi-Zadeh, Jila

    2016-12-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme defect. G6PD plays a key role in the pentose phosphate pathway, which is a major source of nicotinamide adenine dinucleotide phosphate (NADPH). NADPH provides the reducing equivalents for oxidation-reduction reductions involved in protecting against the toxicity of reactive oxygen species such as H2O2. We hypothesized that G6PD deficiency may reduce the amount of NADPH in sperms, thereby inhibiting the detoxification of H2O2, which could potentially affect their motility and viability, resulting in an increased susceptibility to infertility. Semen samples were obtained from four males with G6PD deficiency and eight healthy males as a control. In both groups, motile sperms were isolated from the seminal fluid and incubated with 0, 10, 20, 40, 60, 80, and 120 µM concentrations of H2O2. After 1 hour incubation at 37℃, sperms were evaluated for motility and viability. Incubation of sperms with 10 and 20 µM H2O2 led to very little decrease in motility and viability, but motility decreased notably in both groups in 40, 60, and 80 µM H2O2, and viability decreased in both groups in 40, 60, 80, and 120 µM H2O2. However, no statistically significant differences were found between the G6PD-deficient group and controls. G6PD deficiency does not increase the susceptibility of sperm to oxidative stress induced by H2O2, and the reducing equivalents necessary for protection against H2O2 are most likely produced by other pathways. Therefore, G6PD deficiency cannot be considered as major risk factor for male infertility.

  10. Glucose-6-phosphate dehydrogenase deficiency does not increase the susceptibility of sperm to oxidative stress induced by H2O2

    PubMed Central

    Roshankhah, Shiva; Rostami-Far, Zahra; Shaveisi-Zadeh, Farhad; Movafagh, Abolfazl; Shaveisi-Zadeh, Jila

    2016-01-01

    Objective Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme defect. G6PD plays a key role in the pentose phosphate pathway, which is a major source of nicotinamide adenine dinucleotide phosphate (NADPH). NADPH provides the reducing equivalents for oxidation-reduction reductions involved in protecting against the toxicity of reactive oxygen species such as H2O2. We hypothesized that G6PD deficiency may reduce the amount of NADPH in sperms, thereby inhibiting the detoxification of H2O2, which could potentially affect their motility and viability, resulting in an increased susceptibility to infertility. Methods Semen samples were obtained from four males with G6PD deficiency and eight healthy males as a control. In both groups, motile sperms were isolated from the seminal fluid and incubated with 0, 10, 20, 40, 60, 80, and 120 µM concentrations of H2O2. After 1 hour incubation at 37℃, sperms were evaluated for motility and viability. Results Incubation of sperms with 10 and 20 µM H2O2 led to very little decrease in motility and viability, but motility decreased notably in both groups in 40, 60, and 80 µM H2O2, and viability decreased in both groups in 40, 60, 80, and 120 µM H2O2. However, no statistically significant differences were found between the G6PD-deficient group and controls. Conclusion G6PD deficiency does not increase the susceptibility of sperm to oxidative stress induced by H2O2, and the reducing equivalents necessary for protection against H2O2 are most likely produced by other pathways. Therefore, G6PD deficiency cannot be considered as major risk factor for male infertility. PMID:28090457

  11. Serum Soluble Transferrin Receptor Concentrations Are Elevated in Congolese Children with Glucose-6-Phosphate Dehydrogenase Variants, but Not Sickle Cell Variants or α-Thalassemia.

    PubMed

    Barker, Mikaela K; Henderson, Amanda M; Naguib, Karimah; Vercauteren, Suzanne M; Devlin, Angela M; Albert, Arianne Y; Bahizire, Esto; Tugirimana, Pierrot L; Akilimali, Pierre Z; Boy, Erick; Green, Tim J; Karakochuk, Crystal D

    2017-09-01

    Background: Anemia is common in Congolese children, and inherited blood disorders may be a contributing cause. The presence of sickle cell variants, X-linked glucose-6-phosphate dehydrogenase (G6PD) deficiency and α-thalassemia, has been previously reported. G6PD A- deficiency is characterized by the co-inheritance of G6PD 376 and 202 variants and is common in sub-Saharan Africa.Objective: We aimed to measure the associations between inherited blood disorders and hemoglobin, ferritin, and soluble transferrin receptor (sTfR) concentrations in Congolese children.Methods: Venous blood was collected from 744 children aged 6-59 mo from 2 provinces. We measured biomarkers of nutritional and inflammation status and malaria. Pyrosequencing was used to detect sickle cell variants. Polymerase chain reaction was used to detect G6PD variants and α-thalassemia deletions.Results: Overall, 11% of children had a sickle cell variant, 19% of boys were G6PD A- hemizygotes, 12% and 10% of girls were G6PD A- hetero- or homozygotes, respectively, and 12% of children had α-thalassemia. Multivariable linear regression models (adjusted for age, province, altitude, malaria, and biomarkers of nutritional and inflammation status) showed that G6PD A- hemizygous boys and G6PD 376 homozygous girls had higher sTfR concentrations [geometric mean ratios (95% CIs): 1.20 (1.03, 1.39) and 1.25 (1.02, 1.53), respectively] than children with no G6PD variants. Hemoglobin and ferritin concentrations were not independently associated with any of the inherited blood disorder genotypes.Conclusions: We found that 2 G6PD variant genotypes were associated with elevated sTfR concentrations, which limits the accuracy of sTfR as a biomarker of iron status in this population. © 2017 American Society for Nutrition.

  12. Nine different glucose-6-phosphate dehydrogenase (G6PD) variants in a Malaysian population with Malay, Chinese, Indian and Orang Asli (aboriginal Malaysian) backgrounds.

    PubMed

    Wang, Jichun; Luo, Enjie; Hirai, Makoto; Arai, Meiji; Abdul-Manan, Eas; Mohamed-Isa, Zaleha; Hidayah, Ni; Matsuoka, Hiroyuki

    2008-10-01

    The Malaysian people consist of several ethnic groups including the Malay, the Chinese, the Indian and the Orang Asli (aboriginal Malaysians). We collected blood samples from outpatients of 2 hospitals in the State of Selangor and identified 27 glucose-6-phosphate dehydrogenase (G6PD)-deficient subjects among these ethnic groups. In the Malay, G6PD Viangchan (871GA, 1311CT, IVS11 nt93TC) and G6PD Mahidol (487GA) types, which are common in Cambodia and Myanmar, respectively, were detected. The Malay also had both subtypes of G6PD Mediterranean:the Mediterranean subtype (563CT, 1311CT, IVS11 nt93TC) and the Indo-Pakistan subtype (563CT, 1311C, IVS11 nt93T). In Malaysians of Chinese background, G6PD Kaiping (1388GA), G6PD Canton (1376GT) and G6PD Gaohe (95AG), which are common in China, were detected. Indian Malaysians possessed G6PD Mediterranean (Indo-Pakistan subtype) and G6PD Namoru (208TC), a few cases of which had been reported in Vanuatu and many in India. Our findings indicate that G6PD Namoru occurs in India and flows to Malaysia up to Vanuatu. We also discovered 5 G6PD-deficient cases with 2 nucleotide substitutions of 1311CT and IVS11 nt93TC, but without amino-acid substitution in the G6PD molecule. These results indicate that the Malaysian people have incorporated many ancestors in terms of G6PD variants.

  13. Starvation actively inhibits splicing of glucose-6-phosphate dehydrogenase mRNA via a bifunctional ESE/ESS element bound by hnRNP K

    PubMed Central

    Cyphert, T.J.; Suchanek, A.L.; Griffith, B.N.; Salati, L.M.

    2013-01-01

    Regulated expression of glucose-6-phosphate dehydrogenase (G6PD) is due to changes in the rate of pre-mRNA splicing and not changes in its transcription. Starvation alters pre-mRNA splicing by decreasing the rate of intron removal, leading to intron retention and a decrease in the accumulation of mature mRNA. A regulatory element within exon 12 of G6PD pre-mRNA controls splicing efficiency. Starvation caused an increase in the expression of heterogeneous nuclear ribonucleoprotein (hnRNP) K protein and this increase coincided with the increase in the binding of hnRNP K to the regulatory element and a decrease in the expression of G6PD mRNA. HnRNP K bound to two C-rich motifs forming an ESS within exon 12. Overexpression of hnRNP K decreased the splicing and expression of G6PD mRNA, while siRNA-mediated depletion of hnRNP K caused an increase in the splicing and expression of G6PD mRNA. Binding of hnRNP K to the regulatory element was enhanced in vivo by starvation coinciding with a decrease in G6PD mRNA. HnRNP K binding to the C-rich motifs blocked binding of serine-arginine rich, splicing factor 3 (SRSF3), a splicing enhancer. Thus hnRNP K is a nutrient regulated splicing factor responsible for the inhibition of the splicing of G6PD during starvation. PMID:23631859

  14. Anti-citrullinated glucose-6-phosphate isomerase peptide antibodies in patients with rheumatoid arthritis are associated with HLA-DRB1 shared epitope alleles and disease activity

    PubMed Central

    Umeda, N; Matsumoto, I; Ito, I; Kawasaki, A; Tanaka, Y; Inoue, A; Tsuboi, H; Suzuki, T; Hayashi, T; Ito, S; Tsuchiya, N; Sumida, T

    2013-01-01

    To identify and characterize anti-citrullinated glucose-6-phosphate isomerase (GPI) peptide antibodies in patients with rheumatoid arthritis (RA). Nine GPI arginine-bearing peptides in human GPI protein were selected and cyclic citrullinated GPI peptides (CCG-1–9) were constructed. Samples were obtained from RA (n = 208), systemic lupus erythematosus (SLE) (n = 101), Sjögren's syndrome (SS; n = 101) and healthy controls (n = 174). Antibodies against CCG-1–9 were measured, and anti-citrullinated α-enolase-1 (CEP-1), -cyclic citrullinated peptides (CCP) and -GPI proteins antibodies were also examined. Patients with RA were genotyped for HLA-DRB1. The numbers of shared epitope (SE) alleles were counted and compared with those of the autoantibodies. Rabbit GPI was citrullinated with rabbit peptidylarginine deiminase and immunoblot analysis of RA sera performed. The levels of autoantibodies were compared before and after treatment with TNF antagonists in 58 RA patients. Anti-CCG-2, -4 and -7 antibodies were detected in 25·5, 33·2 and 37·0% patients with RA, respectively, and these antibodies were very specific for RA (specificity, 98·1–99·7%). Altogether, 44·2, 86·1 and 13·9% of RA sera were positive for anti-CEP-1, -CCP and -GPI protein antibodies, respectively. Anti-CCG-2, -4 and -7 antibodies were correlated with anti-CCP and anti-CEP-1 antibodies and with the presence of HLA-DRB1 SE alleles. Citrullinated GPI protein was detected using RA sera. Treatment with tumour necrosis factor antagonists reduced significantly the levels of anti-CCG-2 and -7 but not of anti-CEP-1 antibodies. This is the first report documenting the presence of anti-CCG antibodies in RA. Anti-CCG-2 and -7 antibodies could be considered as markers for the diagnosis of RA and its disease activity. PMID:23480184

  15. Red cell glucose 6-phosphate dehydrogenase deficiency in the northern region of Turkey: is G6PD deficiency exclusively a male disease?

    PubMed

    Albayrak, Canan; Albayrak, Davut

    2015-03-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked recessive genetic defect that can cause hemolytic crisis. However, this disease affects both males and females. In Turkey, the frequency of this enzyme deficiency was reported to vary, from 0.25 to 18%, by the geographical area. Its prevalence in the northern Black Sea region of Turkey is unknown. The aims of this study were to assess the prevalence of G6PD deficiency in the northern region Turkey in children and adults with hyperbilirubinemia and hemolytic anemia. This report included a total of 976 G6PD enzyme results that were analyzed between May 2005 and January 2014. G6PD deficiency was detected in 5.0% of all patients. G6PD deficiency was significantly less frequent in females (1.9%, 6/323) than in males (6.6%, 43/653). G6PD deficiency was detected in 3.7% of infants with hyperbilirubinemia, 9.2% of children, and 4.5% of adults with hemolytic anemia. In both the newborn group and the group of children, G6PD deficiency was significantly more frequent in males. In the combined group of children (groups I and II), the proportion of males was 74% and 67% in all groups (P = .0008). In conclusion, in northern region of Turkey, G6PD deficiency is an important cause of neonatal hyperbilirubinemia and hemolytic crisis in children and adults. This study suggests that most pediatricians thought that G6PD deficiency is exclusively a male disease. For this reason, some female patients may have been undiagnosed.

  16. Glucose-6-Phosphate Dehydrogenase Enhances Antiviral Response through Downregulation of NADPH Sensor HSCARG and Upregulation of NF-κB Signaling

    PubMed Central

    Wu, Yi-Hsuan; Chiu, Daniel Tsun-Yee; Lin, Hsin-Ru; Tang, Hsiang-Yu; Cheng, Mei-Ling; Ho, Hung-Yao

    2015-01-01

    Glucose-6-phosphate dehydrogenase (G6PD)-deficient cells are highly susceptible to viral infection. This study examined the mechanism underlying this phenomenon by measuring the expression of antiviral genes—tumor necrosis factor alpha (TNF-α) and GTPase myxovirus resistance 1 (MX1)—in G6PD-knockdown cells upon human coronavirus 229E (HCoV-229E) and enterovirus 71 (EV71) infection. Molecular analysis revealed that the promoter activities of TNF-α and MX1 were downregulated in G6PD-knockdown cells, and that the IκB degradation and DNA binding activity of NF-κB were decreased. The HSCARG protein, a nicotinamide adenine dinucleotide phosphate (NADPH) sensor and negative regulator of NF-κB, was upregulated in G6PD-knockdown cells with decreased NADPH/NADP+ ratio. Treatment of G6PD-knockdown cells with siRNA against HSCARG enhanced the DNA binding activity of NF-κB and the expression of TNF-α and MX1, but suppressed the expression of viral genes; however, the overexpression of HSCARG inhibited the antiviral response. Exogenous G6PD or IDH1 expression inhibited the expression of HSCARG, resulting in increased expression of TNF-α and MX1 and reduced viral gene expression upon virus infection. Our findings suggest that the increased susceptibility of the G6PD-knockdown cells to viral infection was due to impaired NF-κB signaling and antiviral response mediated by HSCARG. PMID:26694452

  17. First evaluation of glucose-6-phosphate dehydrogenase (G6PD) deficiency in vivax malaria endemic regions in the Republic of Korea.

    PubMed

    Goo, Youn-Kyoung; Ji, So-Young; Shin, Hyun-Il; Moon, Jun-Hye; Cho, Shin-Hyung; Lee, Won-Ja; Kim, Jung-Yeon

    2014-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme defect and affects more than 400 million people worldwide. This deficiency is believed to protect against malaria because its global distribution is similar. However, this genetic disorder may be associated with potential hemolytic anemia after treatment with anti-malarials, primaquine or other 8-aminoquinolines. Although primaquine is used for malaria prevention, no study has previously investigated the prevalence of G6PD variants and G6PD deficiency in the Republic of Korea (ROK). Two commercialized test kits (Trinity G-6-PDH and CareStart G6PD test) were used for G6PD deficiency screening. The seven common G6PD variants were investigated by DiaPlexC kit in blood samples obtained living in vivax malaria endemic regions in the ROK. Of 1,044 blood samples tested using the CareStart G6PD test, none were positive for G6PD deficiency. However, a slightly elevated level of G6PD activity was observed in 14 of 1,031 samples tested with the Trinity G-6-PDH test. Forty-nine of the 298 samples with non-specific amplification by DiaPlexC kit were confirmed by sequencing to be negative for the G6PD variants. No G6PD deficiency was observed using phenotypic- or genetic-based tests in individuals residing in vivax malaria endemic regions in the ROK. Because massive chemoprophylaxis using primaquine has been performed in the ROK military to kill hypnozoites responsible for relapse and latent stage vivax malaria, further regular monitoring is essential for the safe administration of primaquine.

  18. Practical approach for characterization of glucose 6-phosphate dehydrogenase (G6PD) deficiency in countries with population ethnically heterogeneous: description of seven new G6PD mutants.

    PubMed

    Moradkhani, Kamran; Mekki, Chadia; Bahuau, Michel; Te, Valerie Li Thiao; Holder, Muriel; Pissard, Serge; Préhu, Claude; Rose, Christian; Wajcman, Henri; Galactéros, Frédéric

    2012-02-01

    We present a rapid strategy based on Restriction Fragment Length Polymorphism (RFLP) analysis to characterize the more frequent glucose 6-phosphate dehydrogenase (G6PD) variants observed in a population with high gene flow. During a study involving more than 600 patients, we observed mainly G6PD A(-) (c.202G>A, c.376A>G; p.Val68Met, p.Asn126Asp), G6PD Mediterranean (Med) (c.563C>T, p.Ser188Phe), and G6PD Betica (c.376A>G, 542A>T; p.126Asn>Asp, 181Asp>Val) with addition of a few rare ones. A number of 10 abnormalities amounted to 92% of all the molecular defects. In addition, seven new mutations were found: three presented with acute hemolytic anemia following oxidative stress [G6PD Nice (c.1380G>C, p.Glu460Asp), G6PD Roubaix (c.811G>C, p.Val271Leu), and G6PD Toledo (c.496C>T, p.Arg166Cys)], three with different degrees of chronic hemolytic anemia [G6PD Lille (c.821A>T, p.Glu274Val), G6PD Villeurbanne (c.1000_1002delACC, p.Thr334del), and G6PD Amiens (c.1367A>T, p.Asp456Val)] and one found fortuitously G6PD Montpellier (c.1132G>A, p.Gly378Ser).

  19. Aggregation ability of erythrocytes of patients with coronary heart disease depending on different glucose concentration

    NASA Astrophysics Data System (ADS)

    Malinova, Lidia I.; Simonenko, Georgy V.; Kirichuk, Vyacheslav F.; Denisova, Tatyana P.; Tuchin, Valery V.

    2002-07-01

    The aggregation ability of erythrocytes of patients with coronary heart disease comparing to practically healthy persons and patients with coronary heart disease combined with non insulin dependent diabetes mellitus depending on different glucose concentration in unguentums of blood incubates with the help of computer microphotometer - visual analyzer was studied. Two-phase behavior of erythrocytes size changing of practically healthy persons depending on glucose concentration in an incubation medium and instability erythrocyte systems of a whole blood to the influence of high glucose concentration were revealed. Influence of high glucose concentration on aggregation ability of erythrocytes of patients with coronary heart disease and its combination with non insulin dependent diabetes mellitus was revealed.

  20. Purification of glucose-6-phosphate dehydrogenase and glutathione reductase enzymes from the gill tissue of Lake Van fish and analyzing the effects of some chalcone derivatives on enzyme activities.

    PubMed

    Kuzu, Muslum; Aslan, Abdulselam; Ahmed, Ishtiaq; Comakli, Veysel; Demirdag, Ramazan; Uzun, Naim

    2016-04-01

    Glucose-6-phosphate dehydrogenase (G6PD) and glutathione reductase (GR) are metabolically quite important enzymes. Within this study, these two enzymes were purified for the first time from the gills of Lake Van fish. In the purifying process, ammonium sulfate precipitation and 2',5'-ADP Sepharose 4B affinity column chromatography techniques for glucose-6-phosphate dehydrogenase, temperature degradation and 2',5'-ADP Sepharose 4B affinity column chromatography for glutathione reductase enzyme were used. The control of the enzyme purity and determination of molecular weight were done with sodium dodecyl sulfate polyacrylamide gel electrophoresis. K(M) and V(max) values were determined with Lineweaver-Burk plot. Besides, the effects of some chalcone derivatives on the purified enzymes were analyzed. For the ones showing inhibition effect, % activity-[I] figures were drawn and IC50 values were determined. K(i) value was calculated by using Cheng-Prusoff equation.

  1. Pleurotus ostreatus, an edible mushroom, enhances glucose 6-phosphate dehydrogenase, ascorbate peroxidase and reduces xanthine dehydrogenase in major organs of aged rats.

    PubMed

    Thomas, Philip Aloysius; Geraldine, Pitchairaj; Jayakumar, Thanasekaran

    2014-05-01

    Aging is now considered to be associated with an elevation in oxidative damage to macromolecules and enhanced levels of inflammation. Therefore, inhibition of age-related oxidative stress by natural supplement is an important study. To investigate whether the treatment with Pleurotus ostreatus (Jacq.: Fr) Kumm, (Pleurotaceae) can ameliorate oxidative damage in aged rats. Male Wistar rats were divided into three groups of six each: group 1, normal young rats; group 2, normal aged untreated rats; group 3, normal aged rats treated with P. ostreatus (200 mg/kg body wt administered intraperitoneally for 21 days). On the 22nd day, rats were sacrificed by decapitation; the liver, kidneys, heart and brain were removed from each rat for the biochemical and isozyme analyses of the antioxidant enzymes glucose 6-phosphate dehydrogenase (G6PDH), ascorbate peroxidase (Apx) and xanthine dehydrogenase (XDH). An elevated activity of XDH was observed in the liver (G2:13.72 ± 4.1 versus G1: 7.57 ± 1.15; p < 0.05), kidneys (G2:101.48 ± 12.3 versus G1: 31.15 ± 1.71; p < 0.01), heart (G2: 63.21 ± 3.96 versus G1: 37.3 ± 2.70; p < 0.01) and brain (G2: 39.02 ± 3.96 versus G1: 19.84 ± 1.22; p < 0.001). The activities of G6PDH and Apx were lowered in major organs of aged untreated rats. However, treatment of P. ostreatus to aged rats resulted in decreased XDH and increased G6PDH and Apx activities in liver, kidneys, heart and brain. Interestingly, analyses of isozyme pattern of these enzymes are support the results obtained from the spectrophotometric determinations. These results suggest that an extract of P. ostreatus can protect the age-related oxidative damage in major organs of Wistar rats by enhancing the antioxidant enzymes G6PDH and Apx and by reducing XDH.

  2. Single-Dose Primaquine in a Preclinical Model of Glucose-6-Phosphate Dehydrogenase Deficiency: Implications for Use in Malaria Transmission-Blocking Programs.

    PubMed

    Wickham, Kristina S; Baresel, Paul C; Marcsisin, Sean R; Sousa, Jason; Vuong, Chau T; Reichard, Gregory A; Campo, Brice; Tekwani, Babu L; Walker, Larry A; Rochford, Rosemary

    2016-10-01

    Individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency (G6PDd) are at risk for developing hemolytic anemia when given the antimalarial drug primaquine (PQ). The WHO Evidence Review Group released a report suggesting that mass administration of a single dose of PQ at 0.25 mg of base/kg of body weight (mpk) (mouse equivalent of 3.125 mpk) could potentially reduce malaria transmission based on its gametocytocidal activity and could be safely administered to G6PD-deficient individuals, but there are limited safety data available confirming the optimum single dose of PQ. A single-dose administration of PQ was therefore assessed in our huRBC-SCID mouse model used to predict hemolytic toxicity with respect to G6PD deficiency. In this model, nonobese diabetic (NOD)/SCID mice are engrafted with human red blood cells (huRBC) from donors with the African or Mediterranean variant of G6PDd (A-G6PDd or Med-G6PDd, respectively) and demonstrate dose-dependent sensitivity to PQ. In mice engrafted with A-G6PD-deficient huRBC, single-dose PQ at 3.125, 6.25, or 12.5 mpk had no significant loss of huRBC compared to the vehicle control group. In contrast, in mice engrafted with Med-G6PDd huRBC, a single dose of PQ at 3.125, 6.25, or 12.5 mpk resulted in a significant, dose-dependent loss of huRBC compared to the value for the vehicle control group. Our data suggest that administration of a single low dose of 0.25 mpk of PQ could induce hemolytic anemia in Med-G6PDd individuals but that use of single-dose PQ at 0.25 mpk as a gametocytocidal drug to block transmission would be safe in areas where A-G6PDd predominates. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  3. Single-Dose Primaquine in a Preclinical Model of Glucose-6-Phosphate Dehydrogenase Deficiency: Implications for Use in Malaria Transmission-Blocking Programs

    PubMed Central

    Wickham, Kristina S.; Baresel, Paul C.; Sousa, Jason; Vuong, Chau T.; Reichard, Gregory A.; Campo, Brice; Tekwani, Babu L.; Walker, Larry A.

    2016-01-01

    Individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency (G6PDd) are at risk for developing hemolytic anemia when given the antimalarial drug primaquine (PQ). The WHO Evidence Review Group released a report suggesting that mass administration of a single dose of PQ at 0.25 mg of base/kg of body weight (mpk) (mouse equivalent of 3.125 mpk) could potentially reduce malaria transmission based on its gametocytocidal activity and could be safely administered to G6PD-deficient individuals, but there are limited safety data available confirming the optimum single dose of PQ. A single-dose administration of PQ was therefore assessed in our huRBC-SCID mouse model used to predict hemolytic toxicity with respect to G6PD deficiency. In this model, nonobese diabetic (NOD)/SCID mice are engrafted with human red blood cells (huRBC) from donors with the African or Mediterranean variant of G6PDd (A-G6PDd or Med-G6PDd, respectively) and demonstrate dose-dependent sensitivity to PQ. In mice engrafted with A-G6PD-deficient huRBC, single-dose PQ at 3.125, 6.25, or 12.5 mpk had no significant loss of huRBC compared to the vehicle control group. In contrast, in mice engrafted with Med-G6PDd huRBC, a single dose of PQ at 3.125, 6.25, or 12.5 mpk resulted in a significant, dose-dependent loss of huRBC compared to the value for the vehicle control group. Our data suggest that administration of a single low dose of 0.25 mpk of PQ could induce hemolytic anemia in Med-G6PDd individuals but that use of single-dose PQ at 0.25 mpk as a gametocytocidal drug to block transmission would be safe in areas where A-G6PDd predominates. PMID:27458212

  4. High prevalence of hemoglobin disorders and glucose-6-phosphate dehydrogenase (G6PD) deficiency in the Republic of Guinea (West Africa).

    PubMed

    Millimono, Tamba S; Loua, Kovana M; Rath, Silvia L; Relvas, Luis; Bento, Celeste; Diakite, Mandiou; Jarvis, Martin; Daries, Nathalie; Ribeiro, Leticia M; Manco, Licínio; Kaeda, Jaspal S

    2012-01-01

    Reliable and accurate epidemiological data is a prerequisite for a cost effective screening program for inherited disorders, which however, is lacking in a number of developing countries. Here we report the first detailed population study in the Republic of Guinea, a sub-Saharan West African country, designed to assess the frequency of glucose-6-phosphate dehydrogenase (G6PD) deficiency and hemoglobinopathies, including screening for thalassemia. Peripheral blood samples from 187 Guinean adults were screened for hemoglobin (Hb) variants by standard hematological methods. One hundred and ten samples from males were screened for G6PD deficiency by the fluorescent spot test. Molecular analysis was performed for the most common α-thalassemia (α-thal) deletions, β-globin gene mutations, G6PD variants B (376A), A (376G), A- (376G/202A) and Betica (376G/968C), using polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP) or sequencing. Of the 187 subjects screened, 36 were heterozygous for Hb S [β6(A3)Glu→Val, GAG>GTG] (allele frequency 9.62%). Sixty-four subjects were heterozygous and seven were homozygous for the -α(3.7) kb deletion (allele frequency 20.85%). β-Thalassemia alleles were detected in five subjects, four with the -29 (A>G) mutation (allele frequency 1.07%) and one with codon 15 (TGG>TAG) (allele frequency 0.96%). The G6PD A- and G6PD Betica deficient variants were highly prevalent with a frequency of 5.7 and 3.3%, respectively. While we did not test for ferritin levels or α(0)-thal, four females (5.2%) had red cell indices strongly suggestive of iron deficient anemia: Hb <9.7 g/dL; MCH <19.3 pg; MCV <68.2; MCHC <31.6 g/dl; RDW >19.8%. Our results are consistent with high frequency of alleles such as Hb S, α-thal and G6PD deficient alleles associated with malaria resistance. Finding a 9.6% Hb S allele frequency supports the notion for a proficient neonatal screening to identify the sickle cell patients, who might benefit

  5. Glucose-6-phosphate dehydrogenase deficiency, chlorproguanil-dapsone with artesunate and post-treatment haemolysis in African children treated for uncomplicated malaria

    PubMed Central

    2012-01-01

    Background Malaria is a leading cause of mortality, particularly in sub-Saharan African children. Prompt and efficacious treatment is important as patients may progress within a few hours to severe and possibly fatal disease. Chlorproguanil-dapsone-artesunate (CDA) was a promising artemisinin-based combination therapy (ACT), but its development was prematurely stopped because of safety concerns secondary to its associated risk of haemolytic anaemia in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals. The objective of the study was to assess whether CDA treatment and G6PD deficiency are risk factors for a post-treatment haemoglobin drop in African children <5 years of age with uncomplicated malaria. Methods This case–control study was performed in the context of a larger multicentre randomized clinical trial comparing safety and efficacy of four different ACT in children with uncomplicated malaria. Children, who after treatment experienced a haemoglobin drop ≥2 g/dl (cases) within the first four days (days 0, 1, 2, and 3), were compared with those without an Hb drop (controls). Cases and controls were matched for study site, sex, age and baseline haemoglobin measurements. Data were analysed using a conditional logistic regression model. Results G6PD deficiency prevalence, homo- or hemizygous, was 8.5% (10/117) in cases and 6.8% (16/234) in controls (p = 0.56). The risk of a Hb drop ≥2 g/dl was not associated with either G6PD deficiency (adjusted odds ratio (AOR): 0.81; p = 0.76) or CDA treatment (AOR: 1.28; p = 0.37) alone. However, patients having both risk factors tended to have higher odds (AOR: 11.13; p = 0.25) of experiencing a Hb drop ≥2 g/dl within the first four days after treatment, however this finding was not statistically significant, mainly because G6PD deficient patients treated with CDA were very few. In non-G6PD deficient individuals, the proportion of cases was similar between treatment groups while in G

  6. Glucose-6-phosphate dehydrogenase deficiency and the risk of malaria and other diseases in children in Kenya: a case-control and a cohort study

    PubMed Central

    Uyoga, Sophie; Ndila, Carolyne M; Macharia, Alex W; Nyutu, Gideon; Shah, Shivang; Peshu, Norbert; Clarke, Geraldine M; Kwiatkowski, Dominic P; Rockett, Kirk A; Williams, Thomas N

    2015-01-01

    Summary Background The global prevalence of X-linked glucose-6-phosphate dehydrogenase (G6PD) deficiency is thought to be a result of selection by malaria, but epidemiological studies have yielded confusing results. We investigated the relationships between G6PD deficiency and both malaria and non-malarial illnesses among children in Kenya. Methods We did this study in Kilifi County, Kenya, where the G6PD c.202T allele is the only significant cause of G6PD deficiency. We tested the associations between G6PD deficiency and severe and complicated Plasmodium falciparum malaria through a case-control study of 2220 case and 3940 control children. Cases were children aged younger than 14 years, who visited the high dependency ward of Kilifi County Hospital with severe malaria between March 1, 1998, and Feb 28, 2010. Controls were children aged between 3–12 months who were born within the same study area between August 2006, and September 2010. We assessed the association between G6PD deficiency and both uncomplicated malaria and other common diseases of childhood in a cohort study of 752 children aged younger than 10 years. Participants of this study were recruited from a representative sample of households within the Ngerenya and Chonyi areas of Kilifi County between Aug 1, 1998, and July 31, 2001. The primary outcome measure for the case-control study was the odds ratio for hospital admission with severe malaria (computed by logistic regression) while for the cohort study it was the incidence rate ratio for uncomplicated malaria and non-malaria illnesses (computed by Poisson regression), by G6PD deficiency category. Findings 2863 (73%) children in the control group versus 1643 (74%) in the case group had the G6PD normal genotype, 639 (16%) versus 306 (14%) were girls heterozygous for G6PD c.202T, and 438 (11%) versus 271 (12%) children were either homozygous girls or hemizygous boys. Compared with boys and girls without G6PD deficiency, we found significant

  7. Glucose-6-phosphate dehydrogenase deficiency and the risk of malaria and other diseases in children in Kenya: a case-control and a cohort study.

    PubMed

    Uyoga, Sophie; Ndila, Carolyne M; Macharia, Alex W; Nyutu, Gideon; Shah, Shivang; Peshu, Norbert; Clarke, Geraldine M; Kwiatkowski, Dominic P; Rockett, Kirk A; Williams, Thomas N

    2015-10-01

    The global prevalence of X-linked glucose-6-phosphate dehydrogenase (G6PD) deficiency is thought to be a result of selection by malaria, but epidemiological studies have yielded confusing results. We investigated the relationships between G6PD deficiency and both malaria and non-malarial illnesses among children in Kenya. We did this study in Kilifi County, Kenya, where the G6PD c.202T allele is the only significant cause of G6PD deficiency. We tested the associations between G6PD deficiency and severe and complicated Plasmodium falciparum malaria through a case-control study of 2220 case and 3940 control children. Cases were children aged younger than 14 years, who visited the high dependency ward of Kilifi County Hospital with severe malaria between March 1, 1998, and Feb 28, 2010. Controls were children aged between 3-12 months who were born within the same study area between August 2006, and September 2010. We assessed the association between G6PD deficiency and both uncomplicated malaria and other common diseases of childhood in a cohort study of 752 children aged younger than 10 years. Participants of this study were recruited from a representative sample of households within the Ngerenya and Chonyi areas of Kilifi County between Aug 1, 1998, and July 31, 2001. The primary outcome measure for the case-control study was the odds ratio for hospital admission with severe malaria (computed by logistic regression) while for the cohort study it was the incidence rate ratio for uncomplicated malaria and non-malaria illnesses (computed by Poisson regression), by G6PD deficiency category. 2863 (73%) children in the control group versus 1643 (74%) in the case group had the G6PD normal genotype, 639 (16%) versus 306 (14%) were girls heterozygous for G6PD c.202T, and 438 (11%) versus 271 (12%) children were either homozygous girls or hemizygous boys. Compared with boys and girls without G6PD deficiency, we found significant protection from severe malaria (odds ratio [OR

  8. Glucose-6-phosphate dehydrogenase and leptin are related to marbling differences among Limousin and Angus or Japanese Black x Angus steers.

    PubMed

    Bonnet, M; Faulconnier, Y; Leroux, C; Jurie, C; Cassar-Malek, I; Bauchart, D; Boulesteix, P; Pethick, D; Hocquette, J F; Chilliard, Y

    2007-11-01

    This work investigated the metabolic basis for the variability of carcass and i.m. adiposity in cattle. Our hypothesis was that the comparison of extreme breeds for adiposity might allow for the identification of some metabolic pathways determinant for carcass and i.m. adiposity. Thus, 23- to 28-mo-old steers of 3 breeds, 2 with high [Angus or Japanese Black x Angus (J. Black cross)] and 1 with low (Limousin) i.m. and carcass adiposity, were used to measure activities or mRNA levels, or both, of enzymes involved in de novo lipogenesis [acetyl-coA carboxylase, fatty acid synthase (FAS), glucose-6-phosphate dehydrogenase (G6PDH), malic enzyme], circulating triacylglycerol (TAG) uptake (lipoprotein lipase), and fatty acid esterification (glycerol-3-phosphate dehydrogenase), as well as the mRNA level of leptin, an adiposity-related factor. In a first study, enzyme activities were assayed in the s.c. adipose tissue (AT), the oxidative rectus abdominis, and the glycolytic semitendinosus muscles from steers finished for 6 mo. Compared with Angus or J. Black cross, Limousin steers had a 27% less (P = 0.003) rib fat thickness, and 23 and 29% less (P < or = 0.02) FAS and G6PDH activities in s.c. AT. In rectus abdominis and semitendinosus, the 75% less (P < 0.001) TAG content was concomitant with 50% less (P < 0.001) G6PDH activity. In a second study, enzyme activities plus mRNA levels were assayed in an oxido-glycolytic muscle, the longissimus thoracis (LT), in the i.m. AT dissected from LT, and in s.c. AT from the same Limousin steers and from Angus steers finished for 10 mo. Compared with Angus, the 50% less (P < 0.001) rib fat thickness in Limousin contrasted with the 1.1- to 5.8-fold greater (P < or = 0.02) mRNA levels or activities, or both, of acetyl-coA carboxylase, G6PDH, lipoprotein lipase, and glycerol-3-phosphate dehydrogenase in s.c. AT. Conversely, the 90% less (P < 0.001) TAG content in Limousin LT was concomitant to the 79 and 83% less (P < or = 0.002) G6PDH

  9. Evidence that adrenal hexose-6-phosphate dehydrogenase can effect microsomal P450 cytochrome steroidogenic enzymes.

    PubMed

    Foster, Christy A; Mick, Gail J; Wang, Xudong; McCormick, Kenneth

    2013-09-01

    The role of adrenal hexose-6-phosphate dehydrogenase in providing reducing equivalents to P450 cytochrome steroidogenic enzymes in the endoplasmic reticulum is uncertain. Hexose-6-phosphate dehydrogenase resides in the endoplasmic reticulum lumen and co-localizes with the bidirectional enzyme 11β-hydroxysteroid dehydrogenase 1. Hexose-6-phosphate dehydrogenase likely provides 11β-hydroxysteroid dehydrogenase 1 with NADPH electrons via channeling. Intracellularly, two compartmentalized reactions generate NADPH upon oxidation of glucose-6-phosphate: cytosolic glucose-6-phosphate dehydrogenase and microsomal hexose-6-phosphate dehydrogenase. Because some endoplasmic reticulum enzymes require an electron donor (NADPH), it is conceivable that hexose-6-phosphate dehydrogenase serves in this capacity for these pathways. Besides 11β-hydroxysteroid dehydrogenase 1, we examined whether hexose-6-phosphate dehydrogenase generates reduced pyridine nucleotide for pivotal adrenal microsomal P450 enzymes. 21-hydroxylase activity was increased with glucose-6-phosphate and, also, glucose and glucosamine-6-phosphate. The latter two substrates are only metabolized by hexose-6-phosphate dehydrogenase, indicating that requisite NADPH for 21-hydroxylase activity was not via glucose-6-phosphate dehydrogenase. Moreover, dihydroepiandrostenedione, a non-competitive inhibitor of glucose-6-phosphate dehydrogenase, but not hexose-6-phosphate dehydrogenase, did not curtail activation by glucose-6-phosphate. Finally, the most compelling observation was that the microsomal glucose-6-phosphate transport inhibitor, chlorogenic acid, blunted the activation by glucose-6-phosphate of both 21-hydroxylase and 17-hydroxylase indicating that luminal hexose-6-phosphate dehydrogenase can supply NADPH for these enzymes. Analogous kinetic observations were found with microsomal 17-hydroxylase. These findings indicate that hexose-6-phosphate dehydrogenase can be a source, but not exclusively so, of NADPH

  10. Alterations in Energy/Redox Metabolism Induced by Mitochondrial and Environmental Toxins: A Specific Role for Glucose-6-Phosphate-Dehydrogenase and the Pentose Phosphate Pathway in Paraquat Toxicity

    PubMed Central

    2015-01-01

    Parkinson’s disease (PD) is a multifactorial disorder with a complex etiology including genetic risk factors, environmental exposures, and aging. While energy failure and oxidative stress have largely been associated with the loss of dopaminergic cells in PD and the toxicity induced by mitochondrial/environmental toxins, very little is known regarding the alterations in energy metabolism associated with mitochondrial dysfunction and their causative role in cell death progression. In this study, we investigated the alterations in the energy/redox-metabolome in dopaminergic cells exposed to environmental/mitochondrial toxins (paraquat, rotenone, 1-methyl-4-phenylpyridinium [MPP+], and 6-hydroxydopamine [6-OHDA]) in order to identify common and/or different mechanisms of toxicity. A combined metabolomics approach using nuclear magnetic resonance (NMR) and direct-infusion electrospray ionization mass spectrometry (DI-ESI-MS) was used to identify unique metabolic profile changes in response to these neurotoxins. Paraquat exposure induced the most profound alterations in the pentose phosphate pathway (PPP) metabolome. 13C-glucose flux analysis corroborated that PPP metabolites such as glucose-6-phosphate, fructose-6-phosphate, glucono-1,5-lactone, and erythrose-4-phosphate were increased by paraquat treatment, which was paralleled by inhibition of glycolysis and the TCA cycle. Proteomic analysis also found an increase in the expression of glucose-6-phosphate dehydrogenase (G6PD), which supplies reducing equivalents by regenerating nicotinamide adenine dinucleotide phosphate (NADPH) levels. Overexpression of G6PD selectively increased paraquat toxicity, while its inhibition with 6-aminonicotinamide inhibited paraquat-induced oxidative stress and cell death. These results suggest that paraquat “hijacks” the PPP to increase NADPH reducing equivalents and stimulate paraquat redox cycling, oxidative stress, and cell death. Our study clearly demonstrates that alterations

  11. Alterations in energy/redox metabolism induced by mitochondrial and environmental toxins: a specific role for glucose-6-phosphate-dehydrogenase and the pentose phosphate pathway in paraquat toxicity.

    PubMed

    Lei, Shulei; Zavala-Flores, Laura; Garcia-Garcia, Aracely; Nandakumar, Renu; Huang, Yuting; Madayiputhiya, Nandakumar; Stanton, Robert C; Dodds, Eric D; Powers, Robert; Franco, Rodrigo

    2014-09-19

    Parkinson's disease (PD) is a multifactorial disorder with a complex etiology including genetic risk factors, environmental exposures, and aging. While energy failure and oxidative stress have largely been associated with the loss of dopaminergic cells in PD and the toxicity induced by mitochondrial/environmental toxins, very little is known regarding the alterations in energy metabolism associated with mitochondrial dysfunction and their causative role in cell death progression. In this study, we investigated the alterations in the energy/redox-metabolome in dopaminergic cells exposed to environmental/mitochondrial toxins (paraquat, rotenone, 1-methyl-4-phenylpyridinium [MPP+], and 6-hydroxydopamine [6-OHDA]) in order to identify common and/or different mechanisms of toxicity. A combined metabolomics approach using nuclear magnetic resonance (NMR) and direct-infusion electrospray ionization mass spectrometry (DI-ESI-MS) was used to identify unique metabolic profile changes in response to these neurotoxins. Paraquat exposure induced the most profound alterations in the pentose phosphate pathway (PPP) metabolome. 13C-glucose flux analysis corroborated that PPP metabolites such as glucose-6-phosphate, fructose-6-phosphate, glucono-1,5-lactone, and erythrose-4-phosphate were increased by paraquat treatment, which was paralleled by inhibition of glycolysis and the TCA cycle. Proteomic analysis also found an increase in the expression of glucose-6-phosphate dehydrogenase (G6PD), which supplies reducing equivalents by regenerating nicotinamide adenine dinucleotide phosphate (NADPH) levels. Overexpression of G6PD selectively increased paraquat toxicity, while its inhibition with 6-aminonicotinamide inhibited paraquat-induced oxidative stress and cell death. These results suggest that paraquat "hijacks" the PPP to increase NADPH reducing equivalents and stimulate paraquat redox cycling, oxidative stress, and cell death. Our study clearly demonstrates that alterations in

  12. Crystal Structures of An F420-Dependent Glucose-6-Phosphate Dehydrogenase Fgd1 Involved in the Activation of the Anti-Tb Drug Candidate Pa-824 Reveal the Basis of Coenzyme And Substrate Binding

    SciTech Connect

    Bashiri, G.; Squire, C.J.; Moreland, N.J.; Baker, E.N.

    2009-05-11

    The modified flavin coenzyme F{sub 420} is found in a restricted number of microorganisms. It is widely distributed in mycobacteria, however, where it is important in energy metabolism, and in Mycobacterium tuberculosis (Mtb) is implicated in redox processes related to non-replicating persistence. In Mtb, the F{sub 420}-dependent glucose-6-phosphate dehydrogenase FGD1 provides reduced F{sub 420} for the in vivo activation of the nitroimidazopyran prodrug PA-824, currently being developed for anti-tuberculosis therapy against both replicating and persistent bacteria. The structure of M. tuberculosis FGD1 has been determined by x-ray crystallography both in its apo state and in complex with F{sub 420} and citrate at resolutions of 1.90 and 1.95{angstrom}, respectively. The structure reveals a highly specific F{sub 420} binding mode, which is shared with several other F{sub 420}-dependent enzymes. Citrate occupies the substrate binding pocket adjacent to F{sub 420} and is shown to be a competitive inhibitor (IC{sub 50} 43 {micro}m). Modeling of the binding of the glucose 6-phosphate (G6P) substrate identifies a positively charged phosphate binding pocket and shows that G6P, like citrate, packs against the isoalloxazine moiety of F{sub 420} and helps promote a butterfly bend conformation that facilitates F{sub 420} reduction and catalysis.

  13. Silencing trehalose-6-phosphate synthase incapacitates adult mosquitoes by interfering with the biosynthetic pathway for flight fuel

    USDA-ARS?s Scientific Manuscript database

    Trehalose is a disaccharide comprised of two glucose molecules. It is the main blood sugar of insects and is essential for flight. Trehalose is synthesized by two enzymes: trehalose-6-phosphate synthase (T6PS) converts glucose-6-phosphate to trehalose-6-phosphate, and trehalose-6-phosphate phosphata...

  14. [Dynamics of erythrocyte hexokinase activity during glucose tolerance test in children with hereditary diabetes mellitus].

    PubMed

    Ignatiuk, T E; Ermolenko, R I

    1979-01-01

    In determining the changes in hexokinase activity in erythrocytes during the glucose tolerance test in children with heredity aggravated by diabetes mellitus in comparison with such in apparently healthy children it was shown that in latent diabets the enzyme activity failed to alter during the whold period of study (on fasting stomach, 30, 60 and 180 minutes after glucose load), and increased 60 minutes after glucose load in potential diabetes, but to a lesser extent than in the control group. Changes of erythrocyte hexokinase response to glucose administration could serve as an auxiliary criterion for determination of the degree of risk in children with threatening diabetes.

  15. Glucose and erythrocyte ATP: distinctive effects of dipyridamole and of ticlopidine.

    PubMed

    Solvay, H; Kahn, M; Garreyn, S; Cloarec, M; Sneppe, R; Schram, E; Fenollar, J V

    1987-11-01

    This experiment suggests the following points: 1. Erythrocytes in control patients and in atherosclerosis patients seem to have a variable grade of affinity for adenosine and for plasma glucose. This variable grade seems to fix the level of the adenosine triphosphate (ATP) reserves and induces the erythrocytes' deformability. 2. The drop in the level of ATP reserves that induces the poor deformability of the erythrocytes in atherosclerosis patients would appear to be caused by two consecutive shortages: first a shortage that seems to be related to a deficiency of erythrocyte adenosine as the ATP shortage disappears with dipyridamole treatment and then a shortage induced by the lack of erythrocyte glucose and suppressed by the addition of ticlopidine to the dipyridamole treatment.

  16. A dynamic and stationary rheological study of erythrocytes incubated in a glucose medium.

    PubMed

    Riquelme, Bibiana; Foresto, Patricia; D'Arrigo, Mabel; Valverde, Juana; Rasia, Rodolfo

    2005-02-28

    A higher than normal glucose concentration in a suspending medium may produce non-enzymatic glycosylation of erythrocyte proteins. This process can modify the viscoelastic properties of erythrocytes. In this paper, we studied the possible relationship between glucose concentration in a suspending medium and erythrocyte rheological parameters. Human venous blood was obtained from the antecubital veins of 10 healthy volunteers. Blood samples were anticoagulated with EDTA and centrifuged. Red blood cells (RBCs) were washed and subsequently divided in aliquots, which were incubated in vitro with glucose solutions of different concentrations. Dynamic and stationary viscoelastic parameters of RBCs were determined by laser diffractometry in an Erythrodeformeter. Aggregate shape parameter (ASP) of the RBCs was determined by digital image processing. Significant changes were observed both in ASP and in rheological parameters when the glucose concentration in the medium was increased, demonstrating that a glucose concentration as low as 1% induces alterations in the mechanical properties of RBCs.

  17. Purification and Characterization of Glucose 6-Phosphate Dehydrogenase, 6-Phosphogluconate Dehydrogenase, and Glutathione Reductase from Rat Heart and Inhibition Effects of Furosemide, Digoxin, and Dopamine on the Enzymes Activities.

    PubMed

    Adem, Sevki; Ciftci, Mehmet

    2016-06-01

    The present study was aimed to investigate characterization and purification of glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, and glutathione reductase from rat heart and the inhibitory effect of three drugs. The purification of the enzymes was performed using 2',5'-ADP sepharose 4B affinity material. The subunit and the natural molecular weights were analyzed by SDS-PAGE and gel filtration. Biochemical characteristics such as the optimum temperature, pH, stable pH, and salt concentration were examined for each enzyme. Types of product inhibition and Ki values with Km and Vmax values of the substrates and coenzymes were determined. According to the obtained Ki and IC50 values, furosemide, digoxin, and dopamine showed inhibitory effect on the enzyme activities at low millimolar concentrations in vitro conditions. Dopamine inhibited the activity of these enzymes as competitive, whereas furosemide and digoxin inhibited the activity of the enzyme as noncompetitive. © 2016 Wiley Periodicals, Inc.

  18. The effect of restricted hydration on the rate of reaction of glucose 6-phosphate dehydrogenase, phosphoglucose isomerase, hexokinase and fumarase. Relevance for metabolism in xeric (near-dry) conditions

    PubMed Central

    Stevens, Evelyn; Stevens, Lewis

    1979-01-01

    A method is described for the measurement of enzyme activity under xeric conditions. The reaction mixtures had water contents ranging between 0.1 and 0.6g/g of reaction mixture. For glucose 6-phosphate dehydrogenase, hexokinase and fumarase, enzyme activity became detectable (about 0.05% of the fully hydrated rate) when the water content was about 0.2g/g of reaction mixture, and for phosphoglucose isomerase, around 0.15g/g of reaction mixture. With the water content raised to 0.3g/g of reaction mixture the reaction rates were only increased to 0.1–3% of the fully hydrated rate. When the combined rates for phosphoglucose isomerase and glucose 6-phosphate dehydrogenase were measured, reasonable agreement was found between the experimental data and those calculated from the individual experimentally determined rates on the assumption that diffusion was not further limiting. A method was devised for measuring the diffusion coefficients of low-molecular-weight substances in solutions having low water contents. The diffusion coefficients of riboflavin in sorbitol solution decreased by about 100-fold when the water content of the latter was reduced from 3 to 0.25g/g of sorbitol. It is concluded that to detect enzyme activity a certain minimal amount of water is required and that above this minimum the rate is still restricted by diffusion limitation. The relevance of the results to the physical state of water in reaction mixtures and to metabolism in seeds and spores in xeric conditions is discussed. PMID:475753

  19. A survey for isoenzymes of glucosephosphate isomerase, phosphoglucomutase, glucose-6-phosphate dehydrogenase and 6-Phosphogluconate dehydrogenase in C3-, C 4-and crassulacean-acid-metabolism plants, and green algae.

    PubMed

    Herbert, M; Burkhard, C; Schnarrenberger, C

    1979-01-01

    Two isoenzymes each of glucosephosphate isomerase (EC 5.3.1.9), phosphoglucomutase (EC 2.7.5.1), glucose-6-phosphate dehydrogenase (EC 1.1.1.49) and 6-phosphogluconate dehydrogenase (EC 1.1.1.43) were separated by (NH4)2SO4 gradient solubilization and DEAE-cellulose ion-exchange chromatography from green leaves of the C3-plants spinach (Spinacia oleracea L.), tobacco (Nicotiana tabacum L.) and wheat (Triticum aestivum L.), of the Crassulacean-acid-metabolism plants Crassula lycopodioides Lam., Bryophyllum calycinum Salisb. and Sedum rubrotinctum R.T. Clausen, and from the green algae Chlorella vulgaris and Chlamydomonas reinhardii. After isolation of cell organelles from spinach leaves by isopyenic centrifugation in sucrose gradients one of two isoenzymes of each of the four enzymes was found to be associated with whole chloroplasts while the other was restricted to the soluble cell fraction, implying the same intracellular distribution of these isoenzymes also in the other species.Among C4-plants, glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were found in only one form in corn (Zea mays L.), sugar cane (Saccharum officinarum L.) and Coix lacrymajobi L., but as two isoenzymes in Atriplex spongiosa L. and Portulaca oleracea L. In corn, the two dehydrogenases were mainly associated with isolated mesophyll protoplasts while in Atriplex spongiosa they were of similar specific activity in both mesophyll protoplasts and bundle-sheath strands. In all five C4-plants three isoenzymes of glucosephosphate isomerase and phosphoglucomutase were found. In corn two were localized in the bundle-sheath strands and the third one in the mesophyll protoplasts. The amount of activity of the enzymes was similar in each of the two cell fractions. Apparently, C4 plants have isoenzymes not only in two cell compartments, but also in physiologically closely linked cell types such as mesophyll and bundle-sheath cells.

  20. Improved localization of glucose-6-phosphate dehydrogenase activity in cells with 5-cyano-2,3-ditolyl-tetrazolium chloride as fluorescent redox dye reveals its cell cycle-dependent regulation.

    PubMed

    Frederiks, Wilma M; van Marle, Jan; van Oven, Carel; Comin-Anduix, Begonya; Cascante, Marta

    2006-01-01

    Since the introduction of cyano-ditolyl-tetrazolium chloride (CTC), a tetrazolium salt that gives rise to a fluorescent formazan after reduction, it has been applied to quantify activity of dehydrogenases in individual cells using flow cytometry. Confocal laser scanning microscopy (CLSM) showed that the fluorescent formazan was exclusively localized at the surface of individual cells and not at intracellular sites of enzyme activity. In the present study, the technique has been optimized to localize activity of glucose-6-phosphate dehydrogenase (G6PD) intracellularly in individual cells. Activity was demonstrated in cultured fibrosarcoma cells in different stages of the cell cycle. Cells were incubated for the detection of G6PD activity using a medium containing 6% (w/v) polyvinyl alcohol, 5 mM CTC, magnesium chloride, sodium azide, the electron carrier methoxyphenazine methosulphate, NADP, and glucose-6-phosphate. Before incubation, cells were permeabilized with 0.025% glutaraldehyde. Fluorescent formazan was localized exclusively in the cytoplasm of fibrosarcoma cells. The amount of fluorescent formazan in cells increased linearly with incubation time when measured with flow cytometry and CLSM. When combining the Hoechst staining for DNA with the CTC method for the demonstration of G6PD activity, flow cytometry showed that G6PD activity of cells in S phase and G2/M phase is 27 +/- 4% and 43 +/- 4% higher, respectively, than that of cells in G1 phase. CLSM revealed that cells in all phases of mitosis as well as during apoptosis contained considerably lower G6PD activity than cells in interphase. It is concluded that posttranslational regulation of G6PD is responsible for this cell cycle-dependent activity.

  1. D-glucose-induced second harmonic generation response in human erythrocytes.

    PubMed

    Lev, Dmitry; Puzenko, Alexander; Manevitch, Alexandra; Manevitch, Zacharia; Livshits, Leonid; Feldman, Yuri; Lewis, Aaron

    2009-02-26

    The first experimental results of the nonresonant second harmonic generation (SHG) studies of human erythrocytes membrane exposed to various glucose concentrations in phosphate buffered saline (PBS solution) are presented in this article. It is shown that the SHG signal from the membrane can be altered as a function of glucose concentration. The link between the variation of the SHG intensity and the membrane dielectric permittivity with glucose is established both theoretically and experimentally by comparison with time domain dielectric spectroscopy (TDDS) measurement data.

  2. Triggering of Suicidal Erythrocyte Death by Penta-O-galloyl-β-d-glucose

    PubMed Central

    Alzoubi, Kousi; Honisch, Sabina; Abed, Majed; Lang, Florian

    2013-01-01

    The polyphenolic 1,2,3,4,6-penta-O-galloyl-beta-d-glucose from several medicinal herbs triggers apoptosis and has, thus, been proposed for treatment of malignancy. The substance is at least partially effective through caspase activation. In analogy to apoptosis of nucleated cells, erythrocytes may enter suicidal death or eryptosis, which is characterized by cell shrinkage and by phosphatidylserine translocation to the erythrocyte surface. Eryptosis is triggered by increase of cytosolic Ca2+-activity ([Ca2+]i). The sensitivity to [Ca2+]i is enhanced by ceramide. The present study explored whether penta-O-galloyl-β-d-glucose stimulates eryptosis. Cell volume was estimated from forward scatter, phosphatidylserine exposure from annexin V binding, hemolysis from hemoglobin-release, [Ca2+]i from Fluo3-fluorescence and ceramide abundance from fluorescent antibodies. A 48-h exposure of human erythrocytes to penta-O-galloyl-β-d-glucose significantly decreased forward scatter (50 µM) and significantly increased annexin V binding (10 µM). Up to 50 µM penta-O-galloyl-β-d-glucose did not significantly modify [Ca2+]i. However, the effect of penta-O-galloyl-β-d-glucose (25 µM) induced annexin V binding was slightly, but significantly, blunted by removal of extracellular Ca2+, pointing to sensitization of erythrocytes to the scrambling effect of Ca2+. Penta-O-galloyl-β-d-glucose (25 µM) further increased ceramide formation. In conclusion, penta-O-galloyl-β-d-glucose stimulates suicidal erythrocyte death or eryptosis, an effect partially due to stimulation of ceramide formation with subsequent sensitization of erythrocytes to Ca2+. PMID:24368324

  3. Regulation of glucose-6-phosphate dehydrogenase and malic enzyme in liver and adipose tissue: effect of dietary trilinolein level in starved-refed and ad libitum-fed rats.

    PubMed

    Nace, C S; Szepesi, B; Michaelis, O E

    1979-06-01

    The responses of glucose-6-phosphate dehydrogenase (G6PD) (EC 1.1.1.49) and malic enzyme (ME) (EC 1.1.1.40) were studied in liver and adipose tissue of rats fed for 2 days a high glucose diet containing levels of synthetic trilinolein ranging from 0 to 25% (w/w) of the diet (trilinolein was substituted for glucose). One group of rats was starved for 2 days before the trilinolein-containing diets were fed (starved-refed); a second group of rats was fed a fat-free diet for 7 days before the trilinolein-containing diets were fed (ad libitum). Liver G6PD activity decreased exponentially and liver ME activity decreased linearly with increasing dietary trilinolein in starved-refed rats, but did not decrease significantly in ad libitum fed rats. Total liver lipid decreased exponentially with increasing trilinolein in starved-refed rats, but increased exponentially in ad libitum fed rats. Adipose tissue G6PD and ME activities decreased slightly with increasing trilinolein in starved-refed rats, but did not decrease in ad libitum fed rats. When the data were adjusted by analysis of covariance for differences in glucose intake, the liver responses in starved-refed rats were still significant but the adipose tissue responses were not, indicating that the responses of adipose tissue (but not of liver) may have resulted from decreased glucose intake rather than from increased trilinolein intake. The results suggest that dietary trilinolein inhibits the characteristic increase in liver G6PD, ME and total lipids upon starvation-refeeding. However, after the levels of these parameters have been increased by feeding a fat-free diet they cannot be decreased by dietary trilinolein in 2 days.

  4. Dynamics of morphofunctional erythrocyte properties during intravenous glucose injection in patients with coronary heart disease

    NASA Astrophysics Data System (ADS)

    Malinova, Lidia I.; Simonenko, Georgy V.; Denisova, Tatyana P.; Tuchin, Valery V.

    2007-02-01

    Dynamics of glucose concentration in human organism is an important diagnostic characteristic for it's parameters correlate significantly with the severity of metabolic, vessel and perfusion disorders. 36 patients with stable angina pectoris of II and III functional classes were involved in this study. All of them were men in age range of 45-59 years old. 7 patients hospitalized with acute myocardial infarction (aged from 49 to 59 years old) form the group of compare. Control group (n = 5) was of practically healthy men in comparable age. To all patients intravenous glucose solution (40%) in standard loading dose was injected. Capillary and vein blood samples were withdrawn before, and 5, 60, 120, 180 and 240 minutes after glucose load. At these time points blood pressure and glucose concentration were measured. In prepared blood smears shape, deformability and sizes of erythrocytes, quantity and degree of shear stress resistant erythrocyte aggregates were studied. Received data were approximated by polynomial of high degree to receive concentration function of studied parameters, which first derivative elucidate velocity characteristics of morphofunctional erythrocyte properties during intravenous glucose injection in patients with coronary heart disease and practically healthy persons. Received data show principle differences in dynamics of morphofunctional erythrocyte properties during intravenous glucose injection in patients with coronary heart disease as a possible mechanism of coronary blood flow destabilization.

  5. Post-Translational Regulation of the Glucose-6-Phosphatase Complex by Cyclic Adenosine Monophosphate Is a Crucial Determinant of Endogenous Glucose Production and Is Controlled by the Glucose-6-Phosphate Transporter.

    PubMed

    Soty, Maud; Chilloux, Julien; Delalande, François; Zitoun, Carine; Bertile, Fabrice; Mithieux, Gilles; Gautier-Stein, Amandine

    2016-04-01

    The excessive endogenous glucose production (EGP) induced by glucagon participates in the development of type 2 diabetes. To further understand this hormonal control, we studied the short-term regulation by cyclic adenosine monophosphate (cAMP) of the glucose-6-phosphatase (G6Pase) enzyme, which catalyzes the last reaction of EGP. In gluconeogenic cell models, a 1-h treatment by the adenylate cyclase activator forskolin increased G6Pase activity and glucose production independently of any change in enzyme protein amount or G6P content. Using specific inhibitors or protein overexpression, we showed that the stimulation of G6Pase activity involved the protein kinase A (PKA). Results of site-directed mutagenesis, mass spectrometry analyses, and in vitro phosphorylation experiments suggested that the PKA stimulation of G6Pase activity did not depend on a direct phosphorylation of the enzyme. However, the temperature-dependent induction of both G6Pase activity and glucose release suggested a membrane-based mechanism. G6Pase is composed of a G6P transporter (G6PT) and a catalytic unit (G6PC). Surprisingly, we demonstrated that the increase in G6PT activity was required for the stimulation of G6Pase activity by forskolin. Our data demonstrate the existence of a post-translational mechanism that regulates G6Pase activity and reveal the key role of G6PT in the hormonal regulation of G6Pase activity and of EGP.

  6. Derivativation of the human erythrocyte glucose transporter using a novel forskolin photoaffinity label

    SciTech Connect

    Wadzinski, B.; Shanahan, M.; Ruoho, A.

    1987-05-01

    An iodinated photoaffinity label for the glucose transporter, 3-iodo-4-azidophenethylamido-7-0-succinyldeacetyl-forskolin (IAPS-Fsk), has been synthesized, purified, and characterized. The K/sub i/ for inhibition of 3-0-methylglucose transport by TAPS-Fsk in human erythrocytes was found to be 0.1 uM. The carrier-free radioiodinated label has been shown to be a highly specific photoaffinity label for the human erythrocyte glucose transporter. Photolysis of erythrocyte membranes with 1-10 nM (I-125)IAPS-Fsk and analysis by SDS-PAGE showed specific derivatization of a broad band with an apparent molecular weight of 40-70 kDa. Photoincorporation using 2 nM (I-125)IAPS-Fsk was protected with D-glucose, cytochalasin B, and forskolin. No protection was observed with L-glucose. Endo-B-galactosidase digestion and trypsinization of (I-125)IAPS-Fsk labelled erythrocytes reduced the specifically radiolabelled transporter to 40 kDa and 18 kDa respectively. (I-125)-IAPS-Fsk will be used to study the structural aspects of the glucose transporter.

  7. Life and Death of Glucose-6-Phosphate Dehydrogenase (G6PD) Deficient Erythrocytes - Role of Redox Stress and Band 3 Modifications.

    PubMed

    Arese, Paolo; Gallo, Valentina; Pantaleo, Antonella; Turrini, Franco

    2012-10-01

    G6PD catalyzes the first, pace-making reaction of pentosephosphate cycle (PPC) which produces NADPH. NADPH maintains glutathione and thiol groups of proteins and enzymes in the reduced state which is essential for protection against oxidative stress. Individuals affected by G6PD deficiency are unable to regenerate reduced glutathione (GSH) and are undefended against oxidative stress. G6PD deficiency accelerates normal senescence and enhances the precocious removal of chronologically young, yet biologically old cells. The term hemolytic anemia is misleading because RBCs do not lyse but are removed by phagocytosis. Acute hemolysis by fava bean ingestion in G6PD deficient individuals (favism) is described being the best-studied natural model of oxidant damage. It bears strong analogies to hemolysis by oxidant drugs or chemicals. Membrane alterations observed in vivo during favism are superimposable to changes in senescent RBCs. In summary, RBC membranes isolated from favic patients contained elevated amounts of complexes between IgG and the complement fragment C3b/C3c and were prone to vesiculation. Anti-band 3 IgG reacted to aggregated band 3-complement complexes. In favism extensive clustering of band 3 and membrane deposition of hemichromes were also observed. Severely damaged RBCs isolated from early crises had extensive membrane cross-bonding and very low GSH levels and were phagocytosed 10-fold more intensely compared to normal RBCs.

  8. Life and Death of Glucose-6-Phosphate Dehydrogenase (G6PD) Deficient Erythrocytes – Role of Redox Stress and Band 3 Modifications

    PubMed Central

    Arese, Paolo; Gallo, Valentina; Pantaleo, Antonella; Turrini, Franco

    2012-01-01

    Summary G6PD catalyzes the first, pace-making reaction of pentosephosphate cycle (PPC) which produces NADPH. NADPH maintains glutathione and thiol groups of proteins and enzymes in the reduced state which is essential for protection against oxidative stress. Individuals affected by G6PD deficiency are unable to regenerate reduced glutathione (GSH) and are undefended against oxidative stress. G6PD deficiency accelerates normal senescence and enhances the precocious removal of chronologically young, yet biologically old cells. The term hemolytic anemia is misleading because RBCs do not lyse but are removed by phagocytosis. Acute hemolysis by fava bean ingestion in G6PD deficient individuals (favism) is described being the best-studied natural model of oxidant damage. It bears strong analogies to hemolysis by oxidant drugs or chemicals. Membrane alterations observed in vivo during favism are superimposable to changes in senescent RBCs. In summary, RBC membranes isolated from favic patients contained elevated amounts of complexes between IgG and the complement fragment C3b/C3c and were prone to vesiculation. Anti-band 3 IgG reacted to aggregated band 3-complement complexes. In favism extensive clustering of band 3 and membrane deposition of hemichromes were also observed. Severely damaged RBCs isolated from early crises had extensive membrane cross-bonding and very low GSH levels and were phagocytosed 10-fold more intensely compared to normal RBCs. PMID:23801924

  9. Effect of glucose concentration on formation of AGEs in erythrocytes in vitro.

    PubMed

    Nagai, Ryoji; Deemer, Elizabeth K; Brock, Jonathan W; Thorpe, Suzanne R; Baynes, John W

    2005-06-01

    Posttranslational modifications, such as advanced glycoxidation and lipoxidation end products (AGE/ALEs), are implicated in the pathogenesis of diabetic complications and atherosclerosis. Recent studies have demonstrated that AGE/ALEs are generated not only in extracellular matrix proteins, but also in intracellular proteins from metabolic intermediates. In this study we investigate the effect of glucose concentration on the formation of the AGE/ALEs, Nepsilon-(carboxymethyl)lysine (CML), Nepsilon-(carboxyethyl)lysine (CEL), S-(carboxymethyl)cysteine (CMC), and S-(2-succinyl)cysteine (2SC) in erythrocytes as a function of glucose concentration. Human erythrocytes (10% hematocrit) were incubated in Dulbecco's modified Eagle's medium (DMEM) containing 5 mM or 30 mM glucose for 5 days at 37 degrees C. Globin was recovered by precipitation with 0.25 M HCl in acetone. Following acid hydrolysis, amino acids were converted to their trifluoroacetyl methyl ester derivatives and analyzed by GC/MS/MS. The CML and CEL content of globin increased in a time- and glucose-dependent manner and also increased 1.3- and 1.8-fold, respectively, in incubations containing 30 mM glucose; whereas CMC and 2SC content did not change during the five-day incubations. Furthermore, CEL content of globin in erythrocytes incubated with 30 mM was the highest in the other AGEs, indicating that methylglyoxal may play a major role in AGE formation in erythrocytes. The erythrocyte system should be useful for cellular screening of the efficacy of inhibitors of AGE/ALE formation.

  10. Effects of test spills of chemically dispersed and nondispersed oil on the activity of aspartate aminotransferase and glucose-6-phosphate dehydrogenase in two intertidal bivalves, Mya arenaria and Mytilus edulis

    SciTech Connect

    Gilfillan, E.S.; Foster, J.; Gerber, R.; Hanson, S.A.; Page, D.S.; Vallas, D.

    1982-10-01

    In 1981, two test oil spills were made in Maine. One spill was 975 L (250 gal) of Murban crude oil; the other was 975 L of Murban crude oil premixed with 97 L (25 gal) of Corexit 9527. The uptake of the oil and its effects on enzymatic activity in two species of common intertidal bivalve mollusks, Mya arenaria and Mytilus edulis, were studied. Data were obtained on uptake and depuration of the oil for each species; data were also obtained on the activity of glucose-6-phosphate dehydrogenase and aspartate aminotransferase for each species. Data were collected both before and after each of the spills. Much less oil was taken up by the populations of animals exposed to chemically dispersed oil than by those exposed to nondispersed oil. Rates of depuration were the same for each species; they were also the same regardless of oil exposure. Significant long-term effects on enzyme activity were detected only in those animals exposed to nondispersed oil.

  11. Glycogen storage disease type 1b: an early onset severe phenotype associated with a novel mutation (IVS4) in the glucose 6-phosphate translocase (SLC37A4) gene in a Turkish patient.

    PubMed

    Oguz, M M; Aykan, E; Yilmaz, G; Aytekin, C; Karaer, K; Açoğlu, E A

    2014-01-01

    Glycogen storage disease type I (GSD-I) is a group of autosomal recessive disorders that include types Ia and Ib. GSD-Ib is caused by a deficiency in the glucose-6-phosphate transporter (G6PT) caused by a mutation in the SLC37A4 gene coding for G6PT. Glycogen storage disease is characterized by poor tolerance to fasting, growth retardation and hepatomegaly resulting from accumulation of glycogen and fat in the liver and chronic neutropenia. Herein we describe a 4-month-old Turkish patient with early onset and severe typical clinical features of GSD-1b in which a novel mutation in the SLC37A4 gene was detected. After the bone marrow examination parenteral antibiotic therapy and subcutaneous granulocyte colony-stimulating factor (G-CSF) were started. Due to the severe neutropenia the patient had developed nosocomial sepsis and the dose of G-CSF was increased. After 2 months later from the initial treatment of the G-CSF he developed splenomegaly and urinary complications. Despite maximal therapy he had an extremely poor quality of life and life-threatening complications due to impaired bone marrow function. As the patient required continual hospitalization he was schedule for bone marrow transplantation.

  12. cDNA cloning of glucose-6-phosphate isomerase from crucian carp (Carassius carassius) and expression of the active region as myofibril-bound serine proteinase inhibitor in Escherichia coli.

    PubMed

    Han, Long; Cao, Min-Jie; Shi, Chao-lan; Wei, Xiao-Nan; Li, Huan; Du, Cui-Hong

    2014-02-01

    Glucose-6-phosphate isomerase (GPI) (EC 5.3.1.9) can act as a myofibril-bound serine proteinase (MBSP) inhibitor (MBSPI) in fish. In order to better understand the biological information of the GPI and its functional domain for inhibiting MBSP, the cDNA of GPI was cloned from crucian carp (Carassius carassius) with RT-PCR, nested-PCR and 3'-RACE. The result of sequencing showed that the GPI cDNA had an open reading frame of 1662bp encoding 553 amino acid residues. After constructing and comparing the three-dimensional structures of GPI and MBSP, the middle fragment of crucian carp GPI (GPI-M) was predicted as a functional domain for inhibiting MBSP. Then the crucian carp GPI-M gene was cloned and expressed in Escherichia coli. SDS-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the recombinant GPI-M (rGPI-M) with molecular mass of approximately 21kDa in the form of inclusion bodies. The rGPI-M was obtained at an electrophoresis level purity of approximately 95% after denaturation and dialysis renaturation.

  13. Impairment of erythrocytes incubated in glucose medium: a wavelet-information theory analysis.

    PubMed

    Korol, A M; Rosso, O A; Martín, M T; D'Arrigo, M; Riquelme, B D

    2011-07-01

    This study investigates the effects produced by an increased concentration of glucose in a suspending medium on the erythrocytes Information Theory quantifiers. Erythrocytes, which were obtained from eight healthy volunteers, were washed and incubated in vitro with glucose solutions at different concentrations. The measured Wavelet-based Information Theory quantifiers include the Relative Wavelet Energy (RWE), the Normalized Total Wavelet Shannon Entropy (NTWS), MPR-Statistical Complexity Measure (SCM) and entropy-complexity plane. The results show that the increase in glucose concentration does not produce significant changes on the RWE, while significant ones on the NTSE, which combined with SCM values allow to identify different behaviour for all the different populations in the entropy-complexity plane. Modification in the hemorheological properties of cells could be clearly detected with these Wavelet-based Information Theory quantifiers.

  14. Dielectric spectroscopy study of specific glucose influence on human erythrocyte membranes

    NASA Astrophysics Data System (ADS)

    Hayashi, Yoshihito; Livshits, Leonid; Caduff, Andreas; Feldman, Yuri

    2003-02-01

    Time domain dielectric spectroscopy has been used to study spherical erythrocytes, suspended in diluted phosphate buffered saline (PBS) buffers at varying concentrations of D- and L-glucose at 25°C. The osmolarity for each glucose solution was adapted, equalling that of a 63% PBS (183 mOsm). The strong effect of the electrode polarization was corrected using the fractal approach in time domain. For analysis of the dielectric properties of suspensions of erythrocytes, the Maxwell-Wagner model is used for small volume fractions. Values of the permittivity and conductivity of the cell membrane were obtained from a fitting procedure according to the one-shell model. The non-monotonic and specific response of membrane electric properties on D-glucose concentrations were observed, with a dramatic decrease around 12 mM. No changes of membrane properties have been observed in the presence of increasing concentrations of L-glucose, the biologically inactive enantiomer of D-glucose. The effect is thus specific to D-glucose. The possible mechanism of specific cell reaction to D-glucose is discussed in this paper.

  15. Evidence that forskolin binds to the glucose transporter of human erythrocytes

    SciTech Connect

    Lavis, V.R.; Lee, D.P.; Shenolikar, S.

    1987-10-25

    Binding of (4-/sup 3/H)cytochalasin B and (12-/sup 3/H)forskolin to human erythrocyte membranes was measured by a centrifugation method. Glucose-displaceable binding of cytochalasin B was saturable, with KD = 0.11 microM, and maximum binding approximately 550 pmol/mg of protein. Forskolin inhibited the glucose-displaceable binding of cytochalasin B in an apparently competitive manner, with K1 = 3 microM. Glucose-displaceable binding of (12-/sup 3/H)forskolin was also saturable, with KD = 2.6 microM and maximum binding approximately equal to 400 pmol/mg of protein. The following compounds inhibited binding of (12-/sup 3/H)forskolin and (4-/sup 3/H)cytochalasin B equivalently, with relative potencies parallel to their reported affinities for the glucose transport system: cytochalasins A and D, dihydrocytochalasin B, L-rhamnose, L-glucose, D-galactose, D-mannose, D-glucose, 2-deoxy-D-glucose, 3-O-methyl-D-glucose, phloretin, and phlorizin. A water-soluble derivative of forskolin, 7-hemisuccinyl-7-desacetylforskolin, displaced equivalent amounts of (4-/sup 3/H)cytochalasin B or (12-/sup 3/H)forskolin. Rabbit erythrocyte membranes, which are deficient in glucose transporter, did not bind either (4-/sup 3/H)cytochalasin B or (12-/sup 3/H)forskolin in a glucose-displaceable manner. These results indicate that forskolin, in concentrations routinely employed for stimulation of adenylate cyclase, binds to the glucose transporter. Endogenous ligands with similar specificities could be important modulators of cellular metabolism.

  16. Acquired hemoglobin variants and exposure to glucose-6-phosphate dehydrogenase deficient red blood cell units during exchange transfusion for sickle cell disease in a patient requiring antigen-matched blood.

    PubMed

    Raciti, Patricia M; Francis, Richard O; Spitalnik, Patrice F; Schwartz, Joseph; Jhang, Jeffrey S

    2013-08-01

    Red blood cell exchange (RBCEx) is frequently used in the management of patients with sickle cell disease (SCD) and acute chest syndrome or stroke, or to maintain target hemoglobin S (HbS) levels. In these settings, RBCEx is a category I or II recommendation according to guidelines on the use of therapeutic apheresis published by the American Society for Apheresis. Matching donor red blood cells (RBCs) to recipient phenotypes (e.g., C, E, K-antigen negative) can decrease the risk of alloimmunization in patients with multi-transfused SCD. However, this may select for donors with a higher prevalence of RBC disorders for which screening is not performed. This report describes a patient with SCD treated with RBCEx using five units negative for C, E, K, Fya, Fyb (prospectively matched), four of which were from donors with hemoglobin variants and/or glucose-6-phosphate dehydrogenase (G6PD) deficiency. Pre-RBCEx HbS quantification by high performance liquid chromatography (HPLC) demonstrated 49.3% HbS and 2.8% hemoglobin C, presumably from transfusion of a hemoglobin C-containing RBC unit during a previous RBCEx. Post-RBCEx HPLC showed the appearance of hemoglobin G-Philadelphia. Two units were G6PD-deficient. The patient did well, but the consequences of transfusing RBC units that are G6PD-deficient and contain hemoglobin variants are unknown. Additional studies are needed to investigate effects on storage, in-vivo RBC recovery and survival, and physiological effects following transfusion of these units. Post-RBCEx HPLC can monitor RBCEx efficiency and detect the presence of abnormal transfused units.

  17. Chronic nonspherocytic hemolytic anemia due to glucose-6-phosphate dehydrogenase deficiency: report of two families with novel mutations causing G6PD Bangkok and G6PD Bangkok Noi.

    PubMed

    Tanphaichitr, Voravarn S; Hirono, Akira; Pung-amritt, Parichat; Treesucon, Ajjima; Wanachiwanawin, Wanchai

    2011-07-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common hereditary enzymopathies worldwide. Mostly G6PD deficient cases are asymptomatic though they may have the risk of neonatal jaundice (NNJ) and acute intravascular hemolysis during oxidative stress. Chronic nonspherocytic hemolytic anemia (CNSHA) due to G6PD deficiency is rare. In Thailand, one case was reported 40 years ago and by biochemical study this G6PD was reported to be a new variant G6PD Bangkok. We, herein, report two families with CNSHA due to G6PD deficiency. In the first family, we have been following up the clinical course of the patient with G6PD Bangkok. In addition to chronic hemolysis, he had three acute hemolytic episodes requiring blood transfusions during childhood period. Multiple gallstones were detected at the age of 27. His two daughters who inherited G6PD Bangkok from him and G6PD Vanua Lava from his wife are asymptomatic. Both of them had NNJ and persistent evidences of compensated hemolysis. Molecular analysis revealed a novel missense mutation 825 G→C predicting 275 Lys→Asn causing G6PD Bangkok. In the second family, two male siblings are affected. They had NNJ and several hemolytic episodes which required blood transfusions. On follow-up they have been diagnosed with chronic hemolysis as evidenced by reticulocytosis and indirect hyperbilirubinemia. Molecular analysis revealed combined missense mutations in exons 12 and 13. The first mutation was 1376 G→T predicting 459 Arg→Leu (known as G6PD Canton) and the second one was 1502 T→G predicting 501 Phe→Cys. We designated the resulting novel G6PD variant, G6PD Bangkok Noi.

  18. Comparison of anti-mutated citrullinated vimentin, anti-cyclic citrullinated peptides, anti-glucose-6-phosphate isomerase and anti-keratin antibodies and rheumatoid factor in the diagnosis of rheumatoid arthritis in Chinese patients.

    PubMed

    Zhu, Tao; Feng, Liyun

    2013-04-01

    To evaluate the diagnostic value of anti-mutated citrullinated vimentin antibodies (anti-MCV), anti-cyclic citrullinated peptides antibodies (anti-CCP), anti-glucose-6-phosphate isomerase antibodies (anti-GPI) and anti-keratin antibodies (AKA) and rheumatoid factor (RF) in rheumatoid arthritis (RA). The five auto-antibodies were detected in serum samples of 56 patients with RA, 21 patients with systemic lupus erythematosus (SLE), 11 with ankylosing spondylitis (AS), six with Sjögren's syndrome (SS), four with connective tissue disease (CTD) and 20 healthy controls. Anti-MCV, anti-CCP and anti-GPI were detected by enzyme-linked immunosorbent assays (ELISA), AKA was determined by indirect immunofluorescence and RF was determined by rate nephelometry. In RA, anti-MCV and anti-GPI had the highest sensitivity (78.6% and 75.0%, respectively), anti-CCP and AKA had the highest specificity (97.6%). Anti-GPI had the lowest specificity (64.3%), and AKA had the lowest sensitivity (48.2%). When two antibodies were detected together, the sensitivity of anti-MCV/anti-CCP/RF were highest (92.9%) with a lower specificity (73.8%). The combination of anti-MCV/anti-CCP had a slightly decreased sensitivity (89.3%) and the same specificity (73.8%). The combination RF/anti-MCV/anti-CCP or anti-MCV/anti-CCP are usefully serologic tests for the diagnosis of RA in Chinese patients. © 2013 The Authors International Journal of Rheumatic Diseases © 2013 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

  19. Noninferiority of glucose-6-phosphate dehydrogenase deficiency diagnosis by a point-of-care rapid test vs the laboratory fluorescent spot test demonstrated by copper inhibition in normal human red blood cells.

    PubMed

    Baird, J Kevin; Dewi, Mewahyu; Subekti, Decy; Elyazar, Iqbal; Satyagraha, Ari W

    2015-06-01

    Tens of millions of patients diagnosed with vivax malaria cannot safely receive primaquine therapy against repeated attacks caused by activation of dormant liver stages called hypnozoites. Most of these patients lack access to screening for glucose-6-phosphate dehydrogenase (G6PD) deficiency, a highly prevalent disorder causing serious acute hemolytic anemia with primaquine therapy. We optimized CuCl inhibition of G6PD in normal red blood cells (RBCs) to assess G6PD diagnostic technologies suited to point of care in the impoverished rural tropics. The most widely applied technology for G6PD screening-the fluorescent spot test (FST)-is impractical in that setting. We evaluated a new point-of-care G6PD screening kit (CareStart G6PD, CSG) against FST using graded CuCl treatments to simulate variable hemizygous states, and varying proportions of CuCl-treated RBC suspensions to simulate variable heterozygous states of G6PD deficiency. In experiments double-blinded to CuCl treatment, technicians reading FST and CSG test (n = 269) classified results as positive or negative for deficiency. At G6PD activity ≤40% of normal (n = 112), CSG test was not inferior to FST in detecting G6PD deficiency (P = 0.003), with 96% vs 90% (P = 0.19) sensitivity and 75% and 87% (P = 0.01) specificity, respectively. The CSG test costs less, requires no specialized equipment, laboratory skills, or cold chain for successful application, and performs as well as the FST standard of care for G6PD screening. Such a device may vastly expand access to primaquine therapy and aid in mitigating the very substantial burden of morbidity and mortality imposed by the hypnozoite reservoir of vivax malaria.

  20. Hemolytic Potential of Tafenoquine in Female Volunteers Heterozygous for Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency (G6PD Mahidol Variant) versus G6PD-Normal Volunteers.

    PubMed

    Rueangweerayut, Ronnatrai; Bancone, Germana; Harrell, Emma J; Beelen, Andrew P; Kongpatanakul, Supornchai; Möhrle, Jörg J; Rousell, Vicki; Mohamed, Khadeeja; Qureshi, Ammar; Narayan, Sushma; Yubon, Nushara; Miller, Ann; Nosten, François H; Luzzatto, Lucio; Duparc, Stephan; Kleim, Jörg-Peter; Green, Justin A

    2017-07-24

    Tafenoquine is an 8-aminoquinoline under investigation for the prevention of relapse in Plasmodium vivax malaria. This open-label, dose-escalation study assessed quantitatively the hemolytic risk with tafenoquine in female healthy volunteers heterozygous for the Mahidol(487A) glucose-6-phosphate dehydrogenase (G6PD)-deficient variant versus G6PD-normal females, and with reference to primaquine. Six G6PD-heterozygous subjects (G6PD enzyme activity 40-60% of normal) and six G6PD-normal subjects per treatment group received single-dose tafenoquine (100, 200, or 300 mg) or primaquine (15 mg × 14 days). All participants had pretreatment hemoglobin levels ≥ 12.0 g/dL. Tafenoquine dose escalation stopped when hemoglobin decreased by ≥ 2.5 g/dL (or hematocrit decline ≥ 7.5%) versus pretreatment values in ≥ 3/6 subjects. A dose-response was evident in G6PD-heterozygous subjects (N = 15) receiving tafenoquine for the maximum decrease in hemoglobin versus pretreatment values. Hemoglobin declines were similar for tafenoquine 300 mg (-2.65 to -2.95 g/dL [N = 3]) and primaquine (-1.25 to -3.0 g/dL [N = 5]). Two further cohorts of G6PD-heterozygous subjects with G6PD enzyme levels 61-80% (N = 2) and > 80% (N = 5) of the site median normal received tafenoquine 200 mg; hemolysis was less pronounced at higher G6PD enzyme activities. Tafenoquine hemolytic potential was dose dependent, and hemolysis was greater in G6PD-heterozygous females with lower G6PD enzyme activity levels. Single-dose tafenoquine 300 mg did not appear to increase the severity of hemolysis versus primaquine 15 mg × 14 days.

  1. Purification of rat kidney glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, and glutathione reductase enzymes using 2',5'-ADP Sepharose 4B affinity in a single chromatography step.

    PubMed

    Adem, Sevki; Ciftci, Mehmet

    2012-01-01

    The enzymes of glucose 6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), and glutathione reductase (GR) were purified from rat kidney in one chromatographic step consisting of the use of the 2',5'-ADP Sepharose 4B by using different elution buffers. This purification procedure was accomplished with the preparation of the homogenate and affinity chromatography on 2',5'-ADP Sepharose 4B. The purity and subunit molecular weights of the enzymes were checked on SDS-PAGE and purified enzymes showed a single band on the gel. The native molecular weights of the enzymes were found with Sephadex G-150 gel filtration chromatography. Using this procedure, G6PG, having the specific activity of 32 EU/mg protein, was purified 531-fold with a yield of 88%; 6PGD, having the specific activity of 25 EU/mg protein, was purified 494-fold with a yield of 73%; and GR, having the specific activity of 33 EU/mg protein, was purified 477-fold with a yield of 76%. Their native molecular masses were estimated to be 144 kDa for G6PD, 110 kDa for 6PGD, and 121 kDa for GR and the subunit molecular weights were found to be 68, 56, and 61 kDa, respectively. A new modified method to purify G6PD, 6PGD, and GR, namely one chromatographic step using the 2',5'-ADP Sepharose 4B, is described for the first time in this study. This procedure has several advantages for purification of enzymes, such as, rapid purification, produces high yield, and uses less chemical materials.

  2. Photoaffinity labeling of the human erythrocyte glucose transporter with /sup 4/H-labelled forskolin

    SciTech Connect

    Shanahan, M.F.; Edwards, B.M.; Morris, D.P.

    1986-05-01

    Forskolin, a potent activator of adenylate cyclase, is also known to inhibit glucose transport in a number of cells. The authors have investigated photoincorporation of (/sup 3/H)forskolin into erythrocyte membrane proteins using a technique they previously developed for photolabeling the erythrocyte glucose transporter with cytochalasin B (CB). A 30-40s irradiation of erythrocyte ghosts in the presence of (/sup 3/H)forskolin resulted in a concentration-dependent, covalent incorporation of radiolabel into all of the major membrane protein bands. However, most of the incorporation occurred in only three regions of the gel. Peak 1 was a sharp peak near the top of the gel in the region corresponding to spectrin, peak 2 appeared to be associated with band 3 (approx. 90kDa), and the third region labeled was between 41-60 kDa which corresponds to the region of the glucose transporter. This region appeared to contain several overlapping peaks with the largest incorporation of label occurring around 45 kDa in the area of red cell actin. When photolabeling was performed in the presence of 400 ..mu..M cytochalasin B (8.0 ..mu..M forskolin) the labeling in the 41-60 kDa region was totally inhibited while labeling of the 90 kDa peak was partially blocked. CB had no effect on the photolabeling of peak 1 by forskolin.

  3. Effects of Red Wine Tannat on Oxidative Stress Induced by Glucose and Fructose in Erythrocytes in Vitro

    PubMed Central

    Pazzini, Camila Eliza Fernandes; Colpo, Ana Ceolin; Poetini, Márcia Rósula; Pires, Cauê Ferreira; de Camargo, Vanessa Brum; Mendez, Andreas Sebastian Loureiro; Azevedo, Miriane Lucas; Soares, Júlio César Mendes; Folmer, Vanderlei

    2015-01-01

    The literature indicates that red wine presents in its composition several substances that are beneficial to health. This study has investigated the antioxidant effects of Tannat red wine on oxidative stress induced by glucose and fructose in erythrocytes in vitro, with the purpose to determine some of its majoritarian phenolic compounds and its antioxidant capacity. Erythrocytes were incubated using different concentrations of glucose and fructose in the presence or absence of wine. From these erythrocytes were determined the production of thiobarbituric acid reactive species (TBARS), glucose consumption, and osmotic fragility. Moreover, quantification of total phenolic, gallic acid, caffeic acid, epicatechin, resveratrol, and DPPH scavenging activity in wine were also assessed. Red wine showed high levels of polyphenols analyzed, as well as high antioxidant potential. Erythrocytes incubated with glucose and fructose had an increase in lipid peroxidation and this was prevented by the addition of wine. The wine increased glucose uptake into erythrocytes and was able to decrease the osmotic fragility of erythrocytes incubated with fructose. Altogether, these results suggest that wine leads to a reduction of the oxidative stress induced by high concentrations of glucose and fructose. PMID:26078708

  4. Effects of Red Wine Tannat on Oxidative Stress Induced by Glucose and Fructose in Erythrocytes in Vitro.

    PubMed

    Pazzini, Camila Eliza Fernandes; Colpo, Ana Ceolin; Poetini, Márcia Rósula; Pires, Cauê Ferreira; de Camargo, Vanessa Brum; Mendez, Andreas Sebastian Loureiro; Azevedo, Miriane Lucas; Soares, Júlio César Mendes; Folmer, Vanderlei

    2015-01-01

    The literature indicates that red wine presents in its composition several substances that are beneficial to health. This study has investigated the antioxidant effects of Tannat red wine on oxidative stress induced by glucose and fructose in erythrocytes in vitro, with the purpose to determine some of its majoritarian phenolic compounds and its antioxidant capacity. Erythrocytes were incubated using different concentrations of glucose and fructose in the presence or absence of wine. From these erythrocytes were determined the production of thiobarbituric acid reactive species (TBARS), glucose consumption, and osmotic fragility. Moreover, quantification of total phenolic, gallic acid, caffeic acid, epicatechin, resveratrol, and DPPH scavenging activity in wine were also assessed. Red wine showed high levels of polyphenols analyzed, as well as high antioxidant potential. Erythrocytes incubated with glucose and fructose had an increase in lipid peroxidation and this was prevented by the addition of wine. The wine increased glucose uptake into erythrocytes and was able to decrease the osmotic fragility of erythrocytes incubated with fructose. Altogether, these results suggest that wine leads to a reduction of the oxidative stress induced by high concentrations of glucose and fructose.

  5. Tryptic digestion of the human erythrocyte glucose transporter: effects on ligand binding and tryptophan fluorescence.

    PubMed

    May, J M; Qu, Z C; Beechem, J M

    1993-09-21

    The conformation of the human erythrocyte glucose transport protein has been shown to determine its susceptibility to enzymatic cleavage on a large cytoplasmic loop. We took the converse approach and investigated the effects of tryptic digestion on the conformational structure of this protein. Exhaustive tryptic digestion of protein-depleted erythrocyte ghosts decreased the affinity of the residual transporter for cytochalasin B by 3-fold but did not affect the total number of binding sites. Tryptic digestion also increased the affinity of the residual transporter for D-glucose and inward-binding sugar phenyl beta-D-glucopyranoside but decreased that for the outward-binding 4,6-O-ethylidene glucose. These results suggest that tryptic cleavage stabilized the remaining transporter in an inward-facing conformation, but one with decreased affinity for cytochalasin B. The steady-state fluorescence emission scan of the purified reconstituted glucose transport protein was unaffected by tryptic digestion. Addition of increasing concentrations of potassium iodide resulted in linear Stern-Volmer plots, which were also unaffected by prior tryptic digestion. The tryptophan oxidant N-bromosuccinimide was investigated to provide a more sensitive measure of tryptophan environment. This agent irreversibly inhibited 3-O-methylglucose transport in intact erythrocytes and cytochalasin B binding in protein-depleted ghosts, with a half-maximal effect observed for each activity at about 0.3-0.4 nM. Treatment of purified glucose transport protein with N-bromosuccinimide resulted in a time-dependent quench of tryptophan fluorescence, which was resolved into two components by nonlinear regression using global analysis. Tryptic digestion retarded the rate of oxidation of the more slowly reacting class of tryptophans. (ABSTRACT TRUNCATED AT 250 WORDS)

  6. Trehalose-6-phosphate-potent anti-onchocerciatic agent.

    PubMed

    Oke, J M; Watt, R A

    1998-01-01

    Onchocerciasis is a disease that engages the attention of most researchers. Presently, there is not an ideal onchocerciatic agent, hence the search must continues. Consequently alpha, alpha-trehalose-6-phosphate was synthesised and assessed for onchocerciatic activity against O. volvulus; using diethylcarbamizine citrate as the control drug. Results from this study showed that alpha, alpha-trehalose-6-phosphate is a glucose analogue with effective micro and macro-filaricidal agent, better than that of the control drug. The inhibitory action of this compound on enzyme trehalase is a postulate for the mechanism of action of trehalose-6-phosphate. The structure-activity relationship of this new compound is fully discussed. This study postulates that this compound could be used to eradicate onchocerciasis both in man and animals.

  7. Glycogen storage disease type Ia (GSDIa) but not Glycogen storage disease type Ib (GSDIb) is associated to an increased risk of metabolic syndrome: possible role of microsomal glucose 6-phosphate accumulation.

    PubMed

    Melis, Daniela; Rossi, Alessandro; Pivonello, Rosario; Salerno, Mariacarolina; Balivo, Francesca; Spadarella, Simona; Muscogiuri, Giovanna; Casa, Roberto Della; Formisano, Pietro; Andria, Generoso; Colao, Annamaria; Parenti, Giancarlo

    2015-07-29

    In GSDIa, glucose 6-phosphate (G6P) accumulates in the endoplasmic reticulum (ER); in GSDIb, G6P levels are reduced in ER. G6P availability directly modulates the activity of 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1), an ER-bound enzyme playing a key role in the development of the metabolic syndrome (MS). To evaluate the prevalence of MS and Insulin Resistance (IR) in GSDIa and GSDIb patients. This was a prospective study. All the enrolled patients were followed at the Department of Pediatrics "Federico II" University of Naples for 10 years. Clinical and biochemical parameters of MS and the presence of IR were recorded. The results were correlated with the biochemical parameters of GSDI-related metabolic control. 10 GSDIa patient (median age 12.10 ± 1.50), 7 GSDIb patients (median age 14.90 ± 2.20 were enrolled in the study. They were compared to 20 and 14 age and sex matched controls, respectively. 10 GSDIa patients (median age 24.60 ± 1.50) and 6 GSDIb patients (median age 25.10 ± 2.00) completed the 10-year-follow-up. At the end of the study the patients' data were compared to 10 and 6 age and sex matched controls, respectively. At study entry, 20 % GSDIa patients had MS and 80 % showed 2 criteria for MS. GSDIa patients showed higher HOMA-IR than controls and GSDIb patients (p < 0.001, p < 0.05), respectively. Baseline ISI was lower in GSDIa than controls (p < 0.001). QUICKI was significantly lower in GSDIa than in controls (p < 0.001). At the end of the study 70 % of GSDIa patients had MS and 30 % showed 2 criteria for MS. HOMA-IR was higher in GSDIa than controls (p < 0.01). Baseline ISI was higher in GSDIb than controls (p < 0.005) and GSD1a (p < 0.05). QUICKI was lower in GSD1a patients than in controls (p < 0.03). VAI was higher in GSDIa patients than controls (p < 0.001) and GSDIb patients (p = 0.002). Our data showed high prevalence of IR and MS in GSDIa patients. We speculate a

  8. Glucose-6-phosphate dehydrogenase-dependent hydrogen peroxide production is involved in the regulation of plasma membrane H+-ATPase and Na+/H+ antiporter protein in salt-stressed callus from Carex moorcroftii.

    PubMed

    Li, Jisheng; Chen, Guichen; Wang, Xiaomin; Zhang, Yanli; Jia, Honglei; Bi, Yurong

    2011-03-01

    Glucose-6-phosphate dehydrogenase (G6PDH) is important for the activation of plant resistance to environmental stresses, and ion homeostasis is the physiological foundation for living cells. In this study, we investigated G6PDH roles in modulating ion homeostasis under salt stress in Carex moorcroftii callus. G6PDH activity increased to its maximum in 100 mM NaCl treatment and decreased with further increased NaCl concentrations. K+/Na+ ratio in 100 mM NaCl treatment did not exhibit significant difference compared with the control; however, in 300 mM NaCl treatment, it decreased. Low-concentration NaCl (100 mM) stimulated plasma membrane (PM) H+-ATPase and NADPH oxidase activities as well as Na+/H+ antiporter protein expression, whereas high-concentration NaCl (300 mM) decreased their activity and expression. When G6PDH activity and expression were reduced by glycerol treatments, PM H+-ATPase and NADPH oxidase activities, Na+/H+ antiporter protein level and K+/Na+ ratio dramatically decreased. Simultaneously, NaCl-induced hydrogen peroxide (H₂O₂) accumulation was abolished. Exogenous application of H₂O₂ increased G6PDH, PM H+-ATPase and NADPH oxidase activities, Na+/H+ antiporter protein expression and K+/Na+ ratio in the control and glycerol treatments. Diphenylene iodonium (DPI), the NADPH oxidase inhibitor, which counteracted NaCl-induced H₂O₂ accumulation, decreased G6PDH, PM H+-ATPase and NADPH oxidase activities, Na+/H+ antiporter protein level and K+/Na+ ratio. Western blot result showed that G6PDH expression was stimulated by NaCl and H₂O₂, and blocked by DPI. Taken together, G6PDH is involved in H₂O₂ accumulation under salt stress. H₂O₂, as a signal, upregulated PM H+-ATPase activity and Na+/H+ antiporter protein level, which subsequently resulted in the enhanced K+/Na+ ratio. G6PDH played a central role in the process.

  9. Effects of antioxidant supplementation on mRNA expression of glucose-6-phosphate dehydrogenase, β-actin and 18S rRNA in the anterior capsule of the lens in cataract patients.

    PubMed

    Hayashi, Rijo; Hayashi, Shimmin; Arai, Kiyomi; Chikuda, Makoto; Obara, Yositaka

    2012-03-01

    This was a preliminary study of the effects of antioxidant supplementation on the peroxidation status of the lens by investigating mRNA expression of anti-oxidative enzymes in the lens. The mRNA expression levels of glucose-6-phosphate dehydrogenase (G6PDH), β-actin (β-ACT) and 18S rRNA (18S) were measured in this study because they are common reference genes for measuring mRNA levels by means of a real-time reverse transcription polymerase chain reaction (RT-PCR) in various tissues. Thirteen patients with binocular cataracts of the same grade were included in the study after giving informed consent. A piece of the anterior capsule, along with a sample of lenticular epithelial cells (LECs), was collected as a pre-intake sample during cataract surgery. Ocuvite + Lutein(®), an antioxidant supplement, was administered orally beginning the day after surgery. Six weeks later, a piece of the anterior capsule along with a sample of LECs, was collected as a post-intake sample during cataract surgery of the opposite eye. RNA was purified from the homogenized samples, and cDNA was reverse transcribed to measure mRNA levels. The expression levels of G6PDH, 18S and β-ACT were measured using RT-PCR. The expression levels of G6PDH and 18S were significantly higher in the post-intake samples than they were in the pre-intake samples. Significant positive correlations between the expression levels of G6PDH and 18S were observed in both the pre- and post-intake samples. Following gender-specific analyses, the expression levels of G6PDH and 18S in the post-intake samples were found to be significantly higher among the female patients. A significant positive correlation between the expression levels of G6PDH and 18S was observed in the post-intake samples from the male patients. There were no significant changes in the gene expression levels of β-ACT after supplementation among male or female patients. β-ACT has been verified for use as a reference gene for measuring the

  10. Glucose-6-phosphate dehydrogenase from brewers' yeast. The effects of pH and temperature on the steady-state kinetic parameters of the two-chain protein species.

    PubMed

    Kuby, S A; Roy, R N

    1976-05-04

    A systematic study has been made of the pH- and temperature-dependency of the steady-state kinetic parameters of the stabilized two-subunit enzyme species of glucose-6-phosphate dehydrogenase, in the absence of superimposed association-dissociation reactions. The Vmax(app) data obtained in several buffers between pH 5 and 10 and at 18-32 degrees C lead to the postulate that at least two sets of protonic equilibria may govern the catalysis (one near pH 5.7 AT 25 DEGREES C and another near pH 9.2); furthermore, two pathways for product formation (i.e., two Vmax's) appear to be required to explain the biphasic nature of the log Vmax(app) vs. pH curves, with Vmax(basic) greater than Vmax(acidic + neutral). Of the several buffers explored, either a uniform degree of interaction or a minimal degree of buffer species interaction could be assessed from the enthalpy changes associated with the derived values for ionization constants attributed to the protonic equilibria in the enzyme-substrates ternary complexes for the case of Tris-acetate-EDTA buffers, at constant ionic strength. With the selection of this buffer at 0.1 (T/2) and at 25 and 32 degrees C, a self-consistent kinetic mechanism has emerged which allows for the random binding of the two fully ionized substrates to the enzyme via two major pathways, and product formation by both E-A--B- and HE-A--B-. As before (Kuby et al. Arch. Biochem, Biophys. 165, 153-178, 1974), a quasi-equilibrium is presumed, with rate-limiting steps (k + 5 and k + 5') at the interconversion of the ternary complexes. Values for the two sets of protonic equilibria defined by this mechanism (viz., pKk, pKH2 for the first ionizations, and pKk', pKH' for the second) could then be estimated. From their numerical values (e.g., at 25 degrees C: pKK = 5.7 PKH2 = 5.2; and pKK' = 9.1, PKH' = 8.2) and from the values for delta H degrees ioniz (e.g., delta H degrees pKK APPROXIMATELY 5.1 KCAL/MOL; DELTA H degrees pKK' APPROXIMATELY 11 KCAL/MOL), A

  11. [The regulation of glucose-6-phosphate dehydrogenase and glycogen synthase activities by insulin superfamily peptides in myometrium of pregnant women and its impairments under different types of diabetes mellitus].

    PubMed

    Kuznetsova, L A; Chistiakova, O V

    2009-01-01

    The regulatory effects of insulin, insulin-like growth factor 1 (IGF-1), and relaxin on glucose-6-phosphate dehydrogenase (G6PDH) and glycogen synthase (GS) activities have been studied in myometrium of pregnant women of control group and with diabetes mellitus of different etiology. In patients with type 1 diabetes G6PDH activity did not differ from the control group, but the enzyme activity was sharply decreased in pregnant women with type 2 diabetes and gestational diabetes. In the control group maximal stimulation of G6PDH activity was observed at 10(-9) M of peptides and their stimulating effect decreased in the following order: insulin > relaxin > IGF-1. In pregnant women with types 1 diabetes insulin effect on the enzyme activity was lower than in the control, and the effects of IGF-1 and relaxin were absent. In the group of pregnant women with type 2 diabetes and gestational diabetes the effects of insulin and IGF-1 were decreased, but the effect of relaxin was somewhat higher thus giving the following order in their efficiency relaxin > IGF-1 = insulin. At 10(-9) M peptides exhibited similar stimulating effects on the active form of GS-I, but had no influence on the total enzyme activity in the control group of pregnant women. In patients with type 1 diabetes GS activity remained unchanged (versus control), and peptides did not stimulate the enzyme activity. In patients with type 2 diabetes a significant decrease in GS activity was accompanied by the decrease in the effect of peptides, giving the following order of their efficiency: insulin = IGF-1 > relaxin. In myometrium of pregnant women with gestational (treated and untreated) diabetes GS activity decreased, the effect of insulin was weaker, whereas the effects of relaxin and IGF-1 increased thus giving the following order of their efficiency: relaxin > IGF-1 > insulin. Insulin therapy of type 1 diabetes incompletely restored sensitivity of the enzymes to the peptide actions. At the same time, in women

  12. A quantitative cytochemical study of glucose-6-phosphate dehydrogenase and delta 5-3 beta-hydroxysteroid dehydrogenase activity in the membrana granulosa of the ovulable type of follicle of the rat.

    PubMed

    Zoller, L C; Weisz, J

    1979-08-01

    During the last four days of follicular development prior to ovulation, the activities of delta 5-3 beta-hydroxysteroid dehydrogenase (3 beta OHD) and glucose-6-phosphate dehydrogenase (G-6-PD) were quantified in cryostat sections of the rat ovary. The product of the enzyme reactions were measured using a scanning and integrating microdensitometer. The enzyme activity was measured in the peripheral region, the antral region and the cumulus of the membrana granulosa (MG) of these follicles on the morning of each of the four days of the estrous cycle. G-6-PD activity was measured in the presence and absence of an intermediate hydrogen acceptor, phenazine methosulphate, to provide a measure of the quantity of Type I and Type II Hydrogen (H) generated: Type I H is considered to be related to hydroxylating reactions such as those of steroids and Type II H to other general biosynthetic activities of cells. In all three regions of the MG of follicles of the ovulable type, 3 beta OHD activity was lowest in estrus and diestrus-1, increased on diestrus-2 and peaked in proestrus. In estrus and diestrus-1, the level of 3 beta OHD activity in the three regions was comparable. However, by diestrus-2, and even more conspicuously in proestrus, enzyme activity was significantly greater in the peripheral region than in the antral region or in the cumulus. During the same period, the level of enzyme activity remained comparable in the last two regions. Throughout the estrous cycle, both Type I and Type II H generation from G-6-PD was greatest in the peripheral region, less in the antral region and least in the cumulus. In the eripheral region, Type I H generation increased progressively after diestrus-1, to reach a maximum in prestrus. In the antral region, Type I H generation increased between diestrus-1 and diestrus-2 and then remained unchanged through proestrus. In the cumulus, Type I H generation remained at levels seen in estrus throughout the remainder of the cycle. Generation

  13. Risks of Hemolysis in Glucose-6-Phosphate Dehydrogenase Deficient Infants Exposed to Chlorproguanil-Dapsone, Mefloquine and Sulfadoxine-Pyrimethamine as Part of Intermittent Presumptive Treatment of Malaria in Infants.

    PubMed

    Poirot, Eugenie; Vittinghoff, Eric; Ishengoma, Deus; Alifrangis, Michael; Carneiro, Ilona; Hashim, Ramadhan; Baraka, Vito; Mosha, Jacklin; Gesase, Samwel; Chandramohan, Daniel; Gosling, Roland

    2015-01-01

    Chlorproguanil-dapsone (CD) has been linked to hemolysis in symptomatic glucose-6-phosphate dehydrogenase deficient (G6PDd) children. Few studies have explored the effects of G6PD status on hemolysis in children treated with Intermittent Preventive Treatment in infants (IPTi) antimalarial regimens. We sought to examine the joint effects of G6PD status and IPTi antimalarial treatment on incidence of hemolysis in asymptomatic children treated with CD, sulfadoxine-pyrimethamine (SP), and mefloquine (MQ). A secondary analysis of data from a double-blind, placebo-controlled trial of IPTi was conducted. Hemoglobin (Hb) measurements were made at IPTi doses, regular follow-up and emergency visits. G6PD genotype was determined at 9 months looking for SNPs for the A- genotype at coding position 202. Multivariable linear and logistic regression models were used to examine hemolysis among children with valid G6PD genotyping results. Hemolysis was defined as the absolute change in Hb or as any post-dose Hb <8 g/dL. These outcomes were assessed using either a single follow-up Hb on day 7 after an IPTi dose or Hb obtained 1 to 14 or 28 days after each IPTi dose. Relative to placebo, CD reduced Hb by approximately 0.5 g/dL at day 7 and within 14 days of an IPTi dose, and by 0.2 g/dL within 28 days. Adjusted declines in the CD group were larger than in the MQ and SP groups. At day 7, homo-/hemizygous genotype was associated with higher odds of Hb <8 g/dL (adjusted odds ratio = 6.7, 95% CI 1.7 to 27.0) and greater absolute reductions in Hb (-0.6 g/dL, 95% CI -1.1 to 0.003). There was no evidence to suggest increased reductions in Hb among homo-/hemizygous children treated with CD compared to placebo, SP or MQ. While treatment with CD demonstrated greater reductions in Hb at 7 and 14 days after an IPTi dose compared to both SP and MQ, there was no evidence that G6PD deficiency exacerbated the adverse effects of CD, despite evidence for higher hemolysis risk among G6PDd infants.

  14. Re-examination of the roles of PEP and Mg2+ in the reaction catalysed by the phosphorylated and non-phosphorylated forms of phosphoenolpyruvate carboxylase from leaves of Zea mays. Effects of the activators glucose 6-phosphate and glycine.

    PubMed Central

    Tovar-Méndez, A; Rodríguez-Sotres, R; López-Valentín, D M; Muñoz-Clares, R A

    1998-01-01

    To study the effects of phosphoenolpyruvate (PEP) and Mg2+ on the activity of the non-phosphorylated and phosphorylated forms of phosphoenolpyruvate carboxylase (PEPC) from Zea mays leaves, steady-state measurements have been carried out with the free forms of PEP (fPEP) and Mg2+ (fMg2+), both in a near-physiological concentration range. At pH 7.3, in the absence of activators, the initial velocity data obtained with both forms of the enzyme are consistent with the exclusive binding of MgPEP to the active site and of fPEP to an activating allosteric site. At pH 8.3, and in the presence of saturating concentrations of glucose 6-phosphate (Glc6P) or Gly, the free species also combined with the active site in the free enzyme, but with dissociation constants at least 35-fold that estimated for MgPEP. The latter dissociation constant was lowered to the same extent by saturating Glc6P and Gly, to approx. one-tenth and one-sixteenth in the non-phosphorylated and phosphorylated enzymes respectively. When Glc6P is present, fPEP binds to the active site in the free enzyme better than fMg2+, whereas the metal ion binds better in the presence of Gly. Saturation of the enzyme with Glc6P abolished the activation by fPEP, consistent with a common binding site, whereas saturation with Gly increased the affinity of the allosteric site for fPEP. Under all the conditions tested, our results suggest that fPEP is not able to combine with the allosteric site in the free enzyme, i.e. it cannot combine until after MgPEP, fPEP or fMg2+ are bound at the active site. The physiological role of Mg2+ in the regulation of the enzyme is only that of a substrate, mainly as part of the MgPEP complex. The kinetic properties of maize leaf PEPC reported here are consistent with the enzyme being well below saturation under the physiological concentrations of fMg2+ and PEP, particularly during the dark period; it is therefore suggested that the basal PEPC activity in vivo is very low, but highly

  15. Metabolic alterations in the human erythrocyte produced by increases in glucose concentration

    PubMed Central

    Travis, Susan F.; Morrison, Anthony D.; Clements, Rex S.; Winegrad, Albert I.; Oski, Frank A.

    1971-01-01

    Human erythrocytes incubated in medium containing 50 mM glucose have increased intracellular sorbitol and fructose concentrations as compared with samples incubated with 5 mM glucose. Increased medium glucose concentration did not significantly alter total glucose consumption or lactate production. However, the intracellular lactate:pyruvate ratio rose, the concentrations of fructose diphosphate, and triose phosphates increased, and the 2,3-diphosphoglycerate concentration fell. [14C]O2 production from glucose-1-14C also increased with increased medium glucose concentration. These changes are believed to reflect changes in the redox states of the diphosphopyridine nucleotide/reduced form of diphosphopyridine nucleotide (NAD/NADH) and nicotinamide—adenine dinucleotide phosphate/reduced form of nicotinamide—adenine dinucleotide phosphate (NADP/NADPH) couples resulting from increased activity of the polyol pathway. Addition of pyruvate to the incubation media prevented these changes. These studies illustrate that an increase in the red cell's normal substrate, glucose, can produce changes in red cell metabolism. PMID:4398937

  16. Cholate-solubilized erythrocyte glucose transporters exist as a mixture of homodimers and homotetramers.

    PubMed

    Hebert, D N; Carruthers, A

    1991-05-14

    The molecular size of purified, human erythrocyte glucose transport protein (GLUT1) solubilized in cholic acid was determined by size-exclusion chromatography (SEC) and sucrose gradient ultracentrifugation. GLUT1 purified in the presence of dithiothreitol (GLUT1 + DTT) is resolved as a complex of average Stokes' radius 5.74 nm by SEC. This complex displays D-glucose-inhibitable cytochalasin B binding and, upon reconstitution into proteoliposomes, catalyzes cytochalasin B inhibitable D-glucose transport. GLUT1 purified in the absence of dithiothreitol (GLUT1-DTT) is resolved by SEC as at least two particles of average Stokes' radii 5.74 (minor component) and 7.48 nm (major component). Solubilization of GLUT1-DTT in the presence of dithiothreitol reduces the amount of 7.48-nm complex and increases the amount of 5.74-nm complex resolved by SEC. GLUT1-DTT displays D-glucose-inhibitable cytochalasin B binding and, upon reconstitution into proteoliposomes, catalyzes cytochalasin B inhibitable D-glucose transport. Sucrose gradient ultracentrifugation of GLUT1 + DTT in cholate resolves GLUT1 into two components of 4.8 and 7.6 S. The 4.8S complex is the major component of GLUT1 + DTT. The reverse profile is observed upon sucrose gradient ultracentrifugation of GLUT1-DTT. SEC of human erythrocyte membrane proteins resolves GLUT1 as a major broad peak of average Stokes' radius 7.48 nm and a minor component of 5.74 nm. Both components are characterized by D-glucose-inhibitable cytochalasin B binding. Purified GLUT1 is associated with approximately 26 tightly bound lipid molecules per monomer of transport protein. These data suggest that purified GLUT1 exists as a mixture of homodimers and homotetramers in cholate-lipid micelles and that the presence of reductant during solubilization favors dimer formation.

  17. Elongation index of erythrocytes, study of activity of chosen erythrocyte enzymes, and the levels of glutathione, malonyldialdehyde in polycythemia vera (PV).

    PubMed

    Dąbrowski, Z; Dybowicz, A J; Marchewka, A; Teległów, A; Skotnicki, A; Zduńczyk, A; Aleksander, P; Filar-Mierzwa, K

    2011-01-01

    The principal aim of the study was to investigate rheological properties of erythrocytes obtained from patients admitted to the clinic, and diagnosed with polycythemia vera. The polycythemia vera diagnosis was based on the WHO criteria for polycythemia vera. Using a laser rheometer SSD Rheometer-Rheodyn, the elongation index of erythrocytes was determined, indicating an increased rigidity of the erythrocytes in this disease compared with the erythrocytes in healthy people. In order to explain (albeit partially) the reason for reduced elasticity, the erythrocytes of patients with polycythemia were studied for the activity of enzymes - glucose-6-phosphate dehydrogenase and acetylcholinesterase membrane enzyme, as well as the levels of glutathione and malonyldialdehyde. The elevated activities of these enzymes, the glutathione level, and elevated ‰ of reticulocytes, indicated an increased pool of juvenile erythrocyte forms; furthermore, the elevated value of malonyldialdehyde may suggest a lipid peroxidative damage in certain pool of the erythrocyte membrane in blood circulation.

  18. Hypoglycaemic activity of Coccinia indica and Momordica charantia in diabetic rats: depression of the hepatic gluconeogenic enzymes glucose-6-phosphatase and fructose-1,6-bisphosphatase and elevation of both liver and red-cell shunt enzyme glucose-6-phosphate dehydrogenase.

    PubMed Central

    Shibib, B A; Khan, L A; Rahman, R

    1993-01-01

    Coccinia indica leaves were extracted with 60% ethanol, solvents were evaporated and the residue was suspended in water. This suspension was administered orally at a dose of 200 mg/kg body wt. after 18 h of fasting to normal fed and streptozotocin-induced male diabetic rats (180-250 g). After 90 min the rats were killed, and blood-glucose, hepatic glucose-6-phosphatase, fructose-1,6-bisphosphatase and glucose-6-phosphate dehydrogenase (G6PDH) and red-cell G6PDH were assayed. Blood sugar was depressed by 23% (P < 0.01) and 27% (P < 0.001) in the normal fed and streptozotocin-diabetic rats respectively compared with controls which were given distilled water. Hepatic glucose-6-phosphatase and fructose-1,6-bisphosphatase activities were depressed by 32% (P < 0.001) 30% (P < 0.05) respectively in the streptozotocin-diabetic rats, compared with 19% (P < 0.02) and 20% (P < 0.01) depression in the normal fed controls, whereas both the red-cell and hepatic G6PDH activities were found to be elevated by feeding the extract in the streptozotocin-diabetic and in the normal fed controls. Similar results were obtained with the 95%-ethanolic extract of Momordica charantia. Taken together, these results indicate that Coccinia indica and Momordica charantia extracts lowered blood glucose by depressing its synthesis, on the one hand through depression of the key gluconeogenic enzymes glucose-6-phosphatase and fructose-1,6-bisphosphatase and on the other by enhancing glucose oxidation by the shunt pathway through activation of its principal enzyme G6PDH. PMID:8389127

  19. Human Erythrocyte Glucose Transporter: Normal Asymmetric Orientation and Function in Liposomes

    NASA Astrophysics Data System (ADS)

    Chen, Chia-Chen; Kurokawa, Tomonori; Shaw, Shyh-Yu; Tillotson, Loyal G.; Kalled, Susan; Isselbacher, Kurt J.

    1986-04-01

    The transport function and orientation of the reconstituted human erythrocyte glucose transporter was studied with liposomes made with bovine brain lipid or Escherichia coli lipid. Reconstitution was achieved by a simple octyl glucoside dilution method. The reconstituted transporters with either lipid showed identical counterflow transport activity, the same response to various inhibitors, and characteristic cytochalasin B (CB) labeling. Functional location and purification of the glucose transporter was performed by using gel-permeation high-performance liquid chromatography with octyl glucoside-containing buffer. The reconstituted transport activity was associated only with band 4.5 protein (preactin) and not with band 3 protein. Both CB binding and transport function of the reconstituted transporters were resistant to trypsin but susceptible to chymotrypsin digestion. However, both trypsin and chymotrypsin treatment of unsealed ghosts completely eliminated the CB labeling and transport function of the glucose transporter. In our reconstitution system the glucose transporters maintained a normal asymmetrical (rightside-out) orientation and good transport function. A specific monoclonal antibody against the glucose transporter inhibited CB labeling of the transporters on unsealed ghosts. This was not found with the reconstituted system; however, after freeze-thawing there was a significant inhibition of CB binding by the antibody. These findings suggest that the CB-binding site of the reconstituted transporter is on the inner side of the proteoliposomes.

  20. Interaction of steroids with the transport system of glucose in human erythrocytes.

    PubMed

    Lacko, L; Wittke, B; Geck, P

    1975-12-01

    Steroids inhibit the exchange transport of glucose in human erythrocytes. The extent of inhibition is roughly correlated to the affinity of the steroids to the membrane lipids. All C-21-steroids tested show a competitive inhibition while the C-19-steriods show different types of inhibition. 5Beta-androstane-3,17-dione acts as a competitive inhibitor. The inhibition by testosterone is of mixed type, while with androst-4-ene-3,17-dione and 5alpha-androstane-3,17-dione a non-competitive inhibition is observed. In this case two inhibitor molecules can be bound per transport molecule. The "non-competitive" inhibitors compete also to some extent with the glucose binding. This effect, however, is at high inhibitor concentrations masked by the more powerful non-competitive inhibition. Competitive and non-competitive inhibitors compete with each other. The structural requirements for the different types of inhibition are discussed.

  1. Discovery of a Plasmodium falciparum glucose-6-phosphate dehydrogenase 6- phosphogluconolactonase inhibitor (R,Z)-N-((1-ethylpyrrolidin-2-yl)methyl)-2-(2-fluorobenzylidene)-3-oxo-3,4-dihydro-2H-benzo[b][1,4]thiazine-6-carboxamide (ML276) that reduces parasite growth in vitro

    PubMed Central

    Preuss, Janina; Maloney, Patrick; Peddibhotla, Satyamaheshwar; Hedrick, Michael P.; Hershberger, Paul; Gosalia, Palak; Milewski, Monika; Li, Yujie Linda; Sugarman, Eliot; Hood, Becky; Suyama, Eigo; Nguyen, Kevin; Vasile, Stefan; Sergienko, Eduard; Mangravita-Novo, Arianna; Vicchiarelli, Michael; McAnally, Danielle; Smith, Layton H.; Roth, Gregory P.; Diwan, Jena; Chung, Thomas D.Y.; Jortzik, Esther; Rahlfs, Stefan; Becker, Katja; Pinkerton, Anthony B.; Bode, Lars

    2012-01-01

    A high throughput screen of the NIH’s MLSMR collection of ~340,000 compounds was undertaken to identify compounds that inhibit Plasmodium falciparum glucose-6-phosphate dehydrogenase (PfG6PD). PfG6PD is essential for proliferating and propagating P. falciparum and differs structurally and mechanistically from the human ortholog. The reaction catalyzed by glucose-6-phosphate dehydrogenase (G6PD) is the first, rate-limiting step in the pentose phosphate pathway (PPP), a key metabolic pathway sustaining anabolic needs in reductive equivalents and synthetic materials in fastgrowing cells. In P. falciparum the bifunctional enzyme glucose-6-phosphate dehydrogenase-6- phosphogluconolactonase (PfGluPho) catalyzes the first two steps of the PPP. Because P. falciparum and infected host red blood cells rely on accelerated glucose flux, they depend on the G6PD activity of PfGluPho. The lead compound identified from this effort, (R,Z)-N-((1-ethylpyrrolidin-2-yl)methyl)-2- (2-fluorobenzylidene)-3-oxo-3,4-dihydro-2H-benzo[b][1,4]thiazine-6-carboxamide, 11, (ML276), is a submicromolar inhibitor of PfG6PD (IC50 = 889 nM). It is completely selective for the enzyme’s human isoform, displays micromolar potency (IC50 = 2.6 μM) against P. falciparum in culture, and has good drug-like properties, including high solubility and moderate microsomal stability. Studies testing the potential advantage of inhibiting PfG6PD in vivo are in progress. PMID:22813531

  2. /sup 3/H)forskolin. Direct photoaffinity labeling of the erythrocyte D-glucose transporter

    SciTech Connect

    Shanahan, M.F.; Morris, D.P.; Edwards, B.M.

    1987-05-05

    Irradiation of erythrocyte ghosts in the presence of (/sup 3/H)forskolin resulted in a concentration-dependent, covalent incorporation of radiolabel into several of the major membrane protein bands. Most of the incorporation occurred in four regions of the gel. Peak 1 (216 kDa) was a sharp peak near the top of the gel in the region corresponding to spectrin. Peak 2 appeared to be associated with band 3 (89 kDa), while a third peak occurred around the position of band 4.2 (76 kDa). The fourth region of labeling was a broad area between 43-75 kDa which corresponds to the region of the glucose transporter. Forskolin labeling of this region was inhibited by cytochalasin B and D-glucose, but not L-glucose. Extraction of extrinsic membrane proteins resulted in a loss of radiolabeled protein from the 216- and 76-kDa regions. Treatment of membranes labeled with either cytochalasin B or forskolin with endo-beta-galactosidase resulted in identical shifts of the 43 to 75-kDa peaks to 42 kDa. Similarly, trypsinization of membranes photolabeled with either cytochalasin B or forskolin resulted in the generation of a 17-kDa radiolabeled fragment in both cases. Photoincorporation of (/sup 3/H)cytochalasin B into the glucose transporter was blocked in a concentration-dependent manner by unlabeled forskolin.

  3. FRUCTOSE-6-PHOSPHATE REDUCTASE FROM SALMONELLA GALLINARUM

    PubMed Central

    Zancan, Glaci T.; Bacila, Metry

    1964-01-01

    Zancan, Glaci T. (Universidade do Paraná, Curitiba, Paraná, Brazil), and Metry Bacila. Fructose-6-phosphate reductase from Salmonella gallinarum. J. Bacteriol. 87:614–618. 1964.—A fructose-6-phosphate reductase present in cell-free extracts of Salmonella gallinarum was purified approximately 42 times. The optimal pH for this enzyme is 8.0. The enzyme is specific for fructose-6-phosphate and reduced nicotinamide adenine dinucleotide (NADH). The dissociation constants are 1.78 × 10−4m for fructose-6-phosphate and 8.3 × 10−5m for NADH. The Q10, reaction order, and equilibrium constant were determined. The enzyme is sensitive to p-chloromercuribenzoic acid, but not to o-iodosobenzoic acid nor to N-ethylmaleimide. PMID:14127579

  4. Overproduction of Trehalose: Heterologous Expression of Escherichia coli Trehalose-6-Phosphate Synthase and Trehalose-6-Phosphate Phosphatase in Corynebacterium glutamicum

    PubMed Central

    Padilla, Leandro; Krämer, Reinhard; Stephanopoulos, Gregory; Agosin, Eduardo

    2004-01-01

    Trehalose is a disaccharide with potential applications in the biotechnology and food industries. We propose a method for industrial production of trehalose, based on improved strains of Corynebacterium glutamicum. This paper describes the heterologous expression of Escherichia coli trehalose-synthesizing enzymes trehalose-6-phosphate synthase (OtsA) and trehalose-6-phosphate phosphatase (OtsB) in C. glutamicum, as well as its impact on the trehalose biosynthetic rate and metabolic-flux distributions, during growth in a defined culture medium. The new recombinant strain showed a five- to sixfold increase in the activity of OtsAB pathway enzymes, compared to a control strain, as well as an almost fourfold increase in the trehalose excretion rate during the exponential growth phase and a twofold increase in the final titer of trehalose. The heterologous expression described resulted in a reduced specific glucose uptake rate and Krebs cycle flux, as well as reduced pentose pathway flux, a consequence of downregulated glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase. The results proved the suitability of using the heterologous expression of Ots proteins in C. glutamicum to increase the trehalose biosynthetic rate and yield and suggest critical points for further improvement of trehalose overproduction in C. glutamicum. PMID:14711665

  5. Transport and subcellular distribution characteristics of human erythrocyte glucose transporter fused in adipocytes

    SciTech Connect

    Jo, Inho.

    1990-01-01

    Purified human erythrocyte glucose transporters (HEGT) were incorporated into the rat epididymal adipocytes by polyethylene glycol (PEG)-induced fusion. The incorporation of HEGT was found to be dependent on both the molecular weight and the concentration of PEG. Optimal incorporation of HEGT occurred when 10% PEG 8000 was used. This incorporation was found to be proportional to the increasing amounts of HEGT used. Morphology tests showed very little surface adsorption of HEGT on adipocytes after fusion. Transport activity of fused HEGT was studied by measuring equilibrium exchange of 3-O-methylglucose. In adipocytes employed this fusion protocols, the transport rate increased significantly compared with cells treated under non-fusion conditions. This fold increase was directly proportional to the amount of HEGT recovered in the plasma membrane (PM). Furthermore, calculated turnover number of HEGT in fused adipocytes was as high as that of the native adipocyte glucose transporter (AGT). Subcellular distribution of HEGT in fused adipocytes was assessed using ({sup 3}H)cytochalasin B-labeled HEGT vesicles. HEGT was distributed in each subcellular organelle at specific ratios. This relative distribution was almost constant regardless of the amount of HEGT used. The distributions of lipid-labeled HEGT, fluid-phase endocytosed HEGT and free HEGT mixed to adipocyte homogenate were shown to be completely different from that of protein-labeled HEGT fusion.

  6. Piracetam and TRH analogues antagonise inhibition by barbiturates, diazepam, melatonin and galanin of human erythrocyte D-glucose transport.

    PubMed

    Naftalin, Richard J; Cunningham, Philip; Afzal-Ahmed, Iram

    2004-06-01

    1 Nootropic drugs increase glucose uptake into anaesthetised brain and into Alzheimer's diseased brain. Thyrotropin-releasing hormone, TRH, which has a chemical structure similar to nootropics increases cerebellar uptake of glucose in murine rolling ataxia. This paper shows that nootropic drugs like piracetam (2-oxo 1 pyrrolidine acetamide) and levetiracetam and neuropeptides like TRH antagonise the inhibition of glucose transport by barbiturates, diazepam, melatonin and endogenous neuropeptide galanin in human erythrocytes in vitro. 2 The potencies of nootropic drugs in opposing scopolamine-induced memory loss correlate with their potencies in antagonising pentobarbital inhibition of erythrocyte glucose transport in vitro (P<0.01). Less potent nootropics, D-levetiracetam and D-pyroglutamate, have higher antagonist Ki's against pentobarbital inhibition of glucose transport than more potent L-stereoisomers (P<0.001). 3 Piracetam and TRH have no direct effects on net glucose transport, but competitively antagonise hypnotic drug inhibition of glucose transport. Other nootropics, like aniracetam and levetiracetam, while antagonising pentobarbital action, also inhibit glucose transport. Analeptics like bemigride and methamphetamine are more potent inhibitors of glucose transport than antagonists of hypnotic action on glucose transport. 4 There are similarities between amino-acid sequences in human glucose transport protein isoform 1 (GLUT1) and the benzodiazepine-binding domains of GABAA (gamma amino butyric acid) receptor subunits. Mapped on a 3D template of GLUT1, these homologies suggest that the site of diazepam and piracetam interaction is a pocket outside the central hydrophilic pore region. 5 Nootropic pyrrolidone antagonism of hypnotic drug inhibition of glucose transport in vitro may be an analogue of TRH antagonism of galanin-induced narcosis.

  7. Piracetam and TRH analogues antagonise inhibition by barbiturates, diazepam, melatonin and galanin of human erythrocyte D-glucose transport

    PubMed Central

    Naftalin, Richard J; Cunningham, Philip; Afzal-Ahmed, Iram

    2004-01-01

    Nootropic drugs increase glucose uptake into anaesthetised brain and into Alzheimer's diseased brain. Thyrotropin-releasing hormone, TRH, which has a chemical structure similar to nootropics increases cerebellar uptake of glucose in murine rolling ataxia. This paper shows that nootropic drugs like piracetam (2-oxo 1 pyrrolidine acetamide) and levetiracetam and neuropeptides like TRH antagonise the inhibition of glucose transport by barbiturates, diazepam, melatonin and endogenous neuropeptide galanin in human erythrocytes in vitro. The potencies of nootropic drugs in opposing scopolamine-induced memory loss correlate with their potencies in antagonising pentobarbital inhibition of erythrocyte glucose transport in vitro (P<0.01). Less potent nootropics, D-levetiracetam and D-pyroglutamate, have higher antagonist Ki's against pentobarbital inhibition of glucose transport than more potent L-stereoisomers (P<0.001). Piracetam and TRH have no direct effects on net glucose transport, but competitively antagonise hypnotic drug inhibition of glucose transport. Other nootropics, like aniracetam and levetiracetam, while antagonising pentobarbital action, also inhibit glucose transport. Analeptics like bemigride and methamphetamine are more potent inhibitors of glucose transport than antagonists of hypnotic action on glucose transport. There are similarities between amino-acid sequences in human glucose transport protein isoform 1 (GLUT1) and the benzodiazepine-binding domains of GABAA (gamma amino butyric acid) receptor subunits. Mapped on a 3D template of GLUT1, these homologies suggest that the site of diazepam and piracetam interaction is a pocket outside the central hydrophilic pore region. Nootropic pyrrolidone antagonism of hypnotic drug inhibition of glucose transport in vitro may be an analogue of TRH antagonism of galanin-induced narcosis. PMID:15148255

  8. Trehalose biosynthesis in Thermus thermophilus RQ-1: biochemical properties of the trehalose-6-phosphate synthase and trehalose-6-phosphate phosphatase.

    PubMed

    Silva, Zélia; Alarico, Susana; da Costa, Milton S

    2005-02-01

    The genes for trehalose synthesis in Thermus thermophilus RQ-1, namely otsA [trehalose-phosphate synthase (TPS)], otsB [trehalose-phosphate phosphatase (TPP)], and treS [trehalose synthase (maltose converting) (TreS)] genes are structurally linked. The TPS/TPP pathway plays a role in osmoadaptation, since mutants unable to synthesize trehalose via this pathway were less osmotolerant, in trehalose-deprived medium, than the wild-type strain. The otsA and otsB genes have now been individually cloned and overexpressed in Escherichia coli and the corresponding recombinant enzymes purified. The apparent molecular masses of TPS and TPP were 52 and 26 kDa, respectively. The recombinant TPS utilized UDP-glucose, TDP-glucose, ADP-glucose, or GDP-glucose, in this order as glucosyl donors, and glucose-6-phosphate as the glucosyl acceptor to produce trehalose-6-phosphate (T6P). The recombinant TPP catalyzed the dephosphorylation of T6P to trehalose. This enzyme also dephosphorylated G6P, and this activity was enhanced by NDP-glucose. TPS had an optimal activity at about 98 degrees C and pH near 6.0; TPP had a maximal activity near 70 degrees C and at pH 7.0. The enzymes were extremely thermostable: at 100 degrees C, TPS had a half-life of 31 min, and TPP had a half-life of 40 min. The enzymes did not require the presence of divalent cations for activity; however, the presence of Co2+ and Mg2+ stimulates both TPS and TPP. This is the first report of the characterization of TPS and TPP from a thermophilic organism.

  9. Therapeutic potential of manipulating suicidal erythrocyte death.

    PubMed

    Lang, Florian; Jilani, Kashif; Lang, Elisabeth

    2015-01-01

    Eryptosis, the suicidal erythrocyte death, is characterized by erythrocyte shrinkage and phosphatidylserine translocation to the erythrocyte surface. Eryptosis is triggered by cell stress such as energy depletion and oxidative stress, by Ca(2+)-entry, ceramide, caspases, calpain and/or altered activity of several kinases. Phosphatidylserine-exposing erythrocytes adhere to the vascular wall and may thus impede microcirculation. Eryptotic cells are further engulfed by phagocytes and thus rapidly cleared from circulation. Stimulation of eryptosis contributes to anemia of several clinical conditions such as metabolic syndrome, diabetes, malignancy, hepatic failure, heart failure, uremia, hemolytic uremic syndrome, sepsis, fever, dehydration, mycoplasma infection, malaria, iron deficiency, sickle cell anemia, thalassemia, glucose-6-phosphate dehydrogenase deficiency and Wilson's disease. On the other hand, eryptosis with subsequent clearance of infected erythrocytes in malaria may counteract parasitemia. In theory, anemia due to excessive eryptosis could be alleviated by treatment with small molecules inhibiting eryptosis. In malaria, stimulators of eryptosis may accelerate death of infected erythrocytes and thus favorably influence the clinical course of the disease. Many small molecules inhibit or stimulate eryptosis. Several stimulators favorably influence murine malaria. Further preclinical and subsequent clinical studies are required to elucidate the therapeutic potential of stimulators or inhibitors of eryptosis.

  10. Interactions of androgens, green tea catechins and the antiandrogen flutamide with the external glucose-binding site of the human erythrocyte glucose transporter GLUT1

    PubMed Central

    Naftalin, Richard J; Afzal, Iram; Cunningham, Philip; Halai, Mansur; Ross, Clare; Salleh, Naguib; Milligan, Stuart R

    2003-01-01

    This study investigates the effects of androgens, the antiandrogen flutamide and green tea catechins on glucose transport inhibition in human erythrocytes. These effects may relate to the antidiabetogenic effects of green tea. Testosterone, 4-androstene-3,17-dione, dehydroepiandrosterone (DHEA) and DHEA-3-acetate inhibit glucose exit from human erythrocytes with half-maximal inhibitions (Ki) of 39.2±8.9, 29.6±3.7, 48.1±10.2 and 4.8±0.98 μM, respectively. The antiandrogen flutamide competitively relieves these inhibitions and of phloretin. Dehydrotestosterone has no effect on glucose transport, indicating the differences between androgen interaction with GLUT1 and human androgen receptor (hAR). Green tea catechins also inhibit glucose exit from erythrocytes. Epicatechin 3-gallate (ECG) has a Ki ECG of 0.14±0.01 μM, and epigallocatechin 3-gallate (EGCG) has a Ki EGCG of 0.97±0.13 μM. Flutamide reverses these effects. Androgen-screening tests show that the green tea catechins do not act genomically. The high affinities of ECG and EGCG for GLUT1 indicate that this might be their physiological site of action. There are sequence homologies between GLUT1 and the ligand-binding domain (LBD) of hAR containing the amino-acid triads Arg 126, Thr 30 and Asn 288, and Arg 126, Thr 30 and Asn 29, with similar 3D topology to the polar groups binding 3-keto and 17-β OH steroid groups in hAR LBD. These triads are appropriately sited for competitive inhibition of glucose import at the external opening of the hydrophilic pore traversing GLUT1. PMID:12970085

  11. Effects of flaxseed oil on anti-oxidative system and membrane deformation of human peripheral blood erythrocytes in high glucose level

    PubMed Central

    2012-01-01

    Background The erythrocyte membrane lesion is a serious diabetic complication. A number of studies suggested that n-3 fatty acid could reduce lipid peroxidation and elevate α- or γ-tocopherol contents in membrane of erythrocytes. However, evidence regarding the protective effects of flaxseed oil, a natural product rich in n-3 fatty acid, on lipid peroxidation, antioxidative capacity and membrane deformation of erythrocytes exposed to high glucose is limited. Methods Human peripheral blood erythrocytes were isolated and treated with 50 mM glucose to mimic hyperglycemia in the absence or presence of three different doses of flaxseed oil (50, 100 or 200 μM) in the culture medium for 24 h. The malondialdehyde (MDA) and L-glutathione (GSH) were measured by HPLC and LC/MS respectively. The phospholipids symmetry and membrane fatty acid composition of human erythrocytes were detected by flow cytometry and gas chromatograph (GC). The morphology of human erythrocyte was illuminated by ultra scanning electron microscopy. Results Flaxseed oil attenuated hyperglycemia-induced increase of MDA and decrease of GSH in human erythrocytes. Human erythrocytes treated with flaxseed oil contained higher C22:5 and C22:6 than those in the 50 mM glucose control group, indicating that flaxseed oil could reduce lipid asymmetric distribution and membrane perturbation. The ultra scanning electron microscopy and flow cytometer have also indicated that flaxseed oil could protect the membrane of human erythrocytes from deformation at high glucose level. Conclusion The flaxseed oil supplementation may prevent lipid peroxidation and membrane dysfunction of human erythrocytes in hyperglycemia. PMID:22768971

  12. Accessibility of sulfhydryl residues induced by cytochalasin B binding and conformational dynamics in the human erythrocyte glucose transporter.

    PubMed

    Pinkofsky, H B; Jung, C Y

    1985-07-01

    Studies with intact cells have implicated essential sulfhydryl groups in the carrier-mediated glucose transport of human erythrocytes. In an attempt to identify and characterize such essential sulfhydryl residues we have studied the interaction of p-chloromercuribenzoate (PCMB) with a purified glucose transporter preparation (band 4.5) from human erythrocytes, in the presence and absence of its ligands, and the effects of this interaction on the binding of cytochalasin B (CB) to the transporter. At least 3 mol of PCMB reacted per mol of this preparation. A portion of the reaction was significantly enhanced in the presence of cytochalasin B. This enhancement was a saturable function of CB concentration, and was half-maximal at a CB concentration equal to the dissociation constant for the CB binding to the preparation. This CB-sensitive, PCMB reaction product comigrated with the band 4.5 on lithium dodecyl sulfate-polyacrylamide gel electrophoresis. An excess of D-glucose did not affect the PCMB reaction by itself in the absence of CB, but totally abolished the CB-induced enhancement of the PCMB reaction. PCMB inhibited the CB binding activity of the transporter preparation, and this inhibition was also enhanced in the presence of CB. These results suggest that CB binding perturbs the conformational dynamics of the glucose transporter resulting in an exposure of at least two sulfhydryl residues to PCMB reaction, and that some of these CB-sensitive sulfhydryl groups are essential for CB binding to the transporter.

  13. The impact of hemodialysis on erythrocyte membrane cytoskeleton proteins.

    PubMed

    Olszewska, Maria; Bober, Joanna; Wiatrow, Jerzy; Stępniewska, Joanna; Dołęgowska, Barbara; Chlubek, Dariusz

    2015-02-03

    Hemodialysis (HD) is one of the methods of renal replacement therapy, but it also contributes to an increase in oxidative stress. Hemodialysis leads to changes in the erythrocyte cytoskeleton structure, whilst the presence of glucose in the dialysis fluid which activates the pentose phosphate pathway contributes to the intensification of oxidative stress. Available literature lacks reports on the effect of glucose in the dialytic fluid on the composition of proteins of the cell membrane cytoskeleton. Red blood cells for this analysis were collected from patients with chronic renal failure treated with hemodialysis using both glucose-containing and glucose-free dialysis fluid. Following the preparation of membranes, the electrophoretic separation of proteins was performed in denaturing conditions according to Laemmli. The level of tryptophan in membranes was determined by spectrofluorimetry, whilst the activity of glucose-6-phosphate dehydrogenase was determined by measuring the reduction of oxidated NADP. Hemodialysis in both groups of patients resulted in a statistically significant reduction of tryptophan as an oxidative stress indicator when compared to the control group. Moreover, the activity of glucose-6-phosphate dehydrogenase in the group of patients was higher than in the control group, and following the HD procedure it decreased, which may have been caused by a reduced concentration of dialyzed glucose. The HD procedure affects the structure of the erythrocyte membrane cytoskeleton, which is reflected in the concentration changes in individual proteins and in their mutual relationships corresponding to vertical and horizontal interactions stabilizing the structure of the erythrocyte membrane cytoskeleton. These changes may contribute to the shortening of cell lifespan.

  14. Properties of N-maleoylmethionine sulphone, a novel impermeant maleimide, and its use in the selective labelling of the erythrocyte glucose-transport system.

    PubMed Central

    Roberts, S J; Tanner, M J; Denton, R M

    1982-01-01

    1. The synthesis of N-maleoylmethionine sulphone (MMS), a membrane-impermeant protein-labelling reagent, is described. Radioactively labelled MMS can be readily prepared at high specific radioactivity from [35S]methionine. 2. The permeability of the erythrocyte membrane to the reagent was assessed by determining the extent of inactivation of glyceraldehyde 3-phosphate dehydrogenase after treatment of erythrocytes with MMS. Some inactivation of this enzyme was found when high concentrations (20mM) of the compound were used, but this could be prevented by pretreatment of the erythrocytes with 4,4'-di-isothiocyanatostilbene-2,2'-disulphonic acid, suggesting that MMS slowly enters the cells via the anion-transport system. 3. Treatment of erythrocytes with [35S]MMS resulted in the labelling of six major components. Labelling of erythrocyte membranes resulted in the intense labelling of many additional components. 4. MMS inhibited erythrocyte glucose transport. Cytochalasin b protected glucose transport against inactivation by MMS. Labelling experiments in erythrocytes in the presence and in the absence of cytochalasin b showed that the cytochalasin b-protected material was a broad band in the band-4.5 region. Images Fig. 2. Fig. 3. Fig. 5. PMID:7126174

  15. Crystal Structure Analysis of Human Glutamine : Fructose 6-Phosphate Amidotransferase, a Key Regulator in Type 2 Diabetes

    NASA Astrophysics Data System (ADS)

    Nakaishi, Yuichiro; Bando, Masahiko

    Glutamine : fructose 6-phosphate amidotransferase (GFAT) is a rate-limiting enzyme in the hexoamine biosythetic pathway and plays an important role in type 2 diabetes. We now report the first structures of the isomerase domain of the human GFAT in the presence of cyclic glucose 6-phosphate and linear glucosamine 6-phosphate. The C-terminal tail including the active site displays a rigid conformation, similar to the corresponding Escherichia coli enzyme. The diversity of the CF helix near the active site suggests the helix is a major target for drug design. Our study provides insights into the development of therapeutic drugs for type 2 diabetes.

  16. G6PD Deficiency (Glucose-6-Phosphate Dehydrogenase) (For Parents)

    MedlinePlus

    ... trigger, is removed. In rare cases, G6PD deficiency leads to chronic anemia . With the right precautions, a child with G6PD deficiency can lead a healthy and active life. About G6PD Deficiency ...

  17. Genetics Home Reference: glucose-6-phosphate dehydrogenase deficiency

    MedlinePlus

    ... as some antibiotics and medications used to treat malaria). Hemolytic anemia can also occur after eating fava ... a G6PD mutation may be partially protected against malaria, an infectious disease carried by a certain type ...

  18. G6PD Deficiency (Glucose-6-Phosphate Dehydrogenase) (For Parents)

    MedlinePlus

    ... are high-risk areas for the infectious disease malaria . Researchers have found evidence that the parasite that ... deficiency may have developed as a protection against malaria. continue G6PD Deficiency Symptom Triggers Kids with G6PD ...

  19. Evidence for the coordinate control of glycogen synthesis, glucose utilization, and glycolysis in Escherichia coli. II. Quantitative correlation of the inhibition of glycogen synthesis and the stimulation of glucose utilization by 2,4-dinitrophenol with the effects on the cellular levels of glucose 6-phosphate, fructose, 1,6-diphosphate, and total adenylates.

    PubMed

    Dietzler, D N; Leckie, M P; Magnani, J L; Sughrue, M J; Bergstein, P E

    1975-09-25

    In cultures of Escherichia coli W4597(K) and G34 under various nutritional conditions the rates of glucose utilization and cellular levels of fructose-1,6-P2 are quantitatively related by the Hill equation where the value of the Hill coefficient is approximately equal to 2. This is the first evidence that fructose-P2, or any metabolite which covaries with fructose-P2, modulates glucose utilization in E. coli. In light of previous observations from our laboratory this new observation and those in the succeeding report provide the first evidence that in E. coli glycolsis, glycogen synthesis and glucose utilization are coordinately regulated, thus providing for the coupling of ATP utilization and production under various metabolic circumstances. Alterations in the level of ATP apparently affect the velocity of phosphofructokinase, the rate-limiting enzyme in glycolsis, altering the cellular levels of glucose-6-P or fructose-P2. Changes in the levels of these hexose phosphates are quantitatively related to alterations in the rates of glucose utilization and glycogen synthesis in the intact E. coli cell.

  20. Erythrocyte survival in sheep exposed to ozone

    SciTech Connect

    Moore, G.S.; Calabrese, E.J.; Labato, F.J.

    1981-07-01

    Erythrocyte survival studies in the Dorset ewe using chromium 51 were performed. The purpose of the study was to determine if ozone exposure produces decreased cell survival which may be the result of premature erythrocyte aging. This strain of sheep has an erythrocyte glucose-6-phosphate dehydrogenase (G6PD) activity that is very low, being comparable to human A-variants with G6PD deficiency. Ozone exposure may produce hemolytic effects in G6PD deficients more readily than in erythrocytes with normal activity. A decrease in hematocrit was observed in the ozone exposed groups. With respect to red cell destruction, ozone does not appear to act immediately, but rather there appears to be a delayed effect. At 0.25 ppM ozone, the group reached the 50% remaining level an average of 1 day sooner than the control group. There was no significant difference between control and exposed groups at the 0.50 ppM and 0.70 ppM levels. Also, the results demonstrate a net decrease in hematocrit which is greater for 0.25 ppM ozone than any other exposure level. (RJC)

  1. A new synthesis of sucrose 6'-phosphate.

    PubMed

    Kim, K B; Behrman, E J

    1995-04-18

    Sucrose 6'-phosphate (3) is the key intermediate for sucrose (1) synthesis in plants [1]. It has recently become commercially available at ca. $1500/g (Sigma). The only chemical synthesis is that of Buchanan et al. [2]. This six-step procedure, while unambiguous, gives an overall yield of only ca. 6%. We describe here a simplified route (2 steps) with an unoptimized yield of ca. 15%. Our strategy was to use a phosphorylation reagent selective for primary hydroxyl groups and thus to avoid the necessity for blocking all of the secondary ones. Sowa and Ouchi [3] described a suitable system which they used very effectively for the synthesis of 5'-nucleotides from unprotected nucleosides. We applied this reagent to 2,1':4,6-di-O-isopropylidenesucrose (2) [4] in which the only unprotected primary hydroxyl group is that at the 6'-position (Scheme 1). The identity of the product was established by comparison of its rotation with the literature value and by the correspondence of its 1H and 13C NMR spectra with those of an authentic sample synthesized by Buchanan's method (Sigma) 1H assignments were made with the help of the assignments of du Penhoat et al. [5] for sucrose and the results of a one-bond H-C COSY experiment (Fig. 1). The 13C spectrum showed that all of the resonances were shifted downfield by ca. 0.5 ppm as compared with sucrose [6] except for the C-5' doublet which was shifted upfield by 0.5 ppm and the C-6' doublet which was shifted downfield by 2.2 ppm (Table 1).

  2. Abnormal erythrocyte metabolism in hepatic disease.

    PubMed

    Smith, J R; Kay, N E; Gottlieb, A J; Oski, F A

    1975-12-01

    Erythrocyte (RBC) metabolic studies were done on 114 patients with severe hepatic disease. Heinz body formation after incubation of RBCs with acetyl phenylhydrazine was found to be significantly higher in patients than in controls. RBC-reduced glutathione levels were lower than those of controls both before and after incubation with acetyl phenylhydrazine, and patients with the highest Heinz body counts had the lowest reduced glutathione levels. RBC methylene blue-stimulated hexose monophosphate (HMP) shunt metabolism and glucose recycling through the shunt were significantly lower in patients with active hepatic disease than in controls. There was no difference in resting HMP shunt activity or in resting recycling of glucose. Despite impairment of shunt metabolism, total glucose consumption was greater in patients than in controls. The patients with the lowest stimulated HMP shunt metabolism and glucose recycling had the highest Heinz body counts, lowest reduced glutathione, and highest total glucose consumption. A continuum of abnormal shunt metabolism was seen, from a mild reduction of stimulated HMP shunt activity to a severe combined decrease in both the HMP shunt and glucose recycling. When measured, glutathione reductase, glutathione peroxidase, glucose-6-phosphate dehydrogenase, and transketolase were normal or increased. Sequential studies were done on 11 patients who had abnormal metabolic studies. Coincident with improvement of HMP shunt metabolism, the Heinz body counts became lower, reduced glutathione higher, hematocrit higher, and liver function improved. Impaired HMP shunt metabolism appears to be a common, acquired RBC abnormality in patients with severe, active liver disease.

  3. Dematin and Adducin Provide a Novel Link between the Spectrin Cytoskeleton and Human Erythrocyte Membrane by Directly Interacting with Glucose Transporter-1*S⃞

    PubMed Central

    Khan, Anwar A.; Hanada, Toshihiko; Mohseni, Morvarid; Jeong, Jong-Jin; Zeng, Lixiao; Gaetani, Massimiliano; Li, Donghai; Reed, Brent C.; Speicher, David W.; Chishti, Athar H.

    2008-01-01

    Dematin and adducin are actin-binding proteins located at the spectrin-actin junctions, also called the junctional complex, in the erythrocyte membrane. Here we propose a new model whereby dematin and adducin link the junctional complex to human erythrocyte plasma membrane. Using a combination of surface labeling, immunoprecipitation, and vesicle proteomics approaches, we have identified glucose transporter-1 as the receptor for dematin and adducin in the human erythrocyte membrane. This finding is the first description of a transmembrane protein that binds to dematin and adducin, thus providing a rationale for the attachment of the junctional complex to the lipid bilayer. Because homologues of dematin, adducin, and glucose transporter-1 exist in many non-erythroid cells, we propose that a conserved mechanism may exist that couples sugar and other related transporters to the actin cytoskeleton. PMID:18347014

  4. Dematin and adducin provide a novel link between the spectrin cytoskeleton and human erythrocyte membrane by directly interacting with glucose transporter-1.

    PubMed

    Khan, Anwar A; Hanada, Toshihiko; Mohseni, Morvarid; Jeong, Jong-Jin; Zeng, Lixiao; Gaetani, Massimiliano; Li, Donghai; Reed, Brent C; Speicher, David W; Chishti, Athar H

    2008-05-23

    Dematin and adducin are actin-binding proteins located at the spectrin-actin junctions, also called the junctional complex, in the erythrocyte membrane. Here we propose a new model whereby dematin and adducin link the junctional complex to human erythrocyte plasma membrane. Using a combination of surface labeling, immunoprecipitation, and vesicle proteomics approaches, we have identified glucose transporter-1 as the receptor for dematin and adducin in the human erythrocyte membrane. This finding is the first description of a transmembrane protein that binds to dematin and adducin, thus providing a rationale for the attachment of the junctional complex to the lipid bilayer. Because homologues of dematin, adducin, and glucose transporter-1 exist in many non-erythroid cells, we propose that a conserved mechanism may exist that couples sugar and other related transporters to the actin cytoskeleton.

  5. The effect of bilirubin on lipid peroxidation and antioxidant enzymes in cumene hydroperoxide-treated erythrocytes.

    PubMed

    Yeşilkaya, A; Yeğin, A; Ozdem, S; Aksu, T A

    1998-01-01

    Recently, it has been suggested that bilirubin may act as a potent biological chain-breaking antioxidant. To observe the effects of free bilirubin on antioxidant reactions in cumene hydroperoxide-treated erythrocytes (15 g hemoglobin/dl), we added bilirubin at four different concentrations (0.5, 1, 5, and 10 mg/dl). We measured the thiobarbituric acid-reactive substance and reduced glutathione levels, and some antioxidant enzyme activities, namely superoxide dismutase, catalase, and glucose-6-phosphate dehydrogenase. Thiobarbituric acid-reactive substance and chemiluminescent signals decreased during the incubation. Superoxide dismutase activities also decreased but not as much as in the control group. Glucose-6-phosphate dehydrogenase activities and reduced glutathione levels increased, but catalase activities remained the same as the control group. Our results suggest that bilirubin--in the concentrations we have used--partially prevented the oxidant effects of cumene hydroperoxide.

  6. The influence of Bauhinia forficata Link subsp. pruinosa tea on lipid peroxidation and non-protein SH groups in human erythrocytes exposed to high glucose concentrations.

    PubMed

    Salgueiro, Andréia C F; Leal, Carina Q; Bianchini, Matheus C; Prado, Ianeli O; Mendez, Andreas S L; Puntel, Robson L; Folmer, Vanderlei; Soares, Félix A; Avila, Daiana S; Puntel, Gustavo O

    2013-06-21

    Bauhinia forficata (BF) has been traditionally used as tea in folk medicine of Brazil for treatment of Diabetes mellitus (DM). To evaluate the effects of BF leaf tea on markers of oxidative damage and antioxidant levels in an experimental model of hyperglycemia in human erythrocytes in vitro. Human erythrocytes were incubated with high glucose concentrations or glucose and BF tea for 24h and 48h. After incubation lipid peroxidation and non-protein SH levels were analyzed. Moreover, quantification of polyphenols and flavonoids, iron chelating property, scavenging of DPPH, and prevention of lipid peroxidation in isolated lipids were also assessed. A significant amount of polyphenols and flavonoids was observed. The main components found by LC-MS analysis were quercetin-3-O-(2-rhamnosyl) rutinoside, kaempferol-3-O-(2-rhamnosyl) rutinoside, quercetin-3-O-rutinoside and kaempferol-3-O-rutinoside. BF tea presents important antioxidant and chelating properties. Moreover, BF tea was effective to increase non-protein SH levels and reduce lipid peroxidation induced by high glucose concentrations in human erythrocytes. The antioxidant effects of BF tea could be related to the presence of different phenolic and flavonoids components. We believe that these components can be responsible to protect human erythrocytes exposed to high glucose concentrations against oxidative damage. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  7. Triggers, Inhibitors, Mechanisms, and Significance of Eryptosis: The Suicidal Erythrocyte Death

    PubMed Central

    Lang, Elisabeth

    2015-01-01

    Suicidal erythrocyte death or eryptosis is characterized by erythrocyte shrinkage, cell membrane blebbing, and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include Ca2+ entry, ceramide formation, stimulation of caspases, calpain activation, energy depletion, oxidative stress, and dysregulation of several kinases. Eryptosis is triggered by a wide variety of xenobiotics. It is inhibited by several xenobiotics and endogenous molecules including NO and erythropoietin. The susceptibility of erythrocytes to eryptosis increases with erythrocyte age. Phosphatidylserine exposing erythrocytes adhere to the vascular wall by binding to endothelial CXC-Motiv-Chemokin-16/Scavenger-receptor for phosphatidylserine and oxidized low density lipoprotein (CXCL16). Phosphatidylserine exposing erythrocytes are further engulfed by phagocytosing cells and are thus rapidly cleared from circulating blood. Eryptosis eliminates infected or defective erythrocytes thus counteracting parasitemia in malaria and preventing detrimental hemolysis of defective cells. Excessive eryptosis, however, may lead to anemia and may interfere with microcirculation. Enhanced eryptosis contributes to the pathophysiology of several clinical disorders including metabolic syndrome and diabetes, malignancy, cardiac and renal insufficiency, hemolytic uremic syndrome, sepsis, mycoplasma infection, malaria, iron deficiency, sickle cell anemia, thalassemia, glucose 6-phosphate dehydrogenase deficiency, and Wilson's disease. Facilitating or inhibiting eryptosis may be a therapeutic option in those disorders. PMID:25821808

  8. Triggers, inhibitors, mechanisms, and significance of eryptosis: the suicidal erythrocyte death.

    PubMed

    Lang, Elisabeth; Lang, Florian

    2015-01-01

    Suicidal erythrocyte death or eryptosis is characterized by erythrocyte shrinkage, cell membrane blebbing, and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include Ca(2+) entry, ceramide formation, stimulation of caspases, calpain activation, energy depletion, oxidative stress, and dysregulation of several kinases. Eryptosis is triggered by a wide variety of xenobiotics. It is inhibited by several xenobiotics and endogenous molecules including NO and erythropoietin. The susceptibility of erythrocytes to eryptosis increases with erythrocyte age. Phosphatidylserine exposing erythrocytes adhere to the vascular wall by binding to endothelial CXC-Motiv-Chemokin-16/Scavenger-receptor for phosphatidylserine and oxidized low density lipoprotein (CXCL16). Phosphatidylserine exposing erythrocytes are further engulfed by phagocytosing cells and are thus rapidly cleared from circulating blood. Eryptosis eliminates infected or defective erythrocytes thus counteracting parasitemia in malaria and preventing detrimental hemolysis of defective cells. Excessive eryptosis, however, may lead to anemia and may interfere with microcirculation. Enhanced eryptosis contributes to the pathophysiology of several clinical disorders including metabolic syndrome and diabetes, malignancy, cardiac and renal insufficiency, hemolytic uremic syndrome, sepsis, mycoplasma infection, malaria, iron deficiency, sickle cell anemia, thalassemia, glucose 6-phosphate dehydrogenase deficiency, and Wilson's disease. Facilitating or inhibiting eryptosis may be a therapeutic option in those disorders.

  9. Streptococcus mutans serotype c tagatose 6-phosphate pathway gene cluster.

    PubMed Central

    Jagusztyn-Krynicka, E K; Hansen, J B; Crow, V L; Thomas, T D; Honeyman, A L; Curtiss, R

    1992-01-01

    DNA cloned into Escherichia coli K-12 from a serotype c strain of Streptococcus mutans encodes three enzyme activities for galactose utilization via the tagatose 6-phosphate pathway: galactose 6-phosphate isomerase, tagatose 6-phosphate kinase, and tagatose-1,6-bisphosphate aldolase. The genes coding for the tagatose 6-phosphate pathway were located on a 3.28-kb HindIII DNA fragment. Analysis of the tagatose proteins expressed by recombinant plasmids in minicells was used to determine the sizes of the various gene products. Mutagenesis of these plasmids with transposon Tn5 was used to determine the order of the tagatose genes. Tagatose 6-phosphate isomerase appears to be composed of 14- and 19-kDa subunits. The sizes of the kinase and aldolase were found to be 34 and 36 kDa, respectively. These values correspond to those reported previously for the tagatose pathway enzymes in Staphylococcus aureus and Lactococcus lactis. Images PMID:1328153

  10. ScrB (Cg2927) is a sucrose-6-phosphate hydrolase essential for sucrose utilization by Corynebacterium glutamicum.

    PubMed

    Engels, Verena; Georgi, Tobias; Wendisch, Volker F

    2008-12-01

    Corynebacterium glutamicum can grow on a variety of carbohydrates from which glucose, fructose and sucrose are taken up and phosphorylated by the phosphoenolpyruvate-dependent phosphotransferase system (PTS). Here, we show that cg2927 (scrB) encodes sucrose-6-phosphate hydrolase. The purified His-tagged protein hydrolyzed sucrose-6-phosphate and sucrose, but not sucrose-6'-phosphate. The Km value for sucrose was 190 mM while the Km for sucrose-6-phosphate was much lower, 0.04 mM. Sucrose-6-phosphate hydrolase activity was stimulated by MgSO4 and fructose-6-phosphate and was inhibited by MnCl2, CaCl2, CuSO4 and ZnSO4. A scrB deletion mutant could not grow on sucrose as the sole carbon source. In addition, growth in the absence of scrB was severely decreased when sucrose was present in addition to glucose, fructose or acetate, suggesting that higher intracellular concentrations of sucrose-6-phosphate are toxic. Transcriptional start sites in the cg2929-cg2928-scrB-ptsS locus could be revealed upstream of cg2929 and upstream of the sucrose-specific PTS gene ptsS. Of these, only ptsS showed increased expression when grown in the presence of sucrose, which was due to control by the transcriptional regulator SugR. The sucrose-6-phosphate hydrolase activity, however, was increased two- to threefold during growth in fructose- or sucrose-containing media, regardless of the presence or absence of SugR.

  11. Inhibition of Recombinant Aldose-6-Phosphate Reductase from Peach Leaves by Hexose-Phosphates, Inorganic Phosphate and Oxidants.

    PubMed

    Hartman, Matías D; Figueroa, Carlos M; Arias, Diego G; Iglesias, Alberto A

    2017-01-01

    Glucitol, also known as sorbitol, is a major photosynthetic product in plants from the Rosaceae family. This sugar alcohol is synthesized from glucose-6-phosphate by the combined activities of aldose-6-phosphate reductase (Ald6PRase) and glucitol-6-phosphatase. In this work we show the purification and characterization of recombinant Ald6PRase from peach leaves. The recombinant enzyme was inhibited by glucose-1-phosphate, fructose-6-phosphate, fructose-1,6-bisphosphate and orthophosphate. Oxidizing agents irreversibly inhibited the enzyme and produced protein precipitation. Enzyme thiolation with oxidized glutathione protected the enzyme from insolubilization caused by diamide, while incubation with NADP+ (one of the substrates) completely prevented enzyme precipitation. Our results suggest that Ald6PRase is finely regulated to control carbon partitioning in peach leaves. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  12. N-Acetylation of Glucosamine-6-Phosphate in Leuconostoc mesenteroides

    PubMed Central

    DeMoss, R. D.; Moser, K.

    1969-01-01

    A partially purified enzyme (120-fold) from Leuconostoc mesenteroides catalyzed the reversible N-acetylation of d-glucosamine-6-phosphate. Coenzyme A was not required and inhibited the reaction rate. Neither d-glucosamine nor N-acetyl-d-glucosamine served as a substrate for the reversible reaction. The enzyme preparation retained 50% of its original activity after 5 min at 100 C. The Km for acetate was 7.7 × 10−2m in the presence of 2 × 10−2md-glucosamine-6-phosphate. The Km for d-glucosamine-6-phosphate was 5.0 × 10−3m in the presence of 0.64 m acetate. The product of the reaction was characterized by comparison with N-acetyl-d-glucosamine-6-phosphate prepared by enzymatic phosphorylation of N-acetyl-d-glusamine. The characterization tests were: chromatographic migration, acid hydrolysis, enzymatic dephosphorylation, sodium borohydride reduction, and periodate oxidation. The equilibrium constant for the reaction was about 7.5 m for the expression K = (d-glucosamine-6-phosphate)(acetate)/N-acetyl-d-glucosamine-6-phosphate. The standard free energy of the reaction was approximately 1,200 cal per mole. PMID:5781575

  13. Structural Basis for Morpheein-type Allosteric Regulation of Escherichia coli Glucosamine-6-phosphate Synthase

    PubMed Central

    Mouilleron, Stéphane; Badet-Denisot, Marie-Ange; Pecqueur, Ludovic; Madiona, Karine; Assrir, Nadine; Badet, Bernard; Golinelli-Pimpaneau, Béatrice

    2012-01-01

    The amino-terminal cysteine of glucosamine-6-phosphate synthase (GlmS) acts as a nucleophile to release and transfer ammonia from glutamine to fructose 6-phosphate through a channel. The crystal structure of the C1A mutant of Escherichia coli GlmS, solved at 2.5 Å resolution, is organized as a hexamer, where the glutaminase domains adopt an inactive conformation. Although the wild-type enzyme is active as a dimer, size exclusion chromatography, dynamic and quasi-elastic light scattering, native polyacrylamide gel electrophoresis, and ultracentrifugation data show that the dimer is in equilibrium with a hexameric state, in vitro and in cellulo. The previously determined structures of the wild-type enzyme, alone or in complex with glucosamine 6-phosphate, are also consistent with a hexameric assembly that is catalytically inactive because the ammonia channel is not formed. The shift of the equilibrium toward the hexameric form in the presence of cyclic glucosamine 6-phosphate, together with the decrease of the specific activity with increasing enzyme concentration, strongly supports product inhibition through hexamer stabilization. Altogether, our data allow us to propose a morpheein model, in which the active dimer can rearrange into a transiently stable form, which has the propensity to form an inactive hexamer. This would account for a physiologically relevant allosteric regulation of E. coli GlmS. Finally, in addition to cyclic glucose 6-phosphate bound at the active site, the hexameric organization of E. coli GlmS enables the binding of another linear sugar molecule. Targeting this sugar-binding site to stabilize the inactive hexameric state is therefore suggested for the development of specific antibacterial inhibitors. PMID:22851174

  14. Bacillus licheniformis trehalose-6-phosphate hydrolase structures suggest keys to substrate specificity.

    PubMed

    Lin, Min Guan; Chi, Meng Chun; Naveen, Vankadari; Li, Yi Ching; Lin, Long Liu; Hsiao, Chwan Deng

    2016-01-01

    Trehalose-6-phosphate hydrolase (TreA) belongs to glycoside hydrolase family 13 (GH13) and catalyzes the hydrolysis of trehalose 6-phosphate (T6P) to yield glucose and glucose 6-phosphate. The products of this reaction can be further metabolized by the energy-generating glycolytic pathway. Here, crystal structures of Bacillus licheniformis TreA (BlTreA) and its R201Q mutant complexed with p-nitrophenyl-α-D-glucopyranoside (R201Q-pPNG) are presented at 2.0 and 2.05 Å resolution, respectively. The overall structure of BlTreA is similar to those of other GH13 family enzymes. However, detailed structural comparisons revealed that the catalytic site of BlTreA contains a long loop that adopts a different conformation from those of other GH13 family members. Unlike the homologous regions of Bacillus cereus oligo-1,6-glucosidase (BcOgl) and Erwinia rhapontici isomaltulose synthase (NX-5), the surface potential of the BlTreA active site exhibits a largely positive charge contributed by the four basic residues His281, His282, Lys284 and Lys292. Mutation of these residues resulted in significant decreases in the enzymatic activity of BlTreA. Strikingly, the (281)HHLK(284) motif and Lys292 play critical roles in substrate discrimination by BlTreA.

  15. Comparative erythrocyte metabolism in marsupials and monotremes.

    PubMed

    Parkinson, A L; Whittington, A T; Spencer, P B; Grigg, G; Hinds, L; Gallagher, C; Kuchel, P; Agar, N S

    1995-03-01

    Concentrations of ATP and DPG, activities of 10 enzymes and the glycolytic rates were measured in the erythrocytes of 11 species of marsupials and two species of monotremes. Mean DPG concentrations were greater in the erythrocytes of marsupials than those of eutherian mammals. The opposite is true of ATP. Significant findings from the results of enzyme activities were: high activity of hexokinase (7.39 +/- 0.82 EU/g Hb) in the short-beaked echidna, pyruvate kinase (37.49 +/- 1.0 EU/g) Hb in bridled nailtail wallaby and glucose-6-phosphate dehydrogenase (G6PD; 41.66 +/- 1.24 EU/g Hb) in black-striped wallaby. About 6- to 7-fold difference in the activity of G6PD levels between the two species of wombats was confirmed. Glucose phosphate isomerase activity was also shown to be twice as high in the red cells of the common wombat compared with those of the southern hairy nosed wombat. There were wide variations in the glycolytic rate among the species examined.

  16. Cation channels, cell volume and the death of an erythrocyte.

    PubMed

    Lang, Florian; Lang, Karl S; Wieder, Thomas; Myssina, Svetlana; Birka, Christina; Lang, Philipp A; Kaiser, Stephanie; Kempe, Daniela; Duranton, Christophe; Huber, Stephan M

    2003-11-01

    Similar to a variety of nucleated cells, human erythrocytes activate a non-selective cation channel upon osmotic cell shrinkage. Further stimuli of channel activation include oxidative stress, energy depletion and extracellular removal of Cl-. The channel is permeable to Ca2+ and opening of the channel increases cytosolic [Ca2+]. Intriguing evidence points to a role of this channel in the elimination of erythrocytes by apoptosis. Ca2+ entering through the cation channel stimulates a scramblase, leading to breakdown of cell membrane phosphatidylserine asymmetry, and stimulates Ca(2+)-sensitive K+ channels, thus leading to KCl loss and (further) cell shrinkage. The breakdown of phosphatidylserine asymmetry is evidenced by annexin binding, a typical feature of apoptotic cells. The effects of osmotic shock, oxidative stress and energy depletion on annexin binding are mimicked by the Ca2+ ionophore ionomycin (1 microM) and blunted in the nominal absence of extracellular Ca2+. Nevertheless, the residual annexin binding points to additional mechanisms involved in the triggering of the scramblase. The exposure of phosphatidylserine at the extracellular face of the cell membrane stimulates phagocytes to engulf the apoptotic erythrocytes. Thus, sustained activation of the cation channels eventually leads to clearance of affected erythrocytes from peripheral blood. Susceptibility to annexin binding is enhanced in several genetic disorders affecting erythrocyte function, such as thalassaemia, sickle-cell disease and glucose-6-phosphate dehydrogenase deficiency. The enhanced vulnerability presumably contributes to the shortened life span of the affected erythrocytes. Beyond their role in the limitation of erythrocyte survival, cation channels may contribute to the triggering of apoptosis in nucleated cells exposed to osmotic shock and/or oxidative stress.

  17. Glucose metabolism is accelerated by exposure to t-butylhydroperoxide during NADH consumption in human erythrocytes.

    PubMed

    Ogasawara, Yuki; Funakoshi, Masayo; Ishii, Kazuyuki

    2008-01-01

    Several mechanisms have been proposed to underlie the events that occur during oxidative damage in red blood cells (RBCs) exposed to reactive oxygen species. This work explores what happens when metabolites related to redox regulation in human RBCs are oxidized to form alkoxyl radical and peroxyl radical as a result of exposure to tert-buthylhydroperoxide (BHP). During exposure to BHP, the glutathione level and the ratio of NADPH to total nicotinamide adenine dinucleotide phosphate (NADPH plus NADP(+)) were significantly decreased. Although alteration in the concentration of monosaccharides metabolized in the pentose phosphate pathway (PPP) was not observed, exposing RBCs to BHP caused the formation of methemoglobin (metHb) and a significant decrease in NADH. Moreover, we detected a significant increase in one of the peaks during BHP exposure by using HPLC with dansyl hydrazine as a prelabel reagent. A complete enzymatic conversion procedure was used to identify the peak as pyruvate based on comparison with standards. These results suggest that the rapid recovery in the level of glutathione and the formation of metHb by BHP require NADPH and NADH consumption. Subsequently, glucose metabolism accelerates to reproduce NADPH and NADH, which results in pyruvate accumulation. Our findings indicate that the level of pyruvate markedly increases upon exposure to a radical-generating oxidant capable of forming metHb. Methemoglobin reductase requires NADH as a co-factor, and oxidized form (NHADP(+)) is reduced via the glycolytic reaction catalyzed by glyceraldehyde 3-phosphate dehydrogenase. Thus, the overall acceleration of glycolysis induced by BHP is strongly dependent on the NADH reproducing pathway. In addition, the decrease in NADH enhances the increase in pyruvate by inhibiting the conversion of pyruvate to lactate in the presence of lactate dehydrogenase.

  18. Erythrocyte oxidative stress markers in children with sickle cell disease.

    PubMed

    Hermann, Priscila Bacarin; Pianovski, Mara Albonei Dudeque; Henneberg, Railson; Nascimento, Aguinaldo José; Leonart, Maria Suely Soares

    2016-01-01

    To determine eight parameters of oxidative stress markers in erythrocytes from children with sickle cell disease and compare with the same parameters in erythrocytes from healthy children, since oxidative stress plays an important role in the pathophysiology of sickle cell disease and because this disease is a serious public health problem in many countries. Blood samples were obtained from 45 children with sickle cell disease (21 males and 24 females with a mean age of 9 years; range: 3-13 years) and 280 blood samples were obtained from children without hemoglobinopathies (137 males and 143 females with a mean age of 10 years; range: 8-11 years), as a control group. All blood samples were analyzed for methemoglobin, reduced glutathione, thiobarbituric acid reactive substances, percentage of hemolysis, reactive oxygen species, and activity of the enzymes glucose 6-phosphate dehydrogenase, superoxide dismutase, and catalase. Data were analyzed using Student's t-test and were expressed as the mean±standard deviation. A p-value of <0.05 was considered significant. Significant differences were observed between children with sickle cell disease and the control group for the parameters methemoglobin, thiobarbituric acid reactive substances, hemolysis, glucose 6-phosphate dehydrogenase activity, and reactive oxygen species, with higher levels in the patients than in the controls. Oxidative stress parameters in children's erythrocytes were determined using simple laboratory methods with small volumes of blood; these biomarkers can be useful to evaluate disease progression and outcomes in patients. Copyright © 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  19. Sulphurous mineral water oral therapy: effects on erythrocyte metabolism.

    PubMed

    Albertini, Maria Cristina; Teodori, Laura; Accorsi, Augusto; Soukri, Abdelaziz; Campanella, Luigi; Baldoni, Francesco; Dachà, Marina

    2008-10-01

    The ingestion of water containing hydrogen sulphide (H(2)S) is common in spring sulphurous mineral water (SMW) therapy. We hypothesized that observed detrimental effects are related to the alteration of erythrocytes metabolism caused by H(2)S. To verify our hypothesis, we treated 20 healthy volunteers with SMW and evidenced an increase of methemoglobin concentration, an inhibition of both erythrocyte glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and glucose-6-phosphate dehydrogenase (G6PDH) activities. To investigate the mechanism of H(2)S effect on GAPDH activity, an in vitro study was performed by incubating both erythrocytes from 12 healthy volunteers and purified GAPDH with buffered [(35)S]-H(2)S labelled sulphurous water. The interaction between H(2)S and NAD(+)(H), was also investigated. The results indicate that a direct reaction between GAPDH and H(2)S does not occur and the observed decrease of GAPDH activity is to ascribe to the reaction between H(2)S and NAD(+)(H). This may lead to GAPDH inhibition by two ways, namely (i) cellular NAD(+)(H) reduced availability and (ii) catalytic site blockage. In conclusion, our results show that among the detrimental effects of SMW administration are erythrocyte GAPDH and G6PDH activity inhibition and increased methemoglobin concentration. A mechanism to explain the occurrence of these biochemical events is also proposed.

  20. Ceramide in the regulation of eryptosis, the suicidal erythrocyte death.

    PubMed

    Lang, Elisabeth; Bissinger, Rosi; Gulbins, Erich; Lang, Florian

    2015-05-01

    Similar to apoptosis of nucleated cells, erythrocytes may undergo eryptosis, a suicidal death characterized by cell shrinkage and phospholipid scrambling of the cell membrane leading to phosphatidylserine exposure at the cell surface. As eryptotic erythrocytes are rapidly cleared from circulating blood, excessive eryptosis may lead to anemia. Moreover, eryptotic erythrocytes may adhere to the vascular wall and thus impede microcirculation. Stimulators of eryptosis include osmotic shock, oxidative stress and energy depletion. Mechanisms involved in the stimulation eryptosis include ceramide formation which may result from phospholipase A2 dependent formation of platelet activating factor (PAF) with PAF dependent stimulation of sphingomyelinases. Enhanced erythrocytic ceramide formation is observed in fever, sepsis, HUS, uremia, hepatic failure, and Wilson's disease. Enhanced eryptosis is further observed in iron deficiency, phosphate depletion, dehydration, malignancy, malaria, sickle-cell anemia, beta-thalassemia and glucose-6-phosphate dehydrogenase-deficiency. Moreover, eryptosis is triggered by osmotic shock and a wide variety of xenobiotics, which are again partially effective by enhancing ceramide abundance. Ceramide formation is inhibited by high concentrations of urea. As shown in Wilson's disease, pharmacological interference with ceramide formation may be a therapeutic option in the treatment of eryptosis inducing clinical disorders.

  1. Catalase and glutathione peroxidase are equally active in detoxification of hydrogen peroxide in human erythrocytes

    SciTech Connect

    Gaetani, G.F.; Galiano, S.; Canepa, L.; Ferraris, A.M.; Kirkman, H.N.

    1989-01-01

    Genetic deficiencies of glucose-6-phosphate dehydrogenase (G6PD) and NADPH predispose affected erythrocytes to destruction from peroxides. Conversely, genetic deficiencies of catalase do not predispose affected erythrocytes to peroxide-induced destruction. These observations have served to strengthen the assumption that the NADPH/glutathione/glutathione peroxidase pathway is the principal means for disposal of H/sub 2/O/sub 2/ in human erythrocytes. Recently, however, mammalian catalase was found to have tightly bound NADPH and to require NADPH for the prevention and reversal of inactivation by its toxic substrate (H/sub 2/O/sub 2/). Since both catalase and the glutathione pathway are dependent on NADPH for function, this finding raises the possibility that both mechanisms destroy H/sub 2/O/sub 2/ in human erythrocytes. A comparison of normal and acatalasemic erythrocytes in the present study indicated that catalase accounts for more than half of the destruction of H/sub 2/O/sub 2/ when H/sub 2/O/sub 2/ is generated at a rate comparable to that which leads to hemolysis in G6PD- deficient erythrocytes.

  2. Antioxidant status of erythrocytes and their response to oxidative challenge in humans with argemone oil poisoning

    SciTech Connect

    Babu, Challagundla K.; Khanna, Subhash K.; Das, Mukul

    2008-08-01

    Oxidative damage of biomolecules and antioxidant status in erythrocytes of humans from an outbreak of argemone oil (AO) poisoning in Kannauj (India) and AO intoxicated experimental animals was investigated. Erythrocytes of the dropsy patients and AO treated rats were found to be more susceptible to 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) induced peroxidative stress. Significant decrease in RBC glutathione (GSH) levels (46, 63%) with concomitant enhancement in oxidized glutathione (172, 154%) levels was noticed in patients and AO intoxicated animals. Further, depletion of glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G-6-PDH) and glutathione-S-transferase (GST) (42-52%) was observed in dropsy patients. Oxidation of erythrocyte membrane lipids and proteins was increased (120-144%) in patients and AO treated animals (112-137%) along with 8-OHdG levels in whole blood (180%) of dropsy patients. A significant reduction in {alpha}-tocopherol content (68%) was noticed in erythrocytes of dropsy patients and hepatic, plasma and RBCs of AO treated rats (59-70%) thereby indicating the diminished antioxidant potential to scavenge free radicals or the limited transport of {alpha}-tocopherol from liver to RBCs leading to enhanced oxidation of lipids and proteins in erythrocytes. These studies implicate an important role of erythrocyte degradation in production of anemia and breathlessness in epidemic dropsy.

  3. Interactions of ATP, oestradiol, genistein and the anti-oestrogens, faslodex (ICI 182780) and tamoxifen, with the human erythrocyte glucose transporter, GLUT1.

    PubMed Central

    Afzal, Iram; Cunningham, Philip; Naftalin, Richard J

    2002-01-01

    17 beta-Oestradiol (ED when subscript to K) and the phytoestrogen isoflavone genistein (GEN) inhibit glucose transport in human erythrocytes and erythrocyte ghosts. The selective oestrogen receptor modulators or anti-oestrogens, faslodex (ICI 182780) (FAS) and tamoxifen (TAM), competitively antagonize oestradiol inhibition of glucose exit from erythrocytes (K(i(ED/FAS))=2.84+/-0.16 microM and K(i(ED/TAM))=100+/-2 nM). Faslodex has no significant inhibitory effect on glucose exit, but tamoxifen alone inhibits glucose exit (K(i(TAM))=300+/-100 nM). In ghosts, ATP (1-4 mM) competitively antagonizes oestradiol, genistein and cytochalasin B (CB)-dependent inhibitions of glucose exit, (K(i(ATP/ED))=2.5+/-0.23 mM, K(i(ATP/GEN))=0.99+/-0.17 mM and K(i(ATP/CB))=0.76+/-0.08 mM). Tamoxifen and faslodex reverse oestradiol-dependent inhibition of glucose exit with ATP>1 mM (K(i(ED/TAM))=130+/-5 nM and K(i(ED/FAS))=2.7+/-0.9 microM). The cytoplasmic surface of the glucose transporter (GLUT)1 contains four sequences with close homologies to sequences in the ligand-binding domain of human oestrogen receptor beta (hesr-2). One homology is adjacent to the Walker ATP-binding motif II (GLUT1, residues 225-229) in the large cytoplasmic segment linking transmembrane helices 6 and 7; another GLUT (residues 421-423) contains the Walker ATP-binding motif III. Mapping of these regions on to a three-dimensional template of GLUT indicates that a possible oestrogen-binding site lies between His(337), Arg(349) and Glu(249) at the cytoplasmic entrance to the hydrophilic pore spanning GLUT, which have a similar topology to His(475), Glu(305) and Arg(346) in hesr-2 that anchor the head and tail hydroxy groups of oestradiol and genistein, and thus are suitably placed to provide an ATP-sensitive oestrogen binding site that could modulate glucose export. PMID:12133004

  4. Comparative Study of Erythrocyte Glycolytic Enzymes in Man and in Two Species of Lagomorphae

    PubMed Central

    Puget, A.; Gouarderes, Christine; Vergnes, H.

    1974-01-01

    The authors made a comparative study of red cell enzyme glycolysis in man and in two species of Lagomorphae, the pika and the rabbit. The activities of the 12 enzymes of Embden-Meyerhoff pathway and of the two dehydrogenases of pentose shunt (glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase) were determined. Phosphoglycerate kinase and pyruvate kinase showed quite similar activities in pika erythrocytes and in erythrocytes from human umbilical cord. The levels of these enzymes differed significantly in the pika and in the rabbit. No differences were noted between pyruvate kinases from the rabbit and the neonatal man. The other activities gave values either identical to those found in the adult man or intermediate between the adult and the neonatal man. In the rabbit the levels of glycolitic enzymes were generally lower than in the pika except for lactate dehydrogenase and glycose-6-phosphate dehydrogenase. Some characteristics of erythrocyte metabolism specific to the pika may account for the differences observed in this species. The influence of red cell age cannot explain the variations observed for no significant reticulocytosis was observed in the circulating blood. The percentages found in the pika and the rabbit were essentially identical at determination. PMID:4277413

  5. Sodium Nitrate Induces Reactive Oxygen Species That Lower the Antioxidant Power, Damage the Membrane, and Alter Pathways of Glucose Metabolism in Human Erythrocytes.

    PubMed

    Ansari, Fariheen Aisha; Mahmood, Riaz

    2015-12-09

    Nitrate salts are widely used as food additives and nitrogenous fertilizers and are present as contaminants in drinking water supplies. The effect of different concentrations (1-15 mM) of sodium nitrate (NaNO3) on human erythrocytes was studied under in vitro conditions. Treatment of erythrocytes with NaNO3 resulted in increases in methemoglobin levels, lipid peroxidation, and protein oxidation and a decrease in glutathione content. There were changes in the activities of all major antioxidant defense enzymes, and the pathways of glucose metabolism were also affected. Increased generation of reactive oxygen species (ROS) took place while the antioxidant power was impaired. The osmotic fragility of cells was increased, and membrane-bound enzymes were greatly inhibited. All changes were statistically significant at a probability level of P < 0.05 at all concentrations of NaNO3 except the lowest (1 mM). Thus, NaNO3 generates ROS that cause significant damage to human erythrocytes and interfere in normal cellular pathways.

  6. Cytochalasin B binding proteins in human erythrocyte membranes. Modulation of glucose sensitivity by site interaction and partial solubilization of binding activities.

    PubMed

    Pinkofsky, H B; Rampal, A L; Cowden, M A; Jung, C Y

    1978-07-25

    We have previously described three different cytochalasin B binding sites in human erythrocyte membranes, a D-glucose-sensitive site (Site I), a cytochalasin E-sensitive site (Site II), and a site (Site III) insensitive to both D-glucose and cytochalasin E. Ligand bindings to each of these sites were considered to be independent (Jung, C., and Rampal, A. (1977) J. Biol. Chem. 252, 5456-5463). However, we have obtained subsequently the following evidence which indicated that an interaction occurs between Sites II and III, and this modulates sensitivity of Site III to the sugar. The displacement of cytochalasin E greatly exceeds the sum of their independent displacements. This ghosts extracted with EDTA or 2,3-dimethylmaleic anhydride at low ionic strength lack Site II activity but retain Site I and III activities, and both of these activities are displaceable by D-glucose alone. This indicated that the removal of Site II from the membrane confers glucose sensitivity to Site III. These observations are consistent with a model that Sites II and III in the membrane exist in a close association through which unliganded Site II maintains the glucose insensitivity of Site III, and once site II is liganded or removed by extraction this association is disrupted and Site III becomes glucose-sensitive. The ghosts extracted with Triton X-100 retain a cytochalasin B binding activity similar to that of site II (Kd = 1.8 X 10(-7) M, cytochalasin E-sensitive, glucose-insensitive), whereas a binding activity similar to that of Site I (Kd = 4 X 10(-7) M, cytochalasin E-insensitive, glucose-sensitive) is recovered in the Triton extract. A cytochalasin B binding activity similar to that of Site II is solubilized by EDTA at low ionic strength.

  7. Erythrocyte catalase inactivation (H2O2 production) by ascorbic acid and glucose in the presence of aminotriazole: role of transition metals and relevance to diabetes.

    PubMed Central

    Ou, P; Wolff, S P

    1994-01-01

    Erythrocytes exposed to ascorbic acid in the presence of aminotriazole undergo a dose- and time-dependent inactivation of endogenous catalase which is proportional to environmental hydrogen peroxide (H2O2) concentrations. The production of H2O2 seems to be dependent upon the availability of transition metal chelatable by o-phenanthroline (OPT), although the kinetics of catalase inactivation and H2O2 production by externally added copper ions in the presence of OPT is complex. Furthermore, although glucose is also able to undergo a transition-metal-catalysed oxidation yielding H2O2, the production of H2O2 by glucose seems to be a minor process by comparison with ascorbic acid oxidation. Indeed, on the basis of these data, transition-metal-catalysed ascorbic acid oxidation is likely to be a more important source of oxidative stress in the diabetic state than hyperglycaemia. PMID:7980465

  8. Studies on the oxidation–reduction systems of the erythrocyte

    PubMed Central

    Sánchez De Jiménez, Estela; Torres, J.; Valles, Victoria E.; Solís, J.; Soberón, G.

    1965-01-01

    1. Starvation for 3 days produces a decrease in methaemoglobin-reductase and glutathione-reductase activities, but it does not alter the glucose 6-phosphate-dehydrogenase activity of the rat erythrocyte. 2. The feeding of a protein-free diet for 11 days causes greater changes in the first two enzymes and also a diminution of the third. Under this experimental condition slight decreases in protein and haemoglobin contents were noted. 3. The experimental animals did not show methaemoglobinaemia, probably because the activity of methaemoglobin diaphorase is preserved. 4. The GSH content was not affected but the stability of the tripeptide in the presence of an oxidizing agent was diminished. PMID:4379799

  9. Mechanisms and pathophysiological significance of eryptosis, the suicidal erythrocyte death.

    PubMed

    Lang, Elisabeth; Lang, Florian

    2015-03-01

    Eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and cell membrane scrambling, is stimulated by Ca(2+) entry through Ca(2+)-permeable, PGE2-activated cation channels, by ceramide, caspases, calpain, complement, hyperosmotic shock, energy depletion, oxidative stress, and deranged activity of several kinases (e.g. AMPK, GK, PAK2, CK1α, JAK3, PKC, p38-MAPK). Eryptosis is triggered by intoxication, malignancy, hepatic failure, diabetes, chronic renal insufficiency, hemolytic uremic syndrome, dehydration, phosphate depletion, fever, sepsis, mycoplasma infection, malaria, iron deficiency, sickle cell anemia, thalassemia, glucose 6-phosphate dehydrogenase deficiency, and Wilson's disease. Eryptosis may precede and protect against hemolysis but by the same token result in anemia and deranged microcirculation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Acute consumption of organic and conventional tropical grape juices (Vitis labrusca L.) increases antioxidants in plasma and erythrocytes, but not glucose and uric acid levels, in healthy individuals.

    PubMed

    Toaldo, Isabela Maia; Cruz, Fernanda Alves; da Silva, Edson Luiz; Bordignon-Luiz, Marilde T

    2016-08-01

    Bioactive polyphenols in grapes are influenced by grape variety and cultivation conditions. The Vitis labrusca L. varieties are cultivated in tropical regions and used for grape juice production. We hypothesized that polyphenols from tropical grape juices would beneficially affect redox homeostasis in humans. Therefore, the effects of acute consumption of organic and conventional grape juices from V labrusca L. on antioxidants biomarkers were investigated in healthy individuals. In a controlled, randomized, crossover, intervention trial, 24 individuals were assigned to drink 400 mL of conventional juice, organic juice, or water. Each intervention was followed by a 14-day washout period. Blood samples were obtained before and 1 hour after acute intake and analyzed for erythrocyte reduced glutathione, serum total antioxidant capacity, antioxidant enzymes in erythrocytes, and glucose and uric acid in serum. The ingestion of both grape juices resulted in elevated levels of reduced glutathione (P< .001) and serum total antioxidant capacity (P< .05) and increased activity of catalase (P< .001), superoxide dismutase (P< .001), and glutathione peroxidase (P< .05) compared with the control intervention, with no significant differences between grape juices (P< .05). The intake of juices did not affect significantly the concentrations of glucose or uric acid. Grape juice polyphenols were associated with increased antioxidants, and the chemical differences between organic and conventional juices were not predictive of the observed responses. The results suggest a bioactive potential of V labrusca L. juices to improve redox homeostasis, which is involved in defense against oxidative stress in humans.

  11. Erythrocyte Glutathione Depletion Impairs Resistance to Haemolysis in Women Consuming Alcohol

    PubMed Central

    Padmini, Ekambaram; Sundari, Balasubramaniam Thiripura

    2008-01-01

    Alcohol abuse is known to cause an array of ethanol induced abnormalities in men but very few reports are available on the effect of alcohol in women. None of them discuss the effect of ethanol consumption on erythrocyte membrane. In the present study, erythrocytes in women who consume alcohol showed significant decrease in their ability to resist haemolysis with HPLC studies. Erythrocyte membrane indicates decreased phospholipid (p<0.05) levels, which increased the cholesterol/phospholipid ratio significantly (p<0.01) in women who consume alcohol. This can decrease the fluidity of membrane, which appears to be related to the effect of ethanol on erythrocyte membrane. Also the protection against exogenous and endogenous peroxides in the erythrocytes of alcoholic women is considerably affected due to decreased (p<0.05) activity of catalase, glucose-6-phosphate dehydrogenase, protein–SH group and glutathione (GSH). Enhanced free radical generation induced oxidation of oxyHb to metHb in alcoholics. Increased methemoglobin leads to significant reduction in membrane GSH, which may cause protein thiol oxidation. Thus peroxidative damage to membrane lipids and oxidation of membrane protein thiols potentially harmful to membrane fluidity and flexibility is responsible for decreased resistance to haemolysis as demonstrated in women who consume alcohol. PMID:18231625

  12. Characterization of a Mannose-6-Phosphate Isomerase from Bacillus amyloliquefaciens and Its Application in Fructose-6-Phosphate Production

    PubMed Central

    Sigdel, Sujan; Singh, Ranjitha; Kim, Tae-Su; Li, Jinglin; Kim, Sang-Yong; Kim, In-Won; Jung, Woo-Suk; Pan, Cheol-Ho; Kang, Yun Chan; Lee, Jung-Kul

    2015-01-01

    The BaM6PI gene encoding a mannose-6-phosphate isomerase (M6PI, EC 5.3.1.8) was cloned from Bacillus amyloliquefaciens DSM7 and overexpressed in Escherichia coli. The enzyme activity of BaM6PI was optimal at pH and temperature of 7.5 and 70°C, respectively, with a kcat/Km of 13,900 s-1 mM-1 for mannose-6-phosphate (M6P). The purified BaM6PI demonstrated the highest catalytic efficiency of all characterized M6PIs. Although M6PIs have been characterized from several other sources, BaM6PI is distinguished from other M6PIs by its wide pH range and high catalytic efficiency for M6P. The binding orientation of the substrate M6P in the active site of BaM6PI shed light on the molecular basis of its unusually high activity. BaM6PI showed 97% substrate conversion from M6P to fructose-6-phosphate demonstrating the potential for using BaM6PI in industrial applications. PMID:26171785

  13. Cloning and characterization of genes encoding trehalose-6-phosphate synthase (TPS1) and trehalose-6-phosphate phosphatase (TPS2) from Zygosaccharomyces rouxii.

    PubMed

    Kwon, Hawk-Bin; Yeo, Eun-Taeg; Hahn, Sang-Eun; Bae, Shin-Chul; Kim, Dool-Yi; Byun, Myung-Ok

    2003-06-01

    In many organisms, trehalose protects against several environmental stresses, such as heat, desiccation, and salt, probably by stabilizing protein structures and lipid membranes. Trehalose synthesis in yeast is mediated by a complex of trehalose-6-phosphate synthase (TPS1) and trehalose-6-phosphate phosphatase (TPS2). In this study, genes encoding TPS1 and TPS2 were isolated from Zygosaccharomyces rouxii (designated ZrTPS1 and ZrTPS2, respectively). They were functionally identified by their complementation of the tps1 and tps2 yeast deletion mutants, which are unable to grow on glucose medium and with heat, respectively. Full-length ZrTPS1 cDNA is composed of 1476 nucleotides encoding a protein of 492 amino acids with a molecular mass of 56 kDa. ZrTPS2 cDNA consists of 2843 nucleotides with an open reading frame of 2700 bp, which encodes a polypeptide of 900 amino acids with a molecular mass of 104 kDa. The amino acid sequence encoded by ZrTPS1 has relatively high homology with TPS1 of Saccharomyces cerevisiae and Schizosaccharomyces pombe, compared with TPS2. Western blot analysis showed that the antibody against S. cerevisiae TPS1 recognizes ZrTPS1. Under normal growth conditions, ZrTPS1 and ZrTPS2 were highly and constitutively expressed, unlike S. cerevisiae TPS1 and TPS2. Salt stress and heat stress reduced the expression of the ZrTPS1 and ZrTPS2 genes, respectively.

  14. The erythrocyte calcium pump is inhibited by non-enzymic glycation: studies in situ and with the purified enzyme.

    PubMed Central

    González Flecha, F L; Castello, P R; Caride, A J; Gagliardino, J J; Rossi, J P

    1993-01-01

    In a previous paper we demonstrated that incubation of either intact erythrocytes or erythrocytes membranes with glucose decreases the activity of the membrane Ca(2+)-ATPase [González Flecha, Bermúdez, Cédola, Gagliardino and Rossi (1990) Diabetes 39, 707-711]. The aim of the present work was to obtain information about the mechanism of this inhibition. For this purpose, experiments were carried out with purified Ca(2+)-ATPase, inside-out vesicles and membranes from human erythrocytes. Incubation of the purified Ca(2+)-ATPase with glucose led to a decay in the enzyme activity of up to 50% of the control activity under the conditions used. The decrease in ATPase activity was concomitant with labelling by [6-3H]glucose of the purified Ca2+ pump; the kinetic properties of both processes were almost identical, suggesting that inhibition is a consequence of the incorporation of glucose into the Ca(2+)-ATPase molecule. In inside-out vesicles, glucose also promoted inhibition of Ca(2+)-ATPase activity as well as of active Ca2+ transport. Arabinose, xylose, mannose, ribose, fructose and glucose 6-phosphate (but not mannitol) were also able to inactive the ATPase. The activation energy for both the decrease in ATPase activity by glucose and the labelling of the pump with [6-3H]glucose was about 65 kJ/mol. Furthermore, inorganic phosphate enhanced the inactivation of the Ca(2+)-ATPase by glucose. This evidence strongly suggests that inhibition is a non-enzymically catalysed process. Inactivation of the Ca(2+)-ATPase by glucose was enhanced by reductive alkylation with sodium borohydride. Aminoguanidine, an inhibitor of the formation of the advanced end products of glycosylation, did not prevent the deleterious effect of glucose on the enzyme activity. Therefore it is concluded that inactivation of the Ca2+ pump is a consequence of the glycation of this protein. PMID:8393658

  15. Attenuation of erythrocyte membrane oxidative stress by Sesbania grandiflora in streptozotocin-induced diabetic rats.

    PubMed

    Sureka, Chandrabose; Ramesh, Thiyagarajan; Begum, Vavamohaideen Hazeena

    2015-08-01

    The aim of the present study was to investigate the protective effects of Sesbania grandiflora flower (SGF) extract on erythrocyte membrane in Streptozotocin (STZ)-induced diabetic rats. Adult male albino rats of Wistar strain, weighing 190-220 g, were made diabetic by an intraperitonial administration of STZ (45 mg/kg). Normal and diabetic rats were treated with SGF, and diabetic rats were also treated with glibenclamide as drug control, for 45 days. In this study plasma insulin and haemoglobin levels were decreased and blood glucose, glycosylated haemoglobin, protein oxidation, lipid peroxidation markers, and osmotic fragility levels were increased in diabetic rats. Moreover, erythrocytes antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxide, glutathione reductase, glutathione-S-transferase, and glucose-6-phosphate dehydrogenase activities and non-enzymatic antioxidants such as vitamin C, vitamin E, reduced glutathione (GSH), and oxidized glutathione (GSSG) levels were altered. Similarly, the activities of total ATPases, Na(+)/K(+)-ATPase, Ca(2+)-ATPase, and Mg(2+)-ATPase were also decreased in the erythrocytes of diabetic rats. Administration of SGF to STZ-induced diabetic rats reduced blood glucose and glycosylated haemoglobin levels with increased levels of insulin and haemoglobin. Moreover, SGF reversed the protein and lipid peroxidation markers, osmotic fragility, membrane-bound ATPases activities, and antioxidant status in STZ-induced diabetic rats. These results suggest that SGF could provide a protective effect on diabetes by decreasing oxidative stress-associated diabetic complications.

  16. Comparative study of erythrocyte glycolytic enzymes in man and in two species of Lagomorphae. (Ochotona rufescens rufescens and Oryctolagus cuniculus).

    PubMed

    Puget, A; Vergnes, H; Gouarderes, C

    1974-07-01

    The authors made a comparative study of red cell enzyme glycolysis in man and in two species of Lagomorphae, the pika and the rabbit. The activities of the 12 enzymes of Embden-Meyerhoff pathway and of the two dehydrogenases of pentose shunt (glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase) were determined. Phosphoglycerate kinase and pyruvate kinase showed quite similar activities in pika erythrocytes and in erythrocytes from human umbilical cord. The levels of these enzymes differed significantly in the pika and in the rabbit. No differences were noted between pyruvate kinases from the rabbit and the neonatal man. The other activities gave values either identical to those found in the adult man or intermediate between the adult and the neonatal man. In the rabbit the levels of glycolitic enzymes were generally lower than in the pika except for lactate dehydrogenase and glycose-6-phosphate dehydrogenase. Some characteristics of erythrocyte metabolism specific to the pika may account for the differences observed in this species. The influence of red cell age cannot explain the variations observed for no significant reticulocytosis was observed in the circulating blood. The percentages found in the pika and the rabbit were essentially identical at determination.

  17. Expansive evolution of the trehalose-6-phosphate phosphatase gene family in Arabidopsis.

    PubMed

    Vandesteene, Lies; López-Galvis, Lorena; Vanneste, Kevin; Feil, Regina; Maere, Steven; Lammens, Willem; Rolland, Filip; Lunn, John E; Avonce, Nelson; Beeckman, Tom; Van Dijck, Patrick

    2012-10-01

    Trehalose is a nonreducing sugar used as a reserve carbohydrate and stress protectant in a variety of organisms. While higher plants typically do not accumulate high levels of trehalose, they encode large families of putative trehalose biosynthesis genes. Trehalose biosynthesis in plants involves a two-step reaction in which trehalose-6-phosphate (T6P) is synthesized from UDP-glucose and glucose-6-phosphate (catalyzed by T6P synthase [TPS]), and subsequently dephosphorylated to produce the disaccharide trehalose (catalyzed by T6P phosphatase [TPP]). In Arabidopsis (Arabidopsis thaliana), 11 genes encode proteins with both TPS- and TPP-like domains but only one of these (AtTPS1) appears to be an active (TPS) enzyme. In addition, plants contain a large family of smaller proteins with a conserved TPP domain. Here, we present an in-depth analysis of the 10 TPP genes and gene products in Arabidopsis (TPPA-TPPJ). Collinearity analysis revealed that all of these genes originate from whole-genome duplication events. Heterologous expression in yeast (Saccharomyces cerevisiae) showed that all encode active TPP enzymes with an essential role for some conserved residues in the catalytic domain. These results suggest that the TPP genes function in the regulation of T6P levels, with T6P emerging as a novel key regulator of growth and development in higher plants. Extensive gene expression analyses using a complete set of promoter-β-glucuronidase/green fluorescent protein reporter lines further uncovered cell- and tissue-specific expression patterns, conferring spatiotemporal control of trehalose metabolism. Consistently, phenotypic characterization of knockdown and overexpression lines of a single TPP, AtTPPG, points to unique properties of individual TPPs in Arabidopsis, and underlines the intimate connection between trehalose metabolism and abscisic acid signaling.

  18. [Sorbitol-6-Phosphate Dehydrogenase Gene Polymorhism in Malus Mill. (Rosaceae)].

    PubMed

    Boris, K V; Kudryavtsev, A M; Kochieva, E Z

    2015-11-01

    The sorbitol-6-phosphate dehydrogenase gene (S6PDH) sequences of six representatives of the genus Malus, which belong to five different taxonomic sections, were examined for the first time. The exon-intron structure and polymorphism of the nucleotide and amino acid sequences of these genes was characterized. The intraspecific polymorphism of the S6PDH gene was assessed for the first time in 40 Russian and foreign apple (Malus domestica) cultivars. It was demonstrated that the interspecific polymorphism level of the S6PDH coding sequences in the studied. representatives of the genus Malus was 4%, and the intraspecific polymorphism level of M. domestica cultivars was very low, constituting 0.96%.

  19. Physical mapping of the human glutamine:fructose-6-phosphate amidotransferase gene (GFPT) to chromosome 2p13

    SciTech Connect

    Whitmore, T.E.; Mudri, S.L.; McKnight, G.L.

    1995-03-20

    Diabetic hyperglycemia influences insulin resistance through a process termed glucose toxicity. Implicated as a source of the mediators of this toxicity is an increased intracellular glucose metabolism through the hexosamine pathway. The hexosamine pathway itself is controlled by the rate-limiting enzyme glutamine:fructose-6-phosphate amidotransferase (GFAT), which is the first enzyme of the pathway. It has been shown that there is a close correlation between the glucose-mediated reduction of GFAT activity and the onset of insulin desensitization of the glucose transport system, a condition associated with insulin-resistant states of non-insulin-dependent diabetes mellitus and obesity. To gain a better understanding of the molecular regulation of GFAT and its role in the induction of insulin resistance, we previously isolated and cloned the cDNA for the human form of this enzyme and expressed the functional protein in Escherichia coli. 9 refs., 1 fig.

  20. Regulation of membrane-cytoskeletal interactions by tyrosine phosphorylation of erythrocyte band 3

    PubMed Central

    Ferru, Emanuela; Giger, Katie; Pantaleo, Antonella; Campanella, Estela; Grey, Jesse; Ritchie, Ken; Vono, Rosa; Low, Philip S.

    2011-01-01

    The cytoplasmic domain of band 3 serves as a center of erythrocyte membrane organization and constitutes the major substrate of erythrocyte tyrosine kinases. Tyrosine phosphorylation of band 3 is induced by several physiologic stimuli, including malaria parasite invasion, cell shrinkage, normal cell aging, and oxidant stress (thalassemias, sickle cell disease, glucose-6-phosphate dehydrogenase deficiency, etc). In an effort to characterize the biologic sequelae of band 3 tyrosine phosphorylation, we looked for changes in the polypeptide's function that accompany its phosphorylation. We report that tyrosine phosphorylation promotes dissociation of band 3 from the spectrin-actin skeleton as evidenced by: (1) a decrease in ankyrin affinity in direct binding studies, (2) an increase in detergent extractability of band 3 from ghosts, (3) a rise in band 3 cross-linkability by bis-sulfosuccinimidyl-suberate, (4) significant changes in erythrocyte morphology, and (5) elevation of the rate of band 3 diffusion in intact cells. Because release of band 3 from its ankyrin and adducin linkages to the cytoskeleton can facilitate changes in multiple membrane properties, tyrosine phosphorylation of band 3 is argued to enable adaptive changes in erythrocyte biology that permit the cell to respond to the above stresses. PMID:21474668

  1. Host erythrocyte polymorphisms and exposure to Plasmodium falciparum in Papua New Guinea

    PubMed Central

    Fowkes, Freya JI; Michon, Pascal; Pilling, Lynn; Ripley, Ruth M; Tavul, Livingstone; Imrie, Heather J; Woods, Caira M; Mgone, Charles S; Luty, Adrian JF; Day, Karen P

    2008-01-01

    Background The protection afforded by human erythrocyte polymorphisms against the malaria parasite, Plasmodium falciparum, has been proposed to be due to reduced ability of the parasite to invade or develop in erythrocytes. If this were the case, variable levels of parasitaemia and rates of seroconversion to infected-erythrocyte variant surface antigens (VSA) should be seen in different host genotypes. Methods To test this hypothesis, P. falciparum parasitaemia and anti-VSA antibody levels were measured in a cohort of 555 asymptomatic children from an area of intense malaria transmission in Papua New Guinea. Linear mixed models were used to investigate the effect of α+-thalassaemia, complement receptor-1 and south-east Asian ovalocytosis, as well as glucose-6-phosphate dehydrogenase deficiency and ABO blood group on parasitaemia and age-specific seroconversion to VSA. Results No host polymorphism showed a significant association with both parasite prevalence/density and age-specific seroconversion to VSA. Conclusion Host erythrocyte polymorphisms commonly found in Papua New Guinea do not effect exposure to blood stage P. falciparum infection. This contrasts with data for sickle cell trait and highlights that the above-mentioned polymorphisms may confer protection against malaria via distinct mechanisms. PMID:18173836

  2. Erythrocyte rheology.

    PubMed

    Stuart, J

    1985-09-01

    Erythrocyte deformability was formerly measured by its contribution to whole blood viscosity. It is now more commonly measured by filtration of erythrocytes through, or aspiration into, pores of 3-5 microns diameter and by the measurement of shear induced erythrocyte elongation using laser diffractometry. Recent improvements in the technology for erythrocyte filtration have included the removal of acute phase reactants from test erythrocyte suspensions, ultrasonic cleaning and reuse of filter membranes, awareness of the importance of mean cell volume as a determinant of flow through 3 microns diameter pores, and the ability to detect subpopulations of less deformable erythrocytes. Measurements of erythrocyte elongation by laser diffractometry, using the Ektacytometer, are also influenced by cell size and need to be corrected for mean cell volume. These advances have greatly improved the sensitivity and specificity of rheological methods for measuring the deformability of erythrocytes and for investigating the mode of action of rheologically active drugs.

  3. Structural and Chemical Basis for Glucosamine 6-Phosphate Binding and Activation of the glmS Ribozyme

    SciTech Connect

    Cochrane, J.; Lipchock, S; Smith, K; Strobel, S

    2009-01-01

    The glmS ribozyme is the first naturally occurring catalytic RNA that relies on an exogenous, nonnucleotide cofactor for reactivity. From a biochemical perspective, the glmS ribozyme derived from Bacillus anthracis is the best characterized. However, much of the structural work to date has been done on a variant glmS ribozyme, derived from Thermoanaerobacter tengcongensis. Here we present structures of the B. anthracis glmS ribozyme in states before the activating sugar, glucosamine 6-phosphate (GlcN6P), has bound and after the reaction has occurred. These structures show an active site preorganized to bind GlcN6P that retains some affinity for the sugar even after cleavage of the RNA backbone. A structure of an inactive glmS ribozyme with a mutation distal from the ligand-binding pocket highlights a nucleotide critical to the reaction that does not affect GlcN6P binding. Structures of the glmS ribozyme bound to a naturally occurring inhibitor, glucose 6-phosphate (Glc6P), and a nonnatural activating sugar, mannosamine 6-phosphate (MaN6P), reveal a binding mode similar to that of GlcN6P. Kinetic analyses show a pH dependence of ligand binding that is consistent with titration of the cofactor's phosphate group and support a model in which the major determinant of activity is the sugar amine independent of its stereochemical presentation.

  4. Trehalose 6-phosphate signal is closely related to sorbitol in apple (Malus domestica Borkh. cv. Gala)

    PubMed Central

    Zhang, Wen; Lunn, John E.; Feil, Regina; Wang, Yufei; Zhao, Jingjing; Tao, Hongxia; Zhao, Zhengyang

    2017-01-01

    ABSTRACT Trehalose-6-phosphate (Tre6P) is a precursor of trehalose, which is widespread in nature and greatly influences plant growth and development. Tre6P acts as a signal of carbon availability in many plants, but little is known about the function of Tre6P in rosaceous plants, which have specific sorbitol biosynthesis and transportation pathways. In the present study, Tre6P levels and Sorbitol:Tre6P ratios were analyzed in apple (Malus domestica, Borkh. cv. Gala). Tre6P levels were positively correlated with sorbitol content but negatively correlated with sucrose, glucose, and fructose content in developing fruit. However, under sorbitol-limited conditions, Tre6P levels were positively correlated with both sorbitol and sucrose. In the presence of different exogenous sugar supply, Tre6P levels increased corresponding with sorbitol, but this was not the case with sucrose. In addition, Tre6P content and sorbitol:Tre6P ratios were more highly correlated with ADP-glucose levels under sorbitol-limited conditions and fruit development stages, respectively. These results suggest that Tre6P is more closely related to sorbitol than other soluble sugars and has an important role in influencing carbon metabolism in apple. PMID:28069587

  5. Metabolic phenotypes of Saccharomyces cerevisiae mutants with altered trehalose 6-phosphate dynamics.

    PubMed

    Walther, Thomas; Mtimet, Narjes; Alkim, Ceren; Vax, Amélie; Loret, Marie-Odile; Ullah, Azmat; Gancedo, Carlos; Smits, Gertien J; François, Jean Marie

    2013-09-01

    In Saccharomyces cerevisiae, synthesis of T6P (trehalose 6-phosphate) is essential for growth on most fermentable carbon sources. In the present study, the metabolic response to glucose was analysed in mutants with different capacities to accumulate T6P. A mutant carrying a deletion in the T6P synthase encoding gene, TPS1, which had no measurable T6P, exhibited impaired ethanol production, showed diminished plasma membrane H⁺-ATPase activation, and became rapidly depleted of nearly all adenine nucleotides which were irreversibly converted into inosine. Deletion of the AMP deaminase encoding gene, AMD1, in the tps1 strain prevented inosine formation, but did not rescue energy balance or growth on glucose. Neither the 90%-reduced T6P content observed in a tps1 mutant expressing the Tps1 protein from Yarrowia lipolytica, nor the hyperaccumulation of T6P in the tps2 mutant had significant effects on fermentation rates, growth on fermentable carbon sources or plasma membrane H⁺-ATPase activation. However, intracellular metabolite dynamics and pH homoeostasis were strongly affected by changes in T6P concentrations. Hyperaccumulation of T6P in the tps2 mutant caused an increase in cytosolic pH and strongly reduced growth rates on non-fermentable carbon sources, emphasizing the crucial role of the trehalose pathway in the regulation of respiratory and fermentative metabolism.

  6. Glucosamine and Glucosamine-6-phosphate Derivatives: Catalytic Cofactor Analogs for the glmS Ribozyme

    PubMed Central

    Posakony, Jeffrey J.; Ferré-D'Amaré, Adrian R.

    2013-01-01

    Two analogues of glucosamine-6-phosphate (GlcN6P, 1) and five of glucosamine (GlcN, 2) were prepared for evaluation as catalytic cofactor of the glmS ribozyme, a bacterial gene-regulatory RNA that controls cell wall biosynthesis. Glucosamine and allosamine with 3-azido substitutions were prepared by SN2 reactions of the respective 1,2,4,6-protected sugars; final acidic hydrolysis afforded the fully deprotected compounds as their TFA salts. A 6-phospho-2-aminoglucolactam (31) was prepared from glucosamine in a 13-step synthesis, which included a late-stage POCl3-phosphorylation. A simple and widely applicable 2-step procedure with the triethylsilyl (TES) protecting group was developed to selectively expose the 6-OH group in N-protected glucosamine analogs, which provided another route to chemical phosphorylation. Mitsunobu chemistry afforded 6-cyano (35) and 6-azido (36) analogues of GlcN-(Cbz) and the selectivity for the 6-position was confirmed by NMR (COSY, HMBC, HMQC) experiments. Compound 36 was converted to the fully deprotected 6-azido-GlcN (37) and 2,6-diaminoglucose (38) analogs. A 2-hydroxylamino glucose (42) analogue was prepared via an oxaziridine (41). Enzymatic phosphorylation of 42 and chemical phosphorylation of its 6-OH precursor (43) were possible, but 42 and the 6-phospho product (44) were unstable under neutral or basic conditions. Chemical phosphorylation of the previously described 2-guanidinyl-glucose (46) afforded its 6-phospho analogue (49) after final deprotection. PMID:23578404

  7. Trehalose 6-phosphate signal is closely related to sorbitol in apple (Malus domestica Borkh. cv. Gala).

    PubMed

    Zhang, Wen; Lunn, John E; Feil, Regina; Wang, Yufei; Zhao, Jingjing; Tao, Hongxia; Guo, Yanping; Zhao, Zhengyang

    2017-02-15

    Trehalose-6-phosphate (Tre6P) is a precursor of trehalose, which is widespread in nature and greatly influences plant growth and development. Tre6P acts as a signal of carbon availability in many plants, but little is known about the function of Tre6P in rosaceous plants, which have specific sorbitol biosynthesis and transportation pathways. In the present study, Tre6P levels and Sorbitol:Tre6P ratios were analyzed in apple (Malus domestica, Borkh. cv. Gala). Tre6P levels were positively correlated with sorbitol content but negatively correlated with sucrose, glucose, and fructose content in developing fruit. However, under sorbitol-limited conditions, Tre6P levels were positively correlated with both sorbitol and sucrose. In the presence of different exogenous sugar supply, Tre6P levels increased corresponding with sorbitol, but this was not the case with sucrose. In addition, Tre6P content and sorbitol:Tre6P ratios were more highly correlated with ADP-glucose levels under sorbitol-limited conditions and fruit development stages, respectively. These results suggest that Tre6P is more closely related to sorbitol than other soluble sugars and has an important role in influencing carbon metabolism in apple.

  8. {open_quotes}The effects of diabetes on the activity of the enzyme glutamine: fructose-6-phosphate amindotransferase{close_quotes}

    SciTech Connect

    Nelson, S.P.

    1994-12-31

    Hexsoamine synthetic pathway (HexNSP) controls the supply of essential substrates for glycoprotein synthesis. In vitro studies suggest that increased flux of glucose via the hexsoamine synthetic pathway may play a role in glucose induced insulin resistance of glucose transport. Glutamine: fructose-6-phosphate amindotransferase (GFAT) controls flux into the hexsoamine synthetic pathway; the major products are UDPN-acetylhexosamines (UDP.HexNac=UDP.GlcNAc= UDP.GalNac). I examined whether diabetes ({approximately} 7 days post intravenous streptozotocin, and genetically linked) affects the activity of glutamine: fructose-6-phosphate in rat and mouse skeletal muscle in vivo. Nucleotide linked HexNAc were analyzed by high pressure liquid chromatography(HPLC) in deproteinized hind limb muscle extracts.

  9. Some Properties of Potato Tuber UDPGd-fructose-2-glucosyltransferase (E.C. 2.4.1.14) and UDPGd-fructose-6-phosphate-2-glucosyltransferase (E.C. 2.4.1.13) 1

    PubMed Central

    Slabnik, Estanislava; Frydman, Rosalia B.; Cardini, Carlos E.

    1968-01-01

    Sucrose and sucrose 6-phosphate synthetase were isolated from potato tubers, partially purified and their properties studied. The sucrose synthetase showed optimum activity at 45° and was inhibited competitively by ADP and some phenolic glucosides. The Ki′s for these inhibitors were determined. Mg2+ was found to activate this enzyme. Activity toward UDP-glucose or ADP-glucose formation was measured. The optimum conditions for sucrose and UDP-glucose formation were found to differ. The specificity for the glucosyl donor and acceptor were determined. The optimum conditions for sucrose 6-phosphate synthetase activity were studied. This enzyme was not inhibited by either ADP or phenolic glucosides; UDP-glucose was the only glucosyl donor for sucrose 6-phosphate formation. PMID:16656883

  10. Human erythrocyte hemolysis induced by selenium and tellurium compounds increased by GSH or glucose: a possible involvement of reactive oxygen species.

    PubMed

    Schiar, Viviane Patrícia P; Dos Santos, Danúbia B; Paixão, Márcio W; Nogueira, Cristina Wayne; Rocha, João Batista T; Zeni, Gilson

    2009-01-15

    Oxidative stress can induce complex alterations of membrane proteins in red blood cells (RBCs) eventually leading to hemolysis. RBCs represent a good model to investigate the damage induced by oxidizing agents. Literature data have reported that chalcogen compounds can present pro-oxidant properties with potent inhibitory effects on cell growth, causing tissue damage and inhibit a variety of enzymes. In this study, human erythrocytes were incubated in vitro with various chalcogen compounds at 37 degrees C: diphenyl ditelluride (1), dinaphthalen diteluride (2), diphenyl diselenide (3), (S)-tert-butyl 1-diselenide-3-methylbutan-2-ylcarbamate (4), (S)-tert-butyl 1-diselenide-3-phenylpropan-2-ylcarbamate (5), selenium dioxide (6) and sodium selenite (7) in order to investigate their potential in vitro toxicity. After 6h of incubation, all the tested compounds increased the hemolysis rate, when compared to control and compound (2) had the most potent hemolytic effect. The addition of reduced glutathione (GSH) or glucose to the incubation medium enhanced hemolysis caused by chalcogen compounds. The thiol oxidase activity of these compounds was evaluated by measuring the rate of cysteine (CYS) and dithiotreitol (DTT) oxidation. DTT and cysteine oxidation was increased by all the compounds tested. The results suggest a relationship between the oxidation of intracellular GSH and subsequent generation of free radicals with the hemolysis by chalcogen compounds.

  11. Liver glucose metabolism in humans

    PubMed Central

    Adeva-Andany, María M.; Pérez-Felpete, Noemi; Fernández-Fernández, Carlos; Donapetry-García, Cristóbal; Pazos-García, Cristina

    2016-01-01

    Information about normal hepatic glucose metabolism may help to understand pathogenic mechanisms underlying obesity and diabetes mellitus. In addition, liver glucose metabolism is involved in glycosylation reactions and connected with fatty acid metabolism. The liver receives dietary carbohydrates directly from the intestine via the portal vein. Glucokinase phosphorylates glucose to glucose 6-phosphate inside the hepatocyte, ensuring that an adequate flow of glucose enters the cell to be metabolized. Glucose 6-phosphate may proceed to several metabolic pathways. During the post-prandial period, most glucose 6-phosphate is used to synthesize glycogen via the formation of glucose 1-phosphate and UDP–glucose. Minor amounts of UDP–glucose are used to form UDP–glucuronate and UDP–galactose, which are donors of monosaccharide units used in glycosylation. A second pathway of glucose 6-phosphate metabolism is the formation of fructose 6-phosphate, which may either start the hexosamine pathway to produce UDP-N-acetylglucosamine or follow the glycolytic pathway to generate pyruvate and then acetyl-CoA. Acetyl-CoA may enter the tricarboxylic acid (TCA) cycle to be oxidized or may be exported to the cytosol to synthesize fatty acids, when excess glucose is present within the hepatocyte. Finally, glucose 6-phosphate may produce NADPH and ribose 5-phosphate through the pentose phosphate pathway. Glucose metabolism supplies intermediates for glycosylation, a post-translational modification of proteins and lipids that modulates their activity. Congenital deficiency of phosphoglucomutase (PGM)-1 and PGM-3 is associated with impaired glycosylation. In addition to metabolize carbohydrates, the liver produces glucose to be used by other tissues, from glycogen breakdown or from de novo synthesis using primarily lactate and alanine (gluconeogenesis). PMID:27707936

  12. Cytochrome P{sub 450}-dependent toxic effects of primaquine on human erythrocytes

    SciTech Connect

    Ganesan, Shobana; Tekwani, Babu L.; Sahu, Rajnish; Tripathi, Lalit M.; Walker, Larry A.

    2009-11-15

    Primaquine, an 8-aminoquinoline, is the drug of choice for radical cure of relapsing malaria. Use of primaquine is limited due to its hemotoxicity, particularly in populations with glucose-6-phosphate dehydrogenase deficiency [G6PD(-)]. Biotransformation appears to be central to the anti-infective and hematological toxicities of primaquine, but the mechanisms are still not well understood. Metabolic studies with primaquine have been hampered due to the reactive nature of potential hemotoxic metabolites. An in vitro metabolism-linked hemotoxicity assay has been developed. Co-incubation of the drug with normal or G6PD(-) erythrocytes, microsomes or recombinant cytochrome P{sub 450} (CYP) isoforms has allowed in situ generation of potential hemotoxic metabolite(s), which interact with the erythrocytes to generate hemotoxicity. Methemoglobin formation, real-time generation of reactive oxygen intermediates (ROIs) and depletion of reactive thiols were monitored as multiple biochemical end points for hemotoxicity. Primaquine alone did not produce any hemotoxicity, while a robust increase was observed in methemoglobin formation and generation of ROIs by primaquine in the presence of human or mouse liver microsomes. Multiple CYP isoforms (CYP2E1, CYP2B6, CYP1A2, CYP2D6 and CYP3A4) variably contributed to the hemotoxicity of primaquine. This was further confirmed by significant inhibition of primaquine hemotoxicity by the selective CYP inhibitors, namely thiotepa (CYP2B6), fluoxetine (CYP2D6) and troleandomycin (CYP3A4). Primaquine caused similar methemoglobin formation in G6PD(-) and normal human erythrocytes. However, G6PD(-) erythrocytes suffered higher oxidative stress and depletion of thiols than normal erythrocytes due to primaquine toxicity. The results provide significant insights regarding CYP isoforms contributing to hemotoxicity and may be useful in controlling toxicity of primaquine to increase its therapeutic utility.

  13. A role for AMPK in the inhibition of glucose-6-phosphate dehydrogenase by polyunsaturated fatty acids

    SciTech Connect

    Kohan, Alison B.; Talukdar, Indrani; Walsh, Callee M.; Salati, Lisa M.

    2009-10-09

    Both polyunsaturated fatty acids and AMPK promote energy partitioning away from energy consuming processes, such as fatty acid synthesis, towards energy generating processes, such as {beta}-oxidation. In this report, we demonstrate that arachidonic acid activates AMPK in primary rat hepatocytes, and that this effect is p38 MAPK-dependent. Activation of AMPK mimics the inhibition by arachidonic acid of the insulin-mediated induction of G6PD. Similar to intracellular signaling by arachidonic acid, AMPK decreases insulin signal transduction, increasing Ser{sup 307} phosphorylation of IRS-1 and a subsequent decrease in AKT phosphorylation. Overexpression of dominant-negative AMPK abolishes the effect of arachidonic acid on G6PD expression. These data suggest a role for AMPK in the inhibition of G6PD by polyunsaturated fatty acids.

  14. Identification of glucose-6-phosphate transporter as a key regulator functioning at the autophagy initiation step.

    PubMed

    Ahn, Hye-Hyun; Oh, Yumin; Lee, Huikyong; Lee, WonJae; Chang, Jae-Woong; Pyo, Ha-Kyung; Nah, Do hyung; Jung, Yong-Keun

    2015-07-22

    Autophagy is a catabolic process involving autophagosome formation via lysosome. However, the initiation step of autophagy is largely unknown. We found an interaction between ULK1 and ATG9 in mammalian cells and utilized the interaction to identify novel regulators of autophagy upstream of ULK1. We established a cell-based screening assay employing bimolecular fluorescence complementation. By performing gain-of-function screening, we identified G6PT as an autophagy activator. G6PT enhanced the interaction between N-terminal Venus-tagged ULK1 and C-terminal Venus-tagged ATG9, and increased autophagic flux independent of its transport activity. G6PT negatively regulated mTORC1 activity, demonstrating that G6PT functions upstream of mTORC1 in stimulating autophagy.

  15. A ROLE FOR AMPK IN THE INHIBITION OF GLUCOSE-6-PHOSPHATE DEHYDROGENASE BY POLYUNSATURATED FATTY ACIDS

    PubMed Central

    Kohan, Alison B.; Talukdar, Indrani; Walsh, Callee M.; Salati, Lisa M.

    2009-01-01

    Both polyunsaturated fatty acids and AMPK promote energy partitioning away from energy consuming processes, such as fatty acid synthesis, towards energy generating processes, such as β-oxidation. In this report, we demonstrate that arachidonic acid activates AMPK in primary rat hepatocytes, and that this effect is p38 MAPK-dependent. Activation of AMPK mimics the inhibition by arachidonic acid of the insulin-mediated induction of G6PD. Similar to intracellular signaling by arachidonic acid, AMPK decreases insulin signal transduction, increasing Ser307 phosphorylation of IRS-1 and a subsequent decrease in AKT phosphorylation. Overexpression of dominant-negative AMPK abolishes the effect of arachidonic acid on G6PD expression. These data suggest a role for AMPK in the inhibition of G6PD by polyunsaturated fatty acids. PMID:19646964

  16. IMMUNOGLOBULIN AND GLUCOSE-6-PHOSPHATE DEHYDROGENASE AS MARKERS OF CELLULAR ORIGIN IN BURKITT LYMPHOMA

    PubMed Central

    Fialkow, Philip J.; Klein, Eva; Klein, George; Clifford, Peter; Singh, Surjit

    1973-01-01

    Two independent marker systems, G-6-PD isoenzymes and cell membrane-associated IgM, were used to trace the cellular origin of Burkitt lymphoma. Application of the G-6-PD system is dependent upon the fact that, in accordance with inactivity of one X chromosome in each somatic cell, females heterozygous for the usual B gene (GdB) at the X-linked G-6-PD locus and the variant allele GdA (or GdA-) have two types of cells. GdB is active in one cell population, which consequently produces B type enzyme; in the other population GdA is active, producing the variant A enzyme. Therefore, tumors with a clonal origin in a GdB/GdA heterozygote should exhibit only one enzyme type (B or A) whereas those with multicellular origin may show both A and B enzymes. Utilization of the immunoglobulin system is based upon the supposition that in lymphoid neoplasms with clonal origin either all or none of the tumor cells should have surface-associated IgM and κ-reactivities. 33 of 34 relatively homogeneous (with respect to content of neoplastic cells) individual Burkitt tumors from 19 G-6-PD heterozygotes had single enzyme phenotypes. Similarly, of 95 tumors tested, 92 consisted essentially of IgM(+) or (-) cells. Two neoplasms could not be definitely classified and one tumor had two cell populations. These data suggest a clonal origin for most Burkitt tumors, but the one neoplasm with a double G-6-PD phenotype (A/B) and the one tumor that had two populations of cells with respect to surface IgM, could have originated from multiple cells. G-6-PD was determined in each of two tumors from seven heterozygotes and in all cases both tumors had the same single enzyme phenotype. Surface-associated IgM was tested in four tumors from one patient, three from another, and in two neoplasms from 11 patients. With one exception, all tumors from the same patient were concordant with respect to IgM. These findings suggest that the entire disease has a clonal origin, i.e., it emerges at one focus and then spreads to other parts of the body. Cells from 36 recurrent neoplasms were typed for G-6-PD (in heterozygotes) and/or IgM. In one previously reported patient, initial and recurrent tumors were discordant for G-6-PD. Two other patients had IgM phenotypes in recurrences that were discordant with those found in their initial tumors. Phenotypes from three of nine relapses which occurred after 5 mo were discordant for G-6-PD or IgM but no discordance was detected among 27 earlier recurrences. Thus, some "late" recurrences may be due to emergence of "new" maligant cell lines whereas most early relapses are due to reemergence of the original malignant clones. The probable unicellular origin of Burkitt lymphoma and the findings in tumor recurrences are discussed in terms of the disease's putative viral etiology. PMID:4577623

  17. Chloroamphenicol-Induced Hemolysis in Caucasian Glucose-6-Phosphate Dehydrogenase Deficiency

    DTIC Science & Technology

    typhoid fever with chloramphenicol. Two of these patients were studied when free of infection to determine the hemolytic potential of chloramphenicol in the noninfected G6PD-deficient white person. It was found to be mildly hemolytic under these conditions, suggesting that a drug- disease synergism was primarily responsible for the clinical hemolytic reactions. The febrile state itself, or changes in plasma amino acids accompanying infection, may be responsible for disease-related

  18. The glucose 6-phosphate shunt around the Calvin-Benson cycle.

    PubMed

    Sharkey, Thomas D; Weise, Sean E

    2016-07-01

    It is just over 60 years since a cycle for the regeneration of the CO2-acceptor used in photosynthesis was proposed. In this opinion paper, we revisit the origins of the Calvin-Benson cycle that occurred at the time that the hexose monophosphate shunt, now called the pentose phosphate pathway, was being worked out. Eventually the pentose phosphate pathway was separated into two branches, an oxidative branch and a non-oxidative branch. It is generally thought that the Calvin-Benson cycle is the reverse of the non-oxidative branch of the pentose phosphate pathway but we describe crucial differences and also propose that some carbon routinely passes through the oxidative branch of the pentose phosphate pathway. This creates a futile cycle but may help to stabilize photosynthesis. If it occurs it could explain a number of enigmas including the lack of complete labelling of the Calvin-Benson cycle intermediates when carbon isotopes are fed to photosynthesizing leaves. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  19. Energy balance-dependent regulation of ovine glucose 6-phosphate dehydrogenase protein isoform expression

    PubMed Central

    Triantaphyllopoulos, Kostas A; Laliotis, George P; Bizelis, Iosif A

    2014-01-01

    G6PDH is the rate-limiting enzyme of the pentose phosphate pathway and one of the principal source of NADPH, a major cellular reductant. Importantly, in ruminant's metabolism the aforementioned NADPH provided, is utilized for de novo fatty acid synthesis. Previous work of cloning the ovine (Ovis aries) og6pdh gene has revealed the presence of two cDNA transcripts (og6pda and og6pdb), og6pdb being a product of alternative splicing not similar to any other previously reported.1 In the current study the effect of energy balance in the ovine G6PDH protein expression was investigated, shedding light on the biochemical features and potential physiological role of the oG6PDB isoform. Changes in energy balance leads to protein expression changes in both transcripts, to the opposite direction and not in a proportional way. Negative energy balance was not in favor of the presence of any particular isoform, while both protein expression levels were not significantly different (P > 0.05). In contrast, at the transition point from negative to positive and on the positive energy balance, there is a significant increase of oG6PDA compared with oG6PDB protein expression (P < 0.001). Both oG6PDH protein isoforms changed significantly toward the positive energy balance. oG6PDA is escalating, while oG6PDB is falling, under the same stimulus (positive energy balance alteration). This change is also positively associated with increasing levels in enzyme activity, 4 weeks post-weaning in ewes’ adipose tissue. Furthermore, regression analysis clearly demonstrated the linear correlation of both proteins in response to the WPW, while energy balance, enzyme activity, and oG6PDA relative protein expression follow the same escalating trend; in contrast, oG6PDB relative protein expression falls in time, similar to both transcripts accumulation pattern, as reported previously.2 PMID:24575366

  20. Energy balance-dependent regulation of ovine glucose 6-phosphate dehydrogenase protein isoform expression.

    PubMed

    Triantaphyllopoulos, Kostas A; Laliotis, George P; Bizelis, Iosif A

    2014-01-01

    G6PDH is the rate-limiting enzyme of the pentose phosphate pathway and one of the principal source of NADPH, a major cellular reductant. Importantly, in ruminant's metabolism the aforementioned NADPH provided, is utilized for de novo fatty acid synthesis. Previous work of cloning the ovine (Ovis aries) og6pdh gene has revealed the presence of two cDNA transcripts (og6pda and og6pdb), og6pdb being a product of alternative splicing not similar to any other previously reported.(1) In the current study the effect of energy balance in the ovine G6PDH protein expression was investigated, shedding light on the biochemical features and potential physiological role of the oG6PDB isoform. Changes in energy balance leads to protein expression changes in both transcripts, to the opposite direction and not in a proportional way. Negative energy balance was not in favor of the presence of any particular isoform, while both protein expression levels were not significantly different (P > 0.05). In contrast, at the transition point from negative to positive and on the positive energy balance, there is a significant increase of oG6PDA compared with oG6PDB protein expression (P < 0.001). Both oG6PDH protein isoforms changed significantly toward the positive energy balance. oG6PDA is escalating, while oG6PDB is falling, under the same stimulus (positive energy balance alteration). This change is also positively associated with increasing levels in enzyme activity, 4 weeks post-weaning in ewes' adipose tissue. Furthermore, regression analysis clearly demonstrated the linear correlation of both proteins in response to the WPW, while energy balance, enzyme activity, and oG6PDA relative protein expression follow the same escalating trend; in contrast, oG6PDB relative protein expression falls in time, similar to both transcripts accumulation pattern, as reported previously.(2.)

  1. [Molecular identification of glucose-6-phosphate dehydrogenase (G6PD) detected in neonatal screening].

    PubMed

    Zamorano-Jiménez, Clara Aurora; Baptista-González, Héctor Alfredo; Bouchán-Valencia, Patricia; Granados-Cepeda, Martha Lucía; Trueba-Gómez, Rocío; Coeto-Barona, Georgina; Rosenfeld-Mann, Fany; Rosa-Mireles, Luisa Blanca; Meléndez-Ramírez, Rocío

    2015-01-01

    To present the strategy of identifying the molecular variants of G6PD detected in neonatal screening (NS). We present a series of incident cases of newborns positive for G6PD deficiency detected in NS. From nuclear DNA with the methodology of real-time PCR we sought molecular G6PD variants: G202A, A376G, T968C and C563T. Of a total of 21,619 neonates, 41 cases were reactive in NS for G6PD (189.6/100,000 RN screened rate), 34 cases confirmed the molecular variant of G6PD (157.3/100,000 RN screened rate). The most frequent allele combination G202A/A376G (G6PD ratio and median activity, 0.460 and 1.72 ± 0.35 U/g Hb, respectively), followed by G202A (0.170 and 1.74 ± 0.27 U/g Hb) and A376G/T968C (ratio 0.150 and 1.10 ± 0.44 U/g Hb). The T968C allelic variant showed lower enzyme activity than the rest (1.1 ± 0.4; p = 0.02). Two women were detected with G6PD deficiency with G202A/A376G and G202A variant. African alleles were prevalently detected in neonatal screening. This strategy allows the identification of molecular variants involved in 80% of cases.

  2. Relationship between exposure to icterogenic agents, glucose-6-phosphate dehydrogenase deficiency and neonatal jaundice in Nigeria.

    PubMed

    Owa, J A

    1989-11-01

    In a study of the relationship between exposure to icterogenic agents, G-6-PD deficiency and severe neonatal jaundice (NNJ) (serum bilirubin greater than or equal to 205 mumol/l) in 234 Nigerian term male neonates, 106 infants with severe NNJ and 128 controls, it was found that 62.3% of the jaundiced infants and 13.3% of the infants without NNJ were G6PD deficient (p less than 0.01). The proportion of infants exposed to icterogenic agents in the two groups was very similar (p greater than or equal to 0.5). There was a strong association between exposure to icterogenic agents and NNJ in 83 G6PD deficient infants (p less than 0.01), but there was no association between exposure to icterogenic agents and NNJ in the whole group of 234 infants or in 151 infants with normal G6PD status. It is concluded that there is an association between genetically determined G-6-PD deficiency and exogenous agents in causing severe NNJ in Nigerian infants.

  3. The risk of jaundice in glucose-6-phosphate dehydrogenase deficient babies exposed to menthol.

    PubMed

    Olowe, S A; Ransome-Kuti, O

    1980-05-01

    A major cause of neonatal morbidity and mortality in Lagos, Nigeria, is severe neonatal jaundice seen in G-6-PD deficient babies. The observation that the jaundice is more severe in outpatient than in inpatient babies suggests that its cause is exogenous. "Mentholated" powder which is commonly used in many clinics and at home to dress umbilical cords was suspected to be the offending agent. A controlled study of the effects of one of these powders was carried out on 60 consecutive G-6-PD deficient babies. In 30 of them the umbilical cords were dressed daily with the powder while the remaining half who were untreated served as controls. The treated babies developed statistically more significant jaundice than the controls. Inability of neonates to conjugate menthol in this power is probably responsible for the jaundice developed by these G-6-PD deficient babies. It is concluded that the use of menthol and/or camphor-containing commerical products on neonates be discontinued, especially in communities where the incidence of G-6-PD deficiency is high as the use of such products may be contributiing to the severity of neonatal jaundice.

  4. Lactose metabolism by Streptococcus mutans: evidence for induction of the tagatose 6-phosphate pathway.

    PubMed Central

    Hamilton, I R; Lebtag, H

    1979-01-01

    Growth on lactose by strains of Streptococcus mutans resulted in the induction of the lactose-phosphoenolpyruvate-phosphotransferase system, phospho-beta-galactosidase, and the enzymes of the tagatose 6-phosphate pathway. PMID:230175

  5. Glycosidases Interact Selectively With Mannose-6-Phosphate Receptors of Bull Spermatozoa.

    PubMed

    Aguilera, Andrea C; Boschin, Verónica; Carvelli, Lorena; Cavicchia, Juan C; Sosa, Miguel A

    2016-11-01

    Glycosidases may play a role in sperm maturation during epididymal transit. In this work, we describe the interaction of these enzymes with bull spermatozoa. We found that β-galactosidase associated to spermatozoa can be released under low ionic strength conditions, whereas the interaction of N-acetyl-β-D-glucosaminidase and β-glucuronidase with spermatozoa appeared to be stronger. On the other hand, α-mannosidase and α-fucosidase cannot be removed from the gametes. In addition, part of N-acetyl-β-D-glucosaminidase, β-galactosidase, and β-glucuronidase can also be released by mannose-6-phosphate. Taking into account these data, we explored the presence of cation-independent- and cation-dependent-mannose-6-phosphate receptors in the spermatozoa and found that cation-independent mannose-6-phosphate receptor is highly expressed in bull spermatozoa and cation-dependent-mannose-6-phosphate receptor is expressed at a lesser extent. In addition, by immunofluorescence, we observed that cation-independent-mannose-6-phosphate receptor is mostly located at the acrosomal zone, whereas cation-dependent-mannose-6-phosphate receptor presents a different distribution pattern on spermatozoa during the epididymal transit. N-acetyl-β-D-glucosaminidase and β-glucuronidase isolated from epididymal fluid interacted mostly with cation-independent-mannose-6-phosphate receptor, while β-galactosidase was recognized by both receptors. We concluded that glycosidases might play different roles in bull spermatozoa and that mannos-6-phosphate receptors may act as recruiters of some enzymes. J. Cell. Biochem. 117: 2464-2472, 2016. © 2016 Wiley Periodicals, Inc.

  6. Biochemical characterization of rice trehalose-6-phosphate phosphatases supports distinctive functions of these plant enzymes.

    PubMed

    Shima, Shuhei; Matsui, Hirokazu; Tahara, Satoshi; Imai, Ryozo

    2007-03-01

    Substantial levels of trehalose accumulate in bacteria, fungi, and invertebrates, where it serves as a storage carbohydrate or as a protectant against environmental stresses. In higher plants, trehalose is detected at fairly low levels; therefore, a regulatory or signaling function has been proposed for this molecule. In many organisms, trehalose-6-phosphate phosphatase is the enzyme governing the final step of trehalose biosynthesis. Here we report that OsTPP1 and OsTPP2 are the two major trehalose-6-phosphate phosphatase genes expressed in vegetative tissues of rice. Similar to results obtained from our previous OsTPP1 study, complementation analysis of a yeast trehalose-6-phosphate phosphatase mutant and activity measurement of the recombinant protein demonstrated that OsTPP2 encodes a functional trehalose-6-phosphate phosphatase enzyme. OsTPP2 expression is transiently induced in response to chilling and other abiotic stresses. Enzymatic characterization of recombinant OsTPP1 and OsTPP2 revealed stringent substrate specificity for trehalose 6-phosphate and about 10 times lower K(m) values for trehalose 6-phosphate as compared with trehalose-6-phosphate phosphatase enzymes from microorganisms. OsTPP1 and OsTPP2 also clearly contrasted with microbial enzymes, in that they are generally unstable, almost completely losing activity when subjected to heat treatment at 50 degrees C for 4 min. These characteristics of rice trehalose-6-phosphate phosphatase enzymes are consistent with very low cellular substrate concentration and tightly regulated gene expression. These data also support a plant-specific function of trehalose biosynthesis in response to environmental stresses.

  7. Feedback inhibition of starch degradation in Arabidopsis leaves mediated by trehalose 6-phosphate.

    PubMed

    Martins, Marina Camara Mattos; Hejazi, Mahdi; Fettke, Joerg; Steup, Martin; Feil, Regina; Krause, Ursula; Arrivault, Stéphanie; Vosloh, Daniel; Figueroa, Carlos María; Ivakov, Alexander; Yadav, Umesh Prasad; Piques, Maria; Metzner, Daniela; Stitt, Mark; Lunn, John Edward

    2013-11-01

    Many plants accumulate substantial starch reserves in their leaves during the day and remobilize them at night to provide carbon and energy for maintenance and growth. In this paper, we explore the role of a sugar-signaling metabolite, trehalose-6-phosphate (Tre6P), in regulating the accumulation and turnover of transitory starch in Arabidopsis (Arabidopsis thaliana) leaves. Ethanol-induced overexpression of trehalose-phosphate synthase during the day increased Tre6P levels up to 11-fold. There was a transient increase in the rate of starch accumulation in the middle of the day, but this was not linked to reductive activation of ADP-glucose pyrophosphorylase. A 2- to 3-fold increase in Tre6P during the night led to significant inhibition of starch degradation. Maltose and maltotriose did not accumulate, suggesting that Tre6P affects an early step in the pathway of starch degradation in the chloroplasts. Starch granules isolated from induced plants had a higher orthophosphate content than granules from noninduced control plants, consistent either with disruption of the phosphorylation-dephosphorylation cycle that is essential for efficient starch breakdown or with inhibition of starch hydrolysis by β-amylase. Nonaqueous fractionation of leaves showed that Tre6P is predominantly located in the cytosol, with estimated in vivo Tre6P concentrations of 4 to 7 µm in the cytosol, 0.2 to 0.5 µm in the chloroplasts, and 0.05 µm in the vacuole. It is proposed that Tre6P is a component in a signaling pathway that mediates the feedback regulation of starch breakdown by sucrose, potentially linking starch turnover to demand for sucrose by growing sink organs at night.

  8. Cloning and truncation modification of trehalose-6-phosphate synthase gene from Selaginella pulvinata.

    PubMed

    Zhao, Sheng-Mei; Fu, Feng-Ling; Gou, Lin; Wang, Han-Guang; He, Gang; Li, Wan-Chen

    2013-01-10

    A homologous sequence was amplified from resurrection plant Selaginella pulvinta by RACE technique, proved to be the full-length cDNA of trehalose-6-phosphate synthase gene by homologous alignment and yeast complementation assay, and nominated as SpTPS1 gene. The open reading frame of this gene was truncated 225bp at the 5'-end, resulting the N-terminal truncation modification of 75 amino acids for its encoding protein. The TPS1 deletion mutant strain YSH290 of the brewer's yeast transformed by the truncated gene SpTPS1Δ and its original full-length version restored growth on the medium with glucose as a sole carbon source and displayed growth curves with no significant difference, indicating their encoding proteins functioning as TPS enzyme. The TPS activity of the mutant strain transformed by the truncated gene SpTPS1Δ was about six fold higher than that transformed by its original version, reasoning that the extra N-terminal extension of the full-length amino acid sequence acts as an inhibitory domain to trehalose synthesis. However, the trehalose accumulation of the mutant strain transformed by the truncated gene SpTPS1Δ was only 8% higher than that transformed by its original version. This result is explained by the feedback balance of trehalose content coordinated by the comparative activities between trehalose synthase and trehalase. The truncated gene SpTPS1Δ is suggested to be used in transgenic operation, together with the inhibition of trehalase activity by the application of validamycin A or genetic deficiency of the endogenous trehalase gene, fo