Dissertations / Theses on the topic 'Glycolysis'
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1
Graham, James William Alexander. "Mitochondrial glycolysis in plants." Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445769.
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Hale, R. D. "Glycolysis in Crithidia fasciculata." Thesis, University of Liverpool, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234866.
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Robinson, Andrew James Cave. "Pyruvate kinase & glycolysis in potato." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335799.
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Pearce, Amanda K. "Regulation of glycolysis in Saccharomyces cerevisiae." Thesis, University of Aberdeen, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301297.
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This thesis extends the work of Crimmins (1995) on the control of glycolytic flux in yeast by the enzymes 6-phosphofructo-1-kinase and pyruvate kinase (Pyk1p). This study also examines the influence of Pf1kp and Pyk1p upon yeast resistance to the weak acid preservative, benzoic acid. In Saccharomyces cerevisiae, Pyk1p is encoded by PYK1, and the α and β subunits of Pf1kp are encoded by PFK1 and PFK2, respectively. To test the influence of these genes upon glycolytic control, an isogenic set of S. cerevisiae mutants were utilised in which PYK1, PFK1 and PFK2 expression is dependent on the PGK1 promoter. Increased Pf1k levels had little effect upon rates of glucose utilisation or ethanol production during fermentative growth. However, overexpressing Pyk1p resulted in an increased growth rate and an increase in glycolytic flux. This suggests that Pyk1p, but not Pf1kp, exerts some degree of control over the glycolytic flux under these conditions. The effects of reducing Pf1kp and Pyk1p levels were also studied by placing PYK1, PFK1 and PFK2 under the control of the weak PGK1Δuas promoter. The double Pf1kp mutant showed no significant changes in doubling time, ethanol production or glucose consumption. However, a mutant with a 3-fold reduction ion Pyk1p levels displayed slower growth rates and reduced glycolytic flux. In addition, there was an imbalance in the carbon flow in this mutant, with reductions in ethanol and glycerol production evident, along with increased TCA cycle activity. Hence, while Pf1kp levels did not affect cell physiology significantly under the conditions studied, reduced Pyk1p levels seemed to disturb glycolytic flux and carbon flow. Decreased Pf1kp levels caused an increase in the sensitivity of yeast cells to benzoate, whereas the Pyk1p mutant was not affected. This confirmed that benzoic acid specifically inhibits Pf1kp rather than glycolysis in general.
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Tandon, Preeti. "S6K1 mediates oncogenic glycolysis in Pten deficient leukemia." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1320682200.
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Xintaropoulou, Chrysi. "Targeting aerobic glycolysis in breast and ovarian cancer." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/29525.
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Cancer cells, unlike normal tissue, frequently rely on glycolysis for the production of energy and the metabolic intermediates required for their growth regardless of cellular oxygenation levels. This metabolic reconfiguration, termed the Warburg effect, provides a potential strategy to preferentially target tumours from a therapeutic perspective. The present study sought to investigate the glycolytic phenotype of breast and ovarian cancer, and assess the possibility of exploiting several glycolytic targets therapeutically. Initially the growth dependency of breast and ovarian cancer cells on the availability of glucose was established. An array of 10 compounds reported to inhibit key enzymes of the glycolytic pathway were investigated and compared against an extended panel of breast and ovarian cancer cell line models. All inhibitors investigated, targeted against multiple points of the pathway, were shown to block the glycolytic pathway as demonstrated by glucose accumulation in the culture media combined with decreased lactate secretion, and attenuated breast and ovarian cancer cell proliferation in a concentration dependent manner. Furthermore their mechanism of action was investigated by flow cytometric analysis and their antiproliferative effect was associated with induction of apoptosis and G0/G1 cell cycle arrest. The glycolytic inhibitors were further assessed in combination strategies with established chemotherapeutic and targeted agents and several synergistic interactions, characterised by low combination index values, were revealed. Among them, 3PO (a novel PFKFB3 inhibitor) enhanced the effect of cisplatin in both platinum sensitive and platinum resistant ovarian cancer cells suggesting a strategy for treatment of platinum resistant disease. Furthermore robust synergy was identified between IOM-1190 (a novel GLUT1 inhibitor) and metformin, an antidiabetic inhibitor of oxidative phosphorylation, resulting in strong inhibition of breast cancer cell growth. This combination is proposed for the treatment of highly aggressive triple negative breast tumours. An additional objective of this research was to investigate the effect of the oxygen level on sensitivity to glycolysis inhibition. Breast cancer cells were found to be more sensitive to glycolysis inhibition in high oxygen conditions. This enhanced resistance at low oxygen levels was associated with upregulation of the targeted glycolytic enzymes as demonstrated at both the mRNA (by gene expression microarray profiling, Illumina BeadArrays) and protein level (by Western blotting). Manipulation of LDHA (Lactate Dehydrogenase A) by siRNA knockdown provided further evidence that downregulation of this target was sufficient to significantly suppress breast cancer cell proliferation. Finally, the expression of selected glycolytic targets was examined in a clinical tissue microarray set of a large cohort of ovarian tumours using quantitative immunofluorescence technology, AQUA. The role of the glycolytic phenotype in ovarian cancer was suggested and interesting associations between the glycolytic profile and clear cell and endometrioid ovarian cancers revealed. Increased PKM2 (Pyruvate kinase isozyme M2) and LDHA expression were demonstrated in clear cell tumours and also low expression of these enzymes was significantly correlated with improved survival of endometrioid ovarian cancer patients. Taken together the findings of this study support the glycolytic pathway as a legitimate target for further investigation in breast and ovarian cancer treatment.
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Stefansson, G. "Effects of gases on post-mortem glycolysis in meats." Thesis, University of Leeds, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371847.
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Long, Heidi Sarah. "Glycolysis and the control of pulmonary tone during hypoxia." Thesis, King's College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250174.
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Shen, Qingwu. "AMP-activated protein kinase, postmortem glycolysis, and PSE meat." Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1338871331&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Nairn, Jacqueline. "Phosphoglycerate mutases from microorganisms." Thesis, University of Stirling, 1992. http://hdl.handle.net/1893/22851.
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Phosphoglycerate mutase catalyses the interconversion of 2-phosphoglycerate and 3-phosphoglycerate in the glycolytic/gluconeogenic pathways. There are two main types of phosphoglycerate mutase: 2,3-bisphosphoglycerate dependent and 2,3-bisphosphoglycerate independent. The enzyme from Saccharomyces cerevisiae has been extensively studied: the high resolution crystal structure of this tetrameric enzyme, subunit Mr 27,000, is known (Winn et al., 1981), the amino acid sequence has been determined (Fothergill and Harkins, 1982) and the gene encoding the enzyme has been isolated and sequenced (White and Fothergill-Gilmore, 1988). Phosphoglycerate mutase from the fission yeast, Schizosaccharomyces pombe, has been purified and partially characterised (Price et al., 1985; Johnson and Price, 1987). It is monomeric, of Mr 23,000, and the sequences of a number of peptides produced by digestion of this enzyme have been determined (Fothergill and Dunbar. unpublished). Alignment of these sequenced peptides with the sequence of S.cerevisiae phosphoglycerate mutase shows 40% identity and the conservation of a number of residues which are known to be essential to the activity of the S. cerevisia enzyme e. g. His-8, Arg-7, Ser-11. Thr-20 and Arg-59. Attempts were made to isolate and sequence the gene encoding S. pombe phosphoglycerate mutase. The S.cerevisiae phosphoglycerate mutase gene failed to detect gene sequence homologies in the S.pombe genome. An oligonucleotide, designed against part of the S.pombe phosphoglycerate mutase sequence (a stretch which was not homologous to the S. cerevisiae sequence) also failed to detect sequence homologies in the S.pombe genome. Thus under the conditions used, neither the S. cerevisiae gene nor the degenerate oligonucleotide appeared to be a suitable molecular probe to screen the S.pombe cDNA expression library in λgt11 (which was synthesised by V. Simanis). A polyclonal antibody against S.pombe phosphoglycerate mutase was prepared and used to screen the S. pombe cDNA expression library. A number of small identical clones were isolated and sequenced. the cDNA inserts encoded 69 residues and part of this sequence was similar to part of the sequence of phosphoglycerate mutase from other sources. Part of the sequence was also similar to a stretch of fructose-2,6-bisphosphatase sequence (fructose-2,6-bisphosphatase appears to be divergently related to phosphoglycerate mutase, Pilkis et al., 1987). A purification scheme for phosphoglycerate mutase from the prokaryote, Streptomyces coelicolor, has been devised. The N-terminal sequence of this enzyme was determined and confirmed that the gene isolated and sequenced by Peter White, encoded phosphoglycerate mutase from S. coelicolor. The enzyme was shown to be a tetramer with a subunit Mr of 29,000. S. coelicolor phosphoglycerate mutase was also shown to be partially 2,3-bisphosphoglycerate dependent.
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Rhoades, Ryan D. "Postmortem regulation of glycolysis by 6-phosphofructokinase in bovine muscle." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1204.
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This study was conducted to assess the regulation of glycolysis by 6phosphofructokinase (PFK) during the postmortem metabolism of beef muscle. In the first experiment, M. sternocephalicus pars mandibularis samples were excised from six randomly-selected steers. Two samples were obtained from each steer immediately postmortem; one sample was quickly immersed in liquid nitrogen and the other was stored at 4oC for 4 d. Glycogen concentrations decreased 45% from d 0 to d 4, and 39.6 ?mol/g of glycogen was still present in the tissue at d 4. Concentrations of free glucose increased (P < 0.001) from 0.84 ?mol/g at d 0 to 6.54 ?mol/g at d 4. Fructose-6-phosphate (F6P) and glucose-6-phosphate (G6P) increased (P < 0.001) from d 0 to d 4 (2.8-fold and 4.7-fold, respectively). Lactate began accumulating immediately (3.33 ?mol/g) and was elevated to 45.9 ?mol/g by d 4. Glycolytic potential was 34.4 ?mol/g higher (P < 0.05) when measured at d 0 than at d 4. The greatest activity of PFK was measured in fresh muscle extracts, between pH 7.4-7.8; by reducing the pH to 7.0, PFK activity was depressed by nearly 50% at 1 mM F6P.
In a second experiment, M. longissimus lumborum samples were excised at the 13th thoracic rib location from six randomly-selected steers. Samples were obtained at intervals ranging from 40 min to 24 h postmortem. Glycogen concentrations decreased 45% between 40 and 100 min, and tended (P ≤ 0.10) to decrease between 100 min and 24 h (from 47 to 32 ?mol/g). Concentrations of free glucose increased (P ≤ 0.009) from
1.0 ?mol/g at 40 min to 5.0 ?mol/g at 24 h. Concentrations of F6P and G6P increased dramatically after 100 min (muscle pH ≤ 6.5), whereas glycogen depletion appeared to halt by 100 min. Lactate began accumulating almost immediately and tripled in concentration by 24 h. The elevation of G6P and F6P, coupled with the pH sensitivity of PFK, indicate that the postmortem decline in pH ultimately inactivates PFK prior to glycogen depletion.
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Fiske, Brian Prescott. "Coordinated regulation of glycolysis and the folate one-carbon cycle." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/98628.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Biology, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references.
Rapid cell proliferation is characteristic of many biological systems, including cancer, normal development, and immune responses. At a basic level, proliferation requires that a cell synthesize a new copy of itself, with cell metabolism supplying the building blocks for new proteins, nucleic acids and lipids. Cancer and other proliferating cell types exhibit "aerobic glycolysis" characterized by elevated glucose uptake and conversion of glucose to lactate even in the presence of oxygen. Aerobic glycolysis is associated with anabolic reactions to generate new cellular material, but how aerobic glycolysis supports proliferative metabolism is not well understood. Pyruvate kinase (PK) catalyzes the last step in glycolysis, and while there is no evidence that PK activity is limiting for glycolysis, all proliferating cells express the PKM2 isoform of PK that is unique in having regulated activity which is decreased in the context of cellular proliferation. The simultaneous requirement for increased aerobic glycolysis and expression of the PKM2 isoform that is inhibited by growth signaling is a paradox, and it is unclear how elevated glucose metabolism enables rapid proliferation yet also requires decreased PKM2 activity. This thesis will explore two potential explanations for this paradox. The first hypothesizes the existence of an undiscovered enzyme that catalyzes a PK-like reaction, resolving the paradox by aligning increased flux through glycolysis with increased or unchanged activity of the PK step. The second hypothesis explores how PKM2 expression and PK inhibition supports proliferation by increasing serine synthesis from upstream glycolytic intermediates. This diverts one-carbon units into the folate pool to generate nucleotides via phosphoserine inhibition of SHMT1-mediated serine synthesis and one-carbon "wasting" in some cancer cells. We will also consider the reciprocal question of how folate one-carbon pool status in turn may regulate both PKM2 activity and glycolytic serine biosynthesis. The ability of PKM2 regulation to control folate metabolism for nucleotide synthesis explains for the first time at a mechanistic level one way that aerobic glycolysis promotes proliferative metabolism.
by Brian Prescott Fiske.
Ph. D.
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Du, Preez Franco B. "Comparative cross-species analysis of detailed kinetic models of glycolysis." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/1208.
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Thesis (PhD (Biochemistry))--University of Stellenbosch, 2009.ENGLISH ABSTRACT: With the recent advances in the field of molecular biology, there is an increased need to integrate data on the various constituents of the cell in kinetic models that can predict and describe cellular behavior. When working towards a description of the entire cell using such kinetic models, the question arises: How do we compare different models for a given biological network? This is the central question addressed in my thesis and I developed and applied mathematical and computational methods for comparing dozens of existing models of erythrocyte and yeast glycolysis. To compare the steady-state behavior in models of erythrocyte glycolysis, I focussed on the function of the pathway, which is to supply the cell with Gibbs-free energy (γ- phosphate of ATP). I used supply-demand analysis in the framework of metabolic control analysis to make this comparison, which revealed that the ATP concentrations were homeostatically buffered at varying supply rates. I also applied this approach to compare steady-state behavior in models of yeast glycolysis, finding that they were not necessarily optimized for homeostatic maintenance of the ATP concentration and that in models for this organism the rate of ATP production is often determined by the supply reactions of glycolysis. In addition, I tested whether a kinetic model can describe novel behavior if it is adjusted to conditions different from those for which the model was originally constructed. More specifically, using a model of steady-state yeast glycolysis, I showed that small adjustments to the original enzyme concentrations are enough to obtain an oscillating model, which shows a remarkable resemblance to the experimentally observed oscillations. Importantly, some of these enzyme concentrations changes are known to occur during the pre-treatment of the cells which is necessary to obtain oscillatory behavior. To the best of my knowledge, the resulting model is the first detailed kinetic model that describes the experimentally observed strong synchronization of glycolytic oscillations in yeast populations. To analyze the dynamic behavior of yeast glycolytic models and to compare different models in terms of dynamics, I introduced a framework used in physics and engineering to create a vector based, two dimensional graphical representation of the oscillating metabolites and reactions of glycolysis. Not only was it possible to make a concise comparison of the set of models, but with the method I could also quantify the contribution of the interactions in the network to the transduction of the oscillations. Furthermore I could distinguish between different mechanisms of oscillation for each of the models, and demonstrated how the framework can be used to create such representations for experimental data sets.
AFRIKAANSE OPSOMMING: Met die onlangse vooruitgang in die veld van molekulere biologie, is daar ?n toenemende behoefte om data rakende die verskeie komponente van die sel in kinetiese modelle te integreer, om sodanig selgedrag te voorspel en te beskryf. As daar gepoog word om ’n beskrywing van die sel as geheel te verkry d.m.v. sulke kinetiese modelle, onstaan die vraag: Hoe vergelyk ons verskillende modelle van ’n gegewe biologiese netwerk? Dit is die sentrale vraag wat my tesis aanspreek en ek het wiskundige en numeriese metodes ontwikkel en toegepas om talle bestaande modelle van gis- en eritrosietglikolise te vergelyk. Om die bestendige-toestand gedrag in modelle van eritrosietglikolise te vergelyk, het ek gefokus op die funksie van die padweg, naamlik om die sel met Gibbs-vrye energie (γ-fosfaat van ATP) te voorsien. Ek het vraag-aanbod analiese in die raamwerk van metaboliese kontrole analiese gebruik om hierdie vergelyking te maak, wat getoon het dat die ATP konsentrasies homeostaties gebuffer was by verskillende aanbod tempos. Ek het ook hierdie aanpak gebruik om die bestendige-toestand gedrag in modelle van gisglikolise te vergelyk, en het bevind dat hulle nie noodwendig geoptimiseer is om ?n homeostatiese balans in die ATP konsentrasie te handhaaf nie, en dat in modelle vir hierdie organisme, die tempo van ATP produksie dikwels bepaal word deur die aanbod reaksies van glikoliese. Ek het verder ook bepaal of so ?n kinetiese model nuwe soorte gedrag kan beskryf, as dit aangepas word aan omstandighede wat verskil van dié waarvoor die model oorspronklik gekonstrueer was. Meer spesifiek, deur ?n model van bestendige-toestand gisglikolise te gebruik, kon ek wys dat klein veranderinge aan die oorspronkline ensiem konsentrasies genoeg was om ?n ossilerende model te verkry, wat opmerklik ooreenstem met die eksperimenteel waargenome ossilasies. Let ook daarop dat sommige van hierdie ensiem konsentrasie veranderinge plaasvind tydens die voorafbehandeling van die selle, wat essensieel is om die ossilasies waar te neem. Tot die beste van my kennis is die model wat ek met hierdie prosedures verkry het, die eerste gedetaileerde kinetiese model wat die eksperimenteel waargenome sterk sinkronisasie in ossilerende gis populasies voorspel. Om gis glikolitiese modelle te vergelyk in terme van hul dinamiese gedrag, het ek ?n raamwerk wat in fisika en ingeneurswese gebruik word, ingespan om ?n vektor-gebasseerde, twee dimensionele grafiese voorstelling van die ossilerende metaboliete en reaksies te maak. Hierdie raamwerk het dit nie net moontlik gemaak om ?n kompakte vergelyking van ?n stel modelle te maak nie, maar ek kon ook die bydrae van interaksies in die netwerk tot transduksie van die ossilasies kwantifiseer. Ek kon verder onderskeid tref tussen die verskillende ossilasiemeganismes vir elk van die modelle, en het ook gedemonstreer hoe die raamwerk gebruik kan word om sulke voorstellings vir eksperimentele datastelle te skep.
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Pasupuleti, Vinay. "Role of Glycolysis and Respiration in Sperm Metabolism and Motility." Kent State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=kent1195536178.
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Khatri, Shikha. "FOXO3a Regulates Glycolysis via Transcriptional Control of Tumor Suppressor TSC1." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1282570293.
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ABDALI, ANAHITA. "INHIBITION OF ANGIOGENESIS USING GLYCOLYSIS INHIBITORS: AN IN VITRO STUDY." Doctoral thesis, Università degli Studi di Milano, 2019. http://hdl.handle.net/2434/640647.
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Aberrant angiogenesis contributes to many pathophysiological conditions such as cancer and diabetes mellitus. Current anti-angiogenic therapies aim at targeting key angiogenic growth factors or their endothelial cell-expressed receptors including VEGF and VEGFRs. This strategy, however, often fails to render sustained responses with minimal increased survival rate in treatment of several cancers due to toxicity and drug resistance. A novel approach in the angiogenic field is by indirect and partial inhibition of glycolysis by targeting phosphofructokinase-fructose-2,6-bisphophatase 3 (PFKFB3).
Neo-angiogenesis by endothelial cells (ECs) is regulated by metabolism: mainly glycolysis. The lead anti-glycolytic compound, 3-(3-pyridinyl)-1-(4-pyridinyl)-2-propen-1-one (3PO), was identified as a promising compound to reduce pathological angiogenesis and tumor growth. However, doubts has risen about its true mechanism of action. We confirm that 3PO partially reduced glycolysis, EC migration enough to impair vessel sprouting. Further, we demonstrate that these effects cannot be attributed to its’ suggested binding to the target PFKFB3. 3PO does not bind to PFKFB3 and does not inhibit PFKFB3 kinase activity. Finally, 3PO caused intracellular acidification caused by lactate accumulation in ECs. In another study we have observed a strong transcriptional regulation of these transporters by 3PO. For these reasons, we speculate that 3PO regulate activity of lactate transporters, monocarboxylate transporter 1 (MCT1) and MCT4.
We next identified two selective PFKFB3 inhibitors, PA-1 and PA-2, with validated binding and potent inhibitory activity towards PFKFB3. We demonstrate that these inhibitors reduced glycolysis to similar levels as silencing of PFKFB3 or using 3PO. In turn, formation capillary-like structures was impaired by inhibiting EC proliferation and migration. PFKFB3-mediated inhibition of glycolysis resulted in inhibition of transcription and activity of matrix metalloproteases (MMP)-2 and MMP-9. Furthermore, blockade of PFKFB3 with PA compounds also acted on the VEGFA/VEGFR2 axis and reduced angiogenic activation in inflamed ECs. These insights offer promising opportunities to treat aberrant angiogenesis and vasculogenesis.
Taken together, our research has provided two selective PFKFB3 inhibitors to suppress neo-angiogenesis. Derivatives of these compounds are being studied in preclinical atherosclerotic models characterized by intraplaque angiogenesis. Future research will provide insight into their potential to promote atherosclerotic plaque stability.
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Doyen, Jérôme. "Rôle des protéines de régulation du pH intracellulaire et du métabolisme énergétique dans les carcinomes du sein triple négatif." Thesis, Nice, 2013. http://www.theses.fr/2013NICE4147/document.
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Les cancers agressifs se caractérisent par un métabolisme glycolytique exacerbé avec surexpression de protéines assurant le contrôle du pH intracellulaire par l’export efficace des déchets métaboliques acides (par CAIX, CAXII, MCT1 et MCT4 entre autres). Les cancers du sein dit "triple négatif" (sans expression des récepteurs à l'estrogène, progestérone et Her-2) présentent une consommation augmentée de glucose et un plus mauvais pronostic en comparaison avec les autres cancers du sein. L'analyse immunohistochimique de l'expression des protéines glycolytiques d'une cohorte de 159 patientes TNEG a montré que MCT4 était prédictif de la survenue de métastases et de décès. Le ciblage in vitro de MCT4 par la technique des Zinc Finger Nucléases (ZFN) a eu un effet anti-prolifératif. L'efficacité était toutefois maximale lors du ciblage combiné de MCT1 (inhibiteur pharmacologique), MCT4 et de la respiration mitochondriale par la phenformine dans la lignée de cancer TNEG Hs578t. Cette étude montre donc que le ciblage des protéines glycolytiques pourrait être une piste intéressante dans le traitement des cancers du sein TNEG. Un autre travail a permis d'exploiter le ciblage des protéines glycolytiques, notamment CAIX et CAXII, pour augmenter in vitro et in vivo la radiosensibilité de lignées de cancer colorectal tout en démontrant un mécanisme original de radiosensibilisation, via l'acidification intracellulaire. Enfin, nous avons mis en évidence l'importance de l'hypoxamiR miR210 dans la radiorésistance de lignées de cancer du poumon, avec une radiorésistance semblant dépasser l'effet oxygèneAgressive cancers often harbor an exacerbated glycolytic metabolism with overexpression of proteins that maintain intracellular pH by extruding metabolic acid waste (via CAIX, CAXII, MCT1 and MCT4 among others). The "triple-negative" breast cancers (with no expression of estrogen, progesteron and Her-2 receptors) have an increased consumption of glucose and worse prognosis in comparison with other breast cancers. Immunohistochemical analysis of glycolytic proteins among 159 patients with TNEG breast cancer, showed that MCT4 was predictive for metastasis and death occurence. In vitro targeting of MCT4 by Zinc Finger Nuclease (ZFN) technique demonstrated an anti-proliferative effect. However, the maximal anti-proliferative effect was observed with the combination of MCT4/MCT1 (by pharmacological inhibition) and mitochondrial respiration by phenformine in the Hs578t TNEG cell line. This study demonstrated that targeting glycolytic protein could have a therapeutic effect in TNEG breast cancers. Another study also use targeting of glycolytic protein such as CAIX and CAXII to increase in vitro and in vivo radiosensitivity of colorectal cell lines while demonstrating an original mechanism of radiosensitization by increasing intracellular acidosis. Finally we demonstrated that the hypoxamiR miR210 was involved in the radioresistance of lung cancer cell line with a stronger impact than the oxygen effect
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Keon, Claudia Anne. "Myocardial energy transduction in the isolated working rat heart." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244563.
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Rayner, Mark. "Purification anad characterisation of pig heart 6-phosphofructo-2-kinase/ fructose-2,6-bisphosphatase." Thesis, University of Liverpool, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261842.
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Yang, Min. "Synthesis of 5 thioglucose derivatives in the carbohydrate metabolic pathways in lactic acid bacteria." Thesis, University of Huddersfield, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274227.
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Hernandez, Mark J. "Caveolin-1 A scaffold for microcompartmental organization of membrane-associated glycolysis." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/6007.
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Thesis (Ph. D.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. "August 2007" Includes bibliographical references.
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Anderson, Roxette Dianne. "Improving breast cancer therapy through oestrone analogue and glycolysis inhibitor synergism." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/63050.
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Introduction: In South Africa, breast cancer has the highest prevalence with a life time risk of
1 in every 9 women being diagnosed annually. There are four sub-types of breast cancer and
according to the stage of the cancer, various treatment regimens are prescribed. A major obstacle
is that majority of cancers have developed multi-drug resistance and new treatment regimens
need to be developed in order to obtain therapeutic efficacy. Cancer cells use aerobic glycolytic
metabolism for energy generation and inhibition of this pathway increases sensitivity of the cells
to anti-neoplasic treatments. 2-Deoxyglucose (2-DG) competes with and inhibits glucose uptake
inhibiting the glycolytic pathway which can result in depolarisation of the mitochondrial
membrane potential releasing cytochrome c. Two 2-Methoxyestradiol (2-ME) derivatives, ESE-
15-ol and ESE-16 have shown to be promising anti-cancer agents and combination therapy could
allow the use of these compounds with a decreased side effect profile. The combination of these
compounds with 2-DG was therefore investigated.
Aim: To investigate combinations of two oestrone analogues and the glycolysis inhibitor 2-
deoxyglucose for potential synergistic effects using a cell enumeration assay, mitochondrial
membrane potential and cell cycle analysis, on breast cancer cells in an in vitro setting. Cell
apoptosis, necrosis and autophagy pathways were assessed to indicate the mechanism of
cytotoxicity.
Methods: The breast cancer MCF-7 and non-tumorigenic MCF-12A cell line were used. Cells
were exposed to ESE-15-ol, ESE-16 and 2-DG alone and in combination. Mechanistic studies
were performed using the various research methodologies including the sulforhodamine B assay
for cell enumeration, Annexin-V FITC and propidium iodide labeling for apoptosis/necrosis
studies, PlasDIC and light microscopy for morphological analysis, propidium iodide staining for
cell cycle progression, JC-1 for mitochondrial membrane potential studies, transmission electron
microscopy and western blotting for the analysis of autophagy.
Results: A GI50 of 34.1 nM was reported for MCF-7 cells after treatment with ESE-15-ol, 141
nM for ESE-16 and 1.3 mM 2-DG. The GI50 of ESE-15-ol treated MCF-12A cells was 141 nM,
140.1 nM for ESE-16 treated cells and 1.7 mM for 2-DG. ESE-16 had the greatest effect on cell
viability in MCF-7 cells and a shift from an inhibitory effect to the initiation of cell death was
evident after treatment of 100 nM of ESE-15-ol and ESE-16. 2-DG had a lower cytotoxic effect
than the oestrone analogues. The MCF-12A cell line was less susceptible to the experimental
compounds. The combination of the oestrone analogues with 2-DG elicited a greater effect on cell enumeration than each of the compounds alone with a less pronounced effect on the MCF-
12A cell line in comparison to the MCF-7 cells. The experimental compounds initiated apoptosis
with ESE-16 eliciting a greater effect than ESE-15-ol. The combination of the oestrone analogues
with 2-DG resulted in increased apoptosis in contrast to the compounds alone. ESE-16 alone and
in combination with 2-DG lead to the most prominent morphological changes, with ESE-15-ol
decreasing cell density slightly. The combination of ESE-15-ol with 2-DG decreased cell density
with membrane blebbing apparent. The MCF-12A cell line was less susceptible to morphological
changes after treatment of ESE-15-ol with 2-DG however ESE-16 and the combination with 2-
DG resulted in similar attributes seen in MCF-7 treated cells. ESE-15-ol resulted in accumulation
of cells in the G2 cell cycle phase which was further amplified after the combination of 2-DG.
A sub-G1 accumulation was observed after treatment with ESE-16 with a shift to a G2
accumulation after the combined treatment of ESE-16 with 2-DG. After 48 hours, ESE-15-ol
alone and in combination with 2-DG on MCF-7 cells resulted in depolarisation of the
mitochondrial membrane. A slight decrease in the membrane potential was observed after
treatment with ESE-16 and this was further increased after the combined treatment of ESE-16
with 2-DG. The MCF-12A were less susceptible after 24 hour treatment than 48 hour exposure
of the experimental compounds. The presence of autophagic-like vacuoles were apparent in all
treatment groups as well as the increased expression of LC3-II.
Conclusion: The combined treatment of synthetic oestrone analogues with 2-DG displayed
greater therapeutic efficacy than each of the compounds alone. As a result, the apoptotic and
autophagic pathways were induced and a shift in cell cycle progression was observed.
Mitochondrial involvement was apparent and the compounds significantly affected cell viability.
This suggests that the combinations between the antimitotic oestrone analogues and glycolysis
inhibitor 2-DG act synergistically to induce apoptosis and autophagy in MCF-7 breast cancer
cells.Dissertation (MSc)--University of Pretoria, 2017.
Pharmacology
MSc
Unrestricted
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Yuan, Fang. "DIFFERENTIAL EFFECTS OF GROWTH FACTORS ON GLYCOLYSIS IN OVARIAN CANCER CELLS." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/466.
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Lysophosphatidic acid (LPA), a naturally-occurring, simple phospholipid, is present at elevated levels in the blood and ascites of ovarian cancer patients. LPA is a ligand of seven cell surface G protein-coupled receptors. It has been known as an oncogenic growth factor in ovarian cancer and other types of human malignancies. However, the precise biological functions of LPA in ovarian oncogenesis remain to be fully elucidated. Our laboratory is interested in studying the potential role of LPA, as a tumor microenvironment factor, in regulation of cancer cell metabolism. A fundamental change associated with most cancer is the switch of glucose metabolism from mitochondrial oxidative phosphorylation to aerobic glycolysis, a phenomenon described by Otto Warburg nearly a century ago. This seems to be necessary to meet bioenergetic and biosynthetic demands of rapidly dividing tumor cells. However, the mechanism underlying the switch from aerobic respiration to aerobic glycolysis in cancer cells remains poorly understood. In this thesis project, my goal was to explore the effect of LPA on glycolysis and to compare LPA with other important growth factors in their capability to promote the glycolytic pathway in ovarian cancer cells. We demonstrated that LPA stimulated aerobic glycolysis as well as cell proliferation in ovarian cancer cell lines. The two parallel responses were LPA dose dependent. To determine whether LPA is unique in driving glycolysis, we compared the effect of LPA with other growth factors, including EGF, insulin and IGF-1 which are all involved in pathogenesis of ovarian cancer. While doses of these growth factors could be adjusted to achieve similar levels of cell proliferation, LPA and EGF were much more potent than insulin and IGF-1 in stimulation of glycolytic flux and lactate production. Therefore, we identified LPA and EGF as highly glycolytic factors relevant to the development and maintenance of the glycolytic phenotype of ovarian cancer cells. The next part of my study was focused on the molecular mechanism for the differential effects of LPA, EGF, insulin and IGF-1 on glycolytic metabolism. We used the glucose metabolism RT-PCR array to profile expression of glycolytic genes. The most remarkable change induced by LPA and EGF was the robust induction of hexokinase 2 (HK2) that stimulates irreversible entry of glucose to the glycolytic pathway. However, insulin and IGF-1 only weakly induced HK2 expression. Further experimental evidence using HK2 inhibitors indicated that HK2 up-regulation was the critical mediator of LPA-induced glycolysis. Further, the cells grown in LPA and EGF-stimulated conditions appear to show larger volume compared to insulin and IGF-1-treated cells, consistent with the hypothesis that active glycolysis contributes to biosynthetic processes to maintain cell sizes. Taken together, these findings of the current study revealed high glycolytic effects of LPA and EGF in ovarian cancer and the underlying HK2-mediated mechanism that distinguishes LPA and EGF from other growth factors such as insulin and IGF-1.
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Borges, Figueiredo Ana Leonor. "Control of cell specification and migration during early frog development by PFKFB4, a key glycolysis regulator." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112107.
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L’ectoderme embryonnaire devient spécifié en ectoderme non-neural, plaque neurale et bordure neurale à la fin de la gastrulation. Les cellules de bordure neurale sont les progéniteurs de la crête neurale et des placodes. La crête neurale est une population transitoire de cellules multipotentes, qui se forme au cours de la neurulation. Quand les bourrelets neuraux s’élèvent pour former le tube neural, les cellules de la crête neurale subissent une transition épithélio-mésenchymateuse, migrent dans l'ensemble du corps pour atteindre leur destination finale et se différencier. La crête neurale donne naissance à de multiples dérivés tels que les neurones et les cellules gliales du système nerveux périphérique, le cartilage et les os du visage, ou encore les mélanocytes. Des régulations complexes, impliquant de nombreuses signalisations et la transcription de gènes-clé, orchestrent ces événements. Cependant, les premières étapes menant à la formation de la crête neurale et à la spécification précoce de la bordure neurale sont encore peu comprises. Nous avons analysé le transcriptome de la crête neurale d'embryon de l'amphibien Xenopus laevis, à la recherche de nouveaux régulateurs des premières étapes de la formation de la crête neurale. Nous avons constaté que le régulateur de la glycolyse PFKFB4, est exprimé dans l’ectoderme dorsal de la jeune gastrula et dans les cellules de la crête neurale. Ici, nous démontrons que PFKFB4 régule la spécification de l’ectoderme via la voie de signalisation Akt, indépendamment de la glycolyse, démontrant ainsi la première fonction non-glycolytique des enzymes PFKFB. En outre, cette régulation est essentielle pour permettre aux progéniteurs de l'ectoderme d’être spécifiés en plaque neurale, crête neurale, placodes ou ectoderme non neural, mettant en évidence un nouveau point de contrôle de développement. De plus, nous démontrons que PFKFB4 régule des étapes ultérieures de la formation de la crête neurale. Notre travail met en évidence que les régulateurs du métabolisme cellulaire possèdent des fonctions non-métaboliques pour contrôler des étapes de développement au cours du développement embryonnaireEmbryonic ectoderm becomes specified into non-neural ectoderm, neural plate and neural border at the end of gastrulation. Neural border cells are the progenitors of the neural crest and placodes. The neural crest is a transient population of multipotent cells, which forms during neurulation. As the neural border elevates to form the neural tube, neural crest cells undergo an epithelial to mesenchymal transition, migrate extensively into the whole body to reach their final destinations and differentiate. Neural crest gives rise to multiple derivatives such as neurons and glia, facial cartilage, bones, melanocytes and sympatho-adrenal cells. A complex interplay of signaling and transcriptional regulations orchestrates these early patterning events. However, the first steps leading to NC formation and early specification at the NB are less understood. We analysed the NC transcriptome of frog embryos, to look for novel regulators of the early steps of NC formation. We found that the well-known glycolysis regulator PFKFB4, is expressed in early gastrula dorsal ectoderm, and in neurula neural crest cells. Here, we demonstrate that PFKFB4 regulates ectoderm specification via Akt signaling independently of glycolysis, thus demonstrating the first non-glycolytic function of PFKFB enzymes. Moreover, this regulation is essential to allow ectoderm embryonic progenitors to be patterned into neural plate, neural crest, placodes and definitive ectoderm, highlighting a novel developmental checkpoint. Moreover, we also demonstrate that PFKFB4 regulates later steps of neural crest formation. Our work highlights that regulators of cell metabolism accumulate non-metabolic related functions to control developmental steps during embryonic development
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Benton, Geoffrey Marsing. "Aerobic glycolysis: A novel signature of premalignancy in disease-free breast tissue." Diss., Search in ProQuest Dissertations & Theses. UC Only. Search in ProQuest Dissertations & Theses. UC Only, 2010. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3390032.
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Nowicki, Matthew William. "Development of lead compoundsfor trypanocidal drugs based on inhibitors of parasite glycolysis." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/15540.
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Kelly, Annemarie. "The developmental potential of embryos and cells that are deficient in glycolysis." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/20602.
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Previous work showed that mouse embryos homozygous for a null allele of the gene that encodes the glycolytic enzyme, glucose phosphate isomerase (GPI), died shortly after implantation. Although the homozygous GPI null embryos cannot produce their own GPI, because they lack the appropriate gene, they survived until 7.5 - 8.5 days (West el al, 1990) and some extraembryonic tissues survived until 10.5 days. A histological study was undertaken to determine when the first signs of abnormality become apparent in the dying homozygous GPI null embryos. The critical time period for these mutant embryos was found to be between 6.5 days and 7.5 days. This is after the oocyte coded GPI is exhausted so the embryo has to rely on it's own production of the enzyme. At this stage the embryo is implanting under relatively anaerobic conditions because the placenta has not yet formed. The mutant embryos fail to gastrulate properly and produce only a small amount of mesoderm. The abnormally developed egg cylinder expands to form an empty sac-like structure. The membrane that resembles the yolk sac is in fact comprised of extraembryonic ectoderm and extraembryonic endoderm. Aggregation chimeras were produced between homozygous GPI null embryos and normal embryos to examine whether homozygous GPI null cells could survive for longer when combined with normal cells. Because the homozygous GPI null embryos are embryo lethal, two heterozygotes were intercrossed to produce embryos, 25% of which should be homozygous for the null allele. All of the embryos produced from the intercrossing of the heterozygotes were aggregated to normal 8 - cell embryos.
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Albers, Renee Elizabeth. "Glycolytic Metabolism and Pregnancy Parameters in the Murine Placenta." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1513781057460423.
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Saeedi, Ramesh. "AMP-activated protein kinase and hypertrophic remodeling of heart muscle cells." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/4065.
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Introduction: Cardiac hypertrophy is an adaptive response to increased myocardial workload that becomes maladaptive when hypertrophied hearts are exposed to an acute metabolic stress, such as ischemia/reperfusion. Acceleration of glycolysis occurs as part of the hypertrophic response and may be maladaptive because it enhances glycolytic metabolite accumulation and proton production. Activation of AMP-activated protein kinase (AMPK), a kinase involved in the regulation of energy metabolism, is proposed as a mechanism for the acceleration of glycolysis in hypertrophied hearts. However, this concept has not yet been proven conclusively. Additionally, several studies suggest that AMPK is involved in hypertrophic remodeling of the heart by influencing cardiac myocyte growth, a suggestion that remains controversial.
Hypothesis: AMPK mediates hypertrophic remodeling in response to pressure overload. Specifically, AMPK activation is a cellular signal responsible for accelerated rates of glycolysis in hypertrophied hearts. Additionally, AMPK influences myocardial structural remodeling and gene expression by limiting hypertrophic growth.
Experimental Approach: To test this hypothesis, H9c2 cells, derived from embryonic rat hearts, were treated with (1 µM) arginine vasopressin (AVP) to induce hypertrophy. Substrate utilization was measured and the effects of AMPK inhibition by either Compound C or by adenovirus-mediated transfer of dominant negative AMPK were determined. Subsequently, adenovirus-mediated transfer of constitutively active form of AMPK (CA-AMPK) was expressed in H9c2 to specifically increase AMPK activity and, thereby, further characterize the role of AMPK in hypertrophic remodeling.
Results: AVP induced a metabolic profile in hypertrophied H9c2 cells similar to that in intact hypertrophied hearts. Glycolysis was accelerated and palmitate oxidation was reduced with no significant alteration in glucose oxidation. These changes were associated with AMPK activation, and inhibition of AMPK ameliorated but did not normalize the hypertrophy-associated increase in glycolysis. CA-AMPK stimulated both glycolysis and fatty acid oxidation, and also increased protein synthesis and content. Howver, CA-AMPK did not induce a pathological hypertrophic phenotype as assessed by atrial natriuretic peptide expression.
Conclusion: Acceleration of glycolysis in AVP-treated hypertrophied heart muscle cells is partially dependent on AMPK. AMPK is a positive regulator of cell growth in these cells, but does not induce pathological hypertrophy when acting alone.
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Rypniewski, W. R. "The structure of unliganded E. coli phosphofructokinase." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233316.
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The allosteric phosphofructokinase from E. coli crystallized in the absence of ligands. X-ray diffraction data were collected to 2.4 aa, AA resolution and the structure was solved by the method of molecular replacement, using the model of the liganded R-state of the enzyme. The atomic model was refined by rigid body refinement and by the least-squares method of Hendrickson and Konnert. The final structure is compared to the high resolution model of the liganded, active form of the enzyme and to the low resolution structure of the inhibited phosphofructokinase from B. stearothermophilus. It is found that the quaternary structure of the unliganded model is more similar to the liganded, active form than to the inhibited T-state of B. stearothermophilus pfk. There are however considerable differences in the tertiary and quaternary structures, apparently resulting from ligand binding. These changes are not localised to the binding sites. The overall change, though to result mainly from the binding of the activators, is consistent with the closing of the active site observed in the structure of the active state. The ways in which the ligand binding could bring about these changes are considered. The possible effect of the changes on the enzyme activity are discussed. It is possible that the structure represents an inactive T-state, different from that in the presence of inhibitors. Whatever the exact interpretation it is clear that the structure shows considerable flexibility suggesting that the two-state allosteric model is an oversimplification.
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Dancer, Jane Elizabeth. "The role of pyrophosphate:fructose 6-phosphate-1-phosphotransferase in plants." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330176.
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Elgin, Jennifer May. "Determining the Underlying Factors of Fresh Ham Color Variation." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/91406.
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Consumers associate meat color with quality. In some cases, especially in fresh and cured hams, the surface of a ham, whole, boneless or sectioned and formed displays a color gradient, which is unsightly and generally is considered of lower quality and must be discounted or processed different where color is less critical to the ultimate value of the resulting product. This disparity in color uniformity across fresh and cured products is sometimes known as two-toning and is most often found in the semimembranosus (SM) and associated muscles of fresh hams and is exacerbated with curing. The underlying color of fresh meat may be a function of postmortem metabolism or the underlying characteristics of those muscles involved. Therefore, the objective of this study is to determine the changes in underlying muscle type and postmortem metabolism in those muscles responsible for fresh ham color variation. Semimembranosus (SM) muscles of 15 mixed bred pigs were collected at 30 min and 1440 min postmortem, and muscle color was determined and muscles were collected and snap frozen for various energy metabolism analyses. Differences in color (L*, a* and b*) were noted across the face of the muscle by zone and time (P < 0.0001) but no differences were detected in pH and lactate, glucose, glucose-6-phosphate, and glycogen metabolisms. Glycolytic potential was also measured on a lactate basis and showed no differences across zone (P = 0.0746) but increased over time (P < 0.006). Lactate and pH were plotted and showed a linear relationship linear relationship (R2 = 0.928337) at 30 min (P < 0.0001) and at 1440 min (R2 = 0.161412; P < 0.0015). Muscle type characteristics showed no difference between zones and time. Buffering capacity showed a significant difference at pH 6 (P < 0.0359) and with time across all pH measured (P < 0.0001). These data suggest inherent differences, such as location and function, in the semimembranosus muscle may be more critical in developing fresh color than aberrations in postmortem metabolism.Master of Science
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Baltan, Selva. "Long-term potentiation induced by temporary block of glycolysis in CA1 hippocampal neurons." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0016/NQ44609.pdf.
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Crimmins, Kay. "The significance of genetic regulation in the control of glycolysis in Saccharomyces cerevisiae." Thesis, University of Aberdeen, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320258.
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The aim of this work was to establish the relative contribution of genetic regulation of the PYK1, PFK1 and PFK2 genes to the control of glycolysis. A series of isogenic mutant strains were constructed where the promoters and 5' untranslated sequences of the PYK1, PFK1 and PFK2 genes were replaced with those from PGK1. In addition , a second series of mutant strains were constructed where synthesis of Pyk1p and Pflkp was driven by the PGK1Δuas promoter. These latter series of mutants were designed to contain weak expression of Pyklp and Pflkp. Analysis of UKC1 (PGK::PYK1) in shake flask cultures revealed similar growth rates on glucose and on lactate and similar rates of ethanol production and glucose consumption to those of the wild-type strain. This suggested that the native genetic regulation did not appear to play a significant role in the control of glycolysis. Nonetheless, analysis of this strain in the fermentor revealed that genetic regulation of PYK1 may be important in co-ordinating Pyk1p synthesis, under the conditions studied. Analysis of YKC11 (PGKΔuas::PYK1) in both shake flask and fermentor experiments showed that genetic control was important in maintaining Pyk1p levels in order to sustain glycolytic flux. Shake flask analysis of the single and double PFK mutants under the control of the PGK1 promoter revealed that the genetic regulation of the PFK1 and PFK2 genes did not appear to be important in the control of glycolysis. Weak expression of the PFK1 and PFK2 genes, under the control of the PGKΔuas promoter showed the importance of genetic regulation in maintaining Pflkp levels to support glycolytic flux, under the conditions studied.
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Eicher, Johann Josef. "Understanding glycolysis in Escherichia coli : a systems approach using nuclear magnetic resonance spectroscopy." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85730.
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Thesis (PhD)--Stellenbosch University, 2013.ENGLISH ABSTRACT: This dissertation explores the behaviour and regulation of central carbon metabolism in Escherichia coli K12 W3110 under fermentative microaerobic conditions. To achieve this, an integrative systems modelling approach was adopted, which is introduced in Chapter 1 along with a review of metabolism in E. coli. An open-source software suite NMRPy, developed using the Python programming language, is presented in Chapter 2. NMRPy provides a host functions for basic processing, analysis and visualisation of Nuclear Magnetic Resonance (NMR) spectroscopy data. In addition to this, NMRPy offers specialised functions for the deconvolution of arrayed reaction time series, which proved indispensable to the research presented in this dissertation. NMRPy presents an easy to use, extensible tool for both routine and advanced use. In Chapter 3, a novel methodology is presented which was developed for the effective and comprehensive determination of enzyme kinetic parameters for systems biology using NMR. In contrast to traditional enzyme kinetic assay methods, this new methodology is less labour-intensive and yields significantly more information per experiment. By fitting kinetic equations to real time NMR data, dynamic changes in substrates, products and allosteric modifiers are quantified and allowed to inform the parameter fitting procedure. These data contain information on cooperative substrate binding, reversibility, product inhibition and allosteric effects. The proposed methodology is applied to the study of the first two enzymes of the glycolytic pathway. In Chapter 4, the construction, parameterisation and validation of a number of kinetic models of glycolysis in E. coli under microaerobic conditions is detailed. To model the lower half of glycolysis, a similar technique was adopted as in Chapter 3, in which models representing the reactions from triosephosphate isomerase to pyruvate kinase were parameterised by fitting them to a collection of 31P NMR reaction time series. This approach extends the methodology to enzyme sub-networks, yielding data that encompass the full complexity of the network regulatory interactions. The verified kinetic models were subjected to scrutiny, the results of which are presented in Chapter 5. The value of the modelling approach is demonstrated by the ease with which cumbersome in vivo experiments can be performed in silico. A structural analysis of the model topology was conducted, elucidating the elementary flux modes of fermentative glycolysis in E. coli, and identifying a futile cycle around PEP carboxylase and PEP carboxykinase. Model steady-state behaviour and control properties were explored in silico under various degrees of ATP demand and oxygen availability and a number of hypotheses are presented, explaining the regulation of free energy in E. coli, and the metabolic responses of E. coli to changing redox demands. Amongst other things, the results demonstrated that the glucose importing phosphoenolpyruvate: phosphotransferase pathway controlled glycolytic flux, and that under microaerobic conditions E. coli is able to regulate redox balance not only by balancing flux between acetate and ethanol, but also by altering the balance of flux between acetate and lactate at the pyruvate formate lyase/lactate dehydrogenase branch point. This study demonstrates the value of an integrated computational and experimental systems approach to exploring biological phenomena.
AFRIKAANSE OPSOMMING: In hierdie proefskrif word die gedrag en regulering van die sentrale koolstofmetabolisme in Escherichia coli K12 W3110 onder fermenterende mikro-a¨erobiese toestande ondersoek. Dit is moontlik gemaak deur ’n ge¨ıntegreerde stelsel-modelleringsbenadering, wat in Hoofstuk 1 bekendgestel word. D´ıe hoofstuk verskaf ook ’n oorsig van die metabolisme in E. coli. ’n Oopbron-kodepakket NMRPy, wat in die programmeringstaal Python ontwikkel is, word in Hoofstuk 2 beskryf. NMRPy verskaf ’n aantal funksies vir die basiese verwerking, analise en visualisering van Kern-Magnetiese Resonansie (KMR) spektroskopiese data, sowel as gespesialiseerde funksies vir die dekonvolusie van opeenvolgende reaksie-tydreekse. Hierdie funksionaliteit was onontbeerlik vir die verdere navorsing in hierdie proefskrif. Hoofstuk 3 beskryf die ontwikkeling van ’n nuwe metodiek vir die omvangryke bepaling van ensiem-kinetiese parameters vir sisteembiologie, deur van KMR gebruik te maak. In teenstelling tot tradisionele ensiem-kinetiese essai-metodes, is hierdie nuwe metodologie minder arbeidsintensief en lewer dit beduidend meer inligting per eksperiment. Deur die kinetiese vergelykings op tydsafhanklike KMR data te pas, word dinamiese veranderinge in substrate, produkte en allosteriese effektors gekwantifiseer en hierdie inligting gebruik in die passingsprosedure. Die data bevat inligting oor ko¨operatiewe substraatbinding, omkeerbaarheid, produkinhibisie en allosteriese effekte. Die voorgestelde metodologie word toegepas op die karakterisering van die eerste twee glikolitiese ensieme. In Hoofstuk 4 word die konstruksie, parameterisering en validering van ’n aantal kinetiese modelle van glikolise in E. coli onder mikro-a¨erobiese toestande uiteengesit. Die waarde van die modelleringsbenadering lˆe in die gemak waarmee omslagtige in vivo eksperimente in silico uitgevoer kan word. Om die onderste helfte van die glikolitiese pad te modelleer word ’n soortgelyke tegniek as in Hoofstuk 3 gebruik. Modelle van die reaksies vanaf triosefosfaat-isomerase tot by pirovaat-kinase is geparameteriseer deur dit op ’n versameling 31P KMR-tydreekse te pas. Hierdie benadering brei bostaande metodologie uit tot ensiem-subnetwerke en genereer data wat die volle kompleksiteit van regulerende interaksies in die netwerk insluit. Die geverifieerde modelle word in Hoofstuk 5 noukeurig ondersoek. ’n Strukturele analise van die modeltopologie word onderneem om die elementˆere fluksie-modes van fermentatiewe glikolise in E. coli te verklaar, sowel as om ’n futiele siklus rondom fosfo¨enolpirovaat karboksilase en fosfo¨enolpirovaat karboksikinase te identifiseer. Die bestendige-toestandsgedrag en kontrole-eienskappe word in silico ondersoek onder toestande van verskeie ATP beladings en suurstofbeskikbaarheid. ’n Aantal hipoteses word voorgelˆe, wat die regulering van vry energie in E. coli, sowel as die metaboliese reaksies van E. coli onder veranderende redoks-vereistes kan verklaar. Onder andere dui die resultate daarop dat die fosfo¨enolpirovaat:fosfotransferase sisteem (wat verantwoordelik is vir glukose-opname in die sel) die glikolitiese fluksie beheer en dat E. coli onder mikro-a¨erobiese toestande die redoksbalans nie net tussen asetaat en etanol kan reguleer nie, maar ook die deur wysiging van die fluksie-balans tussen asetaat en laktaat rondom die pirovaat-formiaat-liase/laktaatdehidrogenase vertakkingspunt. Hierdie studie toon die waarde van ’n ge¨ıntegreerde rekenaarmatige en eksperimentele sisteembenadering om biologiese verskynsels te ondersoek.
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Bawazir, Nada Sami. "Tuning of Plasma Membrane PI(4,5)P2 Charge Regulates Cell Migration and Glycolysis." Thesis, University of the Sciences in Philadelphia, 2020. http://pqdtopen.proquest.com/#viewpdf?dispub=27666361.
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Directional cell migration, chemotaxis, requires a polarized cell morphology in which the cell extends pseudopodia at the front and contracts the rear to move towards a stimulus. PI(4,5)P2 levels set up a threshold for the activity of signaling molecules at the rear and the leading-edge of a cell. To further demonstrate the importance of plasma membrane (PM) PI(4,5)P2 in maintaining cell morphology during chemotaxis, we used a mutant strain of the eukaryotic model system, Dictyostelium discoideum. This mutant strain lacks the type I PIP5 kinase, which is the main enzyme synthesizing PI(4,5)P2. These cells, designated pikI-, have highly reduced PI(4,5)P2 levels and higher Ras GTPase activity compared to wildtype cells. Leading-edge biosensors diffuse to the cytosol when the pikI- round-up and translocate back to the PM when the cells spread. These observations propose that PI(4,5)P2 levels elevate as cells round-up and decrease as cells spread. This interesting phenotype resembles the front and rear of a migratory cells. Interestingly, pikI- resemble similar cell morphology and biosensors dynamics observed when we use an inducible system to deplete PM PI(4,5)P2 levels. We, also, observed the dynamics of a biosensor for an F-actin polymerization protein called formin A (ForA). ForA has been shown to localize at a polarized cell’s rear and in the cleavage furrow of dividing cells. In addition, ForA have a PI(4,5)P2 binding motif and binds to PI(4,5)P2 preferentially in vitro. Our results support a role for PI(4,5)P2 in regulating ForA with the plasma membrane. Taken together, we proposed that local levels of PI(4,5)P2 contribute to the electrostatic interactions of regulatory proteins controlling actin dynamics and membrane protrusions. PM PI(4,5)P2 below a threshold activate regulatory proteins that excite the signaling that promotes protrusions, while below threshold levels would inhibit those proteins activity. The change in PI(4,5)P2 levels would be predicted to affect the membrane’s charge, which in turn changes the interaction and disassociation of many anionic regulatory proteins involved in the signaling pathway and cytoskeletal rearrangements. Additionally, we show for the first time, a correlation between the PM PI(4,5)P2 threshold and rates of phosphatidylserine (PS) exposure in cancer therapeutics. Receptor-mediated cell stimulation triggers PS exposure to the outer leaflet of the plasma membrane. Interestingly, pik1- and cells using an inducible system to deplete PM PI(4,5)P2 levels depicted the same responses. In addition to PI(4,5)P2, PS exposure affects the membrane’s charge which impacts the signaling molecules activity in the pathway. Altogether, PI(4,5)P2 and PS are proposed to be novel therapeutic targets in cancer treatments. Chemotaxis is a feature of metastatic cancer cells and is regulated by various regulators including actin cytoskeleton. Actin cytoskeleton reorganization during chemotaxis is regulated by actin-binding proteins including those that interact with the PM PI(4,5)P2. Energy production regulates cell migration as well, through glycolysis pathway. A previous study proposed that actin reorganization releases Aldo A enzyme which enters glycolysis, through activating PI3K signaling pathway. However, the mechanism of action remains unclear. We speculate that local PI(4,5)P2 levels regulate Aldo Activity through regulating actin-severing proteins activity including cofilin and gelsolin, and actin polymerizing protein including ForA. PI(4,5)P2 levels below a threshold release actin-severing proteins to the cytosol triggering the severing of actin and the release of Aldo A. while, above PI(4,5)P2 threshold activates and localizes for a on the PM promoting the F-actin polymerization and the sequester of Aldo A into F-actin. The goal of this work is to discover a new model for actin cytoskeleton regulation during migration, as its linkage to glycolysis and metabolism has important implications for cancer.
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Vettraino, Marina Eleonora <1983>. "The inhibition of aerobic glycolysis as a therapeutic approach to improve cancer chemotherapy." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6195/1/Vettraino_Marina_Eleonora_tesi.pdf.
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The aim of the research project discussed in this thesis was to study the inhibition of aerobic glycolysis, that is the metabolic pathway exploited by cancer cells for the ATP generation. This observation has led to the evaluation of glycolytic inhibitors as potential anticancer agents. Lactate dehydrogenase (LDH) is the only enzyme whose inhibition should allow a blocking of aerobic glycolysis of tumor cells without damaging the normal cells which, in conditions of normal functional activity and sufficient oxygen supply, do not need this enzyme. In preliminar experiments we demonstrated that oxamic acid and tartronic acid, two LDH competitive inhibitors, impaired aerobic glycolysis and replication of cells from human hepatocellular carcinoma. Therefore, we proposed that the depletion of ATP levels in neoplastic cells, could improved the chemotherapeutic index of associated anticancer drugs; in particular, it was studied the association of oxamic acid and multi-targeted kinase inhibitors. A synergistic effect in combination with sorafenib was observed, and we demonstrated that this was related to the capacity of sorafenib to hinder the oxidative phosphorylation, so that cells were more dependent to aerobic glycolysis. These results linked to LDH blockage encouraged us to search for LDH inhibitors more powerful than oxamic acid; thus, in collaboration with the Department of Pharmaceutical Sciences of Bologna University we identified a new molecule, galloflavin, able to inhibit both A and B isoforms of LDH enzyme. The effects of galloflavin were studied on different human cancer cell lines (hepatocellular carcinoma, breast cancer, Burkitt’s lymphoma). Although exhibiting different power on the tested cell lines, galloflavin was constantly found to inhibit lactate and ATP production and to induce cell death, mainly in the form of apoptosis. Finally, as LDH-A is able to bind single stranded DNA, thus stimulating cell transcription, galloflavin effects were also studied on this other LDH function.
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Vettraino, Marina Eleonora <1983>. "The inhibition of aerobic glycolysis as a therapeutic approach to improve cancer chemotherapy." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6195/.
Full textAbstract:
The aim of the research project discussed in this thesis was to study the inhibition of aerobic glycolysis, that is the metabolic pathway exploited by cancer cells for the ATP generation. This observation has led to the evaluation of glycolytic inhibitors as potential anticancer agents. Lactate dehydrogenase (LDH) is the only enzyme whose inhibition should allow a blocking of aerobic glycolysis of tumor cells without damaging the normal cells which, in conditions of normal functional activity and sufficient oxygen supply, do not need this enzyme. In preliminar experiments we demonstrated that oxamic acid and tartronic acid, two LDH competitive inhibitors, impaired aerobic glycolysis and replication of cells from human hepatocellular carcinoma. Therefore, we proposed that the depletion of ATP levels in neoplastic cells, could improved the chemotherapeutic index of associated anticancer drugs; in particular, it was studied the association of oxamic acid and multi-targeted kinase inhibitors. A synergistic effect in combination with sorafenib was observed, and we demonstrated that this was related to the capacity of sorafenib to hinder the oxidative phosphorylation, so that cells were more dependent to aerobic glycolysis. These results linked to LDH blockage encouraged us to search for LDH inhibitors more powerful than oxamic acid; thus, in collaboration with the Department of Pharmaceutical Sciences of Bologna University we identified a new molecule, galloflavin, able to inhibit both A and B isoforms of LDH enzyme. The effects of galloflavin were studied on different human cancer cell lines (hepatocellular carcinoma, breast cancer, Burkitt’s lymphoma). Although exhibiting different power on the tested cell lines, galloflavin was constantly found to inhibit lactate and ATP production and to induce cell death, mainly in the form of apoptosis. Finally, as LDH-A is able to bind single stranded DNA, thus stimulating cell transcription, galloflavin effects were also studied on this other LDH function.
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Pegoraro, Caterina. "Finding novel Neural Crest regulators : Pfkfb4, a key glycolysis partner, controls Neural Crest early patterning in Xenopus laevis." Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112374.
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La crête neurale (CN) est une population transitoire de cellules multipotentes qui émerge à la frontière entre l’ectoderme neural et non-neural, dans une région appelée la bordure neurale (BN). Lorsque la BN se soulève pour former le tube neural, les cellules de la CN subissent une transition épithélium-mésenchyme (TEM), et migrent de façon intensive dans l’ensemble de l’embryon pour atteindre leur destination finale et se différencier. Elles sont à l’origine de nombreux types de dérivés : neurones, cellules gliales, cartilage de la tête, os et tissus connectifs, cellules pigmentaires, cellules sympatho-adrenales. Tous ces processus sont régulés par l’action coordonnée de nombreux gènes qui forment un réseau de régulations génétiques complexe, au sein duquel de nombreuses interactions ont été décrites, même si de nombreuses relations restent à élucider à ce jour. Une mauvaise régulation de gènes normalement impliqués dans la formation de la CN provoque des malformations congénitales appelées neurocristopathies. Par ailleurs, la TEM subie par les cellules de CN avant leur migration est également observée dans les cellules cancéreuses acquérant des propriétés métastatiques. Les événements moléculaires et de nombreux gènes impliqués dans la TEM sont communs au développement de la CN et au cancer.Les liens existant entre le développement de la CN et les neurocristopathies, ainsi que les métastases, soulignent l’importance de l’étude du réseau de régulations génétiques permettant la formation de la CN et l’EMT.Au laboratoire, nous nous intéressons aux événements précoces d’induction et de spécification de la CN. Dans le but d’identifier les gènes préférentiellement impliqués dans le développement précoce de la CN et non dans la formation de l’ectoderme neural et non-neural, un crible a été effectué sur le transcriptome de différents tissus embryonnaires micro-disséqués. La validation des résultats de ce crible a permis d’identifier plusieurs gènes intéressants possédant une fonction potentielle dans la formation de la CN. Nous nous sommes particulièrement intéressés à deux d’entre eux, en raison de leur fonction originale comparée à la majorité des gènes impliqués dans le développement de la CN : serca1 et pfkfb4, un régulateur de l’homéostasie calcique et un régulateur de la glycolyse respectivement.Nous avons analysé les patrons d’expression des gènes des familles serca et pfkfb au cours du développement de Xenopus laevis. En raison de son expression spécifique dans la CN, nous avons étudié plus en détails le rôle de pfkfb4 dans la formation de la CN. Cette analyse a montré que pfkfb4 est nécessaire pour la spécification neurale et de la crête neurale.Toutefois, malgré son rôle documenté dans la glycolyse, le phénotype des morphants pfkfb4 dans l’embryon de Xenopus laevis n’est pas dû à une altération de la glycolyse.En conclusion, nos résultats démontrent l’existence d’un nouveau rôle non glycolytique pour Pfkfb4 au cours du développement embryonnaire de Xenopus LaevisNeural Crest (NC) is a transient population of multipotent cells that arises at the border between neural and non-neural ectoderm, in a region named the neural border (NB). As the neural border elevates to form the neural tube, NC cells undergo an Epithelial-To-Mesenchymal Transition (EMT), migrate extensively into the whole body to reach their final destinations and differentiate. They give rise to multiple derivatives: neurons and glia, head cartilage, bones and connective tissue, pigment cells, sympatho-adrenal cells. All these processes are regulated by the concerted actions of several genes that form a complex Gene Regulatory Network (GRN), in which many interactions have been elucidated, but even more relationships still need to be understood. Misregulation of genes normally involved in NC formation causes birth defects called neurocristopathies. Moreover, the EMT that NC cells undergo before migration also takes place when cancer cells become metastatic: the molecular events and many of the genes involved in EMT and migration are shared between NC development and cancer. The links with metastasis, neurocristopathies and the fact that still little is known about the earliest steps of NC formation, highlight the importance and the interest in understanding the Gene Regulatory Network (GRN) leading to NC formation and EMT.In the laboratory, we are interested in the early steps of NC induction and specification. In order to identify genes preferentially involved in early NC development compared to genes involved in neural and non-neural ectoderm formation, a transcriptome screen on different microdissected embryonic tissues has been performed. The validation of the results of the screen revealed several interesting genes with a potential function in NC formation. We focused particularly on two of them, due to their original function compared to the majority of the genes involved in NC development: serca1 and pfkfb4, a calcium homeostasis regulator and a glycolysis regulator respectively. We analysed the expression patterns of serca and pfkfb family genes during Xenopus laevis development. Then, due to its specific expression in NC, we studied more in details the role of pfkfb4 in NC formation. This analysis revealed that pfkfb4 is necessary for neural and neural crest specification. However, despite its known role in glycolysis, pfkfb4 morphant phenotype in Xenopus laevis embryos is not due to an alteration of the glycolytic pathway.In conclusion, our results reveal a novel extra-glycolytic role for Pfkfb4 during Xenopus laevis embryonic development
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Ellingson, William J. "The effects of 3-phosphoglycerate and other metabolites on the activation of AMP-activated protein kinase by LKB1/STRAD/MO25 /." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1406.pdf.
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Baker, Jennifer Mary. "The effect of extracellular pH on human platelet metabolism." Thesis, University of Birmingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368422.
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Quinn, Gregory Bernard. "The recombinant expression and characterization of human neuron specific enolase." Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241344.
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Crowther, Gregory John. "An analysis of metabolic fluxes in contracting human skeletal muscle /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/10538.
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Poulain, Laury. "Etude du métabolisme du glucose dans les leucémies aigües myéloïdes et implication de la voie de signalisation mTORC1." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCB028/document.
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Les Leucémies Aigües Myéloïdes (LAM) sont des hémopathies malignes hétérogènes de mauvais pronostic qui se caractérisent par une expansion clonale de progéniteurs immatures. De nombreuses dérégulations de voies de signalisation sont retrouvées dans les cellules leucémiques et leur confèrent un avantage de prolifération et de survie. La voie de signalisation mTORC1, qui contrôle la traduction protéique, l’autophagie et plusieurs voies métaboliques, est ainsi constitutivement activée dans les cellules leucémiques. La reprogrammation métabolique notamment via « l’effet Warburg » est un phénomène bien décrit dans les cellules cancéreuses. L’augmentation de l’utilisation de la glycolyse, confère aux cellules tumorales un avantage de survie en favorisant une production rapide d’ATP et d’intermédiaires métaboliques nécessaires pour les biosynthèses de nucléotides, d’acides-aminés et de lipides. C’est donc dans ce contexte que j’ai étudié le métabolisme du glucose dans les cellules de LAM et l’implication de la voie de signalisation mTORC1 dans la dérégulation de ce métabolisme. J’ai tout d’abord identifié par une étude transcriptomique dans la lignée leucémique MOLM-14 que la signalisation mTORC1 contrôle plusieurs voies métaboliques notamment celles permettant l’utilisation du glucose. Ceci a été vérifié dans plusieurs lignées de LAM puisque l’inhibition ou la sur-activation de mTORC1 entrainent respectivement une diminution ou une augmentation de la consommation de glucose et de la production de lactate. De façon intéressante, le niveau d’activation de la voie mTORC1 détermine la sensibilité des cellules leucémiques à l’inhibition de la glycolyse. En effet, lorsque mTORC1 est activé, le blocage de la glycolyse induit de l’autophagie et l’apoptose des cellules leucémiques. A l’inverse, le blocage de mTORC1 induit une reprogrammation métabolique des cellules leucémiques qui utilisent alors principalement la phosphorylation oxydative pour produire l’ATP dont elles ont besoin. Leur survie devient alors indépendante du glucose. A l’inverse des cellules primaires de LAM, les cellules hématopoïétiques immatures normales CD34+ sont moins sensibles au blocage de la glycolyse. Le ciblage du métabolisme du glucose pourrait donc constituer une stratégie thérapeutique intéressante dans les LAM. Je me suis ensuite intéressée aux effets anti-leucémiques induits par l’inhibition de la voie des pentoses phosphates (PP) et plus particulièrement au ciblage de la G6PD (glucose-6-phosphate déshydrogénase) par le composé le 6-aminonicotinamide (6-AN). En effet, une étude de flux métabolique a permis de mettre en évidence qu’une proportion importante de glucose est dirigé vers la voie des PP, laissant suggérer que l’addiction des cellules leucémiques au glucose pourrait être liée à une utilisation augmentée de cette voie annexe. J’ai alors observé que le 6-AN induit une cytotoxicité in-vitro y compris dans les cellules primaires de patients, sans avoir d’effets sur les cellules hématopoïétiques normales et in-vivo dans un modèle de xénogreffe de la lignée MOLM-14 chez la souris NUDE. Cette étude a donc permis de montrer que l’activation constitutive de mTORC1 rend la survie des cellules de LAM dépendante de la glycolyse et crée une sensibilité spécifique à l’inhibition de la G6PD. La dérégulation de la signalisation mTORC1 étant quasi-constante dans les LAM, cibler la G6PD pourrait donc représenter une stratégie thérapeutique intéressanteAcute Myeloid Leukemia (AML) are heterogeneous hematological diseases with poor prognosis characterized by a clonal expansion of immature progenitors. Many deregulation of signaling pathways are found in leukemic cells and give them an advantage of proliferation and survival. The MTORC1 signaling pathway, which controls protein translation, autophagy and several metabolic pathways, is constitutively activated in leukemic cells. Metabolic reprogramming in particular the "Warburg effect" is a phenomenon well described in cancer cells. High rate of glycolysis has been considered to give tumour cells advantages through rapid production of ATP and intermediates for the synthesis of nucleotides, amino acids, and lipids. In this context, I studied glucose metabolism in AML cells and the involvement of the mTORC1 signaling pathway in the deregulation of this metabolism. First, I identified by a transcriptomic analysis in the MOLM-14 cell line that mTORC1 signaling controls several metabolic pathways including those for glucose utilization. This has been verified in several AML cell lines, since inhibition or over-activation of mTORC1 respectively induces a decrease or an increase in glucose consumption and lactate production. Interestingly, the level of activation of the mTORC1 signaling pathway determines the sensitivity of AML cells to the inhibition of glycolysis. Indeed, when mTORC1 is activated, the blockade of glycolysis induces autophagy and apoptosis of leukemic cells. Conversely, blocking mTORC1 induces metabolic reprogramming of leukemic cells, which then mainly use oxidative phosphorylation to produce ATP for their needs. AML cell survival become independent of glucose. Unlike primary AML cells, survival of normal immature hematopoietic cells CD34+ is only barely affected by the blockade of glycolysis. Thus, targeting the glucose metabolism may constitute an attractive therapeutic strategy in AML. I then investigated the anti-leukemic activity induced by the inhibition of the pentose phosphate pathway (PPP) and more particularly by the specific blockade of G6PD (glucose 6-phosphate dehydrogenase) with the 6-aminonicotinamide (6- AN) compound. Indeed, a metabolic flux analysis demonstrated that a significant proportion of glucose was directed towards the PPP. This result suggested that the addiction of leukemic cells toward glucose might be related to an increased use of PPP. I then observed that the 6-AN induced in vitro cytotoxicity including in primary AML cells from patients without effect on normal immature hematopoietic cells CD34+ and in vivo in a xenograft model of MOLM-14 cell line in the NUDE mouse. This study therefore demonstrated that the constitutive activation of mTORC1 makes AML cells survival dependent on glycolysis, and creates a specific vulnerability to the inhibition of G6PD. Given that deregulation of the mTORC1 signaling pathway is almost constant in AML, targeting G6PD may therefore represent an interesting therapeutic strategy
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Ozawa, Shota. "Glycolysis, but not Mitochondria, responsible for intracellular ATP distribution in cortical area of podocytes." Kyoto University, 2017. http://hdl.handle.net/2433/217989.
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Campanelli, John R. (John Richard). "The kinetics of hydrolysis and glycolysis of poly(ethylene terephthalate) melts at high temperatures." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41312.
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The hydrolytic depolymerization of poly(ethylene terephthalate), or PET, in excess water was studied at high temperatures in a 2 L pressure reactor. At an initial water/PET loading (w/w) of 5.1 or greater, essentially complete depolymerization was obtained at 265$ sp circ$C. The yield of terephthalic acid monomer was 97% of the theoretical value. The yield of ethylene glycol monomer was lower, 91%, due in part to a dimerization side reaction.An end-group analysis method was developed involving the titration of carboxyl groups of hydrolysate samples dissolved in one of two solvent systems, dimethylphenol:chloroform or dimethylsulphoxide, depending on reaction extent.
A kinetic model was developed and found to provide a good fit with experimental data and with equilibrium concentrations. The activation energy of hydrolysis was calculated to be 56 kJ/mol. Zn$ sp{+2}$ catalysts increased the hydrolysis rate constant by about 20% at the same reaction temperature.
PET glycolysis was studied at the same conditions of temperature and initial reactor loading as for hydrolysis using a method based on the removal of unreacted ethylene glycol from the product mixture through careful drying. The activation energy of glycolysis was found to be 102 kJ/mol. Glycolysis rate constants were about 7 times greater than the corresponding hydrolysis rate constants. The difference between the sets of rate constants is attributed largely to the morphology of the respective reaction mixtures (solution/emulsion).
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Doyen, Jérôme. "Rôle des protéines de régulation du pH intracellulaire et du métabolisme énergétique dans les carcinomes du sein triple négatif." Electronic Thesis or Diss., Nice, 2013. http://www.theses.fr/2013NICE4147.
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Les cancers agressifs se caractérisent par un métabolisme glycolytique exacerbé avec surexpression de protéines assurant le contrôle du pH intracellulaire par l’export efficace des déchets métaboliques acides (par CAIX, CAXII, MCT1 et MCT4 entre autres). Les cancers du sein dit "triple négatif" (sans expression des récepteurs à l'estrogène, progestérone et Her-2) présentent une consommation augmentée de glucose et un plus mauvais pronostic en comparaison avec les autres cancers du sein. L'analyse immunohistochimique de l'expression des protéines glycolytiques d'une cohorte de 159 patientes TNEG a montré que MCT4 était prédictif de la survenue de métastases et de décès. Le ciblage in vitro de MCT4 par la technique des Zinc Finger Nucléases (ZFN) a eu un effet anti-prolifératif. L'efficacité était toutefois maximale lors du ciblage combiné de MCT1 (inhibiteur pharmacologique), MCT4 et de la respiration mitochondriale par la phenformine dans la lignée de cancer TNEG Hs578t. Cette étude montre donc que le ciblage des protéines glycolytiques pourrait être une piste intéressante dans le traitement des cancers du sein TNEG. Un autre travail a permis d'exploiter le ciblage des protéines glycolytiques, notamment CAIX et CAXII, pour augmenter in vitro et in vivo la radiosensibilité de lignées de cancer colorectal tout en démontrant un mécanisme original de radiosensibilisation, via l'acidification intracellulaire. Enfin, nous avons mis en évidence l'importance de l'hypoxamiR miR210 dans la radiorésistance de lignées de cancer du poumon, avec une radiorésistance semblant dépasser l'effet oxygèneAgressive cancers often harbor an exacerbated glycolytic metabolism with overexpression of proteins that maintain intracellular pH by extruding metabolic acid waste (via CAIX, CAXII, MCT1 and MCT4 among others). The "triple-negative" breast cancers (with no expression of estrogen, progesteron and Her-2 receptors) have an increased consumption of glucose and worse prognosis in comparison with other breast cancers. Immunohistochemical analysis of glycolytic proteins among 159 patients with TNEG breast cancer, showed that MCT4 was predictive for metastasis and death occurence. In vitro targeting of MCT4 by Zinc Finger Nuclease (ZFN) technique demonstrated an anti-proliferative effect. However, the maximal anti-proliferative effect was observed with the combination of MCT4/MCT1 (by pharmacological inhibition) and mitochondrial respiration by phenformine in the Hs578t TNEG cell line. This study demonstrated that targeting glycolytic protein could have a therapeutic effect in TNEG breast cancers. Another study also use targeting of glycolytic protein such as CAIX and CAXII to increase in vitro and in vivo radiosensitivity of colorectal cell lines while demonstrating an original mechanism of radiosensitization by increasing intracellular acidosis. Finally we demonstrated that the hypoxamiR miR210 was involved in the radioresistance of lung cancer cell line with a stronger impact than the oxygen effect
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Shao, Wei 1970. "Identification of caspase-1 and caspase-3 substrates and study on caspase-1 substrates in glycolytic pathway." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100248.
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Apoptosis is executed by caspase-mediated cleavage of various proteins. Elucidating the consequence of substrate cleavage provides us with insight into cell death and other biological processes. In this study, we applied the diagonal gel approach, a proteomic strategy, to identify substrates of the inflammatory caspase, caspase-1 and the cell death executioner caspase, caspase-3. Our results showed significant overlap between the substrates cleaved by both caspase-1 and -3. Such substrates are implicated in common cellular functions, including maintenance of the cytoskeleton, folding of proteins, translation, glycolysis, bioenergetics, signaling and trafficking. An important finding is that many glycolysis enzymes were targeted specifically by caspase-1. Processing of these glycolysis enzymes by caspase-1 was confirmed by cleaving in vitro transcribed and translated substrates with recombinant caspase-1. We have focused our further analysis on certain glycolysis enzymes. We have characterized the caspase-1 cleavage site in GAPDH. Point mutation of the Aspartic acid at position 189 to Alanine (D189A) in GAPDH blocked its cleavage by caspase-1. In vivo, in a mice model of septic shock, characterized by hyperactivation of caspase-1, we observed depletion of the full-length forms of these glycolysis enzymes in the diaphragm muscle. Further studies in caspase-1 deficient mice will confirm whether this depletion, in caspase-1 proficient mice, was due to caspase-1 processing of the glycolysis enzymes. This provides a direct link between caspase-1 activation and inhibition of glycolysis, which might have important implications on loss of muscle contractility in septic shock.
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Williams, Andrew C. "Glucose metabolism in human spermatozoa." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302101.
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Patterson, Bly Addison. "Pectoralis muscle of turkey displays divergent function as correlated with meat quality." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/52929.
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Fresh turkey meat color is influenced by a myriad of biological factors which include muscle fiber type composition and heme protein concentrations. These factors either contribute to or are subject to the biochemical events involved in the conversion of muscle to meat. Subtle deviations in the processing environment can also result in aberrant fresh meat quality development and may ultimately alter the quality characteristics of cooked product. Our objective was to describe the underlying cause and significance of two-toning in fresh turkey breast. In the first experiment, pectoralis muscles were collected and subjected to image processing software to describe color of fresh turkey. In the second experiment, shackling time was tested as an aggravator of fresh turkey color. Results showed turkey breast possess two-lobes that differ in pH, drip loss, energy metabolism and muscle fiber type composition. Results also showed fresh turkey color was enhanced during the time from stun to exsanguination (P < 0.05). These results suggest inherent differences in breast muscle are responsible for variations in fresh turkey color.Master of Science