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The project that will be discussed in these few lines is about the endocannabinoid system and more specifically about an enzym of that system, the monoacylglycerol lipase (MAGL).The endocannabinoid system is a signaling system composed of lipid mediators called endocannabinoid. A part from these endogenous ligands, this system comprises also the proteins for their synthesis, endocannabinoid transporters and the cannabinoid receptors. The endocannabinoid system could be a potential therapeutic target in pathologies like inflammation , pain, Joss of appetite in late stage cancer. ..One of the key enzymes is the monoacylglycerol lipase (MAGL). It is, with the fatty acid amine hydrolase (FAAH), the most important enzymes involved in the endocannabinoids inactivation. It makes it a great pharmacologie target to modulate the effect of the endocannabinoid system. Synthesizing specific inhibitors of the MAGL is one of the main challenges since it will help characterize the physiologie impact of that system. The aim of the project that will discuss in the next lines is to enable the application of rational drug design to synthetize selective and powerful inhibitors.The report presented here will treat the different steps that enabled, through techniques like protein engineering, the acquisition of multiple MAGL recombinan'ts. Crystallization of wild- type MAGL is often difficult, that's why recombinant enzymes were created in other to improve crystallization. lt will enable the production of better crystallographic images thanksto X-ray crystallography, and to raise their resolution. We hope that recombinant proteins will help to acquire new information on the enzyme and the enzyme-inhibitor/ligand complex.These informations will provide data in order to enable the use of rational drug design and will make the task of designing new selective and powerful inhibitors easier. Le projet qui sera exposé dans ces lignes traite du système endocannabinoïde et plus particulièrement d'une des enzymes de ce système la monoacylglycérol lipase (MAGL)Le système endocannabinoïde est un système de signalisation complexe composé de transmetteurs de nature lipidique appelés endocannabinoïdes. Le système est également composé des protéines de synthèses, dégradations et transports des endocannabinoïdes ainsi que de leurs récepteurs. Le système endocannabinoïde pourrait avoir certaines potentialités thérapeutiques notamment dans le domaine de l'inflammation, de la nociception ou dans le domaine de la gestion de la prise alimentair. Une des enzymes clé du systèe est la monoacylglycérol lipase (MAGL). Elle constitue avec lafatty acid amine hydrolase (FAAH), le principal couple d'enzymes impliquée dans la dégradation des endocannabinoïdes et de ce fait constitue une cible pharmacologique intéressante qui permettrait de moduler finement la transmission de ce système. L'élaboration d'inhibiteurs spécifiques de la MAGL est actuellement un enjeu majeur dans l'étude du système endocannabinoïde. Le projet qui sera ici exposé s'inscrit dans ce domaine avec comme objectif final de permettre l'application des techniques dites de rational drug design, à la recherche de nouveaux inhibiteurs affins et sélectifs. Le mémoire ici présenté, traitera donc des différentes étapes qui permirent l'obtention, via diverses techniques de protein engineering, de plusieurs MAGL recombinantes. La cristallisation de la MAGL sauvage étant particulièrement ardue, ces MAGL recombinantes ont été créées dans l'optique de permettre une cristallisation plus aisée de la protéine. Ces proteines faciliterait l'obtention d'images en cristallographie à rayon X tout en augmentant la résolution des ces dernières. Nous espérons qu'à terme, ces protéines mutantes permettront de faciliter l'obtention d'informations sur l'enzyme ainsi que sur les potentiels complexes avec divers inhibiteurs/ligands. Ces informations ouvriraient la voie au processus de rational drug design permettant ainsi le design de nouveaux inhibiteurs spécifiques et affins.
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Enzymology --- Lipase --- Biotechnology --- Enzymes --- Lipases
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2-Arachidonoylglycerol (2-AG) is one of the main mediators of the endocannabinoid system.Considering its physiological properties, it would be interesting to increase its endogenous levels by inhibiting its catabolism, which is mainly mediated by monoacylglycerol lipas(MGL).Therefore, the aim of this work was to assess the in vivo potential of disulfiram (DSF), a MG L inhibitor characterized in vitro, to increase 2-AG levels in miceFirstly, we established in the laboratory a HPLC-MS method to quantify 2-AG levels, in order to evaluate the effect of our pharmacological treatments. Secondly, we studied DSF potential to inhibit MGL by carrying out two types of assays: (i) in vitro assays on neuroblastoma cells in culture and (ii) in vivo administration to mice.ln conclusion, our studies did not show an increase in 2-AG levels following DSF administration in none of the structures of the central nervous system. This is in contrast with the increase observed following the administration of JZL 184, a reference MGL inhibitor.Nevertheless.The methods and protocols developed during this study will enable the investigation of other potential MGL inhibitors or even, at a larger scale, will enable studies of other bioactive lipids linked to the endocannabinoid system. Le 2-arachidonoylglycérol (2-AG) est l'un des médiateurs pnnc1paux du système endocannabinoïdes. Au vu de ses propriétés physiologiques, il serait intéressant de pouvoir en augmenter les taux endogènes notamment en inhibant son catabolisme, principalement médié par la monoacylglycérol lipase (MGL). L'objectif de ce travail a donc été d'évaluer le potentiel in vivo d’un inhibiteur de cette enzyme, déjà décrit pour ses propriétés in vitro, à savoir le disulfirame (DSF).Dans cette optique, nous avons premièrement établi au laboratoire une méthode HPLC MS permettant de doser le 2-AG, et donc d'évaluer le résultat de nos essais pharmacologiques. Nous avons ensuite étudié le caractère inhibiteur du DSF sur la MGL en menant deux types d'essais : (i) essais in vitro sur des neuroblastomes en culture et (ii) administration in vivo à des souns. En conclusion, nos études n'ont pu démontrer une augmentation significative des taux de 2-AG dans diverses structures du système nerveux central suite à l'administration de DS, contrairement à l 'augmentation que nous avons observée avec un inhibiteur de référence, le JZL 184. Néanmoins, les méthodes et protocoles mis au point au cours de ce travail permettront l'investigation d'autres inhibiteurs potentiels de la MGL ou même, dans un cadre plus global, rendraient possible l'étude d'autres lipides bioactif liés au système endocannabinoïdes.
Disulfiram --- Monoacylglycerol Lipases --- 2-arachidonylglycerol
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Enzymes --- Biotechnology --- Biomedical engineering --- Antibodies --- Catalysis --- Lipases --- Micelles --- Reaction mechanism
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Endocannabinoid system is characterized by its main receptors the CB1 and CB2 receptors and by their natural ligands, the encocannabinoids, the main ones being the anandamine (AEA) and the 2-arachidonoylglycerol (2-AG). These are the actors of the control of different physiological functions like pain and inflammation, appetite stimulation, vomiting, anxiety or immune defenses. Endocannabinoids are quickly hydrolysed by enzymes, the Fatty Acid Amide Hydrolase 5FAAH) and the Monoacylglycerol Lipase (MAGL). The aim of this work is to search for inhibitors of these enzymes in order to prolong the beneficial effects of endocannabinoïdes. Compounds belonging to the family of 4H-3,1-benzoxazin-4-ones or a derivative family, the 4H-3,1-benzothiazin-4-one, have been synthesized and characterized. Their inhibitory potential toward the two enzyme has them been tested. The 4H-3,1-benzoxazine-4-ones seem interesting in respect of MAGL or FAAH inhibition, depending on the fact that their lateral moiety in position 2 is bound by an oxygen or a carbon atom respectively. On the other side, 4H-3,1-benzoxazin-4-ones don’t present any inhibitory activity toward those two enzymes Le système endocannabinoïde est caractérisé par ses récepteurs principaux que sont les récepteurs CB1 et CB2 et par leurs ligands naturels, les endocannabinoïdes, dont les principaux sont l’anandamide (AEA) et le 2-arachidonoylglycérol (2-AG). C’est par ces acteurs que peut s’opérer un contrôle de diverses fonctions de l’organisme telles que la douleur et l’inflammation, la stimulation de l’appétit, les vomissements, l’anxiété ou encore les défenses immunitaire. Les endocannabinoïdes sont rapidement dégradés par des enzymes hydrolytiques, la Fatty Acid Amide Hydrolase (FAAH) et la Monoacylglycérol Lipase (MAGL). Le but de ce travail est de chercher des inhibiteurs de ces enzymes afin de pouvoir prolonger les effets bénéfiques des endocannabinoïdes. Des composés faisant partie de la famille des 4H-3,1-benzoxazin-4-ones ou d’une famille dérivée, les 4H-3,1-benzothiazin-4-one ont été synthétisés et caractérisés. Leur potentiel inhibiteur sur ces deux enzymes a ensuite été évalué. Les 4H-3,1-benzeoxazin-4-ones semblent présenter un intérêt dans l’inhibition de la MAGL ou de la FAAH selon que leur chaîne latérale en position 2 est liée par un atome d’oxygène ou de carbone respectivement. Par contre, les 4H-3,1-benzoxazin-4-ones semblent dénués d’une activité inhibitrice sur ces enzymes
Endocannabinoids --- anandamide --- fatty acid amide hydrolase 2, human --- Monoacylglycerol Lipases
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Biological techniques --- Enzymology --- Human biochemistry --- Lipoprotéines plasmatiques. --- Plasma. Lipoproteïnen. --- Plasma. Lipoproteinen. --- Blood lipoproteins --- Lipoproteins --- Lipoprotéines --- Lipoprotéines plasmatiques --- Apolipoprotéines --- Lipases --- Lipoproteins, apo
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This volume contains eight chapters that present both new and reviewed information fundamental to a clear understanding of lipid catabolism and transport at the molecular level. Three-dimensional structures of important serum lipoproteins, apolipoproteins, and lipases, utilizing X-ray data when available, are emphasized, and an attempt is made to relate structures to function.Key Features* Amphipathic helix* Apolipoprotein E* Lipophorin* Structure of serum albumin* Lipid binding proteins* Apolipoprotein B* Low-density lipoprotein
577.125 --- 577.115 --- 577.115 Lipids. Lipoids. Fats. Fat-like substances --- Lipids. Lipoids. Fats. Fat-like substances --- 577.125 Lipid metabolism. Lipoid metabolism. Fatty-acid metabolism --- Lipid metabolism. Lipoid metabolism. Fatty-acid metabolism --- Lipases --- Lipoproteins --- Lipoproteins, apo --- Proteins. --- Lipoproteins.
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This book presents the state of the art in the synthesis very complex saccharide structures, written by leading scientists at the forefront of this rapidly growing field. Reflecting the particular significance in recent years of efficient and selective procedures employing enzymes for preparative purposes in the carbohydrate field, a major proportion of the articles focus on these biocatalytic methods. In addition, recent strategies for the construction of unusual carbohydrates structures employing novel and creative methodologies are highlighted. Further, particular emphasis is placed on very complex saccharide structures as well as on special solutions to problems that are particularly challenging.
Carbohydrates --- Oligosaccharides --- Glycoconjugates --- Glycoconjugués --- Synthesis. --- Synthèse. --- Chemistry. --- Organic chemistry. --- Biochemistry. --- Organic Chemistry. --- Biochemistry, general. --- Glycoconjugués --- Synthèse. --- Biological chemistry --- Chemical composition of organisms --- Organisms --- Physiological chemistry --- Biology --- Chemistry --- Medical sciences --- Organic chemistry --- Composition --- Carbohydrates - Synthesis. --- Oligosaccharides - Synthesis. --- Glycoconjugates - Synthesis. --- OLIGOSACCHARIDES --- OLIGOSACCHARIDES, CONJUGATES --- GLYCOSIDE HYDROLASES --- LIPASES --- SIALIC ACIDS --- GLYCOSYLATION --- GLYCOPEPTIDES --- ERGOT ALKALOIDS --- PREPARATION
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Natural products have been a source of inspiration for chemists and chemical biologists for many years, and have a special relevance in the chemical space. In recent years, several novel synthetic strategies have appeared, such as diversity-oriented synthesis (DOS), biological-oriented synthesis (BiOS), and function-oriented synthesis (FOS), for accessing complex and functionally diverse molecules. In this manner, the synthesis of natural products has evolved towards simpler and ecological methods using biotransformation, combinatorial chemistry, or organocatalysts. In this issue, Prof. Chojnacka shows demonstrates the use of immobilized lipases as catalysts to aid in the synthesis of phosphatidylcholine enriched with myristic acid. Profs. Vila and Pedro used catalysts derived from (S)-mandelic acid to achieve the catalytic enantioselective addition of dimethylzinc to isatins. Prof. Diez shows the possibility of the obtention of 7,8-carvone epoxides in a diastereoselective manner using proline, quinidine, and diphenylprolinol as organocatalysts. A cheap, simple, clean, and scalable method involves the use of deep eutectic mixtures as reaction media, and Profs. Alonso and Guillena describe the use of this methodology for the enantioselective, organocatalyzed ?-amination of 1,3-dicarbonyl compounds. Biotransformations have been one of the methodologies for more efficient synthesis of natural products. Prof. Wu transforms ergostane triterpenoid antcin K using Psychrobacillus sp. Ak 187. Finally, Prof. Kovayashi reviews the total synthesis and biological evaluation of phaeosphaerides. The reader, through this issue, could gain an idea of the new directions that the synthesis of natural products using catalysts will have in the years to come.
n/a --- structured phosphatidylcholine --- carvone --- immobilized lipases --- trimyristin --- 3-hydroxyoxindole --- green chemistry --- structural revision --- anticancer --- triterpenoid --- organocatalysis --- natural products --- epoxidation --- ?-amination --- benzimidazole --- total synthesis --- zinc --- Antrodia cinnamomea --- aminocatalysis --- epoxide --- asymmetric organocatalysis --- mandelamides --- STAT3 --- asymmetric catalysis --- Psychrobacillus --- isatin --- chiral ?-hydroxyamide --- interesterification --- proline --- phaeosphaeride B --- biotransformation --- phaeosphaeride A --- myristic acid --- egg-yolk phosphatidylcholine --- acidolysis --- antcin K --- deep eutectic solvents
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During the last few decades, environmental concerns have prompted the food industry to find sustainable solutions in terms of the efficient use of natural resources and the development of eco-friendly processes and products, following the principles of a circular economy and biorefinery concepts. In the field of edible oil processing in particular, novel technologies have been developed to avoid the use of highly pollutant organic solvents and chemicals, high temperatures, and chemical catalysts as well as to produce novel lipids with improved functional and bioactive properties. In these novel products, the use of either traditional or non-traditional lipid sources from agro-wastes or by-product origins have been explored. These strategies meet consumers’ concerns about what they eat and about the impact of their diet on their health and wellness. Therefore, this Special Issue comprises a collection of innovative research articles and review papers on advances in edible oil processing, including the following topics of interest: (1) Enzyme-catalyzed processes; (2) Emerging physical extraction techniques; (3) Green solvent extractions; (4) Innovative processes in olive oil extraction technology; (5) Contaminant mitigation technology; (6) Novel products.
solid-phase microextraction-arrow --- multiple headspace solid-phase microextraction --- pyrazine --- flavor edible oil --- internal standard method --- emulsion --- oxidative stability --- microbiological criteria --- phenolic compounds --- physicochemical characteristics --- co-extraction --- flavored oil --- response surface methodology --- phenols --- thyme --- Argania spinosa oil --- capric acid --- caprylic acid --- commercial immobilized lipases --- low-calorie structured lipids --- vegetable oils --- phospholipase --- enzymatic degumming --- phospholipids --- human milk --- human milk fat substitutes --- structured lipids --- infant formula
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