subject:(constitutive androstane receptor)

1. Barretto, Sharon Ann. Etude des interactions bidirectionnelles entre le microbiote intestinal et les récepteurs aux xénobiotiques CAR et PXR : Insights into the bidirectional interactions between the gut microbiota and the xenobiotic receptors CAR and PXR.

Degree: Docteur es, Maladies métaboliques et cardiovasculaires, 2019, Université Toulouse III – Paul Sabatier

URL: http://www.theses.fr/2019TOU30233

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Le pregnane X receptor (PXR, NR1I2) et le récepteur constitutif aux androstanes (CAR, NR1I3) sont deux récepteurs nucléaires hépatiques et intestinaux qui régulent la transcription… (more)

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Le pregnane X receptor (PXR, NR1I2) et le récepteur constitutif aux androstanes (CAR, NR1I3) sont deux récepteurs nucléaires hépatiques et intestinaux qui régulent la transcription d'enzymes de détoxification des xénobiotiques. Des travaux antérieurs ont montré que l'expression des gènes cibles de CAR et PXR est significativement réduite dans le foie des souris axéniques. Dans ce projet de thèse, nous avions pour objectif de mieux comprendre les interactions bidirectionnelles entre le microbiote intestinal et ces xénosenseurs. Nous avons d'abord utilisé une approche pharmacologique chez les souris mâles WT vs Pxr-/- et comparé la signature transcriptomique des gènes régulés par PXR dans le foie lors de l'activation via le PCN. L'activation de PXR a augmenté l'accumulation de triglycérides hépatiques. Nous avons observé un chevauchement significatif entre les gènes régulés négativement lors de l'activation de PXR et une liste de gènes cibles de PPARδ induits par le jeûne. Parmi ceux-ci, nous avons identifié le facteur de croissance de fibroblastes 21 (Fgf21) comme un nouveau gène régulé par PXR. L'activation de PXR a aboli les taux plasmatiques de FGF21. Ces premiers résultats ont fourni une signature complète de l'activation de PXR dans le foie et ont identifié de nouveaux gènes cibles potentiellement impliqués dans les effets stéatogènes et pléiotropes de PXR. Ensuite, nous avons comparé la signature hépatique à la signature intestinale de l'activation pharmacologique de PXR, ce qui nous a permis d'identifier les gènes cibles communs de PXR dans ces 2 organes. Enfin, nous avons utilisé des souris Pxr+/+ et Pxr-/- littermate et supprimé le microbiote intestinal au moyen d'antibiotiques (ATB). En utilisant les gènes cibles de PXR identifiés précédemment, nous avons confirmé que les ATB réduisaient de manière significative l'activité de PXR dans le foie et l'iléon. Des analyses transcriptomiques hépatiques ont montré que les ATB diminuaient un nombre beaucoup plus élevé de gènes PXR-dépendants dans le foie des souris mâles que chez les femelles. Chez les mâles, l'axe microbiote intestinal-PXR contrôlait le métabolisme des xénobiotiques et le remodelage des lipides hépatiques. À l'inverse, le séquençage 16S et la métabolomique par RMN du contenu caecal ont révélé des différences subtiles mais significatives dans la composition du microbiote intestinal des souris Pxr-/- par rapport aux souris Pxr+/+, uniquement chez les mâles. Nos résultats démontrent donc que, dans le foie, PXR est un senseur majeur du microbiote intestinal qui contrôle les capacités de détoxication de l'hôte et le métabolisme des lipides de manière sexuellement dimorphique. [...]

The pregnane X receptor (PXR, NR1I2) and the constitutive androstane receptor (CAR, NR1I3) are two liver and intestine-enriched nuclear receptors that act as transcriptional regulators of enzymes critical for the detoxification of xenobiotics and endogenous metabolites. Previous works have shown that the expression of CAR and PXR target genes is significantly reduced in the…

Advisors/Committee Members: Payrastre, Laurence (thesis director), Ellero, Sandrine (thesis director).

Subjects/Keywords: Antibiotiques; Xénobiotiques; Microbiote intestinal; Constitutive androstane receptor; Pregnane X receptor; Antibiotics; Xenobiotics; Gut microbiota; Constitutive androstane receptor; Pregnane X receptor

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Barretto, S. A. (2019). Etude des interactions bidirectionnelles entre le microbiote intestinal et les récepteurs aux xénobiotiques CAR et PXR : Insights into the bidirectional interactions between the gut microbiota and the xenobiotic receptors CAR and PXR. (Doctoral Dissertation). Université Toulouse III – Paul Sabatier. Retrieved from http://www.theses.fr/2019TOU30233

Chicago Manual of Style (16^th Edition):

Barretto, Sharon Ann. “Etude des interactions bidirectionnelles entre le microbiote intestinal et les récepteurs aux xénobiotiques CAR et PXR : Insights into the bidirectional interactions between the gut microbiota and the xenobiotic receptors CAR and PXR.” 2019. Doctoral Dissertation, Université Toulouse III – Paul Sabatier. Accessed March 04, 2021. http://www.theses.fr/2019TOU30233.

MLA Handbook (7^th Edition):

Barretto, Sharon Ann. “Etude des interactions bidirectionnelles entre le microbiote intestinal et les récepteurs aux xénobiotiques CAR et PXR : Insights into the bidirectional interactions between the gut microbiota and the xenobiotic receptors CAR and PXR.” 2019. Web. 04 Mar 2021.

Vancouver:

Barretto SA. Etude des interactions bidirectionnelles entre le microbiote intestinal et les récepteurs aux xénobiotiques CAR et PXR : Insights into the bidirectional interactions between the gut microbiota and the xenobiotic receptors CAR and PXR. [Internet] [Doctoral dissertation]. Université Toulouse III – Paul Sabatier; 2019. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2019TOU30233.

Council of Science Editors:

Barretto SA. Etude des interactions bidirectionnelles entre le microbiote intestinal et les récepteurs aux xénobiotiques CAR et PXR : Insights into the bidirectional interactions between the gut microbiota and the xenobiotic receptors CAR and PXR. [Doctoral Dissertation]. Université Toulouse III – Paul Sabatier; 2019. Available from: http://www.theses.fr/2019TOU30233

2. Xu, Chenshu. REGULATION OF DRUG METABOLISM AND INFLAMMATION BY PREGNANE X RECEPTOR.

Degree: PhD, Pharmacology & Toxicology, 2011, University of Kansas

URL: http://hdl.handle.net/1808/9708

► Liver-enriched nuclear receptor (NR) proteins regulate the expression and activity of several pivotal hepatic biochemical pathways including the uptake, metabolism and excretion of cholesterol, bile… (more)

▼ Liver-enriched nuclear receptor (NR) proteins regulate the expression and activity of several pivotal hepatic biochemical pathways including the uptake, metabolism and excretion of cholesterol, bile acids, glucose, and xenobiotic compounds from the body. The pregnane x receptor (PXR, NR1I2) was first identified in 1998 as a member of the NR superfamily. Over the past decade, it has been well established that PXR functions as a master-regulator of xenobiotic- and drug-inducible expression and activity of numerous genes that encode key members of the phase I and phase II metabolic enzymes, as well as several membrane transporter proteins. In this way, activation of PXR serves as the principal defense mechanism defending the body from toxic insult. Similarly, the PXR protein also forms the molecular basis of an important class of drug-drug interactions in the clinical setting. Moreover, ligand-activated PXR negatively regulates inflammatory processes in both liver and intestine. An integrated model is emerging to reveal a key role for the post-translational modification of PXR in the selective suppression of gene expression, and is opening the door to the study of completely new modes of PXR-mediated gene regulation. This dissertation contributes mainly to two key areas of PXR research: (1) Identification a novel PXR target gene- carboxylesterase 6 (Ces6); (2) a study of the SUMOylation and ubiquitination of PXR protein. The results presented in this dissertation were primarily obtained from mouse and cell-culture systems. Data presented here reveal that activation of the inflammatory response modulates the SUMOylation and ubiquitination status of ligand-bound PXR protein. The SUMOylation and ubiquitination of the PXR protein functions to feedback-repress the inflammatory and xenobiotic responses, respectively. Taken together, the data represent a likely mechanism and provides initial molecular details for the connection between the PXR signaling pathway and inflammation. Studies on post-translational modification of PXR indicate how this protein is converted from a positive regulator in drug metabolism into a transcriptional repressor in inflammatory response. Finally, detailed protocols for purification of mammalian proteins necessary to perform in vitro SUMOylation reactions are presented. Taken together, the work presented in this dissertation contributes to understanding the interface between PXR, drug metabolism, and inflammation, which is expected to produce new opportunities for the development of novel therapeutic strategies. Advisors/Committee Members: Staudinger, Jeff L. (advisor), Dobrowsky, Rick T (cmtemember), Shi, Honglian (cmtemember), Moise, Alex (cmtemember), Lundquist, Erik A. (cmtemember).

Subjects/Keywords: Pharmacology; Toxicology; Carboxylesterase; Constitutive androstane receptor; Inflammation; Pregnane x receptor; Sumoylation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Xu, C. (2011). REGULATION OF DRUG METABOLISM AND INFLAMMATION BY PREGNANE X RECEPTOR. (Doctoral Dissertation). University of Kansas. Retrieved from http://hdl.handle.net/1808/9708

Chicago Manual of Style (16^th Edition):

Xu, Chenshu. “REGULATION OF DRUG METABOLISM AND INFLAMMATION BY PREGNANE X RECEPTOR.” 2011. Doctoral Dissertation, University of Kansas. Accessed March 04, 2021. http://hdl.handle.net/1808/9708.

MLA Handbook (7^th Edition):

Xu, Chenshu. “REGULATION OF DRUG METABOLISM AND INFLAMMATION BY PREGNANE X RECEPTOR.” 2011. Web. 04 Mar 2021.

Vancouver:

Xu C. REGULATION OF DRUG METABOLISM AND INFLAMMATION BY PREGNANE X RECEPTOR. [Internet] [Doctoral dissertation]. University of Kansas; 2011. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1808/9708.

Council of Science Editors:

Xu C. REGULATION OF DRUG METABOLISM AND INFLAMMATION BY PREGNANE X RECEPTOR. [Doctoral Dissertation]. University of Kansas; 2011. Available from: http://hdl.handle.net/1808/9708

3. Breuker, Cyril. Etude des xénorécepteurs CAR (NR1I3) et PXR (NR1I2) : identification d’un nouveau gène cible de CAR (SPOT14) et d’une nouvelle isoforme de PXR (PXR-small) dans l'hépatocyte humain : Study of the CAR (NR1I3) and PXR (NR1I2) : identification of a new CAR target gene (SPOT14) and a new PXR isoform (PXR-small) in human hepatocyte.

Degree: Docteur es, Sciences du médicament, 2010, Université Montpellier I

URL: http://www.theses.fr/2010MON13522

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CAR (Constitutive Androstane Receptor, NR1I3) et PXR (Pregnane X Receptor, NR1I2) sont deux récepteurs nucléaires dédiés à la reconna issance et à l'élimination de molécules… (more)

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CAR (Constitutive Androstane Receptor, NR1I3) et PXR (Pregnane X Receptor, NR1I2) sont deux récepteurs nucléaires dédiés à la reconna issance et à l'élimination de molécules lipophiles potentiellement toxiques pour l'organisme. Ces facteurs de transcription peuvent être activés par des ligands d'origines et de structures diverses (médicaments, polluants environnementaux, produits de l'alimentation et de phytothérapies). L'activation de ces récepteurs entraîne l'expression des gènes majeurs de la fonction de détoxication entéro-hépatique (CYP450, transférases, transporteurs) permettant l'élimination de ces toxiques. Dans ce travail, nous avons dans un premier temps 1) montré que CAR contrôle l'expression de Spot14, une protéine pro-lipogénique, et 2) nous avons identifié une nouvelle isoforme de PXR (PXR-small) codant uniquement pour le domaine de liaison des ligands de PXR. Nous avons pu déterminer les origines de transcription par 5'-RACE PCR et montrer que PXR-small représente environ 10% de l'ensemble des transcrits de PXR dans le tissu hépatique sain par une approche de PCR qua ntitative. Nous avons pu détecter sa présence par western-blot sur des extraits de protéines nucléaires issus de tissus hépatiques et de lignées cellulaires hépatiques. Par des expériences de gel retard, nous avons observé que cette nouvelle isoforme tronquée, qui ne code que pour le LBD de PXR, ne peut pas se lier à l'ADN. Des expériences de gènes rapporteurs suggèrent que cette isoforme se comporte comme un dominant négatif de PXR. Enfin, la présence d'un ilot CpG situé juste en amont de PXR-small suggère que cette nouvelle isoforme pourrait être régulée épigénétiquement par méthylation, notamment dans les cellules tumorales.

CAR (Constitutive Androstane Receptor, NR1I3) and PXR (Pregnane X Receptor, NR1I2) are two nuclear receptors devoted to the recognition and elimination of lipohilic molecules potentially toxic to the body.These transcription factors can be activated by ligands of different origins and structures (drugs, environmental pollutants, food products and herbal medicine...). The activation of these receptors leads to the expression of major genes of the detoxification process (CYP450, transferases, transporters) leading to the elimination of these toxics. In this work, we 1) showed that Spot14, a pro-lipogenic protein, is a target gene of CAR, then 2) we identified a novel isoform of PXR (PXR-small), coding only the ligand binding domain of PXR. By using 5'-RACE PXR, we established the origins of transcription of PXR-small and by quantitative PCR we observed that PXR-small represents about 10% of all PXR transcripts in human liver. By using western blo t, we detect its presence on nuclear protein extracts from liver tissues and hepatic cell lines. In Electromobility shift essays experiments, we observed that PXR-small cannot bind to DNA, while reporter essay experiments suggest that this isoform acts as a dominant negative of PXR. Finally, the presence of a CpG island just upstream of PXR-small suggests that this novel…

Advisors/Committee Members: Pascussi, Jean-Marc (thesis director), Lumbroso, Serge (thesis director).

Subjects/Keywords: Récepteur nucléaire; Pregnane X Receptor; Constitutive Androstane Receptor; Métabolisme des médicaments; Perturbateur métabolique; Nuclear receptor; Pregnane X Receptor; Constitutive Androstane Receptor; Drugs metabolism; Metabolic disruptive

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Breuker, C. (2010). Etude des xénorécepteurs CAR (NR1I3) et PXR (NR1I2) : identification d’un nouveau gène cible de CAR (SPOT14) et d’une nouvelle isoforme de PXR (PXR-small) dans l'hépatocyte humain : Study of the CAR (NR1I3) and PXR (NR1I2) : identification of a new CAR target gene (SPOT14) and a new PXR isoform (PXR-small) in human hepatocyte. (Doctoral Dissertation). Université Montpellier I. Retrieved from http://www.theses.fr/2010MON13522

Chicago Manual of Style (16^th Edition):

Breuker, Cyril. “Etude des xénorécepteurs CAR (NR1I3) et PXR (NR1I2) : identification d’un nouveau gène cible de CAR (SPOT14) et d’une nouvelle isoforme de PXR (PXR-small) dans l'hépatocyte humain : Study of the CAR (NR1I3) and PXR (NR1I2) : identification of a new CAR target gene (SPOT14) and a new PXR isoform (PXR-small) in human hepatocyte.” 2010. Doctoral Dissertation, Université Montpellier I. Accessed March 04, 2021. http://www.theses.fr/2010MON13522.

MLA Handbook (7^th Edition):

Breuker, Cyril. “Etude des xénorécepteurs CAR (NR1I3) et PXR (NR1I2) : identification d’un nouveau gène cible de CAR (SPOT14) et d’une nouvelle isoforme de PXR (PXR-small) dans l'hépatocyte humain : Study of the CAR (NR1I3) and PXR (NR1I2) : identification of a new CAR target gene (SPOT14) and a new PXR isoform (PXR-small) in human hepatocyte.” 2010. Web. 04 Mar 2021.

Vancouver:

Breuker C. Etude des xénorécepteurs CAR (NR1I3) et PXR (NR1I2) : identification d’un nouveau gène cible de CAR (SPOT14) et d’une nouvelle isoforme de PXR (PXR-small) dans l'hépatocyte humain : Study of the CAR (NR1I3) and PXR (NR1I2) : identification of a new CAR target gene (SPOT14) and a new PXR isoform (PXR-small) in human hepatocyte. [Internet] [Doctoral dissertation]. Université Montpellier I; 2010. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2010MON13522.

Council of Science Editors:

Breuker C. Etude des xénorécepteurs CAR (NR1I3) et PXR (NR1I2) : identification d’un nouveau gène cible de CAR (SPOT14) et d’une nouvelle isoforme de PXR (PXR-small) dans l'hépatocyte humain : Study of the CAR (NR1I3) and PXR (NR1I2) : identification of a new CAR target gene (SPOT14) and a new PXR isoform (PXR-small) in human hepatocyte. [Doctoral Dissertation]. Université Montpellier I; 2010. Available from: http://www.theses.fr/2010MON13522

4. Leguelinel, Géraldine. Rôle des récepteurs des xénobiotiques CAR (Constitutive Androstane Receptor, NR1I3) et PXR (Pregnane X receptor, NR1I2) dans le métabolisme des chimiothérapies conventionnelles du cancer colorectal : Role of xenoreceptors CAR (Constitutive Androstane Receptor, NR1I3) and PXR (Pregnane X Receptor, NR1I2) in the metabolism of conventionnal chemotherapy in colorectal cancer.

Degree: Docteur es, Biologie Santé, 2011, Université Montpellier I

URL: http://www.theses.fr/2011MON13512

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Le cancer colorectal est marqué par une importante mortalité dans les stades avancés du fait du fort taux de récidives tumorales après chimiothérapie. La prédiction… (more)

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Le cancer colorectal est marqué par une importante mortalité dans les stades avancés du fait du fort taux de récidives tumorales après chimiothérapie. La prédiction de l'efficacité et de la toxicité des cytotoxiques s'impose comme un des enjeux majeurs de ces prochaines années. Parce que la majorité des anticancéreux sont pris en charge par les enzymes et transporteurs dont l'expression est contrôlée par le niveau d'expression et d'activation des xénosenseurs CAR et PXR, il est fort probable que ces xénosenseurs puissent représenter des facteurs prédictifs à prendre en compte dans la prise en charge des cancers. Notre équipe a récemment montré que les récepteurs des xénobiotiques PXR (NR1I2) (Raynal et al, 2010) et CAR (NR1I3) sont exprimés dans des lignées cellulaires et des tissus coliques humains. Leur surexpression dans les lignées coliques LS174T et T84 entraine leur résistance à l'irinotécan et à son métabolite actif le SN38 alors que leur inhibition antagonise cette résistance. Des dosages intra- et extra-cellulaires du SN38 et du SN38-G, ainsi que la quantification des ARNm des l'UGT1As et du transporteur MDR1, montrent que CAR et PXR augmentent le métabolisme détoxifiant et l'efflux du SN38. L'impact de la surexpression de ces xénosenseurs sur la viabilité des cellules LS174T à différentes classes de cytotoxiques (anti-métabolites, intercalants, inhibiteurs de topoisomérases, poisons du fuseau) a ensuite été évaluée. Nous avons observé que l'expression de CAR ou PXR conduit à une forte chimiorésistance au paclitaxel, au docétaxel et au 4-hydroxy-cyclophosphamide alors que PXR entraîne une sensibilisation marquée au cisplatine et au carboplatine en augmentant la quantité d'adduits de platine sur l'ADN. Les études du transcriptome de nos modèles cellulaires nous ont permis d'identifier les gènes cibles impliqués dans ces variations de cytotoxicité. Des études de confirmation par modulation pharmacologique ou ARNs interférents de ces gènes cibles sont en cours et nous permettront de préciser les mécanismes mis en jeu dans les variations de chimiosensibilité. Ces travaux devraient permettent de mieux appréhender le rôle des xénosenseurs CAR et PXR sur le métabolisme intra-tumoral des cytotoxiques et potentiellement sur la réponse à des chimiothérapies variées.

Colorectal cancer is characterized by high mortality in advanced stages due to the high rate of tumor recurrence after chemotherapy. The prediction of the efficacy and toxicity of cytotoxic drugs represents a major challenge in the coming years. Because the majority of cancer drugs are supported by the enzymes and transporters whose expression is controlled by the level of expression and activation of the xenosensors CAR (NR1I3) and PXR (NR1I2), it is likely that they may represent predictive factors in the management of cancer. Our team has recently shown that xenobiotic receptors PXR (Raynal et al, 2010) and CAR are expressed in cell lines and human colon tissues. Their overexpression in colon cancer cell lines LS174T and T84 leads to resistance to…

Advisors/Committee Members: Pascussi, Jean-Marc (thesis director), Evrard, Alexandre (thesis director).

Subjects/Keywords: Xénorécepteurs; Métabolisme intratumoral; Cancer colorectal; Chimiosensibilité; Constitutive Androstane Receptor; Pregnane X Receptor; Xenoreceptors; Intratumoral metabolism; Colorectal cancer; Chemosensibility; Constitutive Androstane Receptor; Pregnane X Receptor

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Leguelinel, G. (2011). Rôle des récepteurs des xénobiotiques CAR (Constitutive Androstane Receptor, NR1I3) et PXR (Pregnane X receptor, NR1I2) dans le métabolisme des chimiothérapies conventionnelles du cancer colorectal : Role of xenoreceptors CAR (Constitutive Androstane Receptor, NR1I3) and PXR (Pregnane X Receptor, NR1I2) in the metabolism of conventionnal chemotherapy in colorectal cancer. (Doctoral Dissertation). Université Montpellier I. Retrieved from http://www.theses.fr/2011MON13512

Chicago Manual of Style (16^th Edition):

Leguelinel, Géraldine. “Rôle des récepteurs des xénobiotiques CAR (Constitutive Androstane Receptor, NR1I3) et PXR (Pregnane X receptor, NR1I2) dans le métabolisme des chimiothérapies conventionnelles du cancer colorectal : Role of xenoreceptors CAR (Constitutive Androstane Receptor, NR1I3) and PXR (Pregnane X Receptor, NR1I2) in the metabolism of conventionnal chemotherapy in colorectal cancer.” 2011. Doctoral Dissertation, Université Montpellier I. Accessed March 04, 2021. http://www.theses.fr/2011MON13512.

MLA Handbook (7^th Edition):

Leguelinel, Géraldine. “Rôle des récepteurs des xénobiotiques CAR (Constitutive Androstane Receptor, NR1I3) et PXR (Pregnane X receptor, NR1I2) dans le métabolisme des chimiothérapies conventionnelles du cancer colorectal : Role of xenoreceptors CAR (Constitutive Androstane Receptor, NR1I3) and PXR (Pregnane X Receptor, NR1I2) in the metabolism of conventionnal chemotherapy in colorectal cancer.” 2011. Web. 04 Mar 2021.

Vancouver:

Leguelinel G. Rôle des récepteurs des xénobiotiques CAR (Constitutive Androstane Receptor, NR1I3) et PXR (Pregnane X receptor, NR1I2) dans le métabolisme des chimiothérapies conventionnelles du cancer colorectal : Role of xenoreceptors CAR (Constitutive Androstane Receptor, NR1I3) and PXR (Pregnane X Receptor, NR1I2) in the metabolism of conventionnal chemotherapy in colorectal cancer. [Internet] [Doctoral dissertation]. Université Montpellier I; 2011. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2011MON13512.

Council of Science Editors:

Leguelinel G. Rôle des récepteurs des xénobiotiques CAR (Constitutive Androstane Receptor, NR1I3) et PXR (Pregnane X receptor, NR1I2) dans le métabolisme des chimiothérapies conventionnelles du cancer colorectal : Role of xenoreceptors CAR (Constitutive Androstane Receptor, NR1I3) and PXR (Pregnane X Receptor, NR1I2) in the metabolism of conventionnal chemotherapy in colorectal cancer. [Doctoral Dissertation]. Université Montpellier I; 2011. Available from: http://www.theses.fr/2011MON13512

5. Roques, Beatrice. Bases mécanistiques des effets d'un insecticide agrovétérinaire, le fiproni, et/ou de ses métabolites sur la fonction thyroïdienne chez le rat : Mechanistic basis of the effects of an agroveterinary insecticide, the fipronil, and/or its metabolites on the thyroid function in rat.

Degree: Docteur es, Pathologie, Toxicologie, Génétique et Nutrition, 2012, Toulouse, INSA

URL: http://www.theses.fr/2012ISAT0029

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Le fipronil, insecticide largement utilisé, est un perturbateur thyroïdien chez le rat modulant le catabolisme hépatique des hormones thyroïdiennes. Ses effets chez le mouton, considéré… (more)

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Le fipronil, insecticide largement utilisé, est un perturbateur thyroïdien chez le rat modulant le catabolisme hépatique des hormones thyroïdiennes. Ses effets chez le mouton, considéré comme un modèle plus pertinent que le rat pour étudier une régulation de la fonction thyroïdienne chez l'Homme, sont plus limités. Le but de cette thèse était de caractériser au niveau hépatique le mode d'action du fipronil sur la fonction thyroïdienne en s'intéressant 1) au rôle potentiel du principal métabolite du fipronil formé in vivo, le fipronil sulfone, et 2) aux différences interspécifiques de métabolisme du fipronil et/ou de sensibilité à la perturbation thyroïdienne qui peuvent préjuger de la pertinence des différents modèles animaux pour l'analyse du risque du fipronil pour la santé humaine. L'efficacité du fipronil sulfone à induire l'expression et/ou l'activité d'enzymes responsables du métabolisme hépatique des hormones thyroïdiennes ou du fipronil était la même que celle du fipronil autant in vivo chez le rat que in vitro sur hépatocytes. L'utilisation d'un modèle de souris déficientes pour des récepteurs nucléaires xénosenseurs suggérait fortement une implication des récepteurs nucléaires Constitutive Androstane Receptor et/ou Pregnane X Receptor dans la perturbation thyroïdienne induite par le fipronil

The widely used insecticide fipronil is a thyroid disruptor in rat acting on thyroid hormone hepatic metabolism. In sheep, a more relevant species for the human thyroid regulation, fipronil-induced thyroid-disruption is much more limited. The goal of this thesis was to characterize the mode of action of fipronil on thyroid function at the hepatic level focusing on 1) the potential role of fipronil sulfone, the main fipronil metabolite formed in vivo, and on 2) interspecific differences in terms of fipronil metabolism and/or sensitivity to thyroid disruption that can prejudge of the relevance of the different animal models for the risk assessment of fipronil for human health. Fipronil sulfone was as efficient as fipronil to induce the expression and/or activity of enzymes involved in thyroid hormone or fipronil hepatic metabolism both in vivo in rat and in vitro on hepatocytes. The use of knock-out mice for xenosensors nuclear receptors strongly suggested an implication of the nuclear receptor Constitutive Androstane Receptor and/or Pregnane X Receptor on fipronil-induced thyroid disruption

Advisors/Committee Members: Viguié, Catherine (thesis director), Martin, Pascal Guy Pierre (thesis director).

Subjects/Keywords: Perturbateur endocrinien; Fipronil; Fipronil sulfone; Fonction thyroïdienne; Métabolisme hépatique; Rat; Souris transgéniques; Hépatocytes; Constitutive Androstane Receptor; Pregnane X Receptor; Endocrine disruptor; Fipronil; Fipronil sulfone; Thyroid function; Hepatic metabolism; Rat; Transgenic mice; Hepatocytes; Constitutive Androstane Receptor; Pregnane X Receptor; 613

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Roques, B. (2012). Bases mécanistiques des effets d'un insecticide agrovétérinaire, le fiproni, et/ou de ses métabolites sur la fonction thyroïdienne chez le rat : Mechanistic basis of the effects of an agroveterinary insecticide, the fipronil, and/or its metabolites on the thyroid function in rat. (Doctoral Dissertation). Toulouse, INSA. Retrieved from http://www.theses.fr/2012ISAT0029

Chicago Manual of Style (16^th Edition):

Roques, Beatrice. “Bases mécanistiques des effets d'un insecticide agrovétérinaire, le fiproni, et/ou de ses métabolites sur la fonction thyroïdienne chez le rat : Mechanistic basis of the effects of an agroveterinary insecticide, the fipronil, and/or its metabolites on the thyroid function in rat.” 2012. Doctoral Dissertation, Toulouse, INSA. Accessed March 04, 2021. http://www.theses.fr/2012ISAT0029.

MLA Handbook (7^th Edition):

Roques, Beatrice. “Bases mécanistiques des effets d'un insecticide agrovétérinaire, le fiproni, et/ou de ses métabolites sur la fonction thyroïdienne chez le rat : Mechanistic basis of the effects of an agroveterinary insecticide, the fipronil, and/or its metabolites on the thyroid function in rat.” 2012. Web. 04 Mar 2021.

Vancouver:

Roques B. Bases mécanistiques des effets d'un insecticide agrovétérinaire, le fiproni, et/ou de ses métabolites sur la fonction thyroïdienne chez le rat : Mechanistic basis of the effects of an agroveterinary insecticide, the fipronil, and/or its metabolites on the thyroid function in rat. [Internet] [Doctoral dissertation]. Toulouse, INSA; 2012. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2012ISAT0029.

Council of Science Editors:

Roques B. Bases mécanistiques des effets d'un insecticide agrovétérinaire, le fiproni, et/ou de ses métabolites sur la fonction thyroïdienne chez le rat : Mechanistic basis of the effects of an agroveterinary insecticide, the fipronil, and/or its metabolites on the thyroid function in rat. [Doctoral Dissertation]. Toulouse, INSA; 2012. Available from: http://www.theses.fr/2012ISAT0029

University of Arizona

6. Beilke, Lisa D. Mechanisms of Hepatoprotection in a Murine Model of Bile Acid-Induced Intrahepatic Cholestasis .

Degree: 2008, University of Arizona

URL: http://hdl.handle.net/10150/194264

► There are many causes of cholestasis, which results when the flow of bile acids is slowed or stopped. Bile acids are hydrophobic molecules synthesized from… (more)

▼ There are many causes of cholestasis, which results when the flow of bile acids is slowed or stopped. Bile acids are hydrophobic molecules synthesized from cholesterol in the liver, and when present in excess, are cytotoxic to cell membranes. Treatment options for cholestasis are limited, and if left untreated or inadequately treated, many patients will require a liver transplant; thus, underscoring the importance of successfully managing this disease. Activation of nuclear receptors in animal models has been shown to be hepatoprotective during bile acid-induced cholestasis; however, the mechanisms underlying the hepatoprotective effects are poorly understood. Therefore, the over-arching goal of this project is to glean an improved comprehension of the mechanisms of hepatoprotection during bile acid-induced cholestasis. All of the studies involve administration of CAR activators phenobarbital (PB), oltipraz (OPZ), 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene [TCPOBOP (TC)] or corn oil (CO) to C57BL/6 wild type (WT), or WT and CAR knockout (CAR-/-) mice prior to induction of intrahepatic cholestasis using the secondary bile acid lithocholic acid (LCA). Efflux transport proteins such as Mrps 3 and 4 are known to be up-regulated during cholestasis, and this was the first topic of exploration. Unexpectedly, the expression of efflux transporters was not consistently up-regulated in protected mice. However, a decrease in total liver bile acid concentrations was observed. These changes in hepatic bile acids indicated that bile acid biosynthesis may be relevant to hepatoprotection. Indeed decreases in total and individual bile acids correlated with hepatoprotection, and Cyp8b1 expression was also increased which could be suggestive of a shift in the bile acid biosynthesis pathway towards the formation of less toxic bile acid species. CAR may also have a role in cell death via apoptosis by altering Bcl-2 protein expression. Although apoptosis was decreased in hepatoprotected mice, an increase in the expression of Mcl-1 and Bcl-xL was not observed, suggesting hepatoprotection is not a direct result of CAR-induced Mcl-1 expression. These findings add significantly to the body of knowledge surrounding cholestatic liver disease and suggest that studies aimed toward manipulation of nuclear receptors are worthy of further exploration. Advisors/Committee Members: Cherrington, Nathan J (advisor), Gandolfi, A. Jay (committeemember), Futscher, Bernard W. (committeemember), Regan, John W. (committeemember).

Subjects/Keywords: Cholestasis; bile acid; biosynthesis; apoptosis; constitutive androstane receptor

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Beilke, L. D. (2008). Mechanisms of Hepatoprotection in a Murine Model of Bile Acid-Induced Intrahepatic Cholestasis . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/194264

Chicago Manual of Style (16^th Edition):

Beilke, Lisa D. “Mechanisms of Hepatoprotection in a Murine Model of Bile Acid-Induced Intrahepatic Cholestasis .” 2008. Doctoral Dissertation, University of Arizona. Accessed March 04, 2021. http://hdl.handle.net/10150/194264.

MLA Handbook (7^th Edition):

Beilke, Lisa D. “Mechanisms of Hepatoprotection in a Murine Model of Bile Acid-Induced Intrahepatic Cholestasis .” 2008. Web. 04 Mar 2021.

Vancouver:

Beilke LD. Mechanisms of Hepatoprotection in a Murine Model of Bile Acid-Induced Intrahepatic Cholestasis . [Internet] [Doctoral dissertation]. University of Arizona; 2008. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10150/194264.

Council of Science Editors:

Beilke LD. Mechanisms of Hepatoprotection in a Murine Model of Bile Acid-Induced Intrahepatic Cholestasis . [Doctoral Dissertation]. University of Arizona; 2008. Available from: http://hdl.handle.net/10150/194264

7. Sberna, Anne-Laure. Etude du rôle du récepteur nucléaire CAR, Constitutive Androstane Receptor, dans le métabolisme des lipides et la susceptibilité à l'athérosclérose : Role of the nuclear receptor CAR, constitutive androstane receptor, in lipoprotein metabolism and atherosclerosis.

Degree: Docteur es, Sciences de l'alimentation, 2011, Université de Bourgogne

URL: http://www.theses.fr/2011DIJOS094

► Le récepteur CAR, Constitutive Androstane Receptor, appartient à la-famille NR1 des récepteurs nucléaires. Initialement décrit comme un récepteur orphelin, CAR est en fait activé par… (more)

▼ Le récepteur CAR, Constitutive Androstane Receptor, appartient à la-famille NR1 des récepteurs nucléaires. Initialement décrit comme un récepteur orphelin, CAR est en fait activé par un grand nombre de molécules exogènes et une des fonctions principales de CAR est celle de xénosenseur. L’activation CAR par ses différents ligands stimule la transcription des enzymes de phase I, II et III nécessaires à la détoxification et à l’élimination des xénobiotiques. Parallèlement, CAR a fait l’objet de nombreux travaux indépendants qui ont démontré son implication dans le métabolisme de molécules endogènes comme les acides biliaires, la bilirubine et les hormones thyroïdiennes. Plus récemment un impact de CAR sur des voies métaboliques fondamentales comme la néoglucogenèse, la lipogenèse et le métabolisme des lipoprotéines a été mis en évidence faisant de CAR au même titre que les récepteurs du groupe NR1 (LXR et FXR) une cible potentielle pour l’étude et le traitement du syndrome métabolique et des maladies cardio-vasculaires. Dans le cadre de ce mémoire nous avons étudié l’impact d’une stimulation chronique de CAR par un agoniste spécifique le TCPOBOP sur le transport reverse du cholestérol, le métabolisme des lipoprotéines et la susceptibilité à l’athérosclérose dans un contexte de surcharge alimentaire en cholestérol. Chez les souris dyslipidémiques déficientes pour le gène du récepteur aux lipoprotéines de faible densité (Ldlr-/-) ou bien déficientes pour l’apoprotéine E l’activation spécifique de CAR par l’agoniste TCPOBOP (3,3’,5,5’-Tétrachloro-1,4-bis (pyridyloxy )benzene), 1) diminue la lipogenèse via l’induction du facteur Insig1 et la répression du facteur de transcription Srebp1c et de ses gènes cibles. Cela se traduit par une diminution de la triglycéridémie plasmatique associée à une diminution du contenu hépatique en triglycérides et une diminution de la sécrétion de lipoprotéines riches en triglycérides, 2) stimule la conversion et l’élimination fécale du cholestérol sous forme d’acides biliaires ce qui se traduit par une élimination accrue du cholestérol dérivé des HDL dans les fèces, dernière étape du transport reverse du cholestérol, 3) diminue le taux de cholestérol associé aux LDL chez les souris Ldlr-/- probablement par stimulation de l’expression hépatique du récepteur aux lipoprotéines de très basse densité. La diminution de l’athérogénicité du profil lipoprotéique et la stimulation du transport reverse du cholestérol sont associées à une réduction des lésions athéromateuses au niveau des valves et de la crosse aortique chez les souris Ldlr-/-. Une diminution des lésions athéromateuses uniquement au niveau de la crosse aortique est également observée chez les souris ApoE-/- L’ensemble des travaux présentés et les récentes études publiées suggèrent que CAR peut être considéré comme un acteur central du métabolisme lipidique et font de ce récepteur nucléaire une nouvelle cible potentielle pour l’étude et le traitement des désordres métaboliques comme le diabète, l’obésité, la stéatose hépatique et… Advisors/Committee Members: Lagrost, Laurent (thesis director), Masson, David (thesis director).

Subjects/Keywords: CAR (Constitutive Androstane Receptor); (3,3’,5,5’-Tétrachloro-1,4-bis(pyridyloxy)benzene); VLDL récepteur; Triglycérides; Acides biliaires; Athérosclérose; CAR (Constitutive Androstane Receptor); TCPOBOP (3,3',5,5'-Tetrachloro-1,4-bis(pyridyloxy)benzene); VLDL receptor; Triglycerides; Bile acids; Atherosclerosis; 572.4; 612.3; 616.1

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Sberna, A. (2011). Etude du rôle du récepteur nucléaire CAR, Constitutive Androstane Receptor, dans le métabolisme des lipides et la susceptibilité à l'athérosclérose : Role of the nuclear receptor CAR, constitutive androstane receptor, in lipoprotein metabolism and atherosclerosis. (Doctoral Dissertation). Université de Bourgogne. Retrieved from http://www.theses.fr/2011DIJOS094

Chicago Manual of Style (16^th Edition):

Sberna, Anne-Laure. “Etude du rôle du récepteur nucléaire CAR, Constitutive Androstane Receptor, dans le métabolisme des lipides et la susceptibilité à l'athérosclérose : Role of the nuclear receptor CAR, constitutive androstane receptor, in lipoprotein metabolism and atherosclerosis.” 2011. Doctoral Dissertation, Université de Bourgogne. Accessed March 04, 2021. http://www.theses.fr/2011DIJOS094.

MLA Handbook (7^th Edition):

Sberna, Anne-Laure. “Etude du rôle du récepteur nucléaire CAR, Constitutive Androstane Receptor, dans le métabolisme des lipides et la susceptibilité à l'athérosclérose : Role of the nuclear receptor CAR, constitutive androstane receptor, in lipoprotein metabolism and atherosclerosis.” 2011. Web. 04 Mar 2021.

Vancouver:

Sberna A. Etude du rôle du récepteur nucléaire CAR, Constitutive Androstane Receptor, dans le métabolisme des lipides et la susceptibilité à l'athérosclérose : Role of the nuclear receptor CAR, constitutive androstane receptor, in lipoprotein metabolism and atherosclerosis. [Internet] [Doctoral dissertation]. Université de Bourgogne; 2011. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2011DIJOS094.

Council of Science Editors:

Sberna A. Etude du rôle du récepteur nucléaire CAR, Constitutive Androstane Receptor, dans le métabolisme des lipides et la susceptibilité à l'athérosclérose : Role of the nuclear receptor CAR, constitutive androstane receptor, in lipoprotein metabolism and atherosclerosis. [Doctoral Dissertation]. Université de Bourgogne; 2011. Available from: http://www.theses.fr/2011DIJOS094

Penn State University

8. Zamule, Stephanie M. ROLE OF THE CONSTITUTIVE ANDROSTANE RECEPTOR IN THE DERIVATION OF HEPATIC-LIKE CELLS FROM HUMAN EMBRYONIC STEM CELLS.

Degree: 2010, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/10496

► The liver performs an array of functions vital to life including detoxification, production of serum proteins, maintenance of cholesterol homeostasis, production and clearance of bile… (more)

▼ The liver performs an array of functions vital to life including detoxification, production of serum proteins, maintenance of cholesterol homeostasis, production and clearance of bile components, assembly and inter-conversion of amino acids, synthesis and breakdown of glucose, and processing of fatty acids. Current treatments for liver failure are inadequate, relying on liver or hepatocyte transplantation, both of which are significantly limited by insufficient donor tissue, donor-to-donor variability in tissue quality, and the risk of rejection, infection, or adverse immune response in the recipient. Human embryonic stem cells (hESCs) – derived from the inner cell mass of developing blastocysts and capable of giving rise to any cell type in the body upon exposure to the appropriate conditions – offer promise as an alternative source of cells from which a supply of hepatocytes may be derived for therapeutic transplantations. Hepatocytes derived from hESCs would also potentially provide a repository of cells for pharmacological and toxicological studies which rely on hepatocytes obtained from human donors as models for drug metabolism research and predictors of toxicological responses that may be associated with exposure to xenobiotic compounds. While a number of studies have demonstrated that hESCs are capable of differentiating into hepatic precursors, the precise means by which these cells may be derived, and the genes governing this multifaceted process, have yet to be fully elucidated. In this investigation we employed a unique hepatic differentiation protocol in which hESCs are cultured for only 10 days on collagen matrix in our hepatocyte media (William’s E Media supplemented with HEPES, glutamine, antibiotics, dexamethasone, insulin, transferrin, selenium, and linoleic acid/albumin). The resulting cell population exhibits hepatic-like cell morphology and decreased expression of ‘stemness’ markers including certain transcription factors, surface antigens, and enzymes. The hESC-derived hepatic-like cells express enhanced levels of hepatic markers including transcription factors, nuclear receptors, liver-generated plasma proteins, protease inhibitors, metabolic enzymes, and biotransformation enzymes. Acquisition of hepatic function is confirmed by the cells’ ability to transport anionic compounds and store glycogen. Notably, expression of the constitutive androstane receptor (CAR) – a nuclear receptor which, in the adult liver, is involved in the regulation of diverse physiological processes including all three phases of hepatic biotransformation and elimination as well as energy metabolism and lipid homeostasis – is highly increased in the hepatic-like cells, to levels approaching those of cultures of primary human hepatocytes. CAR is also expressed robustly and consistently in human fetal liver tissue obtained from subjects of a range of gestational ages. Modulation of CAR levels in differentiating hESCs using a lentivirus system – which we demonstrate to stably and robustly transduce both hESCs and cultures… Advisors/Committee Members: Curtis John Omiecinski, Dissertation Advisor/Co-Advisor, Curtis John Omiecinski, Committee Chair/Co-Chair, Gong Chen, Committee Member, Peter John Hudson, Committee Member, Gary H Perdew, Committee Member, John Patrick Vanden Heuvel, Committee Member, Kent Eugene Vrana, Committee Member.

Subjects/Keywords: embryonic stem cells; constitutive androstane receptor; liver; differentiation; nuclear receptor; development; lentivirus

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zamule, S. M. (2010). ROLE OF THE CONSTITUTIVE ANDROSTANE RECEPTOR IN THE DERIVATION OF HEPATIC-LIKE CELLS FROM HUMAN EMBRYONIC STEM CELLS. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/10496

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zamule, Stephanie M. “ROLE OF THE CONSTITUTIVE ANDROSTANE RECEPTOR IN THE DERIVATION OF HEPATIC-LIKE CELLS FROM HUMAN EMBRYONIC STEM CELLS.” 2010. Thesis, Penn State University. Accessed March 04, 2021. https://submit-etda.libraries.psu.edu/catalog/10496.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zamule, Stephanie M. “ROLE OF THE CONSTITUTIVE ANDROSTANE RECEPTOR IN THE DERIVATION OF HEPATIC-LIKE CELLS FROM HUMAN EMBRYONIC STEM CELLS.” 2010. Web. 04 Mar 2021.

Vancouver:

Zamule SM. ROLE OF THE CONSTITUTIVE ANDROSTANE RECEPTOR IN THE DERIVATION OF HEPATIC-LIKE CELLS FROM HUMAN EMBRYONIC STEM CELLS. [Internet] [Thesis]. Penn State University; 2010. [cited 2021 Mar 04]. Available from: https://submit-etda.libraries.psu.edu/catalog/10496.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zamule SM. ROLE OF THE CONSTITUTIVE ANDROSTANE RECEPTOR IN THE DERIVATION OF HEPATIC-LIKE CELLS FROM HUMAN EMBRYONIC STEM CELLS. [Thesis]. Penn State University; 2010. Available from: https://submit-etda.libraries.psu.edu/catalog/10496

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North Carolina State University

9. Jackson, Jonathan Patrick. The Role of the Nuclear Receptors CAR and PXR in the Drug Induced Transcriptional Regulation of the Murine CYP2C Subfamily of Cytochrome P450 Monooxygenases.

Degree: PhD, Toxicology, 2007, North Carolina State University

URL: http://www.lib.ncsu.edu/resolver/1840.16/4828

► The CYP2C subfamily of cytochrome P450 monoxygenases (P450) is responsible for the metabolism of approximately 20% of therapeutic drugs. Recently, phenytoin has been reported to… (more)

▼ The CYP2C subfamily of cytochrome P450 monoxygenases (P450) is responsible for the metabolism of approximately 20% of therapeutic drugs. Recently, phenytoin has been reported to induce the expression of the human genes CYP2B6, CYP3A4, and CYP2C8. Cytochrome P450 expression is often induced by prior exposure to xenobiotics often resulting in drug-drug interactions. Induction of the human CYP2C enzymes by xenobiotics occurs at the transcriptional level and is reported to involve the constitutive androstane receptor (CAR) and/or the pregnane X receptor (PXR). However, the molecular mechanisms regulating drug induction of the murine CYP2C enzymes remain unclear. The mouse is an excellent model system to investigate CYP2C drug induced transcription due to the availability of nuclear receptor knockout mice. Herein, we report the identification of two phenobarbital and phenytoin inducible murine CYP2C genes, Cyp2c29 and Cyp2c37. Quantitative RT-PCR demonstrates that hepatic CYP2C29 and CYP2C37 mRNA is induced by phenobarbital and phenytoin. Additionally, immunoblots indicated that phenytoin induced hepatic CYP2C29 and CYP2C37 protein. We utilized in vivo gene reporter assays of the Cyp2c29 promoter to delineate the phenytoin-response activity to a phenytoin responsive module (PHREM) located -1371 bp upstream of the Cyp2c29 translation start site. Similarly, using in vitro gene reporter assays of the Cyp2c37 promoter, we identified a single functional CAR-RE located -2791 bp upstream of translation start site of Cyp2c37. Mutagenesis studies demonstrated that these sites are essential for CAR transactivation of their respective gene promoters in HepG2 cells. Using quantitative RT-PCR, we demonstrated that induction of CYP2B10 mRNA by phenytoin was completely abolished in CAR-null mice, but only moderately reduced in PXR-null mice. Similarly, phenytoin induction of CYP2C29 and CYP2C37 mRNA was severely reduced in CAR-null mice and only modestly reduced in PXR-null mice. Taken together, these results indicate that the induction of Cyp2b10, Cyp2c29, and Cyp2c37 by phenytoin is predominately regulated by mCAR. However, induction of CYP3A11 mRNA was only partially decreased in either null mice strain. Studies have demonstrated that CYP3A11 mRNA is induced by CAR and PXR agonists, thus our results also indicate that phenytoin acts as an agonist of both CAR and PXR. Advisors/Committee Members: Joyce A Goldstein, Ph.D., Committee Co-Chair (advisor), Randy Rose, Ph.D., Committee Co-Chair (advisor), Masahiko Negishi, Ph.D., Committee Member (advisor), Andrew Wallace, Ph.D., Committee Member (advisor), Ernest Hodgson, Ph.D., Committee Member (advisor).

Subjects/Keywords: Cyp2c37; Cyp2c29; Nuclear Receptors; Pregnane X Receptor; Constitutive Androstane Receptor; Phenytoin; Phenobarbital; Drug Induction

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Jackson, J. P. (2007). The Role of the Nuclear Receptors CAR and PXR in the Drug Induced Transcriptional Regulation of the Murine CYP2C Subfamily of Cytochrome P450 Monooxygenases. (Doctoral Dissertation). North Carolina State University. Retrieved from http://www.lib.ncsu.edu/resolver/1840.16/4828

Chicago Manual of Style (16^th Edition):

Jackson, Jonathan Patrick. “The Role of the Nuclear Receptors CAR and PXR in the Drug Induced Transcriptional Regulation of the Murine CYP2C Subfamily of Cytochrome P450 Monooxygenases.” 2007. Doctoral Dissertation, North Carolina State University. Accessed March 04, 2021. http://www.lib.ncsu.edu/resolver/1840.16/4828.

MLA Handbook (7^th Edition):

Jackson, Jonathan Patrick. “The Role of the Nuclear Receptors CAR and PXR in the Drug Induced Transcriptional Regulation of the Murine CYP2C Subfamily of Cytochrome P450 Monooxygenases.” 2007. Web. 04 Mar 2021.

Vancouver:

Jackson JP. The Role of the Nuclear Receptors CAR and PXR in the Drug Induced Transcriptional Regulation of the Murine CYP2C Subfamily of Cytochrome P450 Monooxygenases. [Internet] [Doctoral dissertation]. North Carolina State University; 2007. [cited 2021 Mar 04]. Available from: http://www.lib.ncsu.edu/resolver/1840.16/4828.

Council of Science Editors:

Jackson JP. The Role of the Nuclear Receptors CAR and PXR in the Drug Induced Transcriptional Regulation of the Murine CYP2C Subfamily of Cytochrome P450 Monooxygenases. [Doctoral Dissertation]. North Carolina State University; 2007. Available from: http://www.lib.ncsu.edu/resolver/1840.16/4828

University of Kansas

10. Pacyniak, Erik Kristofer. Molecular Mechanism of Polybrominated Diphenyl Ether Disposition in the Liver.

Degree: PhD, Pharmacology, Toxicology & Therapeutics, 2010, University of Kansas

URL: http://hdl.handle.net/1808/7717

► Polybrominated diphenyl ethers (PBDEs) were introduced in the late 1970's as additive flame retardants incorporated into textiles, electronics, plastics and furniture. Although 2,2',3,3',4,4',5,5',6,6'-decabromodiphenyl ether (BDE209)… (more)

▼ Polybrominated diphenyl ethers (PBDEs) were introduced in the late 1970's as additive flame retardants incorporated into textiles, electronics, plastics and furniture. Although 2,2',3,3',4,4',5,5',6,6'-decabromodiphenyl ether (BDE209) is the only congener currently on the market, 2,2`,4,4`-tetrabromodiphenyl ether (BDE47), 2,2`,4,4`,5-pentabromodiphenyl ether (BDE99), and 2,2`,4,4`,5,5`-hexabromodiphenyl ether (BDE153) are the predominant congeners detected in human and wildlife samples. Upon exposure, PBDEs enter the liver where they are biotransformed to potentially toxic metabolites. Although the human liver burden of PBDEs is not clear, the presence of PBDEs in human liver is particularly alarming because it has been demonstrated in rodents that hydroxylated metabolites may play a pivotal role in PBDE-mediated toxicity. The mechanism by which PBDEs enter the liver was not known. However, due to their large molecular weights (MWs ~485 to 1000 Da), they were not likely to enter hepatocytes by simple diffusion. Organic anion transporting polypeptides (OATPs: human; Oatps: rodents) are responsible for hepatic uptake of a variety of amphipathic compounds of MWs larger than 350 Da. Therefore, I tested the hypothesis that OATPs/Oatps expressed in human and mouse hepatocytes are responsible for the uptake of PBDE congeners 47, 99, and 153 by using Chinese hamster ovary (CHO) cell lines expressing OATP1B1, OATP1B3, or OATP2B1 and Human Embryonic Kidney 293 (HEK293) cells transiently expressing Oatp1a1, Oatp1a4, Oatp1b2, or Oatp2b1. Direct uptake studies illustrated that PBDE congeners are substrates of human and mouse hepatic OATPs/Oatps, except for Oatp1a1. Detailed kinetic analysis revealed that OATP1B1, OATP1B3, Oatp1a4, and Oatp1b2 transport BDE47 with the highest affinity followed by BDE99 and BDE153. However, both OATP2B1 and Oatp2b1 transported all three congeners with similar affinities. The importance of hepatic Oatps for the accumulation of BDE47 in liver was confirmed using Oatp1a4- and Oatp1b2-null mice. These results clearly suggest that uptake of PBDEs via these OATPs/Oatps are responsible for liver-specific accumulation of PBDEs. In mouse liver, PBDEs induce drug metabolizing enzymes, namely cytochrome P450s (Cyps). However, the molecular mechanisms underlying this induction was unknown. Cyp2b10 and 3a11 are target genes of the xenobiotic nuclear receptors, the constitutive androstane receptor (CAR) and pregnane X receptor (PXR), both of which are responsible for mediating induction of Cyp2b10 and Cyp3a11, respectively. I hypothesized that PBDE congeners are CAR and/or PXR activators. Using reporter-gene luciferase assays I showed that BDE47, BDE99 and BDE209 activate human and mouse CAR and PXR in a concentration-dependent manner. Furthermore, induction of Cyp2b10 and Cyp3a11 was markedly suppressed in CAR- and PXR-null mice, respectively, indicating that PBDE congeners activate these receptors in vivo. BDE47 and BDE99, the primary congeners detected in humans in the United States, are capable of inducing… Advisors/Committee Members: Guo, Grace L. (advisor), Hagenbuch, Bruno (cmtemember), Klaassen, Curtis D. (cmtemember), Reed, Gregory A. (cmtemember), Petroff, Brian K. (cmtemember).

Subjects/Keywords: Toxicology; Constitutive androstane receptor; Nuclear receptors; Organic anion transporting polypeptide; Polybrominated diphenyl ethers; Pregnane x receptor

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Pacyniak, E. K. (2010). Molecular Mechanism of Polybrominated Diphenyl Ether Disposition in the Liver. (Doctoral Dissertation). University of Kansas. Retrieved from http://hdl.handle.net/1808/7717

Chicago Manual of Style (16^th Edition):

Pacyniak, Erik Kristofer. “Molecular Mechanism of Polybrominated Diphenyl Ether Disposition in the Liver.” 2010. Doctoral Dissertation, University of Kansas. Accessed March 04, 2021. http://hdl.handle.net/1808/7717.

MLA Handbook (7^th Edition):

Pacyniak, Erik Kristofer. “Molecular Mechanism of Polybrominated Diphenyl Ether Disposition in the Liver.” 2010. Web. 04 Mar 2021.

Vancouver:

Pacyniak EK. Molecular Mechanism of Polybrominated Diphenyl Ether Disposition in the Liver. [Internet] [Doctoral dissertation]. University of Kansas; 2010. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1808/7717.

Council of Science Editors:

Pacyniak EK. Molecular Mechanism of Polybrominated Diphenyl Ether Disposition in the Liver. [Doctoral Dissertation]. University of Kansas; 2010. Available from: http://hdl.handle.net/1808/7717

Penn State University

11. De Keyser, Joshua Gordon. ALTERNATIVE SPLICING OF THE HUMAN CONSTITUTIVE ANDROSTANE RECEPTOR GENE CREATES RECEPTORS WITH UNIQUE FUNCTION AND LIGAND SPECIFICITY .

Degree: 2009, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/9350

► The human constitutive androstane receptor (CAR) regulates the expression of genes involved in xenobiotic metabolism in the liver. The CAR gene utilizes multiple alternative splicing… (more)

▼ The human constitutive androstane receptor (CAR) regulates the expression of genes involved in xenobiotic metabolism in the liver. The CAR gene utilizes multiple alternative splicing events during pre-mRNA processing, thereby increasing the CAR transcriptome. The work presented in this dissertation focuses on the functional analysis of a prominent human CAR variant, CAR2 that possesses a 4- amino acid insertion in the ligand binding domain. Previous investigations led us to hypothesize that the CAR2 variant is a ligand-activated receptor and possesses a unique ligand binding profile giving rise to novel biological function. We now demonstrate that CAR2 constitutes approximately one-third and one-half of the total CAR transcriptome in human hepatocytes and small intestine, respectively. Further, we identify the common plasticizers, di(2-ethylhexyl) phthalate (DEHP) and di-isononyl phthalate (DiNP) as highly potent and uniquely selective agonists of CAR2. Results from reporter transactivation assays reveal that DEHP and DiNP activate CAR2 at low nanomolar concentrations. In addition, comparative genomic analysis show that the typical mouse, rat and marmoset models of toxicity can not accurately profile potential human toxicity due to these species inability to generate a CAR2-like transcript. It is also demonstrated that CAR2 possesses an altered ligand pocket that allows for the highly potent and specific activation of the variant by DEHP and DiNP. Further studies show that CAR1 and CAR3 share similar ligand activation profiles; whereas CAR2 responds to most CAR1 and CAR3 ligands as well as a unique subset of chemicals. Finally, it is now shown that meclizine, a human CAR1 inverse-agonist, is a specific agonist of CAR2. A meclizine derived pharmacophore was utilized in a ligand-based virtual screening and identified two novel CAR2 agonists from the NCI chemical database. The results of this dissertation will aid in the development of better models of human CAR activation, give a more complete understanding of the interaction of CAR with xenobiotics, yield novel insight into potential mechanisms of phthalate toxicity and provide the foundation for future studies into the physiologic functions of alternatively spliced variants of CAR. Advisors/Committee Members: Curtis John Omiecinski, Dissertation Advisor/Co-Advisor, Curtis John Omiecinski, Committee Chair/Co-Chair, Reka Z Albert, Committee Member, Adam Bleier Glick, Committee Member, John Patrick Vanden Heuvel, Committee Member.

Subjects/Keywords: phthalates; alternative splicing; constitutive androstane receptor; drug and xenobiotic metabolism; meclizine; nuclear receptors; gene induction

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

De Keyser, J. G. (2009). ALTERNATIVE SPLICING OF THE HUMAN CONSTITUTIVE ANDROSTANE RECEPTOR GENE CREATES RECEPTORS WITH UNIQUE FUNCTION AND LIGAND SPECIFICITY . (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/9350

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

De Keyser, Joshua Gordon. “ALTERNATIVE SPLICING OF THE HUMAN CONSTITUTIVE ANDROSTANE RECEPTOR GENE CREATES RECEPTORS WITH UNIQUE FUNCTION AND LIGAND SPECIFICITY .” 2009. Thesis, Penn State University. Accessed March 04, 2021. https://submit-etda.libraries.psu.edu/catalog/9350.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

De Keyser, Joshua Gordon. “ALTERNATIVE SPLICING OF THE HUMAN CONSTITUTIVE ANDROSTANE RECEPTOR GENE CREATES RECEPTORS WITH UNIQUE FUNCTION AND LIGAND SPECIFICITY .” 2009. Web. 04 Mar 2021.

Vancouver:

De Keyser JG. ALTERNATIVE SPLICING OF THE HUMAN CONSTITUTIVE ANDROSTANE RECEPTOR GENE CREATES RECEPTORS WITH UNIQUE FUNCTION AND LIGAND SPECIFICITY . [Internet] [Thesis]. Penn State University; 2009. [cited 2021 Mar 04]. Available from: https://submit-etda.libraries.psu.edu/catalog/9350.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

De Keyser JG. ALTERNATIVE SPLICING OF THE HUMAN CONSTITUTIVE ANDROSTANE RECEPTOR GENE CREATES RECEPTORS WITH UNIQUE FUNCTION AND LIGAND SPECIFICITY . [Thesis]. Penn State University; 2009. Available from: https://submit-etda.libraries.psu.edu/catalog/9350

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

12. Touloupi, Katerina. Regulation of aldehyde dehydrogenases by nuclear receptors CAR and PXR in rats genetically predetermined in response to phenobarbital.

Degree: 2015, University of Ioannina; Πανεπιστήμιο Ιωαννίνων

URL: http://hdl.handle.net/10442/hedi/43024

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The magnitude of the genes belonging to the ALDH superfamily in organism’s welfare andespecially their protection against xenobiotics, as well as the accumulating evidence that… (more)

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The magnitude of the genes belonging to the ALDH superfamily in organism’s welfare andespecially their protection against xenobiotics, as well as the accumulating evidence that indicateinvolvement of nuclear receptors in regulation of many genes including ALDHs, has excited our interestin unraveling the potential role of CAR and PXR in mediation/regulation of ALDH1As subfamily ofgenes, utilizing the unique experimental model of Wistar/Af/Han/Mol/Kuo/Io rats. Specifically, the tworat strains used in this study were either responsive (RR) or non-responsive (rr) to induction ofALDH1A genes after administration of PB (Phenobarbital) or other PB-type inducers.The apparent difference of ALDH1As induction between the two strains, both at basal levelsand after treatment with PB or PCN, which was detected with protein immunoprecipitation experiments,was further investigated at mRNA levels of expression. The results revealed that the remarkabledifference was attributed to the complete absence of ALDH1A7 expression in rr strain. Furthermore, astriking up-regulation of the gene was observed in RR rats in the presence the above drugs, which act as selective agonists for the nuclear receptors CAR and PXR. Concurrently, expression of ALDH1A1gene was only slightly higher in rr rats, compared to respective expression levels in RR animals.Supportive evidence to our findings was displayed in experiments of ontogenesis with liver samplesderived from neonates and corresponding in vitro studies in primary hepatocyte cultures.The nuclear translocation of CAR and PXR upon treatment with their selective agonists wasevident in both rat strains and also time- and dose-dependent, however their potential gene activationhad to be further tested by studying the induction of their well-studied target genes; CYP2B1 andCYP3A1, respectively.Focusing on the tremendous difference of ALDH1A7 expression between the strains and theuncontest effect of drugs in transcription regulation, we performed reporter gene assays with variousdeletion constructs of RR-ALDH1A7 and rr-ALDH1A7 promoters, as well as chromatinimmunoprecipitation assays on the same promoter regions. Interestingly, our results indicated RRALDH1A7as an active promoter highly-upregulated in response to PB administration, which is instrong contrast to the barely active rr-ALDH1A7. Although the proximal promoter is the essentialregion for turning on gene transcription, we nominated a region of the RR-ALDH1A7 promoter between-1566 to -452,which demonstrated highest activation potential.CAR was emerged as a substantial regulator of RR-ALDH1A7 gene activation, especially whenPB or other CAR-activators were administered. In RR-ALDH1A7, CAR was found to bind to the distalpromoter of the gene, serving as enhancer of gene expression, and presumably PXR may also be ableto bind, since the receptors are promiscuous to their binding to targets and cross-talk to each other.

H σπουδαιότητα των ενζύμων που ανήκουν στην υπερ-οικογένεια των αλδεϋδικών αφυδρογονασών (ALDHs) στην ευζωία των οργανισμών και…

Subjects/Keywords: Αλδεϋδικές αφυδρογονάσες 1Α1 και 1Α7; Πυρηνικοί υποδοχείς; Ιδιοσυστατικός υποδοχέας ανδροστενών; Υποδοχέας πρεγνανίου; φαινοβαρβιτάλη; Καρβονιτρίλιο της πρεγνενολόνης; Μετρήσεις γονιδίου αναφοράς; Δοκιμασίες ανοσοκαθίζησης χρωματίνης; Aldehyde dehydrogenases (ALDHs) 1A1 and 1A7; Nuclear receptors; Constitutive androstane receptor (CAR);

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Touloupi, K. (2015). Regulation of aldehyde dehydrogenases by nuclear receptors CAR and PXR in rats genetically predetermined in response to phenobarbital. (Thesis). University of Ioannina; Πανεπιστήμιο Ιωαννίνων. Retrieved from http://hdl.handle.net/10442/hedi/43024

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Touloupi, Katerina. “Regulation of aldehyde dehydrogenases by nuclear receptors CAR and PXR in rats genetically predetermined in response to phenobarbital.” 2015. Thesis, University of Ioannina; Πανεπιστήμιο Ιωαννίνων. Accessed March 04, 2021. http://hdl.handle.net/10442/hedi/43024.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Touloupi, Katerina. “Regulation of aldehyde dehydrogenases by nuclear receptors CAR and PXR in rats genetically predetermined in response to phenobarbital.” 2015. Web. 04 Mar 2021.

Vancouver:

Touloupi K. Regulation of aldehyde dehydrogenases by nuclear receptors CAR and PXR in rats genetically predetermined in response to phenobarbital. [Internet] [Thesis]. University of Ioannina; Πανεπιστήμιο Ιωαννίνων; 2015. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10442/hedi/43024.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Touloupi K. Regulation of aldehyde dehydrogenases by nuclear receptors CAR and PXR in rats genetically predetermined in response to phenobarbital. [Thesis]. University of Ioannina; Πανεπιστήμιο Ιωαννίνων; 2015. Available from: http://hdl.handle.net/10442/hedi/43024

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Queensland

13. Hu, Hao. Transcriptional regulation of human stress responsive cytochrome P450 2A6 (CYP2A6) by p53.

Degree: School of Medicine, 2016, University of Queensland

URL: http://espace.library.uq.edu.au/view/UQ:405743

Subjects/Keywords: Cytochrome P450 2A6 (CYP2A6); Bilirubin (BR); Haem oxygenase1 (HMOX1); Benzo[α]pyrene (BaP); Nuclear factor erythroid 2-like 2 (Nrf-2); Tumour suppressor p53; Constitutive androstane receptor (CAR); CEBP α; Octamer-1 (Oct-1); Hepatocyte nuclear factor-4α (HNF-4α); 060107 Enzymes; 060111 Signal Transduction; 060199 Biochemistry and Cell Biology not elsewhere classified

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Hu, H. (2016). Transcriptional regulation of human stress responsive cytochrome P450 2A6 (CYP2A6) by p53. (Thesis). University of Queensland. Retrieved from http://espace.library.uq.edu.au/view/UQ:405743

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Hu, Hao. “Transcriptional regulation of human stress responsive cytochrome P450 2A6 (CYP2A6) by p53.” 2016. Thesis, University of Queensland. Accessed March 04, 2021. http://espace.library.uq.edu.au/view/UQ:405743.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Hu, Hao. “Transcriptional regulation of human stress responsive cytochrome P450 2A6 (CYP2A6) by p53.” 2016. Web. 04 Mar 2021.

Vancouver:

Hu H. Transcriptional regulation of human stress responsive cytochrome P450 2A6 (CYP2A6) by p53. [Internet] [Thesis]. University of Queensland; 2016. [cited 2021 Mar 04]. Available from: http://espace.library.uq.edu.au/view/UQ:405743.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hu H. Transcriptional regulation of human stress responsive cytochrome P450 2A6 (CYP2A6) by p53. [Thesis]. University of Queensland; 2016. Available from: http://espace.library.uq.edu.au/view/UQ:405743

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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