subject:(Intestinal L cells)

Georgia Tech

1. Tiernan, Aubrey Rose. Development of a pancreatic substitute based on genetically engineered intestinal endocrine cells.

Degree: PhD, Chemical and Biomolecular Engineering, 2014, Georgia Tech

URL: http://hdl.handle.net/1853/53987

► Cell-based insulin therapies can potentially improve glycemic regulation in insulin dependent diabetes patients and thus help reduce secondary complications. The long-term goal of our work… (more)

▼ Cell-based insulin therapies can potentially improve glycemic regulation in insulin dependent diabetes patients and thus help reduce secondary complications. The long-term goal of our work is to engineer autologous insulin-secreting intestinal endocrine cells as a non-beta cell approach to alleviate donor cell shortage and immune rejection issues associated with islet transplantation. These cells have been chosen for their endogenous similarity to beta cells, but generating cell constructs with sufficient insulin secretion for therapeutic effect has proven challenging. Previous work in our lab showed that a tissue engineered pancreatic substitute (TEPS) based on an engineered insulin-secreting L cell line, GLUTag-INS, was insufficient in affecting blood glucose levels in streptozotocin-induced diabetic mice, but promising since human insulin was detected in the blood. The objective of this project was therefore to fabricate an improved TEPS based on GLUTag-INS cells and evaluate its suitability as a standalone diabetes therapy. To achieve this objective, the following specific aims were (1) to investigate gene incorporation as a strategy to enhance recombinant insulin secretion from GLUTag-INS cells; (2) to develop and characterize a TEPS in vitro based on a microcapsule system containing improved GLUTag-INS cells with bioluminescence monitoring capability; and (3) to assess therapeutic efficacy of the graft in a diabetic, immune-competent mouse model and use bioluminescence monitoring to elucidate in vivo transplant behavior. This thesis therefore reports on the progression of studies from the genetic and molecular levels for improved insulin secretion per-cell, to the tissue level for enhanced secretion per-graft, and lastly to the preclinical level for therapeutic assessment in a diabetic mouse model. Advisors/Committee Members: Sambanis, Athanassios (advisor), Koros, William (committee member), Le Doux, Joe (committee member), Thule, Peter M. (committee member), Champion, Julie A. (committee member).

Subjects/Keywords: Diabetes; Bioluminescence; Intestinal L cells; Pancreatic substitute; Cell encapsulation

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

APA (6^th Edition):

Tiernan, A. R. (2014). Development of a pancreatic substitute based on genetically engineered intestinal endocrine cells. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/53987

Chicago Manual of Style (16^th Edition):

Tiernan, Aubrey Rose. “Development of a pancreatic substitute based on genetically engineered intestinal endocrine cells.” 2014. Doctoral Dissertation, Georgia Tech. Accessed February 25, 2021. http://hdl.handle.net/1853/53987.

MLA Handbook (7^th Edition):

Tiernan, Aubrey Rose. “Development of a pancreatic substitute based on genetically engineered intestinal endocrine cells.” 2014. Web. 25 Feb 2021.

Vancouver:

Tiernan AR. Development of a pancreatic substitute based on genetically engineered intestinal endocrine cells. [Internet] [Doctoral dissertation]. Georgia Tech; 2014. [cited 2021 Feb 25]. Available from: http://hdl.handle.net/1853/53987.

Council of Science Editors:

Tiernan AR. Development of a pancreatic substitute based on genetically engineered intestinal endocrine cells. [Doctoral Dissertation]. Georgia Tech; 2014. Available from: http://hdl.handle.net/1853/53987

University of Cambridge

2. Billing, Lawrence. Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations.

Degree: PhD, 2019, University of Cambridge

URL: https://www.repository.cam.ac.uk/handle/1810/290641

► Enteroendocrine cells (EECs) are chemosensitive cells of the gastrointestinal epithelium that exert a wide range of physiological effects via production and secretion of hormones in… (more)

▼ Enteroendocrine cells (EECs) are chemosensitive cells of the gastrointestinal epithelium that exert a wide range of physiological effects via production and secretion of hormones in response to ingested nutrients, bacterial metabolites and systemic signals. Glucagon-like peptide-1 (GLP-1) is one such hormone secreted from so-called L-cells found in both the small and large intestines. GLP-1 exerts an anorexigenic effect and together with glucose- dependent insulinotropic polypeptide (GIP), restores postprandial normoglycaemia through the incretin effect. These effects are exploited by GLP-1 analogues in the treatment of type 2 diabetes. GLP-1 may also contribute to weight-loss and remission of type 2 diabetes following bariatric surgery which increases postprandial GLP-1 excursions. Here we investigated stimulus secretion coupling in L-cells. A novel 2D culture system from murine small intestinal organoids was established as an in vitro model. This was used to characterise synergistic stimulation of GLP-1 secretion in response to concomitant stimulation by bile acids through the Gs-protein coupled receptor GPBAR1 and free fatty acids through the Gq-coupled receptor FFAR1. Roughly half of colonic, but not small intestinal, L-cells co-produce the orexigenic peptide insulin-like peptide 5 (INSL5). This hitherto poorly examined subpopulation of L-cells was characterised through transcriptomic analysis, intracellular calcium imaging (using a novel GCaMP6F-based transgenic mouse model), LC/MS peptide quantification and 3D super resolution microscopy (3D-SIM). Based on the observed prevalent co-storage of GLP-1 and INSL5 in secretory vesicles and similar secretory responses of both hormones to a range of different stimuli strengths (including short chain fatty acids, angiotensin II and arginine vasopressin (AVP)) it was concluded that GLP-1 and INSL5 are co-secreted, rather than being selectively recruited by different stimuli. To further characterise the diversity of colonic EECs, single cell RNA-sequencing (scRNA-seq) was performed on cells isolated from mice with a pan-EEC fluorescent marker (NeuroD1- Cre:Rosa26-EYFP). This illustrated that INSL5-producing L-cells form one of two transcriptomically distinct subpopulations of L-cells in the murine colon, with the other distinguished by expression of neurotensin (Nts). Another major EEC subpopulation, enterochromaffin (EC) cells could be split into three groups, mechanosensitive and pro- inflammatory EC cells distinguished by Piezo2 and Tac1 expression, respectively and a third Sct-expressing group. Immunofluorescent labelling and RT-qPCR analysis revealed that the Nts-expressing and Insl5-expressing L-cell subpopulations are proximally and distally enriched in the murine colon, respectively. In primary cultures, angiotensin II and AVP stimulated INSL5, GLP-1 and PYY but not NTS secretion, correlating with selective expression profiles of the cognate receptors in the L-cell subpopulations. In summary, the work presented suggests that different L-cell subpopulations…

Subjects/Keywords: INSL5; GLP-1; Enteroendocrine cells; Intestinal Organoids; scRNA-seq; L-cells; Gut peptides; Diabetes; Obesity; Colon; Small intestine; Neurotensin

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

APA (6^th Edition):

Billing, L. (2019). Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations. (Doctoral Dissertation). University of Cambridge. Retrieved from https://www.repository.cam.ac.uk/handle/1810/290641

Chicago Manual of Style (16^th Edition):

Billing, Lawrence. “Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations.” 2019. Doctoral Dissertation, University of Cambridge. Accessed February 25, 2021. https://www.repository.cam.ac.uk/handle/1810/290641.

MLA Handbook (7^th Edition):

Billing, Lawrence. “Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations.” 2019. Web. 25 Feb 2021.

Vancouver:

Billing L. Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations. [Internet] [Doctoral dissertation]. University of Cambridge; 2019. [cited 2021 Feb 25]. Available from: https://www.repository.cam.ac.uk/handle/1810/290641.

Council of Science Editors:

Billing L. Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations. [Doctoral Dissertation]. University of Cambridge; 2019. Available from: https://www.repository.cam.ac.uk/handle/1810/290641

University of Cambridge

3. Billing, Lawrence. Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations.

Degree: PhD, 2019, University of Cambridge

URL: https://doi.org/10.17863/CAM.37850 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.774620

► Enteroendocrine cells (EECs) are chemosensitive cells of the gastrointestinal epithelium that exert a wide range of physiological effects via production and secretion of hormones in… (more)

▼ Enteroendocrine cells (EECs) are chemosensitive cells of the gastrointestinal epithelium that exert a wide range of physiological effects via production and secretion of hormones in response to ingested nutrients, bacterial metabolites and systemic signals. Glucagon-like peptide-1 (GLP-1) is one such hormone secreted from so-called L-cells found in both the small and large intestines. GLP-1 exerts an anorexigenic effect and together with glucose- dependent insulinotropic polypeptide (GIP), restores postprandial normoglycaemia through the incretin effect. These effects are exploited by GLP-1 analogues in the treatment of type 2 diabetes. GLP-1 may also contribute to weight-loss and remission of type 2 diabetes following bariatric surgery which increases postprandial GLP-1 excursions. Here we investigated stimulus secretion coupling in L-cells. A novel 2D culture system from murine small intestinal organoids was established as an in vitro model. This was used to characterise synergistic stimulation of GLP-1 secretion in response to concomitant stimulation by bile acids through the Gs-protein coupled receptor GPBAR1 and free fatty acids through the Gq-coupled receptor FFAR1. Roughly half of colonic, but not small intestinal, L-cells co-produce the orexigenic peptide insulin-like peptide 5 (INSL5). This hitherto poorly examined subpopulation of L-cells was characterised through transcriptomic analysis, intracellular calcium imaging (using a novel GCaMP6F-based transgenic mouse model), LC/MS peptide quantification and 3D super resolution microscopy (3D-SIM). Based on the observed prevalent co-storage of GLP-1 and INSL5 in secretory vesicles and similar secretory responses of both hormones to a range of different stimuli strengths (including short chain fatty acids, angiotensin II and arginine vasopressin (AVP)) it was concluded that GLP-1 and INSL5 are co-secreted, rather than being selectively recruited by different stimuli. To further characterise the diversity of colonic EECs, single cell RNA-sequencing (scRNA-seq) was performed on cells isolated from mice with a pan-EEC fluorescent marker (NeuroD1- Cre:Rosa26-EYFP). This illustrated that INSL5-producing L-cells form one of two transcriptomically distinct subpopulations of L-cells in the murine colon, with the other distinguished by expression of neurotensin (Nts). Another major EEC subpopulation, enterochromaffin (EC) cells could be split into three groups, mechanosensitive and pro- inflammatory EC cells distinguished by Piezo2 and Tac1 expression, respectively and a third Sct-expressing group. Immunofluorescent labelling and RT-qPCR analysis revealed that the Nts-expressing and Insl5-expressing L-cell subpopulations are proximally and distally enriched in the murine colon, respectively. In primary cultures, angiotensin II and AVP stimulated INSL5, GLP-1 and PYY but not NTS secretion, correlating with selective expression profiles of the cognate receptors in the L-cell subpopulations. In summary, the work presented suggests that different L-cell subpopulations exist…

Subjects/Keywords: INSL5; GLP-1; Enteroendocrine cells; Intestinal Organoids; scRNA-seq; L-cells; Gut peptides; Diabetes; Obesity; Colon; Small intestine; Neurotensin

Record Details Similar Records Cite « Share

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

APA (6^th Edition):

Billing, L. (2019). Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations. (Doctoral Dissertation). University of Cambridge. Retrieved from https://doi.org/10.17863/CAM.37850 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.774620

Chicago Manual of Style (16^th Edition):

Billing, Lawrence. “Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations.” 2019. Doctoral Dissertation, University of Cambridge. Accessed February 25, 2021. https://doi.org/10.17863/CAM.37850 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.774620.

MLA Handbook (7^th Edition):

Billing, Lawrence. “Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations.” 2019. Web. 25 Feb 2021.

Vancouver:

Billing L. Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations. [Internet] [Doctoral dissertation]. University of Cambridge; 2019. [cited 2021 Feb 25]. Available from: https://doi.org/10.17863/CAM.37850 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.774620.

Council of Science Editors:

Billing L. Characterisation of L-cell secretory mechanisms and colonic enteroendocrine cell subpopulations. [Doctoral Dissertation]. University of Cambridge; 2019. Available from: https://doi.org/10.17863/CAM.37850 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.774620

4. Ducastel, Sarah. Le récepteur nucléaire FXR dans les cellules L entéroendocrines : régulateur de la réponse aux acides gras à chaîne courte, métabolites du microbiote intestinal : The nuclear receptor FXR in enteroendocrine L cells : regulator of the response to short-chain fatty acids, gut microbiota-metabolites.

Degree: Docteur es, Biochimie, biologie cellulaire et moléculaire, physiologie et nutrition, 2019, Université Lille II – Droit et Santé

URL: http://www.theses.fr/2019LIL2S022

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Le contrôle de l’homéostasie du glucose est le résultat d’un dialogue étroit entre les différents organes métaboliques par l’intermédiaire de messages nerveux et hormonaux. Parmi… (more)

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Le contrôle de l’homéostasie du glucose est le résultat d’un dialogue étroit entre les différents organes métaboliques par l’intermédiaire de messages nerveux et hormonaux. Parmi les mécanismes de régulation, l’incrétine GLP-1 (Glucagon-Like Peptide-1), produite et sécrétée par les cellules entéroendocrines de type L dans l’intestin en réponse à la prise alimentaire, potentialise la sécrétion d’insuline par le pancréas. Au début de ma thèse, j’ai participé aux travaux de l’équipe qui ont permis de montrer que l’activation du récepteur nucléaire Farnesoid X Receptor (FXR) diminue la production et la sécrétion de GLP-1 en réponse au glucose. Cependant, comme il existe de nombreux autres stimuli de la sécrétion de GLP-1, nous avons ensuite cherché à savoir si FXR régule également d’autres voies de sécrétion de GLP-1. En particulier, le microbiote intestinal participe au contrôle de l'homéostasie énergétique par la fermentation des fibres alimentaires, produisant dans le colon des acides gras à chaîne courte (SCFAs) qui favorisent la sécrétion de GLP-1 en se liant à leurs récepteurs membranaires FFAR2 et FFAR3. L’objectif suivant de mes travaux de thèse a donc été d’étudier le rôle de FXR dans la réponse des cellules L du colon aux SCFAs.La sécrétion de GLP-1 en réponse aux SCFAs a été évaluée ex vivo dans des explants intestinaux de souris traitées avec le GW4064, agoniste synthétique de FXR, dans des colonoïdes murins issus de souris WT et FXR KO, in vitro dans les cellules L murines GLUTag et humaines NCI-H716 activées avec le GW4064 et in vivo chez des souris WT et FXR KO après supplémentation en prébiotiques(fructanes de type inuline) pour augmenter la production de SCFAs dans le colon. L’expression des récepteurs aux SCFA FFAR2 et FFAR3 a également été examinée dans ces différents modèles et la voie de signalisation intracellulaire de type Gαq de FFAR2 a été évaluée in vitro.La sécrétion de GLP-1 induite par les SCFAs est inhibée dans les explants de côlon de souris traitées par le GW4064 et améliorée dans les colonoïdes FXR KO. L’activation in vitro de FXR inhibela sécrétion de GLP-1 en réponse aux SCFAs et aux ligands synthétiques de FFAR2, principalement en diminuant l’expression de FFAR2 et sa signalisation intracellulaire de type Gαq. Les souris FXR KO présentent une augmentation de l’expression de FFAR2 dans le côlon et des taux plasmatiques de GLP-1 augmentés lors de la supplémentation en prébiotiques.L’ensemble de mes résultats de thèse montrent donc que l’inhibition de FXR augmente la sécrétion de GLP-1 par les cellules L entéroendocrines en réponse au glucose et aux métabolites du microbiote intestinal, les SCFAs. La combinaison de l’utilisation d’antagonistes ou de dé-activateurs de FXR dans l’intestin avec une supplémentation en prébiotiques peut ainsi être une approche thérapeutique prometteuse pour stimuler l’axe incrétine dans le traitement du diabète de type 2 et des maladies du foie gras non alcoolique telles que la NASH (Non Alcoholic SteatoHepatitis).

The control of glucose homeostasis is the…

Advisors/Committee Members: Lestavel, Sophie (thesis director).

Subjects/Keywords: Cellules L; Instestins; Microbiote intestinal; Entéro-hormones; Acides gras à chaîne courte; FXR; FFAR2; FFAR3; Diabète de type 2; L cells; Intestine; Intestinal microbiota; Type 2 diabetes; Prebiotic; FXR; FFAR2; FFAR3

Record Details Similar Records Cite « Share

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

APA (6^th Edition):

Ducastel, S. (2019). Le récepteur nucléaire FXR dans les cellules L entéroendocrines : régulateur de la réponse aux acides gras à chaîne courte, métabolites du microbiote intestinal : The nuclear receptor FXR in enteroendocrine L cells : regulator of the response to short-chain fatty acids, gut microbiota-metabolites. (Doctoral Dissertation). Université Lille II – Droit et Santé. Retrieved from http://www.theses.fr/2019LIL2S022

Chicago Manual of Style (16^th Edition):

Ducastel, Sarah. “Le récepteur nucléaire FXR dans les cellules L entéroendocrines : régulateur de la réponse aux acides gras à chaîne courte, métabolites du microbiote intestinal : The nuclear receptor FXR in enteroendocrine L cells : regulator of the response to short-chain fatty acids, gut microbiota-metabolites.” 2019. Doctoral Dissertation, Université Lille II – Droit et Santé. Accessed February 25, 2021. http://www.theses.fr/2019LIL2S022.

MLA Handbook (7^th Edition):

Ducastel, Sarah. “Le récepteur nucléaire FXR dans les cellules L entéroendocrines : régulateur de la réponse aux acides gras à chaîne courte, métabolites du microbiote intestinal : The nuclear receptor FXR in enteroendocrine L cells : regulator of the response to short-chain fatty acids, gut microbiota-metabolites.” 2019. Web. 25 Feb 2021.

Vancouver:

Ducastel S. Le récepteur nucléaire FXR dans les cellules L entéroendocrines : régulateur de la réponse aux acides gras à chaîne courte, métabolites du microbiote intestinal : The nuclear receptor FXR in enteroendocrine L cells : regulator of the response to short-chain fatty acids, gut microbiota-metabolites. [Internet] [Doctoral dissertation]. Université Lille II – Droit et Santé 2019. [cited 2021 Feb 25]. Available from: http://www.theses.fr/2019LIL2S022.

Council of Science Editors:

Ducastel S. Le récepteur nucléaire FXR dans les cellules L entéroendocrines : régulateur de la réponse aux acides gras à chaîne courte, métabolites du microbiote intestinal : The nuclear receptor FXR in enteroendocrine L cells : regulator of the response to short-chain fatty acids, gut microbiota-metabolites. [Doctoral Dissertation]. Université Lille II – Droit et Santé 2019. Available from: http://www.theses.fr/2019LIL2S022

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Open Access Theses and Dissertations