Analisamos a ação da liraglutida na flora intestinal e perda de peso de dois modelos de obesidade: por dieta hiperlipidica (HFD) e obesidade genética (ob/ob). Os modelos foram tratados com o fármaco durante duas semanas. Perfis metabólicos foram feitos por meio de testes glicêmicos e insulínicos, histologia do fígado, região cecal e coxins gordurosos, ingestão alimentar, peso corporal e metagenômica do conteúdo cecal. O tratamento induziu perda de peso com melhora dos níveis glicêmicos e redução da inflamação na região cecal e do fígado e foi capaz de reduzir o acúmulo de gordura hepática promovendo a redução da EHNA. A metagenômica mostrou mudança taxonômica geral, bem como a abundância relativa de bactérias envolvidas com peso e controle glicêmico:redução de Proteobacterias e aumento de Akkermansia muciniphila. Apresentamos evidências do fármaco revertendo DGHNA/EHNA e a perda de peso associados às mudanças da microbiota. Sugerimos uma lista de alvos bacterianos que podem interferir no metabolismo energético para o controle clinico de doenças metabólicas. / The study analyzed the effects of liraglutide on gut microbiota and weight-loss in two obesity model: induced by high fat diet (HFD) and genetic obese mice (ob/ob). Models were treated with liraglutide for two weeks. Metabolic profiles were measured by glycemic and insulin test, histological liver, cecal region and fat pad morphologies, food intake, body weight and metagenomic of cecal contents. The treatment induced weight-loss, improvement of glycemic parameters and reduction of inflammatory cells in the cecum and the liver and reduced fat accumulation in liver reverting NASH. The metagenomic showed a general changed in taxonomic structure as well the relative abundance of weight-relevant:reduction of Proteobacteria and increases of Akkermansia muciniphila. We showed evidences that liraglutide leads to improvement of NASH and weight loss associated with changes in microbiota. Moreover, by the profile of the gut microbiota, we present a bacterial target list that may affect energetic metabolism inducing a metabolic clinical controlled profile.

Este trabalho visa investigar a resposta sorológica para glicolipoproteína (GLP) de leptospiras com a finalidade de padronizar o uso deste antígeno em testes sorológicos para o diagnóstico da leptospirose humana. Dentre as proteínas envolvidas na patogenicidade das leptospiras, a GLP ainda não foi estudada quanto a imunogenicidade e quanto ao seu emprego como antígeno na detecção de anticorpos específicos. Assim, dot-ELISA para detecção de anticorpos IgG e IgM, com o emprego de GLP de leptospiras patogênica e não patogênica, foi padronizado. Foram testadas amostras pareadas de soros de 90 pacientes com leptospirose confirmada sorologicamente por MAT, sendo as primeiras amostras colhidas na fase aguda da doença e as segundas amostras após 10 a 15 dias. Foram testadas também amostras únicas de 30 pacientes de diferentes patologias, que apresentaram resultados negativos no MAT, pertencentes ao grupo controle. A detecção de anticorpos IgG não mostrou resultados satisfatórios, tendo sido, o seu estudo, descontinuado. Os resultados do dot-ELISA IgM mostraram sensibilidade de 100% nas amostras colhidas após soroconversão no MAT e a precocidade de detecção foi demonstrada pela alta positividade nas amostras colhidas na fase aguda da doença (76,6% para dot-ELISA com antígeno de Leptospira interrogans sorovar Copenhageni e 90% com antígeno de Leptospira biflexa sorovar Patoc). A especificidade foi alta (96,6%), porém o dot-ELISA utilizando ambos os antígenos apresentou 3,3% de resultados falso-positivos. Este estudo demonstrou a importância da resposta imune humoral ao antígeno GLP de leptospiras. A utilização da GLP, no teste dot-ELISA para detecção de anticorpos IgM permitiu realizar o diagnóstico sorológico de forma simples, rápida e com alta eficiência diagnóstica. / The aim of this work was the study of serologic response against leptospira glycolipoprotein (GLP) for the purpose of standardizing its use as an antigen on serological tests to diagnose human leptospirosis. Among the proteins involved in the pathogenicity, GLP is yet to be studied regarding its immunogenicity and its use as an antigen in the detection of specific antibodies. That led to our standardization of dot-ELISA for detecting IgG and IgM antibodies, using GLP extracted from either pathogenic Leptospira interrogans serovar Copenhageni or nonpathogenic Leptospira biflexa serovar Patoc. Paired serum samples were taken from 90 patients with serologically confirmed leptospirosis, by MAT, with the first samples collected on the disease\'s acute phase and the second samples after a period of 10 to 15 days. We also tested single samples taken from 30 patients with other diseases, MAT negative, belonging to the control group. Detection rates for IgG antibodies were unsatisfactory, so the study for that use was discontinued. The dot-ELISA IgM results yielded 100% sensitivity on the samples taken after MAT seroconversion. The early detection pattern was evidenced by the high positivity rate on the samples taken during the disease\'s acute phase (76,6% dot-ELISA using Leptospira interrogans serovar Copenhageni antigen and 90% using Leptospira biflexa sorovar Patoc antigen). Specificity rates were high (96.6%), although a 3.3% rate of false-positive results was observed for dot-ELISA using both antigens. The present study revealed the importance of the humoral immune response against the GLP antigen. The use of GLP, on the dot-ELISA test for IgM antibodies afforded a simple, quick and effective diagnosis.

Les acides biliaires sont depuis longtemps connus pour leur propriété d’agents solubilisant des graisses et des vitamines liposolubles, permettant ainsi une absorption efficace de ces nutriments lors de la digestion. Depuis les années 2000, plusieurs équipes ont montré que ces molécules étaient également dotées de propriétés de signalisation, en particulier via l’activation de deux récepteurs : le récepteur nucléaire FXR, et le récepteur membranaire TGR5. Le récepteur TGR5 est exprimé dans de très nombreux tissus, dont les muscles lisses et squelettiques, le tissu adipeux brun, la vésicule biliaire, mais aussi certaines cellules immunitaires et certaines populations cellulaires intestinales telles que les cellules entéroendocrine L. Selon le tissu étudié, l’activation de TGR5 peut être suivie de nombreux effets biologiques. En particulier, au niveau intestinal, l’activation de ce récepteur stimule la sécrétion de l’hormone incrétine GLP-1.Les hormones incrétines sont impliquées dans la régulation de la glycémie, en particulier dans la phase postprandiale, où elles concourent à potentialiser l’action de l’insuline, hormone hypoglycémiante majeure. Or, dans un contexte de diabète, et en particulier de diabète de type 2, l’organisme est devenu moins sensible à l’insuline, ce qui se traduit par un défaut de gestion de la glycémie, pouvant entrainer à terme des complications graves, telles que des amputations, une cécité, ou encore des problèmes cardiovasculaires. La prévalence et l’incidence de cette pathologie ont conduit l’OMS à la considérer comme la première épidémie d’origine non-infectieuse, ce qui illustre son impact sur la santé publique et le besoin médical constant qu’elle génère.Dans ce contexte, TGR5 apparait comme cible thérapeutique potentielle attrayante, de par l’effet GLP-1 sécrétagogue consécutif à son activation. En effet, parmi les thérapies antidiabétiques, deux classes de molécules basent leur efficacité sur une augmentation de la signalisation de la voie incrétine : les incrétinopotentiateurs (inhibiteurs de la DDP4, enzyme responsable de la faible demi-vie du GLP-1) et les incrétinomimétiques (agonistes synthétiques du récepteur au GLP-1). Récemment, cette dernière classe a également fait son apparition dans l’arsenal thérapeutique de l’obésité, confirmant l’intérêt de cette voie de signalisation dans les pathologies issues d’un désordre métabolique. L’obtention de composés GLP-1 sécrétagogues s’avère ainsi prometteuse et représente une approche complémentaire aux deux autres classes.L’objectif de ce travail était donc d’obtenir des agonistes puissants, sélectifs et originaux du récepteur TGR5. Afin de diminuer les risques d’effets indésirables, on-target ou off-target, nous avons choisi de profiter de la localisation intestinale de notre cible d’intérêt en concevant nos composés de manière à limiter l’exposition au seul tractus gastro-intestinal, en limitant leur absorption. Ainsi, nous avons cherché à obtenir des composés non systémiques GLP-1 sécrétagogues.La stratégie employée pour aboutir à ces composés a été le développement de molécules chimériques constituées d’une partie agoniste de TGR5, le pharmacophore, liée à un groupement permettant de limiter la perméabilité membranaire et donc l’absorption intestinale, le kinétophore. Après avoir optimisé la partie pharmacophore et identifié une position permettant l’ajout de différents types de kinétophores sans impact majeur sur l’activité du composé, nous avons pu obtenir plusieurs agonistes de TGR5 puissants, originaux, et dotés d’une très faible perméabilité membranaire. L’étude in vivo de ces molécules a ensuite permis de valider d’une part leur activité GLP-1 sécrétagogue, et d’autre part leur faible exposition systémique. Enfin, l’évaluation du potentiel thérapeutique d’un des meilleurs composés dans des modèles murins de diabète a récemment pu être initiée. / Bile acids have long been known as lipid solubilizing agents, enabling efficient absorption of nutrients and vitamins during digestion. Since 2000, several teams have demonstrated the signaling properties of these molecules, especially through the activation of two receptors : the nuclear receptor FXR and the membrane receptor TGR5.The TGR5 receptor is expressed in various tissues, such as smooth and skeletal muscles, brown adipose tissue, gallbladder, but also on some immune or intestinal cell lines such as the enteroendocrine L cells. Depending on the studied tissue, TGR5 activation can trigger various biological effects. In the intestine, its activation can stimulate the secretion of an incretin hormone, the GLP-1.Incretin hormones play a role in glycaemia regulation, especially during the postprandial phase during which they potentiate the action of the insulin, the main hypoglycemic hormone. Diabetes mellitus correspond to a decreased response of the organism to insulin signaling. This leads to a default in the glycaemia handling that can lead to serious complications, such as amputation, blindness, or cardiovascular problems. Prevalence and incidence of this disease have lead the WHO to define diabetes as the first non-infectious epidemic, illustrating its impact on public health and the constant need for new therapeutic opportunities.In this context, TGR5 appears as an appealing potential therapeutic target, especially because of the GLP-1 secretagogue effect triggered by its activation. Indeed, among the antidiabetic therapeutic options, two classes of drugs work by increasing the incretin signaling: the incretinopotentiators (inhibitors of the DPP4, which is the enzyme responsible for the very short half-life of GLP-1), and the incretinomimetics (synthetic agonists of the GLP-1 receptor). Recently, this last class has also been approved to treat obesity. This demonstrates the interest of this signaling pathway in the treatment of metabolic disorders. Hence, GLP-1 secretagogue compounds may prove to be an interesting approach, and could complement the two other classes.The aim of this work was then to obtain potent, selective and original agonists of the TGR5 receptor. In order to decrease the risk of on-target and off-target effects, we decided to take advantage of the intestinal localization of our target by designing compounds that would only expose the gastro-intestinal tract, by limiting their absorption. Thus, we wanted to obtain non systemic GLP-1 secretagogue compounds.Our strategy was to develop chimeric compounds consisting of a pharmacophore part, which would be a potent and selective agonist of TGR5, linked to a kinetophore part, which would decrease membrane permeability. After having optimized the pharmacophore part and having identified a position where we could link various kinetophore moieties with only weak impact on the activity, we obtained several potent TGR5 agonists with very low membrane permeability. In vivo evaluations of these compounds have validated both their GLP-1 secretagogue activity and their low systemic exposure. In the end, evaluation of our lead compound on mouse model of diabetes was recently started.

<p><strong><p>Abstract</p><em><p>Background and aim:</p>Diabetes mellitus (DM) is a chronic and progressive illness that affects all type of populations and ages. According to World health organization (WHO) by 2030 it will be 366 million people effected world wild. Many new drugs are Glucagon-like peptide-1 (GLP-1) based therapy for treatment of type 2diabetes. GLP-1 is released from the intestinal L-cells, and is a potent stimulator of glucose-dependent insulin secretion. The aim of this study was to investigate the effect of GLP-1 and its stable analogs on cell proliferation of GLP-1 secreting GLUTag cells. <em><p>Material and methods:</p>GluTag cells were incubated for 48h in DMEM medium containing (0.5% fetal bovine serum and 100 IU/ml penicillin and 100 μg/ml streptomycin and 3mM glucose concentration) in the present or absence of the agents. DNA synthesis was measured using 3H- thymidine incorporation and Ki67 antigen staining. Western blot were performed to investigate the present of GLP-1 receptor in GLUTag cells. <em><p>Results/conclusions:</p><p>These results suggest that GLP-1 regulates proliferation of the GLP-1-secreting cell through a feedback mechanism via its receptor. Since serum GLP-1 levels are decreased in type 2 diabetic patients, the effect of GLP-1 on the GLP-1-secreting cell proliferation suggested here provides a novel beneficial long-term effect of the incretin-based drugs in clinical practice i.e. through increase of the GLP-1-secreting cell mass, augmenting the incretin effect. In addition, the feedback mechanism action of GLP-1 reveals a new insight in regulation manner of the L-cell proliferation.</p>GLP-1(7-36) increased cell proliferation in GLUTag cells, an effect which was blocked by the GLP-1 receptor antagonist exendin(9-39). The GLP-1 receptor was expressed in GluTag cells. <em><p>Keywords:</p>Incretin hormone<em>, GLP-1, GLP-1 receptor, Exendin-4, Diabetes </em></em></em></em></em></strong></p>

Abstract Background and aim: Diabetes mellitus (DM) is a chronic and progressive illness that affects all type of populations and ages. According to World health organization (WHO) by 2030 it will be 366 million people effected world wild. Many new drugs are Glucagon-like peptide-1 (GLP-1) based therapy for treatment of type 2diabetes. GLP-1 is released from the intestinal L-cells, and is a potent stimulator of glucose-dependent insulin secretion. The aim of this study was to investigate the effect of GLP-1 and its stable analogs on cell proliferation of GLP-1 secreting GLUTag cells. Material and methods: GluTag cells were incubated for 48h in DMEM medium containing (0.5% fetal bovine serum and 100 IU/ml penicillin and 100 μg/ml streptomycin and 3mM glucose concentration) in the present or absence of the agents. DNA synthesis was measured using 3H- thymidine incorporation and Ki67 antigen staining. Western blot were performed to investigate the present of GLP-1 receptor in GLUTag cells. Results/conclusions: These results suggest that GLP-1 regulates proliferation of the GLP-1-secreting cell through a feedback mechanism via its receptor. Since serum GLP-1 levels are decreased in type 2 diabetic patients, the effect of GLP-1 on the GLP-1-secreting cell proliferation suggested here provides a novel beneficial long-term effect of the incretin-based drugs in clinical practice i.e. through increase of the GLP-1-secreting cell mass, augmenting the incretin effect. In addition, the feedback mechanism action of GLP-1 reveals a new insight in regulation manner of the L-cell proliferation. GLP-1(7-36) increased cell proliferation in GLUTag cells, an effect which was blocked by the GLP-1 receptor antagonist exendin(9-39). The GLP-1 receptor was expressed in GluTag cells. Keywords: Incretin hormone, GLP-1, GLP-1 receptor, Exendin-4, Diabetes

Este trabalho visa investigar a resposta sorológica para glicolipoproteína (GLP) de leptospiras com a finalidade de padronizar o uso deste antígeno em testes sorológicos para o diagnóstico da leptospirose humana. Dentre as proteínas envolvidas na patogenicidade das leptospiras, a GLP ainda não foi estudada quanto a imunogenicidade e quanto ao seu emprego como antígeno na detecção de anticorpos específicos. Assim, dot-ELISA para detecção de anticorpos IgG e IgM, com o emprego de GLP de leptospiras patogênica e não patogênica, foi padronizado. Foram testadas amostras pareadas de soros de 90 pacientes com leptospirose confirmada sorologicamente por MAT, sendo as primeiras amostras colhidas na fase aguda da doença e as segundas amostras após 10 a 15 dias. Foram testadas também amostras únicas de 30 pacientes de diferentes patologias, que apresentaram resultados negativos no MAT, pertencentes ao grupo controle. A detecção de anticorpos IgG não mostrou resultados satisfatórios, tendo sido, o seu estudo, descontinuado. Os resultados do dot-ELISA IgM mostraram sensibilidade de 100% nas amostras colhidas após soroconversão no MAT e a precocidade de detecção foi demonstrada pela alta positividade nas amostras colhidas na fase aguda da doença (76,6% para dot-ELISA com antígeno de Leptospira interrogans sorovar Copenhageni e 90% com antígeno de Leptospira biflexa sorovar Patoc). A especificidade foi alta (96,6%), porém o dot-ELISA utilizando ambos os antígenos apresentou 3,3% de resultados falso-positivos. Este estudo demonstrou a importância da resposta imune humoral ao antígeno GLP de leptospiras. A utilização da GLP, no teste dot-ELISA para detecção de anticorpos IgM permitiu realizar o diagnóstico sorológico de forma simples, rápida e com alta eficiência diagnóstica. / The aim of this work was the study of serologic response against leptospira glycolipoprotein (GLP) for the purpose of standardizing its use as an antigen on serological tests to diagnose human leptospirosis. Among the proteins involved in the pathogenicity, GLP is yet to be studied regarding its immunogenicity and its use as an antigen in the detection of specific antibodies. That led to our standardization of dot-ELISA for detecting IgG and IgM antibodies, using GLP extracted from either pathogenic Leptospira interrogans serovar Copenhageni or nonpathogenic Leptospira biflexa serovar Patoc. Paired serum samples were taken from 90 patients with serologically confirmed leptospirosis, by MAT, with the first samples collected on the disease\'s acute phase and the second samples after a period of 10 to 15 days. We also tested single samples taken from 30 patients with other diseases, MAT negative, belonging to the control group. Detection rates for IgG antibodies were unsatisfactory, so the study for that use was discontinued. The dot-ELISA IgM results yielded 100% sensitivity on the samples taken after MAT seroconversion. The early detection pattern was evidenced by the high positivity rate on the samples taken during the disease\'s acute phase (76,6% dot-ELISA using Leptospira interrogans serovar Copenhageni antigen and 90% using Leptospira biflexa sorovar Patoc antigen). Specificity rates were high (96.6%), although a 3.3% rate of false-positive results was observed for dot-ELISA using both antigens. The present study revealed the importance of the humoral immune response against the GLP antigen. The use of GLP, on the dot-ELISA test for IgM antibodies afforded a simple, quick and effective diagnosis.

Le récepteur membranaire TGR5 (Takeda G Protein-coupled Receptor 5), est un récepteur ubiquitaire sensible aux acides biliaires. Il est exprimé dans de nombreux tissus et organes dont l’intestin (dans les cellules entéroendocrines L), la vésicule biliaire, les muscles lisses et squelettiques, le tissu adipeux brun et dans certaines cellules immunitaires. Des études menées in vitro et in vivo chez l’animal ont montré des effets bénéfiques de l’activation de TGR5 sur l’homéostasie énergétique et glucidique. Il est maintenant communément admis que les effets bénéfiques de TGR5 sur l'homéostasie du glucose sont, au moins en partie, médiés par sa capacité à promouvoir la sécrétion de l'incrétine intestinale glucagon-like peptide-1 (GLP-1) au niveau des cellules entéroendocrines L.Cependant, de récentes expériences ont montré que l’activation de TGR5 par des agonistes systémiques dans des modèles animaux peut induire des effets non souhaités tels qu’une augmentation du volume de la vésicule biliaire, des démangeaisons et des effets cardiovasculaires. Afin de s’affranchir des effets non désirés d’agonistes systémiques de TGR5, le projet s’est orienté vers le développement d’agonistes de TGR5 présentant une distribution tissulaire ciblée et limitée à l’intestin et dont la biodisponibilité orale serait très faible, voire nulle. Nous avons alors émis l’hypothèse qu’une activation de TGR5 limitée à l’épithélium intestinal sans exposition systémique permettrait d’obtenir des effets bénéfiques sur l’homéostasie du glucose via l’effet GLP-1 sécrétagogue, tout en minimisant les effets non souhaités sur d’autres tissus ou organes exprimant TGR5.A partir des études de relations structure-activités obtenues au laboratoire sur une série d’agonistes de TGR5, nous avons conçu des composés chimériques de la façon suivante : le pharmacophore responsable de l’activité sur le récepteur TGR5 est lié via un bras espaceur à des éléments structuraux appelés kinétophores qui ajustent les propriétés physicochimiques et pharmacocinétiques de nos agonistes pour limiter leur absorption intestinale. Ainsi, l’objectif de ce travail était d’obtenir des agonistes non systémiques de TGR5, puissants et originaux, exerçant leur action dans l’intestin afin de générer la preuve de concept in vivo de l’intérêt d’utiliser de tels agonistes dans le traitement du diabète de type 2.Une étude systématique de l’effet de kinétophores variés a été réalisée. Une trentaine de composés ont été synthétisés en 8 à 12 étapes permettant l’identification d’agonistes puissants et présentant des propriétés pharmacocinétiques en accord avec notre stratégie de composés topiques intestinaux. Des études in vivo ont ensuite permis de valider l’effet GLP-1 sécrétagogue de tels composés. Enfin, l’évaluation d’un des meilleurs composés dans un modèle murin de diabète nous a permis de valider l’hypothèse qu’un agoniste topique intestinal de TGR5 peut avoir un effet bénéfique sur l’homéostasie énergétique et glucidique. / The membrane receptor TGR5 (Takeda G Protein-coupled Receptor 5) is an ubiquitous receptor sensitive to bile acids. It is expressed in many tissues and organs including the intestine (in enteroendocrine L cells), the gallbladder, smooth and skeletal muscles, brown adipose tissue and in some immune cells. In vitro and in vivo studies in animals have shown beneficial effects of TGR5 activation on energy and glucose homeostasis. It is now commonly accepted that the beneficial effects of TGR5 on glucose homeostasis are, at least in part, mediated by its ability to promote the secretion of the intestinal incretin glucagon-like peptide-1 (GLP-1) in enteroendocrine L cells.However, recent experiments have shown that the activation of TGR5 by systemic agonists in animal models can induce unwanted effects such as increased gallbladder volume, itching and cardiovascular issues. In order to avoid the undesired effects of systemic agonists of TGR5, the project focused on the development of TGR5 agonists with an intestine targeted distribution and a very low oral bioavailability. Then, we hypothesized that the activation of TGR5 limited to the intestinal epithelium without systemic exposure would promote the beneficial effects on glucose homeostasis via the GLP-1 secretagogue effect, while minimizing systemic effects on other tissues or organs expressing TGR5.On the basis of structure-activity relationships on a series of TGR5 agonists developed in the laboratory, we have designed chimeric compounds as follows: the pharmacophore responsible for activity on the TGR5 receptor is bound, via a linker, at structural elements called kinetophores that fine-tune the physicochemical and pharmacokinetic properties of our agonists to limit their intestinal absorption. Thus, the aim of this work was to obtain powerful and original non-systemic TGR5 agonists acting in the intestine to generate the in vivo proof of concept of the therapeutic potential of such agonists in the treatment of type 2 diabetes.A systematic study of the effect of various kinetophores was performed. About thirty compounds have been synthesized in 8 to 12 steps allowing the identification of powerful agonists with pharmacokinetic properties in accordance with our strategy of topical intestinal compounds. In vivo studies were then used to validate the GLP-1 secretagogue effect of such compounds. Finally, evaluation of one of the best compounds in a murine model of diabetes allowed us to validate the hypothesis that a topical intestinal agonist of TGR5 can have a beneficial effect on energy and glucose homeostasis.

No description available.

In response to ingestion of nutrients, enteroendocrine L cells secrete the incretin hormone, glucagon-like peptide-1 (GLP-1), to enhance glucose-dependent insulin release. Therapies related to GLP-1 are approved for type 2 diabetes. The GLP-1 receptor (GLP-1R) is expressed in cells of the gastrointestinal tract and elsewhere. In pancreatic beta cells, GLP-1R are coupled to the Gs/cAMP/PKA pathway. The expression and function of GLP-1R in gastrointestinal smooth muscle are not known. Aim. To test the hypothesis that GLP-1 regulates smooth muscle function by acting on GLP-1R expressed on smooth muscle. Methods. Smooth muscle cells (SMC) were isolated and cultured. Expression of GLP-1R mRNA was measured by RT-PCR. Expression of GLP-1R protein was measured by western blot. The effect of GLP-1 (7-36) amide on Gαs activation, cAMP formation, and PKA activity was examined in cultured SMC. The effect of GLP-1 on basal activity and on acetylcholine-induced contraction was measured in intact colon via organ bath. Results. Amplification of GLP-1R mRNA suggested expression of GLP-1R mRNA in mucosal and non-mucosal colon cells, which was confirmed in pure SMC cultures. Similar patterns of protein expression were obtained with western blot. Addition of GLP-1 caused relaxation of phasic activity and agonist-induced tonic contractions in intact colon, suggesting a role of smooth muscle Gs-coupled GLP-1R in mediating relaxation. In SMC, GLP-1 (7-36) amide activated Gas, increased cAMP levels, and stimulated PKA activity. Conclusion. Colonic SMC express GLP-1R, and GLP-1 inhibits both basal and acetylcholine-induced contraction. The GLP1-R is coupled to the heterotrimeric G protein, Gas.

Le TD2 est caractérisé par un état inflammatoire de bas grade qui compromet la sécrétion et l‘action de l‘insuline. L‘installation de cette inflammation semble être la conséquence de l‘intoxication aux polluants environnementaux tels que les POP (Polluants Organiques Persistants) et/ou le changement de la flore intestinale, induit par un régime riche en graisse (HFD). L‘intestin est l‘un des premiers tissus exposés aux bactéries pathogènes et à certains POP. Cet organe est aussi le premier impliqué dans la régulation de l‘homéostasie glucidique. Il est donc raisonnable de supposer qu‘une inflammation chronique de l‘intestin puisse avoir des conséquences sur le développement du TD2. Nos objectifs généraux étaient donc : d‘évaluer le rôle de l‘inflammation entérocytaire dans le développement du diabète TD2 et de clarifier l‘effet du Resvératrol (RSV) sur cette maladie. Nos résultats suggèrent que l'inflammation intestinale est impliquée dans l‘établissement d‘un TD2. Cette inflammation pourrait intervenir en libérant des cytokines inflammatoires, en diminuant le taux de GLP-1 et en favorisant le passage des facteurs diabétogènes, de l‘intestin vers les tissus cibles de l‘insuline. L‘induction ou la diminution de l‘inflammation intestinale par des facteurs inflammatogènes (BaP) ou anti-inflammatoires (RSV) sont respectivement associées à l‘aggravation ou à l‘amélioration de l‘état diabétique.Nous avons également montré que le RSV pourrait améliorer l‘état diabétique en normalisant la flore intestinale modifiée par un régime HFD et en augmentant la concentration de GLP-1.. De plus, une co-administration du RSV avec le sitagliptine, un inhibiteur de l‘enzyme DPP4, dégradant le GLP-1, montre une potentialisation de l‘effet du RSV par le sitagliptine: Ces résultats ouvrent la porte pour l‘utilisation de RSV dans la prévention et le traitement du TD2. / The TD2 is characterized by a low-grade inflammatory state that impairs the secretion and action of insulin. Environmental pollutants such as POP (Persistent Organic Pollutants) and the change in gut flora induced by a high fat diet (HFD), are suspected to play an important role in the installation of this inflammation.The intestine is one of the first tissues exposed to pathogenic bacteria and some POP. This organ is also the first take part in the regulation of glucose homeostasis. So, it is reasonable to assume that chronic inflammation of the bowel may affect the development of TD2. Our objectives were: to assess the role of inflammation in the enterocyte development of diabetes TD2 and clarify the effect of Resveratrol (RSV) on the disease.Our results suggest that intestinal inflammation is involved in the establishment of a TD2. This inflammation could affect TD2 through releasing inflammatory cytokines, reducing the concentration of GLP-1 and promoting the passage of diabetogenic factors from the intestine to target tissues of insulin. The induction or reduction of intestinal inflammation by factor inflammatory (BaP) or anti-inflammatory (RSV) are respectively associated with worsening or improvement of the diabetic state.We also showed that the RSV could improve the diabetic state by normalizing the intestinal flora modified by diet and HFD, by increasing the concentration of GLP-1. In addition, co-administration of sitagliptin with RSV, an inhibitor of the enzyme DPP4,which degrade GLP-1, shows a potentiation of the effect of RSV in the sitagliptin: These results open the door for the use of RSV in the prevention and treatment of TD2.Keywords: Resveratrol, type 2 diabetes