1. Physiological and Pharmacological Mechanisms through which the DPP-4 Inhibitor Sitagliptin Regulates Glycemia in Mice
- Author
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Pierre Cattan, Julien Castel, Rémy Burcelin, Aurélie Waget, Daniel J. Drucker, Mattieu Armanet, Melis Karaca, Christophe Magnan, Jens J. Holst, Céline Garret, Thierry Sulpice, Gaëlle Payros, Myriam Masseboeuf, Adriano Maida, Cendrine Cabou, Institut des Maladies Métaboliques et Cardiovasculaires ( I2MC ), Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Hôpital de Rangueil, CHU Toulouse [Toulouse]-CHU Toulouse [Toulouse]-Université Toulouse III - Paul Sabatier ( UPS ), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Cell Therapy Unit, Assistance publique - Hôpitaux de Paris (AP-HP)-Université Paris Diderot - Paris 7 ( UPD7 ) -Groupe Hospitalier Saint Louis - Lariboisière - Fernand Widal [Paris], Centre de Recherche des Cordeliers ( CRC (UMR_S 872) ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Université Paris Descartes - Paris 5 ( UPD5 ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Biologie Fonctionnelle et Adaptative ( BFA ), Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ), Department of Medicine, University of Toronto-Samuel Lunenfeld Research Institute-Mount Sinai Hospital ( MSH ), Physiogenex SAS, Prologue Biotech, PHYSIOGENEX S.A.S, Department of Biomedical Sciences, The panum Institute-University of Copenhagen ( KU ), Institut des Maladies Métaboliques et Cardiovasculaires (I2MC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Université Paris Diderot - Paris 7 (UPD7)-Groupe Hospitalier Saint Louis - Lariboisière - Fernand Widal [Paris], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Centre de Recherche des Cordeliers (CRC (UMR_S 872)), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Unité de Biologie Fonctionnelle et Adaptative (BFA (UMR_8251 / U1133)), Université Paris Diderot - Paris 7 (UPD7)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), University of Toronto-Samuel Lunenfeld Research Institute-Mount Sinai Hospital [Toronto, Canada] (MSH), Physiogenex, Department of Biomedical Sciences [Copenhagen], Faculty of Health and Medical Sciences, University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), Simon, Marie Francoise, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Santé et de la Recherche Médicale (INSERM), Université Paris Descartes - Paris 5 (UPD5)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), University of Toronto-Mount Sinai Hospital [Toronto, Canada] (MSH)-Samuel Lunenfeld Research Institute, and University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU)
- Subjects
MESH : Insulin ,medicine.medical_treatment ,MESH : Vagus Nerve ,MESH : Receptors, Glucagon ,0302 clinical medicine ,Endocrinology ,MESH: Dipeptides ,MESH: Vagus Nerve ,Glucose homeostasis ,MESH: Animals ,[SDV.MHEP.EM] Life Sciences [q-bio]/Human health and pathology/Endocrinology and metabolism ,MESH : Dipeptidyl-Peptidase IV Inhibitors ,0303 health sciences ,Glucose tolerance test ,MESH: Middle Aged ,MESH: Dipeptidyl-Peptidase IV Inhibitors ,medicine.diagnostic_test ,MESH : Glucagon ,MESH: Glucagon ,digestive, oral, and skin physiology ,[SDV.MHEP.EM]Life Sciences [q-bio]/Human health and pathology/Endocrinology and metabolism ,MESH : Adult ,[ SDV.MHEP.EM ] Life Sciences [q-bio]/Human health and pathology/Endocrinology and metabolism ,Glucagon-like peptide-1 ,3. Good health ,MESH : Pyrazines ,MESH: Pyrazines ,Sitagliptin ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug ,endocrine system ,medicine.medical_specialty ,MESH: Glucose Tolerance Test ,MESH : Male ,MESH : Dipeptides ,MESH : Receptors, Gastrointestinal Hormone ,Incretin ,030209 endocrinology & metabolism ,MESH: Insulin ,MESH : Mice, Inbred C57BL ,Biology ,Sitagliptin Phosphate ,MESH : Glucose Tolerance Test ,MESH: Receptors, Glucagon ,03 medical and health sciences ,MESH: Mice, Inbred C57BL ,Internal medicine ,MESH : Mice ,MESH : Triazoles ,medicine ,MESH : Middle Aged ,MESH: Mice ,Dipeptidyl peptidase-4 ,030304 developmental biology ,MESH: Humans ,MESH: Receptors, Gastrointestinal Hormone ,Insulin ,MESH : Humans ,MESH: Adult ,MESH: Dipeptidyl Peptidase 4 ,MESH : Blood Glucose ,MESH: Male ,MESH: Triazoles ,MESH : Dipeptidyl Peptidase 4 ,MESH: Blood Glucose ,MESH : Animals - Abstract
International audience; Inhibition of dipeptidyl peptidase-4 (DPP-4) activity improves glucose homeostasis through a mode of action related to the stabilization of the active forms of DPP-4-sensitive hormones such as the incretins that enhance glucose-induced insulin secretion. However, the DPP-4 enzyme is highly expressed on the surface of intestinal epithelial cells; hence, the role of intestinal vs. systemic DPP-4 remains unclear. To analyze mechanisms through which the DPP-4 inhibitor sitagliptin regulates glycemia in mice, we administered low oral doses of the DPP-4 inhibitor sitagliptin that selectively reduced DPP-4 activity in the intestine. Glp1r(-/-) and Gipr(-/-) mice were studied and glucagon-like peptide (GLP)-1 receptor (GLP-1R) signaling was blocked by an i.v. infusion of the corresponding receptor antagonist exendin (9-39). The role of the dipeptides His-Ala and Tyr-Ala as DPP-4-generated GLP-1 and glucose-dependent insulinotropic peptide (GIP) degradation products was studied in vivo and in vitro on isolated islets. We demonstrate that very low doses of oral sitagliptin improve glucose tolerance and plasma insulin levels with selective reduction of intestinal but not systemic DPP-4 activity. The glucoregulatory action of sitagliptin was associated with increased vagus nerve activity and was diminished in wild-type mice treated with the GLP-1R antagonist exendin (9-39) and in Glp1r(-/-) and Gipr(-/-) mice. Furthermore, the dipeptides liberated from GLP-1 (His-Ala) and GIP (Tyr-Ala) deteriorated glucose tolerance, reduced insulin, and increased portal glucagon levels. The predominant mechanism through which DPP-4 inhibitors regulate glycemia involves local inhibition of intestinal DPP-4 activity, activation of incretin receptors, reduced liberation of bioactive dipeptides, and activation of the gut-to-pancreas neural axis.
- Published
- 2011