1
|
El K, Gray SM, Capozzi ME, Knuth ER, Jin E, Svendsen B, Clifford A, Brown JL, Encisco SE, Chazotte BM, Sloop KW, Nunez DJ, Merrins MJ, D'Alessio DA, Campbell JE. GIP mediates the incretin effect and glucose tolerance by dual actions on α cells and β cells. Sci Adv 2021; 7:7/11/eabf1948. [PMID: 33712466 PMCID: PMC7954443 DOI: 10.1126/sciadv.abf1948] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 01/26/2021] [Indexed: 05/23/2023]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) communicates nutrient intake from the gut to islets, enabling optimal levels of insulin secretion via the GIP receptor (GIPR) on β cells. The GIPR is also expressed in α cells, and GIP stimulates glucagon secretion; however, the role of this action in the postprandial state is unknown. Here, we demonstrate that GIP potentiates amino acid-stimulated glucagon secretion, documenting a similar nutrient-dependent action to that described in β cells. Moreover, we demonstrate that GIP activity in α cells contributes to insulin secretion by invoking paracrine α to β cell communication. Last, specific loss of GIPR activity in α cells prevents glucagon secretion in response to a meal stimulus, limiting insulin secretion and driving glucose intolerance. Together, these data uncover an important axis by which GIPR activity in α cells is necessary to coordinate the optimal level of both glucagon and insulin secretion to maintain postprandial homeostasis.
Collapse
Affiliation(s)
- K El
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
| | - S M Gray
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
| | - M E Capozzi
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
| | - E R Knuth
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - E Jin
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - B Svendsen
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
| | - A Clifford
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
| | - J L Brown
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
| | - S E Encisco
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
| | - B M Chazotte
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
| | - K W Sloop
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN, USA
| | - D J Nunez
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
| | - M J Merrins
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - D A D'Alessio
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
- Division of Endocrinology, Department of Medicine, Duke University, Durham, NC, USA
| | - J E Campbell
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA.
- Division of Endocrinology, Department of Medicine, Duke University, Durham, NC, USA
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, USA
| |
Collapse
|