1
|
Kim T, Holleman CL, Nason S, Arble DM, Ottaway N, Chabenne J, Loyd C, Kim JA, Sandoval D, Drucker DJ, DiMarchi R, Perez-Tilve D, Habegger KM. Hepatic Glucagon Receptor Signaling Enhances Insulin-Stimulated Glucose Disposal in Rodents. Diabetes 2018; 67:2157-2166. [PMID: 30150304 PMCID: PMC6198333 DOI: 10.2337/db18-0068] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 08/10/2018] [Indexed: 12/12/2022]
Abstract
Glucagon receptor (GCGR) agonists cause hyperglycemia but also weight loss. However, GCG-like peptide 1 receptor (GLP1R)/GCGR mixed agonists do not exhibit the diabetogenic effects often attributed to GCGR activity. Thus, we sought to investigate the effect of glucagon agonism on insulin action and glucose homeostasis. Acute GCGR agonism induced immediate hyperglycemia, followed by improved glucose tolerance and enhanced glucose-stimulated insulin secretion. Moreover, acute GCGR agonism improved insulin tolerance in a dose-dependent manner in both lean and obese mice. Improved insulin tolerance was independent of GLP1R, FGF21, and hepatic glycogenolysis. Moreover, we observed increased glucose infusion rate, disposal, uptake, and suppressed endogenous glucose production during euglycemic clamps. Mice treated with insulin and GCGR agonist had enhanced phosphorylation of hepatic AKT at Ser473; this effect was reproduced in isolated mouse primary hepatocytes and resulted in increased AKT kinase activity. These data reveal that GCGR agonism enhances glucose tolerance, in part, by augmenting insulin action, with implications for the use of GCGR agonism in therapeutic strategies for diabetes.
Collapse
Affiliation(s)
- Teayoun Kim
- Comprehensive Diabetes Center and Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | - Cassie L Holleman
- Comprehensive Diabetes Center and Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | - Shelly Nason
- Comprehensive Diabetes Center and Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | - Deanna M Arble
- Department of Biological Sciences, Marquette University, Milwaukee, WI
| | - Nickki Ottaway
- Metabolic Diseases Institute and Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Cincinnati, Cincinnati, OH
| | | | - Christine Loyd
- Comprehensive Diabetes Center and Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | - Jeong-A Kim
- Comprehensive Diabetes Center and Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | | | - Daniel J Drucker
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Richard DiMarchi
- Novo Nordisk Research Center, Indianapolis, IN
- Department of Chemistry, Indiana University, Bloomington, IN
| | - Diego Perez-Tilve
- Metabolic Diseases Institute and Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Cincinnati, Cincinnati, OH
| | - Kirk M Habegger
- Comprehensive Diabetes Center and Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| |
Collapse
|
2
|
Kim T, Holleman CL, Ptacek T, Morrow CD, Habegger KM. Duodenal endoluminal barrier sleeve alters gut microbiota of ZDF rats. Parasite Immunol 2016; 39. [PMID: 27924082 DOI: 10.1111/pim.12404] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 11/24/2016] [Indexed: 12/31/2022]
Abstract
BACKGROUND/OBJECTIVES The combination of energy dense diets and reduced energy expenditure in modern society has escalated the prevalence of obesity and obesity-related comorbidities. Among these disease states, type-2 diabetics (T2D) are disproportionately associated with obesity, suggesting a shared etiology. In conjunction with defects in hormonal and inflammatory states, obesity and T2D are also characterized by dysbiosis. METHODS We have recently described the beneficial effects of duodenal nutrient exclusion, as induced by the duodenal endoluminal sleeve (DES); including body weight loss, prevented fat mass accumulation, and improved glucose tolerance in the ZDF rat, a rodent model of obesity and type-2 diabetes (T2D). To assess the relative role of DES on hindgut microbiota in the context of these metabolic changes, we analyzed cecal samples from rats implanted with a duodenal endoluminal sleeve (DES), or a sham control of this procedure. A group of pair-fed (pf) sham controls was also included to account for changes induced by reduced body weight and food intake. RESULTS Analysis of hindgut microbiota following DES in the ZDF rat elucidated discrete changes in several microbial populations including a reduction in Paraprevotella family members of the Clostridiales order along with an increase in Akkermansia muciniphila and species of the Allobaculum and Bifidobacterium genera. CONCLUSIONS Altogether, these observations suggest that like Roux-en Y gastric bypass (RYGB) and Metformin, regulation of gut microbiota may be a contributing factor to the therapeutic effects of DES.
Collapse
Affiliation(s)
- T Kim
- Comprehensive Diabetes Center and Department of Medicine-Endocrinology, Diabetes and Metabolism, University of Alabama at Birmingham, Birmingham, AL, USA
| | - C L Holleman
- Comprehensive Diabetes Center and Department of Medicine-Endocrinology, Diabetes and Metabolism, University of Alabama at Birmingham, Birmingham, AL, USA
| | - T Ptacek
- Center for Clinical and Translational Sciences, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - C D Morrow
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Cell Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - K M Habegger
- Comprehensive Diabetes Center and Department of Medicine-Endocrinology, Diabetes and Metabolism, University of Alabama at Birmingham, Birmingham, AL, USA
| |
Collapse
|
3
|
Warr GA, Martin RR, Holleman CL, Criswell BS. Classification of bronchial lymphocytes from nonsmokers and smokers. Am Rev Respir Dis 1976; 113:96-100. [PMID: 1082283 DOI: 10.1164/arrd.1976.113.1.96] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The population of lymphocytes obtained by endobronchial lavage is significantly different from the distribution of lymphocytes in the peripheral blood. Both B and T lymphocytes are found in fluids lavaged from the normal human lung. Of the lymphocytes that can be classified, the T cell population is larger than the B cell population in both nonsmokers and cigarette smokers, whereas a further increment in T cells is noted in smokers. A third population of unclassified lymphocytes, the "null" cells, also comprise a large portion of the lymphocyte population in both smokers and nonsmokers. Their significance has yet to be determined.
Collapse
|