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Gerstenberg MK, Andersen DB, Torz L, Castorena CM, Bookout AL, Hartmann B, Rehfeld JF, Petersen N, Holst JJ, Kuhre RE. Weight loss by calorie restriction does not alter appetite-regulating gut hormone responses from perfused rat small intestine. Acta Physiol (Oxf) 2023; 238:e13947. [PMID: 36755506 DOI: 10.1111/apha.13947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 01/27/2023] [Accepted: 02/06/2023] [Indexed: 02/10/2023]
Abstract
AIM Postprandial secretion of the appetite-inhibiting hormones, glucagon-like peptide-1 (GLP-1), and peptide YY are reduced with obesity. It is unclear if the reduced secretion persists following weight loss (WL), if other appetite-inhibiting hormones are also reduced, and if so whether reduced secretion results from intrinsic changes in the gut. METHODS To address whether WL may restore secretion of GLP-1 and other appetite-inhibiting hormones, we performed a gut perfusion study of the small intestine in diet-induced obese (DIO) rats after WL. A 20% weight loss (means ± SEM (g): 916 ± 53 vs. 703 ± 35, p < 0.01, n = 7) was induced by calorie restriction, and maintained stable for ≥7 days prior to gut perfusion to allow for complete renewal of enteroendocrine cells. Age-matched DIO rats were used as comparator. Several gut hormones were analyzed from the venous effluent, and gene expression was performed on gut tissue along the entire length of the intestine. RESULTS Secretion of cholecystokinin, gastrin, glucose-dependent insulinotropic peptide, GLP-1, neurotensin, and somatostatin was not affected by WL during basal conditions (p ≥ 0.25) or in response to macronutrients and bile acids (p ≥ 0.14). Glucose absorption was indistinguishable following WL. The expression of genes encoding the studied peptides, macronutrient transporters (glucose, fructose, and di-/tripeptides) and bile acid receptors did also not differ between DIO and WL groups. CONCLUSIONS These data suggest that the attenuated postprandial responses of GLP-1, as well as reduced responses of other appetite-inhibiting gut hormones, in people living with obesity may persist after weight loss and may contribute to their susceptibility for weight regain.
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Affiliation(s)
| | - Daniel B Andersen
- Department of Biomedical Sciences, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Center for Basic Metabolic Research, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark
| | - Lola Torz
- Global Drug Discovery, Novo Nordisk A/S, Måløv, Denmark
| | | | - Angie L Bookout
- Global Drug Discovery, Novo Nordisk A/S, Seattle, Washington, USA
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Center for Basic Metabolic Research, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark
| | - Jens F Rehfeld
- Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | | | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Center for Basic Metabolic Research, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark.,Global Drug Discovery, Novo Nordisk A/S, Måløv, Denmark
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2
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Grunddal KV, Trammell SAJ, Bæch-Laursen C, Andersen DB, Xu SFS, Andersen H, Gillum MP, Ghiasi SM, Novak I, Tyrberg B, Li C, Rosenkilde MM, Hartmann B, Holst JJ, Kuhre RE. Opposing roles of the entero-pancreatic hormone urocortin-3 in glucose metabolism in rats. Diabetologia 2022; 65:1018-1031. [PMID: 35325259 PMCID: PMC9076751 DOI: 10.1007/s00125-022-05675-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 12/20/2021] [Indexed: 11/03/2022]
Abstract
AIM/HYPOTHESIS Urocortin-3 (UCN3) is a glucoregulatory peptide produced in the gut and pancreatic islets. The aim of this study was to clarify the acute effects of UCN3 on glucose regulation following an oral glucose challenge and to investigate the mechanisms involved. METHODS We studied the effect of UCN3 on blood glucose, gastric emptying, glucose absorption and secretion of gut and pancreatic hormones in male rats. To supplement these physiological studies, we mapped the expression of UCN3 and the UCN3-sensitive receptor, type 2 corticotropin-releasing factor receptor (CRHR2), by means of fluorescence in situ hybridisation and by gene expression analysis. RESULTS In rats, s.c. administration of UCN3 strongly inhibited gastric emptying and glucose absorption after oral administration of glucose. Direct inhibition of gastrointestinal motility may be responsible because UCN3's cognate receptor, CRHR2, was detected in gastric submucosal plexus and in interstitial cells of Cajal. Despite inhibited glucose absorption, post-challenge blood glucose levels matched those of rats given vehicle in the low-dose UCN3 group, because UCN3 concomitantly inhibited insulin secretion. Higher UCN3 doses did not further inhibit gastric emptying, but the insulin inhibition progressed resulting in elevated post-challenge glucose and lipolysis. Incretin hormones and somatostatin (SST) secretion from isolated perfused rat small intestine was unaffected by UCN3 infusion; however, UCN3 infusion stimulated secretion of somatostatin from delta cells in the isolated perfused rat pancreas which, unlike alpha cells and beta cells, expressed Crhr2. Conversely, acute antagonism of CRHR2 signalling increased insulin secretion by reducing SST signalling. Consistent with these observations, acute drug-induced inhibition of CRHR2 signalling improved glucose tolerance in rats to a similar degree as administration of glucagon-like peptide-1. UCN3 also powerfully inhibited glucagon secretion from isolated perfused rat pancreas (perfused with 3.5 mmol/l glucose) in a SST-dependent manner, suggesting that UCN3 may be involved in glucose-induced inhibition of glucagon secretion. CONCLUSIONS/INTERPRETATION Our combined data indicate that UCN3 is an important glucoregulatory hormone that acts through regulation of gastrointestinal and pancreatic functions.
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Affiliation(s)
- Kaare V Grunddal
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Samuel A J Trammell
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Cecilie Bæch-Laursen
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Daniel B Andersen
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Stella F S Xu
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Helle Andersen
- Global Obesity and Liver Disease Research, Novo Nordisk, Måløv, Denmark
| | - Matthew P Gillum
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Seyed M Ghiasi
- Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College, London, UK
| | - Ivana Novak
- Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Björn Tyrberg
- Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Chien Li
- Global Obesity and Liver Disease Research, Novo Nordisk, Seattle, WA, USA
| | - Mette M Rosenkilde
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark.
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark.
- Global Obesity and Liver Disease Research, Novo Nordisk, Måløv, Denmark.
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3
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Kuhre RE, Deacon CF, Wewer Albrechtsen NJ, Holst JJ. Do sodium-glucose co-transporter-2 inhibitors increase plasma glucagon by direct actions on the alpha cell? And does the increase matter for the associated increase in endogenous glucose production? Diabetes Obes Metab 2021; 23:2009-2019. [PMID: 33961344 DOI: 10.1111/dom.14422] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/21/2021] [Accepted: 05/04/2021] [Indexed: 12/12/2022]
Abstract
Sodium-glucose co-transporter-2 inhibitors (SGLT2is) lower blood glucose and are used for treatment of type 2 diabetes. However, SGLT2is have been associated with increases in endogenous glucose production (EGP) by mechanisms that have been proposed to result from SGLT2i-mediated increases in circulating glucagon concentrations, but the relative importance of this effect is debated, and mechanisms possibly coupling SGLT2is to increased plasma glucagon are unclear. A direct effect on alpha-cell activity has been proposed, but data on alpha-cell SGLT2 expression are inconsistent, and studies investigating the direct effects of SGLT2 inhibition on glucagon secretion are conflicting. By contrast, alpha-cell sodium-glucose co-transporter-1 (SGLT1) expression has been found more consistently and appears to be more prominent, pointing to an underappreciated role for this transporter. Nevertheless, the selectivity of most SGLT2is does not support interference with SGLT1 during therapy. Paracrine effects mediated by secretion of glucagonotropic/static molecules from beta and/or delta cells have also been suggested to be involved in SGLT2i-induced increase in plasma glucagon, but studies are few and arrive at different conclusions. It is also possible that the effect on glucagon is secondary to drug-induced increases in urinary glucose excretion and lowering of blood glucose, as shown in experiments with glucose clamping where SGLT2i-associated increases in plasma glucagon are prevented. However, regardless of the mechanisms involved, the current balance of evidence does not support that SGLT2 plays a crucial role for alpha-cell physiology or that SGLT2i-induced glucagon secretion is important for the associated increased EGP, particularly because the increase in EGP occurs before any rise in plasma glucagon.
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Affiliation(s)
- Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Obesity Pharmacology, Novo Nordisk, Måløv, Denmark
| | - Carolyn F Deacon
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- School of Biomedical Sciences, Ulster University, Coleraine, UK
| | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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4
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Andersen DB, Grunddal KV, Pedersen J, Kuhre RE, Lund ML, Holst JJ, Ørskov C. Using a Reporter Mouse to Map Known and Novel Sites of GLP-1 Receptor Expression in Peripheral Tissues of Male Mice. Endocrinology 2021; 162:6122689. [PMID: 33508122 DOI: 10.1210/endocr/bqaa246] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Indexed: 02/07/2023]
Abstract
Glucagon-like peptide-1 receptor (GLP-1R) activation is used in the treatment of diabetes and obesity; however, GLP-1 induces many other physiological effects with unclear mechanisms of action. To identify the cellular targets of GLP-1 and GLP-1 analogues, we generated a Glp1r.tdTomato reporter mouse expressing the reporter protein, tdTomato, in Glp1r-expressing cells. The reporter signal is expressed in all cells where GLP-1R promoter was ever active. To complement this, we histologically mapped tdTomato-fluorescence, and performed Glp-1r mRNA in situ hybridization and GLP-1R immunohistochemistry on the same tissues. In male mice, we found tdTomato signal in mucus neck, chief, and parietal cells of the stomach; Brunner's glands; small intestinal enteroendocrine cells and intraepithelial lymphocytes; and myenteric plexus nerve fibers throughout the gastrointestinal tract. Pancreatic acinar-, β-, and δ cells, but rarely α cells, were tdTomato-positive, as were renal arteriolar smooth muscle cells; endothelial cells of the liver, portal vein, and endocardium; aortal tunica media; and lung type 1 and type 2 pneumocytes. Some thyroid follicular and parafollicular cells displayed tdTomato expression, as did tracheal cartilage chondrocytes, skin fibroblasts, and sublingual gland mucus cells. In conclusion, our reporter mouse is a powerful tool for mapping known and novel sites of GLP-1R expression in the mouse, thus enhancing our understanding of the many target cells and effects of GLP-1 and GLP-1R agonists.
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Affiliation(s)
- Daniel B Andersen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kaare V Grunddal
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Copenhagen, Denmark
| | - Jens Pedersen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Copenhagen, Denmark
- Department of Endocrinology and Nephrology, Nordsjællands Hospital Hillerød, University of Copenhagen, Hillerød, Denmark
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mari L Lund
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Cathrine Ørskov
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Copenhagen, Denmark
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5
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Kuhre RE, Deacon CF, Holst JJ, Petersen N. What Is an L-Cell and How Do We Study the Secretory Mechanisms of the L-Cell? Front Endocrinol (Lausanne) 2021; 12:694284. [PMID: 34168620 PMCID: PMC8218725 DOI: 10.3389/fendo.2021.694284] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 05/11/2021] [Indexed: 12/14/2022] Open
Abstract
Synthetic glucagon-like peptide-1 (GLP-1) analogues are effective anti-obesity and anti-diabetes drugs. The beneficial actions of GLP-1 go far beyond insulin secretion and appetite, and include cardiovascular benefits and possibly also beneficial effects in neurodegenerative diseases. Considerable reserves of GLP-1 are stored in intestinal endocrine cells that potentially might be mobilized by pharmacological means to improve the body's metabolic state. In recognition of this, the interest in understanding basic L-cell physiology and the mechanisms controlling GLP-1 secretion, has increased considerably. With a view to home in on what an L-cell is, we here present an overview of available data on L-cell development, L-cell peptide expression profiles, peptide production and secretory patterns of L-cells from different parts of the gut. We conclude that L-cells differ markedly depending on their anatomical location, and that the traditional definition of L-cells as a homogeneous population of cells that only produce GLP-1, GLP-2, glicentin and oxyntomodulin is no longer tenable. We suggest to sub-classify L-cells based on their differential peptide contents as well as their differential expression of nutrient sensors, which ultimately determine the secretory responses to different stimuli. A second purpose of this review is to describe and discuss the most frequently used experimental models for functional L-cell studies, highlighting their benefits and limitations. We conclude that no experimental model is perfect and that a comprehensive understanding must be built on results from a combination of models.
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Affiliation(s)
- Rune E. Kuhre
- Department of Obesity Pharmacology, Novo Nordisk, Måløv, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- *Correspondence: Rune E. Kuhre, ;
| | - Carolyn F. Deacon
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
- School of Biomedical Sciences, Ulster University, Coleraine, United Kingdom
| | - Jens J. Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
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6
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Jonsson I, Bojsen-Møller KN, Kristiansen VB, Veedfald S, Wewer Albrechtsen NJ, Clausen TR, Kuhre RE, Rehfeld JF, Holst JJ, Madsbad S, Svane MS. Effects of Manipulating Circulating Bile Acid Concentrations on Postprandial GLP-1 Secretion and Glucose Metabolism After Roux-en-Y Gastric Bypass. Front Endocrinol (Lausanne) 2021; 12:681116. [PMID: 34084153 PMCID: PMC8166580 DOI: 10.3389/fendo.2021.681116] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 04/16/2021] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Altered bile acid (BA) turnover has been suggested to be involved in the improved glucose regulation after Roux-en-Y gastric bypass (RYGB), possibly via stimulation of GLP-1 secretion. We investigated the role of exogenous as well as endogenous BAs for GLP-1 secretion after RYGB by administering chenodeoxycholic acid (CDCA) and the BA sequestrant colesevelam (COL) both in the presence and the absence of a meal stimulus. METHODS Two single-blinded randomized cross-over studies were performed. In study 1, eight RYGB operated participants ingested 200 ml water with 1) CDCA 1.25 g or 2) CDCA 1.25 g + colesevelam 3.75 g on separate days. In study 2, twelve RYGB participants ingested on separate days a mixed meal with addition of 1) CDCA 1.25 g, 2) COL 3.75 g or 3) COL 3.75 g × 2, or 4) no additions. RESULTS In study 1, oral intake of CDCA increased circulating BAs, GLP-1, C-peptide, glucagon, and neurotensin. Addition of colesevelam reduced all responses. In study 2, addition of CDCA enhanced meal-induced increases in plasma GLP-1, glucagon and FGF-19 and lowered plasma glucose and C-peptide concentrations, while adding colesevelam lowered circulating BAs but did not affect meal-induced changes in plasma glucose or measured gastrointestinal hormones. CONCLUSION In RYGB-operated persons, exogenous CDCA enhanced meal-stimulated GLP-1 and glucagon secretion but not insulin secretion, while the BA sequestrant colesevelam decreased CDCA-stimulated GLP-1 secretion but did not affect meal-stimulated GLP-1, C-peptide or glucagon secretion, or glucose tolerance. These findings suggest a limited role for endogenous bile acids in the acute regulation of postprandial gut hormone secretion or glucose metabolism after RYGB.
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Affiliation(s)
- Isabella Jonsson
- Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark
| | - Kirstine N. Bojsen-Møller
- Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Simon Veedfald
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nicolai J. Wewer Albrechtsen
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Biochemistry Rigshospitalet, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
| | | | - Rune E. Kuhre
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Research and Development, Novo Nordisk A/S, Måløv, Denmark
| | - Jens F. Rehfeld
- Department of Clinical Biochemistry Rigshospitalet, Copenhagen, Denmark
| | - Jens J. Holst
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sten Madsbad
- Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- *Correspondence: Sten Madsbad, ; Maria S. Svane,
| | - Maria S. Svane
- Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Surgical Gastroenterology, Hvidovre Hospital, Hvidovre, Denmark
- *Correspondence: Sten Madsbad, ; Maria S. Svane,
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7
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Kuhre RE, Modvig IM, Jepsen SL, Kizilkaya HS, Bæch-Laursen C, Smith CA, Reimann F, Gribble FM, Rosenkilde MM, Holst JJ. L-Cell Expression of Melanocortin-4-Receptor Is Marginal in Most of the Small Intestine in Mice and Humans and Direct Stimulation of Small Intestinal Melanocortin-4-Receptors in Mice and Rats Does Not Affect GLP-1 Secretion. Front Endocrinol (Lausanne) 2021; 12:690387. [PMID: 34421821 PMCID: PMC8375664 DOI: 10.3389/fendo.2021.690387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/18/2021] [Indexed: 11/17/2022] Open
Abstract
The molecular sensors underlying nutrient-stimulated GLP-1 secretion are currently being investigated. Peripheral administration of melanocortin-4 receptor (MC4R) agonists have been reported to increase GLP-1 plasma concentrations in mice and humans but it is unknown whether this effect results from a direct effect on the GLP-1 secreting L-cells in the intestine, from other effects in the intestine or from extra-intestinal effects. We investigated L-cell expression of MC4R in mouse and human L-cells by reanalyzing publicly available RNA sequencing databases (mouse and human) and by RT-qPCR (mouse), and assessed whether administration of MC4R agonists to a physiologically relevant gut model, isolated perfused mouse and rat small intestine, would stimulate GLP-1 secretion or potentiate glucose-stimulated secretion. L-cell MC4R expression was low in mouse duodenum and hardly detectable in the ileum and MC4R expression was hardly detectable in human L-cells. In isolated perfused mouse and rat intestine, neither intra-luminal nor intra-arterial administration of NDP-alpha-MSH, a potent MC4R agonist, had any effect on GLP-1 secretion (P ≥0.98, n = 5-6) from the upper or lower-half of the small intestine in mice or in the lower half in rats. Furthermore, HS014-an often used MC4R antagonist, which we found to be a partial agonist-did not affect the glucose-induced GLP-1 response in the rat, P = 0.62, n = 6). Studies on transfected COS7-cells confirmed bioactivity of the used compounds and that concentrations employed were well within in the effective range. Our combined data therefore suggest that MC4R-activated GLP-1 secretion in rodents either exclusively occurs in the colon or involves extra-intestinal signaling.
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Affiliation(s)
- Rune E. Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Obesity Pharmacology, Novo Nordisk, Måløv, Denmark
- *Correspondence: Rune E. Kuhre, ; Jens J. Holst,
| | - Ida M. Modvig
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sara L. Jepsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hüsün S. Kizilkaya
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Cecilie Bæch-Laursen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Christopher A. Smith
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Addenbrooke’s Hospital, University of Cambridge, Cambridge, United Kingdom
| | - Frank Reimann
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Addenbrooke’s Hospital, University of Cambridge, Cambridge, United Kingdom
| | - Fiona M. Gribble
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Addenbrooke’s Hospital, University of Cambridge, Cambridge, United Kingdom
| | - Mette M. Rosenkilde
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens J. Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- *Correspondence: Rune E. Kuhre, ; Jens J. Holst,
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8
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Winther-Sørensen M, Galsgaard KD, Santos A, Trammell SAJ, Sulek K, Kuhre RE, Pedersen J, Andersen DB, Hassing AS, Dall M, Treebak JT, Gillum MP, Torekov SS, Windeløv JA, Hunt JE, Kjeldsen SAS, Jepsen SL, Vasilopoulou CG, Knop FK, Ørskov C, Werge MP, Bisgaard HC, Eriksen PL, Vilstrup H, Gluud LL, Holst JJ, Wewer Albrechtsen NJ. Glucagon acutely regulates hepatic amino acid catabolism and the effect may be disturbed by steatosis. Mol Metab 2020; 42:101080. [PMID: 32937194 PMCID: PMC7560169 DOI: 10.1016/j.molmet.2020.101080] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 08/28/2020] [Accepted: 09/09/2020] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVE Glucagon is well known to regulate blood glucose but may be equally important for amino acid metabolism. Plasma levels of amino acids are regulated by glucagon-dependent mechanism(s), while amino acids stimulate glucagon secretion from alpha cells, completing the recently described liver-alpha cell axis. The mechanisms underlying the cycle and the possible impact of hepatic steatosis are unclear. METHODS We assessed amino acid clearance in vivo in mice treated with a glucagon receptor antagonist (GRA), transgenic mice with 95% reduction in alpha cells, and mice with hepatic steatosis. In addition, we evaluated urea formation in primary hepatocytes from ob/ob mice and humans, and we studied acute metabolic effects of glucagon in perfused rat livers. We also performed RNA sequencing on livers from glucagon receptor knock-out mice and mice with hepatic steatosis. Finally, we measured individual plasma amino acids and glucagon in healthy controls and in two independent cohorts of patients with biopsy-verified non-alcoholic fatty liver disease (NAFLD). RESULTS Amino acid clearance was reduced in mice treated with GRA and mice lacking endogenous glucagon (loss of alpha cells) concomitantly with reduced production of urea. Glucagon administration markedly changed the secretion of rat liver metabolites and within minutes increased urea formation in mice, in perfused rat liver, and in primary human hepatocytes. Transcriptomic analyses revealed that three genes responsible for amino acid catabolism (Cps1, Slc7a2, and Slc38a2) were downregulated both in mice with hepatic steatosis and in mice with deletion of the glucagon receptor. Cultured ob/ob hepatocytes produced less urea upon stimulation with mixed amino acids, and amino acid clearance was lower in mice with hepatic steatosis. Glucagon-induced ureagenesis was impaired in perfused rat livers with hepatic steatosis. Patients with NAFLD had hyperglucagonemia and increased levels of glucagonotropic amino acids, including alanine in particular. Both glucagon and alanine levels were reduced after diet-induced reduction in Homeostatic Model Assessment for Insulin Resistance (HOMA-IR, a marker of hepatic steatosis). CONCLUSIONS Glucagon regulates amino acid metabolism both non-transcriptionally and transcriptionally. Hepatic steatosis may impair glucagon-dependent enhancement of amino acid catabolism.
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Affiliation(s)
- Marie Winther-Sørensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Katrine D Galsgaard
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Alberto Santos
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Samuel A J Trammell
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Karolina Sulek
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens Pedersen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Daniel B Andersen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anna S Hassing
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Morten Dall
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jonas T Treebak
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Matthew P Gillum
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Signe S Torekov
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Johanne A Windeløv
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jenna E Hunt
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sasha A S Kjeldsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sara L Jepsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Catherine G Vasilopoulou
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Munich, Germany
| | - Filip K Knop
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Steno Diabetes Center Copenhagen, Gentofte, Denmark
| | - Cathrine Ørskov
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mikkel P Werge
- Gastrounit, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark
| | - Hanne Cathrine Bisgaard
- Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Peter Lykke Eriksen
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark
| | - Hendrik Vilstrup
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark
| | - Lise Lotte Gluud
- Gastrounit, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Department for Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
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9
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Madsen TD, Hansen LH, Hintze J, Ye Z, Jebari S, Andersen DB, Joshi HJ, Ju T, Goetze JP, Martin C, Rosenkilde MM, Holst JJ, Kuhre RE, Goth CK, Vakhrushev SY, Schjoldager KT. An atlas of O-linked glycosylation on peptide hormones reveals diverse biological roles. Nat Commun 2020; 11:4033. [PMID: 32820167 PMCID: PMC7441158 DOI: 10.1038/s41467-020-17473-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 07/02/2020] [Indexed: 12/17/2022] Open
Abstract
Peptide hormones and neuropeptides encompass a large class of bioactive peptides that regulate physiological processes like anxiety, blood glucose, appetite, inflammation and blood pressure. Here, we execute a focused discovery strategy to provide an extensive map of O-glycans on peptide hormones. We find that almost one third of the 279 classified peptide hormones carry O-glycans. Many of the identified O-glycosites are conserved and are predicted to serve roles in proprotein processing, receptor interaction, biodistribution and biostability. We demonstrate that O-glycans positioned within the receptor binding motifs of members of the neuropeptide Y and glucagon families modulate receptor activation properties and substantially extend peptide half-lives. Our study highlights the importance of O-glycosylation in the biology of peptide hormones, and our map of O-glycosites in this large class of biomolecules serves as a discovery platform for an important class of molecules with potential opportunities for drug designs.
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Affiliation(s)
- Thomas D Madsen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark
| | - Lasse H Hansen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark.,Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, DK-2100, Copenhagen O, Denmark
| | - John Hintze
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark
| | - Zilu Ye
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark
| | - Shifa Jebari
- Biofisika Institute (UPV/EHU, CSIC), Departamento de Bioquímica, Universidad del País Vasco, Bilbao, 48080, Spain
| | - Daniel B Andersen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark
| | - Hiren J Joshi
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark
| | - Tongzhong Ju
- Office of Biotechnology Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Jens P Goetze
- Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, DK-2100, Copenhagen O, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark
| | - Cesar Martin
- Office of Biotechnology Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Mette M Rosenkilde
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark
| | - Christoffer K Goth
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark
| | - Sergey Y Vakhrushev
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark
| | - Katrine T Schjoldager
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark.
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10
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Xu SFS, Andersen DB, Izarzugaza JMG, Kuhre RE, Holst JJ. In the rat pancreas, somatostatin tonically inhibits glucagon secretion and is required for glucose-induced inhibition of glucagon secretion. Acta Physiol (Oxf) 2020; 229:e13464. [PMID: 32145704 DOI: 10.1111/apha.13464] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 02/28/2020] [Accepted: 03/04/2020] [Indexed: 12/20/2022]
Abstract
AIM It is debated whether the inhibition of glucagon secretion by glucose results from direct effects of glucose on the α-cell (intrinsic regulation) or by paracrine effects exerted by beta- or delta-cell products. METHODS To study this in a more physiological model than isolated islets, we perfused isolated rat pancreases and measured glucagon, insulin and somatostatin secretion in response to graded increases in perfusate glucose concentration (from 3.5 to 4, 5, 6, 7, 8, 10, 12 mmol/L) as well as glucagon responses to blockage/activation of insulin/GABA/somatostatin signalling with or without addition of glucose. RESULTS Glucagon secretion was reduced by about 50% (compared to baseline secretion at 3.5 mmol/L) within minutes after increasing glucose from 4 to 5 mmol/L (P < .01, n = 13). Insulin secretion was increased minimally, but significantly, compared to baseline (3.5 mmol/L) at 4 mmol/L, whereas somatostatin secretion was not significantly increased from baseline until 7 mmol/L. Hereafter secretion of both increased gradually up to 12 mmol/L glucose. Neither recombinant insulin (1 µmol/L), GABA (300 µmol/L) or the insulin-receptor antagonist S961 (at 1 µmol/L) affected basal (3.5 mmol/L) or glucose-induced (5.0 mmol/L) attenuation of glucagon secretion (n = 7-8). Somatostatin-14 attenuated glucagon secretion by ~ 95%, and blockage of somatostatin-receptor (SSTR)-2 or combined blockage of SSTR-2, -3 and -5 by specific antagonists increased glucagon output (at 3.5 mmol/L glucose) and prevented glucose-induced (from 3.5 to 5.0 mmol/L) suppression of secretion. CONCLUSION Somatostatin is a powerful and tonic inhibitor of glucagon secretion from the rat pancreas and is required for glucose to inhibit glucagon secretion.
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Affiliation(s)
- Stella F. S. Xu
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Daniel B. Andersen
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | | | - Rune E. Kuhre
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Jens J. Holst
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
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11
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Eiken A, Fuglsang S, Eiken M, Svane MS, Kuhre RE, Wewer Albrechtsen NJ, Hansen SH, Trammell SAJ, Svenningsen JS, Rehfeld JF, Bojsen-Møller KN, Jørgensen NB, Holst JJ, Madsbad S, Madsen JL, Dirksen C. Bilio-enteric flow and plasma concentrations of bile acids after gastric bypass and sleeve gastrectomy. Int J Obes (Lond) 2020; 44:1872-1883. [PMID: 32317753 DOI: 10.1038/s41366-020-0578-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 03/04/2020] [Accepted: 03/27/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND/OBJECTIVES Bile acids in plasma are elevated after bariatric surgery and may contribute to metabolic improvements, but underlying changes in bile flow are poorly understood. We assessed bilio-enteric flow of bile and plasma bile concentrations in individuals with Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) surgery compared with matched non-surgical controls (CON). SUBJECTS/METHODS Fifteen RYGB, 10 SG and 15 CON underwent 99Tc-mebrofenin cholescintigraphy combined with intake of a high-fat 111In-DTPA-labelled meal and frequent blood sampling. A 75Se-HCAT test was used to assess bile acid retention. RESULTS After RYGB, gallbladder filling was decreased (p = 0.045 versus CON), basal flow of bile into the small intestine increased (p = 0.005), bile acid retention augmented (p = 0.021) and basal bile acid plasma concentrations elevated (p = 0.009). During the meal, foods passed unimpeded through the gastric pouch resulting in almost instant postprandial mixing of bile and foods, but the postprandial rise in plasma bile acids was brief and associated with decreased overall release of fibroblast growth factor-19 (FGF-19) compared with CON (p = 0.033). After SG, bile flow and retention were largely unaltered (p > 0.05 versus CON), but gastric emptying was accelerated (p < 0.001) causing earlier mixture of bile and foods also in this group. Neither basal nor postprandial bile acid concentrations differed between SG and CON. CONCLUSIONS Bilio-enteric bile flow is markedly altered after RYGB resulting in changes in plasma concentrations of bile acids and FGF-19, whereas bile flow and plasma concentrations are largely unaltered after SG.
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Affiliation(s)
- Aleksander Eiken
- Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark
| | - Stefan Fuglsang
- Department of Clinical Physiology and Nuclear Medicine, Centre for Functional Imaging and Research, Hvidovre Hospital, Hvidovre, Denmark
| | - Markus Eiken
- Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark
| | - Maria S Svane
- Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark
| | - Rune E Kuhre
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department. of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark
| | - Svend H Hansen
- Department. of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark
| | - Samuel A J Trammell
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens S Svenningsen
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens F Rehfeld
- Department. of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark
| | | | - Nils B Jørgensen
- Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark
| | - Jens J Holst
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sten Madsbad
- Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark
| | - Jan L Madsen
- Department of Clinical Physiology and Nuclear Medicine, Centre for Functional Imaging and Research, Hvidovre Hospital, Hvidovre, Denmark
| | - Carsten Dirksen
- Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark.
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12
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Modvig IM, Andersen DB, Grunddal KV, Kuhre RE, Martinussen C, Christiansen CB, Ørskov C, Larraufie P, Kay RG, Reimann F, Gribble FM, Hartmann B, Bojsen-Møller KN, Madsbad S, Wewer Albrechtsen NJ, Holst JJ. Secretin release after Roux-en-Y gastric bypass reveals a population of glucose-sensitive S cells in distal small intestine. Int J Obes (Lond) 2020; 44:1859-1871. [PMID: 32015474 PMCID: PMC7445113 DOI: 10.1038/s41366-020-0541-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 12/17/2019] [Accepted: 01/16/2020] [Indexed: 11/09/2022]
Abstract
OBJECTIVES Gastrointestinal hormones contribute to the beneficial effects of Roux-en-Y gastric bypass surgery (RYGB) on glycemic control. Secretin is secreted from duodenal S cells in response to low luminal pH, but it is unknown whether its secretion is altered after RYGB and if secretin contributes to the postoperative improvement in glycemic control. We hypothesized that secretin secretion increases after RYGB as a result of the diversion of nutrients to more distal parts of the small intestine, and thereby affects islet hormone release. METHODS A specific secretin radioimmunoassay was developed, evaluated biochemically, and used to quantify plasma concentrations of secretin in 13 obese individuals before, 1 week after, and 3 months after RYGB. Distribution of secretin and its receptor was assessed by RNA sequencing, mass-spectrometry and in situ hybridization in human and rat tissues. Isolated, perfused rat intestine and pancreas were used to explore the molecular mechanism underlying glucose-induced secretin secretion and to study direct effects of secretin on glucagon, insulin, and somatostatin secretion. Secretin was administered alone or in combination with GLP-1 to non-sedated rats to evaluate effects on glucose regulation. RESULTS Plasma postprandial secretin was more than doubled in humans after RYGB (P < 0.001). The distal small intestine harbored secretin expressing cells in both rats and humans. Glucose increased the secretion of secretin in a sodium-glucose cotransporter dependent manner when administered to the distal part but not into the proximal part of the rat small intestine. Secretin stimulated somatostatin secretion (fold change: 1.59, P < 0.05) from the perfused rat pancreas but affected neither insulin (P = 0.2) nor glucagon (P = 0.97) secretion. When administered to rats in vivo, insulin secretion was attenuated and glucagon secretion increased (P = 0.04), while blood glucose peak time was delayed (from 15 to 45 min) and gastric emptying time prolonged (P = 0.004). CONCLUSIONS Glucose-sensing secretin cells located in the distal part of the small intestine may contribute to increased plasma concentrations observed after RYGB. The metabolic role of the distal S cells warrants further studies.
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Affiliation(s)
- Ida M Modvig
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Daniel B Andersen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kaare V Grunddal
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Charlotte B Christiansen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Cathrine Ørskov
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Pierre Larraufie
- Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Richard G Kay
- Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Frank Reimann
- Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Fiona M Gribble
- Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Sten Madsbad
- Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark
| | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark. .,Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark. .,Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark. .,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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13
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Christiansen CB, Lind SJ, Svendsen B, Balk-Møller E, Dahlby T, Kuhre RE, Hartmann B, Mandrup-Poulsen T, Deacon CF, Wewer Albrechtsen NJ, Holst JJ. Acute administration of interleukin-6 does not increase secretion of glucagon-like peptide-1 in mice. Physiol Rep 2019; 6:e13788. [PMID: 29981198 PMCID: PMC6035335 DOI: 10.14814/phy2.13788] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 06/14/2018] [Accepted: 06/15/2018] [Indexed: 01/01/2023] Open
Abstract
Interleukin 6 (IL‐6) is a cytokine secreted from skeletal muscle in response to exercise which, based on animal and cell studies, has been suggested to contribute to glucose metabolism by increasing secretion of the incretin hormone glucagon‐like peptide‐1 (GLP‐1) and affecting secretion of insulin and glucagon from the pancreatic islets. We investigated the effect of IL‐6 on GLP‐1 secretion in GLP‐1 producing cells (GLUTag) and using the perfused mouse small intestine (harboring GLP‐1 producing cells). Furthermore, the direct effect of IL‐6 on insulin and glucagon secretion was studied using isolated perfused mouse pancreas. Incubating GLUTag cells with 1000 ng/mL of IL‐6 for 2 h did not significantly increase secretion of GLP‐1 whereas 10 mmol/L glucose (positive control) did. Similarly, IL‐6 (100 ng/mL) had no effect on GLP‐1 secretion from perfused mouse small intestine whereas bombesin (positive control) increased secretion. Finally, administering IL‐6 (100 ng/mL) to perfused mouse pancreases did not significantly increase insulin or glucagon secretion regardless of perfusate glucose levels (3.5 vs. 12 mmol/L glucose). Acute effects of IL‐6 therefore do not seem to include a stimulatory effect on GLP‐1 secretion in mice.
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Affiliation(s)
- Charlotte B Christiansen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sara J Lind
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Berit Svendsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Emilie Balk-Møller
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tina Dahlby
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Mandrup-Poulsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Carolyn F Deacon
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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14
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Vestergaard ET, Hjelholt AJ, Kuhre RE, Møller N, Larraufie P, Gribble FM, Reimann F, Jessen N, Holst JJ, Jørgensen JOL. Acipimox Acutely Increases GLP-1 Concentrations in Overweight Subjects and Hypopituitary Patients. J Clin Endocrinol Metab 2019; 104:2581-2592. [PMID: 30726969 PMCID: PMC7212086 DOI: 10.1210/jc.2018-02503] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 02/01/2019] [Indexed: 12/25/2022]
Abstract
CONTEXT Glucagon-like peptide-1 (GLP-1) is an incretin hormone used therapeutically in type 2 diabetes and obesity. The interplay between ambient free fatty acids (FFAs) and GLP-1 remains unclear. Acipimox suppresses adipose tissue lipolysis via activation of the PUMA-G (also known as HCA2 and GPR109a) receptor. OBJECTIVE To investigate whether lowering of serum FFA level with acipimox affects GLP-1 secretion. DESIGN Two randomized crossover studies were performed in human subjects. Rat intestine was perfused intra-arterially and intraluminally, and l-cells were incubated with acipimox. PARTICIPANTS The participants were healthy overweight subjects and hypopituitary adult patients. INTERVENTIONS The overweight participants received acipimox 250 mg 60 minutes before an oral glucose test. The hypopituitary patients received acipimox 250 mg 12, 9, and 2 hours before and during the metabolic study day, when they were studied in the basal state and during a hyperinsulinemic euglycemic clamp. RESULTS Acipimox suppressed FFA but did not affect insulin in the clinical trials. In overweight subjects, the GLP-1 increase after the oral glucose tolerance test (area under the curve) was more than doubled [4119 ± 607 pmol/L × min (Acipimox) vs 1973 ± 375 pmol/L × min (control), P = 0.004]. In hypopituitary patients, acipimox improved insulin sensitivity (4.7 ± 0.8 mg glucose/kg/min (Acipimox) vs 3.1 ± 0.5 mg glucose/kg/min (control), P = 0.005], and GLP-1 concentrations increased ~40%. An inverse correlation between FFA and GLP-1 concentrations existed in both trials. In rat intestine, acipimox did not affect GLP-1 secretion, and l-cells did not consistently express the putative receptor for acipimox. CONCLUSIONS Acipimox treatment increases systemic GLP-1 levels in both obese subjects and hypopituitary patients. Our in vitro data indicate that the underlying mechanisms are indirect.
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Affiliation(s)
- Esben Thyssen Vestergaard
- Medical Research Laboratories Aarhus University, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
- Department of Pediatrics, Randers Regional Hospital, 8930 Randers
| | - Astrid Johanneson Hjelholt
- Medical Research Laboratories Aarhus University, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
- Department of Diabetes and Endocrinology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
| | - Rune E. Kuhre
- Department of Biomedical Sciences and NNF Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Niels Møller
- Medical Research Laboratories Aarhus University, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
- Department of Diabetes and Endocrinology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
| | - Pierre Larraufie
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, CB2 0QQ, UK
| | - Fiona M. Gribble
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, CB2 0QQ, UK
| | - Frank Reimann
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, CB2 0QQ, UK
| | - Niels Jessen
- Medical Research Laboratories Aarhus University, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
- Research Laboratory for Biochemical Pathology, Aarhus University Hospital, 8000 Aarhus C, Denmark
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark
- Steno Diabetes Centre Aarhus, Aarhus University Hospital, Denmark
| | - Jens Juul Holst
- Department of Biomedical Sciences and NNF Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens Otto Lunde Jørgensen
- Medical Research Laboratories Aarhus University, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
- Department of Diabetes and Endocrinology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
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15
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Kuhre RE, Ghiasi SM, Adriaenssens AE, Wewer Albrechtsen NJ, Andersen DB, Aivazidis A, Chen L, Mandrup-Poulsen T, Ørskov C, Gribble FM, Reimann F, Wierup N, Tyrberg B, Holst JJ. No direct effect of SGLT2 activity on glucagon secretion. Diabetologia 2019; 62:1011-1023. [PMID: 30903205 PMCID: PMC7212061 DOI: 10.1007/s00125-019-4849-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Accepted: 02/12/2019] [Indexed: 02/03/2023]
Abstract
AIMS/HYPOTHESIS Sodium-glucose cotransporter (SGLT) 2 inhibitors constitute a new class of glucose-lowering drugs, but they increase glucagon secretion, which may counteract their glucose-lowering effect. Previous studies using static incubation of isolated human islets or the glucagon-secreting cell line α-TC1 suggested that this results from direct inhibition of alpha cell SGLT1/2-activity. The aim of this study was to test whether the effects of SGLT2 on glucagon secretion demonstrated in vitro could be reproduced in a more physiological setting. METHODS We explored the effect of SGLT2 activity on glucagon secretion using isolated perfused rat pancreas, a physiological model for glucagon secretion. Furthermore, we investigated Slc5a2 (the gene encoding SGLT2) expression in rat islets as well as in mouse and human islets and in mouse and human alpha, beta and delta cells to test for potential inter-species variations. SGLT2 protein content was also investigated in mouse, rat and human islets. RESULTS Glucagon output decreased three- to fivefold within minutes of shifting from low (3.5 mmol/l) to high (10 mmol/l) glucose (4.0 ± 0.5 pmol/15 min vs 1.3 ± 0.3 pmol/15 min, p < 0.05). The output was unaffected by inhibition of SGLT1/2 with dapagliflozin or phloridzin or by addition of the SGLT1/2 substrate α-methylglucopyranoside, whether at low or high glucose concentrations (p = 0.29-0.99). Insulin and somatostatin secretion (potential paracrine regulators) was also unaffected. Slc5a2 expression and SGLT2 protein were marginal or below detection limit in rat, mouse and human islets and in mouse and human alpha, beta and delta cells. CONCLUSIONS/INTERPRETATION Our combined data show that increased plasma glucagon during SGLT2 inhibitor treatment is unlikely to result from direct inhibition of SGLT2 in alpha cells, but instead may occur downstream of their blood glucose-lowering effects.
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Affiliation(s)
- Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Seyed M Ghiasi
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
- Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Alice E Adriaenssens
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark
| | - Daniel B Andersen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Alexander Aivazidis
- Translational Science, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Lihua Chen
- Translational Science, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Thomas Mandrup-Poulsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
| | - Cathrine Ørskov
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
| | - Fiona M Gribble
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Frank Reimann
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Nils Wierup
- Department of Experimental Medical Science, Faculty of Medicine, Lund University Diabetes Centre, Lund, Sweden
| | - Björn Tyrberg
- Translational Science, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark.
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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16
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Modvig IM, Kuhre RE, Holst JJ. Peptone-mediated glucagon-like peptide-1 secretion depends on intestinal absorption and activation of basolaterally located Calcium-Sensing Receptors. Physiol Rep 2019; 7:e14056. [PMID: 31020803 PMCID: PMC6482282 DOI: 10.14814/phy2.14056] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/15/2019] [Accepted: 03/16/2019] [Indexed: 01/13/2023] Open
Abstract
Protein intake robustly stimulates the secretion of the incretin hormone, glucagon-like peptide-1 (GLP-1) but the molecular mechanisms involved are not well understood. In particular, it is unknown whether proteins stimulate secretion by activation of luminal or basolateral sensors. We characterized the mechanisms using a physiologically relevant model - the isolated perfused proximal rat small intestine. Intraluminal protein hydrolysates derived from meat (peptone; 50 mg/mL) increased GLP-1 secretion 2.3-fold (from a basal secretion of 110 ± 28 fmol/min). The sensory mechanisms underlying the response depended on di/tripeptide uptake through Peptide Transporter 1 (PepT1) and subsequent basolateral activation of the amino acid sensing receptor, Calcium-Sensing Receptor (CaSR), since inhibition of PepT1 as well as CaSR both attenuated the peptone-induced GLP-1 response. Supporting this, intraluminal peptones were absorbed efficiently by the perfused intestine (resulting in increased amino acid concentrations in the venous effluent) and infusion of amino acids robustly stimulated GLP-1 secretion. Inhibitors of voltage-gated L-type Ca2+ channels had no effect on secretion suggesting that peptone-mediated GLP-1 secretion is not mediated by L-cell depolarization with subsequent opening of these channels. Specific targeting of CaSR could serve as a target to stimulate the endogenous secretion of GLP-1.
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Affiliation(s)
- Ida M. Modvig
- Department of Biomedical SciencesNNF Center for Basic Metabolic ResearchFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Rune E. Kuhre
- Department of Biomedical SciencesNNF Center for Basic Metabolic ResearchFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Jens Juul Holst
- Department of Biomedical SciencesNNF Center for Basic Metabolic ResearchFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
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17
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18
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Kuhre RE, Christiansen CB, Saltiel MY, Wewer Albrechtsen NJ, Holst JJ. On the relationship between glucose absorption and glucose-stimulated secretion of GLP-1, neurotensin, and PYY from different intestinal segments in the rat. Physiol Rep 2018; 5. [PMID: 29199179 PMCID: PMC5727272 DOI: 10.14814/phy2.13507] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 10/13/2017] [Accepted: 10/26/2017] [Indexed: 12/13/2022] Open
Abstract
Ingested glucose powerfully stimulates the secretion of appetite‐ and metabolism‐regulating peptide hormones from the gut – including glucagon‐like peptide‐1 (GLP‐1), neurotensin (NT), and polypeptide YY (PYY). However, the regional origin of these secretions after glucose stimulation is not well characterized, and it remains uncertain how their secretion is related to glucose absorption. We isolated and perfused either the upper (USI) or the lower (LSI) small intestine or the colon from rats and investigated concomitant glucose absorption and secretory profiles of GLP‐1, NT, and PYY. In the USI and LSI luminal glucose (20%, w/v) increased GLP‐1 and NT secretion five to eightfold compared to basal secretion. Compared to the USI, basal and stimulated GLP‐1 secretion from the colon was 8–10 times lower and no NT secretion was detected. Luminal glucose stimulated secretion of PYY four to fivefold from the LSI and from the USI and colon, but the responses in the USI and colon were 5‐ to 15‐fold lower than in the LSI. Glucose was absorbed to a comparable extent in the USI and LSI by mechanisms that partly depended on both SGLT1 and GLUT2 activity, whereas the absorption in the colon was 80–90% lower. The absorption rates were, however, similar when adjusted for segmental length. Glucose absorption rates and NT, PYY and in particular GLP‐1 secretion were strongly correlated (P < 0.05). Our results indicate that the rate of secretion of GLP‐1, NT, and PYY in response to glucose, regardless of the involved molecular machinery, is predominantly regulated by the rate of glucose absorption.
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Affiliation(s)
- Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Charlotte B Christiansen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Monika Y Saltiel
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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19
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Kuhre RE, Wewer Albrechtsen NJ, Larsen O, Jepsen SL, Balk-Møller E, Andersen DB, Deacon CF, Schoonjans K, Reimann F, Gribble FM, Albrechtsen R, Hartmann B, Rosenkilde MM, Holst JJ. Bile acids are important direct and indirect regulators of the secretion of appetite- and metabolism-regulating hormones from the gut and pancreas. Mol Metab 2018; 11:84-95. [PMID: 29656109 PMCID: PMC6001409 DOI: 10.1016/j.molmet.2018.03.007] [Citation(s) in RCA: 114] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/03/2018] [Accepted: 03/13/2018] [Indexed: 02/06/2023] Open
Abstract
Objective Bile acids (BAs) facilitate fat absorption and may play a role in glucose and metabolism regulation, stimulating the secretion of gut hormones. The relative importance and mechanisms involved in BA-stimulated secretion of appetite and metabolism regulating hormones from the gut and pancreas is not well described and was the purpose of this study. Methods The effects of bile acids on the secretion of gut and pancreatic hormones was studied in rats and compared to the most well described nutritional secretagogue: glucose. The molecular mechanisms that underlie the secretion was studied by isolated perfused rat and mouse small intestine and pancreas preparations and supported by immunohistochemistry, expression analysis, and pharmacological studies. Results Bile acids robustly stimulate secretion of not only the incretin hormones, glucose-dependent insulinotropic peptide (GIP), and glucagon-like peptide-1 (GLP-1), but also glucagon and insulin in vivo, to levels comparable to those resulting from glucose stimulation. The mechanisms of GLP-1, neurotensin, and peptide YY (PYY) secretion was secondary to intestinal absorption and depended on activation of basolateral membrane Takeda G-protein receptor 5 (TGR5) receptors on the L-cells in the following order of potency: Lithocholic acid (LCA) >Deoxycholicacid (DCA)>Chenodeoxycholicacid (CDCA)> Cholic acid (CA). Thus BAs did not stimulate secretion of GLP-1 and PYY from perfused small intestine in TGR5 KO mice but stimulated robust responses in wild type littermates. TGR5 is not expressed on α-cells or β-cells, and BAs had no direct effects on glucagon or insulin secretion from the perfused pancreas. Conclusion BAs should be considered not only as fat emulsifiers but also as important regulators of appetite- and metabolism-regulating hormones by activation of basolateral intestinal TGR5. Bile acids stimulate the secretion of metabolism-regulating hormones from the gut. Bile acids stimulate secretion of gut hormones to a similar extent as glucose. Activation of basolateral TGR5 receptors mediates the responses. Bile acids stimulate glucagon and insulin secretion, but only indirectly. Bile acids should be regarded as important regulators of blood glucose and metabolism.
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Affiliation(s)
- Rune E Kuhre
- Department of Biomedical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Olav Larsen
- Department of Biomedical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Sara L Jepsen
- Department of Biomedical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Emilie Balk-Møller
- Department of Biomedical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Daniel B Andersen
- Department of Biomedical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Carolyn F Deacon
- Department of Biomedical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Kristina Schoonjans
- Laboratory of Metabolic Signaling, Ecole Polytechnique Fédérale de Lausanne, Station 15, CH-1015, Lausanne, Switzerland
| | - Frank Reimann
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, CB2 0QQ, United Kingdom
| | - Fiona M Gribble
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, CB2 0QQ, United Kingdom
| | - Reidar Albrechtsen
- Department of Biomedical Sciences, and Biotech Research and Innovation Centre (BRIC), University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Mette M Rosenkilde
- Department of Biomedical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark; NNF Center for Basic Metabolic Research, University of Copenhagen, DK-2200, Copenhagen, Denmark.
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20
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Wewer Albrechtsen NJ, Albrechtsen R, Bremholm L, Svendsen B, Kuhre RE, Poulsen SS, Christiansen CB, Jensen EP, Janus C, Hilsted L, Deacon CF, Hartmann B, Holst JJ. Glucagon-like Peptide 1 Receptor Signaling in Acinar Cells Causes Growth-Dependent Release of Pancreatic Enzymes. Cell Rep 2017; 17:2845-2856. [PMID: 27974199 DOI: 10.1016/j.celrep.2016.11.051] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 10/31/2016] [Accepted: 11/15/2016] [Indexed: 12/19/2022] Open
Abstract
Incretin-based therapies are widely used for type 2 diabetes and now also for obesity, but they are associated with elevated plasma levels of pancreatic enzymes and perhaps a modestly increased risk of acute pancreatitis. However, little is known about the effects of the incretin hormone glucagon-like peptide 1 (GLP-1) on the exocrine pancreas. Here, we identify GLP-1 receptors on pancreatic acini and analyze the impact of receptor activation in humans, rodents, isolated acini, and cell lines from the exocrine pancreas. GLP-1 did not directly stimulate amylase or lipase release. However, we saw that GLP-1 induces phosphorylation of the epidermal growth factor receptor and activation of Foxo1, resulting in cell growth with concomitant enzyme release. Our work uncovers GLP-1-induced signaling pathways in the exocrine pancreas and suggests that increases in amylase and lipase levels in subjects treated with GLP-1 receptor agonists reflect adaptive growth rather than early-stage pancreatitis.
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Affiliation(s)
- Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Reidar Albrechtsen
- Department of Biomedical Sciences and Biotech Research and Innovation Centre (BRIC), University of Copenhagen, 2200 Copenhagen, Denmark
| | - Lasse Bremholm
- Department of Surgery, Zealand University Hospital, Lykkebækvej 1, 4600 Køge, Denmark
| | - Berit Svendsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Steen S Poulsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Charlotte B Christiansen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Elisa P Jensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Charlotte Janus
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Linda Hilsted
- Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Carolyn F Deacon
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark.
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21
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Windeløv JA, Wewer Albrechtsen NJ, Kuhre RE, Jepsen SL, Hornburg D, Pedersen J, Jensen EP, Galsgaard KD, Winther-Sørensen M, Ørgaard A, Deacon CF, Mann M, Kissow H, Hartmann B, Holst JJ. Why is it so difficult to measure glucagon-like peptide-1 in a mouse? Diabetologia 2017; 60:2066-2075. [PMID: 28669086 DOI: 10.1007/s00125-017-4347-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 05/19/2017] [Indexed: 02/08/2023]
Abstract
AIMS/HYPOTHESIS In humans, glucagon-like peptide-1 (GLP-1) is rapidly degraded by dipeptidyl peptidase-4 to a relatively stable metabolite, GLP-1(9-36)NH2, which allows measurement of GLP-1 secretion. However, little is known about the kinetics of the GLP-1 metabolite in mice. We hypothesised that the GLP-1 metabolite is rapidly degraded in this species by neutral endopeptidase(s) (NEP[s]). METHODS We administered glucose, mixed meal or water orally to 256 mice, and took blood samples before and 2, 6, 10, 20, 30, 60 or 90 min after stimulation. To study the metabolism of the GLP-1 metabolite, i.v. GLP-1(9-36)NH2 (800 fmol) or saline (154 mmol/l NaCl) was administered to 160 mice, some of which had a prior injection of a selective NEP 24.11 ± inhibitor (candoxatril, 5 mg/kg) or saline. Blood was collected before and 1, 2, 4 and 12 min after GLP-1/saline injection. Plasma GLP-1 levels were analysed using a customised single-site C-terminal ELISA, two different two-site ELISAs and MS. RESULTS GLP-1 secretion profiles after oral glucose administration differed markedly when assayed by C-terminal ELISA compared with sandwich ELISAs, with the former showing a far higher peak value and AUC. In mice injected with GLP-1(9-36)NH2, immunoreactive GLP-1 plasma levels peaked at approximately 75 pmol/l at 1 min when measured with sandwich ELISAs, returning to baseline (~20 pmol/l) after 12 min, but remained elevated using the C-terminal ELISA (~90 pmol/l at 12 min). NEP 24.11 inhibition by candoxatril significantly attenuated GLP-1(9-36)NH2 degradation in vivo and in vitro. MS identified GLP-1 fragments consistent with NEP 24.11 degradation. CONCLUSIONS/INTERPRETATION In mice, the GLP-1 metabolite is eliminated within a few minutes owing to endoproteolytic cleavage by NEP 24.11. Therefore, accurate measurement of GLP-1 secretion in mice requires assays for NEP 24.11 metabolites. Conventional sandwich ELISAs are inadequate because of endoproteolytic cleavage of the dipeptidyl peptidase-4-generated metabolite.
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Affiliation(s)
- Johanne A Windeløv
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sara L Jepsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Daniel Hornburg
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jens Pedersen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Elisa P Jensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Katrine D Galsgaard
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Marie Winther-Sørensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anne Ørgaard
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Carolyn F Deacon
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Matthias Mann
- Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Hannelouise Kissow
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark.
- NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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22
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Wewer Albrechtsen NJ, Asmar A, Jensen F, Törang S, Simonsen L, Kuhre RE, Asmar M, Veedfald S, Plamboeck A, Knop FK, Vilsbøll T, Madsbad S, Nauck MA, Deacon CF, Bülow J, Holst JJ, Hartmann B. A sandwich ELISA for measurement of the primary glucagon-like peptide-1 metabolite. Am J Physiol Endocrinol Metab 2017; 313:E284-E291. [PMID: 28420649 DOI: 10.1152/ajpendo.00005.2017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 03/21/2017] [Accepted: 04/06/2017] [Indexed: 11/22/2022]
Abstract
Glucagon-like peptide-1 (GLP-1) is an incretin hormone secreted from the gastrointestinal tract. It is best known for its glucose-dependent insulinotropic effects. GLP-1 is secreted in its intact (active) form (7-36NH2) but is rapidly degraded by the dipeptidyl peptidase 4 (DPP-4) enzyme, converting >90% to the primary metabolite (9-36NH2) before reaching the targets via the circulation. Although originally thought to be inactive or antagonistic, GLP-1 9-36NH2 may have independent actions, and it is therefore relevant to be able to measure it. Because reliable assays were not available, we developed a sandwich ELISA recognizing both GLP-1 9-36NH2 and nonamidated GLP-1 9-37. The ELISA was validated using analytical assay validation guidelines and by comparing it to a subtraction-based method, hitherto employed for estimation of GLP-1 9-36NH2 Its accuracy was evaluated from measurements of plasma obtained during intravenous infusions (1.5 pmol × kg-1 × min-1) of GLP-1 7-36NH2 in healthy subjects and patients with type 2 diabetes. Plasma levels of the endogenous GLP-1 metabolite increased during a meal challenge in patients with type 2 diabetes, and treatment with a DPP-4 inhibitor fully blocked its formation. Accurate measurements of the GLP-1 metabolite may contribute to understanding its physiology and role of GLP-1 in diabetes.
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Affiliation(s)
- Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ali Asmar
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Frederik Jensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Signe Törang
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lene Simonsen
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Meena Asmar
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Simon Veedfald
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Astrid Plamboeck
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Filip K Knop
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tina Vilsbøll
- Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Steno Diabetes Center Copenhagen, University of Copenhagen, Gentofte, Denmark
| | - Sten Madsbad
- Department of Endocrinology, Hvidovre University Hospital, Copenhagen, Denmark; and
| | - Michael A Nauck
- Division of Diabetology, Department of Medicine I, St. Josef Hospital, Ruhr University of Bochum, Bochum, Germany
| | - Carolyn F Deacon
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens Bülow
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark;
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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23
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Saltiel MY, Kuhre RE, Christiansen CB, Eliasen R, Conde-Frieboes KW, Rosenkilde MM, Holst JJ. Sweet Taste Receptor Activation in the Gut Is of Limited Importance for Glucose-Stimulated GLP-1 and GIP Secretion. Nutrients 2017; 9:nu9040418. [PMID: 28441725 PMCID: PMC5409757 DOI: 10.3390/nu9040418] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/11/2017] [Accepted: 04/18/2017] [Indexed: 01/14/2023] Open
Abstract
Glucose stimulates the secretion of the incretin hormones: glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP). It is debated whether the sweet taste receptor (STR) triggers this secretion. We investigated the role of STR activation for glucose-stimulated incretin secretion from an isolated perfused rat small intestine and whether selective STR activation by artificial sweeteners stimulates secretion. Intra-luminal administration of the STR agonists, acesulfame K (3.85% w/v), but not sucralose (1.25% w/v) and stevioside (2.5% w/v), stimulated GLP-1 secretion (acesulfame K: 31 ± 3 pmol/L vs. 21 ± 2 pmol/L, p < 0.05, n = 6). In contrast, intra-arterial administration of sucralose (10 mM) and stevioside (10 mM), but not acesulfame K, stimulated GLP-1 secretion (sucralose: 51 ± 6 pmol/L vs. 34 ± 4 pmol/L, p < 0.05; stevioside: 54 ± 6 pmol/L vs. 32 ± 2 pmol/L, p < 0.05, n = 6), while 0.1 mM and 1 mM sucralose did not affect the secretion. Luminal glucose (20% w/v) doubled GLP-1 and GIP secretion, but basolateral STR inhibition by gurmarin (2.5 µg/mL) or the inhibition of the transient receptor potential cation channel 5 (TRPM5) by triphenylphosphine oxide (TPPO) (100 µM) did not attenuate the responses. In conclusion, STR activation does not drive GIP/GLP-1 secretion itself, nor does it have a role for glucose-stimulated GLP-1 or GIP secretion.
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Affiliation(s)
- Monika Y Saltiel
- NNF Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej, DK-2200, Copenhagen N, Denmark.
| | - Rune E Kuhre
- NNF Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej, DK-2200, Copenhagen N, Denmark.
| | - Charlotte B Christiansen
- NNF Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej, DK-2200, Copenhagen N, Denmark.
| | - Rasmus Eliasen
- Protein & Peptide Chemistry, Novo Nordisk A/S, Novo Nordisk Park, DK-2760 Måløv, Denmark.
| | | | - Mette M Rosenkilde
- NNF Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej, DK-2200, Copenhagen N, Denmark.
| | - Jens J Holst
- NNF Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej, DK-2200, Copenhagen N, Denmark.
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24
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Nielsen S, Svane MS, Kuhre RE, Clausen TR, Kristiansen VB, Rehfeld JF, Holst JJ, Madsbad S, Bojsen-Moller KN. Chenodeoxycholic acid stimulates glucagon-like peptide-1 secretion in patients after Roux-en-Y gastric bypass. Physiol Rep 2017; 5:5/3/e13140. [PMID: 28202805 PMCID: PMC5309580 DOI: 10.14814/phy2.13140] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 01/05/2017] [Accepted: 01/06/2017] [Indexed: 12/31/2022] Open
Abstract
Postprandial secretion of glucagon‐like peptide‐1 (GLP‐1) is enhanced after Roux‐en‐Y gastric bypass (RYGB), but the precise molecular mechanisms explaining this remain poorly understood. Plasma concentrations of bile acids (BAs) increase after RYGB, and BAs may act as molecular enhancers of GLP‐1 secretion through activation of TGR5‐receptors. We aimed to evaluate GLP‐1 secretion after oral administration of the primary bile acid chenodeoxycholic acid (CDCA) and the secondary bile acid ursodeoxycholic acid (UDCA) (which are available for oral use) in RYGB‐operated participants. Eleven participants (BMI 29.1 ± 1.2, age 37.0 ± 3.2 years, time from RYGB 32.3 ± 1.1 months, weight loss after RYGB 37.0 ± 3.1 kg) were studied in a placebo‐controlled, crossover‐study. On three different days, participants ingested (1) placebo (water), (2) UDCA 750 mg, (3) CDCA 1250 mg (highest recommended doses). Oral intake of CDCA increased plasma concentrations of GLP‐1, C‐peptide, glucagon, peptide YY, neurotensin, total bile acids, and fibroblast growth factor 19 significantly compared with placebo (all P < 0.05 for peak and positive incremental area‐under‐the‐curve (piAUC)). All plasma hormone concentrations were unaffected by UDCA. Neither UDCA nor CDCA changed glucose, cholecystokinin or glucose‐dependent insulinotropic polypeptide (GIP) concentrations. In conclusion, our findings demonstrate that the primary bile acid chenodeoxycholic acid is able to enhance secretion of gut hormones when administered orally in RYGB‐operated patients—even in the absence of nutrients.
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Affiliation(s)
- Signe Nielsen
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark.,NNF Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Maria S Svane
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark.,NNF Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Rune E Kuhre
- NNF Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Viggo B Kristiansen
- Department of Surgical Gastroenterology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Jens F Rehfeld
- Department of Clinical Biochemistry, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Jens J Holst
- NNF Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sten Madsbad
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark.,NNF Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Kirstine N Bojsen-Moller
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark .,NNF Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
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25
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Abstract
The proglucagon-derived peptide hormone, glucagon, comprises 29 amino acids. Its secretion from the pancreatic α cells is regulated by several factors. Glucagon increases blood glucose levels through gluconeogenesis and glycogenolysis. Elevated plasma concentrations of glucagon, hyperglucagonemia, may contribute to diabetes. However, hyperglucagonemia is also observed in other clinical conditions than diabetes, including nonalcoholic fatty liver disease, glucagon-producing tumors and after gastric bypass surgery. Here, we review the current literature on hyperglucagonemia in disease with a particular focus on diabetes, and finally speculate that the primary physiological importance of glucagon may not reside in glucose homeostasis but in regulation of amino acid metabolism exerted via a hitherto unrecognized hepato-pancreatic feedback loop.
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Affiliation(s)
- Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health & Medical Sciences, University of Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health & Medical Sciences, University of Copenhagen, Denmark
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health & Medical Sciences, University of Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health & Medical Sciences, University of Copenhagen, Denmark
| | - Jens Pedersen
- Department of Biomedical Sciences, Faculty of Health & Medical Sciences, University of Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health & Medical Sciences, University of Copenhagen, Denmark
| | - Filip K Knop
- Department of Biomedical Sciences, Faculty of Health & Medical Sciences, University of Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health & Medical Sciences, University of Copenhagen, Denmark.,Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health & Medical Sciences, University of Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health & Medical Sciences, University of Copenhagen, Denmark
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26
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Wewer Albrechtsen NJ, Kuhre RE, Windeløv JA, Ørgaard A, Deacon CF, Kissow H, Hartmann B, Holst JJ. Dynamics of glucagon secretion in mice and rats revealed using a validated sandwich ELISA for small sample volumes. Am J Physiol Endocrinol Metab 2016; 311:E302-9. [PMID: 27245336 DOI: 10.1152/ajpendo.00119.2016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Accepted: 05/26/2016] [Indexed: 12/28/2022]
Abstract
Glucagon is a metabolically important hormone, but many aspects of its physiology remain obscure, because glucagon secretion is difficult to measure in mice and rats due to methodological inadequacies. Here, we introduce and validate a low-volume, enzyme-linked immunosorbent glucagon assay according to current analytical guidelines, including tests of sensitivity, specificity, and accuracy, and compare it, using the Bland-Altman algorithm and size-exclusion chromatography, with three other widely cited assays. After demonstrating adequate performance of the assay, we measured glucagon secretion in response to intravenous glucose and arginine in anesthetized mice (isoflurane) and rats (Hypnorm/midazolam). Glucose caused a long-lasting suppression to very low values (1-2 pmol/l) within 2 min in both species. Arginine stimulated secretion 8- to 10-fold in both species, peaking at 1-2 min and returning to basal levels at 6 min (mice) and 12 min (rats). d-Mannitol (osmotic control) was without effect. Ketamine/xylazine anesthesia in mice strongly attenuated (P < 0.01) α-cell responses. Chromatography of pooled plasma samples confirmed the accuracy of the assay. In conclusion, dynamic analysis of glucagon secretion in rats and mice with the novel accurate sandwich enzyme-linked immunosorbent assay revealed extremely rapid and short-lived responses to arginine and rapid and profound suppression by glucose.
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Affiliation(s)
- Nicolai J Wewer Albrechtsen
- Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark; and Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Rune E Kuhre
- Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark; and Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Johanne A Windeløv
- Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark; and Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Anne Ørgaard
- Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark; and Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Carolyn F Deacon
- Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark; and Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Hannelouise Kissow
- Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark; and
| | - Bolette Hartmann
- Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark; and Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark; and Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
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27
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Wewer Albrechtsen NJ, Hornburg D, Albrechtsen R, Svendsen B, Toräng S, Jepsen SL, Kuhre RE, Hansen M, Janus C, Floyd A, Lund A, Vilsbøll T, Knop FK, Vestergaard H, Deacon CF, Meissner F, Mann M, Holst JJ, Hartmann B. Oxyntomodulin Identified as a Marker of Type 2 Diabetes and Gastric Bypass Surgery by Mass-spectrometry Based Profiling of Human Plasma. EBioMedicine 2016; 7:112-20. [PMID: 27322465 PMCID: PMC4909640 DOI: 10.1016/j.ebiom.2016.03.034] [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] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/02/2016] [Accepted: 03/21/2016] [Indexed: 02/03/2023] Open
Abstract
Low-abundance regulatory peptides, including metabolically important gut hormones, have shown promising therapeutic potential. Here, we present a streamlined mass spectrometry-based platform for identifying and characterizing low-abundance regulatory peptides in humans. We demonstrate the clinical applicability of this platform by studying a hitherto neglected glucose- and appetite-regulating gut hormone, namely, oxyntomodulin. Our results show that the secretion of oxyntomodulin in patients with type 2 diabetes is significantly impaired, and that its level is increased by more than 10-fold after gastric bypass surgery. Furthermore, we report that oxyntomodulin is co-distributed and co-secreted with the insulin-stimulating and appetite-regulating gut hormone glucagon-like peptide-1 (GLP-1), is inactivated by the same protease (dipeptidyl peptidase-4) as GLP-1 and acts through its receptor. Thus, oxyntomodulin may participate with GLP-1 in the regulation of glucose metabolism and appetite in humans. In conclusion, this mass spectrometry-based platform is a powerful resource for identifying and characterizing metabolically active low-abundance peptides.
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Affiliation(s)
- Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany; Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
| | - Daniel Hornburg
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Reidar Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Biomedical Sciences and Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Berit Svendsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Signe Toräng
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sara L Jepsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Marie Hansen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Charlotte Janus
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Andrea Floyd
- Department of Surgery, Division of Bariatric Surgery, Køge Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Asger Lund
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Tina Vilsbøll
- Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Filip K Knop
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Henrik Vestergaard
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Carolyn F Deacon
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Felix Meissner
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Matthias Mann
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany; Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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28
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Wewer Albrechtsen NJ, Kuhre RE, Toräng S, Holst JJ. The intestinal distribution pattern of appetite- and glucose regulatory peptides in mice, rats and pigs. BMC Res Notes 2016; 9:60. [PMID: 26830025 PMCID: PMC4736122 DOI: 10.1186/s13104-016-1872-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 01/19/2016] [Indexed: 01/12/2023] Open
Abstract
Background Mice, rats, and pigs are the three most used animal models when studying gastrointestinal peptide hormones;
however their distribution from the duodenum to the distal colon has not been characterized systematically across mice, rats and pigs. We therefore performed a comparative distribution analysis of the tissue content of the major appetite- and glucose regulatory peptides: glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), glucagon-like peptide-1 (GLP-2), oxyntomodulin/glicentin, neurotensin, and peptide YY (PYY) from the duodenum to distal colon in mice (n = 9), rats (n = 9) and pigs (n = 8), using validated radioimmunoassays. Results GLP-1, GLP-2 and oxyntomodulin/glicentin show similar patterns of distribution within the respective species, but for rats and pigs the highest levels were found in the distal small intestine, whereas for the mouse the highest level was found in the distal colon. In rats and pigs, neurotensin was predominantly detected in mid and lower part of the small intestine, while the mouse showed the highest levels in the distal small intestine. In contrast, the distribution of GIP was restricted to the proximal small intestine in all three species. Most surprisingly, in the pig PYY was found in large amounts in the proximal part of the small intestine whereas both rats and mice had undetectable levels until the distal small intestine. Conclusions In summary, the distribution patterns of extractable GIP, GLP-1, GLP-2, oxyntomodulin/glicentin, neurotensin are preserved across species whereas PYY distribution showed marked differences. Electronic supplementary material The online version of this article (doi:10.1186/s13104-016-1872-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nicolai J Wewer Albrechtsen
- NNF Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 12.2, 2200, Copenhagen N, Denmark.
| | - Rune E Kuhre
- NNF Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 12.2, 2200, Copenhagen N, Denmark.
| | - Signe Toräng
- NNF Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 12.2, 2200, Copenhagen N, Denmark.
| | - Jens J Holst
- NNF Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 12.2, 2200, Copenhagen N, Denmark.
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29
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Brighton CA, Rievaj J, Kuhre RE, Glass LL, Schoonjans K, Holst JJ, Gribble FM, Reimann F. Bile Acids Trigger GLP-1 Release Predominantly by Accessing Basolaterally Located G Protein-Coupled Bile Acid Receptors. Endocrinology 2015; 156:3961-70. [PMID: 26280129 PMCID: PMC4606749 DOI: 10.1210/en.2015-1321] [Citation(s) in RCA: 226] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Bile acids are well-recognized stimuli of glucagon-like peptide-1 (GLP-1) secretion. This action has been attributed to activation of the G protein-coupled bile acid receptor GPBAR1 (TGR5), although other potential bile acid sensors include the nuclear farnesoid receptor and the apical sodium-coupled bile acid transporter ASBT. The aim of this study was to identify pathways important for GLP-1 release and to determine whether bile acids target their receptors on GLP-1-secreting L-cells from the apical or basolateral compartment. Using transgenic mice expressing fluorescent sensors specifically in L-cells, we observed that taurodeoxycholate (TDCA) and taurolithocholate (TLCA) increased intracellular cAMP and Ca(2+). In primary intestinal cultures, TDCA was a more potent GLP-1 secretagogue than taurocholate (TCA) and TLCA, correlating with a stronger Ca(2+) response to TDCA. Using small-volume Ussing chambers optimized for measuring GLP-1 secretion, we found that both a GPBAR1 agonist and TDCA stimulated GLP-1 release better when applied from the basolateral than from the luminal direction and that luminal TDCA was ineffective when intestinal tissue was pretreated with an ASBT inhibitor. ASBT inhibition had no significant effect in nonpolarized primary cultures. Studies in the perfused rat gut confirmed that vascularly administered TDCA was more effective than luminal TDCA. Intestinal primary cultures and Ussing chamber-mounted tissues from GPBAR1-knockout mice did not secrete GLP-1 in response to either TLCA or TDCA. We conclude that the action of bile acids on GLP-1 secretion is predominantly mediated by GPBAR1 located on the basolateral L-cell membrane, suggesting that stimulation of gut hormone secretion may include postabsorptive mechanisms.
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Christensen LW, Kuhre RE, Janus C, Svendsen B, Holst JJ. Vascular, but not luminal, activation of FFAR1 (GPR40) stimulates GLP-1 secretion from isolated perfused rat small intestine. Physiol Rep 2015; 3:e12551. [PMID: 26381015 PMCID: PMC4600392 DOI: 10.14814/phy2.12551] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 08/25/2015] [Accepted: 08/29/2015] [Indexed: 12/23/2022] Open
Abstract
Glucagon-like peptide 1 (GLP-1) plays a central role in modern treatment of type 2 diabetes (T2DM) in the form of GLP-1 enhancers and GLP-1 mimetics. An alternative treatment strategy is to stimulate endogenous GLP-1 secretion from enteroendocrine L cells using a targeted approach. The G-protein-coupled receptor, FFAR1 (previously GPR40), expressed on L cells and activated by long-chain fatty acids (LCFAs) is a potential target. A link between FFAR1 activation and GLP-1 secretion has been demonstrated in cellular models and small-molecule FFAR1 agonists have been developed. In this study, we examined the effect of FFAR1 activation on GLP-1 secretion using isolated, perfused small intestines from rats, a physiologically relevant model allowing distinction between direct and indirect effects of FFAR1 activation. The endogenous FFAR1 ligand, linoleic acid (LA), and four synthetic FFAR1 agonists (TAK-875, AMG 837, AM-1638, and AM-5262) were administered through intraluminal and intra-arterial routes, respectively, and dynamic changes in GLP-1 secretion were evaluated. Vascular administration of 10 μmol/L TAK-875, 10 μmol/L AMG 837, 1 μmol/L and 0.1 μmol/L AM-1638, 1 μmol/L AM-6252, and 1 mmol/L LA, all significantly increased GLP-1 secretion compared to basal levels (P < 0.05), whereas luminal administration of LA and FFAR1 agonists was ineffective. Thus, both natural and small-molecule agonists of the FFAR1 receptor appear to require absorption prior to stimulating GLP-1 secretion, indicating that therapies based on activation of nutrient sensing may be more complex than hitherto expected.
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Affiliation(s)
- Louise W Christensen
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute University of Copenhagen, Copenhagen, Denmark
| | - Rune E Kuhre
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute University of Copenhagen, Copenhagen, Denmark
| | - Charlotte Janus
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute University of Copenhagen, Copenhagen, Denmark
| | - Berit Svendsen
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, Panum Institute University of Copenhagen, Copenhagen, Denmark
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31
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Wewer Albrechtsen NJ, Bak MJ, Hartmann B, Christensen LW, Kuhre RE, Deacon CF, Holst JJ. Stability of glucagon-like peptide 1 and glucagon in human plasma. Endocr Connect 2015; 4:50-7. [PMID: 25596009 PMCID: PMC4317691 DOI: 10.1530/ec-14-0126] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 01/16/2015] [Indexed: 01/14/2023]
Abstract
To investigate the stability of glucagon-like peptide 1 (GLP-1) and glucagon in plasma under short- and long-term storage conditions. Pooled human plasma (n=20), to which a dipeptidyl peptidase 4 (DPP4) inhibitor and aprotinin were added, was spiked with synthetic GLP-1 (intact, 7-36NH2 as well as the primary metabolite, GLP-1 9-36NH2) or glucagon. Peptide recoveries were measured in samples kept for 1 and 3 h at room temperature or on ice, treated with various enzyme inhibitors, after up to three thawing-refreezing cycles, and after storage at -20 and -80 °C for up to 1 year. Recoveries were unaffected by freezing cycles or if plasma was stored on ice for up to 3 h, but were impaired when samples stood at RT for more than 1 h. Recovery of intact GLP-1 increased by addition of a DPP4 inhibitor (no ice), but was not further improved by neutral endopeptidase 24.11 inhibitor or an inhibitor cocktail. GLP-1, but not glucagon, was stable for at least 1 year. Surprisingly, the recovery of glucagon was reduced by almost 50% by freezing compared with immediate analysis, regardless of storage time. Plasma handling procedures can significantly influence results of subsequent hormone analysis. Our data support addition of DPP4 inhibitor for GLP-1 measurement as well as cooling on ice of both GLP-1 and glucagon. Freeze-thaw cycles did not significantly affect stability of GLP-1 or glucagon. Long-term storage may affect glucagon levels regardless of storage temperature and results should be interpreted with caution.
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Affiliation(s)
- Nicolai J Wewer Albrechtsen
- NNF Center for Basic Metabolic Research and Department of Biomedical SciencesDepartment of ScienceFaculty of Health Science, University of Copenhagen, Blegdamsvej 3B, 12.2, DK-2200 Copenhagen N, Denmark
| | - Monika J Bak
- NNF Center for Basic Metabolic Research and Department of Biomedical SciencesDepartment of ScienceFaculty of Health Science, University of Copenhagen, Blegdamsvej 3B, 12.2, DK-2200 Copenhagen N, Denmark NNF Center for Basic Metabolic Research and Department of Biomedical SciencesDepartment of ScienceFaculty of Health Science, University of Copenhagen, Blegdamsvej 3B, 12.2, DK-2200 Copenhagen N, Denmark
| | - Bolette Hartmann
- NNF Center for Basic Metabolic Research and Department of Biomedical SciencesDepartment of ScienceFaculty of Health Science, University of Copenhagen, Blegdamsvej 3B, 12.2, DK-2200 Copenhagen N, Denmark
| | - Louise Wulff Christensen
- NNF Center for Basic Metabolic Research and Department of Biomedical SciencesDepartment of ScienceFaculty of Health Science, University of Copenhagen, Blegdamsvej 3B, 12.2, DK-2200 Copenhagen N, Denmark
| | - Rune E Kuhre
- NNF Center for Basic Metabolic Research and Department of Biomedical SciencesDepartment of ScienceFaculty of Health Science, University of Copenhagen, Blegdamsvej 3B, 12.2, DK-2200 Copenhagen N, Denmark
| | - Carolyn F Deacon
- NNF Center for Basic Metabolic Research and Department of Biomedical SciencesDepartment of ScienceFaculty of Health Science, University of Copenhagen, Blegdamsvej 3B, 12.2, DK-2200 Copenhagen N, Denmark
| | - Jens J Holst
- NNF Center for Basic Metabolic Research and Department of Biomedical SciencesDepartment of ScienceFaculty of Health Science, University of Copenhagen, Blegdamsvej 3B, 12.2, DK-2200 Copenhagen N, Denmark
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Abstract
Glucose is an important stimulus for glucagon-like peptide 1 (GLP-1) secretion, but the mechanisms of secretion have not been investigated in integrated physiological models. We studied glucose-stimulated GLP-1 secretion from isolated perfused rat small intestine. Luminal glucose (5% and 20% w/v) stimulated the secretion dose dependently, but vascular glucose was without significant effect at 5, 10, 15, and 25 mmol/L. GLP-1 stimulation by luminal glucose (20%) secretion was blocked by the voltage-gated Ca channel inhibitor, nifedipine, or by hyperpolarization with diazoxide. Luminal administration (20%) of the nonmetabolizable sodium-glucose transporter 1 (SGLT1) substrate, methyl-α-D-glucopyranoside (α-MGP), stimulated release, whereas the SGLT1 inhibitor phloridzin (luminally) abolished responses to α-MGP and glucose. Furthermore, in the absence of luminal NaCl, luminal glucose (20%) did not stimulate a response. Luminal glucose-stimulated GLP-1 secretion was also sensitive to luminal GLUT2 inhibition (phloretin), but in contrast to SGLT1 inhibition, phloretin did not eliminate the response, and luminal glucose (20%) stimulated larger GLP-1 responses than luminal α-MGP in matched concentrations. Glucose transported by GLUT2 may act after metabolization, closing KATP channels similar to sulfonylureas, which also stimulated secretion. Our data indicate that SGLT1 activity is the driving force for glucose-stimulated GLP-1 secretion and that KATP-channel closure is required to stimulate a full-blown glucose-induced response.
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Affiliation(s)
- Rune E Kuhre
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, the Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Charlotte R Frost
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, the Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Berit Svendsen
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, the Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences, the Panum Institute, University of Copenhagen, Copenhagen, Denmark
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Kuhre RE, Gribble FM, Hartmann B, Reimann F, Windeløv JA, Rehfeld JF, Holst JJ. Fructose stimulates GLP-1 but not GIP secretion in mice, rats, and humans. Am J Physiol Gastrointest Liver Physiol 2014; 306:G622-30. [PMID: 24525020 PMCID: PMC3962593 DOI: 10.1152/ajpgi.00372.2013] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 02/01/2014] [Indexed: 01/31/2023]
Abstract
Nutrients often stimulate gut hormone secretion, but the effects of fructose are incompletely understood. We studied the effects of fructose on a number of gut hormones with particular focus on glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). In healthy humans, fructose intake caused a rise in blood glucose and plasma insulin and GLP-1, albeit to a lower degree than isocaloric glucose. Cholecystokinin secretion was stimulated similarly by both carbohydrates, but neither peptide YY3-36 nor glucagon secretion was affected by either treatment. Remarkably, while glucose potently stimulated GIP release, fructose was without effect. Similar patterns were found in the mouse and rat, with both fructose and glucose stimulating GLP-1 secretion, whereas only glucose caused GIP secretion. In GLUTag cells, a murine cell line used as model for L cells, fructose was metabolized and stimulated GLP-1 secretion dose-dependently (EC50 = 0.155 mM) by ATP-sensitive potassium channel closure and cell depolarization. Because fructose elicits GLP-1 secretion without simultaneous release of glucagonotropic GIP, the pathways underlying fructose-stimulated GLP-1 release might be useful targets for type 2 diabetes mellitus and obesity drug development.
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Affiliation(s)
- Rune E Kuhre
- Department of Biomedical Sciences, NNF Centre for Basic Metabolic Research, the Panum Institute, University of Copenhagen, Copenhagen, Denmark
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