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Wang M, Fu X, Du L, Shi F, Huang Z, Yang L. The Inferential Binding Sites of GCGR for Small Molecules Using Protein Dynamic Conformations and Crystal Structures. Int J Mol Sci 2024; 25:8389. [PMID: 39125959 PMCID: PMC11313378 DOI: 10.3390/ijms25158389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 07/23/2024] [Accepted: 07/25/2024] [Indexed: 08/12/2024] Open
Abstract
Glucagon receptor (GCGR) is a class B1 G-protein-coupled receptor that plays a crucial role in maintaining human blood glucose homeostasis and is a significant target for the treatment of type 2 diabetes mellitus (T2DM). Currently, six small molecules (Bay 27-9955, MK-0893, MK-3577, LY2409021, PF-06291874, and LGD-6972) have been tested or are undergoing clinical trials, but only the binding site of MK-0893 has been resolved. To predict binding sites for other small molecules, we utilized both the crystal structure of the GCGR and MK-0893 complex and dynamic conformations. We docked five small molecules and selected the best conformation based on binding mode, docking score, and binding free energy. We performed MD simulations to verify the binding mode of the selected small molecules. Moreover, when selecting conformations, results of competitive binding were referred to. MD simulation indicated that Bay 27-9955 exhibits moderate binding stability in Pocket 3. MK-3577, LY2409021, and PF-06291874 exhibited highly stable binding to Pocket 2, consistent with experimental results. However, LY2409021 may also bind to Pocket 5. Additionally, LGD-6972 exhibited relatively stable binding in Pocket 5. We also conducted structural modifications of LGD-6972 based on the results of MD simulations and predicted its analogues' bioavailability, providing a reference for the study of GCGR small molecules.
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Affiliation(s)
- Mengru Wang
- Department of Pharmacology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, China; (M.W.); (X.F.); (L.D.); (F.S.)
| | - Xulei Fu
- Department of Pharmacology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, China; (M.W.); (X.F.); (L.D.); (F.S.)
| | - Limin Du
- Department of Pharmacology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, China; (M.W.); (X.F.); (L.D.); (F.S.)
| | - Fan Shi
- Department of Pharmacology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, China; (M.W.); (X.F.); (L.D.); (F.S.)
| | - Zichong Huang
- Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou 450001, China;
| | - Linlin Yang
- Department of Pharmacology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, China; (M.W.); (X.F.); (L.D.); (F.S.)
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McGlone ER, Tan TMM. Glucagon-based therapy for people with diabetes and obesity: What is the sweet spot? Peptides 2024; 176:171219. [PMID: 38615717 DOI: 10.1016/j.peptides.2024.171219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 04/09/2024] [Accepted: 04/10/2024] [Indexed: 04/16/2024]
Abstract
People with obesity and type 2 diabetes have a high prevalence of metabolic-associated steatotic liver disease, hyperlipidemia and cardiovascular disease. Glucagon increases hepatic glucose production; it also decreases hepatic fat accumulation, improves lipidemia and increases energy expenditure. Pharmaceutical strategies to antagonize the glucagon receptor improve glycemic outcomes in people with diabetes and obesity, but they increase hepatic steatosis and worsen dyslipidemia. Co-agonism of the glucagon and glucagon-like peptide-1 (GLP-1) receptors has emerged as a promising strategy to improve glycemia in people with diabetes and obesity. Addition of glucagon receptor agonism enhances weight loss, reduces liver fat and ameliorates dyslipidemia. Prior to clinical use, however, further studies are needed to investigate the safety and efficacy of glucagon and GLP-1 receptor co-agonists in people with diabetes and obesity and related conditions, with specific concerns regarding a higher prevalence of gastrointestinal side effects, loss of muscle mass and increases in heart rate. Furthermore, co-agonists with differing ratios of glucagon:GLP-1 receptor activity vary in their clinical effect; the optimum balance is yet to be identified.
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Affiliation(s)
- Emma Rose McGlone
- Department of Surgery and Cancer, Imperial College London, London, UK; Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Tricia M-M Tan
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
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Himuro M, Wakabayashi Y, Taguchi T, Katahira T, Suzuki L, Iida H, Ogihara T, Nishida Y, Sasaki S, Lynn FC, Hiraoka Y, Oshima S, Okamoto R, Fujitani Y, Watada H, Miyatsuka T. Novel time-resolved reporter mouse reveals spatial and transcriptional heterogeneity during alpha cell differentiation. Diabetologia 2024; 67:156-169. [PMID: 37870650 DOI: 10.1007/s00125-023-06028-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 08/25/2023] [Indexed: 10/24/2023]
Abstract
AIMS/HYPOTHESIS Glucagon-expressing pancreatic alpha cells have attracted much attention for their plasticity to transdifferentiate into insulin-producing beta cells; however, it remains unclear precisely when, and from where, alpha cells emerge and what regulates alpha cell fate. We therefore explored the spatial and transcriptional heterogeneity of alpha cell differentiation using a novel time-resolved reporter system. METHODS We established the mouse model, 'Gcg-Timer', in which newly generated alpha cells can be distinguished from more-differentiated cells by their fluorescence. Fluorescence imaging and transcriptome analysis were performed with Gcg-Timer mice during the embryonic and postnatal stages. RESULTS Fluorescence imaging and flow cytometry demonstrated that green fluorescence-dominant cells were present in Gcg-Timer mice at the embryonic and neonatal stages but not after 1 week of age, suggesting that alpha cell neogenesis occurs during embryogenesis and early neonatal stages under physiological conditions. Transcriptome analysis of Gcg-Timer embryos revealed that the mRNAs related to angiogenesis were enriched in newly generated alpha cells. Histological analysis revealed that some alpha cells arise close to the pancreatic ducts, whereas the others arise away from the ducts and adjacent to the blood vessels. Notably, when the glucagon signal was suppressed by genetic ablation or by chemicals, such as neutralising glucagon antibody, green-dominant cells emerged again in adult mice. CONCLUSIONS/INTERPRETATION Novel time-resolved analysis with Gcg-Timer reporter mice uncovered spatiotemporal features of alpha cell neogenesis that will enhance our understanding of cellular identity and plasticity within the islets. DATA AVAILABILITY Raw and processed RNA sequencing data for this study has been deposited in the Gene Expression Omnibus under accession number GSE229090.
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Affiliation(s)
- Miwa Himuro
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yuka Wakabayashi
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Tomomi Taguchi
- Department of Endocrinology, Diabetes and Metabolism, Kitasato University School of Medicine, Sagamihara, Japan
| | - Takehiro Katahira
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Luka Suzuki
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Hitoshi Iida
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Takeshi Ogihara
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yuya Nishida
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Shugo Sasaki
- Diabetes Research Group, BC Children's Hospital Research Institute, Vancouver, BC, Canada
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Francis C Lynn
- Diabetes Research Group, BC Children's Hospital Research Institute, Vancouver, BC, Canada
| | - Yuichi Hiraoka
- Laboratory of Genome Editing for Biomedical Research, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shigeru Oshima
- Department of Gastroenterology and Hepatology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ryuichi Okamoto
- Department of Gastroenterology and Hepatology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yoshio Fujitani
- Laboratory of Developmental Biology & Metabolism, Institute for Molecular & Cellular Regulation, Gunma University, Maebashi, Japan
| | - Hirotaka Watada
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan.
- Center for Identification of Diabetic Therapeutic Targets, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - Takeshi Miyatsuka
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan.
- Department of Endocrinology, Diabetes and Metabolism, Kitasato University School of Medicine, Sagamihara, Japan.
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Zhang J, Zheng Y, Martens L, Pfeiffer AFH. The Regulation and Secretion of Glucagon in Response to Nutrient Composition: Unraveling Their Intricate Mechanisms. Nutrients 2023; 15:3913. [PMID: 37764697 PMCID: PMC10536047 DOI: 10.3390/nu15183913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/31/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
Glucagon was initially regarded as a hyperglycemic substance; however, recent research has revealed its broader role in metabolism, encompassing effects on glucose, amino acids (AAs), and lipid metabolism. Notably, the interplay of glucagon with nutrient intake, particularly of AAs, and non-nutrient components is central to its secretion. Fasting and postprandial hyperglucagonemia have long been linked to the development and progression of type 2 diabetes (T2DM). However, recent studies have brought to light the positive impact of glucagon agonists on lipid metabolism and energy homeostasis. This review explores the multifaceted actions of glucagon, focusing on its regulation, signaling pathways, and effects on glucose, AAs, and lipid metabolism. The interplay between glucagon and other hormones, including insulin and incretins, is examined to provide a mechanistic understanding of its functions. Notably, the liver-α-cell axis, which involves glucagon and amino acids, emerges as a critical aspect of metabolic regulation. The dysregulation of glucagon secretion and its impact on conditions such as T2DM are discussed. The review highlights the potential therapeutic applications of targeting the glucagon pathway in the treatment of metabolic disorders.
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Affiliation(s)
- Jiudan Zhang
- The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China;
- Department of Endocrinology, Diabetes and Nutrition, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10117 Berlin, Germany; (L.M.); (A.F.H.P.)
| | - Yang Zheng
- The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, China;
| | - Lisa Martens
- Department of Endocrinology, Diabetes and Nutrition, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10117 Berlin, Germany; (L.M.); (A.F.H.P.)
- Nutritional Science, University of Potsdam, 14469 Potsdam, Germany
| | - Andreas F. H. Pfeiffer
- Department of Endocrinology, Diabetes and Nutrition, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10117 Berlin, Germany; (L.M.); (A.F.H.P.)
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Lafferty R, Tanday N, Dubey V, Coulter-Parkhill A, Vishal K, Moffett RC, O'Harte F, Flatt PR, Irwin N. The glucagon receptor antagonist desHis 1Pro 4Glu 9-glucagon(Lys 12PAL) alters alpha-cell turnover and lineage in mice, but does not cause alpha-cell hyperplasia. Mol Cell Endocrinol 2023; 570:111932. [PMID: 37080378 DOI: 10.1016/j.mce.2023.111932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 02/24/2023] [Accepted: 04/16/2023] [Indexed: 04/22/2023]
Abstract
OBJECTIVE Glucagon receptor (GCGR) antagonism elicits antihyperglycemic effects in rodents and humans. The present study investigates whether the well characterised peptide-based GCGR antagonist, desHis1Pro4Glu9-glucagon (Lys12PAL), alters alpha-cell turnover or identity in mice. METHODS Multiple low-dose streptozotocin (STZ) treated (50 mg/kg bw, 5 days) transgenic GluCreERT2;ROSA26-eYFP mice were employed. STZ mice received twice daily administration of saline vehicle or desHis1Pro4Glu9-glucagon (Lys12PAL), at low- or high-dose (25 and 100 nmol/kg, respectively) for 11 days. RESULTS No GCGR antagonist induced changes in food or fluid intake, body weight or glucose homeostasis were observed. As expected, STZ dramatically reduced (P < 0.001) islet numbers and increased (P < 0.01) alpha-to beta-cell ratio, which was linked to elevated (P < 0.05) levels of beta-cell apoptosis. Whilst treatment with desHis1Pro4Glu9-glucagon (Lys12PAL) decreased (P < 0.05-P < 0.001) alpha- and beta-cell areas, it also helped restore the classic rodent islet alpha-cell mantle in STZ mice. Interestingly, low-dose desHis1Pro4Glu9-glucagon (Lys12PAL) increased (P < 0.05) alpha-cell apoptosis rates whilst high dose decreased (p < 0.05) this parameter. This difference reflects substantially increased (P < 0.001) alpha-to beta-cell transdifferentiation following high dose desHis1Pro4Glu9-glucagon (Lys12PAL) treatment, which was not fully manifest with low-dose therapy. CONCLUSIONS Taken together, the present study indicates that peptidic GCGR antagonists can positively influence alpha-cell turnover and lineage in identity in multiple low-dose STZ mice, but that such effects are dose-related.
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Affiliation(s)
- Ryan Lafferty
- Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Neil Tanday
- Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Vaibhav Dubey
- Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | | | - Karthick Vishal
- Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | | | - Finbarr O'Harte
- Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Peter R Flatt
- Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Nigel Irwin
- Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK.
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Pesta D, Jordan J. Macronutrient composition and metabolic regulation: Do our islets care what we eat? Acta Physiol (Oxf) 2022; 236:e13895. [PMID: 36214612 DOI: 10.1111/apha.13895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 10/04/2022] [Indexed: 01/29/2023]
Affiliation(s)
- Dominik Pesta
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.,Centre for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany.,Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany.,German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Germany.,Medical Faculty, University of Cologne, Cologne, Germany
| | - Jens Jordan
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
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Mingrone G, Castagneto-Gissey L, Bornstein SR. New Horizons: Emerging Antidiabetic Medications. J Clin Endocrinol Metab 2022; 107:e4333-e4340. [PMID: 36106900 DOI: 10.1210/clinem/dgac499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Indexed: 02/13/2023]
Abstract
Over the past century, since the discovery of insulin, the therapeutic offer for diabetes has grown exponentially, in particular for type 2 diabetes (T2D). However, the drugs in the diabetes pipeline are even more promising because of their impressive antihyperglycemic effects coupled with remarkable weight loss. An ideal medication for T2D should target not only hyperglycemia but also insulin resistance and obesity. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and the new class of GLP1 and gastric inhibitory polypeptide dual RAs counteract 2 of these metabolic defects of T2D, hyperglycemia and obesity, with stunning results that are similar to the effects of metabolic surgery. An important role of antidiabetic medications is to reduce the risk and improve the outcome of cardiovascular diseases, including coronary artery disease and heart failure with reduced or preserved ejection fraction, as well as diabetic nephropathy, as shown by SGLT2 inhibitors. This review summarizes the main drugs currently under development for the treatment of type 1 diabetes and T2D, highlighting their strengths and side effects.
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Affiliation(s)
- Geltrude Mingrone
- Department of Translational Medicine and Surgery, Università Cattolica del Sacro Cuore, Rome 00169, Italy
- Department of Medical and Surgical Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome 00169, Italy
- Division of Diabetes & Nutritional Sciences, School of Cardiovascular and Metabolic Medicine & Sciences, Faculty of Life Sciences & Medicine, King's College London, London WC2R 2LS, UK
| | | | - Stefan R Bornstein
- Division of Diabetes & Nutritional Sciences, School of Cardiovascular and Metabolic Medicine & Sciences, Faculty of Life Sciences & Medicine, King's College London, London WC2R 2LS, UK
- Department of Medicine III, Universitätsklinikum Carl Gustav Carus an der Technischen Universität Dresden, Dresden 01307, Germany
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Lafferty RA, McShane LM, Franklin ZJ, Flatt PR, O’Harte FPM, Irwin N. Sustained glucagon receptor antagonism in insulin-deficient high-fat-fed mice. J Endocrinol 2022; 255:91-101. [PMID: 36005280 PMCID: PMC9513641 DOI: 10.1530/joe-22-0106] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 08/24/2022] [Indexed: 11/17/2022]
Abstract
Discerning modification to the amino acid sequence of native glucagon can generate specific glucagon receptor (GCGR) antagonists, that include desHis1Pro4Glu9-glucagon and the acylated form desHis1Pro4Glu9(Lys12PAL)-glucagon. In the current study, we have evaluated the metabolic benefits of once-daily injection of these peptide-based GCGR antagonists for 18 days in insulin-resistant high-fat-fed (HFF) mice with streptozotocin (STZ)-induced insulin deficiency, namely HFF-STZ mice. Administration of desHis1Pro4Glu9-glucagon moderately (P < 0.05) decreased STZ-induced elevations of food intake. Body weight was not different between groups of HFF-STZ mice and both treatment interventions delayed (P < 0.05) the onset of hyperglycaemia. The treatments reduced (P < 0.05-P < 0.001) circulating and pancreatic glucagon, whilst desHis1Pro4Glu9(Lys12PAL)-glucagon also substantially increased (P < 0.001) pancreatic insulin stores. Oral glucose tolerance was appreciably improved (P < 0.05) by both antagonists, despite the lack of augmentation of glucose-stimulated insulin release. Interestingly, positive effects on i.p. glucose tolerance were less obvious suggesting important beneficial effects on gut function. Metabolic benefits were accompanied by decreased (P < 0.05-P < 0.01) locomotor activity and increases (P < 0.001) in energy expenditure and respiratory exchange ratio in both treatment groups. In addition, desHis1Pro4Glu9-glucagon increased (P < 0.01-P < 0.001) O2 consumption and CO2 production. Together, these data provide further evidence that peptidic GCGR antagonists are effective treatment options for obesity-driven forms of diabetes, even when accompanied by insulin deficiency.
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Affiliation(s)
- Ryan A Lafferty
- Biomedical Sciences Research Institute, Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Laura M McShane
- Biomedical Sciences Research Institute, Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Zara J Franklin
- Biomedical Sciences Research Institute, Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Peter R Flatt
- Biomedical Sciences Research Institute, Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Finbarr P M O’Harte
- Biomedical Sciences Research Institute, Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
| | - Nigel Irwin
- Biomedical Sciences Research Institute, Centre for Diabetes, Ulster University, Coleraine, Northern Ireland, UK
- Correspondence should be addressed to N Irwin:
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Vasileva A, Marx T, Beaudry JL, Stern JH. Glucagon receptor signaling at white adipose tissue does not regulate lipolysis. Am J Physiol Endocrinol Metab 2022; 323:E389-E401. [PMID: 36002172 PMCID: PMC9576180 DOI: 10.1152/ajpendo.00078.2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Although the physiological role of glucagon receptor signaling in the liver is well defined, the impact of glucagon receptor (Gcgr) signaling on white adipose tissue (WAT) continues to be debated. Although numerous studies propose that glucagon stimulates WAT lipolysis, we lack evidence that physiological concentrations of glucagon regulate WAT lipolysis. In turn, we performed studies in both wild-type and WAT Gcgr knockout mice to determine if glucagon regulates lipolysis at WAT in the mouse. We assessed the effects of fasting and acute exogenous glucagon administration in wild-type C57BL/6J and GcgrAdipocyte+/+ versus GcgrAdipocyte-/- mice. Using an ex vivo lipolysis protocol, we further examined the direct effects of glucagon on physiologically (fasted) and pharmacologically stimulated lipolysis. We found that adipocyte Gcgr expression did not affect fasting-induced lipolysis or hepatic lipid accumulation in lean or diet-induced obese (DIO) mice. Acute glucagon administration did not affect serum nonesterified fatty acids (NEFA), leptin, or adiponectin concentration, but did increase serum glucose and FGF21, regardless of genotype. Glucagon did not affect ex vivo lipolysis in explants from either GcgrAdipocyte+/+ or GcgrAdipocyte-/- mice. Gcgr expression did not affect fasting-induced or isoproterenol-stimulated lipolysis from WAT explants. Moreover, glucagon receptor signaling at WAT did not affect body weight or glucose homeostasis in lean or DIO mice. Our studies have established that physiological levels of glucagon do not regulate WAT lipolysis, either directly or indirectly. Given that glucagon receptor agonism can improve dyslipidemia and decrease hepatic lipid accumulation, it is critical to understand the tissue-specific effects of glucagon receptor action. Unlike the crucial role of hepatic glucagon receptor signaling in maintaining glucose and lipid homeostasis, we observed no metabolic consequence of WAT glucagon receptor deletion.NEW & NOTEWORTHY It has been postulated that glucagon stimulates lipolysis and fatty acid release from white adipose tissue. We observed no metabolic effects of eliminating or activating glucagon receptor signaling at white adipose tissue.
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Affiliation(s)
- Anastasiia Vasileva
- Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona
| | - Tyler Marx
- Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona
| | - Jacqueline L Beaudry
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Jennifer H Stern
- Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona
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Hædersdal S, Lund A, Nielsen-Hannerup E, Maagensen H, Forman JL, Holst JJ, Knop FK, Vilsbøll T. The glucagon receptor antagonist LY2409021 does not affect gastrointestinal-mediated glucose disposal or the incretin effect in individuals with and without type 2 diabetes. Eur J Endocrinol 2022; 187:507-518. [PMID: 35977072 DOI: 10.1530/eje-22-0291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 08/17/2022] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Gastrointestinal-mediated glucose disposal (GIGD) during oral glucose tolerance test (OGTT) reflects the percentage of glucose disposal caused by mechanisms elicited by the oral route of glucose administration. GIGD is reduced in patients with type 2 diabetes (T2D) due to a reduced incretin effect and possibly also due to inappropriate suppression of glucagon after oral glucose. We investigated the effect of glucagon receptor antagonism on GIGD, the incretin effect and glucose excursions in patients with T2D and controls without diabetes. DESIGN A double-blind, randomised, placebo-controlled crossover study was conducted. METHODS Ten patients with T2D and 10 gender-, age- and BMI-matched controls underwent two 50 g OGTTs and 2 isoglycaemic i.v. glucose infusions, succeeding (~10 h) single-dose administration of 100 mg of the glucagon receptor antagonist LY2409021 or placebo, respectively. RESULTS Compared to placebo, LY2409021 reduced fasting plasma glucose in patients with T2D and controls. Plasma glucose excursions after oral glucose assessed by baseline-subtracted area under the curve were increased by LY2409021 compared to placebo in both groups, but no effect of LY2409021 on GIGD or the incretin effect was observed. LY2409021 increased fasting glucagon concentrations three-fold compared to placebo concentrations. CONCLUSIONS Glucagon receptor antagonism with LY2409021 had no effect on the impaired GIGD or the impaired incretin effect in patients with T2D and did also not affect these parameters in the controls. Surprisingly, we observed reduced oral glucose tolerance with LY2409021 which may be specific for this glucagon receptor antagonist.
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Affiliation(s)
- Sofie Hædersdal
- Clinical Research, Copenhagen University Hospital - Steno Diabetes Center Copenhagen, Herlev, Denmark
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, Hellerup, Denmark
- Danish Diabetes Academy, Odense University Hospital, Odense, Denmark
| | - Asger Lund
- Clinical Research, Copenhagen University Hospital - Steno Diabetes Center Copenhagen, Herlev, Denmark
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, Hellerup, Denmark
| | - Elisabeth Nielsen-Hannerup
- Clinical Research, Copenhagen University Hospital - Steno Diabetes Center Copenhagen, Herlev, Denmark
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, Hellerup, Denmark
| | - Henrik Maagensen
- Clinical Research, Copenhagen University Hospital - Steno Diabetes Center Copenhagen, Herlev, Denmark
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, Hellerup, Denmark
| | - Julie L Forman
- Department of Public Health, Section of Biostatistics, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Novo Nordisk Foundation 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
| | - Filip K Knop
- Clinical Research, Copenhagen University Hospital - Steno Diabetes Center Copenhagen, Herlev, Denmark
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, Hellerup, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tina Vilsbøll
- Clinical Research, Copenhagen University Hospital - Steno Diabetes Center Copenhagen, Herlev, Denmark
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, Hellerup, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Franklin ZJ, Lafferty RA, Flatt PR, McShane LM, O'Harte FP, Irwin N. Metabolic effects of combined glucagon receptor antagonism and glucagon-like peptide-1 receptor agonism in high fat fed mice. Biochimie 2022; 199:60-67. [DOI: 10.1016/j.biochi.2022.04.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 04/05/2022] [Accepted: 04/13/2022] [Indexed: 01/19/2023]
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12
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Spezani R, Mandarim-de-Lacerda CA. The current significance and prospects for the use of dual receptor agonism GLP-1/Glucagon. Life Sci 2022; 288:120188. [PMID: 34861287 DOI: 10.1016/j.lfs.2021.120188] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 11/17/2021] [Accepted: 11/25/2021] [Indexed: 12/20/2022]
Abstract
The therapeutic arsenal for treating type 2 diabetes mellitus (T2DM) has been enriched recently with the inclusion of type 1 glucagon-like peptide (GLP-1). GLP-1 receptor agonists (RA) secondarily reduce appetite, decrease gastric emptying, and reduce body weight. This effect has been used to treat overweight/obesity, especially with comorbidities associated with T2DM. However, the first formulations and adverse effects gradually gave way to new formulations with fewer unpleasant effects and a more extended period of action (weekly subcutaneous administration and even oral administration), which improved the acceptance and adherence to the treatment. Therefore, titration of GLP-1RA should be done gradually. Furthermore, when side effects are consistent and intolerable after weeks/months of titration, a lower dose or a combination of antidiabetic therapies should be implemented, avoiding treatment interruption. The effort to produce increasingly powerful molecules with fewer side effects is the driving force behind the pharmaceutical industry. The unimolecular dual agonism GLP-1RA plus glucagon receptor agonism (GRA) represents an updated pharmacological indication for controlling blood glucose levels in treating T2DM and its comorbidities, showing better effects with less adverse impact than mono GLP-1RA. There are currently different proposals in this way by different laboratories. Nevertheless, the experimental results are promising and show that soon, we will have the contribution of new drugs for the treatment of T2DM.
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Affiliation(s)
- Renata Spezani
- Laboratory of Morphometry, Metabolism and Cardiovascular Diseases, Biomedical Center, Institute of Biology, The University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Carlos Alberto Mandarim-de-Lacerda
- Laboratory of Morphometry, Metabolism and Cardiovascular Diseases, Biomedical Center, Institute of Biology, The University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.
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13
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van der Velden WJC, Lindquist P, Madsen JS, Stassen RHMJ, Wewer Albrechtsen NJ, Holst JJ, Hauser AS, Rosenkilde MM. Molecular and in vivo phenotyping of missense variants of the human glucagon receptor. J Biol Chem 2021; 298:101413. [PMID: 34801547 PMCID: PMC8829087 DOI: 10.1016/j.jbc.2021.101413] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 11/04/2021] [Accepted: 11/11/2021] [Indexed: 01/09/2023] Open
Abstract
Naturally occurring missense variants of G protein–coupled receptors with loss of function have been linked to metabolic disease in case studies and in animal experiments. The glucagon receptor, one such G protein–coupled receptor, is involved in maintaining blood glucose and amino acid homeostasis; however, loss-of-function mutations of this receptor have not been systematically characterized. Here, we observed fewer glucagon receptor missense variants than expected, as well as lower allele diversity and fewer variants with trait associations as compared with other class B1 receptors. We performed molecular pharmacological phenotyping of 38 missense variants located in the receptor extracellular domain, at the glucagon interface, or with previously suggested clinical implications. These variants were characterized in terms of cAMP accumulation to assess glucagon-induced Gαs coupling, and of recruitment of β-arrestin-1/2. Fifteen variants were impaired in at least one of these downstream functions, with six variants affected in both cAMP accumulation and β-arrestin-1/2 recruitment. For the eight variants with decreased Gαs signaling (D63ECDN, P86ECDS, V96ECDE, G125ECDC, R2253.30H, R3085.40W, V3686.59M, and R3787.35C) binding experiments revealed preserved glucagon affinity, although with significantly reduced binding capacity. Finally, using the UK Biobank, we found that variants with wildtype-like Gαs signaling did not associate with metabolic phenotypes, whereas carriers of cAMP accumulation-impairing variants displayed a tendency toward increased risk of obesity and increased body mass and blood pressure. These observations are in line with the essential role of the glucagon system in metabolism and support that Gαs is the main signaling pathway effecting the physiological roles of the glucagon receptor.
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Affiliation(s)
- Wijnand J C van der Velden
- Laboratory for Molecular Pharmacology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Peter Lindquist
- Laboratory for Molecular Pharmacology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jakob S Madsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Roderick H M J Stassen
- Laboratory for Molecular Pharmacology, 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; Novo Nordisk Foundation Center for Protein 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; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences University of Copenhagen, Copenhagen, Denmark
| | - Alexander S Hauser
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Mette M Rosenkilde
- Laboratory for Molecular Pharmacology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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14
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Wewer Albrechtsen NJ. The glucose-mobilizing effect of glucagon at fasting is mediated by cyclic AMP. Am J Physiol Endocrinol Metab 2021; 321:E571-E574. [PMID: 34369821 DOI: 10.1152/ajpendo.00172.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Nicolai J Wewer Albrechtsen
- Department of Clinical Biochemistry, Rigshospitalet & Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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15
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Pickford P, Lucey M, Rujan RM, McGlone ER, Bitsi S, Ashford FB, Corrêa IR, Hodson DJ, Tomas A, Deganutti G, Reynolds CA, Owen BM, Tan TM, Minnion J, Jones B, Bloom SR. Partial agonism improves the anti-hyperglycaemic efficacy of an oxyntomodulin-derived GLP-1R/GCGR co-agonist. Mol Metab 2021; 51:101242. [PMID: 33933675 PMCID: PMC8163982 DOI: 10.1016/j.molmet.2021.101242] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/19/2021] [Accepted: 04/22/2021] [Indexed: 02/08/2023] Open
Abstract
OBJECTIVE Glucagon-like peptide-1 and glucagon receptor (GLP-1R/GCGR) co-agonism can maximise weight loss and improve glycaemic control in type 2 diabetes and obesity. In this study, we investigated the cellular and metabolic effects of modulating the balance between G protein and β-arrestin-2 recruitment at GLP-1R and GCGR using oxyntomodulin (OXM)-derived co-agonists. This strategy has been previously shown to improve the duration of action of GLP-1R mono-agonists by reducing target desensitisation and downregulation. METHODS Dipeptidyl dipeptidase-4 (DPP-4)-resistant OXM analogues were generated and assessed for a variety of cellular readouts. Molecular dynamic simulations were used to gain insights into the molecular interactions involved. In vivo studies were performed in mice to identify the effects on glucose homeostasis and weight loss. RESULTS Ligand-specific reductions in β-arrestin-2 recruitment were associated with slower GLP-1R internalisation and prolonged glucose-lowering action in vivo. The putative benefits of GCGR agonism were retained, with equivalent weight loss compared to the GLP-1R mono-agonist liraglutide despite a lesser degree of food intake suppression. The compounds tested showed only a minor degree of biased agonism between G protein and β-arrestin-2 recruitment at both receptors and were best classified as partial agonists for the two pathways measured. CONCLUSIONS Diminishing β-arrestin-2 recruitment may be an effective way to increase the therapeutic efficacy of GLP-1R/GCGR co-agonists. These benefits can be achieved by partial rather than biased agonism.
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Affiliation(s)
- Phil Pickford
- Section of Endocrinology and Investigative Medicine, Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, W12 0NN, UK
| | - Maria Lucey
- Section of Endocrinology and Investigative Medicine, Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, W12 0NN, UK
| | - Roxana-Maria Rujan
- Centre for Sport, Exercise, and Life Sciences, Faculty of Health and Life Sciences, Coventry University, Alison Gingell Building, CV1 5FB, UK
| | - Emma Rose McGlone
- Section of Endocrinology and Investigative Medicine, Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, W12 0NN, UK
| | - Stavroula Bitsi
- Section of Cell Biology and Functional Genomics, Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, W12 0NN, UK
| | - Fiona B Ashford
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK; Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, Birmingham, UK
| | | | - David J Hodson
- Institute of Metabolism and Systems Research (IMSR) and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK; Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, Birmingham, UK
| | - Alejandra Tomas
- Section of Cell Biology and Functional Genomics, Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, W12 0NN, UK
| | - Giuseppe Deganutti
- Centre for Sport, Exercise, and Life Sciences, Faculty of Health and Life Sciences, Coventry University, Alison Gingell Building, CV1 5FB, UK
| | - Christopher A Reynolds
- Centre for Sport, Exercise, and Life Sciences, Faculty of Health and Life Sciences, Coventry University, Alison Gingell Building, CV1 5FB, UK; School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Bryn M Owen
- Section of Endocrinology and Investigative Medicine, Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, W12 0NN, UK
| | - Tricia M Tan
- Section of Endocrinology and Investigative Medicine, Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, W12 0NN, UK
| | - James Minnion
- Section of Endocrinology and Investigative Medicine, Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, W12 0NN, UK
| | - Ben Jones
- Section of Endocrinology and Investigative Medicine, Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, W12 0NN, UK.
| | - Stephen R Bloom
- Section of Endocrinology and Investigative Medicine, Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, W12 0NN, UK
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16
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Nauck MA, Wefers J, Meier JJ. Treatment of type 2 diabetes: challenges, hopes, and anticipated successes. Lancet Diabetes Endocrinol 2021; 9:525-544. [PMID: 34181914 DOI: 10.1016/s2213-8587(21)00113-3] [Citation(s) in RCA: 114] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/06/2021] [Accepted: 04/07/2021] [Indexed: 12/12/2022]
Abstract
Despite the successful development of new therapies for the treatment of type 2 diabetes, such as glucagon-like peptide-1 (GLP-1) receptor agonists and sodium-glucose cotransporter-2 inhibitors, the search for novel treatment options that can provide better glycaemic control and at reduce complications is a continuous effort. The present Review aims to present an overview of novel targets and mechanisms and focuses on glucose-lowering effects guiding this search and developments. We discuss not only novel developments of insulin therapy (eg, so-called smart insulin preparation with a glucose-dependent mode of action), but also a group of drug classes for which extensive research efforts have not been rewarded with obvious clinical impact. We discuss the potential clinical use of the salutary adipokine adiponectin and the hepatokine fibroblast growth factor (FGF) 21, among others. A GLP-1 peptide receptor agonist (semaglutide) is now available for oral absorption, and small molecules activating GLP-1 receptors appear on the horizon. Bariatric surgery and its accompanying changes in the gut hormonal milieu offer a background for unimolecular peptides interacting with two or more receptors (for GLP-1, glucose-dependent insulinotropic polypeptide, glucagon, and peptide YY) and provide more substantial glycaemic control and bodyweight reduction compared with selective GLP-1 receptor agonists. These and additional approaches will help expand the toolbox of effective medications needed for optimising the treatment of well delineated subgroups of type 2 diabetes or help develop personalised approaches for glucose-lowering drugs based on individual characteristics of our patients.
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Affiliation(s)
- Michael A Nauck
- Diabetes Division, Katholisches Klinikum Bochum, St Josef Hospital, Ruhr University Bochum, Bochum, Germany.
| | - Jakob Wefers
- Diabetes Division, Katholisches Klinikum Bochum, St Josef Hospital, Ruhr University Bochum, Bochum, Germany
| | - Juris J Meier
- Diabetes Division, Katholisches Klinikum Bochum, St Josef Hospital, Ruhr University Bochum, Bochum, Germany
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17
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Mechanism of insulin resistance in obesity: a role of ATP. Front Med 2021; 15:372-382. [PMID: 34047935 DOI: 10.1007/s11684-021-0862-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 04/25/2021] [Indexed: 12/12/2022]
Abstract
Obesity increases the risk of type 2 diabetes through the induction of insulin resistance. The mechanism of insulin resistance has been extensively investigated for more than 60 years, but the essential pathogenic signal remains missing. Existing hypotheses include inflammation, mitochondrial dysfunction, hyperinsulinemia, hyperglucagonemia, glucotoxicity, and lipotoxicity. Drug discoveries based on these hypotheses are unsuccessful in the development of new medicines. In this review, multidisciplinary literature is integrated to evaluate ATP as a primary signal for insulin resistance. The ATP production is elevated in insulin-sensitive cells under obese conditions independent of energy demand, which we have named "mitochondrial overheating." Overheating occurs because of substrate oversupply to mitochondria, leading to extra ATP production. The ATP overproduction contributes to the systemic insulin resistance through several mechanisms, such as inhibition of AMPK, induction of mTOR, hyperinsulinemia, hyperglucagonemia, and mitochondrial dysfunction. Insulin resistance represents a feedback regulation of energy oversupply in cells to control mitochondrial overloading by substrates. Insulin resistance cuts down the substrate uptake to attenuate mitochondrial overloading. The downregulation of the mitochondrial overloading by medicines, bypass surgeries, calorie restriction, and physical exercise leads to insulin sensitization in patients. Therefore, ATP may represent the primary signal of insulin resistance in the cellular protective response to the substrate oversupply. The prevention of ATP overproduction represents a key strategy for insulin sensitization.
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18
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Lafferty RA, O’Harte FPM, Irwin N, Gault VA, Flatt PR. Proglucagon-Derived Peptides as Therapeutics. Front Endocrinol (Lausanne) 2021; 12:689678. [PMID: 34093449 PMCID: PMC8171296 DOI: 10.3389/fendo.2021.689678] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 05/05/2021] [Indexed: 12/12/2022] Open
Abstract
Initially discovered as an impurity in insulin preparations, our understanding of the hyperglycaemic hormone glucagon has evolved markedly over subsequent decades. With description of the precursor proglucagon, we now appreciate that glucagon was just the first proglucagon-derived peptide (PGDP) to be characterised. Other bioactive members of the PGDP family include glucagon-like peptides -1 and -2 (GLP-1 and GLP-2), oxyntomodulin (OXM), glicentin and glicentin-related pancreatic peptide (GRPP), with these being produced via tissue-specific processing of proglucagon by the prohormone convertase (PC) enzymes, PC1/3 and PC2. PGDP peptides exert unique physiological effects that influence metabolism and energy regulation, which has witnessed several of them exploited in the form of long-acting, enzymatically resistant analogues for treatment of various pathologies. As such, intramuscular glucagon is well established in rescue of hypoglycaemia, while GLP-2 analogues are indicated in the management of short bowel syndrome. Furthermore, since approval of the first GLP-1 mimetic for the management of Type 2 diabetes mellitus (T2DM) in 2005, GLP-1 therapeutics have become a mainstay of T2DM management due to multifaceted and sustainable improvements in glycaemia, appetite control and weight loss. More recently, longer-acting PGDP therapeutics have been developed, while newfound benefits on cardioprotection, bone health, renal and liver function and cognition have been uncovered. In the present article, we discuss the physiology of PGDP peptides and their therapeutic applications, with a focus on successful design of analogues including dual and triple PGDP receptor agonists currently in clinical development.
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Affiliation(s)
| | | | | | - Victor A. Gault
- School of Biomedical Sciences, Ulster University, Coleraine, United Kingdom
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19
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Yang B, Gelfanov VM, Perez-Tilve D, DuBois B, Rohlfs R, Levy J, Douros JD, Finan B, Mayer JP, DiMarchi RD. Optimization of Truncated Glucagon Peptides to Achieve Selective, High Potency, Full Antagonists. J Med Chem 2021; 64:4697-4708. [PMID: 33821647 DOI: 10.1021/acs.jmedchem.0c02069] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Antagonism of glucagon's biological action is a proven strategy for decreasing glucose in diabetic animals and patients. To achieve full, potent, and selective suppression, we chemically optimized N-terminally truncated glucagon fragments for the identification and establishment of the minimum sequence peptide, [Glu9]glucagon(6-29) amide (11) as a full antagonist in cellular signaling and receptor binding (IC50 = 36 nM). Substitution of Phe6 with l-3-phenyllactic acid (Pla) produced [Pla6, Glu9]glucagon(6-29) amide (21), resulting in a 3-fold improvement in receptor binding (IC50 = 12 nM) and enhanced antagonist potency. Further substitution of Glu9 and Asn28 with aspartic acid yielded [Pla6, Asp28]glucagon amide (26), which demonstrated a further increase in inhibitory potency (IC50 = 9 nM), and improved aqueous solubility. Peptide 26 and a palmitoylated analogue, [Pla6, Lys10(γGluγGlu-C16), Asp28]glucagon(6-29) amide (31), displayed sustained duration in vivo action that successfully reversed glucagon-induced glucose elevation in mice.
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Affiliation(s)
- Bin Yang
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States.,Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - Vasily M Gelfanov
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States.,Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - Diego Perez-Tilve
- Department of Medicine, University of Cincinnati, Cincinnati, Ohio 45267, United States
| | - Barent DuBois
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - Rebecca Rohlfs
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - Jay Levy
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - Jonathan D Douros
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - Brian Finan
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - John P Mayer
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Richard D DiMarchi
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
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20
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Alexiadou K, Cuenco J, Howard J, Wewer Albrechtsen NJ, Ilesanmi I, Kamocka A, Tharakan G, Behary P, Bech PR, Ahmed AR, Purkayastha S, Wheller R, Fleuret M, Holst JJ, Bloom SR, Khoo B, Tan TMM. Proglucagon peptide secretion profiles in type 2 diabetes before and after bariatric surgery: 1-year prospective study. BMJ Open Diabetes Res Care 2020; 8:8/1/e001076. [PMID: 32209584 PMCID: PMC7103850 DOI: 10.1136/bmjdrc-2019-001076] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Revised: 01/20/2020] [Accepted: 02/07/2020] [Indexed: 12/18/2022] Open
Abstract
INTRODUCTION Hyperglucagonemia is a key pathophysiological driver of type 2 diabetes. Although Roux-en-Y gastric bypass (RYGB) is a highly effective treatment for diabetes, it is presently unclear how surgery alters glucagon physiology. The aim of this study was to characterize the behavior of proglucagon-derived peptide (glucagon, glucagon-like peptide-1 (GLP-1), oxyntomodulin, glicentin) secretion after RYGB surgery. RESEARCH DESIGN AND METHODS Prospective study of 19 patients with obesity and pre-diabetes/diabetes undergoing RYGB. We assessed the glucose, insulin, GLP-1, glucose-dependent insulinotropic peptide (GIP), oxyntomodulin, glicentin and glucagon responses to a mixed-meal test (MMT) before and 1, 3 and 12 months after surgery. Glucagon was measured using a Mercodia glucagon ELISA using the 'Alternative' improved specificity protocol, which was validated against a reference liquid chromatography combined with mass spectrometry method. RESULTS After RYGB, there were early improvements in fasting glucose and glucose tolerance and the insulin response to MMT was accelerated and amplified, in parallel to significant increases in postprandial GLP-1, oxyntomodulin and glicentin secretion. There was a significant decrease in fasting glucagon levels at the later time points of 3 and 12 months after surgery. Glucagon was secreted in response to the MMT preoperatively and postoperatively in all patients and there was no significant change in this postprandial secretion. There was no significant change in GIP secretion. CONCLUSIONS There is a clear difference in the dynamics of secretion of proglucagon peptides after RYGB. The reduction in fasting glucagon secretion may be one of the mechanisms driving later improvements in glycemia after RYGB. TRIAL REGISTRATION NUMBER NCT01945840.
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Affiliation(s)
- Kleopatra Alexiadou
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Joyceline Cuenco
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - James Howard
- Drug Development Solutions, LGC Bioscience, Fordham, Cambridgeshire, UK
| | - Nicolai Jacob Wewer Albrechtsen
- Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark
- NNF Center for Protein Research, University of Copenhagen Faculty of Health and Medical Sciences, Copenhagen, Denmark
| | - Ibiyemi Ilesanmi
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Anna Kamocka
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - George Tharakan
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Preeshila Behary
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Paul R Bech
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Ahmed R Ahmed
- Department of Surgery and Cancer, Imperial College London, London, UK
| | | | - Robert Wheller
- Drug Development Solutions, LGC Bioscience, Fordham, Cambridgeshire, UK
| | - Matthieu Fleuret
- Drug Development Solutions, LGC Bioscience, Fordham, Cambridgeshire, UK
| | - Jens Juul Holst
- Department of Biomedical Sciences and the NNF Center for Basic Metabolic Research, University of Copenhagen Panum Institute, Copenhagen, Denmark
| | - Stephen R Bloom
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Bernard Khoo
- Division of Medicine, University College London, London, UK
| | - Tricia M-M Tan
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
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21
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Gilon P. The Role of α-Cells in Islet Function and Glucose Homeostasis in Health and Type 2 Diabetes. J Mol Biol 2020; 432:1367-1394. [PMID: 31954131 DOI: 10.1016/j.jmb.2020.01.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 12/23/2019] [Accepted: 01/06/2020] [Indexed: 01/09/2023]
Abstract
Pancreatic α-cells are the major source of glucagon, a hormone that counteracts the hypoglycemic action of insulin and strongly contributes to the correction of acute hypoglycemia. The mechanisms by which glucose controls glucagon secretion are hotly debated, and it is still unclear to what extent this control results from a direct action of glucose on α-cells or is indirectly mediated by β- and/or δ-cells. Besides its hyperglycemic action, glucagon has many other effects, in particular on lipid and amino acid metabolism. Counterintuitively, glucagon seems also required for an optimal insulin secretion in response to glucose by acting on its cognate receptor and, even more importantly, on GLP-1 receptors. Patients with diabetes mellitus display two main alterations of glucagon secretion: a relative hyperglucagonemia that aggravates hyperglycemia, and an impaired glucagon response to hypoglycemia. Under metabolic stress states, such as diabetes, pancreatic α-cells also secrete GLP-1, a glucose-lowering hormone, whereas the gut can produce glucagon. The contribution of extrapancreatic glucagon to the abnormal glucose homeostasis is unclear. Here, I review the possible mechanisms of control of glucagon secretion and the role of α-cells on islet function in healthy state. I discuss the possible causes of the abnormal glucagonemia in diabetes, with particular emphasis on type 2 diabetes, and I briefly comment the current antidiabetic therapies affecting α-cells.
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Affiliation(s)
- Patrick Gilon
- Université Catholique de Louvain, Institute of Experimental and Clinical Research, Pole of Endocrinology, Diabetes and Nutrition, Avenue Hippocrate 55 (B1.55.06), Brussels, B-1200, Belgium.
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