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Lymperopoulos A, Borges JI, Stoicovy RA. Cyclic Adenosine Monophosphate in Cardiac and Sympathoadrenal GLP-1 Receptor Signaling: Focus on Anti-Inflammatory Effects. Pharmaceutics 2024; 16:693. [PMID: 38931817 PMCID: PMC11206770 DOI: 10.3390/pharmaceutics16060693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Revised: 05/18/2024] [Accepted: 05/21/2024] [Indexed: 06/28/2024] Open
Abstract
Glucagon-like peptide-1 (GLP-1) is a multifunctional incretin hormone with various physiological effects beyond its well-characterized effect of stimulating glucose-dependent insulin secretion in the pancreas. An emerging role for GLP-1 and its receptor, GLP-1R, in brain neuroprotection and in the suppression of inflammation, has been documented in recent years. GLP-1R is a G protein-coupled receptor (GPCR) that couples to Gs proteins that stimulate the production of the second messenger cyclic 3',5'-adenosine monophosphate (cAMP). cAMP, acting through its two main effectors, protein kinase A (PKA) and exchange protein directly activated by cAMP (Epac), exerts several anti-inflammatory (and some pro-inflammatory) effects in cells, depending on the cell type. The present review discusses the cAMP-dependent molecular signaling pathways elicited by the GLP-1R in cardiomyocytes, cardiac fibroblasts, central neurons, and even in adrenal chromaffin cells, with a particular focus on those that lead to anti-inflammatory effects by the GLP-1R. Fully elucidating the role cAMP plays in GLP-1R's anti-inflammatory properties can lead to new and more precise targets for drug development and/or provide the foundation for novel therapeutic combinations of the GLP-1R agonist medications currently on the market with other classes of drugs for additive anti-inflammatory effect.
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Affiliation(s)
- Anastasios Lymperopoulos
- Laboratory for the Study of Neurohormonal Control of the Circulation, Department of Pharmaceutical Sciences, Barry and Judy Silverman College of Pharmacy, Nova Southeastern University, Fort Lauderdale, FL 33328-2018, USA; (J.I.B.); (R.A.S.)
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2
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Tee SA, Tsatlidis V, Razvi S. The GLP-1 receptor agonist exenatide reduces serum TSH by its effect on body weight in people with type 2 diabetes. Clin Endocrinol (Oxf) 2023; 99:401-408. [PMID: 36843143 DOI: 10.1111/cen.14901] [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: 12/07/2022] [Revised: 02/22/2023] [Accepted: 02/24/2023] [Indexed: 02/28/2023]
Abstract
OBJECTIVE Glucagon-like peptide-1 receptor agonist (GLP-1 RA) therapy in patients with type 2 diabetes and obesity leads to a significant reduction in serum thyrotropin (TSH) levels but it is unclear whether this is related to weight loss and improvement in sensitivity to thyroid hormones (TH). DESIGN, PATIENTS AND MEASUREMENTS We prospectively analysed clinical and biochemical data in patients with type 2 diabetes and obesity who were commenced on the GLP-1 RA exenatide and followed them for 12 months. We assessed the relationship between changes in body weight and serum TSH and resistance to TH indices. RESULTS In 112 patients (mean age: 53.5 years, 43.8% female, mean body mass index: 39.8 kg/m2 ), 12 months of exenatide treatment was associated with a mean (95% CI) percent body weight loss of 6.5% (5.0%-8.1%) and change in serum TSH of -0.25 mU/L (-0.43 to -0.06). There was a significant negative and nonlinear relationship between change in serum TSH and percent body weight loss: -0.25 mU/L with 5%, -0.4 mU/L with 10% and -0.5 mU/L with 15%, respectively, whereas a rise in serum TSH of 0.5 mU/L was associated with 5% weight gain. There were no changes observed in serum FT4 levels with weight loss but a significant reduction in resistance to TH indices was noted. CONCLUSIONS Exenatide therapy reduces serum TSH levels and improves central sensitivity to TH action over 12 months via its effect on weight loss. The effectiveness of weight loss strategies, rather than TH replacement, should be investigated in individuals with obesity and mildly raised serum TSH levels.
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Affiliation(s)
- Su Ann Tee
- Department of Endocrinology, Gateshead Health NHS Foundation Trust, Gateshead, UK
| | - Vasileios Tsatlidis
- Department of Endocrinology, Gateshead Health NHS Foundation Trust, Gateshead, UK
| | - Salman Razvi
- Department of Endocrinology, Gateshead Health NHS Foundation Trust, Gateshead, UK
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
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3
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Chen L, Yun Y, Guo S, Wang X, Xiong M, Zhao T, Xu T, Shen J, Xie X, Wang K. Discovery of Novel 5,6-Dihydro-1,2,4-triazine Derivatives as Efficacious Glucagon-Like Peptide-1 Receptor Agonists. J Med Chem 2023. [PMID: 37286364 DOI: 10.1021/acs.jmedchem.3c00320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Danuglipron is the most representative small-molecule agonist of the glucagon-like peptide-1 receptor (GLP-1R) and has received considerable attention due to positive results in the treatment of type 2 diabetes mellitus (T2DM) and obesity in clinical trials. However, hERG inhibition, lower activity than endogenous GLP-1, and a short action time represent limitations in terms of feasible application. In this study, we report a new class of 5,6-dihydro-1,2,4-triazine derivatives that serve to eliminate potential hERG inhibition caused by the piperidine ring of danuglipron. Applying systematic in vitro to in vivo screening, we have identified compound 42 as a highly potent and selective GLP-1R agonist, which delivers improved (7-fold) efficacy in stimulating cAMP accumulation compared with danuglipron and which exhibits acceptable drug-like properties. Furthermore, 42 significantly reduces glucose excursion and inhibits food intake of hGLP-1R Knock-In mice. These effects are longer-lasting than that shown by danuglipron, demonstrating feasibility in the treatment of T2DM and obesity.
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Affiliation(s)
- Lili Chen
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Ying Yun
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
| | - Shimeng Guo
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Xiaoyan Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Muya Xiong
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Tingting Zhao
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210046, China
| | - Tifei Xu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jianhua Shen
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Xin Xie
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Kai Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
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4
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Glucagon-like Peptide-1 Receptor Agonists in the Management of Type 2 Diabetes Mellitus and Obesity: The Impact of Pharmacological Properties and Genetic Factors. Int J Mol Sci 2022; 23:ijms23073451. [PMID: 35408810 PMCID: PMC8998939 DOI: 10.3390/ijms23073451] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/19/2022] [Accepted: 03/21/2022] [Indexed: 02/06/2023] Open
Abstract
Glucagon-like peptide-1 (GLP-1) receptor agonists are a new class of antihyperglycemic drugs that enhance appropriate pancreatic β-cell secretion, pancreatic α-cell (glucagon) suppression, decrease liver glucose production, increase satiety through their action on the central nervous system, slow gastric emptying time, and increase insulin action on peripheral tissue. They are effective in the management of type 2 diabetes mellitus and have a favorable effect on weight loss. Their cardiovascular and renal safety has been extensively investigated and confirmed in many clinical trials. Recently, evidence has shown that in addition to the existing approaches for the treatment of obesity, semaglutide in higher doses promotes weight loss and can be used as a drug to treat obesity. However, some T2DM and obese patients do not achieve a desired therapeutic effect of GLP-1 receptor agonists. This could be due to the multifactorial etiologies of T2DM and obesity, but genetic variability in the GLP-1 receptor or signaling pathways also needs to be considered in non-responders to GLP-1 receptor agonists. This review focuses on the pharmacological, clinical, and genetic factors that may influence the response to GLP-1 receptor agonists in the treatment of type 2 diabetes mellitus and obesity.
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5
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Cong Z, Chen LN, Ma H, Zhou Q, Zou X, Ye C, Dai A, Liu Q, Huang W, Sun X, Wang X, Xu P, Zhao L, Xia T, Zhong W, Yang D, Eric Xu H, Zhang Y, Wang MW. Molecular insights into ago-allosteric modulation of the human glucagon-like peptide-1 receptor. Nat Commun 2021; 12:3763. [PMID: 34145245 PMCID: PMC8213797 DOI: 10.1038/s41467-021-24058-z] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 05/28/2021] [Indexed: 01/04/2023] Open
Abstract
The glucagon-like peptide-1 (GLP-1) receptor is a validated drug target for metabolic disorders. Ago-allosteric modulators are capable of acting both as agonists on their own and as efficacy enhancers of orthosteric ligands. However, the molecular details of ago-allosterism remain elusive. Here, we report three cryo-electron microscopy structures of GLP-1R bound to (i) compound 2 (an ago-allosteric modulator); (ii) compound 2 and GLP-1; and (iii) compound 2 and LY3502970 (a small molecule agonist), all in complex with heterotrimeric Gs. The structures reveal that compound 2 is covalently bonded to C347 at the cytoplasmic end of TM6 and triggers its outward movement in cooperation with the ECD whose N terminus penetrates into the GLP-1 binding site. This allows compound 2 to execute positive allosteric modulation through enhancement of both agonist binding and G protein coupling. Our findings offer insights into the structural basis of ago-allosterism at GLP-1R and may aid the design of better therapeutics. The glucagon-like peptide-1 (GLP-1) receptor is a key regulator of glucose homeostasis and a drug target for type 2 diabetes but available GLP-1R agonists are suboptimal due to several side-effects. Here authors report the cryo-EM structure of GLP-1R bound to an ago-allosteric modulator in complex with heterotrimeric Gs which offers insights into the molecular details of ago-allosterism.
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Affiliation(s)
- Zhaotong Cong
- School of Pharmacy, Fudan University, Shanghai, China.,The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Li-Nan Chen
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Honglei Ma
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Qingtong Zhou
- School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Xinyu Zou
- School of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Chenyu Ye
- School of Pharmacy, Fudan University, Shanghai, China.,The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Antao Dai
- The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Qing Liu
- The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Wei Huang
- Qilu Regor Therapeutics, Inc., Shanghai, China
| | | | - Xi Wang
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Peiyu Xu
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Lihua Zhao
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Tian Xia
- School of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Wenge Zhong
- Qilu Regor Therapeutics, Inc., Shanghai, China
| | - Dehua Yang
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. .,The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. .,University of Chinese Academy of Sciences, Beijing, China.
| | - H Eric Xu
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. .,University of Chinese Academy of Sciences, Beijing, China.
| | - Yan Zhang
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China. .,MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Medicine, Hangzhou, China. .,Key Laboratory of Immunity and Inflammatory Diseases of Zhejiang Province, Hangzhou, China. .,Zhejiang Laboratory for Systems and Precision Medicine, Zhejiang University Medical Center, Hangzhou, China. .,School of Life Science and Technology, ShanghaiTech University, Shanghai, China.
| | - Ming-Wei Wang
- School of Pharmacy, Fudan University, Shanghai, China. .,The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. .,School of Basic Medical Sciences, Fudan University, Shanghai, China. .,The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. .,University of Chinese Academy of Sciences, Beijing, China. .,School of Life Science and Technology, ShanghaiTech University, Shanghai, China.
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Wang X, Ma B, Chen J, You H, Sheng C, Yang P, Qu S. Glucagon-like Peptide-1 Improves Fatty Liver and Enhances Thermogenesis in Brown Adipose Tissue via Inhibiting BMP4-Related Signaling Pathway in High-Fat-Diet-Induced Obese Mice. Int J Endocrinol 2021; 2021:6620289. [PMID: 33986800 PMCID: PMC8093078 DOI: 10.1155/2021/6620289] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 02/03/2021] [Accepted: 04/04/2021] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE Glucagon-like peptide-1 (GLP-1) receptor agonist is effective in decreasing blood glucose and body weight. It could improve fatty liver with unclear mechanisms. Hence, we aimed to explore whether GLP-1 could improve fatty liver by regulating the BMP4-related signaling pathway. METHODS Fifteen C57BL/6 mice were randomly assigned to 3 groups. Group A and Group B were fed with a high-fat diet (HFD) to induce fatty liver while Group C was fed with a regular diet (RD) for 24 weeks. Group A and Group B received a subcutaneous injection of exenatide and vehicle (0.9% NaCl), respectively, once daily at doses of 10 nmol/kg during the last 8 weeks. Bodyweight, liver weight, and lipid levels were measured. Histological analyses of liver tissue were performed. The expression of protein and gene measured by western blotting and real-time polymerase chain reaction (RT-PCR) was compared. RESULTS Eight-week exenatide treatment significantly decreased body weight in Group A (from 44.08 ± 2.89 g to 39.22 ± 1.88 g, P = 0.045). Group A had lower body weight and liver weight than Group B at 24 weeks (39.22 ± 1.88 g vs. 47.34 ± 2.43 g, P = 0.001 and 1.70 ± 0.20 g vs. 2.48 ± 0.19 g, P = 0.001, respectively). Moreover, Group A showed significantly less liver steatosis than Group B. Additionally, Group A led to slightly decreased serum triglyceride (TG) and cholesterol (TC) levels compared to Group B. Western blotting showed that exenatide could prevent HFD-induced upregulation of BMP4 levels and downstream activation of Smad1/5/8 and the P38 MAPK signaling pathway in the liver. Furthermore, exenatide treatment could reduce BMP4 and enhance UCP-1 (an important thermogenin) in brown adipose tissue (BAT). CONCLUSION Exenatide could improve HFD-induced hepatic steatosis and enhance thermogenesis in BAT, which may be partly attributed to the inhibition of the BMP4-related signaling pathway.
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Affiliation(s)
- Xingchun Wang
- Thyriod Research Center of Shanghai, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
- Department of Endocrinology and Metabolism, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
| | - Bingwei Ma
- Department of Endocrinology and Metabolism, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
- Department of Gastrointestinal Surgery, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
| | - Jiaqi Chen
- Suzhou Municipal Hospital, Suzhou 215000, Jiangsu, China
| | - Hui You
- Department of Endocrinology and Metabolism, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
| | - Chunjun Sheng
- Thyriod Research Center of Shanghai, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
- Department of Endocrinology and Metabolism, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
| | - Peng Yang
- Thyriod Research Center of Shanghai, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
- Department of Endocrinology and Metabolism, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
| | - Shen Qu
- Thyriod Research Center of Shanghai, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
- Department of Endocrinology and Metabolism, Shanghai Tenth People's Hospital of Tongji University, School of Medicine, Tongji University, Shanghai 200072, China
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7
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Kręcisz P, Czarnecka K, Królicki L, Mikiciuk-Olasik E, Szymański P. Radiolabeled Peptides and Antibodies in Medicine. Bioconjug Chem 2020; 32:25-42. [PMID: 33325685 PMCID: PMC7872318 DOI: 10.1021/acs.bioconjchem.0c00617] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
![]()
Radiolabeled peptides
are a relatively new, very specific radiotracer
group, which is still expanding. This group is very diverse in terms
of peptide size. It contains very small structures containing several
amino acids and whole antibodies. Moreover, radiolabeled peptides
are diverse in terms of the binding aim and therapeutic or diagnostic
applications. The majority of this class of radiotracers is utilized
in oncology, where the same structure can be used in therapy and diagnostic
imaging by varying the radionuclide. In this study, we collected new
reports of radiolabeled peptide applications in diagnosis and therapy
in oncology and other fields of medicine. Radiolabeled peptides are
also increasingly being used in rheumatology, cardiac imaging, or
neurology. The studies collected in this review concern new therapeutic
and diagnostic procedures in humans and new structures tested on animals.
We also performed an analysis of clinical trials, which concerns application
of radiolabeled peptides and antibodies that were reported in the
clinicaltrials.gov database between 2008 and 2018.
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Affiliation(s)
- Paweł Kręcisz
- Department of Pharmaceutical Chemistry, Drug Analyses and Radiopharmacy, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Lodz, Poland
| | - Kamila Czarnecka
- Department of Pharmaceutical Chemistry, Drug Analyses and Radiopharmacy, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Lodz, Poland
| | - Leszek Królicki
- Department of Nuclear Medicine, Medical University of Warsaw, ul. Banacha 1 a, 02-097, Warsaw, Poland
| | - Elżbieta Mikiciuk-Olasik
- Department of Pharmaceutical Chemistry, Drug Analyses and Radiopharmacy, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Lodz, Poland
| | - Paweł Szymański
- Department of Pharmaceutical Chemistry, Drug Analyses and Radiopharmacy, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Lodz, Poland
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A synthetic method to assay adhesion-family G-protein coupled receptors. Determination of the G-protein coupling profile of ADGRG6(GPR126). Biochem Biophys Res Commun 2020; 534:317-322. [PMID: 33248691 DOI: 10.1016/j.bbrc.2020.11.086] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 11/18/2020] [Indexed: 12/19/2022]
Abstract
G-protein coupled receptors (GPCRs) are the largest family of membrane-spanning receptors in metazoans and mediate diverse biological processes such as chemotaxis, vision, and neurotransmission. Adhesion GPCRs represent an understudied class of GPCRs. Adhesion GPCRs (ADGRs) are activated by an intrinsic proteolytic mechanism executed by the G-protein autoproteolysis inducing domain that defines this class of GPCRs. It is hypothesized that agonist ligands modulate the proteolyzed receptor to regulate the activity of a tethered agonist peptide that is an intramolecular activator of ADGRs. The mechanism of activation of ADGRs in physiological settings is unclear and the toolbox for interrogating ADGR physiology in cellular models is limited. Therefore, we generated a novel enterokinase-activated tethered ligand system for ADGRG6(GPR126). Enterokinase addition to cells expressing a synthetic ADGRG6 protein induced potent and efficacious signal transduction through heterotrimeric G-protein coupled second messenger pathways including cyclic nucleotide production, intracellular calcium mobilization, and GPCR-pathway linked reporter gene induction. These studies support the hypothesis that ADGRG6(GPR126) is coupled to multiple heterotrimeric G-proteins: including Gαs, Gαq, and Gα12. This novel assay method is robust, specific, and compatible with numerous cell pharmacology approaches. We present a new tool for determination of the biological function of ADGRs and the identification of ligands that engage these receptors.
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Song L, Barrett DG, Cox KL, Efanov AM, Syed SK, Tomandl D, Willard FS. A High-Throughput Assay for the Pancreatic Islet Beta-Cell Potassium Channel: Use in the Pharmacological Characterization of Insulin Secretagogues Identified from Phenotypic Screening. Assay Drug Dev Technol 2020; 19:27-37. [PMID: 33164547 DOI: 10.1089/adt.2020.1011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Phenotypic screening is a neoclassical approach for drug discovery. We conducted phenotypic screening for insulin secretion enhancing agents using INS-1E insulinoma cells as a model system for pancreatic beta-cells. A principal regulator of insulin secretion in beta-cells is the metabolically regulated potassium channel Kir6.2/SUR1 complex. To characterize hit compounds, we developed an assay to quantify endogenous potassium channel activity in INS-1E cells. We quantified ligand-regulated potassium channel activity in INS-1E cells using fluorescence imaging and thallium flux. Potassium channel activity was metabolically regulated and coupled to insulin secretion. The pharmacology of channel opening agents (diazoxide) and closing agents (sulfonylureas) was used to validate the applicability of the assay. A precise high-throughput assay was enabled, and phenotypic screening hits were triaged to enable a higher likelihood of discovering chemical matter with novel and useful mechanisms of action.
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Affiliation(s)
- Luyan Song
- Quantitative Biology, Lilly Research Laboratories, Indianapolis, Indiana, USA
| | - David G Barrett
- Discovery Chemistry, Lilly Research Laboratories, Indianapolis, Indiana, USA
| | - Karen L Cox
- Quantitative Biology, Lilly Research Laboratories, Indianapolis, Indiana, USA
| | - Alexander M Efanov
- Diabetes and Complications Therapeutic Area, Lilly Research Laboratories, Indianapolis, Indiana, USA
| | - Samreen K Syed
- Diabetes and Complications Therapeutic Area, Lilly Research Laboratories, Indianapolis, Indiana, USA
| | - Dirk Tomandl
- Discovery Informatics, Lilly Research Laboratories, Indianapolis, Indiana, USA
| | - Francis S Willard
- Quantitative Biology, Lilly Research Laboratories, Indianapolis, Indiana, USA
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10
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Liu Q, Cai BY, Zhu LX, Xin X, Wang X, An ZM, Li S, Hu YY, Feng Q. Liraglutide modulates gut microbiome and attenuates nonalcoholic fatty liver in db/db mice. Life Sci 2020; 261:118457. [PMID: 32961235 DOI: 10.1016/j.lfs.2020.118457] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/06/2020] [Accepted: 09/15/2020] [Indexed: 02/07/2023]
Abstract
AIMS Liraglutide, a glucagon-like peptide-1(GLP-1) analog, is effective for the treatment of type II diabetes and nonalcoholic fatty liver disease (NAFLD). It was proved that gut microbiome plays a role in the development of NAFLD. This study aims to observe the therapeutic effect of liraglutide on nonalcoholic fatty liver (NAFL) in mice and effect on the gut microbial community. MAIN METHODS The db/db mice were used as the NAFL model, and lactulose was used as the positive control drug. Hepatic triglyceride, liver histopathology, and indices of glucolipid metabolism, including fasting blood glucose, fasting insulin, insulin resistance index and blood lipids were evaluated after treatment of liraglutide or lactulose for four weeks. The colonic microbiome of the mice was analyzed by 16S rRNA gene sequencing. KEY FINDINGS Liraglutide significantly reduced the hepatic triglyceride (TG) content, alanine aminotransferase (ALT) activity, fasting blood glucose, insulin resistance and serum low density lipoprotein (LDL) in the db/db mice. In terms of hepatic pathologies, hepatic steatosis was significantly improved after liraglutide treating. Microbiome analysis revealed that liraglutide significantly increased the abundance of Akkermansia, Romboutsia, norank_f_Bacteroidales_S24-7_group, and decreased the abundance of Klebsiella, Anaerotruncus, Bacteroides, Lachnospiraceae_UCG-001, Lachnospiraceae_NK4A136_group, Ruminiclostridium, uncultured_f__Ruminococcaceae, and Desulfovibrio. SIGNIFICANCE The results of the present study suggested that liraglutide had a certain therapeutic effect on fatty liver in db/db mice and had an impact on the composition of the intestinal microflora, especially some bacteria related to glucolipid metabolism and intestinal inflammation. Affecting gut microbiome might be a potential mechanism of liraglutide in treating NAFL.
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Affiliation(s)
- Qian Liu
- Shuguang Hospital Affliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203,China; Baoshan District Hospital of Integrated Traditional Chinese Medicine of Shanghai, Shanghai 201900, China
| | - Bei-Yu Cai
- Shuguang Hospital Affliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203,China
| | - Li-Xin Zhu
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan 510655, China
| | - Xin Xin
- Shuguang Hospital Affliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203,China
| | - Xin Wang
- Shuguang Hospital Affliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203,China
| | - Zi-Ming An
- Shuguang Hospital Affliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203,China
| | - Shuang Li
- Baoshan District Hospital of Integrated Traditional Chinese Medicine of Shanghai, Shanghai 201900, China.
| | - Yi-Yang Hu
- Shuguang Hospital Affliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203,China.
| | - Qin Feng
- Shuguang Hospital Affliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203,China.
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11
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Willard FS, Meredith TD, Showalter AD, Ma W, Ho JD, Sauder JM, Sloop KW. Synthetic protease-activated class B GPCRs. Biochem Biophys Res Commun 2020; 530:246-251. [DOI: 10.1016/j.bbrc.2020.07.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 07/06/2020] [Indexed: 11/28/2022]
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12
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Saad ZA, Khodeer DM, Zaitone SA, Ahmed AAM, Moustafa YM. Exenatide ameliorates experimental non-alcoholic fatty liver in rats via suppression of toll-like receptor 4/NFκB signaling: Comparison to metformin. Life Sci 2020; 253:117725. [PMID: 32348835 DOI: 10.1016/j.lfs.2020.117725] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 02/07/2023]
Abstract
AIMS Non-alcoholic fatty liver disease (NAFLD) is a common liver disease. This study aimed to evaluate the role of exenatide compared with metformin in halting the progression of fatty liver stimulated by a high-fat diet (HiFD) in rats. MAIN METHODS Thirty male Wistar rats were allocated into 6 groups, 5 rats per each group. Group I: maintained on normal diet (normal group) for fourteen weeks. The other five groups were kept on HiFD throughout the experiment, HiFD was administered beside pharmacological treatments/or vehicle. Group II: (NAFLD control group), group III: received metformin (60 mg/kg/day, P.O.), group IV-VI: received exenatide (10, 20, and 40 μg/kg/day, S.C.) respectively for 7 weeks. At the end of the therapeutic period, fasting blood glucose was determined, and body weight was registered. Rats were sacrificed, and blood samples were taken to measure serum insulin, lipids, and liver enzymes. The liver index and homeostasis model of insulin resistance (HOMA-IR) index were calculated. Further, livers were dissected for histopathological examination and Western blot analysis. KEY FINDINGS NAFLD control group showed hyperglycemia, hyperinsulinemia, increased liver enzymes, hypertriglyceridemia, elevated hepatic lipid peroxides, and inflammatory mediators (interlukin 6, nuclear factor-κB, tumor necrosis factor-α and Toll-like receptor4) in addition to hepatic fatty degeneration. In a dose-dependent manner, exenatide significantly improved most of the above mentioned markers in comparsion with NAFLD at P≤0.05. SIGNIFICANCE The current results suggest that exenatide is equivalent to metformin in controlling insulin resistance, body weight gain, improving liver function, suppressing inflammation, and attenuating NAFLD progression in male rats.
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Affiliation(s)
- Zeinab A Saad
- Medical Administration, Suez Canal University, Ismailia, Egypt
| | - Dina M Khodeer
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt.
| | - Sawsan A Zaitone
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt; Department of Pharmacology and Toxicology, Faculty of Pharmacy, University of Tabuk, Tabuk, Saudi Arabia
| | - Amal A M Ahmed
- Department of Histology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, Egypt
| | - Yasser M Moustafa
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt
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13
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Willard FS, Ho JD, Sloop KW. Discovery and pharmacology of the covalent GLP-1 receptor (GLP-1R) allosteric modulator BETP: A novel tool to probe GLP-1R pharmacology. ADVANCES IN PHARMACOLOGY 2020; 88:173-191. [PMID: 32416867 DOI: 10.1016/bs.apha.2020.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The glucagon-like peptide-1 receptor (GLP-1R) is a significant therapeutic target for small molecule drug discovery given the therapeutic impact of peptide agonists in the diabetes sphere. We review the discovery and subsequent characterization of the small molecule GLP-1R allosteric modulator 4-(3-(Benzyloxy)phenyl)-2-(ethylsulfinyl)-6-(trifluoromethyl)pyrimidine (BETP). BETP is a covalent modulator of the GLP-1R, and we discuss the pharmacological implications and possible structural basis of this novel mode of action. We highlight the insights into class B G-protein coupled receptor pharmacology and biology provided by studies conducted with BETP. These include the descriptions of exquisite allosteric modulator probe dependence and biased signaling in vitro and in vivo. We conclude with an analysis of the utility of BETP as a chemical probe for the GLP-1R.
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Affiliation(s)
- Francis S Willard
- Quantitative Biology, Lilly Research Laboratories, Indianapolis, IN, United States.
| | - Joseph D Ho
- Lilly Biotechnology Center, San Diego, CA, United States
| | - Kyle W Sloop
- Diabetes and Complications, Lilly Research Laboratories, Indianapolis, IN, United States
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14
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Sencar ME, Sakiz D, Calapkulu M, Hepsen S, Kizilgul M, Ozturk IU, Ucan B, Bayram M, Cagir BB, Akin S, Ozbek M, Cakal E. The Effect of Exenatide on Thyroid-Stimulating Hormone and Thyroid Volume. Eur Thyroid J 2019; 8:307-311. [PMID: 31934556 PMCID: PMC6944867 DOI: 10.1159/000501895] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 06/19/2019] [Indexed: 01/03/2023] Open
Abstract
OBJECTIVE Glucagon-like peptide-1 (GLP-1) analogues are now widely used for the treatment of type 2 diabetes mellitus (DM). Many binding sites for GLP-1 have been demonstrated in the specific tissue compartments of organs in-cluding the brain and thyroid. The aim of this study was to investigate the effect of exenatide treatment on thyroid-stimulating hormone (TSH) and thyroid volume in diabetic patients without thyroid disease. MATERIAL AND METHODS The study included 46 diabetic patients without thyroid disease who were receiving exenatide treatment. Comparisons were made of total thyroid volume and serum concentrations of TSH at baseline and after 6 months of follow-up. RESULTS Of the 46 patients, 13 were excluded from the study, as they were unable to complete the treatment or left the follow-up process. After 6 months of exenatide treatment, the serum TSH concentration decreased significantly (from 2.3 [0.7-5.4] to 1.8 mIU/L [0.3-4.2], p= 0.007). There were no significant differences in thyroid volume (11.6 ± 9.0 vs. 12.1 ± 8.8 cm3, p = 0.19), free thyroxine (fT4), free tri-iodothyronine (fT3), and calcitonin levels before and after treatment. Thyroid volume was not affected by decreased TSH level (p:= 0.141) or a reduction in body mass index (BMI) (p > 0.05), and no correlation was detected between variation in TSH level and change in BMI (p > 0.05). CONCLUSIONS Exenatide treatment for 6 months significantly decreased serum TSH concentration but did not affect thyroid volume in diabetic patients without thyroid disease.
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Affiliation(s)
- Muhammed Erkam Sencar
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
- *Muhammed Erkam Sencar, MD, Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Sehit Omer Halisdemir Avenue, TR–06110 Ankara (Turkey), E-Mail
| | - Davut Sakiz
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Murat Calapkulu
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Sema Hepsen
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Muhammed Kizilgul
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Ilknur Unsal Ozturk
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Bekir Ucan
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Murat Bayram
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Busra Betul Cagir
- Department of Internal Medicine, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Safak Akin
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Mustafa Ozbek
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Erman Cakal
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
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15
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Qin K, Zhang S, Wang J, Liu D, Xiang Y, Ji X, Wei Y. Screening GLP-1 Receptor Ligands from Natural Products in Herbs through High-Content Technique. Comb Chem High Throughput Screen 2019; 22:445-454. [PMID: 31538889 DOI: 10.2174/1386207322666190919143735] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 05/15/2019] [Accepted: 08/26/2019] [Indexed: 11/22/2022]
Abstract
AIM AND OBJECTIVE Screening of active components from a natural product, especially from a crude extract, is a great challenge. To avoid potential activity interference of the N-terminus modification in the most common constructs based on GCPRs labeled with GFP technology, a Cterminus tGFP-labeled hGLP-1 receptor containing recombinant cell line hGLP-1R-tGFP was constructed and tried to be used in the screening of natural products from Chinese herb. MATERIALS AND METHODS The GLP1 receptor gene was amplified and the inserts pCMV6-AC-tGFP and tGFP were fused at the C-terminus of GLP1 receptor to construct a recombinant plasmid. The recombinant was transfected into U2OS cell and selected with antibiotics and flow cytometry. The constructed cell line was named as hGLP-1R-tGFP cell line. The expression levels of GLP-1R-tGFP protein were confirmed by western-blot. The fluorescence imaging of re-distribution from diffusing to aggregate spots inside the cells was quantitated and analyzed by High Content Screening (HCS) assay. Meanwhile, the specificity, stability and C-terminus function of hGLP-1R-tGFP cell line were characterized. In order to allow the recombinant cell line of hGLP-1R-tGFP to be suitable in highcontent system of Arrayscan-infinity-700 in screening mode, several conditions have also been optimized. In the end, a total of 100 crude extract samples provided by the Yunnan Institute of Materia Medica have been screened with this method. RESULTS Upon the activation of GLP-1 receptors by Exendin 4, fluorescent patches appeared on the cell membrane and subsequently internalized to form fluorescent aggregates inside the cells under fluorescent microscopy examination. The agonistic activity, sensitivity and specificity of the formation of fluorescent aggregate spot in hGLP-1R-tGFP cells have been confirmed by the activation of GLP-1R using the GLP-1analogues. The agonistic effects of GLP-1 analogues are blocked by a GLP-1R antagonist, Exendin9-39. The downstream of GLP-1 pathway, the activation of adenylate cyclase and the raising of cellular cAMP levels, remained intact in these tGFP modified C-terminus GLP-1 receptor cells. Meanwhile, a total of 100 crude extract samples from Chinese herbs have been screened by this method to find new active ingredients. CONCLUSION Combined with High Content Screening image and data automatic acquisition processing, a new screening assay based on a recombinant U2OS cell line which GFP labeled at the C terminus of GLP1 receptor has been developed. GLP-1R agonist activity in extracts of Astragalus propinquus and Panax notoginseng from Chinese herbs has been determined by this method.
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Affiliation(s)
- Kunhao Qin
- Faculty of Life Science and Biotechnology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Shengting Zhang
- Faculty of Life Science and Biotechnology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Jie Wang
- Faculty of Life Science and Biotechnology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Dongbo Liu
- State Key Laboratory of Subhealth Intervention Technology, Hunan Agricultural University, Changsha, Hunan, China
| | - Yingying Xiang
- Faculty of Life Science and Biotechnology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Xiuling Ji
- Faculty of Life Science and Biotechnology, Kunming University of Science and Technology, Kunming, Yunnan, China
| | - Yunlin Wei
- Faculty of Life Science and Biotechnology, Kunming University of Science and Technology, Kunming, Yunnan, China
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16
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Zhong X, Chen Z, Chen Q, Zhao W, Chen Z. Novel Site-Specific Fatty Chain-Modified GLP-1 Receptor Agonist with Potent Antidiabetic Effects. Molecules 2019; 24:molecules24040779. [PMID: 30795583 PMCID: PMC6412877 DOI: 10.3390/molecules24040779] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/15/2019] [Accepted: 02/15/2019] [Indexed: 11/30/2022] Open
Abstract
Glucagon-like peptide-1 receptor (GLP-1R) agonists have emerged as treatment options for type 2 diabetes mellitus (T2DM). Here, we designed a high-throughput GLP-1R extracellular domain (ECD)-based system that enabled the screening of high-potency receptor-biased GLP-1R agonists demonstrating new pharmacological virtues. Firstly, six 12-mer peptides (termed PEP01–06), screened from a large phage displayed peptide library were fused to the N-terminus of Exendin-4 (29–39) to generate PEP07–12. By the use of four lysine-altered PEP07 (PEP13–16) as the starting point, a series of fatty chain conjugates (PEP17–20) were synthesized and evaluated by in vitro GLP-1R-based cell assays. In addition, the acute and long-term in vivo effects on diet-induced obesity (DIO) mice were further evaluated. All four conjugates showed good receptor activation efficacy, and PEP20 was selected to undergo further assessment. Preclinical experiments in DIO mice demonstrated that PEP20 had significant insulinotropic activities and glucose-lowering abilities. Moreover, a prolonged antidiabetic effect of PEP20 was also observed by the hypoglycemic test in DIO mice. Furthermore, long-term treatment with PEP20 achieved beneficial effects on the food intake, weight gain, hemoglobin A1C (HbA1C) lowering activity, and glucose tolerance compared with the control and was similar to the Liraglutide. In conclusion, PEP20, a GLP-1R ECD-biased agonist, may provide a novel therapeutic approach to T2DM.
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Affiliation(s)
- Xia Zhong
- College of Life Science and Technology, Jinan University, Guangzhou 510000, China.
- Reyoung Biopharmaceuticals Co., Ltd, Suzhou 215000, China.
| | - Zhu Chen
- Reyoung Biopharmaceuticals Co., Ltd, Suzhou 215000, China.
- East China University of Science and Technology, Shanghai 200000, China.
| | - Qiong Chen
- Reyoung Biopharmaceuticals Co., Ltd, Suzhou 215000, China.
| | - Wei Zhao
- Reyoung Biopharmaceuticals Co., Ltd, Suzhou 215000, China.
| | - Zhi Chen
- East China University of Science and Technology, Shanghai 200000, China.
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17
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Lemos NE, Dieter C, Carlessi R, Rheinheimer J, Brondani LDA, Leitão CB, Bauer AC, Crispim D. Renal effects of exendin-4 in an animal model of brain death. Mol Biol Rep 2019; 46:2197-2207. [PMID: 30759298 DOI: 10.1007/s11033-019-04674-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/05/2019] [Indexed: 12/14/2022]
Abstract
Organ transplantation is the gold standard therapy for the majority of patients with terminal organ failure. However, it is still a limited treatment especially due to the low number of brain death (BD) donors in relation to the number of waiting list recipients. Strategies to increase the quantity and quality of donor organs have been studied, and the administration of exendin-4 (Ex-4) to the donor may be a promising approach. Male Wistar rats were randomized into 3 groups: (1) control, without central nervous system injury; (2) BD induced experimentally, and (3) BD induced experimentally + Ex-4 administered immediately after BD induction. After BD induction, animals were monitored for 6 h before blood collection and kidney biopsy. Kidney function was assessed by biochemical quantification of plasma kidney markers. Gene and protein expressions of inflammation- and stress-related genes were evaluated by RT-qPCR and immunoblot analysis. Animals treated with Ex-4 had lower creatinine and urea levels compared with controls. BD induced oxidative stress in kidney tissue through increased expression of Ucp2, Sod2 and Inos, and Ex-4 administration reduced the expression of these genes. Ex-4 also induced increased expression of the anti-apoptotic Bcl2 gene. Nlrp3 and Tnf expressions were up-regulated in the BD group compared with controls, but Ex-4 treatment had no effect on these genes. Our findings suggest that Ex-4 administration in BD rats reduces BD-induced kidney damage by decreasing the expression of oxidative stress genes and increasing the expression of Bcl2.
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Affiliation(s)
- Natália Emerim Lemos
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos 2350, prédio 12, 4° andar, Porto Alegre, Rio Grande Do Sul, 90035-003, Brazil.,Postgraduation Program in Medical Sciences: Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande Do Sul, Brazil
| | - Cristine Dieter
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos 2350, prédio 12, 4° andar, Porto Alegre, Rio Grande Do Sul, 90035-003, Brazil.,Postgraduation Program in Medical Sciences: Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande Do Sul, Brazil
| | - Rodrigo Carlessi
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Kent St., Bentley, Perth, WA, 6102, Australia
| | - Jakeline Rheinheimer
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos 2350, prédio 12, 4° andar, Porto Alegre, Rio Grande Do Sul, 90035-003, Brazil.,Postgraduation Program in Medical Sciences: Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande Do Sul, Brazil
| | - Letícia de Almeida Brondani
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos 2350, prédio 12, 4° andar, Porto Alegre, Rio Grande Do Sul, 90035-003, Brazil.,Postgraduation Program in Medical Sciences: Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande Do Sul, Brazil
| | - Cristiane Bauermann Leitão
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos 2350, prédio 12, 4° andar, Porto Alegre, Rio Grande Do Sul, 90035-003, Brazil.,Postgraduation Program in Medical Sciences: Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande Do Sul, Brazil
| | - Andrea Carla Bauer
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos 2350, prédio 12, 4° andar, Porto Alegre, Rio Grande Do Sul, 90035-003, Brazil.,Postgraduation Program in Medical Sciences: Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande Do Sul, Brazil.,Nephrology Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande Do Sul, Brazil
| | - Daisy Crispim
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos 2350, prédio 12, 4° andar, Porto Alegre, Rio Grande Do Sul, 90035-003, Brazil. .,Postgraduation Program in Medical Sciences: Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande Do Sul, Brazil.
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18
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Tapadia M, Carlessi R, Johnson S, Utikar R, Newsholme P. Lupin seed hydrolysate promotes G-protein-coupled receptor, intracellular Ca 2+ and enhanced glycolytic metabolism-mediated insulin secretion from BRIN-BD11 pancreatic beta cells. Mol Cell Endocrinol 2019; 480:83-96. [PMID: 30347229 DOI: 10.1016/j.mce.2018.10.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 10/18/2018] [Accepted: 10/19/2018] [Indexed: 12/14/2022]
Abstract
Lupin seed proteins have been reported to exhibit hypoglycaemic effects in animals and humans following oral administration, however little is known about its mechanism of action. This study investigated the signalling pathway(s) responsible for the insulinotropic effect of the hydrolysate obtained from lupin (Lupinus angustifolius L.) seed extracts utilizing BRIN-BD11 β-cells. The extract was treated with digestive enzymes to give a hydrolysate rich in biomolecules ≤7 kDa. Cells exhibited hydrolysate induced dose-dependent stimulation of insulin secretion and enhanced intracellular Ca2+ and glucose metabolism. The stimulatory effect of the hydrolysate was potentiated by depolarizing concentrations of KCl and was blocked by inhibitors of the ATP sensitive K+ channel, Gαq protein, phospholipase C (PLC) and protein kinase C (PKC). These findings reveal a novel mechanism for lupin hydrolysate stimulated insulin secretion via Gαq mediated signal transduction (Gαq/PLC/PKC) in the β-cells. Thus, lupin hydrolysates may have potential for nutraceutical treatment in type 2 diabetes.
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Affiliation(s)
- Mrunmai Tapadia
- Western Australia School of Mines (WASM): Minerals, Energy and Chemical Engineering, Curtin University, Perth, WA, 6102, Australia
| | - Rodrigo Carlessi
- School of Pharmacy and Biomedical Sciences, Curtin Health Innovation Research Institute Biosciences, Curtin University, Perth, WA, 6102, Australia.
| | - Stuart Johnson
- School of Molecular and Life Sciences, Curtin Health Innovation Research Institute, Curtin University, Perth, WA, 6845, Australia
| | - Ranjeet Utikar
- Western Australia School of Mines (WASM): Minerals, Energy and Chemical Engineering, Curtin University, Perth, WA, 6102, Australia
| | - Philip Newsholme
- School of Pharmacy and Biomedical Sciences, Curtin Health Innovation Research Institute Biosciences, Curtin University, Perth, WA, 6102, Australia.
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19
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Engineering of a GLP-1 analogue peptide/anti-PCSK9 antibody fusion for type 2 diabetes treatment. Sci Rep 2018; 8:17545. [PMID: 30510163 PMCID: PMC6277417 DOI: 10.1038/s41598-018-35869-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 11/08/2018] [Indexed: 12/13/2022] Open
Abstract
Type 2 diabetes (T2D) is a complex and progressive disease requiring polypharmacy to manage hyperglycaemia and cardiovascular risk factors. However, most patients do not achieve combined treatment goals. To address this therapeutic gap, we have developed MEDI4166, a novel glucagon-like peptide-1 (GLP-1) receptor agonist peptide fused to a proprotein convertase subtilisin/kexin type 9 (PCSK9) neutralising antibody that allows for glycaemic control and low-density lipoprotein cholesterol (LDL-C) lowering in a single molecule. The fusion has been engineered to deliver sustained peptide activity in vivo in combination with reduced potency, to manage GLP-1 driven adverse effects at high dose, and a favourable manufacturability profile. MEDI4166 showed robust and sustained LDL-C lowering in cynomolgus monkeys and exhibited the anticipated GLP-1 effects in T2D mouse models. We believe MEDI4166 is a novel molecule combining long acting agonist peptide and neutralising antibody activities to deliver a unique pharmacology profile for the management of T2D.
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20
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Li S, Wang X, Zhang J, Li J, Liu X, Ma Y, Han C, Zhang L, Zheng L. Exenatide ameliorates hepatic steatosis and attenuates fat mass and FTO gene expression through PI3K signaling pathway in nonalcoholic fatty liver disease. ACTA ACUST UNITED AC 2018; 51:e7299. [PMID: 29924135 PMCID: PMC6010322 DOI: 10.1590/1414-431x20187299] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 04/16/2018] [Indexed: 12/25/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a common disease associated with
metabolic syndrome and can lead to life-threatening complications like hepatic
carcinoma and cirrhosis. Exenatide, a glucagon-like peptide-1 (GLP-1) receptor
agonist antidiabetic drug, has the capacity to overcome insulin resistance and
attenuate hepatic steatosis but the specific underlying mechanism is unclear.
This study was designed to investigate the underlying molecular mechanisms of
exenatide therapy on NAFLD. We used in vivo and in
vitro techniques to investigate the protective effects of exenatide
on fatty liver via fat mass and obesity associated gene (FTO)
in a high-fat (HF) diet-induced NAFLD animal model and related cell culture
model. Exenatide significantly decreased body weight, serum glucose, insulin,
insulin resistance, serum free fatty acid, triglyceride, total cholesterol,
low-density lipoprotein, aspartate aminotransferase, and alanine
aminotransferase levels in HF-induced obese rabbits. Histological analysis
showed that exenatide significantly reversed HF-induced lipid accumulation and
inflammatory changes accompanied by decreased FTO mRNA and protein expression,
which were abrogated by PI3K inhibitor LY294002. This study indicated that
pharmacological interventions with GLP-1 may represent a promising therapeutic
strategy for NAFLD.
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Affiliation(s)
- Shan Li
- Department of Endocrinology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Xiaoman Wang
- Department of Endocrinology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Jielei Zhang
- Department of Endocrinology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Jingyi Li
- Department of Breast Surgery, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Xiaogang Liu
- Department of Endocrinology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Yuanyuan Ma
- Department of Endocrinology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Chao Han
- Department of Pharmacy, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Lixia Zhang
- Department of Endocrinology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Lili Zheng
- Department of Endocrinology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
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Lach G, Schellekens H, Dinan TG, Cryan JF. Anxiety, Depression, and the Microbiome: A Role for Gut Peptides. Neurotherapeutics 2018; 15:36-59. [PMID: 29134359 PMCID: PMC5794698 DOI: 10.1007/s13311-017-0585-0] [Citation(s) in RCA: 307] [Impact Index Per Article: 51.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The complex bidirectional communication between the gut and the brain is finely orchestrated by different systems, including the endocrine, immune, autonomic, and enteric nervous systems. Moreover, increasing evidence supports the role of the microbiome and microbiota-derived molecules in regulating such interactions; however, the mechanisms underpinning such effects are only beginning to be resolved. Microbiota-gut peptide interactions are poised to be of great significance in the regulation of gut-brain signaling. Given the emerging role of the gut-brain axis in a variety of brain disorders, such as anxiety and depression, it is important to understand the contribution of bidirectional interactions between peptide hormones released from the gut and intestinal bacteria in the context of this axis. Indeed, the gastrointestinal tract is the largest endocrine organ in mammals, secreting dozens of different signaling molecules, including peptides. Gut peptides in the systemic circulation can bind cognate receptors on immune cells and vagus nerve terminals thereby enabling indirect gut-brain communication. Gut peptide concentrations are not only modulated by enteric microbiota signals, but also vary according to the composition of the intestinal microbiota. In this review, we will discuss the gut microbiota as a regulator of anxiety and depression, and explore the role of gut-derived peptides as signaling molecules in microbiome-gut-brain communication. Here, we summarize the potential interactions of the microbiota with gut hormones and endocrine peptides, including neuropeptide Y, peptide YY, pancreatic polypeptide, cholecystokinin, glucagon-like peptide, corticotropin-releasing factor, oxytocin, and ghrelin in microbiome-to-brain signaling. Together, gut peptides are important regulators of microbiota-gut-brain signaling in health and stress-related psychiatric illnesses.
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Affiliation(s)
- Gilliard Lach
- APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Harriet Schellekens
- APC Microbiome Institute, University College Cork, Cork, Ireland
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
- Food for Health Ireland, University College Cork, Cork, Ireland
| | - Timothy G Dinan
- APC Microbiome Institute, University College Cork, Cork, Ireland
- Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland
| | - John F Cryan
- APC Microbiome Institute, University College Cork, Cork, Ireland.
- Food for Health Ireland, University College Cork, Cork, Ireland.
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Glucagon-like Peptide-1 (GLP-1) and neurotransmitters signaling in epilepsy: An insight review. Neuropharmacology 2017; 136:271-279. [PMID: 29129776 DOI: 10.1016/j.neuropharm.2017.11.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 11/07/2017] [Accepted: 11/08/2017] [Indexed: 12/16/2022]
Abstract
Epilepsy is one of the most prevalent neurological disorder affecting more than 50 million people worldwide. Numerous studies have suggested that an imbalance in glutamatergic (excitatory) and GABAergic (inhibitory) neurotransmitter system is one of the dominating pathophysiological mechanisms underlying the occurrence and progression of seizures. Further, this alteration in GABAergic and glutamatergic system disrupts the delicate balance of other neurotransmitters system in the brain. Emerging strides have documented the protective role of GLP-1 signaling on altered neurotransmitters signaling in Epilepsy and associated co-morbidities. GLP-1 is neuropeptide and synthesized by preproglucagon (PPG) neurons in the brain. GLP-1 receptors are widely distributed throughout the brain including hippocampus (CA3 and CA1 region) and implicated in various neurological disorders like Epilepsy. A complete understanding of alteration in neurotransmitters signaling will provide essential insight into the basic pathogenic mechanisms of epilepsy and may uncover novel targets for future drug therapies. Presently, treatment of epilepsy is palliative in nature, providing only symptomatic relief to patients. The apparent or traditional approach of treating epileptic subjects with anti-epileptic drugs is associated with variety of adverse effects. Therefore, alternative approaches that can restore altered neurotransmitter signaling are being tried and adopted. Present review is an attempt to highlight the emerging protective role of GLP-1 signaling on altered neurotransmitters signaling in epilepsy. Authors have made significant efforts to discuss effect of various GLP-1 analogs on various neurotransmitters system and associated molecular and cellular pathways as a potential drug target for the management of epilepsy and associated co-morbidities. This article is part of the Special Issue entitled 'Metabolic Impairment as Risk Factors for Neurodegenerative Disorders.'
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Lemos NE, Brondani LDA, Dieter C, Rheinheimer J, Bouças AP, Leitão CB, Crispim D, Bauer AC. Use of additives, scaffolds and extracellular matrix components for improvement of human pancreatic islet outcomes in vitro: A systematic review. Islets 2017; 9:73-86. [PMID: 28678625 PMCID: PMC5624286 DOI: 10.1080/19382014.2017.1335842] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 05/16/2017] [Accepted: 05/24/2017] [Indexed: 01/31/2023] Open
Abstract
Pancreatic islet transplantation is an established treatment to restore insulin independence in type 1 diabetic patients. Its success rates have increased lately based on improvements in immunosuppressive therapies and on islet isolation and culture. It is known that the quality and quantity of viable transplanted islets are crucial for the achievement of insulin independence and some studies have shown that a significant number of islets are lost during culture time. Thus, in an effort to improve islet yield during culture period, researchers have tested a variety of additives in culture media as well as alternative culture devices, such as scaffolds. However, due to the use of different categories of additives or devices, it is difficult to draw a conclusion on the benefits of these strategies. Therefore, the aim of this systematic review was to summarize the results of studies that described the use of medium additives, scaffolds or extracellular matrix (ECM) components during human pancreatic islets culture. PubMed and Embase repositories were searched. Of 5083 articles retrieved, a total of 37 articles fulfilled the eligibility criteria and were included in the review. After data extraction, articles were grouped as follows: 1) "antiapoptotic/anti-inflammatory/antioxidant," 2) "hormone," 3) "sulphonylureas," 4) "serum supplements," and 5) "scaffolds or ECM components." The effects of the reviewed additives, ECM or scaffolds on islet viability, apoptosis and function (glucose-stimulated insulin secretion - GSIS) were heterogeneous, making any major conclusion hard to sustain. Overall, some "antiapoptotic/anti-inflammatory/antioxidant" additives decreased apoptosis and improved GSIS. Moreover, islet culture with ECM components or scaffolds increased GSIS. More studies are needed to define the real impact of these strategies in improving islet transplantation outcomes.
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Affiliation(s)
- Natália Emerim Lemos
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduation Program in Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Letícia de Almeida Brondani
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduation Program in Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Cristine Dieter
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduation Program in Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Jakeline Rheinheimer
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduation Program in Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Ana Paula Bouças
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Cristiane Bauermann Leitão
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduation Program in Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Daisy Crispim
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduation Program in Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Andrea Carla Bauer
- Laboratory of Human Pancreatic Islet Biology, Endocrine Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduation Program in Endocrinology, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
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Silvestri AP, Cistrone PA, Dawson PE. Adapting the Glaser Reaction for Bioconjugation: Robust Access to Structurally Simple, Rigid Linkers. Angew Chem Int Ed Engl 2017; 56:10438-10442. [PMID: 28685936 PMCID: PMC5708120 DOI: 10.1002/anie.201705065] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Indexed: 12/26/2022]
Abstract
Copper-mediated coupling between alkynes to generate a structurally rigid, linear 1,3-diyne linkage has been known for over a century. However, the mechanistic requirement to simultaneously maintain CuI and an oxidant has limited its practical utility, especially for complex functional molecules in aqueous solution. We find that addition of a specific bpy-diol ligand protects unprotected peptides from CuII -mediated oxidative damage through the formation of an insoluble CuII gel which solves the critical challenge of applying Glaser coupling to substrates that are degraded by CuII . The generality of this method is illustrated through the conjugation of a series of polar and nonpolar labels onto a fully unprotected GLP-1R agonist through a linear 7 Å diynyl linker.
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Affiliation(s)
- Anthony P Silvestri
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Philip A Cistrone
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Philip E Dawson
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
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Cai Y, Liu Y, Culhane KJ, DeVree BT, Yang Y, Sunahara RK, Yan ECY. Purification of family B G protein-coupled receptors using nanodiscs: Application to human glucagon-like peptide-1 receptor. PLoS One 2017; 12:e0179568. [PMID: 28609478 PMCID: PMC5469476 DOI: 10.1371/journal.pone.0179568] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 05/31/2017] [Indexed: 12/16/2022] Open
Abstract
Family B G protein-coupled receptors (GPCRs) play vital roles in hormone-regulated homeostasis. They are drug targets for metabolic diseases, including type 2 diabetes and osteoporosis. Despite their importance, the signaling mechanisms for family B GPCRs at the molecular level remain largely unexplored due to the challenges in purification of functional receptors in sufficient amount for biophysical characterization. Here, we purified the family B GPCR human glucagon-like peptide-1 (GLP-1) receptor (GLP1R), whose agonists, e.g. exendin-4, are used for the treatment of type 2 diabetes mellitus. The receptor was expressed in HEK293S GnTl- cells using our recently developed protocol. The protocol incorporates the receptor into the native-like lipid environment of reconstituted high density lipoprotein (rHDL) particles, also known as nanodiscs, immediately after the membrane solubilization step followed by chromatographic purification, minimizing detergent contact with the target receptor to reduce denaturation and prolonging stabilization of receptor in lipid bilayers without extra steps of reconstitution. This method yielded purified GLP1R in nanodiscs that could bind to GLP-1 and exendin-4 and activate Gs protein. This nanodisc purification method can potentially be a general strategy to routinely obtain purified family B GPCRs in the 10s of microgram amounts useful for spectroscopic analysis of receptor functions and activation mechanisms.
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Affiliation(s)
- Yingying Cai
- Department of Chemistry, Yale University, New Haven, Connecticut, United States of America
| | - Yuting Liu
- Department of Chemistry, Yale University, New Haven, Connecticut, United States of America
| | - Kelly J. Culhane
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, United States of America
| | - Brian T. DeVree
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Yang Yang
- Nanobiology Institute, Yale University, New Haven, Connecticut, United States of America
- Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Roger K. Sunahara
- Department of Pharmacology, University of California at San Diego, La Jolla, California, United States of America
| | - Elsa C. Y. Yan
- Department of Chemistry, Yale University, New Haven, Connecticut, United States of America
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26
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Kodaganti BP, Mukunda P, Dakshinamurthy P, Manjunath Y, Shenoy BR, Kamanagowda V, Natarajan B, Maliwalave A, Unnikrishnan D, Murugesan S, Halan V, Ghosh M, Maity S. Microbial expression of Exendin-4 analog and its efficacy in mice model. Biologicals 2017; 48:82-91. [PMID: 28554726 DOI: 10.1016/j.biologicals.2017.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 05/09/2017] [Accepted: 05/16/2017] [Indexed: 02/06/2023] Open
Abstract
Exendin-4 is a GLP 1 agonist incretin-mimetic peptide hormone comprising 39 amino acids. Exenatide (Byetta®) is a chemically synthesized version of Exendin-4 with an additional C-terminal amidation. Exenatide acts as a GLP-1 receptor agonist. This paper illustrates the method adopted for cloning, fermentation and purification of recombinant Exendin-4 analog expressed in Escherichia coli. The biologically expressed analog was extensively characterized using different orthogonal methods to confirm their biological activity and physicochemical properties. It was observed that the expressed analog showed comparable functional properties as that of Byetta® irrespective of their modes of development. Further, in vivo efficacy of the recombinant Exendin-4 analog was studied in Oral Glucose Tolerance Test (OGTT) in mice models. Byetta® and Exendin-4 analog treated groups showed comparable glucose lowering activity in the OGTT model.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Sunit Maity
- Theramyt Novobiologics Pvt Ltd, Bangalore, India; Zumutor Biologics, Bangalore, India.
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27
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Hager MV, Johnson LM, Wootten D, Sexton PM, Gellman SH. β-Arrestin-Biased Agonists of the GLP-1 Receptor from β-Amino Acid Residue Incorporation into GLP-1 Analogues. J Am Chem Soc 2016; 138:14970-14979. [PMID: 27813409 PMCID: PMC5207657 DOI: 10.1021/jacs.6b08323] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Activation of a G protein-coupled receptor (GPCR) causes recruitment of multiple intracellular proteins, each of which can activate distinct signaling pathways. This complexity has engendered interest in agonists that preferentially stimulate subsets among the natural signaling pathways ("biased agonists"). We have examined analogues of glucagon-like peptide-1 (GLP-1) containing β-amino acid residues in place of native α residues at selected sites and found that some analogues differ from GLP-1 in terms of their relative abilities to promote G protein activation (as monitored via cAMP production) versus β-arrestin recruitment (as monitored via BRET assays). The α → β replacements generally cause modest declines in stimulation of cAMP production and β-arrestin recruitment, but for some replacement sets cAMP production is more strongly affected than is β-arrestin recruitment. The central portion of GLP-1 appears to be critical for achieving bias toward β-arrestin recruitment. These results suggest that backbone modification via α → β residue replacement may be a versatile source of agonists with biased GLP-1R activation profiles.
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Affiliation(s)
- Marlies V Hager
- Department of Chemistry, University of Wisconsin , Madison, Wisconsin 53706 United States
| | - Lisa M Johnson
- Department of Chemistry, University of Wisconsin , Madison, Wisconsin 53706 United States
| | - Denise Wootten
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University , Parkville, VIC 3052, Australia
| | - Patrick M Sexton
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University , Parkville, VIC 3052, Australia
| | - Samuel H Gellman
- Department of Chemistry, University of Wisconsin , Madison, Wisconsin 53706 United States
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28
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Pancreatic Beta Cell G-Protein Coupled Receptors and Second Messenger Interactions: A Systems Biology Computational Analysis. PLoS One 2016; 11:e0152869. [PMID: 27138453 PMCID: PMC4854486 DOI: 10.1371/journal.pone.0152869] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 03/21/2016] [Indexed: 12/17/2022] Open
Abstract
Insulin secretory in pancreatic beta-cells responses to nutrient stimuli and hormonal modulators include multiple messengers and signaling pathways with complex interdependencies. Here we present a computational model that incorporates recent data on glucose metabolism, plasma membrane potential, G-protein-coupled-receptors (GPCR), cytoplasmic and endoplasmic reticulum calcium dynamics, cAMP and phospholipase C pathways that regulate interactions between second messengers in pancreatic beta-cells. The values of key model parameters were inferred from published experimental data. The model gives a reasonable fit to important aspects of experimentally measured metabolic and second messenger concentrations and provides a framework for analyzing the role of metabolic, hormones and neurotransmitters changes on insulin secretion. Our analysis of the dynamic data provides support for the hypothesis that activation of Ca2+-dependent adenylyl cyclases play a critical role in modulating the effects of glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and catecholamines. The regulatory properties of adenylyl cyclase isoforms determine fluctuations in cytoplasmic cAMP concentration and reveal a synergistic action of glucose, GLP-1 and GIP on insulin secretion. On the other hand, the regulatory properties of phospholipase C isoforms determine the interaction of glucose, acetylcholine and free fatty acids (FFA) (that act through the FFA receptors) on insulin secretion. We found that a combination of GPCR agonists activating different messenger pathways can stimulate insulin secretion more effectively than a combination of GPCR agonists for a single pathway. This analysis also suggests that the activators of GLP-1, GIP and FFA receptors may have a relatively low risk of hypoglycemia in fasting conditions whereas an activator of muscarinic receptors can increase this risk. This computational analysis demonstrates that study of second messenger pathway interactions will improve understanding of critical regulatory sites, how different GPCRs interact and pharmacological targets for modulating insulin secretion in type 2 diabetes.
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Thompson A, Stephens JW, Bain SC, Kanamarlapudi V. Molecular Characterisation of Small Molecule Agonists Effect on the Human Glucagon Like Peptide-1 Receptor Internalisation. PLoS One 2016; 11:e0154229. [PMID: 27100083 PMCID: PMC4839733 DOI: 10.1371/journal.pone.0154229] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 04/11/2016] [Indexed: 01/23/2023] Open
Abstract
The glucagon-like peptide receptor (GLP-1R), which is a G-protein coupled receptor (GPCR), signals through both Gαs and Gαq coupled pathways and ERK phosphorylation to stimulate insulin secretion. The aim of this study was to determine molecular details of the effect of small molecule agonists, compounds 2 and B, on GLP-1R mediated cAMP production, intracellular Ca2+ accumulation, ERK phosphorylation and its internalisation. In human GLP-1R (hGLP-1R) expressing cells, compounds 2 and B induced cAMP production but caused no intracellular Ca2+ accumulation, ERK phosphorylation or hGLP-1R internalisation. GLP-1 antagonists Ex(9-39) and JANT-4 and the orthosteric binding site mutation (V36A) in hGLP-1R failed to inhibit compounds 2 and B induced cAMP production, confirming that their binding site distinct from the GLP-1 binding site on GLP-1R. However, K334A mutation of hGLP-1R, which affects Gαs coupling, inhibited GLP-1 as well as compounds 2 and B induced cAMP production, indicating that GLP-1, compounds 2 and B binding induce similar conformational changes in the GLP-1R for Gαs coupling. Additionally, compound 2 or B binding to the hGLP-1R had significantly reduced GLP-1 induced intracellular Ca2+ accumulation, ERK phosphorylation and hGLP-1R internalisation. This study illustrates pharmacology of differential activation of GLP-1R by GLP-1 and compounds 2 and B.
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Affiliation(s)
- Aiysha Thompson
- Institute of Life Science 1, Medical School, Swansea University, Singleton Park, Swansea, United Kingdom
| | - Jeffrey W. Stephens
- Institute of Life Science 1, Medical School, Swansea University, Singleton Park, Swansea, United Kingdom
| | - Stephen C. Bain
- Institute of Life Science 1, Medical School, Swansea University, Singleton Park, Swansea, United Kingdom
| | - Venkateswarlu Kanamarlapudi
- Institute of Life Science 1, Medical School, Swansea University, Singleton Park, Swansea, United Kingdom
- * E-mail:
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Zhang H, Sturchler E, Zhu J, Nieto A, Cistrone PA, Xie J, He L, Yea K, Jones T, Turn R, Di Stefano PS, Griffin PR, Dawson PE, McDonald PH, Lerner RA. Autocrine selection of a GLP-1R G-protein biased agonist with potent antidiabetic effects. Nat Commun 2015; 6:8918. [PMID: 26621478 PMCID: PMC4686834 DOI: 10.1038/ncomms9918] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 10/16/2015] [Indexed: 02/08/2023] Open
Abstract
Glucagon-like peptide-1 (GLP-1) receptor (GLP-1R) agonists have emerged as treatment options for type 2 diabetes mellitus (T2DM). GLP-1R signals through G-protein-dependent, and G-protein-independent pathways by engaging the scaffold protein β-arrestin; preferential signalling of ligands through one or the other of these branches is known as ‘ligand bias'. Here we report the discovery of the potent and selective GLP-1R G-protein-biased agonist, P5. We identified P5 in a high-throughput autocrine-based screening of large combinatorial peptide libraries, and show that P5 promotes G-protein signalling comparable to GLP-1 and Exendin-4, but exhibited a significantly reduced β-arrestin response. Preclinical studies using different mouse models of T2DM demonstrate that P5 is a weak insulin secretagogue. Nevertheless, chronic treatment of diabetic mice with P5 increased adipogenesis, reduced adipose tissue inflammation as well as hepatic steatosis and was more effective at correcting hyperglycaemia and lowering haemoglobin A1c levels than Exendin-4, suggesting that GLP-1R G-protein-biased agonists may provide a novel therapeutic approach to T2DM. GLP-1 is a gut hormone with glucose-lowering activity. Here the authors report the peptide, P5, a variant of the GLP-1 receptor agonist exendin-4, with 'biased' signalling activity, and show that P5 improves glucose homeostasis in diabetic mice by increasing adipose tissue hyperplasia.
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Affiliation(s)
- Hongkai Zhang
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Emmanuel Sturchler
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, Florida 33458, USA
| | - Jiang Zhu
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Ainhoa Nieto
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, Florida 33458, USA
| | - Philip A Cistrone
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Jia Xie
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - LinLing He
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Kyungmoo Yea
- Shanghai Institute for Advance Immunological Studies, Shanghai Tech University, Shanghai 200031, China
| | - Teresa Jones
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Rachel Turn
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, Florida 33458, USA
| | | | - Patrick R Griffin
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, Florida 33458, USA
| | - Philip E Dawson
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Patricia H McDonald
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, Florida 33458, USA
| | - Richard A Lerner
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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Cyclic alpha-conotoxin peptidomimetic chimeras as potent GLP-1R agonists. Eur J Med Chem 2015; 103:175-84. [DOI: 10.1016/j.ejmech.2015.08.046] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 08/18/2015] [Accepted: 08/24/2015] [Indexed: 12/25/2022]
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32
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Nakane A, Gotoh Y, Ichihara J, Nagata H. New screening strategy and analysis for identification of allosteric modulators for glucagon-like peptide-1 receptor using GLP-1 (9-36) amide. Anal Biochem 2015; 491:23-30. [PMID: 26341912 DOI: 10.1016/j.ab.2015.08.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 08/22/2015] [Accepted: 08/24/2015] [Indexed: 12/25/2022]
Abstract
The glucagon-like peptide-1 receptor (GLP-1R) is an important physiologic regulator of insulin secretion and a major therapeutic target for diabetes mellitus. GLP-1 (7-36) amide (active form of GLP-1) is truncated to GLP-1 (9-36) amide, which has been described as a weak agonist of GLP-1R and the major form of GLP-1 in the circulation. New classes of positive allosteric modulators (PAMs) for GLP-1R may offer improved therapeutic profiles. To identify these new classes, we developed novel and robust primary and secondary high-throughput screening (HTS) systems in which PAMs were identified to enhance the GLP-1R signaling induced by GLP-1 (9-36) amide. Screening enabled identification of two compounds, HIT-465 and HIT-736, which possessed new patterns of modulation of GLP-1R. We investigated the ability of these compounds to modify GLP-1R signaling enhanced GLP-1 (9-36) amide- and/or GLP-1 (7-36) amide-mediated cyclic adenosine monophosphate (cAMP) accumulation. These compounds also had unique profiles with regard to allosteric modulation of multiple downstream signaling (PathHunter β-arrestin signaling, PathHunter internalization signaling, microscopy-based internalization assay). We found allosteric modulation patterns to be obviously different among HIT-465, HIT-736, and Novo Nordisk compound 2. This work may enable the design of new classes of drug candidates by targeting modulation of GLP-1 (7-36) amide and GLP-1 (9-36) amide.
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Affiliation(s)
- Atsushi Nakane
- Genomic Science Laboratories, Sumitomo Dainippon Pharma, Konohana-ku, Osaka 554-0022, Japan
| | - Yusuke Gotoh
- Genomic Science Laboratories, Sumitomo Dainippon Pharma, Konohana-ku, Osaka 554-0022, Japan
| | - Junji Ichihara
- Genomic Science Laboratories, Sumitomo Dainippon Pharma, Konohana-ku, Osaka 554-0022, Japan
| | - Hidetaka Nagata
- Genomic Science Laboratories, Sumitomo Dainippon Pharma, Konohana-ku, Osaka 554-0022, Japan.
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Frederiksen TM, Sønderby P, Ryberg LA, Harris P, Bukrinski JT, Scharff-Poulsen AM, Elf-Lind MN, Peters GH. Oligomerization of a Glucagon-like Peptide 1 Analog: Bridging Experiment and Simulations. Biophys J 2015; 109:1202-13. [PMID: 26340816 DOI: 10.1016/j.bpj.2015.07.051] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 07/08/2015] [Accepted: 07/30/2015] [Indexed: 01/01/2023] Open
Abstract
The glucagon-like peptide 1 (GLP-1) analog, liraglutide, is a GLP-1 agonist and is used in the treatment of type-2 diabetes mellitus and obesity. From a pharmaceutical perspective, it is important to know the oligomerization state of liraglutide with respect to stability. Compared to GLP-1, liraglutide has an added fatty acid (FA) moiety that causes oligomerization of liraglutide as suggested by small-angle x-ray scattering (SAXS) and multiangle static light scattering (MALS) results. SAXS data suggested a global shape of a hollow elliptical cylinder of size hexa-, hepta-, or octamer, whereas MALS data indicate a hexamer. To elaborate further on the stability of these oligomers and the role of the FA chains, a series of molecular-dynamics simulations were carried out on 11 different hexa-, hepta-, and octameric systems. Our results indicate that interactions of the fatty acid chains contribute noticeably to the stabilization. The simulation results indicate that the heptamer with paired FA chains is the most stable oligomer when compared to the 10 other investigated structures. Theoretical SAXS curves extracted from the simulations qualitatively agree with the experimentally determined SAXS curves supporting the view that liraglutide forms heptamers in solution. In agreement with the SAXS data, the heptamer forms a water-filled oligomer of elliptical cylindrical shape.
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Affiliation(s)
- Tine M Frederiksen
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Pernille Sønderby
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Line A Ryberg
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Pernille Harris
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Denmark.
| | | | | | - Maria N Elf-Lind
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Günther H Peters
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Denmark.
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Association of Canonical Wnt/β-Catenin Pathway and Type 2 Diabetes: Genetic Epidemiological Study in Han Chinese. Nutrients 2015; 7:4763-77. [PMID: 26083111 PMCID: PMC4488812 DOI: 10.3390/nu7064763] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 05/28/2015] [Accepted: 06/03/2015] [Indexed: 12/28/2022] Open
Abstract
We aimed to investigate the associations of polymorphisms in Canonical Wnt/β-catenin pathway (WNT) signaling genes (including low-density lipoprotein-related protein 5 [LRP5] and transcription factor 7-like 2 [TCF7L2] gene) and the downstream gene glucagon (GCG) and risk of type 2 diabetes mellitus (T2DM) in a Han Chinese population. We genotyped the single nucleotide polymorphisms (SNPs) for LRP5, TCF7L2 and GCG gene were genotyped in 1842 patients with T2DM and 7777 normal glucose-tolerant healthy subjects. We used multifactor dimensionality reduction (MDR) and multiplicative logistic regression adjusting for sex, age, anthropometric measurements and lipid levels to investigate the gene-gene interactions for the risk of T2DM. Among the five SNPs in LRP5, the recessive model of rs7102273 and the haplotype GCTCC were associated with T2DM risk; the haplotype GCTTC was associated with decreased risk. For TCF7L2, the rs11196218 genotype GA and the haplotype CCG, TTG, TTA were associated with T2DM risk; whereas, the haplotype CTG and TCG were associated with decreased risk. Both MDR and multiplicative logistic regression revealed potential gene–gene interactions among LRP5, TCF7L2, and GCG associated with T2DM. The WNT signaling pathway may play a significant role in risk of T2DM in Han Chinese people.
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Liu J, Wang G, Jia Y, Xu Y. GLP-1 receptor agonists: effects on the progression of non-alcoholic fatty liver disease. Diabetes Metab Res Rev 2015; 31:329-35. [PMID: 25066109 DOI: 10.1002/dmrr.2580] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 06/15/2014] [Accepted: 07/06/2014] [Indexed: 12/21/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases, and its incidence has been increasing recently. In addition to hepatic complications, NAFLD is also recognized as an independent risk factor for cardiovascular disease. Unfortunately, the current therapies for NAFLD display variable efficacy; a novel and effective drug is urgently needed. Glucagon-like peptide-1 (GLP-1), a receptor agonist is a new drug approved for treating type 2 diabetes. Recently, these types of agents have shown a novel therapeutic effect on NAFLD. However, the mechanisms of GLP-1 receptor agonists on the treatment of NAFLD have not yet been explained precisely. Recent studies have demonstrated that GLP-1 reverses the progression of NAFLD not only indirectly through an incretin effect that improves key parameters involved in NAFLD, but also a direct effect on lipid metabolism of hepatocytes and inflammation in liver. In this review, we provided an overview of the role and mechanisms of GLP-1 in the therapy of NAFLD.
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Affiliation(s)
- Jia Liu
- Department of Endocrinology, Beijing Chaoyang Hospital Affiliated to Capital Medical University, Beijing, 100020, People's Republic of China
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36
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Heppner KM, Perez-Tilve D. GLP-1 based therapeutics: simultaneously combating T2DM and obesity. Front Neurosci 2015; 9:92. [PMID: 25852463 PMCID: PMC4367528 DOI: 10.3389/fnins.2015.00092] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2015] [Accepted: 03/05/2015] [Indexed: 12/13/2022] Open
Abstract
Glucagon-like peptide-1 (GLP-1) enhances meal-related insulin secretion, which lowers blood glucose excursions. In addition to its incretin action, GLP-1 acts on the GLP-1 receptor (GLP-1R) in the brain to suppress feeding. These combined actions of GLP-1R signaling cause improvements in glycemic control as well as weight loss in type II diabetes (T2DM) patients treated with GLP-1R agonists. This is a superior advantage of GLP-1R pharmaceuticals as many other drugs used to treat T2DM are weight neutral or actual cause weight gain. This review summarizes GLP-1R action on energy and glucose metabolism, the effectiveness of current GLP-1R agonists on weight loss in T2DM patients, as well as GLP-1R combination therapies.
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Affiliation(s)
- Kristy M Heppner
- Division of Diabetes, Obesity and Metabolism, Oregon National Primate Research Center, Oregon Health and Science University Beaverton, OR, USA
| | - Diego Perez-Tilve
- Department of Medicine, Metabolic Diseases Institute, University of Cincinnati Cincinnati, OH, USA
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37
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Heppner KM, Kirigiti M, Secher A, Paulsen SJ, Buckingham R, Pyke C, Knudsen LB, Vrang N, Grove KL. Expression and distribution of glucagon-like peptide-1 receptor mRNA, protein and binding in the male nonhuman primate (Macaca mulatta) brain. Endocrinology 2015; 156:255-67. [PMID: 25380238 PMCID: PMC4272390 DOI: 10.1210/en.2014-1675] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Glucagon-like peptide-1 (GLP-1) is released from endocrine L-cells lining the gut in response to food ingestion. However, GLP-1 is also produced in the nucleus of the solitary tract, where it acts as an anorectic neurotransmitter and key regulator of many autonomic and neuroendocrine functions. The expression and projections of GLP-1-producing neurons is highly conserved between rodent and primate brain, although a few key differences have been identified. The GLP-1 receptor (GLP-1R) has been mapped in the rodent brain, but no studies have described the distribution of GLP-1Rs in the nonhuman primate central nervous system. Here, we characterized the distribution of GLP-1R mRNA and protein in the adult macaque brain using in situ hybridization, radioligand receptor autoradiography, and immunohistochemistry with a primate specific GLP-1R antibody. Immunohistochemistry demonstrated that the GLP-1R is localized to cell bodies and fiber terminals in a very selective distribution throughout the brain. Consistent with the functional role of the GLP-1R system, we find the highest concentration of GLP-1R-immunoreactivity present in select hypothalamic and brainstem regions that regulate feeding, including the paraventricular and arcuate hypothalamic nuclei, as well as the area postrema, nucleus of the solitary tract, and dorsal motor nucleus of the vagus. Together, our data demonstrate that GLP-1R distribution is highly conserved between rodent and primate, although a few key species differences were identified, including the amygdala, where GLP-1R expression is much higher in primate than in rodent.
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Affiliation(s)
- Kristy M Heppner
- Division of Diabetes, Obesity, and Metabolism (K.M.H., M.K., R.B., K.L.G.), Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon 97006; Diabetes Research (A.S., C.P., L.B.K.), Novo Nordisk A/S, DK- 2760 Maaloev, Denmark; and Gubra ApS (S.J.P., N.V.), DK-2970, Hørsholm, Denmark
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38
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Finelli C, Padula MC, Martelli G, Tarantino G. Could the improvement of obesity-related co-morbidities depend on modified gut hormones secretion? World J Gastroenterol 2014; 20:16649-16664. [PMID: 25469034 PMCID: PMC4248209 DOI: 10.3748/wjg.v20.i44.16649] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 05/27/2014] [Accepted: 06/26/2014] [Indexed: 02/06/2023] Open
Abstract
Obesity and its associated diseases are a worldwide epidemic disease. Usual weight loss cures - as diets, physical activity, behavior therapy and pharmacotherapy - have been continuously implemented but still have relatively poor long-term success and mainly scarce adherence. Bariatric surgery is to date the most effective long term treatment for morbid obesity and it has been proven to reduce obesity-related co-morbidities, among them nonalcoholic fatty liver disease, and mortality. This article summarizes such variations in gut hormones following the current metabolic surgery procedures. The profile of gut hormonal changes after bariatric surgery represents a strategy for the individuation of the most performing surgical procedures to achieve clinical results. About this topic, experts suggest that the individuation of the crosslink among the gut hormones, microbiome, the obesity and the bariatric surgery could lead to new and more specific therapeutic interventions for severe obesity and its co-morbidities, also non surgical.
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The putative signal peptide of glucagon-like peptide-1 receptor is not required for receptor synthesis but promotes receptor expression. Biosci Rep 2014; 34:e00152. [PMID: 25330813 PMCID: PMC4240022 DOI: 10.1042/bsr20140120] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
GLP-1R (glucagon-like peptide-1 receptor) mediates the ‘incretin effect’ and many other anti-diabetic actions of its cognate ligand, GLP-1 (glucagon-like peptide-1). It belongs to the class B family of GPCRs (G protein-coupled receptors) and possesses an N-terminal putative SP (signal peptide). It has been reported that this sequence is required for the synthesis of GLP-1R and is cleaved after receptor synthesis. In the present study, we conducted an in-depth exploration towards the role of the putative SP in GLP-1R synthesis. A mutant GLP-1R without this sequence was expressed in HEK293 cells (human embryonic kidney 293 cells) and displayed normal functionality with respect to ligand binding and activation of adenylate cyclase. Thus the putative SP does not seem to be required for receptor synthesis. Immunoblotting analysis shows that the amount of GLP-1R synthesized in HEK293 cells is low when the putative SP is absent. This indicates that the role of the sequence is to promote the expression of GLP-1R. Furthermore, epitopes tagged at the N-terminal of GLP-1R are detectable by immunofluorescence and immunoblotting in our experiments. In conclusion, the present study points to different roles of SP in GLP-1R expression which broadens our understanding of the functionality of this putative SP of GLP-1R and possibly other Class B GPCRs.
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40
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Dong M, Koole C, Wootten D, Sexton PM, Miller LJ. Structural and functional insights into the juxtamembranous amino-terminal tail and extracellular loop regions of class B GPCRs. Br J Pharmacol 2014; 171:1085-101. [PMID: 23889342 DOI: 10.1111/bph.12293] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 06/22/2013] [Accepted: 06/29/2013] [Indexed: 12/24/2022] Open
Abstract
Class B guanine nucleotide-binding protein GPCRs share heptahelical topology and signalling via coupling with heterotrimeric G proteins typical of the entire superfamily of GPCRs. However, they also exhibit substantial structural differences from the more extensively studied class A GPCRs. Even their helical bundle region, most conserved across the superfamily, is predicted to differ from that of class A GPCRs. Much is now known about the conserved structure of the amino-terminal domain of class B GPCRs, coming from isolated NMR and crystal structures, but the orientation of that domain relative to the helical bundle is unknown, and even less is understood about the conformations of the juxtamembranous amino-terminal tail or of the extracellular loops linking the transmembrane segments. We now review what is known about the structure and function of these regions of class B GPCRs. This comes from indirect analysis of structure-function relationships elucidated by mutagenesis and/or ligand modification and from the more direct analysis of spatial approximation coming from photoaffinity labelling and cysteine trapping studies. Also reviewed are the limited studies of structure of some of these regions. No dominant theme was recognized for the structures or functional roles of distinct regions of these juxtamembranous portions of the class B GPCRs. Therefore, it is likely that a variety of molecular strategies can be engaged for docking of agonist ligands and for initiation of conformational changes in these receptors that would be expected to converge to a common molecular mechanism for activation of intracellular signalling cascades.
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Affiliation(s)
- M Dong
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
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41
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Zhang M, Robitaille M, Showalter AD, Huang X, Liu Y, Bhattacharjee A, Willard FS, Han J, Froese S, Wei L, Gaisano HY, Angers S, Sloop KW, Dai FF, Wheeler MB. Progesterone receptor membrane component 1 is a functional part of the glucagon-like peptide-1 (GLP-1) receptor complex in pancreatic β cells. Mol Cell Proteomics 2014; 13:3049-62. [PMID: 25044020 DOI: 10.1074/mcp.m114.040196] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Glucagon-like peptide-1 (GLP-1) is an incretin hormone that regulates glucose homeostasis. Because of their direct stimulation of insulin secretion from pancreatic β cells, GLP-1 receptor (GLP-1R) agonists are now important therapeutic options for the treatment of type 2 diabetes. To better understand the mechanisms that control the insulinotropic actions of GLP-1, affinity purification and mass spectrometry (AP-MS) were employed to uncover potential proteins that functionally interact with the GLP-1R. AP-MS performed on Chinese hamster ovary cells or MIN6 β cells, both expressing the human GLP-1R, revealed 99 proteins potentially associated with the GLP-1R. Three novel GLP-1R interactors (PGRMC1, Rab5b, and Rab5c) were further validated through co-immunoprecipitation/immunoblotting, fluorescence resonance energy transfer, and immunofluorescence. Functional studies revealed that overexpression of PGRMC1, a novel cell surface receptor that associated with liganded GLP-1R, enhanced GLP-1-induced insulin secretion (GIIS) with the most robust effect. Knockdown of PGRMC1 in β cells decreased GIIS, indicative of positive interaction with GLP-1R. To gain insight mechanistically, we demonstrated that the cell surface PGRMC1 ligand P4-BSA increased GIIS, whereas its antagonist AG-205 decreased GIIS. It was then found that PGRMC1 increased GLP-1-induced cAMP accumulation. PGRMC1 activation and GIIS induced by P4-BSA could be blocked by inhibition of adenylyl cyclase/EPAC signaling or the EGF receptor-PI3K signal transduction pathway. These data reveal a dual mechanism for PGRMC1-increased GIIS mediated through cAMP and EGF receptor signaling. In conclusion, we identified several novel GLP-1R interacting proteins. PGRMC1 expressed on the cell surface of β cells was shown to interact with the activated GLP-1R to enhance the insulinotropic actions of GLP-1.
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Affiliation(s)
- Ming Zhang
- From the ‡Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Canada, M5S 1A8; §Division of Advanced Diagnosis, Toronto General Research Institute, Toronto, Canada, M5G 1C7
| | - Mélanie Robitaille
- ¶Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, and Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, Canada, M5S 3M2
| | - Aaron D Showalter
- ‖Endocrine Discovery, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana, 46285
| | - Xinyi Huang
- From the ‡Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Canada, M5S 1A8; §Division of Advanced Diagnosis, Toronto General Research Institute, Toronto, Canada, M5G 1C7
| | - Ying Liu
- From the ‡Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Canada, M5S 1A8
| | - Alpana Bhattacharjee
- From the ‡Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Canada, M5S 1A8
| | - Francis S Willard
- ‖‖Quantitative Biology, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana, 46285
| | - Junfeng Han
- **Department of Endocrinology and Metabolism, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, China 200233
| | - Sean Froese
- From the ‡Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Canada, M5S 1A8; §Division of Advanced Diagnosis, Toronto General Research Institute, Toronto, Canada, M5G 1C7
| | - Li Wei
- **Department of Endocrinology and Metabolism, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, China 200233
| | - Herbert Y Gaisano
- ‡‡Department of Medicine, Faculty of Medicine, University of Toronto, Toronto, Canada, M5S 1A8
| | - Stéphane Angers
- ¶Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, and Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, Canada, M5S 3M2
| | - Kyle W Sloop
- ‖Endocrine Discovery, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana, 46285
| | - Feihan F Dai
- From the ‡Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Canada, M5S 1A8;
| | - Michael B Wheeler
- From the ‡Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Canada, M5S 1A8; §Division of Advanced Diagnosis, Toronto General Research Institute, Toronto, Canada, M5G 1C7;
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42
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Nolte WM, Fortin JP, Stevens BD, Aspnes GE, Griffith DA, Hoth LR, Ruggeri RB, Mathiowetz AM, Limberakis C, Hepworth D, Carpino PA. A potentiator of orthosteric ligand activity at GLP-1R acts via covalent modification. Nat Chem Biol 2014; 10:629-31. [PMID: 24997604 DOI: 10.1038/nchembio.1581] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 06/10/2014] [Indexed: 02/06/2023]
Abstract
We report that 4-(3-(benzyloxy)phenyl)-2-ethylsulfinyl-6-(trifluoromethyl)pyrimidine (BETP), which behaves as a positive allosteric modulator at the glucagon-like peptide-1 receptor (GLP-1R), covalently modifies cysteines 347 and 438 in GLP-1R. C347, located in intracellular loop 3 of GLP-1R, is critical to the activity of BETP and a structurally distinct GLP-1R ago-allosteric modulator, N-(tert-butyl)-6,7-dichloro-3-(methylsulfonyl)quinoxalin-2-amine. We further show that substitution of cysteine for phenylalanine 345 in the glucagon receptor is sufficient to confer sensitivity to BETP.
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Affiliation(s)
- Whitney M Nolte
- Worldwide Medicinal Chemistry, Pfizer PharmaTherapeutics Research and Development, Cambridge, Massachusetts, USA
| | - Jean-Philippe Fortin
- Cardiovascular and Metabolic Diseases Research Unit, Pfizer PharmaTherapeutics Research and Development, Cambridge, Massachusetts, USA
| | - Benjamin D Stevens
- Worldwide Medicinal Chemistry, Pfizer PharmaTherapeutics Research and Development, Cambridge, Massachusetts, USA
| | - Gary E Aspnes
- Worldwide Medicinal Chemistry, Pfizer PharmaTherapeutics Research and Development, Groton, Connecticut, USA
| | - David A Griffith
- Worldwide Medicinal Chemistry, Pfizer PharmaTherapeutics Research and Development, Cambridge, Massachusetts, USA
| | - Lise R Hoth
- Structural Biology and Biophysics Group, Center for Chemistry Innovation and Excellence, Worldwide Medicinal Chemistry, Pfizer PharmaTherapeutics Research and Development, Groton, Connecticut, USA
| | - Roger B Ruggeri
- Worldwide Medicinal Chemistry, Pfizer PharmaTherapeutics Research and Development, Cambridge, Massachusetts, USA
| | - Alan M Mathiowetz
- Worldwide Medicinal Chemistry, Pfizer PharmaTherapeutics Research and Development, Cambridge, Massachusetts, USA
| | - Chris Limberakis
- Worldwide Medicinal Chemistry, Pfizer PharmaTherapeutics Research and Development, Groton, Connecticut, USA
| | - David Hepworth
- Worldwide Medicinal Chemistry, Pfizer PharmaTherapeutics Research and Development, Cambridge, Massachusetts, USA
| | - Philip A Carpino
- Worldwide Medicinal Chemistry, Pfizer PharmaTherapeutics Research and Development, Cambridge, Massachusetts, USA
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Morris LC, Days EL, Turney M, Mi D, Lindsley CW, Weaver CD, Niswender KD. A Duplexed High-Throughput Screen to Identify Allosteric Modulators of the Glucagon-Like Peptide 1 and Glucagon Receptors. JOURNAL OF BIOMOLECULAR SCREENING 2014; 19:847-58. [PMID: 24525870 PMCID: PMC4306651 DOI: 10.1177/1087057114520971] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 12/31/2013] [Indexed: 11/16/2022]
Abstract
Injectable, degradation-resistant peptide agonists for the glucagon-like peptide 1 (GLP-1) receptor (GLP-1R), such as exenatide and liraglutide, activate the GLP-1R via a complex orthosteric-binding site and are effective therapeutics for glycemic control in type 2 diabetes. Orally bioavailable orthosteric small-molecule agonists are unlikely to be developed, whereas positive allosteric modulators (PAMs) may offer an improved therapeutic profile. We hypothesize that allosteric modulators of the GLP-1R would increase the potency and efficacy of native GLP-1 in a spatial and temporally preserved manner and/or may improve efficacy or side effects of injectable analogs. We report the design, optimization, and initial results of a duplexed high-throughput screen in which cell lines overexpressing either the GLP-1R or the glucagon receptor were coplated, loaded with a calcium-sensitive dye, and probed in a three-phase assay to identify agonists, antagonists, and potentiators of GLP-1, and potentiators of glucagon. 175,000 compounds were initially screened, and progression through secondary assays yielded 98 compounds with a variety of activities at the GLP-1R. Here, we describe five compounds possessing different patterns of modulation of the GLP-1R. These data uncover PAMs that may offer a drug-development pathway to enhancing in vivo efficacy of both endogenous GLP-1 and peptide analogs.
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Affiliation(s)
- Lindsey C Morris
- Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Emily L Days
- Vanderbilt Institute for Chemical Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Maxine Turney
- Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Dehui Mi
- Vanderbilt Institute for Chemical Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Craig W Lindsley
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN, USA Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - C David Weaver
- Vanderbilt Institute for Chemical Biology, Vanderbilt University School of Medicine, Nashville, TN, USA Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Kevin D Niswender
- Tennessee Valley Healthcare System, Nashville, TN, USA Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University School of Medicine, Nashville, TN, USA
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44
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Abstract
BACKGROUND The obesity epidemic is driving the increased prevalence of type 2 diabetes mellitus (T2DM), and the vast majority of patients with T2DM are overweight or obese. Excess body weight is associated with the risk of cardiometabolic complications, which are major causes of morbidity and mortality in T2DM. AIMS To review evidence about effects of weight loss in pre-diabetes and established T2DM. RESULTS In prediabetes, weight loss has been shown to delay the onset or decrease the risk of T2DM, while in established T2DM weight loss has been shown to improve glycaemic control, with severe calorie restriction even reversing the progression of T2DM. Observational studies support the reduction in cardiovascular risk factors following weight loss in patients with T2DM. However, data from the randomised Look AHEAD trial revealed intensive weight loss interventions did not reduce the rate of cardiovascular events in overweight or obese adults with T2DM, and secondary analyses of other large cardiovascular outcomes trials have also been inconclusive. However, besides cardiovascular risk, other documented benefits of weight loss in T2DM include improvements in quality of life, mobility, and physical and sexual function. CONCLUSIONS Physicians should encourage weight loss in all overweight patients with or at risk of T2DM, and should consider the impact on weight when choosing the most appropriate glucose-lowering therapies for these patients.
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45
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Geerling JJ, Boon MR, Kooijman S, Parlevliet ET, Havekes LM, Romijn JA, Meurs IM, Rensen PCN. Sympathetic nervous system control of triglyceride metabolism: novel concepts derived from recent studies. J Lipid Res 2014; 55:180-9. [PMID: 24285857 PMCID: PMC3886657 DOI: 10.1194/jlr.r045013] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 11/27/2013] [Indexed: 12/16/2022] Open
Abstract
Important players in triglyceride (TG) metabolism include the liver (production), white adipose tissue (WAT) (storage), heart and skeletal muscle (combustion to generate ATP), and brown adipose tissue (BAT) (combustion toward heat), the collective action of which determine plasma TG levels. Interestingly, recent evidence points to a prominent role of the hypothalamus in TG metabolism through innervating the liver, WAT, and BAT mainly via sympathetic branches of the autonomic nervous system. Here, we review the recent findings in the area of sympathetic control of TG metabolism. Various neuronal populations, such as neuropeptide Y (NPY)-expressing neurons and melanocortin-expressing neurons, as well as peripherally produced hormones (i.e., GLP-1, leptin, and insulin), modulate sympathetic outflow from the hypothalamus toward target organs and thereby influence peripheral TG metabolism. We conclude that sympathetic stimulation in general increases lipolysis in WAT, enhances VLDL-TG production by the liver, and increases the activity of BAT with respect to lipolysis of TG, followed by combustion of fatty acids toward heat. Moreover, the increased knowledge about the involvement of the neuroendocrine system in TG metabolism presented in this review offers new therapeutic options to fight hypertriglyceridemia by specifically modulating sympathetic nervous system outflow toward liver, BAT, or WAT.
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Affiliation(s)
- Janine J. Geerling
- Departments of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Mariëtte R. Boon
- Departments of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Sander Kooijman
- Departments of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Edwin T. Parlevliet
- Departments of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, The Netherlands
- Department of Medicine, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Louis M. Havekes
- Departments of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, The Netherlands
- Gaubius Laboratory, Netherlands Organization for Applied Scientific Research - Metabolic Health Research, Leiden, The Netherlands
| | - Johannes A. Romijn
- Department of Medicine, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Illiana M. Meurs
- Departments of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Patrick C. N. Rensen
- Departments of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, The Netherlands
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46
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Denton EV, Craig CJ, Pongratz RL, Appelbaum JS, Doerner AE, Narayanan A, Shulman GI, Cline GW, Schepartz A. A β-peptide agonist of the GLP-1 receptor, a class B GPCR. Org Lett 2013; 15:5318-21. [PMID: 24087900 DOI: 10.1021/ol402568j] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Previous work has shown that certain β(3)-peptides can effectively mimic the side chain display of an α-helix and inhibit interactions between proteins, both in vitro and in cultured cells. Here we describe a β(3)-peptide analog of GLP-1, CC-3(Act), that interacts with the GLP-1R extracellular domain (nGLP-1R) in vitro in a manner that competes with exendin-4 and induces GLP-1R-dependent cAMP signaling in cultured CHO-K1 cells expressing GLP-1R.
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Affiliation(s)
- Elizabeth V Denton
- Department of Chemistry, Yale University , New Haven, Connecticut 06511, United States, Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut 06536, United States, Department of Cell Biology, Yale University School of Medicine , New Haven, Connecticut 06520, United States, Department of Cellular and Molecular Physiology, Yale University School of Medicine , New Haven, Connecticut 06520, United States, Howard Hughes Medical Institute, Yale University School of Medicine , New Haven, Connecticut 06520, United States, and Department of Molecular, Cellular and Developmental Biology, Yale University , New Haven, Connecticut 06520, United States
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47
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Huang X, Dai FF, Gaisano G, Giglou K, Han J, Zhang M, Kittanakom S, Wong V, Wei L, Showalter AD, Sloop KW, Stagljar I, Wheeler MB. The identification of novel proteins that interact with the GLP-1 receptor and restrain its activity. Mol Endocrinol 2013; 27:1550-63. [PMID: 23864651 DOI: 10.1210/me.2013-1047] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Glucagon-like peptide 1 receptor (GLP-1R) controls diverse physiological functions in tissues including the pancreatic islets, brain, and heart. To understand the mechanisms that control glucagon-like peptide 1 (GLP-1) signaling better, we sought to identify proteins that interact with the GLP-1R using a membrane-based split ubiquitin yeast two-hybrid (MYTH) assay. A screen of a human fetal brain cDNA prey library with an unliganded human GLP-1R as bait in yeast revealed 38 novel interactor protein candidates. These interactions were confirmed in mammalian Chinese hamster ovarian cells by coimmunoprecipitation. Immunofluorescence was used to show subcellular colocalization of the interactors with GLP-1R. Cluster analysis revealed that the interactors were primarily associated with signal transduction, metabolism, and cell development. When coexpressed with the GLP-1R in Chinese hamster ovarian cells, 15 interactors significantly altered GLP-1-induced cAMP accumulation. Surprisingly, all 15 proteins inhibited GLP-1-activated cAMP. Given GLP-1's prominent role as an incretin, we then focused on 3 novel interactors, SLC15A4, APLP1, and AP2M1, because they are highly expressed and localized to the membrane in mouse insulinoma β-cells. Small interfering RNA-mediated knockdown of each candidate gene significantly enhanced GLP-1-induced insulin secretion. In conclusion, we have generated a novel GLP-1R-protein interactome, identifying several interactors that suppress GLP-1R signaling. We suggest that the inhibition of these interactors may serve as a novel strategy to enhance GLP-1R activity.
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Affiliation(s)
- X Huang
- Department of Physiology and Medicine, Medical Sciences Building, 1 King's College Circle, University of Toronto, Ontario, Canada M5S 1A8
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48
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Kaspar AA, Reichert JM. Future directions for peptide therapeutics development. Drug Discov Today 2013; 18:807-17. [PMID: 23726889 DOI: 10.1016/j.drudis.2013.05.011] [Citation(s) in RCA: 517] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 04/27/2013] [Accepted: 05/20/2013] [Indexed: 10/26/2022]
Abstract
The notable expansion of peptide therapeutics development in the late 1990s and the 2000s led to an unprecedented number of marketing approvals in 2012 and has provided a robust pipeline that should deliver numerous approvals during the remainder of the 2010s. To document the current status of the pipeline, we collected data for peptide therapeutics in clinical studies and regulatory review, as well as those recently approved. In this Foundation review, we provide an overview of the pipeline, including therapeutic area and molecular targets, with a focus on glucagon-like peptide 1 receptor agonists. Areas for potential expansion, for example constrained peptides and peptide-drug conjugates, are profiled.
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Affiliation(s)
- Allan A Kaspar
- CovX/Pfizer Worldwide Research and Development, 9381 Judicial Drive, Suite 200, San Diego, CA 92121, USA
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49
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Ghosal S, Myers B, Herman JP. Role of central glucagon-like peptide-1 in stress regulation. Physiol Behav 2013; 122:201-7. [PMID: 23623992 DOI: 10.1016/j.physbeh.2013.04.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Revised: 03/20/2013] [Accepted: 04/16/2013] [Indexed: 01/12/2023]
Abstract
Glucagon-like peptide 1 (GLP-1) is best known as an incretin hormone, secreted from L cells in the intestine in response to nutrient ingestion to stimulate glucose-dependent insulin secretion. However, GLP-1 is also expressed in neurons, and plays a major role in regulation of homeostatic function within the central nervous system (CNS). This review summarizes our current state of knowledge on the role GLP-1 plays in neural coordination of the organismal stress response. In the brain, the primary locus of GLP-1 production is in the caudal nucleus of the solitary tract (NTS) and the ventrolateral medulla of the hindbrain. GLP-1 immunoreactive fibers directly innervate hypophysiotrophic corticotropin-releasing hormone (CRH) neurons in the hypothalamic paraventricular nucleus (PVN), placing GLP-1 in prime position to integrate hypothalamo-pituitary-adrenocortical responses. Exogenous central GLP-1 activates HPA axis stress responses, and responses to a variety of stressors can be blocked by a GLP-1 receptor (GLP-1R) antagonist, confirming an excitatory role in glucocorticoid secretion. In addition, central infusion of GLP-1R agonist increases heart rate and blood pressure, and activates hypothalamic and brainstem neurons innervating sympathetic preganglionic neurons, suggesting a sympathoexcitatory role of GLP-1 in the CNS. Bioavailability of preproglucagon (PPG) mRNA and GLP-1 peptide is reduced by exogenous or endogenous glucocorticoid secretion, perhaps as a mechanism to reduce GLP-1-mediated stress excitation. Altogether, the data suggest that GLP-1 plays a key role in activation of stress responses, which may be connected with its role in central regulation of energy homeostasis.
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Affiliation(s)
- Sriparna Ghosal
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Reading Campus, OH 45237-0506, USA.
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50
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Clardy-James S, Chepurny OG, Leech CA, Holz GG, Doyle RP. Synthesis, characterization and pharmacodynamics of vitamin-B(12)-conjugated glucagon-like peptide-1. ChemMedChem 2012. [PMID: 23203941 DOI: 10.1002/cmdc.201200461] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Clearing the way: Glucagon-like peptide-1 (GLP-1) receptor agonists are proving a potent weapon in the treatment of type II diabetes. A new vitamin B(12)-GLP-1 conjugate is investigated and shown to have insulinotropic properties similar to the unmodified peptide. These results are critical to the exploitation of the vitamin B(12) oral uptake pathway for peptide delivery.
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Affiliation(s)
- Susan Clardy-James
- Department of Chemistry, Syracuse University, 111 College Place Syracuse, NY 13244, USA
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