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Wargent ET, Kępczyńska MA, Kaspersen MH, Ulven ER, Arch JRS, Ulven T, Stocker CJ. Chronic administration of hydrolysed pine nut oil to mice improves insulin sensitivity and glucose tolerance and increases energy expenditure via a free fatty acid receptor 4-dependent mechanism. Br J Nutr 2024:1-8. [PMID: 38751244 DOI: 10.1017/s0007114524000965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2024]
Abstract
A healthy diet is at the forefront of measures to prevent type 2 diabetes. Certain vegetable and fish oils, such as pine nut oil (PNO), have been demonstrated to ameliorate the adverse metabolic effects of a high-fat diet. The present study investigates the involvement of the free fatty acid receptors 1 (FFAR1) and 4 (FFAR4) in the chronic activity of hydrolysed PNO (hPNO) on high-fat diet-induced obesity and insulin resistance. Male C57BL/6J wild-type, FFAR1 knockout (-/-) and FFAR4-/- mice were placed on 60 % high-fat diet for 3 months. Mice were then dosed hPNO for 24 d, during which time body composition, energy intake and expenditure, glucose tolerance and fasting plasma insulin, leptin and adiponectin were measured. hPNO improved glucose tolerance and decreased plasma insulin in the wild-type and FFAR1-/- mice, but not the FFAR4-/- mice. hPNO also decreased high-fat diet-induced body weight gain and fat mass, whilst increasing energy expenditure and plasma adiponectin. None of these effects on energy balance were statistically significant in FFAR4-/- mice, but it was not shown that they were significantly less than in wild-type mice. In conclusion, chronic hPNO supplementation reduces the metabolically detrimental effects of high-fat diet on obesity and insulin resistance in a manner that is dependent on the presence of FFAR4.
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Affiliation(s)
- Edward Taynton Wargent
- Institute of Translational Medicine, Clore Laboratory, University of Buckingham, Buckingham, MK18 1EG, UK
| | - Małgorzata A Kępczyńska
- Institute of Translational Medicine, Clore Laboratory, University of Buckingham, Buckingham, MK18 1EG, UK
| | - Mads H Kaspersen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense, Denmark
| | - Elisabeth Rexen Ulven
- Department of Drug Design and Pharmacology, University of Copenhagen, 2100Copenhagen, Denmark
| | - Jonathan R S Arch
- Institute of Translational Medicine, Clore Laboratory, University of Buckingham, Buckingham, MK18 1EG, UK
| | - Trond Ulven
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense, Denmark
- Department of Drug Design and Pharmacology, University of Copenhagen, 2100Copenhagen, Denmark
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Varney MJ, Benovic JL. The Role of G Protein-Coupled Receptors and Receptor Kinases in Pancreatic β-Cell Function and Diabetes. Pharmacol Rev 2024; 76:267-299. [PMID: 38351071 PMCID: PMC10877731 DOI: 10.1124/pharmrev.123.001015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 12/01/2023] [Accepted: 12/07/2023] [Indexed: 02/16/2024] Open
Abstract
Type 2 diabetes (T2D) mellitus has emerged as a major global health concern that has accelerated in recent years due to poor diet and lifestyle. Afflicted individuals have high blood glucose levels that stem from the inability of the pancreas to make enough insulin to meet demand. Although medication can help to maintain normal blood glucose levels in individuals with chronic disease, many of these medicines are outdated, have severe side effects, and often become less efficacious over time, necessitating the need for insulin therapy. G protein-coupled receptors (GPCRs) regulate many physiologic processes, including blood glucose levels. In pancreatic β cells, GPCRs regulate β-cell growth, apoptosis, and insulin secretion, which are all critical in maintaining sufficient β-cell mass and insulin output to ensure euglycemia. In recent years, new insights into the signaling of incretin receptors and other GPCRs have underscored the potential of these receptors as desirable targets in the treatment of diabetes. The signaling of these receptors is modulated by GPCR kinases (GRKs) that phosphorylate agonist-activated GPCRs, marking the receptor for arrestin binding and internalization. Interestingly, genome-wide association studies using diabetic patient cohorts link the GRKs and arrestins with T2D. Moreover, recent reports show that GRKs and arrestins expressed in the β cell serve a critical role in the regulation of β-cell function, including β-cell growth and insulin secretion in both GPCR-dependent and -independent pathways. In this review, we describe recent insights into GPCR signaling and the importance of GRK function in modulating β-cell physiology. SIGNIFICANCE STATEMENT: Pancreatic β cells contain a diverse array of G protein-coupled receptors (GPCRs) that have been shown to improve β-cell function and survival, yet only a handful have been successfully targeted in the treatment of diabetes. This review discusses recent advances in our understanding of β-cell GPCR pharmacology and regulation by GPCR kinases while also highlighting the necessity of investigating islet-enriched GPCRs that have largely been unexplored to unveil novel treatment strategies.
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Affiliation(s)
- Matthew J Varney
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Jeffrey L Benovic
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania
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3
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Mohammad Nezhady MA, Modaresinejad M, Zia A, Chemtob S. Versatile lactate signaling via HCAR1: a multifaceted GPCR involved in many biological processes. Am J Physiol Cell Physiol 2023; 325:C1502-C1515. [PMID: 37899751 DOI: 10.1152/ajpcell.00346.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/17/2023] [Accepted: 10/17/2023] [Indexed: 10/31/2023]
Abstract
G-coupled protein receptors (GPCRs) are the ultimate refuge of pharmacology and medicine as more than 40% of all marketed drugs are directly targeting these receptors. Through cell surface expression, they are at the forefront of cellular communication with the outside world. Metabolites among the conveyors of this communication are becoming more prominent with the recognition of them as ligands for GPCRs. HCAR1 is a GPCR conveyor of lactate. It is a class A GPCR coupled to Gαi which reduces cellular cAMP along with the downstream Gβγ signaling. It was first found to inhibit lipolysis, and lately has been implicated in diverse cellular processes, including neural activities, angiogenesis, inflammation, vision, cardiovascular function, stem cell proliferation, and involved in promoting pathogenesis for different conditions, such as cancer. Other than signaling from the plasma membrane, HCAR1 shows nuclear localization with different location-biased activities therein. Although different functions for HCAR1 are being discovered, its cell and molecular mechanisms are yet ill understood. Here, we provide a comprehensive review on HCAR1, which covers the literature on the subject, and discusses its importance and relevance in various biological phenomena.
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Affiliation(s)
- Mohammad Ali Mohammad Nezhady
- Molecular Biology Program, Faculty of Medicine, Université de Montréal, Montreal, Quebec, Canada
- Research Center of Centre Hospitalier Universitaire Sainte-Justine, Montreal, Quebec, Canada
| | - Monir Modaresinejad
- Research Center of Centre Hospitalier Universitaire Sainte-Justine, Montreal, Quebec, Canada
- Biomedical Sciences Program, Faculty of Medicine, Université de Montréal, Montreal, Quebec, Canada
| | - Aliabbas Zia
- Research Center of Centre Hospitalier Universitaire Sainte-Justine, Montreal, Quebec, Canada
- Department of Pharmacology, Université de Montréal, Montreal, Quebec, Canada
| | - Sylvain Chemtob
- Molecular Biology Program, Faculty of Medicine, Université de Montréal, Montreal, Quebec, Canada
- Research Center of Centre Hospitalier Universitaire Sainte-Justine, Montreal, Quebec, Canada
- Department of Pharmacology, Université de Montréal, Montreal, Quebec, Canada
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4
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Hrovatin K, Bastidas-Ponce A, Bakhti M, Zappia L, Büttner M, Salinno C, Sterr M, Böttcher A, Migliorini A, Lickert H, Theis FJ. Delineating mouse β-cell identity during lifetime and in diabetes with a single cell atlas. Nat Metab 2023; 5:1615-1637. [PMID: 37697055 PMCID: PMC10513934 DOI: 10.1038/s42255-023-00876-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 07/26/2023] [Indexed: 09/13/2023]
Abstract
Although multiple pancreatic islet single-cell RNA-sequencing (scRNA-seq) datasets have been generated, a consensus on pancreatic cell states in development, homeostasis and diabetes as well as the value of preclinical animal models is missing. Here, we present an scRNA-seq cross-condition mouse islet atlas (MIA), a curated resource for interactive exploration and computational querying. We integrate over 300,000 cells from nine scRNA-seq datasets consisting of 56 samples, varying in age, sex and diabetes models, including an autoimmune type 1 diabetes model (NOD), a glucotoxicity/lipotoxicity type 2 diabetes model (db/db) and a chemical streptozotocin β-cell ablation model. The β-cell landscape of MIA reveals new cell states during disease progression and cross-publication differences between previously suggested marker genes. We show that β-cells in the streptozotocin model transcriptionally correlate with those in human type 2 diabetes and mouse db/db models, but are less similar to human type 1 diabetes and mouse NOD β-cells. We also report pathways that are shared between β-cells in immature, aged and diabetes models. MIA enables a comprehensive analysis of β-cell responses to different stressors, providing a roadmap for the understanding of β-cell plasticity, compensation and demise.
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Affiliation(s)
- Karin Hrovatin
- Institute of Computational Biology, Helmholtz Zentrum München, Neuherberg, Germany
- TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Aimée Bastidas-Ponce
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Medical Faculty, Technical University of Munich, Munich, Germany
| | - Mostafa Bakhti
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Luke Zappia
- Institute of Computational Biology, Helmholtz Zentrum München, Neuherberg, Germany
- Department of Mathematics, Technical University of Munich, Garching, Germany
| | - Maren Büttner
- Institute of Computational Biology, Helmholtz Zentrum München, Neuherberg, Germany
- Genomics and Immunoregulation, Life & Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany
- Systems Medicine, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Bonn, Germany
| | - Ciro Salinno
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Medical Faculty, Technical University of Munich, Munich, Germany
| | - Michael Sterr
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Anika Böttcher
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Adriana Migliorini
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- McEwen Stem Cell Institute, University Health Network (UHN), Toronto, Ontario, Canada
| | - Heiko Lickert
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany.
- German Center for Diabetes Research (DZD), Neuherberg, Germany.
- Medical Faculty, Technical University of Munich, Munich, Germany.
| | - Fabian J Theis
- Institute of Computational Biology, Helmholtz Zentrum München, Neuherberg, Germany.
- TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany.
- Department of Mathematics, Technical University of Munich, Garching, Germany.
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5
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Oteng AB, Liu L. GPCR-mediated effects of fatty acids and bile acids on glucose homeostasis. Front Endocrinol (Lausanne) 2023; 14:1206063. [PMID: 37484954 PMCID: PMC10360933 DOI: 10.3389/fendo.2023.1206063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 06/20/2023] [Indexed: 07/25/2023] Open
Abstract
Fatty acids and glucose are key biomolecules that share several commonalities including serving as energy substrates and as signaling molecules. Fatty acids can be synthesized endogenously from intermediates of glucose catabolism via de-novo lipogenesis. Bile acids are synthesized endogenously in the liver from the biologically important lipid molecule, cholesterol. Evidence abounds that fatty acids and bile acids play direct and indirect roles in systemic glucose homeostasis. The tight control of plasma glucose levels during postprandial and fasted states is principally mediated by two pancreatic hormones, insulin and glucagon. Here, we summarize experimental studies on the endocrine effects of fatty acids and bile acids, with emphasis on their ability to regulate the release of key hormones that regulate glucose metabolism. We categorize the heterogenous family of fatty acids into short chain fatty acids (SCFAs), unsaturated, and saturated fatty acids, and highlight that along with bile acids, these biomolecules regulate glucose homeostasis by serving as endogenous ligands for specific G-protein coupled receptors (GPCRs). Activation of these GPCRs affects the release of incretin hormones by enteroendocrine cells and/or the secretion of insulin, glucagon, and somatostatin by pancreatic islets, all of which regulate systemic glucose homeostasis. We deduce that signaling induced by fatty acids and bile acids is necessary to maintain euglycemia to prevent metabolic diseases such as type-2 diabetes and related metabolic disorders.
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6
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Prado TP, Jara CP, Dias Bóbbo VC, Carraro RS, Sidarta-Oliveira D, de Mendonça GRA, Velloso LA, Araújo EP. A Free Fatty Acid Synthetic Agonist Accelerates Wound Healing and Improves Scar Quality in Mice. Biol Res Nurs 2023; 25:353-366. [PMID: 36444640 DOI: 10.1177/10998004221142331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
BACKGROUND Impaired wound healing is a health problem around the world, and the search for a novel product to repair wounded skin is a major topic in the field. GW9508 is a synthetic molecule described as a selective agonist of free fatty acid receptors (FFARs) 1 and 4, and there is evidence of its anti-inflammatory effects on several organs of the body. PURPOSE Here, we aimed to evaluate the effects of topical GW9508 on wound healing in mice. RESEARCH DESIGN First, we used bioinformatic methods to determine the expression of FFAR1 and FFAR4 mRNA in the skin from a human cell atlas assembled with single-cell transcriptomes. Next, we employed 6-week-old C57BL6J mice with 2 wounds inflicted in the back. The mice were randomly divided into 2 groups, a control group, which received topical vehicle, and a treatment group, which received GW9508, for 12 days. The wound was monitored by photographic documentation every 2 days, and samples were collected at day 6 and 12 post injury for RT-PCR, western blot and histology analyses. RESULTS FFAR1 and FFAR4 mRNA are expressed in skin cells in similar amounts to those in other tissues. Topical GW9508 accelerated wound healing and decreased gene expression of IL-10 and metalloproteinase 9 on days 6 and 12 post injury. It increased the quantity of Collagen I and improved the organization of collagen fibres. Conclusions: Our results show that GW9508 could be an attractive drug treatment for wounded skin. Future studies need to be performed to assess the impact of GW9508 in chronic wound models.
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Affiliation(s)
- Thais P Prado
- Nursing School, Laboratory of Cell Signaling Obesity and Comorbidities Center, OCRC, University of Campinas, Campinas, Brazil
- Faculty of Medical Sciences, Laboratory of Cell Signaling, Obesity and Comorbidities Center - OCRC, University of Campinas, Campinas, Brazil
| | - Carlos P Jara
- Nursing School, Laboratory of Cell Signaling Obesity and Comorbidities Center, OCRC, University of Campinas, Campinas, Brazil
- Faculty of Medical Sciences, Laboratory of Cell Signaling, Obesity and Comorbidities Center - OCRC, University of Campinas, Campinas, Brazil
| | - Vanessa C Dias Bóbbo
- Nursing School, Laboratory of Cell Signaling Obesity and Comorbidities Center, OCRC, University of Campinas, Campinas, Brazil
- Faculty of Medical Sciences, Laboratory of Cell Signaling, Obesity and Comorbidities Center - OCRC, University of Campinas, Campinas, Brazil
| | - Rodrigo S Carraro
- Faculty of Medical Sciences, Laboratory of Cell Signaling, Obesity and Comorbidities Center - OCRC, University of Campinas, Campinas, Brazil
- Faculty of Medical Sciences, University of Campinas, Campinas, Brazil
| | - Davi Sidarta-Oliveira
- Faculty of Medical Sciences, Laboratory of Cell Signaling, Obesity and Comorbidities Center - OCRC, University of Campinas, Campinas, Brazil
- Faculty of Medical Sciences, University of Campinas, Campinas, Brazil
| | - Guilherme R A de Mendonça
- Faculty of Medical Sciences, Laboratory of Cell Signaling, Obesity and Comorbidities Center - OCRC, University of Campinas, Campinas, Brazil
- Faculty of Medical Sciences, University of Campinas, Campinas, Brazil
| | - Licio A Velloso
- Faculty of Medical Sciences, Laboratory of Cell Signaling, Obesity and Comorbidities Center - OCRC, University of Campinas, Campinas, Brazil
- Faculty of Medical Sciences, University of Campinas, Campinas, Brazil
| | - Eliana P Araújo
- Nursing School, Laboratory of Cell Signaling Obesity and Comorbidities Center, OCRC, University of Campinas, Campinas, Brazil
- Faculty of Medical Sciences, Laboratory of Cell Signaling, Obesity and Comorbidities Center - OCRC, University of Campinas, Campinas, Brazil
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7
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Mao C, Xiao P, Tao XN, Qin J, He QT, Zhang C, Guo SC, Du YQ, Chen LN, Shen DD, Yang ZS, Zhang HQ, Huang SM, He YH, Cheng J, Zhong YN, Shang P, Chen J, Zhang DL, Wang QL, Liu MX, Li GY, Guo Y, Xu HE, Wang C, Zhang C, Feng S, Yu X, Zhang Y, Sun JP. Unsaturated bond recognition leads to biased signal in a fatty acid receptor. Science 2023; 380:eadd6220. [PMID: 36862765 DOI: 10.1126/science.add6220] [Citation(s) in RCA: 40] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 02/16/2023] [Indexed: 03/04/2023]
Abstract
Individual free fatty acids (FAs) play important roles in metabolic homeostasis, many through engagement with more than 40G protein-coupled receptors. Searching for receptors to sense beneficial omega-3 FAs of fish oil enabled the identification of GPR120, which is involved in a spectrum of metabolic diseases. Here, we report six cryo-electron microscopy structures of GPR120 in complex with FA hormones or TUG891 and Gi or Giq trimers. Aromatic residues inside the GPR120 ligand pocket were responsible for recognizing different double-bond positions of these FAs and connect ligand recognition to distinct effector coupling. We also investigated synthetic ligand selectivity and the structural basis of missense single-nucleotide polymorphisms. We reveal how GPR120 differentiates rigid double bonds and flexible single bonds. The knowledge gleaned here may facilitate rational drug design targeting to GPR120.
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Affiliation(s)
- Chunyou Mao
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Peng Xiao
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Xiao-Na Tao
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
- Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing 100191, China
- The Second Hospital of Shandong University, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Jiao Qin
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Qing-Tao He
- Department of Orthopedics, Qilu Hospital of Shandong University, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Chao Zhang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Sheng-Chao Guo
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Ya-Qin Du
- Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing 100191, China
| | - Li-Nan Chen
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Dan-Dan Shen
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Zhi-Shuai Yang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Han-Qiong Zhang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Shen-Ming Huang
- Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing 100191, China
| | - Yong-Hao He
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Jie Cheng
- Advanced Medical Research Institute, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
| | - Ya-Ni Zhong
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Pan Shang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
| | - Jun Chen
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Dao-Lai Zhang
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Qian-Lang Wang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Mei-Xia Liu
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Guo-Yu Li
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Yongyuan Guo
- Department of Orthopedics, Qilu Hospital of Shandong University, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - H Eric Xu
- CAS Key Laboratory of Receptor Research, Center for Structure and Function of Drug Targets, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Chuanxin Wang
- The Second Hospital of Shandong University, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Cheng Zhang
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, the State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, Jinan 250012, China
| | - Shiqing Feng
- The Second Hospital of Shandong University, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
- Department of Orthopedics, Qilu Hospital of Shandong University, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Xiao Yu
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
| | - Yan Zhang
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou 311121, China
- MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Medicine, Hangzhou 310058, China
- Research and Development Center for E-Learning, Ministry of Education, Beijing 100816, China
| | - Jin-Peng Sun
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
- Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing 100191, China
- Advanced Medical Research Institute, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
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8
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McKillop AM, Miskelly MG, Moran BM, Flatt PR. Incretins play an important role in FFA4/GPR120 regulation of glucose metabolism by GW-9508. Life Sci 2023; 318:121475. [PMID: 36754346 DOI: 10.1016/j.lfs.2023.121475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 01/30/2023] [Accepted: 02/02/2023] [Indexed: 02/10/2023]
Abstract
AIMS To assess the role of GPR120 in glucose metabolism and incretin regulation from enteroendocrine L- and K-cells with determination of the cellular localisation of GPR120 in intestinal tissue and clonal Glucagon-Like Peptide-1 (GLP-1)/Gastric Inhibitory Polypeptide (GIP) cell lines. MAIN METHODS Anti-hyperglycaemic, insulinotropic and incretin secreting properties of the GPR120 agonist, GW-9508 were explored in combination with oral and intraperitoneal glucose tolerance tests (GTT) in lean, diabetic and incretin receptor knockout mice. Cellular localisation of GPR120 was assessed by double immunofluorescence. KEY FINDINGS Compared to intraperitoneal injection, oral administration of GW-9508 (0.1 μmol/kg body weight) together with glucose reduced the glycaemic excursion by 22-31 % (p < 0.05-p < 0.01) and enhanced glucose-induced insulin release by 30 % (p < 0.01) in normal mice. In high fat fed diabetic mice, orally administered GW-9508 lowered plasma glucose by 17-27 % (p < 0.05-p < 0.01) and augmented insulin release by 22-39 % (p < 0.05-p < 0.001). GW-9508 had no effect on the responses of GLP-1 receptor knockout mice and GIP receptor knockout mice. Consistent with this, oral GW-9508 increased circulating total GLP-1 release by 39-44 % (p < 0.01) and total GIP by 37-47 % (p < 0.01-p < 0.001) after 15 and 30 min in lean NIH Swiss mice. Immunocytochemistry demonstrated GPR120 expression on mouse enteroendocrine L- and K-cells, GLUTag cells and pGIP/Neo STC-1 cells. SIGNIFICANCE GPR120 is expressed on intestinal L- and K-cells and stimulates GLP-1/GIP secretory pathways involved in mediating enhanced insulin secretion and improved glucose tolerance, following oral GW-9508. These novel data strongly support the development of potent and selective GPR120 agonists as an effective therapeutic approach for diabetes.
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Affiliation(s)
- Aine M McKillop
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine BT52 1SA, Northern Ireland, UK.
| | - Michael G Miskelly
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine BT52 1SA, Northern Ireland, UK
| | - Brian M Moran
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine BT52 1SA, Northern Ireland, UK
| | - Peter R Flatt
- School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine BT52 1SA, Northern Ireland, UK
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9
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Fu Q, Jiang H, Qian Y, Lv H, Dai H, Zhou Y, Chen Y, He Y, Gao R, Zheng S, Liang Y, Li S, Xu X, Xu K, Yang T. Single-cell RNA sequencing combined with single-cell proteomics identifies the metabolic adaptation of islet cell subpopulations to high-fat diet in mice. Diabetologia 2023; 66:724-740. [PMID: 36538064 PMCID: PMC9765371 DOI: 10.1007/s00125-022-05849-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Accepted: 10/13/2022] [Indexed: 12/24/2022]
Abstract
AIMS/HYPOTHESIS Islets have complex heterogeneity and subpopulations. Cell surface markers representing alpha, beta and delta cell subpopulations are urgently needed for investigations to explore the compositional changes of each subpopulation in obesity progress and diabetes onset, and the adaptation mechanism of islet metabolism induced by a high-fat diet (HFD). METHODS Single-cell RNA sequencing (scRNA-seq) was applied to identify alpha, beta and delta cell subpopulation markers in an HFD-induced mouse model of glucose intolerance. Flow cytometry and immunostaining were used to sort and assess the proportion of each subpopulation. Single-cell proteomics was performed on sorted cells, and the functional status of each alpha, beta and delta cell subpopulation in glucose intolerance was deeply elucidated based on protein expression. RESULTS A total of 33,999 cells were analysed by scRNA-seq and clustered into eight populations, including alpha, beta and delta cells. For alpha cells, scRNA-seq revealed that the Ace2low subpopulation had downregulated expression of genes related to alpha cell function and upregulated expression of genes associated with beta cell characteristics in comparison with the Ace2high subpopulation. The impaired function and increased fragility of ACE2low alpha cells exposure to HFD was further suggested by single-cell proteomics. As for beta cells, the CD81high subpopulation may indicate an immature signature of beta cells compared with the CD81low subpopulation, which had robust function. We also found differential expression of Slc2a2 in delta cells and a potentially stronger cellular function and metabolism in GLUT2low delta cells than GLUT2high delta cells. Moreover, an increased proportion of ACE2low alpha cells and CD81low beta cells, with a constant proportion of GLUT2low delta cells, were observed in HFD-induced glucose intolerance. CONCLUSIONS/INTERPRETATION We identified ACE2, CD81 and GLUT2 as surface markers to distinguish, respectively, alpha, beta and delta cell subpopulations with heterogeneous maturation and function. The changes in the proportion and functional status of islet endocrine subpopulations reflect the metabolic adaptation of islets to high-fat stress, which weakened the function of alpha cells and enhanced the function of beta and delta cells to bring about glycaemic homeostasis. Our findings provide a fundamental resource for exploring the mechanisms maintaining each islet endocrine subpopulation's fate and function in health and disease. DATA AVAILABILITY The scRNA-seq analysis datasets from the current study are available in the Gene Expression Omnibus (GEO) repository under the accession number GSE203376.
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Affiliation(s)
- Qi Fu
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Hemin Jiang
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yu Qian
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Hui Lv
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Hao Dai
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yuncai Zhou
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yang Chen
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yunqiang He
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Rui Gao
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Shuai Zheng
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yucheng Liang
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Siqi Li
- BGI-Shenzhen, Shenzhen, China
- BGI-Wuhan Clinical Laboratories, BGI-Shenzhen, Wuhan, China
| | - Xinyu Xu
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Kuanfeng Xu
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
| | - Tao Yang
- Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
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Samovski D, Jacome-Sosa M, Abumrad NA. Fatty Acid Transport and Signaling: Mechanisms and Physiological Implications. Annu Rev Physiol 2023; 85:317-337. [PMID: 36347219 DOI: 10.1146/annurev-physiol-032122-030352] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Long-chain fatty acids (FAs) are components of plasma membranes and an efficient fuel source and also serve as metabolic regulators through FA signaling mediated by membrane FA receptors. Impaired tissue FA uptake has been linked to major complications of obesity, including insulin resistance, cardiovascular disease, and type 2 diabetes. Fatty acid interactions with a membrane receptor and the initiation of signaling can modify pathways related to nutrient uptake and processing, cell proliferation or differentiation, and secretion of bioactive factors. Here, we review the major membrane receptors involved in FA uptake and FA signaling. We focus on two types of membrane receptors for long-chain FAs: CD36 and the G protein-coupled FA receptors FFAR1 and FFAR4. We describe key signaling pathways and metabolic outcomes for CD36, FFAR1, and FFAR4 and highlight the parallels that provide insight into FA regulation of cell function.
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Affiliation(s)
- Dmitri Samovski
- Center for Human Nutrition, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA;
| | - Miriam Jacome-Sosa
- Center for Human Nutrition, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA;
| | - Nada A Abumrad
- Center for Human Nutrition, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA; .,Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
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11
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How Arrestins and GRKs Regulate the Function of Long Chain Fatty Acid Receptors. Int J Mol Sci 2022; 23:ijms232012237. [PMID: 36293091 PMCID: PMC9602559 DOI: 10.3390/ijms232012237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 10/03/2022] [Accepted: 10/08/2022] [Indexed: 11/16/2022] Open
Abstract
FFA1 and FFA4, two G protein-coupled receptors that are activated by long chain fatty acids, play crucial roles in mediating many biological functions in the body. As a result, these fatty acid receptors have gained considerable attention due to their potential to be targeted for the treatment of type-2 diabetes. However, the relative contribution of canonical G protein-mediated signalling versus the effects of agonist-induced phosphorylation and interactions with β-arrestins have yet to be fully defined. Recently, several reports have highlighted the ability of β-arrestins and GRKs to interact with and modulate different functions of both FFA1 and FFA4, suggesting that it is indeed important to consider these interactions when studying the roles of FFA1 and FFA4 in both normal physiology and in different disease settings. Here, we discuss what is currently known and show the importance of understanding fully how β-arrestins and GRKs regulate the function of long chain fatty acid receptors.
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12
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Du YQ, Sha XY, Cheng J, Wang J, Lin JY, An WT, Pan W, Zhang LJ, Tao XN, Xu YF, Jia YL, Yang Z, Xiao P, Liu M, Sun JP, Yu X. Endogenous Lipid-GPR120 Signaling Modulates Pancreatic Islet Homeostasis to Different Extents. Diabetes 2022; 71:1454-1471. [PMID: 35472681 DOI: 10.2337/db21-0794] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 04/04/2022] [Indexed: 11/13/2022]
Abstract
Long-chain fatty acids (LCFAs) are not only energy sources but also serve as signaling molecules. GPR120, an LCFA receptor, plays key roles in maintaining metabolic homeostasis. However, whether endogenous ligand-GPR120 circuits exist and how such circuits function in pancreatic islets are unclear. Here, we found that endogenous GPR120 activity in pancreatic δ-cells modulated islet functions. At least two unsaturated LCFAs, oleic acid (OA) and linoleic acid (LA), were identified as GPR120 agonists within pancreatic islets. These two LCFAs promoted insulin secretion by inhibiting somatostatin secretion and showed bias activation of GPR120 in a model system. Compared with OA, LA exerted higher potency in promoting insulin secretion, which is dependent on β-arrestin2 function. Moreover, GPR120 signaling was impaired in the diabetic db/db model, and replenishing OA and LA improved islet function in both the db/db and streptozotocin-treated diabetic models. Consistently, the administration of LA improved glucose metabolism in db/db mice. Collectively, our results reveal that endogenous LCFA-GPR120 circuits exist and modulate homeostasis in pancreatic islets. The contributions of phenotype differences caused by different LCFA-GPR120 circuits within islets highlight the roles of fine-tuned ligand-receptor signaling networks in maintaining islet homeostasis.
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Affiliation(s)
- Ya-Qin Du
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing, China
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Xue-Ying Sha
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing, China
| | - Jie Cheng
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Jin Wang
- Department of Pharmacology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Jing-Yu Lin
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Wen-Tao An
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Wei Pan
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Li-Jun Zhang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Xiao-Na Tao
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Yun-Fei Xu
- Department of General Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Ying-Li Jia
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing, China
| | - Zhao Yang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Peng Xiao
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Ming Liu
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
- Division of Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, MI
| | - Jin-Peng Sun
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing, China
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Xiao Yu
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
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Morriseau TS, Doucette CA, Dolinsky VW. More than meets the islet: aligning nutrient and paracrine inputs with hormone secretion in health and disease. Am J Physiol Endocrinol Metab 2022; 322:E446-E463. [PMID: 35373587 DOI: 10.1152/ajpendo.00411.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The pancreatic islet is responsive to an array of endocrine, paracrine, and nutritional inputs that adjust hormone secretion to ensure accurate control of glucose homeostasis. Although the mechanisms governing glucose-coupled insulin secretion have received the most attention, there is emerging evidence for a multitude of physiological signaling pathways and paracrine networks that collectively regulate insulin, glucagon, and somatostatin release. Moreover, the modulation of these pathways in conditions of glucotoxicity or lipotoxicity are areas of both growing interest and controversy. In this review, the contributions of external, intrinsic, and paracrine factors in pancreatic β-, α-, and δ-cell secretion across the full spectrum of physiological (i.e., fasting and fed) and pathophysiological (gluco- and lipotoxicity; diabetes) environments will be critically discussed.
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Affiliation(s)
- Taylor S Morriseau
- Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme of the Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Christine A Doucette
- Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme of the Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
- Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Vernon W Dolinsky
- Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme of the Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, Manitoba, Canada
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14
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Murphy KA, Harsch BA, Healy CL, Joshi SS, Huang S, Walker RE, Wagner BM, Ernste KM, Huang W, Block RC, Wright CD, Tintle N, Jensen BC, Wells QS, Shearer GC, O’Connell TD. Free fatty acid receptor 4 responds to endogenous fatty acids to protect the heart from pressure overload. Cardiovasc Res 2022; 118:1061-1073. [PMID: 33752243 PMCID: PMC8930069 DOI: 10.1093/cvr/cvab111] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 03/19/2021] [Indexed: 12/19/2022] Open
Abstract
AIMS Free fatty acid receptor 4 (Ffar4) is a G-protein-coupled receptor for endogenous medium-/long-chain fatty acids that attenuates metabolic disease and inflammation. However, the function of Ffar4 in the heart is unclear. Given its putative beneficial role, we hypothesized that Ffar4 would protect the heart from pathologic stress. METHODS AND RESULTS In mice lacking Ffar4 (Ffar4KO), we found that Ffar4 is required for an adaptive response to pressure overload induced by transverse aortic constriction (TAC), identifying a novel cardioprotective function for Ffar4. Following TAC, remodelling was worsened in Ffar4KO hearts, with greater hypertrophy and contractile dysfunction. Transcriptome analysis 3-day post-TAC identified transcriptional deficits in genes associated with cytoplasmic phospholipase A2α signalling and oxylipin synthesis and the reduction of oxidative stress in Ffar4KO myocytes. In cultured adult cardiac myocytes, Ffar4 induced the production of the eicosapentaenoic acid (EPA)-derived, pro-resolving oxylipin 18-hydroxyeicosapentaenoic acid (18-HEPE). Furthermore, the activation of Ffar4 attenuated cardiac myocyte death from oxidative stress, while 18-HEPE rescued Ffar4KO myocytes. Systemically, Ffar4 maintained pro-resolving oxylipins and attenuated autoxidation basally, and increased pro-inflammatory and pro-resolving oxylipins, including 18-HEPE, in high-density lipoproteins post-TAC. In humans, Ffar4 expression decreased in heart failure, while the signalling-deficient Ffar4 R270H polymorphism correlated with eccentric remodelling in a large clinical cohort paralleling changes observed in Ffar4KO mice post-TAC. CONCLUSION Our data indicate that Ffar4 in cardiac myocytes responds to endogenous fatty acids, reducing oxidative injury, and protecting the heart from pathologic stress, with significant translational implications for targeting Ffar4 in cardiovascular disease.
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Affiliation(s)
- Katherine A Murphy
- Department of Integrative Biology and Physiology, University of Minnesota, 3-141 CCRB, 2231 6th Street SE, Minneapolis, MN 55414, USA
| | - Brian A Harsch
- Department of Nutritional Sciences, The Pennsylvania State University, 110 Chandlee Laboratory, University Park, PA 16802, USA
| | - Chastity L Healy
- Department of Integrative Biology and Physiology, University of Minnesota, 3-141 CCRB, 2231 6th Street SE, Minneapolis, MN 55414, USA
| | - Sonal S Joshi
- Department of Integrative Biology and Physiology, University of Minnesota, 3-141 CCRB, 2231 6th Street SE, Minneapolis, MN 55414, USA
| | - Shue Huang
- Department of Nutritional Sciences, The Pennsylvania State University, 110 Chandlee Laboratory, University Park, PA 16802, USA
| | - Rachel E Walker
- Department of Nutritional Sciences, The Pennsylvania State University, 110 Chandlee Laboratory, University Park, PA 16802, USA
| | - Brandon M Wagner
- Department of Integrative Biology and Physiology, University of Minnesota, 3-141 CCRB, 2231 6th Street SE, Minneapolis, MN 55414, USA
| | - Katherine M Ernste
- Department of Integrative Biology and Physiology, University of Minnesota, 3-141 CCRB, 2231 6th Street SE, Minneapolis, MN 55414, USA
| | - Wei Huang
- Division of Cardiology and McAllister Heart Institute, University of North Carolina, Chapel Hill, NC, USA
| | - Robert C Block
- Department of Public Health Sciences, University of Rochester, NY, USA
| | | | - Nathan Tintle
- Department of Statistics, Dordt University, Sioux Center, IA, USA
| | - Brian C Jensen
- Division of Cardiology and McAllister Heart Institute, University of North Carolina, Chapel Hill, NC, USA
| | - Quinn S Wells
- Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Gregory C Shearer
- Department of Nutritional Sciences, The Pennsylvania State University, 110 Chandlee Laboratory, University Park, PA 16802, USA
| | - Timothy D O’Connell
- Department of Integrative Biology and Physiology, University of Minnesota, 3-141 CCRB, 2231 6th Street SE, Minneapolis, MN 55414, USA
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15
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Nutrient Sensing via Gut in Drosophila melanogaster. Int J Mol Sci 2022; 23:ijms23052694. [PMID: 35269834 PMCID: PMC8910450 DOI: 10.3390/ijms23052694] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/20/2021] [Accepted: 12/20/2021] [Indexed: 01/08/2023] Open
Abstract
Nutrient-sensing mechanisms in animals' sense available nutrients to generate a physiological regulatory response involving absorption, digestion, and regulation of food intake and to maintain glucose and energy homeostasis. During nutrient sensing via the gastrointestinal tract, nutrients interact with receptors on the enteroendocrine cells in the gut, which in return respond by secreting various hormones. Sensing of nutrients by the gut plays a critical role in transmitting food-related signals to the brain and other tissues informing the composition of ingested food to digestive processes. These signals modulate feeding behaviors, food intake, metabolism, insulin secretion, and energy balance. The increasing significance of fly genetics with the availability of a vast toolbox for studying physiological function, expression of chemosensory receptors, and monitoring the gene expression in specific cells of the intestine makes the fly gut the most useful tissue for studying the nutrient-sensing mechanisms. In this review, we emphasize on the role of Drosophila gut in nutrient-sensing to maintain metabolic homeostasis and gut-brain cross talk using endocrine and neuronal signaling pathways stimulated by internal state or the consumption of various dietary nutrients. Overall, this review will be useful in understanding the post-ingestive nutrient-sensing mechanisms having a physiological and pathological impact on health and diseases.
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16
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Patti AM, Giglio RV, Papanas N, Serban D, Stoian AP, Pafili K, Al Rasadi K, Rajagopalan K, Rizvi AA, Ciaccio M, Rizzo M. Experimental and Emerging Free Fatty Acid Receptor Agonists for the Treatment of Type 2 Diabetes. MEDICINA (KAUNAS, LITHUANIA) 2022; 58:medicina58010109. [PMID: 35056417 PMCID: PMC8779029 DOI: 10.3390/medicina58010109] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 01/08/2022] [Accepted: 01/10/2022] [Indexed: 04/11/2023]
Abstract
The current management of Type 2 Diabetes Mellitus (T2DM) includes incretin-based treatments able to enhance insulin secretion and peripheral insulin sensitivity as well as improve body mass, inflammation, plasma lipids, blood pressure, and cardiovascular outcomes. Dietary Free Fatty Acids (FFA) regulate metabolic and anti-inflammatory processes through their action on incretins. Selective synthetic ligands for FFA1-4 receptors have been developed as potential treatments for T2DM. To comprehensively review the available evidence for the potential role of FFA receptor agonists in the treatment of T2DM, we performed an electronic database search assessing the association between FFAs, T2DM, inflammation, and incretins. Evidence indicates that FFA1-4 agonism increases insulin sensitivity, induces body mass loss, reduces inflammation, and has beneficial metabolic effects. There is a strong inter-relationship between FFAs and incretins. FFA receptor agonism represents a potential target for the treatment of T2DM and may provide an avenue for the management of cardiometabolic risk in susceptible individuals. Further research promises to shed more light on this emerging topic.
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Affiliation(s)
- Angelo Maria Patti
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties, School of Medicine, University of Palermo, 90133 Palermo, Italy; (A.M.P.); (M.R.)
| | - Rosaria Vincenza Giglio
- Department of Biomedicine, Neuroscience, and Advanced Diagnostics, Institute of Clinical Biochemistry, Clinical Molecular Medicine and Laboratory Medicine, University of Palermo, 90127 Palermo, Italy; (R.V.G.); (M.C.)
| | - Nikolaos Papanas
- Diabetes Centre, Second Department of Internal Medicine, Democritus University of Thrace, 68132 Alexandroupolis, Greece; (N.P.); (K.P.)
| | - Dragos Serban
- Forth Surgery Department, Faculty of Medicine, Carol Davila University, 050098 Bucharest, Romania;
| | - Anca Pantea Stoian
- Department of Diabetes, Faculty of Medicine, Nutrition and Metabolic Diseases, Carol Davila University, 050474 Bucharest, Romania;
| | - Kalliopi Pafili
- Diabetes Centre, Second Department of Internal Medicine, Democritus University of Thrace, 68132 Alexandroupolis, Greece; (N.P.); (K.P.)
| | - Khalid Al Rasadi
- Medical Research Center, Sultan Qaboos University, Muscat 123, Oman;
| | - Kanya Rajagopalan
- Department of Medicine, University of Central Florida College of Medicine, Orlando, FL 32827, USA;
| | - Ali A. Rizvi
- Department of Medicine, University of Central Florida College of Medicine, Orlando, FL 32827, USA;
- Division of Endocrinology, Diabetes and Metabolism, University of South Carolina School of Medicine, Columbia, SC 29208, USA
- Correspondence:
| | - Marcello Ciaccio
- Department of Biomedicine, Neuroscience, and Advanced Diagnostics, Institute of Clinical Biochemistry, Clinical Molecular Medicine and Laboratory Medicine, University of Palermo, 90127 Palermo, Italy; (R.V.G.); (M.C.)
- Department of Laboratory Medicine, University Hospital, 90127 Palermo, Italy
| | - Manfredi Rizzo
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties, School of Medicine, University of Palermo, 90133 Palermo, Italy; (A.M.P.); (M.R.)
- Department of Diabetes, Faculty of Medicine, Nutrition and Metabolic Diseases, Carol Davila University, 050474 Bucharest, Romania;
- Division of Endocrinology, Diabetes and Metabolism, University of South Carolina School of Medicine, Columbia, SC 29208, USA
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17
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Zhao YF. Free fatty acid receptors in the endocrine regulation of glucose metabolism: Insight from gastrointestinal-pancreatic-adipose interactions. Front Endocrinol (Lausanne) 2022; 13:956277. [PMID: 36246919 PMCID: PMC9554507 DOI: 10.3389/fendo.2022.956277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 09/14/2022] [Indexed: 11/25/2022] Open
Abstract
Glucose metabolism is primarily controlled by pancreatic hormones, with the coordinated assistance of the hormones from gastrointestine and adipose tissue. Studies have unfolded a sophisticated hormonal gastrointestinal-pancreatic-adipose interaction network, which essentially maintains glucose homeostasis in response to the changes in substrates and nutrients. Free fatty acids (FFAs) are the important substrates that are involved in glucose metabolism. FFAs are able to activate the G-protein coupled membrane receptors including GPR40, GPR120, GPR41 and GPR43, which are specifically expressed in pancreatic islet cells, enteroendocrine cells as well as adipocytes. The activation of FFA receptors regulates the secretion of hormones from pancreas, gastrointestine and adipose tissue to influence glucose metabolism. This review presents the effects of the FFA receptors on glucose metabolism via the hormonal gastrointestinal-pancreatic-adipose interactions and the underlying intracellular mechanisms. Furthermore, the development of therapeutic drugs targeting FFA receptors for the treatment of abnormal glucose metabolism such as type 2 diabetes mellitus is summarized.
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18
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Miranda C, Begum M, Vergari E, Briant LJB. Gap junction coupling and islet delta-cell function in health and disease. Peptides 2022; 147:170704. [PMID: 34826505 DOI: 10.1016/j.peptides.2021.170704] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 11/12/2021] [Accepted: 11/19/2021] [Indexed: 12/12/2022]
Abstract
The pancreatic islets contain beta-cells and alpha-cells, which are responsible for secreting two principal gluco-regulatory hormones; insulin and glucagon, respectively. However, they also contain delta-cells, a relatively sparse cell type that secretes somatostatin (SST). These cells have a complex morphology allowing them to establish an extensive communication network throughout the islet, despite their scarcity. Delta-cells are electrically excitable cells, and SST secretion is released in a glucose- and KATP-dependent manner. SST hyperpolarises the alpha-cell membrane and suppresses exocytosis. In this way, islet SST potently inhibits glucagon release. Recent studies investigating the activity of delta-cells have revealed they are electrically coupled to beta-cells via gap junctions, suggesting the delta-cell is more than just a paracrine inhibitor. In this Review, we summarize delta-cell morphology, function, and the role of SST signalling for regulating islet hormonal output. A distinguishing feature of this Review is that we attempt to use the discovery of this gap junction pathway, together with what is already known about delta-cells, to reframe the role of these cells in both health and disease. In particular, we argue that the discovery of gap junction communication between delta-cells and beta-cells provides new insights into the contribution of delta-cells to the islet hormonal defects observed in both type 1 and type 2 diabetes. This reappraisal of the delta-cell is important as it may offer novel insights into how the physiology of this cell can be utilised to restore islet function in diabetes.
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Affiliation(s)
- Caroline Miranda
- Institute of Neuroscience and Physiology, Metabolic Research Unit, University of Göteborg, 405 30, Göteborg, Sweden
| | - Manisha Begum
- Institute of Neuroscience and Physiology, Metabolic Research Unit, University of Göteborg, 405 30, Göteborg, Sweden; University of Skӧvde, Department of Infection Biology, Högskolevägen 1, 541 28, Skövde, Sweden
| | - Elisa Vergari
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, OX4 7LE, Oxford, UK
| | - Linford J B Briant
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, OX4 7LE, Oxford, UK; Department of Computer Science, University of Oxford, OX1 3QD, Oxford, UK.
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19
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Cho JH, Hughes JW. Cilia Action in Islets: Lessons From Mouse Models. Front Endocrinol (Lausanne) 2022; 13:922983. [PMID: 35813631 PMCID: PMC9260721 DOI: 10.3389/fendo.2022.922983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 05/23/2022] [Indexed: 11/30/2022] Open
Abstract
Primary cilia as a signaling organelle have garnered recent attention as a regulator of pancreatic islet function. These rod-like sensors exist on all major islet endocrine cell types and transduce a variety of external cues, while dysregulation of cilia function contributes to the development of diabetes. The complex role of islet primary cilia has been examined using genetic deletion targeting various components of cilia. In this review, we summarize experimental models for the study of islet cilia and current understanding of mechanisms of cilia regulation of islet hormone secretion. Consensus from these studies shows that pancreatic cilia perturbation can cause both endocrine and exocrine defects that are relevant to human disease. We discuss future research directions that would further elucidate cilia action in distinct groups of islet cells, including paracrine and juxtacrine regulation, GPCR signaling, and endocrine-exocrine crosstalk.
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20
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Yau B, Naghiloo S, Diaz-Vegas A, Carr AV, Van Gerwen J, Needham EJ, Jevon D, Chen SY, Hoehn KL, Brandon AE, Macia L, Cooney GJ, Shortreed MR, Smith LM, Keller MP, Thorn P, Larance M, James DE, Humphrey SJ, Kebede MA. Proteomic pathways to metabolic disease and type 2 diabetes in the pancreatic islet. iScience 2021; 24:103099. [PMID: 34622154 PMCID: PMC8479695 DOI: 10.1016/j.isci.2021.103099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 08/09/2021] [Accepted: 09/06/2021] [Indexed: 12/13/2022] Open
Abstract
Pancreatic islets are essential for maintaining physiological blood glucose levels, and declining islet function is a hallmark of type 2 diabetes. We employ mass spectrometry-based proteomics to systematically analyze islets from 9 genetic or diet-induced mouse models representing a broad cross-section of metabolic health. Quantifying the islet proteome to a depth of >11,500 proteins, this study represents the most detailed analysis of mouse islet proteins to date. Our data highlight that the majority of islet proteins are expressed in all strains and diets, but more than half of the proteins vary in expression levels, principally due to genetics. Associating these varied protein expression levels on an individual animal basis with individual phenotypic measures reveals islet mitochondrial function as a major positive indicator of metabolic health regardless of strain. This compendium of strain-specific and dietary changes to mouse islet proteomes represents a comprehensive resource for basic and translational islet cell biology.
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Affiliation(s)
- Belinda Yau
- Discipline of Physiology, School of Medical Sciences, Charles Perkins Centre, University of Sydney, Camperdown 2006, Australia
| | - Sheyda Naghiloo
- Discipline of Physiology, School of Medical Sciences, Charles Perkins Centre, University of Sydney, Camperdown 2006, Australia
| | - Alexis Diaz-Vegas
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - Austin V. Carr
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Julian Van Gerwen
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - Elise J. Needham
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - Dillon Jevon
- Discipline of Physiology, School of Medical Sciences, Charles Perkins Centre, University of Sydney, Camperdown 2006, Australia
| | - Sing-Young Chen
- Department of Biotechnology and Biomolecular Sciences, University of New South Wales, Kensington, NSW 2052, Australia
| | - Kyle L. Hoehn
- Department of Biotechnology and Biomolecular Sciences, University of New South Wales, Kensington, NSW 2052, Australia
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA
| | - Amanda E. Brandon
- Discipline of Physiology, School of Medical Sciences, Charles Perkins Centre, University of Sydney, Camperdown 2006, Australia
| | - Laurance Macia
- Discipline of Physiology, School of Medical Sciences, Charles Perkins Centre, University of Sydney, Camperdown 2006, Australia
| | - Gregory J. Cooney
- Discipline of Physiology, School of Medical Sciences, Charles Perkins Centre, University of Sydney, Camperdown 2006, Australia
| | | | - Lloyd M. Smith
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Mark P. Keller
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Peter Thorn
- Discipline of Physiology, School of Medical Sciences, Charles Perkins Centre, University of Sydney, Camperdown 2006, Australia
| | - Mark Larance
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - David E. James
- Discipline of Physiology, School of Medical Sciences, Charles Perkins Centre, University of Sydney, Camperdown 2006, Australia
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - Sean J. Humphrey
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - Melkam A. Kebede
- Discipline of Physiology, School of Medical Sciences, Charles Perkins Centre, University of Sydney, Camperdown 2006, Australia
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21
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Abstract
Free fatty acids (FFAs) are implicated in the pathogenesis of metabolic diseases that includes obesity, type 2 diabetes mellitus, and cardiovascular disease (CVD). FFAs serve as ligands for free fatty acid receptors (FFARs) that belong to the family of rhodopsin-like G protein-coupled receptors (GPCRs) and are expressed throughout the body to maintain energy homeostasis under changing nutritional conditions. Free fatty acid receptor 4 (FFAR4), also known as G protein-coupled receptor 120, is a long-chain fatty acid receptor highly expressed in adipocytes, endothelial cells, and macrophages. Activation of FFAR4 helps maintain metabolic homeostasis by regulating adipogenesis, insulin sensitivity, and inflammation. Furthermore, dysfunction of FFAR4 is associated with insulin resistance, obesity, and eccentric remodeling in both humans and mice, making FFAR4 an attractive therapeutic target for treating or preventing metabolic diseases. While much of the previous literature on FFAR4 has focused on its role in obesity and diabetes, recent studies have demonstrated that FFAR4 may also play an important role in the development of atherosclerosis and CVD. Most notably, FFAR4 activation reduces monocyte-endothelial cell interaction, enhances cholesterol efflux from macrophages, reduces lesion size in atherogenic mouse models, and stimulates oxylipin production in myocytes that functions in a feed-forward cardioprotective mechanism. This review will focus on the role of FFAR4 in metabolic diseases and highlights an underappreciated role of FFAR4 in the development of atherosclerosis and CVD.
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Affiliation(s)
- Gage M Stuttgen
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Daisy Sahoo
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Department of Medicine, Division of Endocrinology & Molecular Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA
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22
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Hidalgo MA, Carretta MD, Burgos RA. Long Chain Fatty Acids as Modulators of Immune Cells Function: Contribution of FFA1 and FFA4 Receptors. Front Physiol 2021; 12:668330. [PMID: 34276398 PMCID: PMC8280355 DOI: 10.3389/fphys.2021.668330] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 06/04/2021] [Indexed: 12/13/2022] Open
Abstract
Long-chain fatty acids are molecules that act as metabolic intermediates and constituents of membranes; however, their novel role as signaling molecules in immune function has also been demonstrated. The presence of free fatty acid (FFA) receptors on immune cells has contributed to the understanding of this new role of long-chain fatty acids (LCFAs) in immune function, showing their role as anti-inflammatory or pro-inflammatory molecules and elucidating their intracellular mechanisms. The FFA1 and FFA4 receptors, also known as GPR40 and GPR120, respectively, have been described in macrophages and neutrophils, two key cells mediating innate immune response. Ligands of the FFA1 and FFA4 receptors induce the release of a myriad of cytokines through well-defined intracellular signaling pathways. In this review, we discuss the cellular responses and intracellular mechanisms activated by LCFAs, such as oleic acid, linoleic acid, palmitic acid, docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA), in T-cells, macrophages, and neutrophils, as well as the role of the FFA1 and FFA4 receptors in immune cells.
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Affiliation(s)
- Maria A Hidalgo
- Laboratory of Inflammation Pharmacology, Institute of Pharmacology and Morphophysiology, Universidad Austral de Chile, Valdivia, Chile
| | - Maria D Carretta
- Laboratory of Inflammation Pharmacology, Institute of Pharmacology and Morphophysiology, Universidad Austral de Chile, Valdivia, Chile
| | - Rafael A Burgos
- Laboratory of Inflammation Pharmacology, Institute of Pharmacology and Morphophysiology, Universidad Austral de Chile, Valdivia, Chile
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23
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Prihandoko R, Kaur D, Wiegman CH, Alvarez-Curto E, Donovan C, Chachi L, Ulven T, Tyas MR, Euston E, Dong Z, Alharbi AGM, Kim RY, Lowe JG, Hansbro PM, Chung KF, Brightling CE, Milligan G, Tobin AB. Pathophysiological regulation of lung function by the free fatty acid receptor FFA4. Sci Transl Med 2021; 12:12/557/eaaw9009. [PMID: 32817367 DOI: 10.1126/scitranslmed.aaw9009] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 10/22/2019] [Accepted: 07/28/2020] [Indexed: 12/31/2022]
Abstract
Increased prevalence of inflammatory airway diseases including asthma and chronic obstructive pulmonary disease (COPD) together with inadequate disease control by current frontline treatments means that there is a need to define therapeutic targets for these conditions. Here, we investigate a member of the G protein-coupled receptor family, FFA4, that responds to free circulating fatty acids including dietary omega-3 fatty acids found in fish oils. We show that FFA4, although usually associated with metabolic responses linked with food intake, is expressed in the lung where it is coupled to Gq/11 signaling. Activation of FFA4 by drug-like agonists produced relaxation of murine airway smooth muscle mediated at least in part by the release of the prostaglandin E2 (PGE2) that subsequently acts on EP2 prostanoid receptors. In normal mice, activation of FFA4 resulted in a decrease in lung resistance. In acute and chronic ozone models of pollution-mediated inflammation and house dust mite and cigarette smoke-induced inflammatory disease, FFA4 agonists acted to reduce airway resistance, a response that was absent in mice lacking expression of FFA4. The expression profile of FFA4 in human lung was similar to that observed in mice, and the response to FFA4/FFA1 agonists similarly mediated human airway smooth muscle relaxation ex vivo. Our study provides evidence that pharmacological targeting of lung FFA4, and possibly combined activation of FFA4 and FFA1, has in vivo efficacy and might have therapeutic value in the treatment of bronchoconstriction associated with inflammatory airway diseases such as asthma and COPD.
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Affiliation(s)
- Rudi Prihandoko
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, UK
| | - Davinder Kaur
- Institute for Lung Health, Leicester NIHR Biomedical Research Centre, University of Leicester, LE3 9QP, Leicester, UK
| | - Coen H Wiegman
- Airway Disease Section, National Heart and Lung Institute, Imperial College London, London SW3 6LY, UK
| | - Elisa Alvarez-Curto
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, UK
| | - Chantal Donovan
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute, New Lambton, NSW 2305 and The University of Newcastle, Callaghan, NSW 2208, Australia.,Centre for Inflammation, Centenary Institute, Sydney, NSW 2050, and University of Technology Sydney, Faculty of Science, Ultimo NSW 2007, Australia
| | - Latifa Chachi
- Institute for Lung Health, Leicester NIHR Biomedical Research Centre, University of Leicester, LE3 9QP, Leicester, UK
| | - Trond Ulven
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Martha R Tyas
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, UK
| | - Eloise Euston
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, UK
| | - Zhaoyang Dong
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, UK
| | - Abdulrahman Ghali M Alharbi
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, UK.,Department of Pharmacology and Toxicology, College of Pharmacy, Taibah University, Madinah 42353, Saudi Arabia
| | - Richard Y Kim
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute, New Lambton, NSW 2305 and The University of Newcastle, Callaghan, NSW 2208, Australia.,Centre for Inflammation, Centenary Institute, Sydney, NSW 2050, and University of Technology Sydney, Faculty of Science, Ultimo NSW 2007, Australia
| | - Jack G Lowe
- Airway Disease Section, National Heart and Lung Institute, Imperial College London, London SW3 6LY, UK
| | - Philip M Hansbro
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute, New Lambton, NSW 2305 and The University of Newcastle, Callaghan, NSW 2208, Australia.,Centre for Inflammation, Centenary Institute, Sydney, NSW 2050, and University of Technology Sydney, Faculty of Science, Ultimo NSW 2007, Australia
| | - Kian Fan Chung
- Airway Disease Section, National Heart and Lung Institute, Imperial College London, London SW3 6LY, UK
| | - Christopher E Brightling
- Institute for Lung Health, Leicester NIHR Biomedical Research Centre, University of Leicester, LE3 9QP, Leicester, UK.
| | - Graeme Milligan
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, UK.
| | - Andrew B Tobin
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow Glasgow, G12 8QQ, Scotland, UK.
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24
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Barella LF, Jain S, Kimura T, Pydi SP. Metabolic roles of G protein-coupled receptor signaling in obesity and type 2 diabetes. FEBS J 2021; 288:2622-2644. [PMID: 33682344 DOI: 10.1111/febs.15800] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 01/31/2021] [Accepted: 03/03/2021] [Indexed: 12/12/2022]
Abstract
The incidence of obesity and type 2 diabetes (T2D) has been increasing steadily worldwide. It is estimated that by 2045 more than 800 million people will be suffering from diabetes. Despite the advancements in modern medicine, more effective therapies for treating obesity and T2D are needed. G protein-coupled receptors (GPCRs) have emerged as important drug targets for various chronic diseases, including obesity, T2D, and liver diseases. During the past two decades, many laboratories worldwide focused on understanding the role of GPCR signaling in regulating glucose metabolism and energy homeostasis. The information gained from these studies can guide the development of novel therapeutic agents. In this review, we summarize recent studies providing insights into the role of GPCR signaling in peripheral, metabolically important tissues such as pancreas, liver, skeletal muscle, and adipose tissue, focusing primarily on the use of mutant animal models and human data.
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Affiliation(s)
- Luiz F Barella
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA.,Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Shanu Jain
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Takefumi Kimura
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Sai P Pydi
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA.,Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India
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25
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Lu VB, Gribble FM, Reimann F. Nutrient-Induced Cellular Mechanisms of Gut Hormone Secretion. Nutrients 2021; 13:nu13030883. [PMID: 33803183 PMCID: PMC8000029 DOI: 10.3390/nu13030883] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/27/2021] [Accepted: 03/05/2021] [Indexed: 02/06/2023] Open
Abstract
The gastrointestinal tract can assess the nutrient composition of ingested food. The nutrient-sensing mechanisms in specialised epithelial cells lining the gastrointestinal tract, the enteroendocrine cells, trigger the release of gut hormones that provide important local and central feedback signals to regulate nutrient utilisation and feeding behaviour. The evidence for nutrient-stimulated secretion of two of the most studied gut hormones, glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), along with the known cellular mechanisms in enteroendocrine cells recruited by nutrients, will be the focus of this review. The mechanisms involved range from electrogenic transporters, ion channel modulation and nutrient-activated G-protein coupled receptors that converge on the release machinery controlling hormone secretion. Elucidation of these mechanisms will provide much needed insight into postprandial physiology and identify tractable dietary approaches to potentially manage nutrition and satiety by altering the secreted gut hormone profile.
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26
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Ghislain J, Poitout V. Targeting lipid GPCRs to treat type 2 diabetes mellitus - progress and challenges. Nat Rev Endocrinol 2021; 17:162-175. [PMID: 33495605 DOI: 10.1038/s41574-020-00459-w] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/04/2020] [Indexed: 02/07/2023]
Abstract
Therapeutic approaches to the treatment of type 2 diabetes mellitus that are designed to increase insulin secretion either directly target β-cells or indirectly target gastrointestinal enteroendocrine cells (EECs), which release hormones that modulate insulin secretion (for example, incretins). Given that β-cells and EECs both express a large array of G protein-coupled receptors (GPCRs) that modulate insulin secretion, considerable research and development efforts have been undertaken to design therapeutic drugs targeting these GPCRs. Among them are GPCRs specific for free fatty acid ligands (lipid GPCRs), including free fatty acid receptor 1 (FFA1, otherwise known as GPR40), FFA2 (GPR43), FFA3 (GPR41) and FFA4 (GPR120), as well as the lipid metabolite binding glucose-dependent insulinotropic receptor (GPR119). These lipid GPCRs have demonstrated important roles in the control of islet and gut hormone secretion. Advances in lipid GPCR pharmacology have led to the identification of a number of synthetic agonists that exert beneficial effects on glucose homeostasis in preclinical studies. Yet, translation of these promising results to the clinic has so far been disappointing. In this Review, we present the physiological roles, pharmacology and clinical studies of these lipid receptors and discuss the challenges associated with their clinical development for the treatment of type 2 diabetes mellitus.
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Affiliation(s)
- Julien Ghislain
- Montreal Diabetes Research Center, Centre Hospitalier de l'Université de Montréal, Montréal, QC, Canada
| | - Vincent Poitout
- Montreal Diabetes Research Center, Centre Hospitalier de l'Université de Montréal, Montréal, QC, Canada.
- Department of Medicine, Université de Montréal, Montréal, QC, Canada.
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27
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Croze ML, Guillaume A, Ethier M, Fergusson G, Tremblay C, Campbell SA, Maachi H, Ghislain J, Poitout V. Combined Deletion of Free Fatty-Acid Receptors 1 and 4 Minimally Impacts Glucose Homeostasis in Mice. Endocrinology 2021; 162:6128704. [PMID: 33543237 DOI: 10.1210/endocr/bqab002] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Indexed: 12/16/2022]
Abstract
The free fatty-acid receptors FFAR1 (GPR40) and FFAR4 (GPR120) are implicated in the regulation of insulin secretion and insulin sensitivity, respectively. Although GPR120 and GPR40 share similar ligands, few studies have addressed possible interactions between these 2 receptors in the control of glucose homeostasis. Here we generated mice deficient in gpr120 (Gpr120KO) or gpr40 (Gpr40KO), alone or in combination (Gpr120/40KO), and metabolically phenotyped male and female mice fed a normal chow or high-fat diet. We assessed insulin secretion in isolated mouse islets exposed to selective GPR120 and GPR40 agonists singly or in combination. Following normal chow feeding, body weight and energy intake were unaffected by deletion of either receptor, although fat mass increased in Gpr120KO females. Fasting blood glucose levels were mildly increased in Gpr120/40KO mice and in a sex-dependent manner in Gpr120KO and Gpr40KO animals. Oral glucose tolerance was slightly reduced in male Gpr120/40KO mice and in Gpr120KO females, whereas insulin secretion and insulin sensitivity were unaffected. In hyperglycemic clamps, the glucose infusion rate was lower in male Gpr120/40KO mice, but insulin and c-peptide levels were unaffected. No changes in glucose tolerance were observed in either single or double knock-out animals under high-fat feeding. In isolated islets from wild-type mice, the combination of selective GPR120 and GPR40 agonists additively increased insulin secretion. We conclude that while simultaneous activation of GPR120 and GPR40 enhances insulin secretion ex vivo, combined deletion of these 2 receptors only minimally affects glucose homeostasis in vivo in mice.
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Affiliation(s)
- Marine L Croze
- Montreal Diabetes Research Center, CRCHUM, Montréal, QC, Canada
| | | | - Mélanie Ethier
- Montreal Diabetes Research Center, CRCHUM, Montréal, QC, Canada
| | - Grace Fergusson
- Montreal Diabetes Research Center, CRCHUM, Montréal, QC, Canada
| | | | | | - Hasna Maachi
- Montreal Diabetes Research Center, CRCHUM, Montréal, QC, Canada
| | - Julien Ghislain
- Montreal Diabetes Research Center, CRCHUM, Montréal, QC, Canada
| | - Vincent Poitout
- Montreal Diabetes Research Center, CRCHUM, Montréal, QC, Canada
- Department of Medicine, Université de Montréal, Montréal, QC, Canada
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28
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Croze ML, Flisher MF, Guillaume A, Tremblay C, Noguchi GM, Granziera S, Vivot K, Castillo VC, Campbell SA, Ghislain J, Huising MO, Poitout V. Free fatty acid receptor 4 inhibitory signaling in delta cells regulates islet hormone secretion in mice. Mol Metab 2021; 45:101166. [PMID: 33484949 PMCID: PMC7873385 DOI: 10.1016/j.molmet.2021.101166] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 01/08/2021] [Accepted: 01/11/2021] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE Maintenance of glucose homeostasis requires the precise regulation of hormone secretion from the endocrine pancreas. Free fatty acid receptor 4 (FFAR4/GPR120) is a G protein-coupled receptor whose activation in islets of Langerhans promotes insulin and glucagon secretion and inhibits somatostatin secretion. However, the contribution of individual islet cell types (α, β, and δ cells) to the insulinotropic and glucagonotropic effects of GPR120 remains unclear. As gpr120 mRNA is enriched in somatostatin-secreting δ cells, we hypothesized that GPR120 activation stimulates insulin and glucagon secretion via inhibition of somatostatin release. METHODS Glucose tolerance tests were performed in mice after administration of selective GPR120 agonist Compound A. Insulin, glucagon, and somatostatin secretion were measured in static incubations of isolated mouse islets in response to endogenous (ω-3 polyunsaturated fatty acids) and/or pharmacological (Compound A and AZ-13581837) GPR120 agonists. The effect of Compound A on hormone secretion was tested further in islets isolated from mice with global or somatostatin cell-specific knock-out of gpr120. Gpr120 expression was assessed in pancreatic sections by RNA in situ hybridization. Cyclic AMP (cAMP) and calcium dynamics in response to pharmacological GPR120 agonists were measured specifically in α, β, and δ cells in intact islets using cAMPER and GCaMP6 reporter mice, respectively. RESULTS Acute exposure to Compound A increased glucose tolerance, circulating insulin, and glucagon levels in vivo. Endogenous and/or pharmacological GPR120 agonists reduced somatostatin secretion in isolated islets and concomitantly demonstrated dose-dependent potentiation of glucose-stimulated insulin secretion and arginine-stimulated glucagon secretion. Gpr120 was enriched in δ cells. Pharmacological GPR120 agonists reduced cAMP and calcium levels in δ cells but increased these signals in α and β cells. Compound A-mediated inhibition of somatostatin secretion was insensitive to pertussis toxin. The effect of Compound A on hormone secretion was completely absent in islets from mice with either global or somatostatin cell-specific deletion of gpr120 and partially reduced upon blockade of somatostatin receptor signaling by cyclosomatostatin. CONCLUSIONS Inhibitory GPR120 signaling in δ cells contributes to both insulin and glucagon secretion in part by mitigating somatostatin release.
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Affiliation(s)
- Marine L Croze
- Montreal Diabetes Research Center, CRCHUM, Montréal, QC, Canada
| | - Marcus F Flisher
- Department of Neurobiology, Physiology, and Behavior, College of Biological Sciences, University of California Davis, Davis, CA, USA
| | | | | | - Glyn M Noguchi
- Department of Neurobiology, Physiology, and Behavior, College of Biological Sciences, University of California Davis, Davis, CA, USA
| | | | - Kevin Vivot
- Montreal Diabetes Research Center, CRCHUM, Montréal, QC, Canada
| | - Vincent C Castillo
- Department of Neurobiology, Physiology, and Behavior, College of Biological Sciences, University of California Davis, Davis, CA, USA
| | | | - Julien Ghislain
- Montreal Diabetes Research Center, CRCHUM, Montréal, QC, Canada
| | - Mark O Huising
- Department of Neurobiology, Physiology, and Behavior, College of Biological Sciences, University of California Davis, Davis, CA, USA; Department of Physiology and Membrane Biology, School of Medicine, University of California Davis, Davis, CA, USA
| | - Vincent Poitout
- Montreal Diabetes Research Center, CRCHUM, Montréal, QC, Canada; Department of Medicine, Université de Montréal, Montréal, QC, Canada.
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29
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Grundmann M, Bender E, Schamberger J, Eitner F. Pharmacology of Free Fatty Acid Receptors and Their Allosteric Modulators. Int J Mol Sci 2021; 22:ijms22041763. [PMID: 33578942 PMCID: PMC7916689 DOI: 10.3390/ijms22041763] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/04/2021] [Accepted: 02/06/2021] [Indexed: 12/19/2022] Open
Abstract
The physiological function of free fatty acids (FFAs) has long been regarded as indirect in terms of their activities as educts and products in metabolic pathways. The observation that FFAs can also act as signaling molecules at FFA receptors (FFARs), a family of G protein-coupled receptors (GPCRs), has changed the understanding of the interplay of metabolites and host responses. Free fatty acids of different chain lengths and saturation statuses activate FFARs as endogenous agonists via binding at the orthosteric receptor site. After FFAR deorphanization, researchers from the pharmaceutical industry as well as academia have identified several ligands targeting allosteric sites of FFARs with the aim of developing drugs to treat various diseases such as metabolic, (auto)inflammatory, infectious, endocrinological, cardiovascular, and renal disorders. GPCRs are the largest group of transmembrane proteins and constitute the most successful drug targets in medical history. To leverage the rich biology of this target class, the drug industry seeks alternative approaches to address GPCR signaling. Allosteric GPCR ligands are recognized as attractive modalities because of their auspicious pharmacological profiles compared to orthosteric ligands. While the majority of marketed GPCR drugs interact exclusively with the orthosteric binding site, allosteric mechanisms in GPCR biology stay medically underexploited, with only several allosteric ligands currently approved. This review summarizes the current knowledge on the biology of FFAR1 (GPR40), FFAR2 (GPR43), FFAR3 (GPR41), FFAR4 (GPR120), and GPR84, including structural aspects of FFAR1, and discusses the molecular pharmacology of FFAR allosteric ligands as well as the opportunities and challenges in research from the perspective of drug discovery.
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Affiliation(s)
- Manuel Grundmann
- Research and Early Development, Bayer Pharmaceuticals, Bayer AG, 42096 Wuppertal, Germany;
- Correspondence:
| | - Eckhard Bender
- Drug Discovery Sciences, Bayer Pharmaceuticals, Bayer AG, 42096 Wuppertal, Germany; (E.B.); (J.S.)
| | - Jens Schamberger
- Drug Discovery Sciences, Bayer Pharmaceuticals, Bayer AG, 42096 Wuppertal, Germany; (E.B.); (J.S.)
| | - Frank Eitner
- Research and Early Development, Bayer Pharmaceuticals, Bayer AG, 42096 Wuppertal, Germany;
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Gao R, Yang T, Zhang Q. δ-Cells: The Neighborhood Watch in the Islet Community. BIOLOGY 2021; 10:biology10020074. [PMID: 33494193 PMCID: PMC7909827 DOI: 10.3390/biology10020074] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/19/2021] [Accepted: 01/19/2021] [Indexed: 12/29/2022]
Abstract
Somatostatin-secreting δ-cells have aroused great attention due to their powerful roles in coordination of islet insulin and glucagon secretion and maintenance of glucose homeostasis. δ-cells exhibit neuron-like morphology with projections which enable pan-islet somatostatin paracrine regulation despite their scarcity in the islets. The expression of a range of hormone and neurotransmitter receptors allows δ-cells to integrate paracrine, endocrine, neural and nutritional inputs, and provide rapid and precise feedback modulations on glucagon and insulin secretion from α- and β-cells, respectively. Interestingly, the paracrine tone of δ-cells can be effectively modified in response to factors released by neighboring cells in this interactive communication, such as insulin, urocortin 3 and γ-aminobutyric acid from β-cells, glucagon, glutamate and glucagon-like peptide-1 from α-cells. In the setting of diabetes, defects in δ-cell function lead to suboptimal insulin and glucagon outputs and lift the glycemic set-point. The interaction of δ-cells and non-δ-cells also becomes defective in diabetes, with reduces paracrine feedback to β-cells to exacerbate hyperglycemia or enhanced inhibition of α-cells, disabling counter-regulation, to cause hypoglycemia. Thus, it is possible to restore/optimize islet function in diabetes targeting somatostatin signaling, which could open novel avenues for the development of effective diabetic treatments.
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Affiliation(s)
- Rui Gao
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LE, UK;
- Department of Endocrinology and Metabolism, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China;
| | - Tao Yang
- Department of Endocrinology and Metabolism, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China;
| | - Quan Zhang
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LE, UK;
- Correspondence:
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31
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A novel GPR120-selective agonist promotes insulin secretion and improves chronic inflammation. Life Sci 2021; 269:119029. [PMID: 33450256 DOI: 10.1016/j.lfs.2021.119029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 12/29/2020] [Accepted: 01/05/2021] [Indexed: 11/22/2022]
Abstract
AIMS The present study aimed to disclose a potent and selective GPR120 agonist LXT34 and its anti-diabetic effects. MAIN METHODS Calcium mobilization assay was used to measure the agonistic potency and selectivity of LXT34 in GPR120 or GPR40-overexpression Chinese hamster ovary (CHO) cells. Glucagon-like peptide-1 (GLP-1) release and glucose-stimulated insulin secretion (GSIS) were evaluated in human colonic epithelial cell line NCI-H716 and mouse insulinoma cell line MIN6 by enzyme-linked immunosorbent assay (ELISA), respectively. The anti-inflammatory effect was determined in lipopolysaccharide (LPS)-induced murine macrophage cell line RAW264.7. Oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) were performed to assess the anti-diabetic effects of LXT34 in db/db mice, and chronic inflammation in liver and adipose tissues were investigated using histomorphology, immunoblot and gene expression analysis. KEY FINDINGS LXT34 was a potent GPR120 agonist with negligible activity toward human and mouse GPR40. LXT34 could potentiate GSIS and suppress LPS-induced inflammation in macrophages. LXT34 not only markedly improved glucose tolerance and insulin resistance, but also distinctly reduced macrophages infiltration, pro-inflammatory cytokines expression and JNK phosphorylation of both liver and adipose tissues in db/db mice. SIGNIFICANCE LXT34, a novel and potent GPR120-selective agonist, showed beneficial effects on improving glucose homeostasis in obesity-related type 2 diabetes.
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32
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Son SE, Kim NJ, Im DS. Development of Free Fatty Acid Receptor 4 (FFA4/GPR120) Agonists in Health Science. Biomol Ther (Seoul) 2021; 29:22-30. [PMID: 33372166 PMCID: PMC7771848 DOI: 10.4062/biomolther.2020.213] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 11/28/2020] [Accepted: 11/30/2020] [Indexed: 12/14/2022] Open
Abstract
Till the 21st century, fatty acids were considered as merely building blocks for triglycerides, phospholipids, or cholesteryl esters. However, the discovery of G protein-coupled receptors (GPCRs) for free fatty acids at the beginning of the 21st century challenged that idea and paved way for a new field of research, merged into the field of receptor pharmacology for intercellular lipid mediators. Among the GPCRs for free fatty acids, free fatty acid receptor 4 (FFA4, also known as GPR120) recognizes long-chain polyunsaturated fatty acids such as DHA and EPA. It is significant in drug discovery because it regulates obesity-induced metaflammation and GLP-1 secretion. Our study reviews information on newly developed FFA4 agonists and their application in pathophysiologic studies and drug discovery. It also offers a potency comparison of the FFA4 agonists in an AP-TGF-α shedding assay.
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Affiliation(s)
- So-Eun Son
- Department of Pharmacy, College of Pharmacy, and Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Nam-Jung Kim
- Department of Pharmacy, College of Pharmacy, and Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Dong-Soon Im
- Department of Pharmacy, College of Pharmacy, and Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
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33
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Oliveira de Souza C, Sun X, Oh D. Metabolic Functions of G Protein-Coupled Receptors and β-Arrestin-Mediated Signaling Pathways in the Pathophysiology of Type 2 Diabetes and Obesity. Front Endocrinol (Lausanne) 2021; 12:715877. [PMID: 34497585 PMCID: PMC8419444 DOI: 10.3389/fendo.2021.715877] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 07/29/2021] [Indexed: 12/17/2022] Open
Abstract
Seven transmembrane receptors (7TMRs), often termed G protein-coupled receptors (GPCRs), are the most common target of therapeutic drugs used today. Many studies suggest that distinct members of the GPCR superfamily represent potential targets for the treatment of various metabolic disorders including obesity and type 2 diabetes (T2D). GPCRs typically activate different classes of heterotrimeric G proteins, which can be subgrouped into four major functional types: Gαs, Gαi, Gαq/11, and G12/13, in response to agonist binding. Accumulating evidence suggests that GPCRs can also initiate β-arrestin-dependent, G protein-independent signaling. Thus, the physiological outcome of activating a certain GPCR in a particular tissue may also be modulated by β-arrestin-dependent, but G protein-independent signaling pathways. In this review, we will focus on the role of G protein- and β-arrestin-dependent signaling pathways in the development of obesity and T2D-related metabolic disorders.
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34
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Wallis N, Raffan E. The Genetic Basis of Obesity and Related Metabolic Diseases in Humans and Companion Animals. Genes (Basel) 2020; 11:E1378. [PMID: 33233816 PMCID: PMC7699880 DOI: 10.3390/genes11111378] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/13/2020] [Accepted: 11/16/2020] [Indexed: 12/18/2022] Open
Abstract
Obesity is one of the most prevalent health conditions in humans and companion animals globally. It is associated with premature mortality, metabolic dysfunction, and multiple health conditions across species. Obesity is, therefore, of importance in the fields of medicine and veterinary medicine. The regulation of adiposity is a homeostatic process vulnerable to disruption by a multitude of genetic and environmental factors. It is well established that the heritability of obesity is high in humans and laboratory animals, with ample evidence that the same is true in companion animals. In this review, we provide an overview of how genes link to obesity in humans, drawing on a wealth of information from laboratory animal models, and summarise the mechanisms by which obesity causes related disease. Throughout, we focus on how large-scale human studies and niche investigations of rare mutations in severely affected patients have improved our understanding of obesity biology and can inform our ability to interpret results of animal studies. For dogs, cats, and horses, we compare the similarities in obesity pathophysiology to humans and review the genetic studies that have been previously reported in those species. Finally, we discuss how veterinary genetics may learn from humans about studying precise, nuanced phenotypes and implementing large-scale studies, but also how veterinary studies may be able to look past clinical findings to mechanistic ones and demonstrate translational benefits to human research.
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Affiliation(s)
- Natalie Wallis
- Anatomy Building, Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Eleanor Raffan
- Anatomy Building, Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
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35
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O'Connell TD, Mason RP, Budoff MJ, Navar AM, Shearer GC. Mechanistic insights into cardiovascular protection for omega-3 fatty acids and their bioactive lipid metabolites. Eur Heart J Suppl 2020; 22:J3-J20. [PMID: 33061864 PMCID: PMC7537803 DOI: 10.1093/eurheartj/suaa115] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Patients with well-controlled low-density lipoprotein cholesterol levels, but persistent high triglycerides, remain at increased risk for cardiovascular events as evidenced by multiple genetic and epidemiologic studies, as well as recent clinical outcome trials. While many trials of low-dose ω3-polyunsaturated fatty acids (ω3-PUFAs), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) have shown mixed results to reduce cardiovascular events, recent trials with high-dose ω3-PUFAs have reignited interest in ω3-PUFAs, particularly EPA, in cardiovascular disease (CVD). REDUCE-IT demonstrated that high-dose EPA (4 g/day icosapent-ethyl) reduced a composite of clinical events by 25% in statin-treated patients with established CVD or diabetes and other cardiovascular risk factors. Outcome trials in similar statin-treated patients using DHA-containing high-dose ω3 formulations have not yet shown the benefits of EPA alone. However, there are data to show that high-dose ω3-PUFAs in patients with acute myocardial infarction had reduced left ventricular remodelling, non-infarct myocardial fibrosis, and systemic inflammation. ω3-polyunsaturated fatty acids, along with their metabolites, such as oxylipins and other lipid mediators, have complex effects on the cardiovascular system. Together they target free fatty acid receptors and peroxisome proliferator-activated receptors in various tissues to modulate inflammation and lipid metabolism. Here, we review these multifactorial mechanisms of ω3-PUFAs in view of recent clinical findings. These findings indicate physico-chemical and biological diversity among ω3-PUFAs that influence tissue distributions as well as disparate effects on membrane organization, rates of lipid oxidation, as well as various receptor-mediated signal transduction pathways and effects on gene expression.
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Affiliation(s)
- Timothy D O'Connell
- Department of Integrative Biology and Physiology, University of Minnesota, 3-141 CCRB, 2231 6th Street SE, Minneapolis, MN 55414, USA
| | - Richard Preston Mason
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Matthew J Budoff
- Cardiovascular Division, Department of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Ann Marie Navar
- Cardiovascular Division, Duke Clinical Research Institute, Duke University, Durham, NC, USA
| | - Gregory C Shearer
- Department of Nutritional Sciences, The Pennsylvania State University, 110 Chandlee Laboratory, University Park, PA 16802, USA
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Xu F, Wang P, Zhang X, Hou T, Qu L, Wang C, Wang J, Liu Y, Liang X. Identification and target-pathway deconvolution of FFA4 agonists with anti-diabetic activity from Arnebia euchroma (Royle) Johnst. Pharmacol Res 2020; 163:105173. [PMID: 33027715 DOI: 10.1016/j.phrs.2020.105173] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/01/2020] [Accepted: 08/19/2020] [Indexed: 01/04/2023]
Abstract
FFA4 is a novel therapeutic target for the treatment of metabolic diseases, such as type II diabetes. However, there are still few ligands with structural diversity, selectivity and high potency, and the signaling pathway downstream of FFA4 remains to be poorly characterized. In this study, a high performance liquid chromatography-corona charged aerosol detector (HPLC-CAD) combined with label-free dynamic mass redistribution (DMR) method was introduced to guide the discovery of FFA4 agonists from Arnebia euchroma (Royle) Johnst. Ten compounds were identified as FFA4 agonists and structure-activity relationship was obtained. Among them, shikonin displayed the most potent activity with pEC50 value of 6.02 ± 0.19. The activity of shikonin was confirmed by FLIPR (fluorometric imaging plate reader) assay. Signaling pathways of FFA4 were explored in HT-29 cells endogenously expressing FFA4 using shikonin and known FFA4 agonists α-linolenic acid (ALA) and TUG891. Multiple pathways included Gq/11-PLC-Ca2+-PKC, RohA, JNK, p38 MAPK, Gi/o and PI3K signaling but may not involve Gs signaling triggered by shikonin, ALA and TUG891. Besides, shikonin, TUG891 and ALA could induce ERK1/2 and AKT phosphorylation in HT-29 cells. Moreover, anti-diabetes effects of shikonin were evaluated on the glucose intolerance in diabetic db/db mice. Shikonin reduced plasma glucose level, suggesting that it had the potential in treatment of type II diabetes. The agonists identified in this study provided structure guidance for FFA4 drug design. This study was also useful for understanding FFA4 pharmacology and its biological function.
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Affiliation(s)
- Fangfang Xu
- Key Lab of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Pan Wang
- Key Lab of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiuli Zhang
- College of Pharmaceutical Sciences, Soochow University, Suzhou, 215006, China
| | - Tao Hou
- Key Lab of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Lala Qu
- Key Lab of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chaoran Wang
- Key Lab of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Jixia Wang
- Key Lab of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
| | - Yanfang Liu
- Key Lab of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
| | - Xinmiao Liang
- Key Lab of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
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37
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Zhi D, Zhang M, Lin J, Liu P, Duan M. GPR120 Ameliorates Apoptosis and Inhibits the Production of Inflammatory Cytokines in Renal Tubular Epithelial Cells. Inflammation 2020; 44:493-505. [PMID: 33009637 DOI: 10.1007/s10753-020-01346-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/17/2020] [Accepted: 09/14/2020] [Indexed: 12/20/2022]
Abstract
Acute kidney injury (AKI) is the most common complication of sepsis with a high mortality rate. In this study, we focus on the renal injury caused by the immune response of renal tubular epithelial cells and inflammation-induced renal tubular epithelial cell apoptosis. We studied the role of GRP120 in the inflammation and apoptosis of human renal cell line HK-2 and mouse primary renal tubular epithelial cells. GPR120 agonist GW9508 activated the GPR120 pathway. Inflammatory factors were detected using quantitative real-time PCR and enzyme-linked immunosorbent assay. Cell apoptosis experiments included the annexin V and PI double-staining method combined with flow cytometry, TUNEL method, and Western blot. The level of cytokines including TNF-α, IL-6, IL-1β, and iNOS was significantly decreased (P < 0.05) in HK-2 and TECs after the activation of the GPR120 pathway. Besides, the cell apoptosis of both cells increased. Overexpressed GPR120 and shGPR120 were established. Treatment with lipopolysaccharide (LPS) increased the level of cytokines including TNF-α, IL-6, IL-1β, and iNOS in HK-2 cell and TECs. Compared with control-LPS and negative control (NC)-LPS, the overexpression of GPR120 and shGPR120 could decrease and increase the level of secreted cytokines significantly (P < 0.05), respectively, after LPS-induced apoptosis. After H2O2- and LPS-induced apoptosis, respectively, compared with the control and NC groups, overexpressed GPR120 and shGPR120 could reduce and increase the expression of caspase-3, respectively. GPR120 could suppress the cellular immune response and apoptosis in renal tubular epithelial cells, thereby possibly protecting the kidney and relieving sepsis-induced AKI.
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Affiliation(s)
- Deyuan Zhi
- Department of Critical Care Medicine, Beijing Friendship Hospital, Capital Medical University, No. 95 Yong'an Road, Xicheng District, Beijing, 100050, China
| | - Meng Zhang
- Department of Critical Care Medicine, Beijing Friendship Hospital, Capital Medical University, No. 95 Yong'an Road, Xicheng District, Beijing, 100050, China
| | - Jin Lin
- Department of Critical Care Medicine, Beijing Friendship Hospital, Capital Medical University, No. 95 Yong'an Road, Xicheng District, Beijing, 100050, China
| | - Pei Liu
- Department of Critical Care Medicine, Beijing Friendship Hospital, Capital Medical University, No. 95 Yong'an Road, Xicheng District, Beijing, 100050, China
| | - Meili Duan
- Department of Critical Care Medicine, Beijing Friendship Hospital, Capital Medical University, No. 95 Yong'an Road, Xicheng District, Beijing, 100050, China.
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38
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Zhao YF, Li XC, Liang XY, Zhao YY, Xie R, Zhang LJ, Zhang XC, Chen C. GPR120 Regulates Pancreatic Polypeptide Secretion From Male Mouse Islets via PLC-Mediated Calcium Mobilization. Endocrinology 2020; 161:5900686. [PMID: 32877513 DOI: 10.1210/endocr/bqaa157] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 08/29/2020] [Indexed: 02/07/2023]
Abstract
The free fatty acid receptor G protein-coupled receptor 120 (GPR120) is expressed in pancreatic islets, but its specific cell distribution and function have not been fully established. In this study, a GPR120-IRES-EGFP knockin (KI) mouse was generated to identify GPR120-expressing cells with enhanced green fluorescence proteins (EGFP). EGFP-positive cells collected from KI mouse islets by flow cytometry had a significantly higher expression of pancreatic polypeptide (PP) evidenced by reverse transcriptase (RT)-quantitative polymerase chain reaction (qPCR). Single-cell RT-PCR and immunocytochemical double staining also demonstrated the coexpression of GPR120 with PP in mouse islets. The GPR120-specific agonist TUG-891 significantly increased plasma PP levels in mice. TUG-891 significantly increased PP levels in islet medium in vitro, which was markedly attenuated by GPR120 small interfering RNA treatment. TUG-891-stimulated PP secretion in islets was fully blocked by pretreatment with YM-254890 (a Gq protein inhibitor), U73122 (a phospholipase C inhibitor), or thapsigargin (an inducer of endoplasmic reticulum Ca2+ depletion), respectively. TUG-891 triggered the increase in intracellular free Ca2+ concentrations ([Ca2+]i) in PP cells, which was also eliminated by YM-254890, U73122, or thapsigargin. GPR120 gene expression was significantly reduced in islets of high-fat diet (HFD)-induced obese mice. TUG-891-stimulated PP secretion was also significantly diminished in vivo and in vitro in HFD-induced obese mice compared with that in normal-chow diet control mice. In summary, this study demonstrated that GPR120 is expressed in mouse islet PP cells and GPR120 activation stimulated PP secretion via the Gq/PLC-Ca2+ signaling pathway in normal-chow diet mice but with diminished effects in HFD-induced obese mice.
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Affiliation(s)
- Yu-Feng Zhao
- Institute of Basic Medical Sciences, Xi'an Medical University, Xi'an, China
| | - Xiao-Cheng Li
- Institute of Basic Medical Sciences, Xi'an Medical University, Xi'an, China
| | - Xiang-Yan Liang
- Institute of Basic Medical Sciences, Xi'an Medical University, Xi'an, China
| | - Yan-Yan Zhao
- Institute of Basic Medical Sciences, Xi'an Medical University, Xi'an, China
| | - Rong Xie
- Institute of Basic Medical Sciences, Xi'an Medical University, Xi'an, China
| | - Li-Jun Zhang
- Institute of Basic Medical Sciences, Xi'an Medical University, Xi'an, China
| | - Xiao-Chun Zhang
- Institute of Basic Medical Sciences, Xi'an Medical University, Xi'an, China
| | - Chen Chen
- School of Biomedical Sciences, University of Queensland, Brisbane, Australia
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39
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Li B, Li L, Wang W, Meng J, Xu F, Wu F, Zhang G. Characterization of Free Fatty Acid Receptor 4 and Its Involvement in Nutritional Control and Immune Response in Pacific Oysters ( Crassostrea gigas). ACS OMEGA 2020; 5:21355-21363. [PMID: 32905352 PMCID: PMC7469124 DOI: 10.1021/acsomega.0c01325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 07/30/2020] [Indexed: 06/11/2023]
Abstract
Free fatty acid receptor 4 (FFAR4) has various physiological functions, including energy regulation and immunological homeostasis. We examined the only FFAR4 homologue in the Pacific oyster Crassostrea gigas (CgFFAR4), which functions as a sensor of long-chain fatty acids. CgFFAR4 is 1098 bp long and contains a seven-transmembrane G protein-coupled receptor domain. CgFFAR4 expression was high in the hepatopancreas, but it was downregulated after fasting, indicating that it plays an essential role in food digestion. Lipopolysaccharide stimulation downregulated CgFFAR4 level, probably as an immune response of the animal. Reduced glycogen level alongside decreased insulin receptor, insulin receptor substrate, and C. gigas glycogen synthase transcription levels after CgFFAR4 knockdown revealed that CgFFAR4 was involved in the regulation of fatty acid and glycogen levels via the insulin pathway. Accordingly, this is the first study on an invertebrate FFAR and provides new insights into the role of this receptor in immune response and nutritional control.
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Affiliation(s)
- Busu Li
- Key
Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
- National
and Local Joint Engineering Laboratory of Ecological Mariculture, Qingdao 266071, China
| | - Li Li
- Key
Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- Center
for Ocean Mega-Science, Chinese Academy
of Sciences, Qingdao 266071, China
- National
and Local Joint Engineering Laboratory of Ecological Mariculture, Qingdao 266071, China
- Laboratory
for Marine Fisheries and Aquaculture, Pilot
National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Wei Wang
- Key
Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- National
and Local Joint Engineering Laboratory of Ecological Mariculture, Qingdao 266071, China
| | - Jie Meng
- Key
Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- National
and Local Joint Engineering Laboratory of Ecological Mariculture, Qingdao 266071, China
| | - Fei Xu
- Key
Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- Center
for Ocean Mega-Science, Chinese Academy
of Sciences, Qingdao 266071, China
- National
and Local Joint Engineering Laboratory of Ecological Mariculture, Qingdao 266071, China
| | - Fucun Wu
- Key
Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
- The
Innovation of Seed Design, Chinese Academy
of Sciences, Wuhan 430072, P. R. China
| | - Guofan Zhang
- Key
Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
- Center
for Ocean Mega-Science, Chinese Academy
of Sciences, Qingdao 266071, China
- National
and Local Joint Engineering Laboratory of Ecological Mariculture, Qingdao 266071, China
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40
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Reduced somatostatin signalling leads to hypersecretion of glucagon in mice fed a high-fat diet. Mol Metab 2020; 40:101021. [PMID: 32446876 PMCID: PMC7322681 DOI: 10.1016/j.molmet.2020.101021] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/11/2020] [Accepted: 05/14/2020] [Indexed: 11/29/2022] Open
Abstract
Objectives Elevated plasma glucagon is an early symptom of diabetes, occurring in subjects with impaired glucose regulation. Here, we explored alpha-cell function in female mice fed a high-fat diet (HFD). Methods Female mice expressing the Ca2+ indicator GCaMP3 specifically in alpha-cells were fed a high-fat or control (CTL) diet. We then conducted in vivo phenotyping of these mice, as well as experiments on isolated (ex vivo) islets and in the in situ perfused pancreas. Results In HFD-fed mice, fed plasma glucagon levels were increased and glucagon secretion from isolated islets and in the perfused mouse pancreas was also elevated. In mice fed a CTL diet, increasing glucose reduced intracellular Ca2+ ([Ca2+]i) oscillation frequency and amplitude. This effect was also observed in HFD mice; however, both the frequency and amplitude of the [Ca2+]i oscillations were higher than those in CTL alpha-cells. Given that alpha-cells are under strong paracrine control from neighbouring somatostatin-secreting delta-cells, we hypothesised that this elevation of alpha-cell output was due to a lack of somatostatin (SST) secretion. Indeed, SST secretion in isolated islets from HFD-fed mice was reduced but exogenous SST also failed to suppress glucagon secretion and [Ca2+]i activity from HFD alpha-cells, in contrast to observations in CTL mice. Conclusions These findings suggest that reduced delta-cell function, combined with intrinsic changes in alpha-cells including sensitivity to somatostatin, accounts for the hyperglucagonaemia in mice fed a HFD. HFD feeding causes hyperglucagonaemia in vivo. Glucagon is inadequately suppressed by glucose in HFD-fed mice. Alpha-cell [Ca2+]i oscillations and glucagon output are elevated ex vivo in response to HFD feeding. SST secretion from HFD islets is reduced. Alpha-cells from HFD-fed mice become ‘resistant’ to SST.
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41
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Reimann F, Diakogiannaki E, Hodge D, Gribble FM. Cellular mechanisms governing glucose-dependent insulinotropic polypeptide secretion. Peptides 2020; 125:170206. [PMID: 31756367 DOI: 10.1016/j.peptides.2019.170206] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 11/13/2019] [Accepted: 11/14/2019] [Indexed: 02/01/2023]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) is a gut hormone secreted from the upper small intestine, which plays an important physiological role in the control of glucose metabolism through its incretin action to enhance glucose-dependent insulin secretion. GIP has also been implicated in postprandial lipid homeostasis. GIP is secreted from enteroendocrine K-cells residing in the intestinal epithelium. K-cells sense a variety of components found in the gut lumen following food consumption, resulting in an increase in plasma GIP signal dependent on the nature and quantity of ingested nutrients. We review the evidence for an important role of sodium-coupled glucose uptake through SGLT1 for carbohydrate sensing, of free-fatty acid receptors FFAR1/FFAR4 and the monoacyl-glycerol sensing receptor GPR119 for lipid detection, of the calcium-sensing receptor CASR and GPR142 for protein sensing, and additional modulation by neurotransmitters such as somatostatin and galanin. These pathways have been identified through combinations of in vivo, in vitro and molecular approaches.
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Affiliation(s)
- Frank Reimann
- Wellcome Trust/MRC Institute of Metabolic Science (IMS), University of Cambridge, United Kingdom.
| | - Eleftheria Diakogiannaki
- Wellcome Trust/MRC Institute of Metabolic Science (IMS), University of Cambridge, United Kingdom
| | - Daryl Hodge
- Wellcome Trust/MRC Institute of Metabolic Science (IMS), University of Cambridge, United Kingdom
| | - Fiona M Gribble
- Wellcome Trust/MRC Institute of Metabolic Science (IMS), University of Cambridge, United Kingdom.
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Nakamura S, Noda K, Miwa M, Minabe S, Hagiwara T, Hirasawa A, Matsuyama S, Moriyama R. Colocalization of GPR120 and anterior pituitary hormone-producing cells in female Japanese Black cattle. J Reprod Dev 2019; 66:135-141. [PMID: 31902805 PMCID: PMC7175391 DOI: 10.1262/jrd.2019-111] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Negative energy balance in domestic animals suppresses their reproductive function. These animals commonly use long-chain fatty acids (LCFAs) from adipocytes as an energy source under
states of malnutrition. The G-protein coupled receptor, GPR120, is a specific receptor for LCFAs, but its role in reproductive function remains unknown in domestic animals. The purpose of
this study was to examine whether GPR120 is involved in the reproductive system of cattle. GPR120 mRNA expression was evaluated in brain, pituitary, and ovarian tissue
samples by RT-PCR. GPR120 gene expression was detected with high intensity only in the anterior pituitary sample, and GPR120-immunoreactive cells were found in the anterior
pituitary gland. Double immunohistochemistry of GPR120 in the anterior pituitary hormone-producing cells, such as gonadotropes, thyrotropes, lactotropes, somatotropes, and corticotropes, was
performed to clarify the distribution of GPR120 in the anterior pituitary gland of ovariectomized heifers. Luteinizing hormone β subunit (LHβ)- and follicle-stimulating hormone β subunit
(FSHβ)-immunoreactive cells demonstrated GPR120 immunoreactivity at 80.7% and 85.9%, respectively. Thyrotropes, lactotropes, somatotropes, and corticotropes coexpressed GPR120 at 21.1%,
5.4%, 13.6%, and 14.5%, respectively. In conclusion, the present study suggests that GPR120 in the anterior pituitary gland might mediate LCFA signaling to regulate gonadotrope functions,
such as hormone secretion or production, in cattle.
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Affiliation(s)
- Sho Nakamura
- Institute of Livestock and Grassland Science, National Agriculture and Food Research Organization (NARO-ILGS), Tochigi 329-2793, Japan.,Faculty of Veterinary Medicine, Okayama University of Science, Ehime 794-8555, Japan
| | - Kohei Noda
- Laboratory of Environmental physiology, Department of Life Science, Kindai University, Osaka 577-8502, Japan
| | - Masafumi Miwa
- Institute of Livestock and Grassland Science, National Agriculture and Food Research Organization (NARO-ILGS), Tochigi 329-2793, Japan
| | - Shiori Minabe
- Laboratory of Theriogenology, Department of Veterinary Medical Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Teruki Hagiwara
- Laboratory of Molecular and Cellular Biology, Department of Life Science, Kindai University, Osaka 577-8502, Japan
| | - Akira Hirasawa
- Graduate School of Pharmaceutical Science, Kyoto University, Kyoto 606-8501, Japan
| | - Shuichi Matsuyama
- Institute of Livestock and Grassland Science, National Agriculture and Food Research Organization (NARO-ILGS), Tochigi 329-2793, Japan.,Laboratory of Animal Production Science, Graduate School of Bioagricultural Sciences, Nagoya University, Aichi 464-8601, Japan
| | - Ryutaro Moriyama
- Laboratory of Environmental physiology, Department of Life Science, Kindai University, Osaka 577-8502, Japan
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Noguchi GM, Huising MO. Integrating the inputs that shape pancreatic islet hormone release. Nat Metab 2019; 1:1189-1201. [PMID: 32694675 PMCID: PMC7378277 DOI: 10.1038/s42255-019-0148-2] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 11/07/2019] [Indexed: 02/06/2023]
Abstract
The pancreatic islet is a complex mini organ composed of a variety of endocrine cells and their support cells, which together tightly control blood glucose homeostasis. Changes in glucose concentration are commonly regarded as the chief signal controlling insulin-secreting beta cells, glucagon-secreting alpha cells and somatostatin-secreting delta cells. However, each of these cell types is highly responsive to a multitude of endocrine, paracrine, nutritional and neural inputs, which collectively shape the final endocrine output of the islet. Here, we review the principal inputs for each islet-cell type and the physiological circumstances in which these signals arise, through the prism of the insights generated by the transcriptomes of each of the major endocrine-cell types. A comprehensive integration of the factors that influence blood glucose homeostasis is essential to successfully improve therapeutic strategies for better diabetes management.
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Affiliation(s)
- Glyn M Noguchi
- Department of Neurobiology, Physiology & Behavior, College of Biological Sciences, University of California, Davis, Davis, CA, USA
| | - Mark O Huising
- Department of Neurobiology, Physiology & Behavior, College of Biological Sciences, University of California, Davis, Davis, CA, USA.
- Department of Physiology & Membrane Biology, School of Medicine, University of California, Davis, Davis, CA, USA.
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Abstract
Olfactory and taste receptors are expressed primarily in the nasal olfactory epithelium and gustatory taste bud cells, where they transmit real-time sensory signals to the brain. However, they are also expressed in multiple extra-nasal and extra-oral tissues, being implicated in diverse biological processes including sperm chemotaxis, muscle regeneration, bronchoconstriction and bronchodilatation, inflammation, appetite regulation and energy metabolism. Elucidation of the physiological roles of these ectopic receptors is revealing potential therapeutic and diagnostic applications in conditions including wounds, hair loss, asthma, obesity and cancers. This Review outlines current understanding of the diverse functions of ectopic olfactory and taste receptors and assesses their potential to be therapeutically exploited.
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Pharmacological potential of novel agonists for FFAR4 on islet and enteroendocrine cell function and glucose homeostasis. Eur J Pharm Sci 2019; 142:105104. [PMID: 31669388 DOI: 10.1016/j.ejps.2019.105104] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 09/27/2019] [Accepted: 10/10/2019] [Indexed: 12/15/2022]
Abstract
BACKGROUND To investigate the metabolic effects of FFAR4-selective agonists on islet and enteroendocrine cell hormone release and the combined therapeutic effectiveness with DPP-IV inhibitors. METHODS Insulinotropic activity and specificity of FFAR4 agonists were determined in clonal pancreatic BRIN-BD11 cells. Expression of FFAR4 was assessed by qPCR and western blotting following agonist treatment in BRIN-BD11 cells and by immunohistochemistry in mouse islets. Acute in-vivo effects of agonists was investigated after intraperitoneal (i.p.) or oral administration in lean and HFF-obese diabetic mice. RESULTS GSK137647 (10-11-10-4 M) and Compound-A (10-10-10-4 M) stimulated insulin secretion at 5.6 mM (p < 0.05-p < 0.001) and 16.7 mM (p < 0.05-p < 0.001) glucose in BRIN-BD11 cells, with no cytotoxicity effects as assessed by MTT. FFAR4 antagonist (AH-7614) abolished the insulintropic effect of GSK137647 (p < 0.05-p < 0.001), whilst FFAR1 antagonist (GW1100) had no effect. Incubation of BRIN-BD11 cells with GSK137647 and Compound-A increased FFAR4 (p < 0.01) gene expression at 16.7 mM glucose, with a corresponding increase in FFAR4 (p < 0.01) protein concentrations. FFAR4 upregulation was attenuated under normoglycaemic conditions. Immunohistochemistry demonstrated co-localisation of FFAR4 and insulin in mouse islets. Orally administered GSK137647 or Compound-A (0.1 µmol/kgBW) improved glucose tolerance (p < 0.001), increased plasma insulin (p < 0.001), GLP-1 (p < 0.05), GIP (p < 0.05) and induced satiety (p < 0.001) in HFF mice, with glucose-lowering effects enhanced in combination with DPP-IV inhibitor (Sitagliptin) (p < 0.05). CONCLUSIONS Specific FFAR4 agonism improves glucose tolerance through insulin and incretin secretion, with enhanced DPP-IV inhibition in combination with Sitagliptin. GENERAL SIGNIFICANCE These findings have for the first time demonstrated that selective FFAR4 activation regulates both islet and enteroendocrine hormone function with agonist combinational therapy, presenting a promising strategy for the treatment of type-2-diabetes.
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Kimura I, Ichimura A, Ohue-Kitano R, Igarashi M. Free Fatty Acid Receptors in Health and Disease. Physiol Rev 2019; 100:171-210. [PMID: 31487233 DOI: 10.1152/physrev.00041.2018] [Citation(s) in RCA: 460] [Impact Index Per Article: 92.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Fatty acids are metabolized and synthesized as energy substrates during biological responses. Long- and medium-chain fatty acids derived mainly from dietary triglycerides, and short-chain fatty acids (SCFAs) produced by gut microbial fermentation of the otherwise indigestible dietary fiber, constitute the major sources of free fatty acids (FFAs) in the metabolic network. Recently, increasing evidence indicates that FFAs serve not only as energy sources but also as natural ligands for a group of orphan G protein-coupled receptors (GPCRs) termed free fatty acid receptors (FFARs), essentially intertwining metabolism and immunity in multiple ways, such as via inflammation regulation and secretion of peptide hormones. To date, several FFARs that are activated by the FFAs of various chain lengths have been identified and characterized. In particular, FFAR1 (GPR40) and FFAR4 (GPR120) are activated by long-chain saturated and unsaturated fatty acids, while FFAR3 (GPR41) and FFAR2 (GPR43) are activated by SCFAs, mainly acetate, butyrate, and propionate. In this review, we discuss the recent reports on the key physiological functions of the FFAR-mediated signaling transduction pathways in the regulation of metabolism and immune responses. We also attempt to reveal future research opportunities for developing therapeutics for metabolic and immune disorders.
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Affiliation(s)
- Ikuo Kimura
- Department of Applied Biological Science, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Fuchu-shi, Tokyo, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo, Japan; and Department of Biochemistry, Kyoto University Graduate School of Pharmaceutical Science, Sakyo, Kyoto, Japan
| | - Atsuhiko Ichimura
- Department of Applied Biological Science, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Fuchu-shi, Tokyo, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo, Japan; and Department of Biochemistry, Kyoto University Graduate School of Pharmaceutical Science, Sakyo, Kyoto, Japan
| | - Ryuji Ohue-Kitano
- Department of Applied Biological Science, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Fuchu-shi, Tokyo, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo, Japan; and Department of Biochemistry, Kyoto University Graduate School of Pharmaceutical Science, Sakyo, Kyoto, Japan
| | - Miki Igarashi
- Department of Applied Biological Science, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Fuchu-shi, Tokyo, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo, Japan; and Department of Biochemistry, Kyoto University Graduate School of Pharmaceutical Science, Sakyo, Kyoto, Japan
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Dao NC, Brockway DF, Crowley NA. In Vitro Optogenetic Characterization of Neuropeptide Release from Prefrontal Cortical Somatostatin Neurons. Neuroscience 2019; 419:1-4. [PMID: 31487544 DOI: 10.1016/j.neuroscience.2019.08.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 08/06/2019] [Accepted: 08/07/2019] [Indexed: 12/16/2022]
Abstract
Somatostatin is a neuropeptide thought to play a role in a variety of neuropsychiatric disorders, and is important for healthy aging and behavioral resiliency. Physiological conditions underlying somatostatin peptidergic release are not well-defined. Using a combination of optogenetic and biochemical approaches in transgenic mice, we demonstrate an assay for the induction and inhibition of somatostatin release in mouse acute brain slices.
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Affiliation(s)
- Nigel C Dao
- Department of Biobehavioral Health, Pennsylvania State University, University Park, PA 16802
| | - Dakota F Brockway
- Department of Biobehavioral Health, Pennsylvania State University, University Park, PA 16802; Neuroscience Curriculum, Pennsylvania State University, University Park, PA 16802
| | - Nicole A Crowley
- Department of Biobehavioral Health, Pennsylvania State University, University Park, PA 16802; Neuroscience Curriculum, Pennsylvania State University, University Park, PA 16802.
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48
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Targeting GPCRs Activated by Fatty Acid-Derived Lipids in Type 2 Diabetes. Trends Mol Med 2019; 25:915-929. [PMID: 31377146 DOI: 10.1016/j.molmed.2019.07.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 04/28/2019] [Accepted: 07/08/2019] [Indexed: 12/20/2022]
Abstract
G protein-coupled receptors (GPCRs) are the most intensively studied drug targets, because of their diversity, cell-specific expression, and druggable sites accessible at the cell surface. Preclinical and clinical studies suggest that targeting GPCRs activated by fatty acid-derived lipids may have potential to improve glucose homeostasis and reduce complications in patients with type 2 diabetes (T2D). Despite the discontinued development of fasiglifam (TAK-875), the first FFA1 agonist to reach late-stage clinical trials, lipid-sensing receptors remain a viable target, albeit with a need for further characterization of their binding mode, intracellular signaling, and toxicity. Herein, we analyze general discovery trends, various signaling pathways, as well as possible challenges following activation of GPCRs that have been validated clinically to control blood glucose levels.
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Huising MO, van der Meulen T, Huang JL, Pourhosseinzadeh MS, Noguchi GM. The Difference δ-Cells Make in Glucose Control. Physiology (Bethesda) 2019; 33:403-411. [PMID: 30303773 DOI: 10.1152/physiol.00029.2018] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The role of beta and α-cells to glucose control are established, but the physiological role of δ-cells is poorly understood. Delta-cells are ideally positioned within pancreatic islets to modulate insulin and glucagon secretion at their source. We review the evidence for a negative feedback loop between delta and β-cells that determines the blood glucose set point and suggest that local δ-cell-mediated feedback stabilizes glycemic control.
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Affiliation(s)
- Mark O Huising
- Department of Neurobiology, Physiology & Behavior, College of Biological Sciences, University of California , Davis, California.,Department of Physiology and Membrane Biology, School of Medicine, University of California , Davis, California
| | - Talitha van der Meulen
- Department of Neurobiology, Physiology & Behavior, College of Biological Sciences, University of California , Davis, California
| | - Jessica L Huang
- Department of Neurobiology, Physiology & Behavior, College of Biological Sciences, University of California , Davis, California
| | - Mohammad S Pourhosseinzadeh
- Department of Neurobiology, Physiology & Behavior, College of Biological Sciences, University of California , Davis, California
| | - Glyn M Noguchi
- Department of Neurobiology, Physiology & Behavior, College of Biological Sciences, University of California , Davis, California
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50
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GPR120 protects lipotoxicity-induced pancreatic β-cell dysfunction through regulation of PDX1 expression and inhibition of islet inflammation. Clin Sci (Lond) 2019; 133:101-116. [PMID: 30523046 DOI: 10.1042/cs20180836] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 11/29/2018] [Accepted: 12/05/2018] [Indexed: 12/23/2022]
Abstract
G-protein coupled receptor 120 (GPR120) has been shown to act as an omega-3 unsaturated fatty acid sensor and is involved in insulin secretion. However, the underlying mechanism in pancreatic β cells remains unclear. To explore the potential link between GPR120 and β-cell function, its agonists docosahexaenoic acid (DHA) and GSK137647A were used in palmitic acid (PA)-induced pancreatic β-cell dysfunction, coupled with GPR120 knockdown (KD) in MIN6 cells and GPR120 knockout (KO) mice to identify the underlying signaling pathways. In vitro and ex vivo treatments of MIN6 cells and islets isolated from wild-type (WT) mice with DHA and GSK137647A restored pancreatic duodenal homeobox-1 (PDX1) expression levels and β-cell function via inhibiting PA-induced elevation of proinflammatory chemokines and activation of nuclear factor κB, c-Jun amino (N)-terminal kinases1/2 and p38MAPK signaling pathways. On the contrary, these GPR120 agonism-mediated protective effects were abolished in GPR120 KD cells and islets isolated from GPR120 KO mice. Furthermore, GPR120 KO mice displayed glucose intolerance and insulin resistance relative to WT littermates, and β-cell functional related genes were decreased while inflammation was exacerbated in islets with increased macrophages in pancreas from GPR120 KO mice. DHA and GSK137647A supplementation ameliorated glucose tolerance and insulin sensitivity, as well as improved Pdx1 expression and islet inflammation in diet-induced obese WT mice, but not in GPR120 KO mice. These findings indicate that GPR120 activation is protective against lipotoxicity-induced pancreatic β-cell dysfunction, via the mediation of PDX1 expression and inhibition of islet inflammation, and that GPR120 activation may serve as a preventative and therapeutic target for obesity and diabetes.
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