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Jobe A, Vijayan R. Orphan G protein-coupled receptors: the ongoing search for a home. Front Pharmacol 2024; 15:1349097. [PMID: 38495099 PMCID: PMC10941346 DOI: 10.3389/fphar.2024.1349097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 02/15/2024] [Indexed: 03/19/2024] Open
Abstract
G protein-coupled receptors (GPCRs) make up the largest receptor superfamily, accounting for 4% of protein-coding genes. Despite the prevalence of such transmembrane receptors, a significant number remain orphans, lacking identified endogenous ligands. Since their conception, the reverse pharmacology approach has been used to characterize such receptors. However, the multifaceted and nuanced nature of GPCR signaling poses a great challenge to their pharmacological elucidation. Considering their therapeutic relevance, the search for native orphan GPCR ligands continues. Despite limited structural input in terms of 3D crystallized structures, with advances in machine-learning approaches, there has been great progress with respect to accurate ligand prediction. Though such an approach proves valuable given that ligand scarcity is the greatest hurdle to orphan GPCR deorphanization, the future pairings of the remaining orphan GPCRs may not necessarily take a one-size-fits-all approach but should be more comprehensive in accounting for numerous nuanced possibilities to cover the full spectrum of GPCR signaling.
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Affiliation(s)
- Amie Jobe
- Department of Biology, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Ranjit Vijayan
- Department of Biology, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates
- The Big Data Analytics Center, United Arab Emirates University, Al Ain, United Arab Emirates
- Zayed Bin Sultan Center for Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
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Kumari P, Inoue A, Chapman K, Lian P, Rosenbaum DM. Molecular mechanism of fatty acid activation of FFAR1. Proc Natl Acad Sci U S A 2023; 120:e2219569120. [PMID: 37216523 PMCID: PMC10235965 DOI: 10.1073/pnas.2219569120] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 04/03/2023] [Indexed: 05/24/2023] Open
Abstract
FFAR1 is a G-protein-coupled receptor (GPCR) that responds to circulating free fatty acids to enhance glucose-stimulated insulin secretion and release of incretin hormones. Due to the glucose-lowering effect of FFAR1 activation, potent agonists for this receptor have been developed for the treatment of diabetes. Previous structural and biochemical studies of FFAR1 showed multiple sites of ligand binding to the inactive state but left the mechanism of fatty acid interaction and receptor activation unknown. We used cryo-electron microscopy to elucidate structures of activated FFAR1 bound to a Gq mimetic, which were induced either by the endogenous FFA ligand docosahexaenoic acid or γ-linolenic acid and the agonist drug TAK-875. Our data identify the orthosteric pocket for fatty acids and show how both endogenous hormones and synthetic agonists induce changes in helical packing along the outside of the receptor that propagate to exposure of the G-protein-coupling site. These structures show how FFAR1 functions without the highly conserved "DRY" and "NPXXY" motifs of class A GPCRs and also illustrate how the orthosteric site of a receptor can be bypassed by membrane-embedded drugs to confer full activation of G protein signaling.
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Affiliation(s)
- Punita Kumari
- Department of Biophysics, The University of Texas Southwestern Medical Center, Dallas, TX75390
| | - Asuka Inoue
- Department of Pharmaceutical Sciences, Tohoku University, Sendai980-8578, Japan
| | - Karen Chapman
- Department of Biophysics, The University of Texas Southwestern Medical Center, Dallas, TX75390
| | - Peng Lian
- BioHPC at the Lyda Hill Department of Bioinformatics, The University of Texas Southwestern Medical Center, Dallas, TX75390
| | - Daniel M. Rosenbaum
- Department of Biophysics, The University of Texas Southwestern Medical Center, Dallas, TX75390
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Teng D, Zhou Y, Tang Y, Liu G, Tu Y. Mechanistic Studies on the Stereoselectivity of FFAR1 Modulators. J Chem Inf Model 2022; 62:3664-3675. [PMID: 35877470 PMCID: PMC9364411 DOI: 10.1021/acs.jcim.2c00417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Free fatty acid receptor 1 (FFAR1) is a potential therapeutic target for the treatment of type 2 diabetes (T2D). It has been validated that agonists targeting FFAR1 can achieve the initial therapeutic endpoints of T2D, and the epimer agonists (R,S) AM-8596 can activate FFAR1 differently, with one acting as a partial agonist and the other as a full agonist. Up to now, the origin of the stereoselectivity of FFAR1 agonists remains elusive. In this work, we used molecular simulation methods to elucidate the mechanism of the stereoselectivity of the FFAR1 agonists (R)-AM-8596 and (S)-AM-8596. We found that the full agonist (R)-AM-8596 disrupts the residue interaction network around the receptor binding pocket and promotes the opening of the binding site for the G-protein, thereby resulting in the full activation of FFAR1. In contrast, the partial agonist (S)-AM-8596 forms stable electrostatic interactions with FFAR1, which stabilizes the residue network and hinders the conformational transition of the receptor. Our work thus clarifies the selectivity and underlying molecular activation mechanism of FFAR1 agonists.
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Affiliation(s)
- Dan Teng
- Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China.,Department of Theoretical Chemistry and Biology, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), KTH Royal Institute of Technology, Stockholm SE-106 91, Sweden
| | - Yang Zhou
- School of Pharmacy, Jinan University, 601 Huangpu Avenue West, Guangzhou 510632, China
| | - Yun Tang
- Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Guixia Liu
- Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Yaoquan Tu
- Department of Theoretical Chemistry and Biology, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), KTH Royal Institute of Technology, Stockholm SE-106 91, Sweden
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In Silico Searching for Alternative Lead Compounds to Treat Type 2 Diabetes through a QSAR and Molecular Dynamics Study. Pharmaceutics 2022; 14:pharmaceutics14020232. [PMID: 35213965 PMCID: PMC8879932 DOI: 10.3390/pharmaceutics14020232] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/28/2021] [Accepted: 01/07/2022] [Indexed: 02/01/2023] Open
Abstract
Free fatty acid receptor 1 (FFA1) stimulates insulin secretion in pancreatic β-cells. An advantage of therapies that target FFA1 is their reduced risk of hypoglycemia relative to common type 2 diabetes treatments. In this work, quantitative structure–activity relationship (QSAR) approach was used to construct models to identify possible FFA1 agonists by applying four different machine-learning algorithms. The best model (M2) meets the Tropsha’s test requirements and has the statistics parameters R2 = 0.843, Q2CV = 0.785, and Q2ext = 0.855. Also, coverage of 100% of the test set based on the applicability domain analysis was obtained. Furthermore, a deep analysis based on the ADME predictions, molecular docking, and molecular dynamics simulations was performed. The lipophilicity and the residue interactions were used as relevant criteria for selecting a candidate from the screening of the DiaNat and DrugBank databases. Finally, the FDA-approved drugs bilastine, bromfenac, and fenofibric acid are suggested as potential and lead FFA1 agonists.
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Liu T, Ji RL, Tao YX. Naturally occurring mutations in G protein-coupled receptors associated with obesity and type 2 diabetes mellitus. Pharmacol Ther 2021; 234:108044. [PMID: 34822948 DOI: 10.1016/j.pharmthera.2021.108044] [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: 09/01/2021] [Revised: 11/15/2021] [Accepted: 11/15/2021] [Indexed: 12/12/2022]
Abstract
G protein-coupled receptors (GPCRs) are the largest family of membrane receptors involved in the regulation of almost all known physiological processes. Dysfunctions of GPCR-mediated signaling have been shown to cause various diseases. The prevalence of obesity and type 2 diabetes mellitus (T2DM), two strongly associated disorders, is increasing worldwide, with tremendous economical and health burden. New safer and more efficacious drugs are required for successful weight reduction and T2DM treatment. Multiple GPCRs are involved in the regulation of energy and glucose homeostasis. Mutations in these GPCRs contribute to the development and progression of obesity and T2DM. Therefore, these receptors can be therapeutic targets for obesity and T2DM. Indeed some of these receptors, such as melanocortin-4 receptor and glucagon-like peptide 1 receptor, have provided important new drugs for treating obesity and T2DM. This review will focus on the naturally occurring mutations of several GPCRs associated with obesity and T2DM, especially incorporating recent large genomic data and insights from structure-function studies, providing leads for future investigations.
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Affiliation(s)
- Ting Liu
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL 36849, United States
| | - Ren-Lei Ji
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL 36849, United States
| | - Ya-Xiong Tao
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL 36849, United States.
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Free fatty acid receptor 1: a ray of hope in the therapy of type 2 diabetes mellitus. Inflammopharmacology 2021; 29:1625-1639. [PMID: 34669065 DOI: 10.1007/s10787-021-00879-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 09/21/2021] [Indexed: 12/25/2022]
Abstract
Free fatty acid receptor 1 (FFAR1) is a G-protein coupled receptor with prominent expression on pancreatic beta cells, bones, intestinal cells as well as the nerve cells. This receptor mediates a multitude of functions in the body including release of incretins, secretion of insulin as well as sensation of pain. Since FFAR1 causes secretion of insulin and regulates glucose metabolism, efforts were made to unfold its structure followed by discovering agonists for the receptor and the utilization of these agonists in the therapy of type 2 diabetes mellitus. Development of such functional FFAR1 agonists is a necessity because the currently available therapy for type 2 diabetes mellitus has numerous drawbacks, of which, the major one is hypoglycemia. Since the most prominent effect of the FFAR1 agonists is on glucose concentration in the body, so the major research is focused on treating type 2 diabetes mellitus, though the agonists could benefit other metabolic disorders and neurological disorders as well. The agonists developed so far had one major limitation, i.e., hepatotoxicity. Although, the only agonist that could reach phase 3 clinical trials was TAK-875 developed by Takeda Pharmaceuticals but it was also withdrawn due to toxic effects on the liver. Thus, there are numerous agonists for the varied binding sites of the receptor but no drug available yet. There does seem to be a ray of hope in the drugs that target FFAR1 but a lot more efforts towards drug discovery would result in the successful management of type 2 diabetes mellitus.
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Rani L, Grewal AS, Sharma N, Singh S. Recent Updates on Free Fatty Acid Receptor 1 (GPR-40) Agonists for the Treatment of Type 2 Diabetes Mellitus. Mini Rev Med Chem 2021; 21:426-470. [PMID: 33100202 DOI: 10.2174/1389557520666201023141326] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 09/09/2020] [Accepted: 09/14/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND The global incidence of type 2 diabetes mellitus (T2DM) has enthused the development of new antidiabetic targets with low toxicity and long-term stability. In this respect, free fatty acid receptor 1 (FFAR1), which is also recognized as a G protein-coupled receptor 40 (GPR40), is a novel target for the treatment of T2DM. FFAR1/GPR40 has a high level of expression in β-cells of the pancreas, and the requirement of glucose for stimulating insulin release results in immense stimulation to utilise this target in the medication of T2DM. METHODS The data used for this review is based on the search of several scienctific databases as well as various patent databases. The main search terms used were free fatty acid receptor 1, FFAR1, FFAR1 agonists, diabetes mellitus, G protein-coupled receptor 40 (GPR40), GPR40 agonists, GPR40 ligands, type 2 diabetes mellitus and T2DM. RESULTS The present review article gives a brief overview of FFAR1, its role in T2DM, recent developments in small molecule FFAR1 (GPR40) agonists reported till now, compounds of natural/plant origin, recent patents published in the last few years, mechanism of FFAR1 activation by the agonists, and clinical status of the FFAR1/GPR40 agonists. CONCLUSION The agonists of FFAR1/GRP40 showed considerable potential for the therapeutic control of T2DM. Most of the small molecule FFAR1/GPR40 agonists developed were aryl alkanoic acid derivatives (such as phenylpropionic acids, phenylacetic acids, phenoxyacetic acids, and benzofuran acetic acid derivatives) and thiazolidinediones. Some natural/plant-derived compounds, including fatty acids, sesquiterpenes, phenolic compounds, anthocyanins, isoquinoline, and indole alkaloids, were also reported as potent FFAR1 agonists. The clinical investigations of the FFAR1 agonists demonstrated their probable role in the improvement of glucose control. Though, there are some problems still to be resolved in this field as some FFAR1 agonists terminated in the late phase of clinical studies due to "hepatotoxicity." Currently, PBI-4050 is under clinical investigation by Prometic. Further investigation of pharmacophore scaffolds for FFAR1 full agonists as well as multitargeted modulators and corresponding clinical investigations will be anticipated, which can open up new directions in this area.
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Affiliation(s)
- Lata Rani
- Chitkara University School of Basic Sciences, Chitkara University, Himachal Pradesh, India
| | - Ajmer Singh Grewal
- Chitkara University School of Basic Sciences, Chitkara University, Himachal Pradesh, India
| | - Neelam Sharma
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Sukhbir Singh
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
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Yan Y, Xu Q, Zhao C, Dong H, Xu W, Zhang Y. In vivo pharmacokinetic study and oral glucose tolerance test of sulfoxide analogs of GPR40 agonist TAK-875. Drug Dev Res 2020; 81:708-715. [PMID: 32359092 DOI: 10.1002/ddr.21675] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 03/25/2020] [Accepted: 04/11/2020] [Indexed: 10/31/2023]
Abstract
TAK-875 (compound 1) was the only GPR40 agonist with promising oral glucose-lowering effect, which entered phase III clinical trials. In previous studies, we successfully synthesized the TAK-875 sulfoxide analog 2, which was further separated to optically pure compounds 3 (S, S, 100.0% de) and 4 (R, S, 100.0% de). In vitro biological evaluation revealed that the sulfoxide analogs 3 and 4 possessed comparable GPR40 agonist activity to TAK-875. Herein, in order to further evaluate the druglikeness of TAK-875 sulfoxide analogs, the pharmacokinetic properties of compounds 2, 3, and 4 in rats were investigated and compared with that of TAK-875. The results showed that sulfoxide (2, 3, and 4) and sulfone (TAK-875) could be converted into each other in different degrees in vivo. Interestingly, compound 3 showed higher drug exposure calculated by the AUC sum of sulfoxide and sulfone in plasma than TAK-875, 2 and 4. In order to further investigate the in vivo glucose-lowering potency of sulfoxide analogs, asymmetric synthesis was carried out and led to two sulfoxides with moderate de values, 5 (S, S, 66.4% de) and 6 (R, S, 71.0% de). The following oral glucose tolerance test (OGTT) in rats showed that 5 (S, S, 66.4% de) had stronger glucose-lowering effect in vivo than 6 (R, S, 71.0% de) and TAK-875, which could be partly rationalized by the superior pharmacokinetic property of sulfoxide 3 (the main component of 5) relative to sulfoxide 4 (the main component of 6) and TAK-875.
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Affiliation(s)
- Yugang Yan
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, China
- School of Medical Engineering, Jining Medical University, Jining, China
| | - Qifu Xu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, China
| | - Chunlong Zhao
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, China
| | - Hang Dong
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, China
| | - Wenfang Xu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, China
| | - Yingjie Zhang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Ji'nan, China
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Teng D, Chen J, Li D, Wu Z, Li W, Tang Y, Liu G. Computational Insights into Molecular Activation and Positive Cooperative Mechanisms of FFAR1 Modulators. J Chem Inf Model 2020; 60:3214-3230. [DOI: 10.1021/acs.jcim.0c00030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Dan Teng
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Jianhui Chen
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Dongping Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Zengrui Wu
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Weihua Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Yun Tang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Guixia Liu
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
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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: 458] [Impact Index Per Article: 91.6] [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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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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12
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Kim CS, Joo SY, Kim IJ, Choi HI, Bae EH, Kim SW, Ma SK. Anti-Apoptotic Effect of G-Protein-Coupled Receptor 40 Activation on Tumor Necrosis Factor-α-Induced Injury of Rat Proximal Tubular Cells. Int J Mol Sci 2019; 20:ijms20143386. [PMID: 31295865 PMCID: PMC6678114 DOI: 10.3390/ijms20143386] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 07/08/2019] [Accepted: 07/08/2019] [Indexed: 11/26/2022] Open
Abstract
G-protein-coupled receptor 40 (GPR40) has an anti-apoptotic effect in pancreatic β-cells. However, its role in renal tubular cell apoptosis remains unclear. To explore the role of GPR40 in renal tubular apoptosis, a two-week unilateral ureteral obstruction (UUO) mouse model was used. The protein expression of GPR40 was decreased, while the Bax/Bcl-2 protein expression ratio, the expression of tumor necrosis factor (TNF)-α mRNA, and angiotensin II type 1 receptor (AT1R) protein were increased in mice with UUO. In vitro, pretreatment of rat proximal tubular (NRK52E) cells with GW9508, a GPR40 agonist, attenuated the decreased cell viability, increased the Bax/Bcl-2 protein expression ratio, increased protein expression of cleaved caspase-3 and activated the nuclear translocation of nuclear factor-κB (NF-κB) p65 subunit induced by TNF-α treatment. TNF-α treatment significantly increased the expression of AT1R protein and the generation of reactive oxygen species (ROS), whereas GW9508 treatment markedly reversed these effects. Pretreatment with GW1100, a GPR40 antagonist, or silencing of GPR40 in NRK52E cells promoted the increased expression of the cleaved caspase-3 protein by TNF-α treatment. Our results demonstrate that decreased expression of GPR40 is associated with apoptosis via TNF-α and AT1R in the ureteral obstructed kidney. The activation of GPR40 attenuates TNF-α-induced apoptosis by inhibiting AT1R expression and ROS generation through regulation of the NF-κB signaling pathway.
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Affiliation(s)
- Chang Seong Kim
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju 61469, Korea
| | - Soo Yeon Joo
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju 61469, Korea
| | - In Jin Kim
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju 61469, Korea
| | - Hoon-In Choi
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju 61469, Korea
| | - Eun Hui Bae
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju 61469, Korea
| | - Soo Wan Kim
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju 61469, Korea.
| | - Seong Kwon Ma
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju 61469, Korea.
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Falomir-Lockhart LJ, Cavazzutti GF, Giménez E, Toscani AM. Fatty Acid Signaling Mechanisms in Neural Cells: Fatty Acid Receptors. Front Cell Neurosci 2019; 13:162. [PMID: 31105530 PMCID: PMC6491900 DOI: 10.3389/fncel.2019.00162] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 04/08/2019] [Indexed: 12/15/2022] Open
Abstract
Fatty acids (FAs) are typically associated with structural and metabolic roles, as they can be stored as triglycerides, degraded by β-oxidation or used in phospholipids’ synthesis, the main components of biological membranes. It has been shown that these lipids exhibit also regulatory functions in different cell types. FAs can serve as secondary messengers, as well as modulators of enzymatic activities and substrates for cytokines synthesis. More recently, it has been documented a direct activity of free FAs as ligands of membrane, cytosolic, and nuclear receptors, and cumulative evidence has emerged, demonstrating its participation in a wide range of physiological and pathological conditions. It has been long known that the central nervous system is enriched with poly-unsaturated FAs, such as arachidonic (C20:4ω-6) or docosohexaenoic (C22:6ω-3) acids. These lipids participate in the regulation of membrane fluidity, axonal growth, development, memory, and inflammatory response. Furthermore, a whole family of low molecular weight compounds derived from FAs has also gained special attention as the natural ligands for cannabinoid receptors or key cytokines involved in inflammation, largely expanding the role of FAs as precursors of signaling molecules. Nutritional deficiencies, and alterations in lipid metabolism and lipid signaling have been associated with developmental and cognitive problems, as well as with neurodegenerative diseases. The molecular mechanism behind these effects still remains elusive. But in the last two decades, different families of proteins have been characterized as receptors mediating FAs signaling. This review focuses on different receptors sensing and transducing free FAs signals in neural cells: (1) membrane receptors of the family of G Protein Coupled Receptors known as Free Fatty Acid Receptors (FFARs); (2) cytosolic transport Fatty Acid-Binding Proteins (FABPs); and (3) transcription factors Peroxisome Proliferator-Activated Receptors (PPARs). We discuss how these proteins modulate and mediate direct regulatory functions of free FAs in neural cells. Finally, we briefly discuss the advantages of evaluating them as potential targets for drug design in order to manipulate lipid signaling. A thorough characterization of lipid receptors of the nervous system could provide a framework for a better understanding of their roles in neurophysiology and, potentially, help for the development of novel drugs against aging and neurodegenerative processes.
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Affiliation(s)
- Lisandro Jorge Falomir-Lockhart
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), Centro Científico Tecnológico - La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), La Plata, Argentina.,Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP), La Plata, Argentina
| | - Gian Franco Cavazzutti
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), Centro Científico Tecnológico - La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), La Plata, Argentina.,Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP), La Plata, Argentina
| | - Ezequiel Giménez
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), Centro Científico Tecnológico - La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), La Plata, Argentina.,Facultad de Ciencias Médicas, Universidad Nacional de La Plata (UNLP), La Plata, Argentina
| | - Andrés Martín Toscani
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), Centro Científico Tecnológico - La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), La Plata, Argentina.,Facultad de Ciencias Médicas, Universidad Nacional de La Plata (UNLP), La Plata, Argentina
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14
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Wold EA, Chen J, Cunningham KA, Zhou J. Allosteric Modulation of Class A GPCRs: Targets, Agents, and Emerging Concepts. J Med Chem 2019; 62:88-127. [PMID: 30106578 PMCID: PMC6556150 DOI: 10.1021/acs.jmedchem.8b00875] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
G-protein-coupled receptors (GPCRs) have been tractable drug targets for decades with over one-third of currently marketed drugs targeting GPCRs. Of these, the class A GPCR superfamily is highly represented, and continued drug discovery for this family of receptors may provide novel therapeutics for a vast range of diseases. GPCR allosteric modulation is an innovative targeting approach that broadens the available small molecule toolbox and is proving to be a viable drug discovery strategy, as evidenced by recent FDA approvals and clinical trials. Numerous class A GPCR allosteric modulators have been discovered recently, and emerging trends such as the availability of GPCR crystal structures, diverse functional assays, and structure-based computational approaches are improving optimization and development. This Perspective provides an update on allosterically targeted class A GPCRs and their disease indications and the medicinal chemistry approaches toward novel allosteric modulators and highlights emerging trends and opportunities in the field.
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Affiliation(s)
- Eric A. Wold
- Department of Pharmacology and Toxicology, Chemical Biology Program, University of Texas Medical Branch, Galveston, Texas 77555, United States
- Department of Pharmacology and Toxicology, Center for Addiction Research, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Jianping Chen
- Department of Pharmacology and Toxicology, Chemical Biology Program, University of Texas Medical Branch, Galveston, Texas 77555, United States
- Department of Pharmacology and Toxicology, Center for Addiction Research, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Kathryn A. Cunningham
- Department of Pharmacology and Toxicology, Chemical Biology Program, University of Texas Medical Branch, Galveston, Texas 77555, United States
- Department of Pharmacology and Toxicology, Center for Addiction Research, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Jia Zhou
- Department of Pharmacology and Toxicology, Chemical Biology Program, University of Texas Medical Branch, Galveston, Texas 77555, United States
- Department of Pharmacology and Toxicology, Center for Addiction Research, University of Texas Medical Branch, Galveston, Texas 77555, United States
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15
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Lu S, Zhang J. Small Molecule Allosteric Modulators of G-Protein-Coupled Receptors: Drug–Target Interactions. J Med Chem 2018; 62:24-45. [DOI: 10.1021/acs.jmedchem.7b01844] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Shaoyong Lu
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025, China
| | - Jian Zhang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025, China
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16
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Rodrigues DA, Pinheiro PDSM, Ferreira TTDSC, Thota S, Fraga CAM. Structural basis for the agonist action at free fatty acid receptor 1 (FFA1R or GPR40). Chem Biol Drug Des 2017; 91:668-680. [DOI: 10.1111/cbdd.13131] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 09/02/2017] [Accepted: 10/14/2017] [Indexed: 01/24/2023]
Affiliation(s)
- Daniel Alencar Rodrigues
- Laboratório de Avaliação e Síntese de Substâncias Bioativas (LASSBio); Instituto de Ciências Biomédicas; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
- Programa de Pós-Graduação em Química; Instituto de Química; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
| | - Pedro de Sena Murteira Pinheiro
- Laboratório de Avaliação e Síntese de Substâncias Bioativas (LASSBio); Instituto de Ciências Biomédicas; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
- Programa de Pós-Graduação em Farmacologia e Química Medicinal; Instituto de Ciências Biomédicas; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
| | - Thayssa Tavares da Silva Cunha Ferreira
- Laboratório de Avaliação e Síntese de Substâncias Bioativas (LASSBio); Instituto de Ciências Biomédicas; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
- Programa de Pós-Graduação em Farmacologia e Química Medicinal; Instituto de Ciências Biomédicas; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
| | - Sreekanth Thota
- Laboratório de Avaliação e Síntese de Substâncias Bioativas (LASSBio); Instituto de Ciências Biomédicas; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
- National Institute for Science and Technology on Innovation on Neglected Diseases (INCT/IDN); Center for Technological Development in Health (CDTS); Fundação Oswaldo Cruz - Ministério da Saúde; Rio de Janeiro RJ Brazil
| | - Carlos Alberto Manssour Fraga
- Laboratório de Avaliação e Síntese de Substâncias Bioativas (LASSBio); Instituto de Ciências Biomédicas; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
- Programa de Pós-Graduação em Química; Instituto de Química; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
- Programa de Pós-Graduação em Farmacologia e Química Medicinal; Instituto de Ciências Biomédicas; Universidade Federal do Rio de Janeiro; Rio de Janeiro RJ Brazil
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17
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Arodola OA, Soliman MES. Quantum mechanics implementation in drug-design workflows: does it really help? Drug Des Devel Ther 2017; 11:2551-2564. [PMID: 28919707 PMCID: PMC5587087 DOI: 10.2147/dddt.s126344] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The pharmaceutical industry is progressively operating in an era where development costs are constantly under pressure, higher percentages of drugs are demanded, and the drug-discovery process is a trial-and-error run. The profit that flows in with the discovery of new drugs has always been the motivation for the industry to keep up the pace and keep abreast with the endless demand for medicines. The process of finding a molecule that binds to the target protein using in silico tools has made computational chemistry a valuable tool in drug discovery in both academic research and pharmaceutical industry. However, the complexity of many protein-ligand interactions challenges the accuracy and efficiency of the commonly used empirical methods. The usefulness of quantum mechanics (QM) in drug-protein interaction cannot be overemphasized; however, this approach has little significance in some empirical methods. In this review, we discuss recent developments in, and application of, QM to medically relevant biomolecules. We critically discuss the different types of QM-based methods and their proposed application to incorporating them into drug-design and -discovery workflows while trying to answer a critical question: are QM-based methods of real help in drug-design and -discovery research and industry?
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Affiliation(s)
- Olayide A Arodola
- Department of Pharmaceutical Chemistry, University of KwaZulu-Natal, Durban, South Africa
| | - Mahmoud ES Soliman
- Department of Pharmaceutical Chemistry, University of KwaZulu-Natal, Durban, South Africa
- Department of Pharmaceutical Organic Chemistry, Faculty of Pharmacy, Zagazig University, Egypt
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18
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Li Z, Xu X, Huang W, Qian H. Free Fatty Acid Receptor 1 (FFAR1) as an Emerging Therapeutic Target for Type 2 Diabetes Mellitus: Recent Progress and Prevailing Challenges. Med Res Rev 2017; 38:381-425. [DOI: 10.1002/med.21441] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 01/23/2017] [Accepted: 02/14/2017] [Indexed: 12/19/2022]
Affiliation(s)
- Zheng Li
- Center of Drug Discovery, State Key Laboratory of Natural Medicines; China Pharmaceutical University; 24 Tongjiaxiang Nanjing 210009 P.R. China
| | - Xue Xu
- Key Laboratory of Drug Quality Control and Pharmacovigilance; China Pharmaceutical University; 24 Tongjiaxiang Nanjing 210009 P.R. China
| | - Wenlong Huang
- Center of Drug Discovery, State Key Laboratory of Natural Medicines; China Pharmaceutical University; 24 Tongjiaxiang Nanjing 210009 P.R. China
- Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease; China Pharmaceutical University; 24 Tongjiaxiang Nanjing 210009 P.R. China
| | - Hai Qian
- Center of Drug Discovery, State Key Laboratory of Natural Medicines; China Pharmaceutical University; 24 Tongjiaxiang Nanjing 210009 P.R. China
- Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease; China Pharmaceutical University; 24 Tongjiaxiang Nanjing 210009 P.R. China
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19
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Li H, Huang Q, Chen C, Xu B, Wang HY, Long YQ. Discovery of Potent and Orally Bioavailable GPR40 Full Agonists Bearing Thiophen-2-ylpropanoic Acid Scaffold. J Med Chem 2017; 60:2697-2717. [DOI: 10.1021/acs.jmedchem.6b01357] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- He Li
- CAS
Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qi Huang
- CAS
Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Cheng Chen
- CAS
Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
- Department
of Chemistry, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Bin Xu
- Department
of Chemistry, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - He-Yao Wang
- CAS
Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Ya-Qiu Long
- CAS
Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
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20
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Ngo T, Kufareva I, Coleman JL, Graham RM, Abagyan R, Smith NJ. Identifying ligands at orphan GPCRs: current status using structure-based approaches. Br J Pharmacol 2016; 173:2934-51. [PMID: 26837045 PMCID: PMC5341249 DOI: 10.1111/bph.13452] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 11/18/2015] [Accepted: 01/29/2016] [Indexed: 12/26/2022] Open
Abstract
GPCRs are the most successful pharmaceutical targets in history. Nevertheless, the pharmacology of many GPCRs remains inaccessible as their endogenous or exogenous modulators have not been discovered. Tools that explore the physiological functions and pharmacological potential of these 'orphan' GPCRs, whether they are endogenous and/or surrogate ligands, are therefore of paramount importance. Rates of receptor deorphanization determined by traditional reverse pharmacology methods have slowed, indicating a need for the development of more sophisticated and efficient ligand screening approaches. Here, we discuss the use of structure-based ligand discovery approaches to identify small molecule modulators for exploring the function of orphan GPCRs. These studies have been buoyed by the growing number of GPCR crystal structures solved in the past decade, providing a broad range of template structures for homology modelling of orphans. This review discusses the methods used to establish the appropriate signalling assays to test orphan receptor activity and provides current examples of structure-based methods used to identify ligands of orphan GPCRs. Linked Articles This article is part of a themed section on Molecular Pharmacology of G Protein-Coupled Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.20/issuetoc.
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Affiliation(s)
- Tony Ngo
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia
- St. Vincent's Clinical School, University of New South Wales, Darlinghurst, NSW, Australia
| | - Irina Kufareva
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, CA, USA
| | - James Lj Coleman
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia
- St. Vincent's Clinical School, University of New South Wales, Darlinghurst, NSW, Australia
| | - Robert M Graham
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia
- St. Vincent's Clinical School, University of New South Wales, Darlinghurst, NSW, Australia
| | - Ruben Abagyan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, CA, USA
| | - Nicola J Smith
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia.
- St. Vincent's Clinical School, University of New South Wales, Darlinghurst, NSW, Australia.
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21
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Milligan G, Shimpukade B, Ulven T, Hudson BD. Complex Pharmacology of Free Fatty Acid Receptors. Chem Rev 2016; 117:67-110. [PMID: 27299848 DOI: 10.1021/acs.chemrev.6b00056] [Citation(s) in RCA: 185] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
G protein-coupled receptors (GPCRs) are historically the most successful family of drug targets. In recent times it has become clear that the pharmacology of these receptors is far more complex than previously imagined. Understanding of the pharmacological regulation of GPCRs now extends beyond simple competitive agonism or antagonism by ligands interacting with the orthosteric binding site of the receptor to incorporate concepts of allosteric agonism, allosteric modulation, signaling bias, constitutive activity, and inverse agonism. Herein, we consider how evolving concepts of GPCR pharmacology have shaped understanding of the complex pharmacology of receptors that recognize and are activated by nonesterified or "free" fatty acids (FFAs). The FFA family of receptors is a recently deorphanized set of GPCRs, the members of which are now receiving substantial interest as novel targets for the treatment of metabolic and inflammatory diseases. Further understanding of the complex pharmacology of these receptors will be critical to unlocking their ultimate therapeutic potential.
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Affiliation(s)
- 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, United Kingdom
| | - Bharat Shimpukade
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense M, Denmark
| | - Trond Ulven
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense M, Denmark
| | - Brian D Hudson
- 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, United Kingdom
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22
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Tikhonova IG, Poerio E. Free fatty acid receptors: structural models and elucidation of ligand binding interactions. BMC STRUCTURAL BIOLOGY 2015; 15:16. [PMID: 26346819 PMCID: PMC4561419 DOI: 10.1186/s12900-015-0044-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 08/26/2015] [Indexed: 12/14/2022]
Abstract
Background The free fatty acid receptors (FFAs), including FFA1 (orphan name: GPR40), FFA2 (GPR43) and FFA3 (GPR41) are G protein-coupled receptors (GPCRs) involved in energy and metabolic homeostasis. Understanding the structural basis of ligand binding at FFAs is an essential step toward designing potent and selective small molecule modulators. Results We analyse earlier homology models of FFAs in light of the newly published FFA1 crystal structure co-crystallized with TAK-875, an ago-allosteric ligand, focusing on the architecture of the extracellular binding cavity and agonist-receptor interactions. The previous low-resolution homology models of FFAs were helpful in highlighting the location of the ligand binding site and the key residues for ligand anchoring. However, homology models were not accurate in establishing the nature of all ligand-receptor contacts and the precise ligand-binding mode. From analysis of structural models and mutagenesis, it appears that the position of helices 3, 4 and 5 is crucial in ligand docking. The FFA1-based homology models of FFA2 and FFA3 were constructed and used to compare the FFA subtypes. From docking studies we propose an alternative binding mode for orthosteric agonists at FFA1 and FFA2, involving the interhelical space between helices 4 and 5. This binding mode can explain mutagenesis results for residues at positions 4.56 and 5.42. The novel FFAs structural models highlight higher aromaticity of the FFA2 binding cavity and higher hydrophilicity of the FFA3 binding cavity. The role of the residues at the second extracellular loop used in mutagenesis is reanalysed. The third positively-charged residue in the binding cavity of FFAs, located in helix 2, is identified and predicted to coordinate allosteric modulators. Conclusions The novel structural models of FFAs provide information on specific modes of ligand binding at FFA subtypes and new suggestions for mutagenesis and ligand modification, guiding the development of novel orthosteric and allosteric chemical probes to validate the importance of FFAs in metabolic and inflammatory conditions. Using our FFA homology modelling experience, a strategy to model a GPCR, which is phylogenetically distant from GPCRs with the available crystal structures, is discussed. Electronic supplementary material The online version of this article (doi:10.1186/s12900-015-0044-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Irina G Tikhonova
- Molecular Therapeutics, School of Pharmacy, Medical Biology Centre, Queen's University Belfast, Belfast, BT9 7BL, Northern Ireland, UK.
| | - Elena Poerio
- Molecular Therapeutics, School of Pharmacy, Medical Biology Centre, Queen's University Belfast, Belfast, BT9 7BL, Northern Ireland, UK.
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23
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Mancini AD, Poitout V. GPR40 agonists for the treatment of type 2 diabetes: life after 'TAKing' a hit. Diabetes Obes Metab 2015; 17:622-9. [PMID: 25604916 DOI: 10.1111/dom.12442] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 01/13/2015] [Accepted: 01/17/2015] [Indexed: 12/17/2022]
Abstract
The free fatty acid receptor GPR40 has been proposed as a potential target for type 2 diabetes (T2D) pharmacotherapy. This idea has been validated in both preclinical and clinical studies, in which activation of GPR40 was shown to improve glycaemic control by stimulating glucose-dependent insulin secretion; however, the recent termination of phase III clinical trials using the GPR40 agonist TAK-875 (fasiglifam) has raised important questions regarding the long-term safety and viability of targeting GPR40 and, more specifically, about our understanding of this receptor's basic biology. In the present review, we provide a summary of established and novel concepts related to GPR40's pharmacobiology and discuss the current status and future outlook for GPR40-based drug development for the treatment of T2D.
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Affiliation(s)
- A D Mancini
- Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC, Canada
- Department of Medicine, Université de Montréal, Montréal, QC, Canada
| | - V Poitout
- Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC, Canada
- Department of Medicine, Université de Montréal, Montréal, QC, Canada
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24
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Milligan G, Alvarez-Curto E, Watterson KR, Ulven T, Hudson BD. Characterizing pharmacological ligands to study the long-chain fatty acid receptors GPR40/FFA1 and GPR120/FFA4. Br J Pharmacol 2015; 172:3254-65. [PMID: 25131623 DOI: 10.1111/bph.12879] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 08/05/2014] [Accepted: 08/11/2014] [Indexed: 02/06/2023] Open
Abstract
The free fatty acid receptors (FFA) 1 (previously designated GPR40) and FFA4 (previously GPR120) are two GPCRs activated by saturated and unsaturated longer-chain free fatty acids. With expression patterns and functions anticipated to directly or indirectly promote insulin secretion, provide homeostatic control of blood glucose and improve tissue insulin sensitivity, both receptors are being studied as potential therapeutic targets for the control of type 2 diabetes. Furthermore, genetic and systems biology studies in both humans and mouse models link FFA4 receptors to diabetes and obesity. Although activated by the same group of free fatty acids, FFA1 and FFA4 receptors are not closely related and, while the basis of recognition of fatty acids by FFA1 receptors is similar to that of the short-chain fatty acid receptors FFA2 and FFA3, the amino acid residues involved in endogenous ligand recognition by FFA4 receptors are more akin to those of the sphingosine 1 phosphate receptor S1P1 . Screening and subsequent medicinal chemistry programmes have developed a number of FFA1 receptor selective agonists that are effective in promoting insulin secretion in a glucose concentration-dependent manner, and in lowering blood glucose levels. However, the recent termination of Phase III clinical trials employing TAK-875/fasiglifam has caused a setback and raises important questions over the exact nature and mechanistic causes of the problems. Progress in the identification and development of highly FFA4 receptor-selective pharmacological tools has been less rapid and several issues remain to be clarified to fully validate this receptor as a therapeutic target. Despite this, the ongoing development of a range of novel ligands offers great opportunities to further unravel the contributions of these receptors.
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Affiliation(s)
- G Milligan
- Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - E Alvarez-Curto
- Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - K R Watterson
- Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - T Ulven
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense, Denmark
| | - B D Hudson
- Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
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25
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Hudson BD, Shimpukade B, Milligan G, Ulven T. The molecular basis of ligand interaction at free fatty acid receptor 4 (FFA4/GPR120). J Biol Chem 2014; 289:20345-58. [PMID: 24860101 PMCID: PMC4106347 DOI: 10.1074/jbc.m114.561449] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The long-chain fatty acid receptor FFA4 (previously GPR120) is receiving substantial interest as a novel target for the treatment of metabolic and inflammatory disease. This study examines for the first time the detailed mode of binding of both long-chain fatty acid and synthetic agonist ligands at FFA4 by integrating molecular modeling, receptor mutagenesis, and ligand structure-activity relationship approaches in an iterative format. In doing so, residues required for binding of fatty acid and synthetic agonists to FFA4 have been identified. This has allowed for the refinement of a well validated model of the mode of ligand-FFA4 interaction that will be invaluable in the identification of novel ligands and the future development of this receptor as a therapeutic target. The model reliably predicted the effects of substituent variations on agonist potency, and it was also able to predict the qualitative effect of binding site mutations in the majority of cases.
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Affiliation(s)
- Brian D Hudson
- From the Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom and
| | - Bharat Shimpukade
- the Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Graeme Milligan
- From the Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom and
| | - Trond Ulven
- the Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
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26
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Huang H, Dai MH, Tao YX. Physiology and Therapeutics of the Free Fatty Acid Receptor GPR40. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2014; 121:67-94. [DOI: 10.1016/b978-0-12-800101-1.00003-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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27
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Yao S, Lu T, Zhou Z, Liu H, Yuan H, Ran T, Lu S, Zhang Y, Ke Z, Xu J, Xiong X, Chen Y. An efficient multistep ligand-based virtual screening approach for GPR40 agonists. Mol Divers 2013; 18:183-93. [PMID: 24307222 DOI: 10.1007/s11030-013-9493-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 11/11/2013] [Indexed: 10/25/2022]
Abstract
G protein-coupled receptor 40/free fatty acid receptor 1 (GPR40/FFAR1) is a member of the GPCR superfamily, and GPR40 agonists have therapeutic potential for type 2 diabetes. With the crystal structure of GPR40 currently unavailable, various ligand-based virtual screening approaches can be applied to identify novel agonists of GPR40. It is known that each ligand-based method has its own advantages and limitations. To improve the efficiency of individual ligand-based methods, an efficient multistep ligand-based virtual screening approach is presented in this study, including the pharmacophore-based screening, physicochemical property filtering, protein-ligand interaction fingerprint similarity analysis, and 2D-fingerprint structural similarity search. A focused decoy library was generated and used to evaluate the efficiency of this virtual screening protocol. This multistep workflow not only significantly improved the hit rate compared with each individual ligand-based method, but also identified diverse known actives from decoys. This protocol may serve as an efficient virtual screening tool for the targets without crystal structures available to discover novel active compounds.
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Affiliation(s)
- Sihui Yao
- Laboratory of Molecular Design and Drug Discovery, School of Basic Science, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing, 210009, China
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Takeuchi M, Hirasawa A, Hara T, Kimura I, Hirano T, Suzuki T, Miyata N, Awaji T, Ishiguro M, Tsujimoto G. FFA1-selective agonistic activity based on docking simulation using FFA1 and GPR120 homology models. Br J Pharmacol 2013; 168:1570-83. [PMID: 22639973 DOI: 10.1111/j.1476-5381.2012.02052.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE The free fatty acid FFA1 receptor and GPR120 are GPCRs whose endogenous ligands are medium- and long-chain FFAs, and they are important in regulating insulin and GLP-1 secretion respectively. Given that the ligands of FFA1 receptor and GPR120 have similar properties, selective pharmacological tools are required to study their functions further. EXPERIMENTAL APPROACH We used a docking simulation approach using homology models for each receptor. Biological activity was assessed by phosphorylation of ERK and elevation of intracellular calcium ([Ca(2+) ]i ) in cells transfected with FFA1 receptor or GPR120. Insulin secretion from murine pancreatic beta cells (MIN6) was also measured. KEY RESULTS Calculated hydrogen bonding energies between a series of synthetic carboxylic acid compounds and the homology models of the FFA1 receptor and GPR120, using docking simulations, correlated well with the effects of the compounds on ERK phosphorylation in transfected cells (R(2) = 0.65 for FFA1 receptor and 0.76 for GPR120). NCG75, the compound with the highest predicted selectivity for FFA1 receptors from this structure-activity relationship analysis, activated ERK and increased [Ca(2+) ]i as potently as the known FFA1 receptor-selective agonist, Compound 1. Site-directed mutagenesis analysis based on the docking simulation showed that different amino acid residues were important for the recognition and activation by FFA1 receptor agonists. Moreover, NCG75 strongly induced ERK and [Ca(2+) ]i responses, and promoted insulin secretion from MIN6 cells, which express endogenous FFA1 receptors. CONCLUSION AND IMPLICATIONS A docking simulation approach using FFA1 receptor and GPR120 homology models could be useful in predicting FFA1 receptor-selective agonists.
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Affiliation(s)
- Masato Takeuchi
- Department of Genomic Drug Discovery Science, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
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29
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Soriano-Ursúa MA, Trujillo-Ferrara JG, Correa-Basurto J, Vilar S. Recent structural advances of β1 and β2 adrenoceptors yield keys for ligand recognition and drug design. J Med Chem 2013; 56:8207-23. [PMID: 23862978 DOI: 10.1021/jm400471z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Because they represent attractive drug targets, adrenoceptors have been widely studied. Recent progress in structural data of β-adrenoceptors allows us to understand and predict key interactions in ligand recognition and receptor activation. Nevertheless, an important aspect of this process has only begun to be explored: the stabilization of a conformational state of these receptors upon contact with a ligand and the capacity of a ligand to influence receptor conformation through allosteric modulation, biased signaling, and selectivity. The aim of the present Perspective is to identify the well-defined orthosteric binding site and possible allosteric sites and to analyze the importance of the ligand-receptor interaction in the stabilization of certain receptor conformations. For this purpose, we have reviewed recent advances made through the use of X-ray data from ligand-β-adrenoceptor (including ADRB1 and ADRB2) crystal structures. Most importantly, implications in the medicinal chemistry field are explored in relation to drug design.
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Affiliation(s)
- Marvin A Soriano-Ursúa
- Departments of Biochemistry and Physiology, Laboratory of Molecular Modeling and Bioinformatics, Postgraduate Research Section, Escuela Superior de Medicina, Instituto Politécnico Nacional , Plan de San Luis y Dı́az Mirón s/n, Mexico City, 11340, Mexico
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30
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Offermanns S. Free fatty acid (FFA) and hydroxy carboxylic acid (HCA) receptors. Annu Rev Pharmacol Toxicol 2013; 54:407-34. [PMID: 24160702 DOI: 10.1146/annurev-pharmtox-011613-135945] [Citation(s) in RCA: 118] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Saturated and unsaturated free fatty acids (FFAs), as well as hydroxy carboxylic acids (HCAs) such as lactate and ketone bodies, are carriers of metabolic energy, precursors of biological mediators, and components of biological structures. However, they are also able to exert cellular effects through G protein-coupled receptors named FFA1-FFA4 and HCA1-HCA3. Work during the past decade has shown that these receptors are widely expressed in the human body and regulate the metabolic, endocrine, immune and other systems to maintain homeostasis under changing dietary conditions. The development of genetic mouse models and the generation of synthetic ligands of individual FFA and HCA receptors have been instrumental in identifying cellular and biological functions of these receptors. These studies have produced strong evidence that several FFA and HCA receptors can be targets for the prevention and treatment of various diseases, including type 2 diabetes mellitus, obesity, and inflammation.
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Affiliation(s)
- Stefan Offermanns
- Department of Pharmacology, Max-Planck-Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany and Medical Faculty, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany;
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31
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Yabuki C, Komatsu H, Tsujihata Y, Maeda R, Ito R, Matsuda-Nagasumi K, Sakuma K, Miyawaki K, Kikuchi N, Takeuchi K, Habata Y, Mori M. A novel antidiabetic drug, fasiglifam/TAK-875, acts as an ago-allosteric modulator of FFAR1. PLoS One 2013; 8:e76280. [PMID: 24130766 PMCID: PMC3794927 DOI: 10.1371/journal.pone.0076280] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 08/22/2013] [Indexed: 01/23/2023] Open
Abstract
Selective free fatty acid receptor 1 (FFAR1)/GPR40 agonist fasiglifam (TAK-875), an antidiabetic drug under phase 3 development, potentiates insulin secretion in a glucose-dependent manner by activating FFAR1 expressed in pancreatic β cells. Although fasiglifam significantly improved glycemic control in type 2 diabetes patients with a minimum risk of hypoglycemia in a phase 2 study, the precise mechanisms of its potent pharmacological effects are not fully understood. Here we demonstrate that fasiglifam acts as an ago-allosteric modulator with a partial agonistic activity for FFAR1. In both Ca2+ influx and insulin secretion assays using cell lines and mouse islets, fasiglifam showed positive cooperativity with the FFAR1 ligand γ-linolenic acid (γ-LA). Augmentation of glucose-induced insulin secretion by fasiglifam, γ-LA, or their combination was completely abolished in pancreatic islets of FFAR1-knockout mice. In diabetic rats, the insulinotropic effect of fasiglifam was suppressed by pharmacological reduction of plasma free fatty acid (FFA) levels using a lipolysis inhibitor, suggesting that fasiglifam potentiates insulin release in conjunction with plasma FFAs in vivo. Point mutations of FFAR1 differentially affected Ca2+ influx activities of fasiglifam and γ-LA, further indicating that these agonists may bind to distinct binding sites. Our results strongly suggest that fasiglifam is an ago-allosteric modulator of FFAR1 that exerts its effects by acting cooperatively with endogenous plasma FFAs in human patients as well as diabetic animals. These findings contribute to our understanding of fasiglifam as an attractive antidiabetic drug with a novel mechanism of action.
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Affiliation(s)
- Chiori Yabuki
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
- * E-mail:
| | - Hidetoshi Komatsu
- Central Nervous System Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Yoshiyuki Tsujihata
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Risa Maeda
- Central Nervous System Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Ryo Ito
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Kae Matsuda-Nagasumi
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Kensuke Sakuma
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Kazumasa Miyawaki
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Naoya Kikuchi
- Central Nervous System Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Koji Takeuchi
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Yugo Habata
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Masaaki Mori
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
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32
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Hudson BD, Shimpukade B, Mackenzie AE, Butcher AJ, Pediani JD, Christiansen E, Heathcote H, Tobin AB, Ulven T, Milligan G. The pharmacology of TUG-891, a potent and selective agonist of the free fatty acid receptor 4 (FFA4/GPR120), demonstrates both potential opportunity and possible challenges to therapeutic agonism. Mol Pharmacol 2013; 84:710-25. [PMID: 23979972 DOI: 10.1124/mol.113.087783] [Citation(s) in RCA: 156] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
TUG-891 [3-(4-((4-fluoro-4'-methyl-[1,1'-biphenyl]-2-yl)methoxy)phenyl)propanoic acid] was recently described as a potent and selective agonist for the long chain free fatty acid (LCFA) receptor 4 (FFA4; previously G protein-coupled receptor 120, or GPR120). Herein, we have used TUG-891 to further define the function of FFA4 and used this compound in proof of principle studies to indicate the therapeutic potential of this receptor. TUG-891 displayed similar signaling properties to the LCFA α-linolenic acid at human FFA4 across various assay end points, including stimulation of Ca²⁺ mobilization, β-arrestin-1 and β-arrestin-2 recruitment, and extracellular signal-regulated kinase phosphorylation. Activation of human FFA4 by TUG-891 also resulted in rapid phosphorylation and internalization of the receptor. While these latter events were associated with desensitization of the FFA4 signaling response, removal of TUG-891 allowed both rapid recycling of FFA4 back to the cell surface and resensitization of the FFA4 Ca²⁺ signaling response. TUG-891 was also a potent agonist of mouse FFA4, but it showed only limited selectivity over mouse FFA1, complicating its use in vivo in this species. Pharmacologic dissection of responses to TUG-891 in model murine cell systems indicated that activation of FFA4 was able to mimic many potentially beneficial therapeutic properties previously reported for LCFAs, including stimulating glucagon-like peptide-1 secretion from enteroendocrine cells, enhancing glucose uptake in 3T3-L1 adipocytes, and inhibiting release of proinflammatory mediators from RAW264.7 macrophages, which suggests promise for FFA4 as a therapeutic target for type 2 diabetes and obesity. Together, these results demonstrate both potential but also significant challenges that still need to be overcome to therapeutically target FFA4.
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Affiliation(s)
- Brian D Hudson
- Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom (B.D.H., A.E.M., J.D.P., H.H., G.M.); Department of Physics, Chemistry, and Pharmacy, University of Southern Denmark, Odense, Denmark (B.S., E.C., T.U.); and MRC Toxicology Unit, University of Leicester, Leicester, United Kingdom (A.J.B., A.B.T.)
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33
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Mancini AD, Poitout V. The fatty acid receptor FFA1/GPR40 a decade later: how much do we know? Trends Endocrinol Metab 2013; 24:398-407. [PMID: 23631851 DOI: 10.1016/j.tem.2013.03.003] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 03/18/2013] [Accepted: 03/21/2013] [Indexed: 11/18/2022]
Abstract
Glucose homeostasis requires the highly coordinated regulation of insulin secretion by pancreatic β cells. This is primarily mediated by glucose itself, but other nutrients, including free fatty acids (FFAs), potentiate the insulinotropic capacity of glucose. A decade ago, the seven-transmembrane domain receptor (7TMR) GPR40 was demonstrated to be predominantly expressed in β cells and activated by long-chain FFAs. This discovery added a new dimension to our understanding of FFA-mediated control of glucose homeostasis. Furthermore, GPR40 has drawn considerable interest as a novel therapeutic target to enhance insulin secretion in type 2 diabetes. However, our understanding of the biology of GPR40 remains incomplete and its physiological role controversial. Here we summarize the current state of knowledge and emerging concepts regarding the role of GPR40 in regulating glucose homeostasis.
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Affiliation(s)
- Arturo D Mancini
- Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Department of Medicine, Université de Montréal, Montréal, QC, Canada
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34
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Urban C, Hamacher A, Partke HJ, Roden M, Schinner S, Christiansen E, Due-Hansen ME, Ulven T, Gohlke H, Kassack MU. In vitro and mouse in vivo characterization of the potent free fatty acid 1 receptor agonist TUG-469. Naunyn Schmiedebergs Arch Pharmacol 2013; 386:1021-30. [PMID: 23861168 DOI: 10.1007/s00210-013-0899-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Accepted: 06/17/2013] [Indexed: 10/26/2022]
Abstract
Activation of the G protein-coupled free fatty acid receptor 1 (FFA1; formerly known as GPR40) leads to an enhancement of glucose-stimulated insulin secretion from pancreatic β-cells. TUG-469 has previously been reported as a potent FFA1 agonist. This study was performed to confirm the higher in vitro potency of TUG-469 compared to the reference FFA1 agonist GW9508 and to prove in vivo activity in a pre-diabetic mouse model. The in vitro pharmacology of TUG-469 was studied using Ca(2+)-, cAMP-, and impedance-based assays at recombinant FFA1 and free fatty acid receptor 4, formerly known as GPR120 (FFA4) expressing 1321N1 cells and the rat insulinoma cell line INS-1. Furthermore, we investigated the systemic effect of TUG-469 on glucose tolerance in pre-diabetic New Zealand obese (NZO) mice performing a glucose tolerance test after intraperitoneal administration of 5 mg/kg TUG-469. In comparison to GW9508, TUG-469 showed a 1.7- to 3.0-times higher potency in vitro at 1321N1 cells recombinantly expressing FFA1. Both compounds increased insulin secretion from rat insulinoma INS-1 cells. TUG-469 is > 200-fold selective for FFA1 over FFA4. Finally, a single dose of 5 mg/kg TUG-469 significantly improved glucose tolerance in pre-diabetic NZO mice. TUG-469 turned out as a promising candidate for further drug development of FFA1 agonists for treatment of type 2 diabetes mellitus.
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Affiliation(s)
- C Urban
- Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-University, Universitätsstr. 1, 40225, Düsseldorf, Germany
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35
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Tokonami N, Morla L, Centeno G, Mordasini D, Ramakrishnan SK, Nikolaeva S, Wagner CA, Bonny O, Houillier P, Doucet A, Firsov D. α-Ketoglutarate regulates acid-base balance through an intrarenal paracrine mechanism. J Clin Invest 2013; 123:3166-71. [PMID: 23934124 DOI: 10.1172/jci67562] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 04/11/2013] [Indexed: 12/11/2022] Open
Abstract
Paracrine communication between different parts of the renal tubule is increasingly recognized as an important determinant of renal function. Previous studies have shown that changes in dietary acid-base load can reverse the direction of apical α-ketoglutarate (αKG) transport in the proximal tubule and Henle's loop from reabsorption (acid load) to secretion (base load). Here we show that the resulting changes in the luminal concentrations of αKG are sensed by the αKG receptor OXGR1 expressed in the type B and non-A-non-B intercalated cells of the connecting tubule (CNT) and the cortical collecting duct (CCD). The addition of 1 mM αKG to the tubular lumen strongly stimulated Cl(-)-dependent HCO(3)(-) secretion and electroneutral transepithelial NaCl reabsorption in microperfused CCDs of wild-type mice but not Oxgr1(-/-) mice. Analysis of alkali-loaded mice revealed a significantly reduced ability of Oxgr1(-/-) mice to maintain acid-base balance. Collectively, these results demonstrate that OXGR1 is involved in the adaptive regulation of HCO(3)(-) secretion and NaCl reabsorption in the CNT/CCD under acid-base stress and establish αKG as a paracrine mediator involved in the functional coordination of the proximal and the distal parts of the renal tubule.
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Affiliation(s)
- Natsuko Tokonami
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
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36
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Zhao YF, Wang L, Zha D, Qiao L, Lu L, Yu J, Qu P, Sun Q, Qiu J, Chen C. GW9508 inhibits insulin secretion by activating ATP-sensitive potassium channels in rat pancreatic β-cells. J Mol Endocrinol 2013; 51:69-77. [PMID: 23628491 DOI: 10.1530/jme-13-0019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
GW9508 is an agonist of G protein-coupled receptor 40 (GPR40) that is expressed in pancreatic β-cells and is reported to regulate insulin secretion. However, the effects of GW9508 on pancreatic β-cells in primary culture have not been well investigated. This study measured the acute effects of GW9508 on insulin secretion from rat pancreatic islets in primary culture, and the insulin secretion-related events such as the changes in membrane potential, ATP-sensitive potassium currents (KATP currents), and intracellular Ca(2+) concentrations ([Ca(2+)]i) of rat islet β-cells were also recorded. GW9508 (10-40 μM) did not influence basal insulin levels at 2 mM glucose, but it (above 20 μM) significantly inhibited 5 and 15 mM glucose-stimulated insulin secretion (GSIS). GW9508 did not inhibit insulin secretion stimulated by tolbutamide, the closer of KATP channels. GW9508 activated KATP channels and blocked the membrane depolarization and the increase in [Ca(2+)]i that were stimulated by glucose. GW9508 itself stimulated a transient increase in [Ca(2+)]i, which was fully blocked by depletion of intracellular Ca(2+) stores with thapsigargin or by inhibition of phospholipase C (PLC) activity with U73122. GW9508-induced activation of KATP channels was only partly inhibited by U73122 treatment. In conclusion, although it stimulates a transient release of Ca(2+) from intracellular Ca(2+) stores via activation of PLC, GW9508 inhibits GSIS by activating KATP channels probably in a distal step to GPR40 activation in rat β-cells.
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Affiliation(s)
- Yu-Feng Zhao
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia
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37
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Hara T, Kimura I, Inoue D, Ichimura A, Hirasawa A. Free Fatty Acid Receptors and Their Role in Regulation of Energy Metabolism. Rev Physiol Biochem Pharmacol 2013; 164:77-116. [DOI: 10.1007/112_2013_13] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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38
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Feng XT, Leng J, Xie Z, Li SL, Zhao W, Tang QL. GPR40: a therapeutic target for mediating insulin secretion (review). Int J Mol Med 2012; 30:1261-6. [PMID: 23023155 DOI: 10.3892/ijmm.2012.1142] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Accepted: 08/26/2012] [Indexed: 11/05/2022] Open
Abstract
G-protein-coupled receptor 40 (GPR40), known as free fatty acid receptor 1, is mainly expressed in pancreatic β-cells and activated by medium- and long-chain fatty acids. Increasing evidence indicates that the activation of GPR40 in cells causes insulin secretion, and GPR40 has become an attractive therapeutic target for type 2 diabetes. Recently, certain novel GPR40 agonists have been identified that regulate glucose-stimulated insulin secretion, leading to the development of new drugs for the treatment of type 2 diabetes. In this review, we focus on progress in the physiological role of GPR40 and potential drugs targeting GPR40 over the past decade.
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Affiliation(s)
- Xiao-Tao Feng
- Guangxi Scientific Experimental Center of Traditional Chinese Medicine, Guangxi University of Chinese Medicine, Nanning, P.R. China
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39
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Lin DCH, Guo Q, Luo J, Zhang J, Nguyen K, Chen M, Tran T, Dransfield PJ, Brown SP, Houze J, Vimolratana M, Jiao XY, Wang Y, Birdsall NJM, Swaminath G. Identification and pharmacological characterization of multiple allosteric binding sites on the free fatty acid 1 receptor. Mol Pharmacol 2012; 82:843-59. [PMID: 22859723 DOI: 10.1124/mol.112.079640] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Activation of FFA1 (GPR40), a member of G protein-coupling receptor family A, is mediated by medium- and long-chain fatty acids and leads to amplification of glucose-stimulated insulin secretion, suggesting a potential role for free fatty acid 1 (FFA1) as a target for type 2 diabetes. It was assumed previously that there is a single binding site for fatty acids and synthetic FFA1 agonists. However, using members of two chemical series of partial and full agonists that have been identified, radioligand binding interaction studies revealed that the full agonists do not bind to the same site as the partial agonists but exhibit positive heterotropic cooperativity. Analysis of functional data reveals positive functional cooperativity between the full agonists and partial agonists in various functional assays (in vitro and ex vivo) and also in vivo. Furthermore, the endogenous fatty acid docosahexaenoic acid (DHA) shows negative or neutral cooperativity with members of both series of agonists in binding assays but displays positive cooperativity in functional assays. Another synthetic agonist is allosteric with members of both agonist series, but apparently competitive with DHA. Therefore, there appear to be three allosterically linked binding sites on FFA1 with agonists specific for each of these sites. Activation of free fatty acid 1 receptor (FFAR1) by each of these agonists is differentially affected by mutations of two arginine residues, previously found to be important for FFAR1 binding and activation. These ligands with their high potencies and strong positive functional cooperativity with endogenous fatty acids, demonstrated in vitro and in vivo, have the potential to deliver therapeutic benefits.
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40
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Smith NJ. Low affinity GPCRs for metabolic intermediates: challenges for pharmacologists. Front Endocrinol (Lausanne) 2012; 3:1. [PMID: 22649402 PMCID: PMC3355937 DOI: 10.3389/fendo.2012.00001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Accepted: 01/03/2012] [Indexed: 12/22/2022] Open
Abstract
The discovery that a number of metabolites and metabolic intermediates can act through G protein-coupled receptors has attracted great interest in the field and has led to new therapeutic targets for diseases such as hypertension, type 2 diabetes, inflammation, and metabolic syndrome. However, the low apparent affinity of these ligands for their cognate receptors poses a number of challenges for pharmacologists interested in investigating receptor structure, function or physiology. Furthermore, the endogenous ligands matched to their receptors have other, well established metabolic roles and thus selectivity is difficult to achieve. This review discusses some of the issues researchers face when working with these receptors and highlights the ways in which a number of these obstacles have been overcome.
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Affiliation(s)
- Nicola J Smith
- Molecular Cardiology, Victor Chang Cardiac Research Institute Darlinghurst, NSW, Australia.
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41
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Fanelli F, De Benedetti PG. Update 1 of: computational modeling approaches to structure-function analysis of G protein-coupled receptors. Chem Rev 2011; 111:PR438-535. [PMID: 22165845 DOI: 10.1021/cr100437t] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Francesca Fanelli
- Dulbecco Telethon Institute, University of Modena and Reggio Emilia, via Campi 183, 41125 Modena, Italy.
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42
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Bhatt A, Patel PD, Patel MR, Singh S, Lau-Cam CA, Talele TT. CoMSIA Study on Substituted Aryl Alkanoic Acid Analogs as GPR40 Agonists. Chem Biol Drug Des 2011; 77:361-72. [DOI: 10.1111/j.1747-0285.2011.01112.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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43
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Kruska N, Reiser G. Phytanic acid and pristanic acid, branched-chain fatty acids associated with Refsum disease and other inherited peroxisomal disorders, mediate intracellular Ca2+ signaling through activation of free fatty acid receptor GPR40. Neurobiol Dis 2011; 43:465-72. [PMID: 21570468 DOI: 10.1016/j.nbd.2011.04.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 04/18/2011] [Accepted: 04/22/2011] [Indexed: 01/28/2023] Open
Abstract
The accumulation of the two branched-chain fatty acids phytanic acid and pristanic acid is known to play an important role in several diseases with peroxisomal impairment, like Refsum disease, Zellweger syndrome and α-methylacyl-CoA racemase deficiency. Recent studies elucidated that the toxic activity of phytanic acid and pristanic acid is mediated by multiple mitochondrial dysfunctions, generation of reactive oxygen species and Ca2+ deregulation via the InsP3-Ca2+ signaling pathway in glial cells. However, the exact signaling mechanism through which both fatty acids mediate toxicity is still under debate. Here, we studied the ability of phytanic acid and pristanic acid to activate the free fatty acid receptor GPR40, a G-protein-coupled receptor, which was described to be involved in the Ca2+ signaling of fatty acids. We treated HEK 293 cells expressing the GPR40 receptor with phytanic acid or pristanic acid. This resulted in a significant increase in the intracellular Ca2+ level, similar to the effect seen after treatment with the synthetic GPR40 agonist GW9508. Furthermore, we demonstrate that the GPR40 activation might be due to an interaction of the carboxylate moiety of fatty acids with the receptor. Our findings indicate that the phytanic acid- and pristanic acid-mediated Ca2+ deregulation can involve the activation of GPR40. Therefore, we suppose that activation of GPR40 might be part of the signaling cascade of the toxicity of phytanic and pristanic acids.
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Affiliation(s)
- Nicol Kruska
- Institut für Neurobiochemie, Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Leipziger Str. 44, D-39120 Magdeburg, Germany
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44
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Insight into analysis of interactions of GW9508 to wild-type and H86F and H137F GPR40: A combined QM/MM study and pharmacophore modeling. J Mol Graph Model 2011; 29:818-25. [DOI: 10.1016/j.jmgm.2011.01.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 01/13/2011] [Accepted: 01/13/2011] [Indexed: 02/06/2023]
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Vilar S, Karpiak J, Berk B, Costanzi S. In silico analysis of the binding of agonists and blockers to the β2-adrenergic receptor. J Mol Graph Model 2011; 29:809-17. [PMID: 21334234 DOI: 10.1016/j.jmgm.2011.01.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Accepted: 01/12/2011] [Indexed: 10/18/2022]
Abstract
Activation of G protein-coupled receptors (GPCRs) is a complex phenomenon. Here, we applied Induced Fit Docking (IFD) in tandem with linear discriminant analysis (LDA) to generate hypotheses on the conformational changes induced to the β(2)-adrenergic receptor by agonist binding, preliminary to the sequence of events that characterize activation of the receptor. This analysis, corroborated by a follow-up molecular dynamics study, suggested that agonists induce subtle movements to the fifth transmembrane domain (TM5) of the receptor. Furthermore, molecular dynamics also highlighted a correlation between movements of TM5 and the second extracellular loop (EL2), suggesting that freedom of motion of EL2 is required for the agonist-induced TM5 displacement. Importantly, we also showed that the IFD/LDA procedure can be used as a computational means to distinguish agonists from blockers on the basis of the differential conformational changes induced to the receptor. In particular, the two most predictive models obtained are based on the RMSD induced to Ser207 and on the counterclockwise rotation induced to TM5.
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Affiliation(s)
- Santiago Vilar
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, DHHS, Bethesda, MD 20892, USA
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Swaminath G, Jaeckel P, Guo Q, Cardozo M, Weiszmann J, Lindberg R, Wang Y, Schwandner R, Li Y. Mutational analysis of G-protein coupled receptor--FFA2. Biochem Biophys Res Commun 2011; 405:122-7. [PMID: 21216233 DOI: 10.1016/j.bbrc.2010.12.139] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Accepted: 12/31/2010] [Indexed: 12/20/2022]
Abstract
FFA2 (GPR43) is a receptor for short-chain fatty acids (SCFAs), acetate, and propionate. FFA2 is predominantly expressed in islets, a subset of immune cells, adipocytes, and the gastrointestinal tract which suggest a possible role in inflammatory and metabolic conditions. We have previously described the identification and characterization of novel phenylacetamides as allosteric agonists of FFA2. In the current study, we have investigated the molecular determinants contributing to receptor activation with the endogenous and synthetic ligands as well as allosteric interactions between these two sites. The mutational analysis revealed previously unidentified sites that may allosterically regulate orthosteric ligand's function as well as residues potentially important for the interactions between orthosteric and allosteric binding sites.
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Holliday ND, Watson SJ, Brown AJH. Drug discovery opportunities and challenges at g protein coupled receptors for long chain free Fatty acids. Front Endocrinol (Lausanne) 2011; 2:112. [PMID: 22649399 PMCID: PMC3355945 DOI: 10.3389/fendo.2011.00112] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 12/15/2011] [Indexed: 01/13/2023] Open
Abstract
Discovery of G protein coupled receptors for long chain free fatty acids (FFAs), FFA1 (GPR40) and GPR120, has expanded our understanding of these nutrients as signaling molecules. These receptors have emerged as important sensors for FFA levels in the circulation or the gut lumen, based on evidence from in vitro and rodent models, and an increasing number of human studies. Here we consider their promise as therapeutic targets for metabolic disease, including type 2 diabetes and obesity. FFA1 directly mediates acute FFA-induced glucose-stimulated insulin secretion in pancreatic beta-cells, while GPR120 and FFA1 trigger release of incretins from intestinal endocrine cells, and so indirectly enhance insulin secretion and promote satiety. GPR120 signaling in adipocytes and macrophages also results in insulin sensitizing and beneficial anti-inflammatory effects. Drug discovery has focused on agonists to replicate acute benefits of FFA receptor signaling, with promising early results for FFA1 agonists in man. Controversy surrounding chronic effects of FFA1 on beta-cells illustrates that long term benefits of antagonists also need exploring. It has proved challenging to generate highly selective potent ligands for FFA1 or GPR120 subtypes, given that both receptors have hydrophobic orthosteric binding sites, which are not completely defined and have modest ligand affinity. Structure activity relationships are also reliant on functional read outs, in the absence of robust binding assays to provide direct affinity estimates. Nevertheless synthetic ligands have already helped dissect specific contributions of FFA1 and GPR120 signaling from the many possible cellular effects of FFAs. Approaches including use of fluorescent ligand binding assays, and targeting allosteric receptor sites, may improve further pre-clinical ligand development at these receptors, to exploit their unique potential to target multiple facets of diabetes.
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Affiliation(s)
- Nicholas D. Holliday
- Cell Signalling Research Group, School of Biomedical Sciences, The Medical School, Queen’s Medical Centre, University of NottinghamNottingham, UK
- *Correspondence: Nicholas D. Holliday, Cell Signalling Research Group, School of Biomedical Sciences, The Medical School, Queen’s Medical Centre, University of Nottingham, Floor C, Nottingham NG7 2UH, UK. e-mail:
| | - Sarah-Jane Watson
- Cell Signalling Research Group, School of Biomedical Sciences, The Medical School, Queen’s Medical Centre, University of NottinghamNottingham, UK
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Hudson B, Smith NJ, Milligan G. Experimental Challenges to Targeting Poorly Characterized GPCRs: Uncovering the Therapeutic Potential for Free Fatty Acid Receptors. PHARMACOLOGY OF G PROTEIN COUPLED RECEPTORS 2011; 62:175-218. [DOI: 10.1016/b978-0-12-385952-5.00006-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Vilar S, Ferino G, Phatak SS, Berk B, Cavasotto CN, Costanzi S. Docking-based virtual screening for ligands of G protein-coupled receptors: not only crystal structures but also in silico models. J Mol Graph Model 2010; 29:614-23. [PMID: 21146435 DOI: 10.1016/j.jmgm.2010.11.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 10/28/2010] [Accepted: 11/09/2010] [Indexed: 12/21/2022]
Abstract
G protein-coupled receptors (GPCRs) regulate a wide range of physiological functions and hold great pharmaceutical interest. Using the β(2)-adrenergic receptor as a case study, this article explores the applicability of docking-based virtual screening to the discovery of GPCR ligands and defines methods intended to improve the screening performance. Our controlled computational experiments were performed on a compound dataset containing known agonists and blockers of the receptor as well as a large number of decoys. The screening based on the structure of the receptor crystallized in complex with its inverse agonist carazolol yielded excellent results, with a clearly delineated prioritization of ligands over decoys. Blockers generally were preferred over agonists; however, agonists were also well distinguished from decoys. A method was devised to increase the screening yields by generating an ensemble of alternative conformations of the receptor that accounts for its flexibility. Moreover, a method was devised to improve the retrieval of agonists, based on the optimization of the receptor around a known agonist. Finally, the applicability of docking-based virtual screening also to homology models endowed with different levels of accuracy was proved. This last point is of uttermost importance, since crystal structures are available only for a limited number of GPCRs, and extends our conclusions to the entire superfamily. The outcome of this analysis definitely supports the application of computer-aided techniques to the discovery of novel GPCR ligands, especially in light of the fact that, in the near future, experimental structures are expected to be solved and become available for an ever increasing number of GPCRs.
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Affiliation(s)
- Santiago Vilar
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, DHHS, Bethesda, MD 20892, USA
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Swaminath G, Jaeckel P, Guo Q, Cardozo M, Weiszmann J, Lindberg R, Wang Y, Schwandner R, Li Y. Allosteric rescuing of loss-of-function FFAR2 mutations. FEBS Lett 2010; 584:4208-14. [PMID: 20837008 DOI: 10.1016/j.febslet.2010.09.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Revised: 08/08/2010] [Accepted: 09/03/2010] [Indexed: 10/19/2022]
Abstract
FFAR2 (GPR43) is a receptor for short-chain fatty acids (SCFAs), acetate and propionate. In the current study, we investigate the molecular determinants contributing to receptor activation by endogenous ligands. Mutational analysis revealed several important residues located in transmembrane domains (TM) 3, 4, 5, 6, and 7 for acetate binding. Interestingly, mutations that abolished acetate activity, including the mutation in the well-conserved D(E)RY motif, could be rescued by a recently identified synthetic allosteric agonist. These findings provide additional insight into agonist binding and activation which may aid in designing allosteric ligands for targeting receptor function in various diseases.
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