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Fisher CL, Pavan M, Salmaso V, Keyes RF, Wan TC, Pradhan B, Gao ZG, Smith BC, Jacobson KA, Auchampach JA. Extrahelical Binding Site for a 1 H-Imidazo[4,5-c]quinolin-4-amine A 3 Adenosine Receptor Positive Allosteric Modulator on Helix 8 and Distal Portions of Transmembrane Domains 1 and 7. Mol Pharmacol 2024; 105:213-223. [PMID: 38182432 PMCID: PMC10877738 DOI: 10.1124/molpharm.123.000784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 11/27/2023] [Accepted: 12/12/2023] [Indexed: 01/07/2024] Open
Abstract
This study describes the localization and computational prediction of a binding site for the A3 adenosine receptor (A3AR) positive allosteric modulator 2-cyclohexyl-1H-imidazo[4,5-c]quinolin-4-(3,4-dichlorophenyl)amine (LUF6000). The work reveals an extrahelical lipid-facing binding pocket disparate from the orthosteric binding site that encompasses transmembrane domain (TMD) 1, TMD7, and Helix (H) 8, which was predicted by molecular modeling and validated by mutagenesis. According to the model, the nearly planar 1H-imidazo[4,5-c]quinolinamine ring system lies parallel to the transmembrane segments, inserted into an aromatic cage formed by π-π stacking interactions with the side chains of Y2847.55 in TMD7 and Y2938.54 in H8 and by π-NH bonding between Y2847.55 and the exocyclic amine. The 2-cyclohexyl group is positioned "upward" within a small hydrophobic subpocket created by residues in TMDs 1 and 7, while the 3,4-dichlorophenyl group extends toward the lipid interface. An H-bond between the N-1 amine of the heterocycle and the carbonyl of G291.49 further stabilizes the interaction. Molecular dynamics simulations predicted two metastable intermediates, one resembling a pose determined by molecular docking and a second involving transient interactions with Y2938.54; in simulations, each of these intermediates converges into the final bound state. Structure-activity-relationships for replacement of either of the identified exocyclic or endocyclic amines with heteroatoms lacking H-bond donating ability were consistent with the hypothetical pose. Thus, we characterized an allosteric pocket for 1H-imidazo[4,5-c]quinolin-4-amines that is consistent with data generated by orthogonal methods, which will aid in the rational design of improved A3AR positive allosteric modulators. SIGNIFICANCE STATEMENT: Orthosteric A3AR agonists have advanced in clinical trials for inflammatory conditions, liver diseases, and cancer. Thus, the clinical appeal of selective receptor activation could extend to allosteric enhancers, which would induce site- and time-specific activation in the affected tissue. By identifying the allosteric site for known positive allosteric modulators, structure-based drug discovery modalities can be enabled to enhance the pharmacological properties of the 1H-imidazo[4,5-c]quinolin-4-amine class of A3AR positive allosteric modulators.
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Affiliation(s)
- Courtney L Fisher
- Departments of Pharmacology & Toxicology and the Cardiovascular Center (C.L.F., T.C.W., J.A.A.) and Biochemistry and the Program in Chemical Biology (R.F.K., B.C.S.), Medical College of Wisconsin, Milwaukee, Wisconsin; Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (M.P., V.S., B.P., Z.-G.G., K.A.J.); and Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Padua, Italy (V.S.)
| | - Matteo Pavan
- Departments of Pharmacology & Toxicology and the Cardiovascular Center (C.L.F., T.C.W., J.A.A.) and Biochemistry and the Program in Chemical Biology (R.F.K., B.C.S.), Medical College of Wisconsin, Milwaukee, Wisconsin; Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (M.P., V.S., B.P., Z.-G.G., K.A.J.); and Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Padua, Italy (V.S.)
| | - Veronica Salmaso
- Departments of Pharmacology & Toxicology and the Cardiovascular Center (C.L.F., T.C.W., J.A.A.) and Biochemistry and the Program in Chemical Biology (R.F.K., B.C.S.), Medical College of Wisconsin, Milwaukee, Wisconsin; Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (M.P., V.S., B.P., Z.-G.G., K.A.J.); and Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Padua, Italy (V.S.)
| | - Robert F Keyes
- Departments of Pharmacology & Toxicology and the Cardiovascular Center (C.L.F., T.C.W., J.A.A.) and Biochemistry and the Program in Chemical Biology (R.F.K., B.C.S.), Medical College of Wisconsin, Milwaukee, Wisconsin; Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (M.P., V.S., B.P., Z.-G.G., K.A.J.); and Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Padua, Italy (V.S.)
| | - Tina C Wan
- Departments of Pharmacology & Toxicology and the Cardiovascular Center (C.L.F., T.C.W., J.A.A.) and Biochemistry and the Program in Chemical Biology (R.F.K., B.C.S.), Medical College of Wisconsin, Milwaukee, Wisconsin; Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (M.P., V.S., B.P., Z.-G.G., K.A.J.); and Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Padua, Italy (V.S.)
| | - Balaram Pradhan
- Departments of Pharmacology & Toxicology and the Cardiovascular Center (C.L.F., T.C.W., J.A.A.) and Biochemistry and the Program in Chemical Biology (R.F.K., B.C.S.), Medical College of Wisconsin, Milwaukee, Wisconsin; Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (M.P., V.S., B.P., Z.-G.G., K.A.J.); and Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Padua, Italy (V.S.)
| | - Zhan-Guo Gao
- Departments of Pharmacology & Toxicology and the Cardiovascular Center (C.L.F., T.C.W., J.A.A.) and Biochemistry and the Program in Chemical Biology (R.F.K., B.C.S.), Medical College of Wisconsin, Milwaukee, Wisconsin; Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (M.P., V.S., B.P., Z.-G.G., K.A.J.); and Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Padua, Italy (V.S.)
| | - Brian C Smith
- Departments of Pharmacology & Toxicology and the Cardiovascular Center (C.L.F., T.C.W., J.A.A.) and Biochemistry and the Program in Chemical Biology (R.F.K., B.C.S.), Medical College of Wisconsin, Milwaukee, Wisconsin; Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (M.P., V.S., B.P., Z.-G.G., K.A.J.); and Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Padua, Italy (V.S.)
| | - Kenneth A Jacobson
- Departments of Pharmacology & Toxicology and the Cardiovascular Center (C.L.F., T.C.W., J.A.A.) and Biochemistry and the Program in Chemical Biology (R.F.K., B.C.S.), Medical College of Wisconsin, Milwaukee, Wisconsin; Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (M.P., V.S., B.P., Z.-G.G., K.A.J.); and Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Padua, Italy (V.S.)
| | - John A Auchampach
- Departments of Pharmacology & Toxicology and the Cardiovascular Center (C.L.F., T.C.W., J.A.A.) and Biochemistry and the Program in Chemical Biology (R.F.K., B.C.S.), Medical College of Wisconsin, Milwaukee, Wisconsin; Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (M.P., V.S., B.P., Z.-G.G., K.A.J.); and Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Padua, Italy (V.S.)
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Ahn S, Maarsingh H, Walker JK, Liu S, Hegde A, Sumajit HC, Kahsai AW, Lefkowitz RJ. Allosteric modulator potentiates β2AR agonist-promoted bronchoprotection in asthma models. J Clin Invest 2023; 133:e167337. [PMID: 37432742 PMCID: PMC10503797 DOI: 10.1172/jci167337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 07/06/2023] [Indexed: 07/12/2023] Open
Abstract
Asthma is a chronic inflammatory disease associated with episodic airway narrowing. Inhaled β2-adrenergic receptor (β2AR) agonists (β2-agonists) promote - with limited efficacy - bronchodilation in asthma. All β2-agonists are canonical orthosteric ligands that bind the same site as endogenous epinephrine. We recently isolated a β2AR-selective positive allosteric modulator (PAM), compound-6 (Cmpd-6), which binds outside of the orthosteric site and modulates orthosteric ligand functions. With the emerging therapeutic potential of G-protein coupled receptor allosteric ligands, we investigated the impact of Cmpd-6 on β2AR-mediated bronchoprotection. Consistent with our findings using human β2ARs, Cmpd-6 allosterically potentiated β2-agonist binding to guinea pig β2ARs and downstream signaling of β2ARs. In contrast, Cmpd-6 had no such effect on murine β2ARs, which lack a crucial amino acid in the Cmpd-6 allosteric binding site. Importantly, Cmpd-6 enhanced β2 agonist-mediated bronchoprotection against methacholine-induced bronchoconstriction in guinea pig lung slices, but - in line with the binding studies - not in mice. Moreover, Cmpd-6 robustly potentiated β2 agonist-mediated bronchoprotection against allergen-induced airway constriction in lung slices obtained from a guinea pig model of allergic asthma. Cmpd-6 similarly enhanced β2 agonist-mediated bronchoprotection against methacholine-induced bronchoconstriction in human lung slices. Our results highlight the potential of β2AR-selective PAMs in the treatment of airway narrowing in asthma and other obstructive respiratory diseases.
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Affiliation(s)
- Seungkirl Ahn
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Harm Maarsingh
- Department of Pharmaceutical Sciences, Lloyd L. Gregory School of Pharmacy, Palm Beach Atlantic University, West Palm Beach, Florida, USA
| | - Julia K.L. Walker
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
- School of Nursing, Duke University, Durham, North Carolina, USA
| | - Samuel Liu
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Akhil Hegde
- School of Nursing, Duke University, Durham, North Carolina, USA
| | - Hyeje C. Sumajit
- Department of Pharmaceutical Sciences, Lloyd L. Gregory School of Pharmacy, Palm Beach Atlantic University, West Palm Beach, Florida, USA
| | - Alem W. Kahsai
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Robert J. Lefkowitz
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Biochemistry and
- Howard Hughes Medical Institute, Duke University School of Medicine, Durham, North Carolina, USA
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Gao ZG, Auchampach JA, Jacobson KA. Species dependence of A 3 adenosine receptor pharmacology and function. Purinergic Signal 2023; 19:523-550. [PMID: 36538251 PMCID: PMC9763816 DOI: 10.1007/s11302-022-09910-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 11/26/2022] [Indexed: 12/24/2022] Open
Abstract
Efforts to fully understand pharmacological differences between G protein-coupled receptor (GPCR) species homologues are generally not pursued in detail during the drug development process. To date, many GPCRs that have been successfully targeted are relatively well-conserved across species in amino acid sequence and display minimal variability of biological effects. However, the A3 adenosine receptor (AR), an exciting drug target for a multitude of diseases associated with tissue injury, ischemia, and inflammation, displays as little as 70% sequence identity among mammalian species (e.g., rodent vs. primate) commonly used in drug development. Consequently, the pharmacological properties of synthetic A3AR ligands vary widely, not only in binding affinity, selectivity, and signaling efficacy, but to the extent that some function as agonists in some species and antagonists in others. Numerous heterocyclic antagonists that have nM affinity at the human A3AR are inactive or weakly active at the rat and mouse A3ARs. Positive allosteric modulators, including the imidazo [4,5-c]quinolin-4-amine derivative LUF6000, are only active at human and some larger animal species that have been evaluated (rabbit and dog), but not rodents. A3AR agonists evoke systemic degranulation of rodent, but not human mast cells. The rat A3AR undergoes desensitization faster than the human A3AR, but the human homologue can be completely re-sensitized and recycled back to the cell surface. Thus, comprehensive pharmacological evaluation and awareness of potential A3AR species differences are critical in studies to further understand the basic biological functions of this unique AR subtype. Recombinant A3ARs from eight different species have been pharmacologically characterized thus far. In this review, we describe in detail current knowledge of species differences in genetic identity, G protein-coupling, receptor regulation, and both orthosteric and allosteric A3AR pharmacology.
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Affiliation(s)
- Zhan-Guo Gao
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892-0810, USA.
| | - John A Auchampach
- Department of Pharmacology and Toxicology, and the Cardiovascular Center, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA
| | - Kenneth A Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892-0810, USA.
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Saito A, Alvi S, Valant C, Christopoulos A, Carbone SE, Poole DP. Therapeutic potential of allosteric modulators for the treatment of gastrointestinal motility disorders. Br J Pharmacol 2022. [PMID: 36565295 DOI: 10.1111/bph.16023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/24/2022] [Accepted: 12/09/2022] [Indexed: 12/25/2022] Open
Abstract
Gastrointestinal motility is tightly regulated by the enteric nervous system (ENS). Disruption of coordinated enteric nervous system activity can result in dysmotility. Pharmacological treatment options for dysmotility include targeting of G protein-coupled receptors (GPCRs) expressed by neurons of the enteric nervous system. Current GPCR-targeting drugs for motility disorders bind to the highly conserved endogenous ligand-binding site and promote indiscriminate activation or inhibition of the target receptor throughout the body. This can be associated with significant side-effect liability and a loss of physiological tone. Allosteric modulators of GPCRs bind to a distinct site from the endogenous ligand, which is typically less conserved across multiple receptor subtypes and can modulate endogenous ligand signalling. Allosteric modulation of GPCRs that are important for enteric nervous system function may provide effective relief from motility disorders while limiting side-effects. This review will focus on how allosteric modulators of GPCRs may influence gastrointestinal motility, using 5-hydroxytryptamine (5-HT), acetylcholine (ACh) and opioid receptors as examples.
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Affiliation(s)
- Ayame Saito
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia
| | - Sadia Alvi
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia
| | - Celine Valant
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia
| | - Arthur Christopoulos
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia
| | - Simona E Carbone
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia
| | - Daniel P Poole
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia
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5
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Fallot LB, Suresh RR, Fisher CL, Salmaso V, O'Connor RD, Kaufman N, Gao ZG, Auchampach JA, Jacobson KA. Structure-Activity Studies of 1 H-Imidazo[4,5- c]quinolin-4-amine Derivatives as A 3 Adenosine Receptor Positive Allosteric Modulators. J Med Chem 2022; 65:15238-15262. [PMID: 36367749 PMCID: PMC10354740 DOI: 10.1021/acs.jmedchem.2c01170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We previously reported 1H-imidazo[4,5-c]quinolin-4-amines as A3 adenosine receptor (A3AR) positive allosteric modulators (PAMs). A3AR agonists, but not PAMs, are in clinical trials for inflammatory diseases and liver conditions. We synthesized new analogues to distinguish 2-cyclopropyl antagonist 17 (orthosteric interaction demonstrated by binding and predicted computationally) from PAMs (derivatives with large 2-alkyl/cycloalkyl/bicycloalkyl groups). We predicted PAM binding at a hydrophobic site on the A3AR cytosolic interface. Although having low Caco-2 permeability and high plasma protein binding, hydrophobic 2-cyclohept-4-enyl-N-3,4-dichlorophenyl, MRS7788 18, and 2-heptan-4-yl-N-4-iodophenyl, MRS8054 39, derivatives were orally bioavailable in rat. 2-Heptan-4-yl-N-3,4-dichlorophenyl 14 and 2-cyclononyl-N-3,4-dichlorophenyl 20 derivatives and 39 greatly enhanced Cl-IB-MECA-stimulated [35S]GTPγS binding Emax, with only 12b trending toward decreasing the agonist EC50. A feasible route for radio-iodination at the p-position of a 4-phenylamino substituent suggests a potential radioligand for allosteric site binding. Herein, we advanced an allosteric approach to developing A3AR-activating drugs that are potentially event- and site-specific in action.
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Affiliation(s)
- Lucas B Fallot
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, Maryland 20814, United States
- Department of Chemistry and Life Science, United States Military Academy, 646 Swift Road, West Point, New York 10996, United States
| | - R Rama Suresh
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | | | - Veronica Salmaso
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - Robert D O'Connor
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - Noy Kaufman
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - Zhan-Guo Gao
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | | | - Kenneth A Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
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Fisher CL, Fallot LB, Wan TC, Keyes RF, Suresh RR, Rothwell AC, Gao ZG, McCorvy JD, Smith BC, Jacobson KA, Auchampach JA. Characterization of Dual-Acting A 3 Adenosine Receptor Positive Allosteric Modulators That Preferentially Enhance Adenosine-Induced Gα i3 and Gα oA Isoprotein Activation. ACS Pharmacol Transl Sci 2022; 5:625-641. [PMID: 35983277 PMCID: PMC9380209 DOI: 10.1021/acsptsci.2c00076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Indexed: 12/19/2022]
Abstract
The A3 adenosine receptor (A3AR) is a promising therapeutic target for inflammatory diseases, cancer, and chronic neuropathic pain, with agonists already in advanced clinical trials. Here we report an in-depth comparison of the pharmacological properties and structure-activity relationships of existing and expanded compound libraries of 2-substituted 1H-imidazo[4,5-c]quinolin-4-amine and 4-amino-substituted quinoline derivatives that function as A3AR positive allosteric modulators (PAMs). We also show that our lead compound from each series enhances adenosine-induced A3AR signaling preferentially toward activation of Gαi3 and GαoA isoproteins, which are coexpressed with the A3AR in immune cells and spinal cord neurons. Finally, utilizing an extracellular/intracellular chimeric A3AR approach composed of sequences from a responding (human) and a nonresponding (mouse) species, we provide evidence in support of the idea that the imidazoquinolin-4-amine class of PAMs variably interacts dually with the orthosteric ligand binding site as well as with a separate allosteric site located within the inner/intracellular regions of the receptor. This study has advanced both structural and pharmacological understanding of these two classes of A3AR PAMs, which includes leads for future pharmaceutical development.
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Affiliation(s)
- Courtney L. Fisher
- Department of Pharmacology & Toxicology and the Cardiovascular Center, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, Wisconsin 53226, United States
| | - Lucas B. Fallot
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
- Department of Biochemistry & Molecular Biology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, Maryland 20814, United States
- Department of Chemistry & Life Science, United States Military Academy, 646 Swift Road, West Point, New York 10996, United States
| | - Tina C. Wan
- Department of Pharmacology & Toxicology and the Cardiovascular Center, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, Wisconsin 53226, United States
| | - Robert F. Keyes
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, Wisconsin 53226, United States
| | - R. Rama Suresh
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - Amy C. Rothwell
- Department of Pharmacology & Toxicology and the Cardiovascular Center, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, Wisconsin 53226, United States
| | - Zhan-Guo Gao
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - John D. McCorvy
- Department of Cell Biology, Neurobiology, & Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, Wisconsin 53226, United States
| | - Brian C. Smith
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, Wisconsin 53226, United States
| | - Kenneth A. Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - John A. Auchampach
- Department of Pharmacology & Toxicology and the Cardiovascular Center, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, Wisconsin 53226, United States
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7
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IJzerman AP, Jacobson KA, Müller CE, Cronstein BN, Cunha RA. International Union of Basic and Clinical Pharmacology. CXII: Adenosine Receptors: A Further Update. Pharmacol Rev 2022; 74:340-372. [PMID: 35302044 PMCID: PMC8973513 DOI: 10.1124/pharmrev.121.000445] [Citation(s) in RCA: 56] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Our previous International Union of Basic and Clinical Pharmacology report on the nomenclature and classification of adenosine receptors (2011) contained a number of emerging developments with respect to this G protein-coupled receptor subfamily, including protein structure, protein oligomerization, protein diversity, and allosteric modulation by small molecules. Since then, a wealth of new data and results has been added, allowing us to explore novel concepts such as target binding kinetics and biased signaling of adenosine receptors, to examine a multitude of receptor structures and novel ligands, to gauge new pharmacology, and to evaluate clinical trials with adenosine receptor ligands. This review should therefore be considered a further update of our previous reports from 2001 and 2011. SIGNIFICANCE STATEMENT: Adenosine receptors (ARs) are of continuing interest for future treatment of chronic and acute disease conditions, including inflammatory diseases, neurodegenerative afflictions, and cancer. The design of AR agonists ("biased" or not) and antagonists is largely structure based now, thanks to the tremendous progress in AR structural biology. The A2A- and A2BAR appear to modulate the immune response in tumor biology. Many clinical trials for this indication are ongoing, whereas an A2AAR antagonist (istradefylline) has been approved as an anti-Parkinson agent.
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Affiliation(s)
- Adriaan P IJzerman
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands (A.P.IJ.); National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Molecular Recognition Section, Bethesda, Maryland (K.A.J.); Universität Bonn, Bonn, Germany (C.E.M.); New York University School of Medicine, New York, New York (B.N.C.); and Center for Neurosciences and Cell Biology and Faculty of Medicine, University of Coimbra, Coimbra, Portugal (R.A.C.)
| | - Kenneth A Jacobson
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands (A.P.IJ.); National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Molecular Recognition Section, Bethesda, Maryland (K.A.J.); Universität Bonn, Bonn, Germany (C.E.M.); New York University School of Medicine, New York, New York (B.N.C.); and Center for Neurosciences and Cell Biology and Faculty of Medicine, University of Coimbra, Coimbra, Portugal (R.A.C.)
| | - Christa E Müller
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands (A.P.IJ.); National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Molecular Recognition Section, Bethesda, Maryland (K.A.J.); Universität Bonn, Bonn, Germany (C.E.M.); New York University School of Medicine, New York, New York (B.N.C.); and Center for Neurosciences and Cell Biology and Faculty of Medicine, University of Coimbra, Coimbra, Portugal (R.A.C.)
| | - Bruce N Cronstein
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands (A.P.IJ.); National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Molecular Recognition Section, Bethesda, Maryland (K.A.J.); Universität Bonn, Bonn, Germany (C.E.M.); New York University School of Medicine, New York, New York (B.N.C.); and Center for Neurosciences and Cell Biology and Faculty of Medicine, University of Coimbra, Coimbra, Portugal (R.A.C.)
| | - Rodrigo A Cunha
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands (A.P.IJ.); National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Molecular Recognition Section, Bethesda, Maryland (K.A.J.); Universität Bonn, Bonn, Germany (C.E.M.); New York University School of Medicine, New York, New York (B.N.C.); and Center for Neurosciences and Cell Biology and Faculty of Medicine, University of Coimbra, Coimbra, Portugal (R.A.C.)
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Salmaso V, Jacobson KA. Purinergic Signaling: Impact of GPCR Structures on Rational Drug Design. ChemMedChem 2020; 15:1958-1973. [PMID: 32803849 PMCID: PMC8276773 DOI: 10.1002/cmdc.202000465] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Indexed: 12/16/2022]
Abstract
The purinergic signaling system includes membrane-bound receptors for extracellular purines and pyrimidines, and enzymes/transporters that regulate receptor activation by endogenous agonists. Receptors include: adenosine (A1 , A2A , A2B, and A3 ) and P2Y (P2Y1 , P2Y2 , P2Y4 , P2Y6 , P2Y11 , P2Y12 , P2Y13 , and P2Y14 ) receptors (all GPCRs), as well as P2X receptors (ion channels). Receptor activation, especially accompanying physiological stress or damage, creates a temporal sequence of signaling to counteract this stress and either mobilize (P2Rs) or suppress (ARs) immune responses. Thus, modulation of this large signaling family has broad potential for treating chronic diseases. Experimentally determined structures represent each of the three receptor families. We focus on selective purinergic agonists (A1 , A3 ), antagonists (A3 , P2Y14 ), and allosteric modulators (P2Y1 , A3 ). Examples of applying structure-based design, including the rational modification of known ligands, are presented for antithrombotic P2Y1 R antagonists and anti-inflammatory P2Y14 R antagonists and A3 AR agonists. A3 AR agonists are a potential, nonaddictive treatment for chronic neuropathic pain.
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Affiliation(s)
- Veronica Salmaso
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes & Digestive & Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kenneth A Jacobson
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes & Digestive & Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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Tosh DK, Salmaso V, Rao H, Campbell R, Bitant A, Gao ZG, Auchampach JA, Jacobson KA. Direct Comparison of (N)-Methanocarba and Ribose-Containing 2-Arylalkynyladenosine Derivatives as A 3 Receptor Agonists. ACS Med Chem Lett 2020; 11:1935-1941. [PMID: 33062176 DOI: 10.1021/acsmedchemlett.9b00637] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 02/07/2020] [Indexed: 12/12/2022] Open
Abstract
A side-by-side pharmacological comparison of ribose and (N)-methanocarba (bicyclo[3.1.0]hexane) nucleosides as A3AR agonists indicated that the bicyclic pseudoribose ring constraint provided higher affinity/selectivity at human and mouse A3AR. The mean affinity enhancement for 5 pairs of 5'-methylamides was 11-fold at hA3AR and 42-fold at mA3AR. Novel C2-(5-fluorothien-2-ylethynyl) substitution enhanced affinity in the methanocarba but not ribose series, with highly hA3AR-selective 16 (MRS7334) displaying Ki 280 pM and favorable pharmacokinetics and off-target activity profile. Molecular dynamics comparison of 16 and its corresponding riboside 8 suggested a qualitative entropic advantage of 16 in hA3AR binding. The 5-F substitution tended to increase hA3AR affinity (cf. 5-Cl) for methanocarba but not ribose derivatives. A representative methanocarba agonist 4 was shown to interact potently exclusively with A3AR, among 240 GPCRs and 466 kinases. Thus, despite added synthetic difficulty, the (N)-methanocarba modification has distinct advantages for A3AR agonists, which have translational potential for chronic disease treatment.
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Affiliation(s)
- Dilip K. Tosh
- Laboratory of Bioorganic Chemistry, Mouse Metabolism Core, and Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - Veronica Salmaso
- Laboratory of Bioorganic Chemistry, Mouse Metabolism Core, and Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - Harsha Rao
- Laboratory of Bioorganic Chemistry, Mouse Metabolism Core, and Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - Ryan Campbell
- Laboratory of Bioorganic Chemistry, Mouse Metabolism Core, and Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - Amelia Bitant
- Department of Pharmacology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, Wisconsin 53226, United States
| | - Zhan-Guo Gao
- Laboratory of Bioorganic Chemistry, Mouse Metabolism Core, and Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - John A. Auchampach
- Department of Pharmacology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, Wisconsin 53226, United States
| | - Kenneth A. Jacobson
- Laboratory of Bioorganic Chemistry, Mouse Metabolism Core, and Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
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10
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Tosh DK, Salmaso V, Rao H, Bitant A, Fisher CL, Lieberman DI, Vorbrüggen H, Reitman ML, Gavrilova O, Gao ZG, Auchampach JA, Jacobson KA. Truncated (N)-Methanocarba Nucleosides as Partial Agonists at Mouse and Human A 3 Adenosine Receptors: Affinity Enhancement by N6-(2-Phenylethyl) Substitution. J Med Chem 2020; 63:4334-4348. [PMID: 32271569 PMCID: PMC7443318 DOI: 10.1021/acs.jmedchem.0c00235] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Dopamine-derived N6-substituents, compared to N6-(2-phenylethyl), in truncated (N)-methanocarba (bicyclo[3.1.0]hexyl) adenosines favored high A3 adenosine receptor (AR) affinity/selectivity, e.g., C2-phenylethynyl analogue 15 (MRS7591, Ki = 10.9/17.8 nM, at human/mouse A3AR). 15 was a partial agonist in vitro (hA3AR, cAMP inhibition, 31% Emax; mA3AR, [35S]GTP-γ-S binding, 16% Emax) and in vivo and also antagonized hA3AR in vitro. Distal H-bonding substitutions of the N6-(2-phenylethyl) moiety particularly enhanced mA3AR affinity by polar interactions with the extracellular loops, predicted using docking and molecular dynamics simulation with newly constructed mA3AR and hA3AR homology models. These hybrid models were based on an inactive antagonist-bound hA1AR structure for the upper part of TM2 and an agonist-bound hA2AAR structure for the remaining TM portions. These species-independent A3AR-selective nucleosides are low efficacy partial agonists and novel, nuanced modulators of the A3AR, a drug target of growing interest.
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Affiliation(s)
| | | | | | - Amelia Bitant
- Department of Pharmacology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, USA 53226
| | - Courtney L. Fisher
- Department of Pharmacology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, USA 53226
| | | | - Helmut Vorbrüggen
- Institut für Chemie und Biochemie, Freie Universität, Takustr. 3, D-14195 Berlin, Germany
| | | | - Oksana Gavrilova
- Mouse Metabolism Core, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, MA, USA 20892
| | | | - John A. Auchampach
- Department of Pharmacology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, USA 53226
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Jacobson KA, Tosh DK, Jain S, Gao ZG. Historical and Current Adenosine Receptor Agonists in Preclinical and Clinical Development. Front Cell Neurosci 2019; 13:124. [PMID: 30983976 PMCID: PMC6447611 DOI: 10.3389/fncel.2019.00124] [Citation(s) in RCA: 128] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 03/13/2019] [Indexed: 12/22/2022] Open
Abstract
Adenosine receptors (ARs) function in the body’s response to conditions of pathology and stress associated with a functional imbalance, such as in the supply and demand of energy/oxygen/nutrients. Extracellular adenosine concentrations vary widely to raise or lower the basal activation of four subtypes of ARs. Endogenous adenosine can correct an energy imbalance during hypoxia and other stress, for example, by slowing the heart rate by A1AR activation or increasing the blood supply to heart muscle by the A2AAR. Moreover, exogenous AR agonists, antagonists, or allosteric modulators can be applied for therapeutic benefit, and medicinal chemists working toward that goal have reported thousands of such agents. Thus, numerous clinical trials have ensued, using promising agents to modulate adenosinergic signaling, most of which have not succeeded. Currently, short-acting, parenteral agonists, adenosine and Regadenoson, are the only AR agonists approved for human use. However, new concepts and compounds are currently being developed and applied toward preclinical and clinical evaluation, and initial results are encouraging. This review focuses on key compounds as AR agonists and positive allosteric modulators (PAMs) for disease treatment or diagnosis. AR agonists for treating inflammation, pain, cancer, non-alcoholic steatohepatitis, angina, sickle cell disease, ischemic conditions and diabetes have been under development. Multiple clinical trials with two A3AR agonists are ongoing.
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Affiliation(s)
- Kenneth A Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Dilip K Tosh
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Shanu Jain
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Zhan-Guo Gao
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
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12
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Tosh DK, Rao H, Bitant A, Salmaso V, Mannes P, Lieberman DI, Vaughan KL, Mattison JA, Rothwell AC, Auchampach JA, Ciancetta A, Liu N, Cui Z, Gao ZG, Reitman ML, Gavrilova O, Jacobson KA. Design and in Vivo Characterization of A 1 Adenosine Receptor Agonists in the Native Ribose and Conformationally Constrained (N)-Methanocarba Series. J Med Chem 2019; 62:1502-1522. [PMID: 30605331 DOI: 10.1021/acs.jmedchem.8b01662] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
(N)-Methanocarba ([3.1.0]bicyclohexyl) adenosines and corresponding ribosides were synthesized to identify novel A1 adenosine receptor (A1AR) agonists for CNS or peripheral applications. Human and mouse AR binding was determined to assess the constrained ring system's A1AR compatibility. N6-Dicyclobutylmethyl ribose agonist (9, MRS7469, >2000-fold selective for A1AR) and known truncated N6-dicyclopropylmethyl methanocarba 7 (MRS5474) were drug-like. The pure diastereoisomer of known riboside 4 displayed high hA1AR selectivity. Methanocarba modification reduced A1AR selectivity of N6-dicyclopropylmethyl and endo-norbornyladenosines but increased ribavirin selectivity. Most analogues tested (ip) were inactive or weak in inducing mouse hypothermia, despite mA1AR full agonism and variable mA3AR efficacy, but strong hypothermia by 9 depended on A1AR, which reflects CNS activity (determined using A1AR or A3AR null mice). Conserved hA1AR interactions were preserved in modeling of 9 and methanocarba equivalent 24 (∼400-fold A1AR-selective). Thus, we identified, and characterized in vivo, ribose and methanocarba nucleosides, including with A1AR-enhancing N6-dicyclobutylmethyl-adenine and 1,2,4-triazole-3-carboxamide (40, MRS7451) nucleobases.
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Affiliation(s)
| | | | - Amelia Bitant
- Department of Pharmacology , Medical College of Wisconsin , 8701 Watertown Plank Road , Milwaukee , Wisconsin 53226 , United States
| | | | | | | | - Kelli L Vaughan
- SoBran BioSciences , SoBran, Inc. , 4000 Blackburn Lane , Burtonsville , Maryland 20866 , United States.,Translational Gerontology Branch , National Institute on Aging Intramural Research Program , 16701 Elmer School Road, Building 103 , Dickerson , Maryland 20842 , United States
| | - Julie A Mattison
- Translational Gerontology Branch , National Institute on Aging Intramural Research Program , 16701 Elmer School Road, Building 103 , Dickerson , Maryland 20842 , United States
| | - Amy C Rothwell
- Department of Pharmacology , Medical College of Wisconsin , 8701 Watertown Plank Road , Milwaukee , Wisconsin 53226 , United States
| | - John A Auchampach
- Department of Pharmacology , Medical College of Wisconsin , 8701 Watertown Plank Road , Milwaukee , Wisconsin 53226 , United States
| | - Antonella Ciancetta
- School of Pharmacy , Queen's University Belfast , 96 Lisburn Road , Belfast BT9 7BL , U.K
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Jacobson KA, Tosh DK, Jain S, Gao ZG. Historical and Current Adenosine Receptor Agonists in Preclinical and Clinical Development. Front Cell Neurosci 2019. [PMID: 30983976 DOI: 10.3389/fncel.2019.00124/bibtex] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Adenosine receptors (ARs) function in the body's response to conditions of pathology and stress associated with a functional imbalance, such as in the supply and demand of energy/oxygen/nutrients. Extracellular adenosine concentrations vary widely to raise or lower the basal activation of four subtypes of ARs. Endogenous adenosine can correct an energy imbalance during hypoxia and other stress, for example, by slowing the heart rate by A1AR activation or increasing the blood supply to heart muscle by the A2AAR. Moreover, exogenous AR agonists, antagonists, or allosteric modulators can be applied for therapeutic benefit, and medicinal chemists working toward that goal have reported thousands of such agents. Thus, numerous clinical trials have ensued, using promising agents to modulate adenosinergic signaling, most of which have not succeeded. Currently, short-acting, parenteral agonists, adenosine and Regadenoson, are the only AR agonists approved for human use. However, new concepts and compounds are currently being developed and applied toward preclinical and clinical evaluation, and initial results are encouraging. This review focuses on key compounds as AR agonists and positive allosteric modulators (PAMs) for disease treatment or diagnosis. AR agonists for treating inflammation, pain, cancer, non-alcoholic steatohepatitis, angina, sickle cell disease, ischemic conditions and diabetes have been under development. Multiple clinical trials with two A3AR agonists are ongoing.
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Affiliation(s)
- Kenneth A Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Dilip K Tosh
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Shanu Jain
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Zhan-Guo Gao
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
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