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Keen R, Hardy D, Jose B, Erturk HN. Effects of caffeine on temporal perception in Rattus norvegicus. PLoS One 2024; 19:e0304608. [PMID: 38820365 PMCID: PMC11142558 DOI: 10.1371/journal.pone.0304608] [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: 07/05/2023] [Accepted: 05/14/2024] [Indexed: 06/02/2024] Open
Abstract
We report two studies that tested the effects of caffeine, the world's most widely used psychoactive drug, on temporal perception. We trained Wistar rats using the Bisection Procedure (Experiment 1) or the Stubbs' Procedure (Experiment 2) to discriminate between short and long light stimuli. Once training finished, we administered caffeine orally (0, 9.6, and 96.0 mg/kg for Experiment 1 and 0, 9.6, 19.2, and 38.4 mg/kg for Experiment 2) 15 minutes prior to testing. Relative to the control condition, the 9.6 mg/kg condition (Experiments 1 and 2) and the 19.2 mg/kg condition (Experiment 2) resulted in an increase in proportion of choosing the long response. Meanwhile, overall accuracy was not affected by any condition in both experiments. Taken together, these results are consistent with the notion that caffeine, at some doses, speeds up temporal perception. However, it is not clear why the effect disappears at higher doses.
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Affiliation(s)
- Richard Keen
- Department of Psychology, Converse University, Spartanburg, South Carolina, United States of America
| | - Dalene Hardy
- Department of Psychology, Converse University, Spartanburg, South Carolina, United States of America
- Department of Biology, Chemistry, and Physics, Converse University, Spartanburg, South Carolina, United States of America
| | - Belda Jose
- Department of Psychology, Converse University, Spartanburg, South Carolina, United States of America
- Department of Biology, Chemistry, and Physics, Converse University, Spartanburg, South Carolina, United States of America
| | - H. Neval Erturk
- Department of Biology, Chemistry, and Physics, Converse University, Spartanburg, South Carolina, United States of America
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2
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Fonseca-Barriendos D, Frías-Soria CL, Pérez-Pérez D, Gómez-López R, Borroto Escuela DO, Rocha L. Drug-resistant epilepsy: Drug target hypothesis and beyond the receptors. Epilepsia Open 2021; 7 Suppl 1:S23-S33. [PMID: 34542940 PMCID: PMC9340308 DOI: 10.1002/epi4.12539] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 08/21/2021] [Accepted: 08/27/2021] [Indexed: 12/28/2022] Open
Abstract
Epilepsy is a chronic neurological disorder that affects more than 50 million people worldwide. Despite a recent introduction of antiseizure drugs for the treatment of epileptic seizures, one-third of these patients suffer from drug-resistant epilepsy (DRE). The therapeutic target hypothesis is a cited theory to explain DRE. According to the target hypothesis, the failure to achieve seizure freedom leads to alteration of the structure and/or function of the antiseizure medication (ASM) target. However, this hypothesis fails to explain why patients with DRE do not respond to antiseizure medications of different targets. This review presents different conditions, such as epigenetic mechanisms and protein-protein interactions that may result in alterations of diverse drug targets using different mechanisms. These novel conditions represent new targets to control DRE.
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Affiliation(s)
| | | | - Daniel Pérez-Pérez
- Plan of Combined Studies in Medicine (PECEM), Faculty of Medicine, UNAM, México City, Mexico
| | - Rosenda Gómez-López
- Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico City, México
| | | | - Luisa Rocha
- Pharmacobiology Department, Center for Research and Advanced Studies, México City, México
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3
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Misganaw D. Heteromerization of dopaminergic receptors in the brain: Pharmacological implications. Pharmacol Res 2021; 170:105600. [PMID: 33836279 DOI: 10.1016/j.phrs.2021.105600] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/17/2021] [Accepted: 04/02/2021] [Indexed: 12/15/2022]
Abstract
Dopamine exerts its physiological effects through two subtypes of receptors, i.e. the receptors of the D1 family (D1R and D5R) and the D2 family (D2R, D3R, and D4R), which differ in their pattern of distribution, affinity, and signaling. The D1-like subfamily (D1R and D5R) are coupled to Gαs/olf proteins to activate adenylyl cyclase whereas the D2-like receptors are coupled to Gαi/o subunits and suppress the activity of adenylyl cyclase. Dopamine receptors are capable of forming homodimers, heterodimers, and higher-order oligomeric complexes, resulting in a change in the individual protomers' recognition, signaling, and pharmacology. Heteromerization has the potential to modify the canonical pharmacological features of individual monomeric units such as ligand affinity, activation, signaling, and cellular trafficking through allosteric interactions, reviving the field and introducing a new pharmacological target. Since heteromers are expressed and formed in a tissue-specific manner, they could provide the framework to design selective and effective drug candidates, such as brain-penetrant heterobivalent drugs and interfering peptides, with limited side effects. Therefore, heteromerization could be a promising area of pharmacology research, as it could contribute to the development of novel pharmacological interventions for dopamine dysregulated brain disorders such as addiction, schizophrenia, cognition, Parkinson's disease, and other motor-related disorders. This review is articulated based on the three criteria established by the International Union of Basic and Clinical Pharmacology for GPCR heterodimers (IUPHAR): evidence of co-localization and physical interactions in native or primary tissue, presence of a new physiological and functional property than the individual protomers, and loss of interaction and functional fingerprints upon heterodimer disruption.
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Affiliation(s)
- Desye Misganaw
- Pharmacology and Toxicology Unit, Department of Pharmacy, College of Medicine and Health Science, Wollo University, P.O. Box 1145, Dessie, Ethiopia.
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Lai TH, Schröder S, Toussaint M, Dukić-Stefanović S, Kranz M, Ludwig FA, Fischer S, Steinbach J, Deuther-Conrad W, Brust P, Moldovan RP. Development of 18F-Labeled Radiotracers for PET Imaging of the Adenosine A 2A Receptor: Synthesis, Radiolabeling and Preliminary Biological Evaluation. Int J Mol Sci 2021; 22:ijms22052285. [PMID: 33669003 PMCID: PMC7956753 DOI: 10.3390/ijms22052285] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 02/21/2021] [Accepted: 02/22/2021] [Indexed: 12/19/2022] Open
Abstract
The adenosine A2A receptor (A2AR) represents a potential therapeutic target for neurodegenerative diseases. Aiming at the development of a positron emission tomography (PET) radiotracer to monitor changes of receptor density and/or occupancy during the A2AR-tailored therapy, we designed a library of fluorinated analogs based on a recently published lead compound (PPY). Among those, the highly affine 4-fluorobenzyl derivate (PPY1; Ki(hA2AR) = 5.3 nM) and the 2-fluorobenzyl derivate (PPY2; Ki(hA2AR) = 2.1 nM) were chosen for 18F-labeling via an alcohol-enhanced copper-mediated procedure starting from the corresponding boronic acid pinacol ester precursors. Investigations of the metabolic stability of [18F]PPY1 and [18F]PPY2 in CD-1 mice by radio-HPLC analysis revealed parent fractions of more than 76% of total activity in the brain. Specific binding of [18F]PPY2 on mice brain slices was demonstrated by in vitro autoradiography. In vivo PET/magnetic resonance imaging (MRI) studies in CD-1 mice revealed a reasonable high initial brain uptake for both radiotracers, followed by a fast clearance.
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Affiliation(s)
- Thu Hang Lai
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (M.T.); (S.D.-S.); (M.K.); (F.-A.L.); (S.F.); (J.S.); (W.D.-C.); (P.B.)
- Department of Research and Development, ROTOP Pharmaka Ltd., Dresden 01328, Germany;
- Correspondence: (T.H.L.); (R.-P.M.); Tel.: +49-341-234-179-4635 (T.H.L.); +49-341-234-179-4634 (R.-P.M.)
| | - Susann Schröder
- Department of Research and Development, ROTOP Pharmaka Ltd., Dresden 01328, Germany;
| | - Magali Toussaint
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (M.T.); (S.D.-S.); (M.K.); (F.-A.L.); (S.F.); (J.S.); (W.D.-C.); (P.B.)
| | - Sladjana Dukić-Stefanović
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (M.T.); (S.D.-S.); (M.K.); (F.-A.L.); (S.F.); (J.S.); (W.D.-C.); (P.B.)
| | - Mathias Kranz
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (M.T.); (S.D.-S.); (M.K.); (F.-A.L.); (S.F.); (J.S.); (W.D.-C.); (P.B.)
- PET Imaging Center, University Hospital of North Norway (UNN), 9009 Tromsø, Norway
- Nuclear Medicine and Radiation Biology Research Group, The Arctic University of Norway, 9009 Tromsø, Norway
| | - Friedrich-Alexander Ludwig
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (M.T.); (S.D.-S.); (M.K.); (F.-A.L.); (S.F.); (J.S.); (W.D.-C.); (P.B.)
| | - Steffen Fischer
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (M.T.); (S.D.-S.); (M.K.); (F.-A.L.); (S.F.); (J.S.); (W.D.-C.); (P.B.)
| | - Jörg Steinbach
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (M.T.); (S.D.-S.); (M.K.); (F.-A.L.); (S.F.); (J.S.); (W.D.-C.); (P.B.)
- Department of Research and Development, ROTOP Pharmaka Ltd., Dresden 01328, Germany;
| | - Winnie Deuther-Conrad
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (M.T.); (S.D.-S.); (M.K.); (F.-A.L.); (S.F.); (J.S.); (W.D.-C.); (P.B.)
| | - Peter Brust
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (M.T.); (S.D.-S.); (M.K.); (F.-A.L.); (S.F.); (J.S.); (W.D.-C.); (P.B.)
| | - Rareş-Petru Moldovan
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (M.T.); (S.D.-S.); (M.K.); (F.-A.L.); (S.F.); (J.S.); (W.D.-C.); (P.B.)
- Correspondence: (T.H.L.); (R.-P.M.); Tel.: +49-341-234-179-4635 (T.H.L.); +49-341-234-179-4634 (R.-P.M.)
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5
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Lai TH, Toussaint M, Teodoro R, Dukić-Stefanović S, Kranz M, Deuther-Conrad W, Moldovan RP, Brust P. Synthesis and Biological Evaluation of a Novel 18F-Labeled Radiotracer for PET Imaging of the Adenosine A 2A Receptor. Int J Mol Sci 2021; 22:ijms22031182. [PMID: 33504051 PMCID: PMC7865263 DOI: 10.3390/ijms22031182] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/14/2021] [Accepted: 01/18/2021] [Indexed: 02/06/2023] Open
Abstract
The adenosine A2A receptor (A2AR) has emerged as a potential non-dopaminergic target for the treatment of Parkinson’s disease and, thus, the non-invasive imaging with positron emission tomography (PET) is of utmost importance to monitor the receptor expression and occupancy during an A2AR-tailored therapy. Aiming at the development of a PET radiotracer, we herein report the design of a series of novel fluorinated analogs (TOZ1-TOZ7) based on the structure of the A2AR antagonist tozadenant, and the preclinical evaluation of [18F]TOZ1. Autoradiography proved A2AR-specific in vitro binding of [18F]TOZ1 to striatum of mouse and pig brain. Investigations of the metabolic stability in mice revealed parent fractions of more than 76% and 92% of total activity in plasma and brain samples, respectively. Dynamic PET/magnetic resonance imaging (MRI) studies in mice revealed a brain uptake but no A2AR-specific in vivo binding.
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Affiliation(s)
- Thu Hang Lai
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (S.D.-S.); (M.K.); (W.D.-C.); (R.-P.M.); (P.B.)
- Department of Research and Development, ROTOP Pharmaka Ltd., 01328 Dresden, Germany
- Correspondence: (T.H.L.); (M.T.); Tel.: +49-341-234-179-4635 (T.H.L.); +49-341-234-179-4616 (M.T.)
| | - Magali Toussaint
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (S.D.-S.); (M.K.); (W.D.-C.); (R.-P.M.); (P.B.)
- Correspondence: (T.H.L.); (M.T.); Tel.: +49-341-234-179-4635 (T.H.L.); +49-341-234-179-4616 (M.T.)
| | - Rodrigo Teodoro
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (S.D.-S.); (M.K.); (W.D.-C.); (R.-P.M.); (P.B.)
| | - Sladjana Dukić-Stefanović
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (S.D.-S.); (M.K.); (W.D.-C.); (R.-P.M.); (P.B.)
| | - Mathias Kranz
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (S.D.-S.); (M.K.); (W.D.-C.); (R.-P.M.); (P.B.)
- PET Imaging Center, University Hospital of North Norway (UNN), 9009 Tromsø, Norway
- Nuclear Medicine and Radiation Biology Research Group, The Arctic University of Norway, 9009 Tromsø, Norway
| | - Winnie Deuther-Conrad
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (S.D.-S.); (M.K.); (W.D.-C.); (R.-P.M.); (P.B.)
| | - Rareş-Petru Moldovan
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (S.D.-S.); (M.K.); (W.D.-C.); (R.-P.M.); (P.B.)
| | - Peter Brust
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (S.D.-S.); (M.K.); (W.D.-C.); (R.-P.M.); (P.B.)
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6
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Borroto-Escuela DO, Fuxe K. Adenosine heteroreceptor complexes in the basal ganglia are implicated in Parkinson's disease and its treatment. J Neural Transm (Vienna) 2019; 126:455-471. [PMID: 30637481 PMCID: PMC6456481 DOI: 10.1007/s00702-019-01969-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 01/06/2019] [Indexed: 02/08/2023]
Abstract
The adenosine homo, iso and heteroreceptor complexes in the basal ganglia play a highly significant role in modulating the indirect and direct pathways and the striosomal projections to the nigro-striatal DA system. The major adenosine receptor complexes in the striato-pallidal GABA neurons can be the A2AR-D2R and A2AR-D2R-mGluR5 receptor complexes, in which A2AR protomers and mGluR5 protomers can allosterically interact to inhibit D2R protomer signaling. Through a reorganization of these heteroreceptor complexes upon chronic dopaminergic treatment a pathological and prolonged inhibition of D2R receptor protomer signaling can develop with motor inhibition and wearing off of the therapeutic effects of levodopa and dopamine receptor agonists. The direct pathway is enriched in D1R in and around glutamate synapses enhancing the ability of these GABA neurons to be activated and increase motor initiation. The brake on these GABA neurons is in this case exerted by A1R forming A1R-D1R heteroreceptor complexes in which they allosterically inhibit D1R signaling and thereby reduce motor initiation. Upon chronic levodopa treatment a reorganization of the D1R heteroreceptor complexes develops with the formation of putative A1R-D1R-D3 in addition to D1R-D3R complexes in which D3R enhances D1R protomer signaling and may make the A1R protomer brake less effective. Alpha-synuclein monomers-dimers are postulated to form complexes with A2AR homo and heteroprotomers in the plasma membrane enhancing alpha-synuclein aggregation and toxicity. The alpha-synuclein fibrils formed in the A2AR enriched dendritic spines of the striato-pallidal GABA neurons may reach the surrounding DA terminals via extracellular-vesicle-mediated volume transmission involving internalization of the vesicles and their cargo (alpha-synuclein fibrils) into the vulnerable DA terminals, enhancing their degeneration followed by retrograde flow of these fibrils in the DA axons to the vulnerable nigral DA nerve cells.
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Affiliation(s)
- Dasiel O. Borroto-Escuela
- Department of Neuroscience, Karolinska Institutet, Biomedicum, B0851, Solnavägen 9, 17177 Stockholm, Sweden
- Observatorio Cubano de Neurociencias, Grupo Bohío-Estudio, Zayas 50, 62100 Yaguajay, Cuba
| | - Kjell Fuxe
- Department of Neuroscience, Karolinska Institutet, Biomedicum, B0851, Solnavägen 9, 17177 Stockholm, Sweden
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Guidolin D, Marcoli M, Tortorella C, Maura G, Agnati LF. Receptor-Receptor Interactions as a Widespread Phenomenon: Novel Targets for Drug Development? Front Endocrinol (Lausanne) 2019; 10:53. [PMID: 30833931 PMCID: PMC6387912 DOI: 10.3389/fendo.2019.00053] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 01/21/2019] [Indexed: 12/19/2022] Open
Abstract
The discovery of receptor-receptor interactions (RRI) has expanded our understanding of the role that G protein-coupled receptors (GPCRs) play in intercellular communication. The finding that GPCRs can operate as receptor complexes, and not only as monomers, suggests that several different incoming signals could already be integrated at the plasma membrane level via direct allosteric interactions between the protomers that form the complex. Most research in this field has focused on neuronal populations and has led to the identification of a large number of RRI. However, RRI have been seen to occur not only in neurons but also in astrocytes and, outside the central nervous system, in cells of the cardiovascular and endocrine systems and in cancer cells. Furthermore, RRI involving the formation of macromolecular complexes are not limited to GPCRs, being also observed in other families of receptors. Thus, RRI appear as a widespread phenomenon and oligomerization as a common mechanism for receptor function and regulation. The discovery of these macromolecular assemblies may well have a major impact on pharmacology. Indeed, the formation of receptor complexes significantly broadens the spectrum of mechanisms available to receptors for recognition and signaling, which may be implemented through modulation of the binding sites of the adjacent protomers and of their signal transduction features. In this context, the possible appearance of novel allosteric sites in the receptor complex structure may be of particular relevance. Thus, the existence of RRI offers the possibility of new therapeutic approaches, and novel pharmacological strategies for disease treatment have already been proposed. Several challenges, however, remain. These include the accurate characterization of the role that the receptor complexes identified so far play in pathological conditions and the development of ligands specific to given receptor complexes, in order to efficiently exploit the pharmacological properties of these complexes.
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Affiliation(s)
- Diego Guidolin
- Department of Neuroscience, University of Padova, Padova, Italy
- *Correspondence: Diego Guidolin
| | - Manuela Marcoli
- Department of Pharmacy and Center of Excellence for Biomedical Research, University of Genova, Genoa, Italy
| | | | - Guido Maura
- Department of Pharmacy and Center of Excellence for Biomedical Research, University of Genova, Genoa, Italy
| | - Luigi F. Agnati
- Department of Biomedical Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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8
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Borroto-Escuela DO, Wydra K, Filip M, Fuxe K. A2AR-D2R Heteroreceptor Complexes in Cocaine Reward and Addiction. Trends Pharmacol Sci 2018; 39:1008-1020. [PMID: 30384981 DOI: 10.1016/j.tips.2018.10.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 09/10/2018] [Accepted: 10/08/2018] [Indexed: 12/29/2022]
Abstract
The concept of allosteric receptor-receptor interactions in G protein-coupled receptor homo- and heteroreceptor complexes in which they physically interact provides a new dimension to molecular integration in the brain. The receptor-receptor interactions dynamically change recognition, pharmacology, signaling, and trafficking of the participating receptors. Among the receptor complexes, disruption of the A2A receptor-dopamine D2 receptor (A2AR-D2R) complex by an A2AR agonist has been shown to fully block the inhibition of cocaine self-administration. Cocaine induced pathological A2AR-D2R-Sigma1R complexes may form a long-term memory with a strong and permanent D2R brake, leading to cocaine addiction. These heteroreceptor complexes can potentially be targeted for future pharmacotherapy of cocaine addiction by using heterobivalent compounds or A2AR-D2R receptor interface-interfering peptides that disrupt the A2AR-D2R-Sigma1R complexes.
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Affiliation(s)
| | - Karolina Wydra
- Institute of Pharmacology, Polish Academy of Sciences, Department of Drug Addiction Pharmacology, Smetna, Kraków, Poland
| | - Malgorzata Filip
- Institute of Pharmacology, Polish Academy of Sciences, Department of Drug Addiction Pharmacology, Smetna, Kraków, Poland
| | - Kjell Fuxe
- Department of Neuroscience, Karolinska Institutet, Solnavägen 9, Stockholm, Sweden.
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9
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Guidolin D, Marcoli M, Tortorella C, Maura G, Agnati LF. G protein-coupled receptor-receptor interactions give integrative dynamics to intercellular communication. Rev Neurosci 2018; 29:703-726. [DOI: 10.1515/revneuro-2017-0087] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 01/01/2018] [Indexed: 01/14/2023]
Abstract
Abstract
The proposal of receptor-receptor interactions (RRIs) in the early 1980s broadened the view on the role of G protein-coupled receptors (GPCR) in the dynamics of the intercellular communication. RRIs, indeed, allow GPCR to operate not only as monomers but also as receptor complexes, in which the integration of the incoming signals depends on the number, spatial arrangement, and order of activation of the protomers forming the complex. The main biochemical mechanisms controlling the functional interplay of GPCR in the receptor complexes are direct allosteric interactions between protomer domains. The formation of these macromolecular assemblies has several physiologic implications in terms of the modulation of the signaling pathways and interaction with other membrane proteins. It also impacts on the emerging field of connectomics, as it contributes to set and tune the synaptic strength. Furthermore, recent evidence suggests that the transfer of GPCR and GPCR complexes between cells via the exosome pathway could enable the target cells to recognize/decode transmitters and/or modulators for which they did not express the pertinent receptors. Thus, this process may also open the possibility of a new type of redeployment of neural circuits. The fundamental aspects of GPCR complex formation and function are the focus of the present review article.
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Affiliation(s)
- Diego Guidolin
- Department of Neuroscience , University of Padova, via Gabelli 65 , I-35121 Padova , Italy
| | - Manuela Marcoli
- Department of Pharmacy and Center of Excellence for Biomedical Research , University of Genova , I-16126 Genova , Italy
| | - Cinzia Tortorella
- Department of Neuroscience , University of Padova, via Gabelli 65 , I-35121 Padova , Italy
| | - Guido Maura
- Department of Pharmacy and Center of Excellence for Biomedical Research , University of Genova , I-16126 Genova , Italy
| | - Luigi F. Agnati
- Department of Biomedical Sciences , University of Modena and Reggio Emilia , I-41121 Modena , Italy
- Department of Neuroscience , Karolinska Institutet , S-17177 Stockholm , Sweden
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10
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Nazario LR, da Silva RS, Bonan CD. Targeting Adenosine Signaling in Parkinson's Disease: From Pharmacological to Non-pharmacological Approaches. Front Neurosci 2017; 11:658. [PMID: 29217998 PMCID: PMC5703841 DOI: 10.3389/fnins.2017.00658] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 11/10/2017] [Indexed: 12/29/2022] Open
Abstract
Parkinson's disease (PD) is one of the most prevalent neurodegenerative disease displaying negative impacts on both the health and social ability of patients and considerable economical costs. The classical anti-parkinsonian drugs based in dopaminergic replacement are the standard treatment, but several motor side effects emerge during long-term use. This mini-review presents the rationale to several efforts from pre-clinical and clinical studies using adenosine receptor antagonists as a non-dopaminergic therapy. As several studies have indicated that the monotherapy with adenosine receptor antagonists reaches limited efficacy, the usage as a co-adjuvant appeared to be a promising strategy. The formulation of multi-targeted drugs, using adenosine receptor antagonists and other neurotransmitter systems than the dopaminergic one as targets, have been receiving attention since Parkinson's disease presents a complex biological impact. While pharmacological approaches to cure or ameliorate the conditions of PD are the leading strategy in this area, emerging positive aspects have arisen from non-pharmacological approaches and adenosine function inhibition appears to improve both strategies.
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Affiliation(s)
- Luiza R Nazario
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil
| | - Rosane S da Silva
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil
| | - Carla D Bonan
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil
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Understanding the Functional Plasticity in Neural Networks of the Basal Ganglia in Cocaine Use Disorder: A Role for Allosteric Receptor-Receptor Interactions in A2A-D2 Heteroreceptor Complexes. Neural Plast 2016; 2016:4827268. [PMID: 27872762 PMCID: PMC5107220 DOI: 10.1155/2016/4827268] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 08/28/2016] [Accepted: 10/03/2016] [Indexed: 11/17/2022] Open
Abstract
Our hypothesis is that allosteric receptor-receptor interactions in homo- and heteroreceptor complexes may form the molecular basis of learning and memory. This principle is illustrated by showing how cocaine abuse can alter the adenosine A2AR-dopamine D2R heterocomplexes and their receptor-receptor interactions and hereby induce neural plasticity in the basal ganglia. Studies with A2AR ligands using cocaine self-administration procedures indicate that antagonistic allosteric A2AR-D2R heterocomplexes of the ventral striatopallidal GABA antireward pathway play a significant role in reducing cocaine induced reward, motivation, and cocaine seeking. Anticocaine actions of A2AR agonists can also be produced at A2AR homocomplexes in these antireward neurons, actions in which are independent of D2R signaling. At the A2AR-D2R heterocomplex, they are dependent on the strength of the antagonistic allosteric A2AR-D2R interaction and the number of A2AR-D2R and A2AR-D2R-sigma1R heterocomplexes present in the ventral striatopallidal GABA neurons. It involves a differential cocaine-induced increase in sigma1Rs in the ventral versus the dorsal striatum. In contrast, the allosteric brake on the D2R protomer signaling in the A2AR-D2R heterocomplex of the dorsal striatopallidal GABA neurons is lost upon cocaine self-administration. This is potentially due to differences in composition and allosteric plasticity of these complexes versus those in the ventral striatopallidal neurons.
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Navarro G, Borroto-Escuela DO, Fuxe K, Franco R. Purinergic signaling in Parkinson's disease. Relevance for treatment. Neuropharmacology 2015. [PMID: 26211977 DOI: 10.1016/j.neuropharm.2015.07.024] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Purinergic signaling modulates dopaminergic neurotransmission in health and disease. Classically adenosine A1 and A2A receptors have been considered key for the fine tune control of dopamine actions in the striatum, the main CNS motor control center. The main adenosine signaling mechanism is via the cAMP pathway but the future will tell whether calcium signaling is relevant in adenosinergic control of striatal function. Very relevant is the recent approval in Japan of the adenosine A2A receptor antagonist, istradefylline, for use in Parkinson's disease patients. Purine nucleotides are also regulators of striatal dopamine neurotransmission via P2 purinergic receptors. In parallel to the alpha-synuclein hypothesis of Parkinson's disease etiology, purinergic P2X1 receptors have been identified as mediators of accumulation of the Lewy-body enriched protein alpha-synuclein. Of note is the expression in striatum of purinergic-receptor-containing heteromers that are potential targets of anti-Parkinson's disease therapies and should be taken into account in drug discovery programs. This article is part of the Special Issue entitled 'Purines in Neurodegeneration and Neuroregeneration'.
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Affiliation(s)
- Gemma Navarro
- Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain; Centro de Investigación en Red, Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.
| | - Dasiel O Borroto-Escuela
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden; Department of Earth, Life and Environmental Sciences, Section of Physiology, Campus Scientifico Enrico Mattei, University of Urbino, Urbino, Italy.
| | - Kjell Fuxe
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
| | - Rafael Franco
- Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain; Centro de Investigación en Red, Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.
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Guidolin D, Agnati LF, Marcoli M, Borroto-Escuela DO, Fuxe K. G-protein-coupled receptor type A heteromers as an emerging therapeutic target. Expert Opin Ther Targets 2014; 19:265-83. [PMID: 25381716 DOI: 10.1517/14728222.2014.981155] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION The discovery of receptor-receptor interactions (RRIs) in the early 1980s provided evidence that G-protein-coupled receptors (GPCRs) operate not only as monomers but also as heteromers, in which integration of the incoming signals takes place already at the plasma membrane level through allosteric RRIs. These integrative mechanisms give sophisticated dynamics to the structure and function of these receptor assemblies in terms of modulation of recognition, G-protein signaling and selectivity and switching to β-arrestin signaling. AREAS COVERED The present review briefly describes the concept of direct RRI and the available data on the mechanisms of oligomer formation. Further, pharmacological data concerning the best characterized heteromers involving type A GPCRs will be analyzed to evaluate their profile as possible targets for the treatment of various diseases, in particular of impacting diseases of the CNS. EXPERT OPINION GPCR heteromers have the potential to open a completely new field for pharmacology with likely a major impact in molecular medicine. Novel pharmacological strategies for the treatment of several pathologies have already been proposed. However, several challenges still exist to accurately characterize the role of the identified heteroreceptor complexes in pathology and to develop heteromer-specific ligands capable of efficiently exploiting their pharmacological features.
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Affiliation(s)
- Diego Guidolin
- University of Padova, Department of Molecular Medicine , via Gabelli 65, 35121 Padova , Italy +39 049 8272316 ; +39 049 8272319 ;
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Hasbi A, Perreault ML, Shen MYF, Zhang L, To R, Fan T, Nguyen T, Ji X, O'Dowd BF, George SR. A peptide targeting an interaction interface disrupts the dopamine D1-D2 receptor heteromer to block signaling and function in vitro and in vivo: effective selective antagonism. FASEB J 2014; 28:4806-20. [PMID: 25063849 DOI: 10.1096/fj.14-254037] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Although the dopamine D1-D2 receptor heteromer has emerging physiological relevance and a postulated role in different neuropsychiatric disorders, such as drug addiction, depression, and schizophrenia, there is a need for pharmacological tools that selectively target such receptor complexes in order to analyze their biological and pathophysiological functions. Since no selective antagonists for the D1-D2 heteromer are available, serial deletions and point mutations were used to precisely identify the amino acids involved in an interaction interface between the receptors, residing within the carboxyl tail of the D1 receptor that interacted with the D2 receptor to form the D1-D2 receptor heteromer. It was determined that D1 receptor carboxyl tail residues (404)Glu and (405)Glu were critical in mediating the interaction with the D2 receptor. Isolated mutation of these residues in the D1 receptor resulted in the loss of agonist activation of the calcium signaling pathway mediated through the D1-D2 receptor heteromer. The physical interaction between the D1 and D2 receptor could be disrupted, as shown by coimmunoprecipitation and BRET analysis, by a small peptide generated from the D1 receptor sequence that contained these amino acids, leading to a switch in G-protein affinities and loss of calcium signaling, resulting in the inhibition of D1-D2 heteromer function. The use of the D1-D2 heteromer-disrupting peptide in vivo revealed a pathophysiological role for the D1-D2 heteromer in the modulation of behavioral despair. This peptide may represent a novel pharmacological tool with potential therapeutic benefits in depression treatment.
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Affiliation(s)
- Ahmed Hasbi
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; and Department of Pharmacology and
| | - Melissa L Perreault
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; and Department of Pharmacology and
| | - Maurice Y F Shen
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; and Department of Pharmacology and
| | | | - Ryan To
- Department of Pharmacology and
| | - Theresa Fan
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; and Department of Pharmacology and
| | - Tuan Nguyen
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; and Department of Pharmacology and
| | | | - Brian F O'Dowd
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; and Department of Pharmacology and
| | - Susan R George
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; and Department of Pharmacology and Department of Medicine, University of Toronto, Toronto, Ontario, Canada
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Fuxe K, Borroto-Escuela DO, Romero-Fernandez W, Palkovits M, Tarakanov AO, Ciruela F, Agnati LF. Moonlighting proteins and protein-protein interactions as neurotherapeutic targets in the G protein-coupled receptor field. Neuropsychopharmacology 2014; 39:131-55. [PMID: 24105074 PMCID: PMC3857668 DOI: 10.1038/npp.2013.242] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 07/04/2013] [Accepted: 07/05/2013] [Indexed: 12/28/2022]
Abstract
There is serious interest in understanding the dynamics of the receptor-receptor and receptor-protein interactions in space and time and their integration in GPCR heteroreceptor complexes of the CNS. Moonlighting proteins are special multifunctional proteins because they perform multiple autonomous, often unrelated, functions without partitioning into different protein domains. Moonlighting through receptor oligomerization can be operationally defined as an allosteric receptor-receptor interaction, which leads to novel functions of at least one receptor protomer. GPCR-mediated signaling is a more complicated process than previously described as every GPCR and GPCR heteroreceptor complex requires a set of G protein interacting proteins, which interacts with the receptor in an orchestrated spatio-temporal fashion. GPCR heteroreceptor complexes with allosteric receptor-receptor interactions operating through the receptor interface have become major integrative centers at the molecular level and their receptor protomers act as moonlighting proteins. The GPCR heteroreceptor complexes in the CNS have become exciting new targets for neurotherapeutics in Parkinson's disease, schizophrenia, drug addiction, and anxiety and depression opening a new field in neuropsychopharmacology.
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Affiliation(s)
- Kjell Fuxe
- Department of Neuroscience, Karolinska Institutet,, Stockholm, Sweden
| | | | | | - Miklós Palkovits
- Department of Anatomy, Histology and Embryology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - Alexander O Tarakanov
- Russian Academy of Sciences, St. Petersburg Institute for Informatics and Automation, Saint Petersburg, Russia
| | - Francisco Ciruela
- Facultat de Medicina, Departament de Patologia i Terapèutica Experimental IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Unitat de Farmacologia, Barcelona, Spain
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On the g-protein-coupled receptor heteromers and their allosteric receptor-receptor interactions in the central nervous system: focus on their role in pain modulation. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:563716. [PMID: 23956775 PMCID: PMC3730365 DOI: 10.1155/2013/563716] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 05/20/2013] [Accepted: 05/24/2013] [Indexed: 12/16/2022]
Abstract
The modulatory role of allosteric receptor-receptor interactions in the pain pathways of the Central Nervous System and the peripheral nociceptors has become of increasing interest. As integrators of nociceptive and antinociceptive wiring and volume transmission signals, with a major role for the opioid receptor heteromers, they likely have an important role in the pain circuits and may be involved in acupuncture. The delta opioid receptor (DOR) exerts an antagonistic allosteric influence on the mu opioid receptor (MOR) function in a MOR-DOR heteromer. This heteromer contributes to morphine-induced tolerance and dependence, since it becomes abundant and develops a reduced G-protein-coupling with reduced signaling mainly operating via β-arrestin2 upon chronic morphine treatment. A DOR antagonist causes a return of the Gi/o binding and coupling to the heteromer and the biological actions of morphine. The gender- and ovarian steroid-dependent recruitment of spinal cord MOR/kappa opioid receptor (KOR) heterodimers enhances antinociceptive functions and if impaired could contribute to chronic pain states in women. MOR1D heterodimerizes with gastrin-releasing peptide receptor (GRPR) in the spinal cord, mediating morphine induced itch. Other mechanism for the antinociceptive actions of acupuncture along meridians may be that it enhances the cross-desensitization of the TRPA1 (chemical nociceptor)-TRPV1 (capsaicin receptor) heteromeric channel complexes within the nociceptor terminals located along these meridians. Selective ionotropic cannabinoids may also produce cross-desensitization of the TRPA1-TRPV1 heteromeric nociceptor channels by being negative allosteric modulators of these channels leading to antinociception and antihyperalgesia.
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Agnati LF, Guidolin D, Vilardaga JP, Ciruela F, Fuxe K. On the expanding terminology in the GPCR field: the meaning of receptor mosaics and receptor heteromers. J Recept Signal Transduct Res 2010; 30:287-303. [PMID: 20429829 PMCID: PMC3595533 DOI: 10.3109/10799891003786226] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The oligomerization of G protein-coupled receptors (GPCRs) is a fact that deserves further attention as increases both the complexity and diversity of the receptor-mediated signal transduction, thus enriching the cell signaling. Consequently, in the present review we tackle among others the problems concerning the terminology used to describe aspects surrounding the GPCRs oligomerization phenomenon. Therefore, the theoretical implications of the GPCR oligomerization will be briefly discussed together with possible implications of this phenomenon especially for new strategies in drug development.
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Adenosine-dopamine interactions in the pathophysiology and treatment of CNS disorders. CNS Neurosci Ther 2010; 16:e18-42. [PMID: 20345970 DOI: 10.1111/j.1755-5949.2009.00126.x] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Adenosine-dopamine interactions in the central nervous system (CNS) have been studied for many years in view of their relevance for disorders of the CNS and their treatments. The discovery of adenosine and dopamine receptor containing receptor mosaics (RM, higher-order receptor heteromers) in the striatum opened up a new understanding of these interactions. Initial findings indicated the existence of A(2A)R-D(2)R heterodimers and A(1)R-D(1)R heterodimers in the striatum that were followed by indications for the existence of striatal A(2A)R-D(3)R and A(2A)R-D(4)R heterodimers. Of particular interest was the demonstration that antagonistic allosteric A(2A)-D(2) and A(1)-D(1) receptor-receptor interactions take place in striatal A(2A)R-D(2)R and A(1)R-D(1)R heteromers. As a consequence, additional characterization of these heterodimers led to new aspects on the pathophysiology of Parkinson's disease (PD), schizophrenia, drug addiction, and l-DOPA-induced dyskinesias relevant for their treatments. In fact, A(2A)R antagonists were introduced in the symptomatic treatment of PD in view of the discovery of the antagonistic A(2A)R-D(2)R interaction in the dorsal striatum that leads to reduced D(2)R recognition and G(i/o) coupling in striato-pallidal GABAergic neurons. In recent years, indications have been obtained that A(2A)R-D(2)R and A(1)R-D(1)R heteromers do not exist as heterodimers, rather as RM. In fact, A(2A)-CB(1)-D(2) RM and A(2A)-D(2)-mGlu(5) RM have been discovered using a sequential BRET-FRET technique and by using the BRET technique in combination with bimolecular fluorescence complementation. Thus, other pathogenic mechanisms beside the well-known alterations in the release and/or decoding of dopamine in the basal ganglia and limbic system are involved in PD, schizophrenia and drug addiction. In fact, alterations in the stoichiometry and/or topology of A(2A)-CB(1)-D(2) and A(2A)-D(2)-mGlu5 RM may play a role. Thus, the integrative receptor-receptor interactions in these RM give novel aspects on the pathophysiology and treatment strategies, based on combined treatments, for PD, schizophrenia, and drug addiction.
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