1
|
Ågren R, Sahlholm K. G protein-coupled receptor kinase-2 confers isoform-specific calcium sensitivity to dopamine D 2 receptor desensitization. FASEB J 2021; 35:e22013. [PMID: 34699610 DOI: 10.1096/fj.202100704rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 10/04/2021] [Accepted: 10/11/2021] [Indexed: 11/11/2022]
Abstract
The dopamine D2 receptor (D2 R) functions as an autoreceptor on dopaminergic cell bodies and terminals and as a postsynaptic receptor on a variety of neurons in the central nervous system. As a result of alternative splicing, the D2 R is expressed as two isoforms: long (D2L R) and short (D2S R) differing by a stretch of 29 residues in the third intracellular loop, with D2S R being the predominant presynaptic isoform. Recent reports described a Ca2+ sensitivity of the desensitization time course of potassium currents elicited via D2S R, but not via D2L R, when either isoform was selectively expressed in dopaminergic neurons. Here, we aimed to study the mechanism behind this subtype-specific Ca2+ sensitivity. Thus, we measured the desensitization of potassium channel responses evoked by D2L R and D2S R using two-electrode voltage clamp in Xenopus oocytes in the absence and presence of different amounts of β-arrestin2 and G protein-coupled receptor kinase-2 (GRK2), both of which are known to play important roles in D2 R desensitization in native cells. We found that co-expression of both GRK2 and β-arrestin2 was necessary for reconstitution of the Ca2+ sensitivity of D2S R desensitization, while D2L R did not display Ca2+ sensitivity under these conditions. The effect of Ca2+ chelation by BAPTA-AM to slow the rate of D2S R desensitization was mimicked by the GRK2 inhibitor, Cmpd101, and by the kinase-inactivating GRK2 mutation, K220R, but not by the PKC inhibitor, Gö6976, nor by the calmodulin antagonist, KN-93. Thus, Ca2+ -sensitive desensitization of D2S R appears to be mediated via a GRK2 phosphorylation-dependent mechanism.
Collapse
Affiliation(s)
- Richard Ågren
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Kristoffer Sahlholm
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Integrative Medical Biology, Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Sweden
| |
Collapse
|
2
|
Dopamine D 2 Receptor Agonist Binding Kinetics-Role of a Conserved Serine Residue. Int J Mol Sci 2021; 22:ijms22084078. [PMID: 33920848 PMCID: PMC8071183 DOI: 10.3390/ijms22084078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/06/2021] [Accepted: 04/13/2021] [Indexed: 01/03/2023] Open
Abstract
The forward (kon) and reverse (koff) rate constants of drug–target interactions have important implications for therapeutic efficacy. Hence, time-resolved assays capable of measuring these binding rate constants may be informative to drug discovery efforts. Here, we used an ion channel activation assay to estimate the kons and koffs of four dopamine D2 receptor (D2R) agonists; dopamine (DA), p-tyramine, (R)- and (S)-5-OH-dipropylaminotetralin (DPAT). We further probed the role of the conserved serine S1935.42 by mutagenesis, taking advantage of the preferential interaction of (S)-, but not (R)-5-OH-DPAT with this residue. Results suggested similar koffs for the two 5-OH-DPAT enantiomers at wild-type (WT) D2R, both being slower than the koffs of DA and p-tyramine. Conversely, the kon of (S)-5-OH-DPAT was estimated to be higher than that of (R)-5-OH-DPAT, in agreement with the higher potency of the (S)-enantiomer. Furthermore, S1935.42A mutation lowered the kon of (S)-5-OH-DPAT and reduced the potency difference between the two 5-OH-DPAT enantiomers. Kinetic Kds derived from the koff and kon estimates correlated well with EC50 values for all four compounds across four orders of magnitude, strengthening the notion that our assay captured meaningful information about binding kinetics. The approach presented here may thus prove valuable for characterizing D2R agonist candidate drugs.
Collapse
|
3
|
Wesołowska A, Jastrzębska-Więsek M, Cios A, Partyka A. The preclinical discovery and development of paliperidone for the treatment of schizophrenia. Expert Opin Drug Discov 2019; 15:279-292. [DOI: 10.1080/17460441.2020.1682994] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Anna Wesołowska
- Jagiellonian University Medical College, Department of Clinical Pharmacy, Kraków, Poland
| | | | - Agnieszka Cios
- Jagiellonian University Medical College, Department of Clinical Pharmacy, Kraków, Poland
| | - Anna Partyka
- Jagiellonian University Medical College, Department of Clinical Pharmacy, Kraków, Poland
| |
Collapse
|
4
|
De Vries L, Finana F, Cathala C, Ronsin B, Cussac D. Innovative Bioluminescence Resonance Energy Transfer Assay Reveals Differential Agonist-Induced D2 Receptor Intracellular Trafficking and Arrestin-3 Recruitment. Mol Pharmacol 2019; 96:308-319. [PMID: 31266815 DOI: 10.1124/mol.119.115998] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 06/19/2019] [Indexed: 01/14/2023] Open
Abstract
The dopamine D2 receptor (D2R) mediates ligand-biased signaling with potential therapeutic implications. However, internalization, choice of endocytic routes, and degradation of the D2R in lysosomes may also participate in agonist-directed trafficking. We developed bioluminescence resonance energy transfer (BRET) assays that measure relative distances between Renilla luciferase8-tagged D2R and green fluorescent protein 2 (GFP2)-tagged K-Ras (plasma membrane marker), and between luciferase8-tagged D2R and GFP2-Rab5 (early), GFP2-Rab4 (recycling), or GFP2-Rab7 (late) endosomal markers. The BRET signal between D2R-Luc and GFP2-K-Ras was robustly diminished after receptor internalization induced by dopamine, with subsequent BRET signals increasing when luciferase8-tagged D2R approached GFP2-Rab proteins in endosomal compartments. All BRET signals were blocked by the selective D2R antagonist haloperidol and were decreased by low temperature and high sucrose blocks, two parameters interfering with internalization. Some antipsychotic drugs, such as aripiprazole, are less efficacious in internalizing D2R than most of the antiparkinsonian agents. However, antipsychotics were nearly as efficacious as antiparkinsonians in directing the D2R toward early and recycling endosomes. The Rab7 marker for the late endosome/lysosome route was also capable of discriminating between D2R compounds. We could show that some drugs engaged the D2R either to interact preferentially with arrestin-3 or to internalize. Our study revealed that D2R trafficking in cells was differentially regulated by antipsychotic and antiparkinsonian drugs. Taken together, the BRET assays reported here could further help decipher D2R ligand-induced arrestin-3 recruitment and trafficking, with potentially more selective therapeutic profiles and fewer undesired side effects.
Collapse
Affiliation(s)
- Luc De Vries
- Central Nervous System Innovation Unit, CEPC Campans - Belair de Campans, Castres, France (L.D.V., F.F., C.C., D.C.) and CNRS, UMR5547, Centre de Biologie du Développement, Université de Toulouse III-Paul Sabatier, Toulouse, France (B.R.)
| | - Frédéric Finana
- Central Nervous System Innovation Unit, CEPC Campans - Belair de Campans, Castres, France (L.D.V., F.F., C.C., D.C.) and CNRS, UMR5547, Centre de Biologie du Développement, Université de Toulouse III-Paul Sabatier, Toulouse, France (B.R.)
| | - Claudie Cathala
- Central Nervous System Innovation Unit, CEPC Campans - Belair de Campans, Castres, France (L.D.V., F.F., C.C., D.C.) and CNRS, UMR5547, Centre de Biologie du Développement, Université de Toulouse III-Paul Sabatier, Toulouse, France (B.R.)
| | - Brice Ronsin
- Central Nervous System Innovation Unit, CEPC Campans - Belair de Campans, Castres, France (L.D.V., F.F., C.C., D.C.) and CNRS, UMR5547, Centre de Biologie du Développement, Université de Toulouse III-Paul Sabatier, Toulouse, France (B.R.)
| | - Didier Cussac
- Central Nervous System Innovation Unit, CEPC Campans - Belair de Campans, Castres, France (L.D.V., F.F., C.C., D.C.) and CNRS, UMR5547, Centre de Biologie du Développement, Université de Toulouse III-Paul Sabatier, Toulouse, France (B.R.)
| |
Collapse
|
5
|
Gont A, Daneshmand M, Woulfe J, Lavictoire SJ, Lorimer IAJ. PREX1 integrates G protein-coupled receptor and phosphoinositide 3-kinase signaling to promote glioblastoma invasion. Oncotarget 2018; 8:8559-8573. [PMID: 28051998 PMCID: PMC5352422 DOI: 10.18632/oncotarget.14348] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 12/06/2016] [Indexed: 12/17/2022] Open
Abstract
A defining feature of the brain cancer glioblastoma is its highly invasive nature. When glioblastoma cells are isolated from patients using serum free conditions, they accurately recapitulate this invasive behaviour in animal models. The Rac subclass of Rho GTPases has been shown to promote invasive behaviour in glioblastoma cells isolated in this manner. However the guanine nucleotide exchange factors responsible for activating Rac in this context have not been characterized previously. PREX1 is a Rac guanine nucleotide exchange factor that is synergistically activated by binding of G protein αγ subunits and the phosphoinositide 3-kinase pathway second messenger phosphatidylinositol 3,4,5 trisphosphate. This makes it of particular interest in glioblastoma, as the phosphoinositide 3-kinase pathway is aberrantly activated by mutation in almost all cases. We show that PREX1 is expressed in glioblastoma cells isolated under serum-free conditions and in patient biopsies. PREX1 promotes the motility and invasion of glioblastoma cells, promoting Rac-mediated activation of p21-associated kinases and atypical PKC, which have established roles in cell motility. Glioblastoma cell motility was inhibited by either inhibition of phosphoinositide 3-kinase or inhibition of G protein βγ subunits. Motility was also inhibited by the generic dopamine receptor inhibitor haloperidol or a combination of the selective dopamine receptor D2 and D4 inhibitors L-741,626 and L-745,870. This establishes a role for dopamine receptor signaling via G protein βγ subunits in glioblastoma invasion and shows that phosphoinositide 3-kinase mutations in glioblastoma require a context of basal G protein–coupled receptor activity in order to promote this invasion.
Collapse
Affiliation(s)
- Alexander Gont
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, Canada.,Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Manijeh Daneshmand
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, Canada.,Department of Pathology and Laboratory Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - John Woulfe
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, Canada.,Department of Pathology and Laboratory Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Sylvie J Lavictoire
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Ian A J Lorimer
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, Canada.,Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada.,Department of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| |
Collapse
|
6
|
Möller D, Banerjee A, Uzuneser TC, Skultety M, Huth T, Plouffe B, Hübner H, Alzheimer C, Friedland K, Müller CP, Bouvier M, Gmeiner P. Discovery of G Protein-Biased Dopaminergics with a Pyrazolo[1,5-a]pyridine Substructure. J Med Chem 2017; 60:2908-2929. [DOI: 10.1021/acs.jmedchem.6b01857] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Dorothee Möller
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
| | - Ashutosh Banerjee
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
| | - Taygun C. Uzuneser
- Department
of Psychiatry and Psychotherapy, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Marika Skultety
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
| | - Tobias Huth
- Institute
of Physiology and Pathophysiology, Friedrich-Alexander University Erlangen-Nürnberg, Universitätsstraße 17, 91054 Erlangen, Germany
| | - Bianca Plouffe
- Institute
for Research in Immunology and Cancer (IRIC), Department of Biochemistry
and Molecular Medicine, University of Montreal, Québec, Canada H3C 1J4
| | - Harald Hübner
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
| | - Christian Alzheimer
- Institute
of Physiology and Pathophysiology, Friedrich-Alexander University Erlangen-Nürnberg, Universitätsstraße 17, 91054 Erlangen, Germany
| | - Kristina Friedland
- Department
of Chemistry and Pharmacy, Molecular and Clinical Pharmacy, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstraße 4, 91058 Erlangen, Germany
| | - Christian P. Müller
- Department
of Psychiatry and Psychotherapy, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Michel Bouvier
- Institute
for Research in Immunology and Cancer (IRIC), Department of Biochemistry
and Molecular Medicine, University of Montreal, Québec, Canada H3C 1J4
| | - Peter Gmeiner
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
| |
Collapse
|
7
|
Zhang SJ, Sun WW, Yu QY, Cao P, Dong XP, Wu B. Stereoselective synthesis of (−)-3-PPP through palladium-catalysed unactivated C(sp3)–H arylation at the C-3 position of l-pipecolinic acid. Tetrahedron Lett 2017. [DOI: 10.1016/j.tetlet.2016.12.051] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
8
|
Butini S, Nikolic K, Kassel S, Brückmann H, Filipic S, Agbaba D, Gemma S, Brogi S, Brindisi M, Campiani G, Stark H. Polypharmacology of dopamine receptor ligands. Prog Neurobiol 2016; 142:68-103. [PMID: 27234980 DOI: 10.1016/j.pneurobio.2016.03.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 01/26/2016] [Accepted: 03/15/2016] [Indexed: 01/11/2023]
Abstract
Most neurological diseases have a multifactorial nature and the number of molecular mechanisms discovered as underpinning these diseases is continuously evolving. The old concept of developing selective agents for a single target does not fit with the medical need of most neurological diseases. The development of designed multiple ligands holds great promises and appears as the next step in drug development for the treatment of these multifactorial diseases. Dopamine and its five receptor subtypes are intimately involved in numerous neurological disorders. Dopamine receptor ligands display a high degree of cross interactions with many other targets including G-protein coupled receptors, transporters, enzymes and ion channels. For brain disorders like Parkinsońs disease, schizophrenia and depression the dopaminergic system, being intertwined with many other signaling systems, plays a key role in pathogenesis and therapy. The concept of designed multiple ligands and polypharmacology, which perfectly meets the therapeutic needs for these brain disorders, is herein discussed as a general ligand-based concept while focusing on dopaminergic agents and receptor subtypes in particular.
Collapse
Affiliation(s)
- S Butini
- Department of Biotechnology, Chemistry and Pharmacy, European Research Centre for Drug Discovery and Development, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - K Nikolic
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11000 Belgrade, Serbia
| | - S Kassel
- Heinrich Heine University Duesseldorf, Institute of Pharmaceutical and Medicinal Chemistry, Universitaetsstr. 1, 40225 Duesseldorf, Germany
| | - H Brückmann
- Heinrich Heine University Duesseldorf, Institute of Pharmaceutical and Medicinal Chemistry, Universitaetsstr. 1, 40225 Duesseldorf, Germany
| | - S Filipic
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11000 Belgrade, Serbia
| | - D Agbaba
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11000 Belgrade, Serbia
| | - S Gemma
- Department of Biotechnology, Chemistry and Pharmacy, European Research Centre for Drug Discovery and Development, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - S Brogi
- Department of Biotechnology, Chemistry and Pharmacy, European Research Centre for Drug Discovery and Development, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - M Brindisi
- Department of Biotechnology, Chemistry and Pharmacy, European Research Centre for Drug Discovery and Development, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - G Campiani
- Department of Biotechnology, Chemistry and Pharmacy, European Research Centre for Drug Discovery and Development, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - H Stark
- Heinrich Heine University Duesseldorf, Institute of Pharmaceutical and Medicinal Chemistry, Universitaetsstr. 1, 40225 Duesseldorf, Germany.
| |
Collapse
|
9
|
Sahlholm K, Zeberg H, Nilsson J, Ögren SO, Fuxe K, Århem P. The fast-off hypothesis revisited: A functional kinetic study of antipsychotic antagonism of the dopamine D2 receptor. Eur Neuropsychopharmacol 2016; 26:467-76. [PMID: 26811292 DOI: 10.1016/j.euroneuro.2016.01.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 12/02/2015] [Accepted: 01/11/2016] [Indexed: 11/28/2022]
Abstract
Newer, "atypical" antipsychotics carry a lower risk of motor side-effects than older, "typical" compounds. It has been proposed that a ~100-fold faster dissociation from the dopamine D2 receptor (D2R) distinguishes atypical from typical antipsychotics. Furthermore, differing antipsychotic D2R affinities have been suggested to reflect differences in dissociation rate constants (koff), while association rate constants (kon) were assumed to be similar. However, it was recently demonstrated that lipophilic accumulation of ligand in the cell interior and/or membrane can cause underestimation of koff, and as high-affinity D2R antagonists are frequently lipophilic, this may have been a confounding factor in previous studies. In the present work, a functional electrophysiology assay was used to measure the recovery of dopamine-mediated D2R responsivity from antipsychotic antagonism, using elevated concentrations of dopamine to prevent the potential bias of re-binding of lipophilic ligands. The variability of antipsychotic kon was also reexamined, capitalizing on the temporal resolution of the assay. kon was estimated from the experimental recordings using a simple mathematical model assumed to describe the binding process. The time course of recovery from haloperidol (typical antipsychotic) was only 6.4- to 2.5-fold slower than that of the atypical antipsychotics, amisulpride, clozapine, and quetiapine, while antipsychotic kons were found to vary more widely than previously suggested. Finally, affinities calculated using our kon and koff estimates correlated well with functional potency and with affinities reported from radioligand binding studies. In light of these findings, it appears unlikely that typical and atypical antipsychotics are primarily distinguished by their D2R binding kinetics.
Collapse
Affiliation(s)
- Kristoffer Sahlholm
- Department of Neuroscience, Karolinska Institutet, Retzius väg 8, SE-171 77 Stockholm, Sweden.
| | - Hugo Zeberg
- Department of Neuroscience, Karolinska Institutet, Retzius väg 8, SE-171 77 Stockholm, Sweden
| | - Johanna Nilsson
- Department of Neuroscience, Karolinska Institutet, Retzius väg 8, SE-171 77 Stockholm, Sweden
| | - Sven Ove Ögren
- Department of Neuroscience, Karolinska Institutet, Retzius väg 8, SE-171 77 Stockholm, Sweden
| | - Kjell Fuxe
- Department of Neuroscience, Karolinska Institutet, Retzius väg 8, SE-171 77 Stockholm, Sweden
| | - Peter Århem
- Department of Neuroscience, Karolinska Institutet, Retzius väg 8, SE-171 77 Stockholm, Sweden
| |
Collapse
|
10
|
de Bartolomeis A, Tomasetti C, Iasevoli F. Update on the Mechanism of Action of Aripiprazole: Translational Insights into Antipsychotic Strategies Beyond Dopamine Receptor Antagonism. CNS Drugs 2015; 29:773-99. [PMID: 26346901 PMCID: PMC4602118 DOI: 10.1007/s40263-015-0278-3] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Dopamine partial agonism and functional selectivity have been innovative strategies in the pharmacological treatment of schizophrenia and mood disorders and have shifted the concept of dopamine modulation beyond the established approach of dopamine D2 receptor (D2R) antagonism. Despite the fact that aripiprazole was introduced in therapy more than 12 years ago, many questions are still unresolved regarding the complexity of the effects of this agent on signal transduction and intracellular pathways, in part linked to its pleiotropic receptor profile. The complexity of the mechanism of action has progressively shifted the conceptualization of this agent from partial agonism to functional selectivity. From the induction of early genes to modulation of scaffolding proteins and activation of transcription factors, aripiprazole has been shown to affect multiple cellular pathways and several cortical and subcortical neurotransmitter circuitries. Growing evidence shows that, beyond the consequences of D2R occupancy, aripiprazole has a unique neurobiology among available antipsychotics. The effect of chronic administration of aripiprazole on D2R affinity state and number has been especially highlighted, with relevant translational implications for long-term treatment of psychosis. The hypothesized effects of aripiprazole on cell-protective mechanisms and neurite growth, as well as the differential effects on intracellular pathways [i.e. extracellular signal-regulated kinase (ERK)] compared with full D2R antagonists, suggest further exploration of these targets by novel and future biased ligand compounds. This review aims to recapitulate the main neurobiological effects of aripiprazole and discuss the potential implications for upcoming improvements in schizophrenia therapy based on dopamine modulation beyond D2R antagonism.
Collapse
Affiliation(s)
- Andrea de Bartolomeis
- Unit of Treatment Resistant Psychosis, Laboratory of Molecular and Translational Psychiatry, Department of Neuroscience, University School of Medicine of Napoli "Federico II", Via Pansini, 5, Edificio n.18, 3rd floor, 80131, Naples, Italy.
| | - Carmine Tomasetti
- Unit of Treatment Resistant Psychosis, Laboratory of Molecular and Translational Psychiatry, Department of Neuroscience, University School of Medicine of Napoli "Federico II", Via Pansini, 5, Edificio n.18, 3rd floor, 80131, Naples, Italy
| | - Felice Iasevoli
- Unit of Treatment Resistant Psychosis, Laboratory of Molecular and Translational Psychiatry, Department of Neuroscience, University School of Medicine of Napoli "Federico II", Via Pansini, 5, Edificio n.18, 3rd floor, 80131, Naples, Italy
| |
Collapse
|
11
|
The vital role of constitutive GPCR activity in the mesolimbic dopamine system. Transl Psychiatry 2014; 4:e361. [PMID: 24518399 PMCID: PMC3944632 DOI: 10.1038/tp.2013.130] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Revised: 11/13/2013] [Accepted: 12/07/2013] [Indexed: 12/28/2022] Open
Abstract
The midbrain dopamine system has an important role in processing rewards and the stimuli associated with them, and is implicated in various psychiatric disorders. This system is tightly regulated by various G protein-coupled receptors (GPCRs). It is becoming increasingly clear that these receptors are not only activated by (endogenous) agonists but that they also exhibit agonist-independent intrinsic constitutive activity. In this review we highlight the evidence for the physiological role of such constitutive GPCR activity (in particular for cannabinoid 1, serotonin 2C and mu-opioid receptors) in the ventral tegmental area and in its output regions like the nucleus accumbens. We also address the behavioral relevance of constitutive GPCR signaling and discuss the repercussions of its abolition in dopamine-related psychiatric diseases.
Collapse
|
12
|
Typical and atypical antipsychotics do not differ markedly in their reversibility of antagonism of the dopamine D2 receptor. Int J Neuropsychopharmacol 2014; 17:149-55. [PMID: 24074141 DOI: 10.1017/s1461145713000801] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
It has been suggested that the favorable side-effect profiles of atypical antipsychotics (e.g. clozapine and amisulpride) are related to their ∼100-fold faster dissociation from dopamine D2 receptors (D2R) compared with typical antipsychotics (e.g. haloperidol and chlorpromazine). Fast dissociation would entail rapidly reversible antagonism; however, this has not been thoroughly studied using functional assays. We compared the reversibilities of D2R antagonism by 17 compounds using an electrophysiological method to measure dopamine-evoked potassium channel activation via D2R. Varying rates and amplitudes of D2R response recovery were observed following antagonist removal. Whereas recovery rates differed 15-fold between atypical drugs, recovery from clozapine and amisulpride antagonism was, unexpectedly, less than twofold faster than from chlorpromazine. The recovery amplitude correlated with calculated water solubility and lipid/water distribution coefficients, suggesting variable drug partitioning into cell membranes. Our data do not support the notion that the rate of reversibility of D2R antagonism is what distinguishes atypical from typical antipsychotics.
Collapse
|
13
|
Clarke WP, Chavera TA, Silva M, Sullivan LC, Berg KA. Signalling profile differences: paliperidone versus risperidone. Br J Pharmacol 2013; 170:532-45. [PMID: 23826915 PMCID: PMC3791992 DOI: 10.1111/bph.12295] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 06/20/2013] [Accepted: 06/25/2013] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND AND PURPOSE Paliperidone is an active metabolite of the second-generation atypical antipsychotic, risperidone recently approved for the treatment of schizophrenia and schizoaffective disorder. Because paliperidone differs from risperidone by only a single hydroxyl group, questions have been raised as to whether there are significant differences in the effects elicited between these two drugs. EXPERIMENTAL APPROACH We compared the relative efficacies of paliperidone versus risperidone to regulate several cellular signalling pathways coupled to four selected GPCR targets that are important for either therapeutic or adverse effects: human dopamine D2 , human serotonin 2A receptor subtype (5-HT2A ), human serotonin 2C receptor subtype and human histamine H1 receptors. KEY RESULTS Whereas the relative efficacies of paliperidone and risperidone were the same for some responses, significant differences were found for several receptor-signalling systems, with paliperidone having greater or less relative efficacy than risperidone depending upon the receptor-response pair. Interestingly, for 5-HT2A -mediated recruitment of β-arrestin, 5-HT2A -mediated sensitization of ERK, and dopamine D2 -mediated sensitization of adenylyl cyclase signalling, both paliperidone and risperidone behaved as agonists. CONCLUSIONS AND IMPLICATIONS These results suggest that the single hydroxyl group of paliperidone promotes receptor conformations that can differ from those of risperidone leading to differences in the spectrum of regulation of cellular signal transduction cascades. Such differences in signalling at the cellular level could lead to differences between paliperidone and risperidone in therapeutic efficacy or in the generation of adverse effects.
Collapse
MESH Headings
- Adenylyl Cyclases/metabolism
- Animals
- Antipsychotic Agents/chemistry
- Antipsychotic Agents/pharmacology
- Arrestins/metabolism
- CHO Cells
- Cricetinae
- Cricetulus
- Dopamine Agonists/pharmacology
- Dose-Response Relationship, Drug
- Drug Inverse Agonism
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Histamine Agonists/pharmacology
- Humans
- Isoxazoles/chemistry
- Isoxazoles/pharmacology
- Molecular Structure
- Paliperidone Palmitate
- Pyrimidines/chemistry
- Pyrimidines/pharmacology
- Receptor, Serotonin, 5-HT2A/drug effects
- Receptor, Serotonin, 5-HT2A/genetics
- Receptor, Serotonin, 5-HT2A/metabolism
- Receptor, Serotonin, 5-HT2C/drug effects
- Receptor, Serotonin, 5-HT2C/genetics
- Receptor, Serotonin, 5-HT2C/metabolism
- Receptors, Dopamine D2/drug effects
- Receptors, Dopamine D2/genetics
- Receptors, Dopamine D2/metabolism
- Receptors, Histamine H1/drug effects
- Receptors, Histamine H1/genetics
- Receptors, Histamine H1/metabolism
- Risperidone/chemistry
- Risperidone/pharmacology
- Serotonin Receptor Agonists/pharmacology
- Signal Transduction/drug effects
- Structure-Activity Relationship
- Transfection
- beta-Arrestins
Collapse
Affiliation(s)
- W P Clarke
- Department of Pharmacology, University of Texas Health Science Center, San Antonio, TX, USA
| | | | | | | | | |
Collapse
|
14
|
Czoty PW, Gage HD, Garg PK, Garg S, Nader MA. Effects of repeated treatment with the dopamine D2/D3 receptor partial agonist aripiprazole on striatal D2/D3 receptor availability in monkeys. Psychopharmacology (Berl) 2013; 231:10.1007/s00213-013-3274-7. [PMID: 24077804 PMCID: PMC3969775 DOI: 10.1007/s00213-013-3274-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Accepted: 08/29/2013] [Indexed: 01/11/2023]
Abstract
RATIONALE Chronic treatment with dopamine (DA) receptor agonists and antagonists can differentially affect measures of DA D2/D3 receptor number and function, but the effects of chronic treatment with a partial D2/D3 receptor agonist are not clear. OBJECTIVE We used a within-subjects design in male cynomolgus monkeys to determine the effects of repeated (17-day) treatment with the D2/D3 receptor partial agonist aripiprazole (ARI; 0.03 mg/kg and 0.1 mg/kg i.m.) on food-reinforced behavior (n = 5) and on D2/D3 receptor availability as measured with positron emission tomography (PET; n = 9). METHODS Five monkeys responded under a fixed-ratio 50 schedule of food reinforcement and D2/D3 receptor availability was measured before and 4 days after ARI treatment using PET and the D2/D3 receptor-selective radioligand [18F]fluoroclebopride (FCP). Four additional monkeys were studied using [11C]raclopride and treated sequentially with each dose of ARI for 17 days. RESULTS ARI decreased food-maintained responding with minimal evidence of tolerance. Repeated ARI administration increased FCP and raclopride distribution volume ratios (DVRs) in the caudate nucleus and putamen in most monkeys, but decreases were observed in monkeys with the highest baseline DVRs. CONCLUSIONS The results indicate that repeated treatment with a low-efficacy DA receptor partial agonist produces effects on brain D2/D3 receptor availability that are qualitatively different from those of both high-efficacy receptor agonists and antagonists, and suggest that the observed individual differences in response to ARI treatment may reflect its partial agonist activity.
Collapse
Affiliation(s)
- Paul W. Czoty
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1083
| | - H. Donald Gage
- Department of Radiology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1083
| | - Pradeep K. Garg
- Department of Radiology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1083
| | - Sudha Garg
- Department of Radiology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1083
| | - Michael A. Nader
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1083
- Department of Radiology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1083
| |
Collapse
|
15
|
Strange PG. Use of the GTPγS ([35S]GTPγS and Eu-GTPγS) binding assay for analysis of ligand potency and efficacy at G protein-coupled receptors. Br J Pharmacol 2011; 161:1238-49. [PMID: 20662841 DOI: 10.1111/j.1476-5381.2010.00963.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
UNLABELLED In this review I consider assays for G protein-coupled receptor (GPCR) activity based on the binding of labelled analogues of GTPγS ([(35) S]GTPγS or Eu-GTPγS) to G proteins in tissues (GTPγS binding assays). Such assays provide convenient measures of GPCR activity close to the receptor in the signalling cascade. In order to set up a GTPγS binding assay, the requirements of the assay must be considered. These are tissue source, GTPγS analogue, G protein, GDP, Mg(2+) /Na(+) ions, saponin, incubation time. The assay, once optimized, can be used to generate concentration/response curves for GPCRs signalling via G(i/o) proteins (or to other G proteins with a modified assay) and actions of agonists, inverse agonists and antagonists may, in principle, be assessed. For agonists and inverse agonists, data for the maximal agonist effect, the concentration of ligand giving a half-maximal response and the Hill coefficient may be derived. For antagonists, data for the equilibrium dissociation constant can be obtained. The mechanistic basis of the assay is considered. Although the assay can be used to profile ligands, under the conditions it is used, it may not be measuring the same event that determines GPCR action in cells. LINKED ARTICLES This article is part of a themed section on Analytical Receptor Pharmacology in Drug Discovery. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2010.161.issue-6
Collapse
Affiliation(s)
- Philip G Strange
- School of Pharmacy, University of Reading, Whiteknights, Reading, UK.
| |
Collapse
|
16
|
The clozapine metabolite N-desmethylclozapine displays variable activity in diverse functional assays at human dopamine D₂ and serotonin 5-HT₁A receptors. Eur J Pharmacol 2011; 669:51-8. [PMID: 21835172 DOI: 10.1016/j.ejphar.2011.07.031] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 06/28/2011] [Accepted: 07/21/2011] [Indexed: 11/22/2022]
Abstract
N-desmethylclozapine (NDMC or norclozapine) is the major active metabolite of the antipsychotic clozapine in humans. The activity of NDMC differs from clozapine at a number of neurotransmitter receptors, probably influencing the pharmacological effects of clozapine treatment. Here, we tested the properties of NDMC in comparison with clozapine at recombinant human dopamine D(2) and serotonin 5-HT(1A) receptors, using a panel of functional assays implicating diverse signalling pathways. At dopamine D(2) receptors, NDMC as well as clozapine did not display agonist activity in measures of G protein activation by [(35)S]GTPγS binding and in the sensitive Extracellular Signal-Regulated Kinase 1/2 (ERK1/2) phosphorylation assay. In contrast, there were weak partial agonist actions of NDMC (but not of clozapine) for dopamine D(2)-dependent activation of Ca(2+) liberation via coexpressed chimeric Gα(q/o) proteins and for G protein-coupled inward rectifier potassium channel (GIRK) current induction in Xenopus oocytes. Intriguingly, GIRK currents induced by NDMC via dopamine D(2) receptors showed a rapid and transient time course, strikingly different from currents recorded with other receptor agonists. At serotonin 5-HT(1A) receptors, NDMC was a more efficacious partial agonist than clozapine for [(35)S]GTPγS binding, ERK1/2 phosphorylation and GIRK activation. Respective low and moderate partial agonist properties of NDMC at dopamine D(2) and serotonin 5-HT(1A) receptors thus differentiate the metabolite from its parent drug and may contribute to the overall effects of clozapine pharmacotherapy.
Collapse
|
17
|
Comparative pharmacology of antipsychotics possessing combined dopamine D2 and serotonin 5-HT1A receptor properties. Psychopharmacology (Berl) 2011; 216:451-73. [PMID: 21394633 DOI: 10.1007/s00213-011-2247-y] [Citation(s) in RCA: 124] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Accepted: 02/22/2011] [Indexed: 02/07/2023]
Abstract
RATIONALE There is increasing interest in antipsychotics intended to manage positive symptoms via D(2) receptor blockade and improve negative symptoms and cognitive deficits via 5-HT(1A) activation. Such a strategy reduces side-effects such as the extrapyramidal syndrome (EPS), weight gain, and autonomic disturbance liability. OBJECTIVE This study aims to review pharmacological literature on compounds interacting at both 5-HT(1A) and D(2) receptors (as well as at other receptors), including aripiprazole, perospirone, ziprasidone, bifeprunox, lurasidone and cariprazine, PF-217830, adoprazine, SSR181507, and F15063. METHODS We examine data on in vitro binding and agonism and in vivo tests related to (1) positive symptoms (e.g., psychostimulant-induced hyperactivity or prepulse inhibition deficit), (2) negative symptoms (e.g., phencyclidine-induced social interaction deficits and cortical dopamine release), and (3) cognitive deficits (e.g., phencyclidine or scopolamine-induced memory deficits). EPS liability is assessed by measuring catalepsy and neuroendocrine impact by determining plasma prolactin, glucose, and corticosterone levels. RESULTS Compounds possessing "balanced" 5-HT(1A) receptor agonism and D(2) antagonism (or weak partial agonism) and, in some cases, combined with other beneficial properties, such as 5-HT(2A) receptor antagonism, are efficacious in a broad range of rodent pharmacological models yet have a lower propensity to elicit EPS or metabolic dysfunction. CONCLUSIONS Recent compounds exhibiting combined 5-HT(1A)/D(2) properties may be effective in treating a broader range of symptoms of schizophrenia and be better tolerated than existing antipsychotics. Nevertheless, further investigations are necessary to evaluate recent compounds, notably in view of their differing levels of 5-HT(1A) affinity and efficacy, which can markedly influence activity and side-effect profiles.
Collapse
|
18
|
Human kisspeptins activate neuropeptide FF2 receptor. Neuroscience 2010; 170:117-22. [PMID: 20600636 DOI: 10.1016/j.neuroscience.2010.06.058] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 06/02/2010] [Accepted: 06/23/2010] [Indexed: 11/20/2022]
Abstract
We studied the possible activation of a neuropeptide FF2 receptor (NPFF2R) by kisspeptins, neuropeptides derived from the mouse and human metastin or Kiss-1 precursor. The hypothesis was that the human kisspeptins, which share the C-terminal dipeptide RF-NH(2) with NPFF, might activate the NPFF2R, as has previously been shown for two related peptides, prolactin-releasing peptide and RF-amide-related peptide. Using two-electrode voltage clamp of Xenopus oocytes, we found that 100 nM NPFF strongly activated the human NPFF2R expressed together with rat GIRK1/4 inward rectifier potassium channels, and that 100 nM hKisspeptin-13 and hKisspeptin-8 had about 25% relative efficacy to that of NPFF. The current response induced by hKisspeptin-13 was proportional to its concentration (1-500 nM). The corresponding mouse peptides resulted in low activation only. When hNPFF2R was expressed in Chinese hamster ovary (CHO) cells, NPFF and its stable analog (1DMe)Y8Fa induced guanosine 5'-(gamma-[(35)S]thio)-triphosphate (GTP-gamma-[(35)S]) binding with EC(50) values of 13+/-4 and 16+/-4 nM, respectively. hKisspeptin-13 induced the binding with an EC(50) value of 110+/-50 nM, whereas mKisspeptin-13 induced very modestly activation with an EC(50) value>2 microM. The results suggest that, besides regulation of reproduction, kisspeptins have a potential to mediate physiological effects on, for example autonomic regulation and nociception in man via the NPFF2R pathways.
Collapse
|
19
|
Millan MJ. From the cell to the clinic: a comparative review of the partial D₂/D₃receptor agonist and α2-adrenoceptor antagonist, piribedil, in the treatment of Parkinson's disease. Pharmacol Ther 2010; 128:229-73. [PMID: 20600305 DOI: 10.1016/j.pharmthera.2010.06.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/02/2010] [Indexed: 12/16/2022]
Abstract
Though L-3,4-dihydroxyphenylalanine (L-DOPA) is universally employed for alleviation of motor dysfunction in Parkinson's disease (PD), it is poorly-effective against co-morbid symptoms like cognitive impairment and depression. Further, it elicits dyskinesia, its pharmacokinetics are highly variable, and efficacy wanes upon long-term administration. Accordingly, "dopaminergic agonists" are increasingly employed both as adjuncts to L-DOPA and as monotherapy. While all recognize dopamine D(2) receptors, they display contrasting patterns of interaction with other classes of monoaminergic receptor. For example, pramipexole and ropinirole are high efficacy agonists at D(2) and D(3) receptors, while pergolide recognizes D(1), D(2) and D(3) receptors and a broad suite of serotonergic receptors. Interestingly, several antiparkinson drugs display modest efficacy at D(2) receptors. Of these, piribedil displays the unique cellular signature of: 1), signal-specific partial agonist actions at dopamine D(2)and D(3) receptors; 2), antagonist properties at α(2)-adrenoceptors and 3), minimal interaction with serotonergic receptors. Dopamine-deprived striatal D(2) receptors are supersensitive in PD, so partial agonism is sufficient for relief of motor dysfunction while limiting undesirable effects due to "over-dosage" of "normosensitive" D(2) receptors elsewhere. Further, α(2)-adrenoceptor antagonism reinforces adrenergic, dopaminergic and cholinergic transmission to favourably influence motor function, cognition, mood and the integrity of dopaminergic neurones. In reviewing the above issues, the present paper focuses on the distinctive cellular, preclinical and therapeutic profile of piribedil, comparisons to pramipexole, ropinirole and pergolide, and the core triad of symptoms that characterises PD-motor dysfunction, depressed mood and cognitive impairment. The article concludes by highlighting perspectives for clarifying the mechanisms of action of piribedil and other antiparkinson agents, and for optimizing their clinical exploitation.
Collapse
Affiliation(s)
- Mark J Millan
- Dept of Psychopharmacology, Institut de Recherches Servier, 125 Chemin de Ronde, 78290 Croissy/Seine (Paris), France.
| |
Collapse
|
20
|
Heusler P, Rauly-Lestienne I, Tourette A, Tardif S, Ailhaud MC, Croville G, Cussac D. Actions of the prototypical 5-HT1A receptor agonist 8-OH-DPAT at human alpha2-adrenoceptors: (+)8-OH-DPAT, but not (-)8-OH-DPAT is an alpha2B subtype preferential agonist. Eur J Pharmacol 2010; 640:8-14. [PMID: 20450907 DOI: 10.1016/j.ejphar.2010.04.034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 03/22/2010] [Accepted: 04/19/2010] [Indexed: 11/18/2022]
Abstract
8-OH-DPAT [8-hydroxy-2-(di-n-propylamino)tetralin] is the prototypical agonist at serotonin 5-HT1A receptors; however, activity at other targets contributes to the functional effects of the compound as well. We examined the properties of 8-OH-DPAT and its enantiomers at recombinant human (h)alpha2-adrenoceptor subtypes, using a panel of radioligand binding and functional tests. In competition binding experiments using [3H]-RX821002, about 10-fold selectivity of (+)8-OH-DPAT for the halpha2B subtype (pKi about 7) over halpha2A- and halpha2C-adrenoceptors was observed. In contrast, the S(-) enantiomer of 8-OH-DPAT showed similar weak affinities for the three receptor subtypes (pKis<6). The binding affinity of (+)8-OH-DPAT at the halpha2B- and the halpha2A-adrenoceptor was found sensitive to GTPgammaS, a receptor/G protein-uncoupling agent, indicating agonist properties of the drug. Furthermore, using [35S]GTPgammaS binding determination at CHO-halpha2B or CHO-halpha2A cell membranes and G protein coupled inwardly rectifying potassium (GIRK) current recordings in Xenopus oocytes expressing halpha2B, partial agonist activity of (+)8-OH-DPAT at the respective receptors was confirmed in these two different functional assays. Potency of (+)8-OH-DPAT for stimulation of [35S]GTPgammaS incorporation was lower at the halpha2A- than at the halpha2B-adrenoceptor, consistent with binding affinities. Thus, (+)8-OH-DPAT and, as a consequence, racemic (+/-)8-OH-DPAT are partial agonists at halpha2-adrenoceptors with selectivity for the halpha2B subtype, a property that might contribute to the effects of the compound described in native systems.
Collapse
Affiliation(s)
- Peter Heusler
- Department of Cellular and Molecular Biology, Centre de Recherche Pierre Fabre, 17, avenue Jean Moulin, F-81106 Castres Cedex, France.
| | | | | | | | | | | | | |
Collapse
|
21
|
Mailman RB, Murthy V. Third generation antipsychotic drugs: partial agonism or receptor functional selectivity? Curr Pharm Des 2010; 16:488-501. [PMID: 19909227 PMCID: PMC2958217 DOI: 10.2174/138161210790361461] [Citation(s) in RCA: 203] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Accepted: 11/12/2009] [Indexed: 11/22/2022]
Abstract
Functional selectivity is the term that describes drugs that cause markedly different signaling through a single receptor (e.g., full agonist at one pathway and antagonist at a second). It has been widely recognized recently that this phenomenon impacts the understanding of mechanism of action of some drugs, and has relevance to drug discovery. One of the clinical areas where this mechanism has particular importance is in the treatment of schizophrenia. Antipsychotic drugs have been grouped according to both pattern of clinical action and mechanism of action. The original antipsychotic drugs such as chlorpromazine and haloperidol have been called typical or first generation. They cause both antipsychotic actions and many side effects (extrapyramidal and endocrine) that are ascribed to their high affinity dopamine D(2) receptor antagonism. Drugs such as clozapine, olanzapine, risperidone and others were then developed that avoided the neurological side effects (atypical or second generation antipsychotics). These compounds are divided mechanistically into those that are high affinity D(2) and 5-HT(2A) antagonists, and those that also bind with modest affinity to D(2), 5-HT(2A), and many other neuroreceptors. There is one approved third generation drug, aripiprazole, whose actions have been ascribed alternately to either D(2) partial agonism or D(2) functional selectivity. Although partial agonism has been the more widely accepted mechanism, the available data are inconsistent with this mechanism. Conversely, the D(2) functional selectivity hypothesis can accommodate all current data for aripiprazole, and also impacts on discovery compounds that are not pure D(2) antagonists.
Collapse
Affiliation(s)
- Richard B Mailman
- Penn State University College of Medicine - Milton S. Hershey Medical Center Department of Pharmacology. R130 500 University Dr., PO Box 850, Hershey, PA 17033-0850, USA.
| | | |
Collapse
|
22
|
Yang TT, Wang SJ. Aripiprazole and its human metabolite OPC14857 reduce, through a presynaptic mechanism, glutamate release in rat prefrontal cortex: possible relevance to neuroprotective interventions in schizophrenia. Synapse 2009; 62:804-18. [PMID: 18720421 DOI: 10.1002/syn.20548] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Aripiprazole is a novel atypical antipsychotic drug with neuroprotective properties. As excessive glutamate release is now considered to be part of the pathophysiology of schizophrenia, the objective of this study was to use an in vitro assay system to investigate the effect of aripiprazole and its human metabolite OPC14857 on the release of endogenous glutamate from isolated nerve terminals (synaptosomes), freshly prepared from rat prefrontal cortex. Both aripiprazole and OPC13857 potently inhibited 4-aminopyridine (4-AP)-evoked glutamate release in a concentration-dependent manner. Inhibition of glutamate release by aripiprazole and OPC13857 was associated with a reduction of 4AP-evoked Na+ influx and depolarization, as well as downstream elevation of cytoplasmic free calcium concentration mediated via N- and P/Q-type voltage-dependent Ca2+ channels (VDCCs). Release induced by direct Ca2+ entry with Ca2+ ionophore (ionomycin) was unaffected by aripiprazole or OPC13857, indicating that the inhibitory effect of aripiprazole or OPC13857 is not due to directly interfering with the release process at some point subsequent to Ca2+ influx. In addition, the dopamine D2 receptor antagonist haloperidol and the 5-HT 1A receptor antagonist WAY100635 all effectively blocked the aripiprazole or OPC13857-mediated inhibition of 4-AP-evoked glutamate release. Moreover, aripiprazole or OPC13857 modulation of 4-AP-evoked glutamate release appears to involve a protein kinase A (PKA) signaling cascade, insofar as pretreatment of synaptosomes with the PKA inhibitor H89 suppressed the inhibitory effect of aripiprazole or OPC13857. Together, these results suggest that aripiprazole and its human metabolite OPC14857 inhibit glutamate release from rat prefrontocortical nerve terminals, likely by the activation of dopamine D2 and 5-HT 1A receptors, which subsequently results in the reduction of nerve terminal excitability and downstream VDCC activation through a signaling cascade involving PKA. These actions of aripiprazole may contribute to its neuroprotective effect in excitotoxic injury.
Collapse
Affiliation(s)
- Tsung-Tsair Yang
- School of Medicine, Fu Jen Catholic University, Taipei Hsien, Taiwan
| | | |
Collapse
|
23
|
Hazelwood LA, Free RB, Cabrera DM, Skinbjerg M, Sibley DR. Reciprocal modulation of function between the D1 and D2 dopamine receptors and the Na+,K+-ATPase. J Biol Chem 2008; 283:36441-53. [PMID: 18984584 PMCID: PMC2605984 DOI: 10.1074/jbc.m805520200] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2008] [Revised: 10/07/2008] [Indexed: 12/21/2022] Open
Abstract
It is well documented that dopamine can increase or decrease the activity of the Na+,K+-ATPase (NKA, sodium pump) in an organ-specific fashion. This regulation can occur, at least partially, via receptor-mediated second messenger activation and can promote NKA insertion or removal from the plasma membrane. Using co-immunoprecipitation and mass spectrometry, we now show that, in both brain and HEK293T cells, D1 and D2 dopamine receptors (DARs) can exist in a complex with the sodium pump. To determine the impact of NKA on DAR function, biological assays were conducted with NKA and DARs co-expressed in HEK293T cells. In this system, expression of NKA dramatically decreased D1 and D2 DAR densities with a concomitant functional decrease in DAR-mediated regulation of cAMP levels. Interestingly, pharmacological inhibition of endogenous or overexpressed NKA enhanced DAR function without altering receptor number or localization. Similarly, DAR function was also augmented by small interfering RNA reduction of the endogenous NKA. These data suggest that, under basal conditions, NKA negatively regulates DAR function via protein-protein interactions. In reciprocal fashion, expression of DARs decreases endogenous NKA function in the absence of dopamine, implicating DAR proteins as regulators of NKA activity. Notably, dopamine stimulation or pertussis toxin inhibition of D2 receptor signaling did not alter NKA activity, indicating that the D2-mediated decrease in NKA function is dependent upon protein-protein interactions rather than signaling molecules. This evidence for reciprocal regulation between DARs and NKA provides a novel control mechanism for both DAR signaling and cellular ion balance.
Collapse
Affiliation(s)
- Lisa A Hazelwood
- Molecular Neuropharmacology Section, NINDS, National Institutes of Health, Bethesda, Maryland 20892-9405, USA
| | | | | | | | | |
Collapse
|
24
|
Sahlholm K, Nilsson J, Marcellino D, Fuxe K, Århem P. Electrophysiology-based analysis of human histamine H4 receptor pharmacology using GIRK channel coupling in Xenopus oocytes. Eur J Pharmacol 2008; 591:52-8. [DOI: 10.1016/j.ejphar.2008.06.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2007] [Revised: 05/27/2008] [Accepted: 06/05/2008] [Indexed: 11/28/2022]
|
25
|
Newman-Tancredi A, Heusler P, Martel JC, Ormière AM, Leduc N, Cussac D. Agonist and antagonist properties of antipsychotics at human dopamine D4.4 receptors: G-protein activation and K+ channel modulation in transfected cells. Int J Neuropsychopharmacol 2008; 11:293-307. [PMID: 17897483 DOI: 10.1017/s1461145707008061] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Interaction at dopamine D4 receptors may improve cognitive function, which is highly impaired in individuals with schizophrenia, but comparative studies of recent antipsychotics in cellular models of D4 receptor activation are lacking. Here, we report the in-vitro profile of over 30 ligands at recombinant hD4.4 receptors. In [35S]GTPgammaS binding experiments using membranes of CHO-hD4.4 cells, apomorphine, preclamol and the selective D4 agonists, ABT724, CP226269, Ro-10-5824 and PD168077, behaved as partial agonists (Emax 20-60% vs. dopamine), whereas L745870 and RBI257, displayed antagonist properties. The 'conventional' antipsychotic, haloperidol and the 'atypicals', clozapine and risperidone, exhibited antagonist properties, while 'third generation' compounds bifeprunox, SLV313 and F15063, acted as partial agonists (10-30%). Aripiprazole and SSR181507 slightly stimulated [35S]GTPgammaS binding at micromolar concentrations. In Xenopus laevis oocytes co-expressing hD4.4 receptors with G-protein-coupled inwardly rectifying potassium (GIRK) channels, apomorphine, preclamol, ABT724, CP226269, and PD168077 stimulated GIRK currents (Emax 70-80%). The 5-HT1A receptor ligands, WAY100635 and flibanserin, also exhibited partial agonist activity (30% and 15%, respectively). Haloperidol, clozapine, olanzapine and nemonapride did not stimulate GIRK currents, whereas aripiprazole, bifeprunox, SLV313 and F15063, but not SSR181507, exhibited partial agonism (Emax 20-35%). In-vitro responses depended on experimental conditions: increasing NaCl concentration (30 mm to 100 mm) reduced agonist efficacy in [35S]GTPgammaS binding, whereas decreasing the amount of hD4.4 cRNA injected into oocytes (from 2.0 to 0.5 ng/oocyte) reduced agonist efficacy of several compounds. These data indicate that, unlike conventional or 'atypical' antipsychotics, several 'third generation' agents display D4 receptor partial agonism that may be sufficient to influence physiological D4 receptor activity in vivo.
Collapse
|
26
|
Actions of novel agonists, antagonists and antipsychotic agents at recombinant rat 5-HT6 receptors: a comparative study of coupling to G alpha s. Eur J Pharmacol 2008; 588:170-7. [PMID: 18511034 DOI: 10.1016/j.ejphar.2008.04.039] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2008] [Revised: 03/21/2008] [Accepted: 04/11/2008] [Indexed: 01/27/2023]
Abstract
Though 5-HT6 receptors are targets for the treatment of schizophrenia and other psychiatric disorders, the influence of drugs upon signal transduction has not been extensively characterized. Herein, we employed a Scintillation Proximity Assay (SPA)/antibody-immunocapture procedure of coupling to G alpha s to evaluate the interaction of a broad range of novel agonists, antagonists and antipsychotics at rat 5-HT(6) receptors stably expressed in HEK293 cells. Serotonin (pEC(50), 7.7) increased [35S]GTP gamma S binding to G alpha s by ca 2-fold without affecting binding to Gi/o or Gq. LSD (9.2), 5-MeODMT (7.9), 5-CT (7.0) and tryptamine (6.1) were likewise full agonists. In contrast, the novel sulfonyl derivatives, WAY181,187 (9.1) and WAY208,466 (7.8), behaved as partial agonists and attenuated the actions of 5-HT. SB271,046 and SB258,585 abolished activation of G alpha s by 5-HT with pKb values of 10.2 and 9.9, respectively, actions mimicked by the novel antagonist, SB399,885 (10.9). SB271,046 likewise blocked partial agonist properties of WAY181,187 and WAY208,466 with pKb values of 9.8 and 9.0, respectively. 5-HT-stimulated [35S]GTP gamma S binding to G alpha s was antagonised by various antipsychotics including olanzapine (7.8), asenapine (9.1) and SB737,050 (7.8), whereas aripiprazole and bifeprunox were inactive. Further, antagonist properties of clozapine (8.0) were mimicked by its major metabolite, N-desmethylclozapine (7.9). In conclusion, the novel ligands, WAY208,466 and WAY181,187, behaved as partial agonists at 5-HT6 receptors coupled to G alpha s, while SB399,885 was a potent antagonist. Though 5-HT6 receptor blockade is not indispensable for therapeutic efficacy, it may well play a role in the functional actions of certain antipsychotic agents.
Collapse
|
27
|
Heusler P, Newman-Tancredi A, Loock T, Cussac D. Antipsychotics differ in their ability to internalise human dopamine D2S and human serotonin 5-HT1A receptors in HEK293 cells. Eur J Pharmacol 2007; 581:37-46. [PMID: 18190908 DOI: 10.1016/j.ejphar.2007.11.046] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Revised: 11/13/2007] [Accepted: 11/21/2007] [Indexed: 10/22/2022]
Abstract
Antipsychotic drugs act preferentially via dopamine D(2) receptor blockade, but interaction with serotonin 5-HT(1A) receptors has attracted interest as additional target for antipsychotic treatment. As receptor internalisation is considered crucial for drug action, we tested the propensity of antipsychotics to internalise human (h)D(2S) receptors and h5-HT(1A) receptors. Agonist-induced internalisation of hemaglutinin (HA)-tagged hD(2S) and HA-h5-HT(1A) receptors expressed in HEK293 cells was increased by coexpression of G-protein coupled receptor kinase 2 and beta-arrestin2. At the HA-hD(2S) receptor, dopamine, quinpirole and bromocriptine behaved as full agonists, while S(-)-3-(3-hydroxyphenyl)-N-n-propylpiperidine [(-)-3PPP] and sarizotan were partial agonists. The typical antipsychotic, haloperidol, and the atypical compounds, olanzapine, nemonapride, ziprasidone and clozapine did not internalise HA-hD(2S) receptors, whereas aripiprazole potently internalised these receptors (>50% relative efficacy). Among antipsychotics with combined D(2)/5-HT(1A) properties, bifeprunox and (3-exo)-8-benzoyl-N-[[(2S)7-chloro-2,3-dihydro-1,4-benzodioxin-1-yl]methyl]-8-azabicyclo-[3.2.1]octane-3-methanamine (SSR181507) partially internalised HA-hD(2S) receptors, piperazine, 1-(2,3-dihydro-1,4-benzodioxin-5-yl)-4-[[5-(4-fluorophenyl)-3-pyridinyl]methyl (SLV313) and N-[(2,2-dimethyl-2,3-dihydro-benzofuran-7-yloxy)ethyl]-3-(cyclopent-1-enyl)-benzylamine (F15063) were inactive. At the HA-h5-HT(1A) receptor, serotonin, (+)-8-hydroxy-2-(di-n-propylamino)tetralin [(+)-8-OH-DPAT] and sarizotan were full agonists, buspirone acted as partial agonist. (-)-Pindolol showed little activity and no internalising properties were manifested for the 5-HT(1A) receptor antagonist N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]-ethyl]-N-(2-pyridinyl)cyclohexanecarboxamide (WAY100635). Most antipsychotics induced HA-h5-HT(1A) receptor internalisation, with an efficacy rank order: nemonapride>F15063>SSR181507>bifeprunox approximately SLV313 approximately ziprasidone>aripiprazole and potencies: SLV313>SSR181507 approximately F15063>bifeprunox approximately nemonapride approximately aripiprazole>ziprasidone. Interestingly, the internalisation induced by clozapine was only minimal, whereas aripirazole and bifeprunox were more potent for internalisation than for G-protein activation. These different profiles of antipsychotics for receptor internalisation may help to evaluate their potential therapeutic impact in the treatment of schizophrenia.
Collapse
Affiliation(s)
- Peter Heusler
- Cellular and Molecular Biology Department, Pierre Fabre Research Center, F-81106 Castres, France.
| | | | | | | |
Collapse
|
28
|
Tadori Y, Kitagawa H, Forbes RA, McQuade RD, Stark A, Kikuchi T. Differences in agonist/antagonist properties at human dopamine D(2) receptors between aripiprazole, bifeprunox and SDZ 208-912. Eur J Pharmacol 2007; 574:103-11. [PMID: 17692841 DOI: 10.1016/j.ejphar.2007.07.031] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Revised: 06/29/2007] [Accepted: 07/18/2007] [Indexed: 11/22/2022]
Abstract
Aripiprazole is the first dopamine D(2) receptor partial agonist approved for use in schizophrenia and bipolar disorder. Other partial agonists have failed in various stages of development, either for reasons of poor tolerability or lack of efficacy. We conducted an in vitro comparative analysis between aripiprazole, bifeprunox, SDZ 208-912, OPC-4392 and ACR16 in attempt to correlate specific pharmacological properties with clinical outcome. In vitro pharmacological assessment included inhibition of forskolin-stimulated cAMP accumulation and the reversal of this inhibition produced by dopamine in clonal CHO cell lines expressing high and low densities of human dopamine D(2L) and D(2S) receptors. In cells expressing high receptor densities, all drugs except ACR16 predominantly behaved as agonists. However, in cells expressing low receptor densities, all drugs showed significantly lower maximal effects than dopamine. Aripiprazole's intrinsic activity was lower than that observed with bifeprunox and OPC-4392, and higher than that of SDZ 208-912. Aripiprazole's antagonist activity was greater than that of bifeprunox and OPC-4392, and less than that of SDZ 208-912. In conclusion, our data suggests that aripiprazole's unique intrinsic activity profile may account for its demonstrated clinical efficacy in the treatment of both positive and negative symptoms of schizophrenia, as well as its demonstrated low liability for parkinsonism and hyperprolactinemia. A higher degree of intrinsic activity, and lower relative antagonist activity, such as that observed with bifeprunox and OPC-4392 may translate into a clinically suboptimal improvement of positive symptoms. SDZ 208-912's intrinsic activity may be lower than the optimal level needed to minimize extrapyramidal symptoms.
Collapse
Affiliation(s)
- Yoshihiro Tadori
- Quests Research Institute, Otsuka Pharmaceutical Co., Ltd., 463-10 Kagasuno, Kawauchi-cho, Tokushima, 771-0192, Japan.
| | | | | | | | | | | |
Collapse
|