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Baker JG, Summers RJ. Adrenoceptors: Receptors, Ligands and Their Clinical Uses, Molecular Pharmacology and Assays. Handb Exp Pharmacol 2024. [PMID: 38926158 DOI: 10.1007/164_2024_713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024]
Abstract
The nine G protein-coupled adrenoceptor subtypes are where the endogenous catecholamines adrenaline and noradrenaline interact with cells. Since they are important therapeutic targets, over a century of effort has been put into developing drugs that modify their activity. This chapter provides an outline of how we have arrived at current knowledge of the receptors, their physiological roles and the methods used to develop ligands. Initial studies in vivo and in vitro with isolated organs and tissues progressed to cell-based techniques and the use of cloned adrenoceptor subtypes together with high-throughput assays that allow close examination of receptors and their signalling pathways. The crystal structures of many of the adrenoceptor subtypes have now been determined opening up new possibilities for drug development.
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Affiliation(s)
- Jillian G Baker
- Cell Signalling, Medical School, Queen's Medical Centre, University of Nottingham, Nottingham, UK.
- Department of Respiratory Medicine, Nottingham University Hospitals NHS Trust, Nottingham, UK.
| | - Roger J Summers
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia.
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2
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Szabo B. Presynaptic Adrenoceptors. Handb Exp Pharmacol 2024. [PMID: 38755350 DOI: 10.1007/164_2024_714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
Presynaptic α2-adrenoceptors are localized on axon terminals of many noradrenergic and non-noradrenergic neurons in the peripheral and central nervous systems. Their activation by exogenous agonists leads to inhibition of the exocytotic release of noradrenaline and other transmitters from the neurons. Most often, the α2A-receptor subtype is involved in this inhibition. The chain of molecular events between receptor occupation and inhibition of the exocytotic release of transmitters has been determined. Physiologically released endogenous noradrenaline elicits retrograde autoinhibition of its own release. Some clonidine-like α2-receptor agonists have been used to treat hypertension. Dexmedetomidine is used for prolonged sedation in the intensive care; It also has a strong analgesic effect. The α2-receptor antagonist mirtazapine increases the noradrenaline concentration in the synaptic cleft by interrupting physiological autoinhibion of release. It belongs to the most effective antidepressive drugs. β2-Adrenoceptors are also localized on axon terminals in the peripheral and central nervous systems. Their activation leads to enhanced transmitter release, however, they are not activated by endogenous adrenaline.
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Affiliation(s)
- Bela Szabo
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany.
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3
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DelaCuesta-Barrutia J, Martínez-Peula O, Rivero G, Santas-Martín JA, Munarriz-Cuezva E, Brocos-Mosquera I, Miranda-Azpiazu P, Diez-Alarcia R, Morentin B, Honer WG, Callado LF, Erdozain AM, Ramos-Miguel A. Effect of antipsychotic drugs on group II metabotropic glutamate receptor expression and epigenetic control in postmortem brains of schizophrenia subjects. Transl Psychiatry 2024; 14:113. [PMID: 38396013 PMCID: PMC10891050 DOI: 10.1038/s41398-024-02832-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 02/07/2024] [Accepted: 02/13/2024] [Indexed: 02/25/2024] Open
Abstract
Antipsychotic-induced low availability of group II metabotropic glutamate receptors (including mGlu2R and mGlu3R) in brains of schizophrenia patients may explain the limited efficacy of mGlu2/3R ligands in clinical trials. Studies evaluating mGlu2/3R levels in well-designed, large postmortem brain cohorts are needed to address this issue. Postmortem samples from the dorsolateral prefrontal cortex of 96 schizophrenia subjects and matched controls were collected. Toxicological analyses identified cases who were (AP+) or were not (AP-) receiving antipsychotic treatment near the time of death. Protein and mRNA levels of mGlu2R and mGlu3R, as well as GRM2 and GRM3 promoter-attached histone posttranslational modifications, were quantified. Experimental animal models were used to compare with data obtained in human tissues. Compared to matched controls, schizophrenia cortical samples had lower mGlu2R protein amounts, regardless of antipsychotic medication. Downregulation of mGlu3R was observed in AP- schizophrenia subjects only. Greater predicted occupancy values of dopamine D2 and serotonin 5HT2A receptors correlated with higher density of mGlu3R, but not mGlu2R. Clozapine treatment and maternal immune activation in rodents mimicked the mGlu2R, but not mGlu3R regulation observed in schizophrenia brains. mGlu2R and mGlu3R mRNA levels, and the epigenetic control mechanisms did not parallel the alterations at the protein level, and in some groups correlated inversely. Insufficient cortical availability of mGlu2R and mGlu3R may be associated with schizophrenia. Antipsychotic treatment may normalize mGlu3R, but not mGlu2R protein levels. A model in which epigenetic feedback mechanisms controlling mGlu3R expression are activated to counterbalance mGluR loss of function is described.
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Affiliation(s)
| | | | - Guadalupe Rivero
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Spain
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain
| | - Jon A Santas-Martín
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Spain
| | - Eva Munarriz-Cuezva
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain
| | - Iria Brocos-Mosquera
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Spain
| | | | - Rebeca Diez-Alarcia
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Spain
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain
| | - Benito Morentin
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
- Basque Institute of Legal Medicine, Bilbao, Spain
| | - William G Honer
- Department Psychiatry, University of British Columbia, Vancouver, BC, Canada
| | - Luis F Callado
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Spain
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain
| | - Amaia M Erdozain
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain
| | - Alfredo Ramos-Miguel
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Spain.
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain.
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain.
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4
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Howard P, Curtin J. Efficacy and safety of subcutaneous clonidine for refractory symptoms in palliative medicine: a retrospective study. BMJ Support Palliat Care 2024; 13:e820-e824. [PMID: 35772835 DOI: 10.1136/spcare-2022-003651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 06/13/2022] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To investigate the efficacy and safety of subcutaneous clonidine for refractory symptoms in the palliative setting. METHODS A retrospective chart review of the use of subcutaneous clonidine in a single palliative care centre. We reviewed the use of clonidine since it was introduced in our locality 2½ years ago. All clinical notes, medication administration records and infusion monitoring documentation were examined to ascertain therapeutic aim, efficacy and tolerability. RESULTS Subcutaneous clonidine was administered to 113 patients. Recipients were generally frail (median Karnofsky Score 20%) and in the last weeks of life (median survival 6 days). The the most common indications were opioid poorly responsive pain (59), agitation refractory to antipsychotics and/or benzodiazepines (18) or both (35). Symptoms appeared to improve in the majority (85/113, 75%). Some (36, 32%) required no further medication changes once clonidine was commenced. Clonidine appeared well tolerated although blood pressure was not monitored in the majority, in line with our practice to discontinue such observations in those who are nursed in bed and receiving symptom-focused care. CONCLUSIONS Subcutaneous administration of clonidine appears to be a promising alternative option for refractory symptoms in the last weeks of life. We suggest some possible next steps for further research.
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Affiliation(s)
- Paul Howard
- Mountbatten Hospice, Newport, Isle of Wight, UK
- Palliative Care Team, Isle of Wight NHS Trust, Newport, Isle of Wight, UK
| | - John Curtin
- Mountbatten Hospice, Newport, Isle of Wight, UK
- Palliative Care Team, Isle of Wight NHS Trust, Newport, Isle of Wight, UK
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5
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Stanford SC, Heal DJ. Adrenoceptors: A Focus on Psychiatric Disorders and Their Treatments. Handb Exp Pharmacol 2023. [PMID: 37495853 DOI: 10.1007/164_2023_675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
Abstract
Research into the involvement of adrenoceptor subtypes in the cause(s) of psychiatric disorders is particularly challenging. This is partly because of difficulties in developing animal models that recapitulate the human condition but also because no evidence for any causal links has emerged from studies of patients. These, and other obstacles, are outlined in this chapter. Nevertheless, many drugs that are used to treat psychiatric disorders bind to adrenoceptors to some extent. Direct or indirect modulation of the function of specific adrenoceptor subtypes mediates all or part of the therapeutic actions of drugs in various psychiatric disorders. On the other hand, interactions with central or peripheral adrenoceptors can also explain their side effects. This chapter discusses both aspects of the field, focusing on disorders that are prevalent: depression, schizophrenia, anxiety, attention-deficit hyperactivity disorder, binge-eating disorder, and substance use disorder. In so doing, we highlight some unanswered questions that need to be resolved before it will be feasible to explain how changes in the function of any adrenoceptor subtype affect mood and behavior in humans and other animals.
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Affiliation(s)
- S Clare Stanford
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK.
| | - David J Heal
- DevelRx Ltd, BioCity, Nottingham, UK
- Department of Life Sciences, University of Bath, Bath, UK
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6
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Brocos-Mosquera I, Miranda-Azpiazu P, Muguruza C, Corzo-Monje V, Morentin B, Meana JJ, Callado LF, Rivero G. Differential brain ADRA2A and ADRA2C gene expression and epigenetic regulation in schizophrenia. Effect of antipsychotic drug treatment. Transl Psychiatry 2021; 11:643. [PMID: 34930904 PMCID: PMC8688495 DOI: 10.1038/s41398-021-01762-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 11/26/2021] [Accepted: 12/01/2021] [Indexed: 01/19/2023] Open
Abstract
Postsynaptic α2A-adrenoceptor density is enhanced in the dorsolateral prefrontal cortex (DLPFC) of antipsychotic-treated schizophrenia subjects. This alteration might be due to transcriptional activation, and could be regulated by epigenetic mechanisms such as histone posttranslational modifications (PTMs). The aim of this study was to evaluate ADRA2A and ADRA2C gene expression (codifying for α2-adrenoceptor subtypes), and permissive and repressive histone PTMs at gene promoter regions in the DLPFC of subjects with schizophrenia and matched controls (n = 24 pairs). We studied the effect of antipsychotic (AP) treatment in AP-free (n = 12) and AP-treated (n = 12) subgroups of schizophrenia subjects and in rats acutely and chronically treated with typical and atypical antipsychotics. ADRA2A mRNA expression was selectively upregulated in AP-treated schizophrenia subjects (+93%) whereas ADRA2C mRNA expression was upregulated in all schizophrenia subjects (+53%) regardless of antipsychotic treatment. Acute and chronic clozapine treatment in rats did not alter brain cortex Adra2a mRNA expression but increased Adra2c mRNA expression. Both ADRA2A and ADRA2C promoter regions showed epigenetic modification by histone methylation and acetylation in human DLPFC. The upregulation of ADRA2A expression in AP-treated schizophrenia subjects might be related to observed bivalent chromatin at ADRA2A promoter region in schizophrenia (depicted by increased permissive H3K4me3 and repressive H3K27me3) and could be triggered by the enhanced H4K16ac at ADRA2A promoter. In conclusion, epigenetic predisposition differentially modulated ADRA2A and ADRA2C mRNA expression in DLPFC of schizophrenia subjects.
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Affiliation(s)
- Iria Brocos-Mosquera
- grid.11480.3c0000000121671098Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia Spain ,grid.469673.90000 0004 5901 7501Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain
| | - Patricia Miranda-Azpiazu
- grid.11480.3c0000000121671098Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia Spain ,grid.469673.90000 0004 5901 7501Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain
| | - Carolina Muguruza
- grid.11480.3c0000000121671098Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia Spain ,grid.469673.90000 0004 5901 7501Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain
| | - Virginia Corzo-Monje
- grid.11480.3c0000000121671098Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia Spain
| | - Benito Morentin
- Section of Forensic Pathology, Basque Institute of Legal Medicine, Bilbao, Spain ,grid.452310.1Biocruces Bizkaia Health Research Institute, Barakaldo, Bizkaia Spain
| | - J. Javier Meana
- grid.11480.3c0000000121671098Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia Spain ,grid.469673.90000 0004 5901 7501Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain ,grid.452310.1Biocruces Bizkaia Health Research Institute, Barakaldo, Bizkaia Spain
| | - Luis F. Callado
- grid.11480.3c0000000121671098Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia Spain ,grid.469673.90000 0004 5901 7501Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain ,grid.452310.1Biocruces Bizkaia Health Research Institute, Barakaldo, Bizkaia Spain
| | - Guadalupe Rivero
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain. .,Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Leioa, Spain. .,Biocruces Bizkaia Health Research Institute, Barakaldo, Bizkaia, Spain.
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7
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Brocos-Mosquera I, Gabilondo AM, Diez-Alarcia R, Muguruza C, Erdozain AM, Meana JJ, Callado LF. α 2A- and α 2C-adrenoceptor expression and functionality in postmortem prefrontal cortex of schizophrenia subjects. Eur Neuropsychopharmacol 2021; 52:3-11. [PMID: 34237656 DOI: 10.1016/j.euroneuro.2021.05.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 04/28/2021] [Accepted: 05/26/2021] [Indexed: 12/25/2022]
Abstract
Previous evidence suggests that α2-adrenoceptors (α2-AR) may be involved in the pathophysiology of schizophrenia. However, postmortem brain studies on α2-AR expression and functionality in schizophrenia are scarce. The aim of our work was to evaluate α2A-AR and α2C-AR expression in different subcellular fractions of prefrontal cortex postmortem tissue from antipsychotic-free (absence of antipsychotics in blood at the time of death) (n = 12) and antipsychotic-treated (n = 12) subjects with schizophrenia, and matched controls (n = 24). Functional coupling of α2-AR to Gα proteins induced by the agonist UK14304 was also tested. Additionally, Gα protein expression was also evaluated. In antipsychotic-free schizophrenia subjects, α2A-AR and α2C-AR protein expression was similar to controls in all the subcellular fractions. Conversely, in antipsychotic-treated schizophrenia subjects, increased α2A-AR expression was found in synaptosomal plasma membrane and postsynaptic density (PSD) fractions (+60% and +79% vs controls, respectively) with no significant changes in α2C-AR. [35S]GTPγS SPA experiments showed a significant lower stimulation of Gαi2 and Gαi3 proteins by UK14304 in antipsychotic-treated schizophrenia subjects, whereas stimulation in antipsychotic-free schizophrenia subjects remained unchanged. Gαo protein stimulation was significantly decreased in both antipsychotic-free and antipsychotic-treated schizophrenia subjects compared to controls. Expression of Gαi3 protein did not differ between groups, whereas Gαi2 levels were increased in PSD of schizophrenia subjects, both antipsychotic-free and antipsychotic-treated. Gαo protein expression was increased in PSD of antipsychotic-treated subjects and in the presynaptic fraction of antipsychotic-free schizophrenia subjects. The present results suggest that antipsychotic treatment is able to modify in opposite directions both the protein expression and the functionality of α2A-AR in the cortex of schizophrenia patients.
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Affiliation(s)
- Iria Brocos-Mosquera
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
| | - Ane M Gabilondo
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain; Biocruces Bizkaia Health Research Institute, Barakaldo, Bizkaia, Spain
| | - Rebeca Diez-Alarcia
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain; Biocruces Bizkaia Health Research Institute, Barakaldo, Bizkaia, Spain
| | - Carolina Muguruza
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
| | - Amaia M Erdozain
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
| | - J Javier Meana
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain; Biocruces Bizkaia Health Research Institute, Barakaldo, Bizkaia, Spain
| | - Luis F Callado
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain; Biocruces Bizkaia Health Research Institute, Barakaldo, Bizkaia, Spain.
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8
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Heteromerization between α 2A adrenoceptors and different polymorphic variants of the dopamine D 4 receptor determines pharmacological and functional differences. Implications for impulsive-control disorders. Pharmacol Res 2021; 170:105745. [PMID: 34182128 PMCID: PMC9885860 DOI: 10.1016/j.phrs.2021.105745] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/11/2021] [Accepted: 06/23/2021] [Indexed: 02/01/2023]
Abstract
Polymorphic alleles of the human dopamine D4 receptor gene (DRD4) have been consistently associated with individual differences in personality traits and neuropsychiatric disorders, particularly between the gene encoding dopamine D4.7 receptor variant and attention deficit hyperactivity disorder (ADHD). The α2A adrenoceptor gene has also been associated with ADHD. In fact, drugs targeting the α2A adrenoceptor (α2AR), such as guanfacine, are commonly used in ADHD treatment. In view of the involvement of dopamine D4 receptor (D4R) and α2AR in ADHD and impulsivity, their concurrent localization in cortical pyramidal neurons and the demonstrated ability of D4R to form functional heteromers with other G protein-coupled receptors, in this study we evaluate whether the α2AR forms functional heteromers with D4R and weather these heteromers show different properties depending on the D4R variant involved. Using cortical brain slices from hD4.7R knock-in and wild-type mice, here, we demonstrate that α2AR and D4R heteromerize and constitute a significant functional population of cortical α2AR and D4R. Moreover, in cortical slices from wild-type mice and in cells transfected with α2AR and D4.4R, we detect a negative crosstalk within the heteromer. This negative crosstalk is lost in cortex from hD4.7R knock-in mice and in cells expressing the D4.7R polymorphic variant. We also show a lack of efficacy of D4R ligands to promote G protein activation and signaling only within the α2AR-D4.7R heteromer. Taken together, our results suggest that α2AR-D4R heteromers play a pivotal role in catecholaminergic signaling in the brain cortex and are likely targets for ADHD pharmacotherapy.
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Mather M. Noradrenaline in the aging brain: Promoting cognitive reserve or accelerating Alzheimer's disease? Semin Cell Dev Biol 2021; 116:108-124. [PMID: 34099360 PMCID: PMC8292227 DOI: 10.1016/j.semcdb.2021.05.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 05/04/2021] [Accepted: 05/05/2021] [Indexed: 12/19/2022]
Abstract
Many believe that engaging in novel and mentally challenging activities promotes brain health and prevents Alzheimer's disease in later life. However, mental stimulation may also have risks as well as benefits. As neurons release neurotransmitters, they often also release amyloid peptides and tau proteins into the extracellular space. These by-products of neural activity can aggregate into the tau tangle and amyloid plaque signatures of Alzheimer's disease. Over time, more active brain regions accumulate more pathology. Thus, increasing brain activity can have a cost. But the neuromodulator noradrenaline, released during novel and mentally stimulating events, may have some protective effects-as well as some negative effects. Via its inhibitory and excitatory effects on neurons and microglia, noradrenaline sometimes prevents and sometimes accelerates the production and accumulation of amyloid-β and tau in various brain regions. Both α2A- and β-adrenergic receptors influence amyloid-β production and tau hyperphosphorylation. Adrenergic activity also influences clearance of amyloid-β and tau. Furthermore, some findings suggest that Alzheimer's disease increases noradrenergic activity, at least in its early phases. Because older brains clear the by-products of synaptic activity less effectively, increased synaptic activity in the older brain risks accelerating the accumulation of Alzheimer's pathology more than it does in the younger brain.
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Affiliation(s)
- Mara Mather
- Leonard Davis School of Gerontology, Department of Psychology, & Department of Biomedical Engineering, University of Southern California, 3715 McClintock Ave, Los Angeles, CA 90089, United States.
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10
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Brocos-Mosquera I, Gabilondo AM, Meana JJ, Callado LF, Erdozain AM. Spinophilin expression in postmortem prefrontal cortex of schizophrenic subjects: Effects of antipsychotic treatment. Eur Neuropsychopharmacol 2021; 42:12-21. [PMID: 33257116 DOI: 10.1016/j.euroneuro.2020.11.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 11/04/2020] [Accepted: 11/11/2020] [Indexed: 10/22/2022]
Abstract
Schizophrenia has been associated with alterations in neurotransmission and synaptic dysfunction. Spinophilin is a multifunctional scaffold protein that modulates excitatory synaptic transmission and dendritic spine morphology. Spinophilin can also directly interact with and regulate several receptors for neurotransmitters, such as dopamine D2 receptors, which play a role in the pathophysiology of schizophrenia and are targets of antipsychotics. Several studies have thus suggested an implication of spinophilin in schizophrenia. In the present study spinophilin protein expression was determined by western blot in the postmortem dorsolateral prefrontal cortex of 24 subjects with schizophrenia (12 antipsychotic-free and 12 antipsychotic-treated subjects) and 24 matched controls. Experiments were performed in synaptosomal membranes (SPM) and in postsynaptic density fractions (PSD). As previously reported, two specific bands for this protein were observed: an upper 120-130 kDa band and a lower 80-95 kDa band. The spinophilin lower band showed a significant decrease in schizophrenia subjects compared to matched controls, both in SPM and PSD fractions (-15%, p = 0.007 and -15%, p = 0.039, respectively). When schizophrenia subjects were divided by the presence or absence of antipsychotics in blood at death, the lower band showed a significant decrease in antipsychotic-treated schizophrenia subjects (-24%, p = 0.003 for SPM and -26%, p = 0.014 for PSD), but not in antipsychotic-free subjects, compared to their matched controls. These results suggest that antipsychotics could produce alterations in spinophilin expression that do not seem to be related to schizophrenia per se. These changes may underlie some of the side effects of antipsychotics.
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Affiliation(s)
- Iria Brocos-Mosquera
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
| | - Ane M Gabilondo
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain; Biocruces Bizkaia Health Research Institute, Barakaldo, Bizkaia, Spain
| | - J Javier Meana
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain; Biocruces Bizkaia Health Research Institute, Barakaldo, Bizkaia, Spain
| | - Luis F Callado
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain; Biocruces Bizkaia Health Research Institute, Barakaldo, Bizkaia, Spain
| | - Amaia M Erdozain
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain.
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11
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Odagaki Y, Kinoshita M, Javier Meana J, Callado LF, García-Sevilla JA. Fundamental features of receptor-mediated Gα i/o activation in human prefrontal cortical membranes: A postmortem study. Brain Res 2020; 1747:147032. [PMID: 32745659 DOI: 10.1016/j.brainres.2020.147032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 07/12/2020] [Accepted: 07/23/2020] [Indexed: 11/19/2022]
Abstract
To elucidate possible abnormalities in transmembrane signal transduction in psychiatric diseases, use of autopsy brain is a feasible approach. However, postmortem studies should be interpreted with caution concerning such factors as age, gender, psychotropic drug history, agonal state, postmortem delay (PMD), and storage period. In this study, agonist-induced [35S]GTPγS binding was performed in postmortem dorsolateral prefrontal cortical membranes of 40 control subjects. In addition to the previously reported G protein-coupled receptor (GPCR)-mediated Gi/o activation, κ-opioid receptor-mediated [35S]GTPγS binding was detected by using U-50,448. The responses elicited by 16 different agonists were determined, and the effects of several factors were investigated. Gender difference was negligible. Concentration-response curve of histamine H3 receptor-mediated [35S]GTPγS binding was shifted rightward in the subjects with some drugs detected at toxicological screening. Age-related alterations were minimal, except for the age-dependent supersensitivity of μ-opioid receptor-mediated Gαi/o activation, revealed by endomorphin-1- and DAMGO-stimulated [35S]GTPγS binding. Age-related increase in %Emax values was also detected as to DPDPE-induced [35S]GTPγS binding through δ-opioid receptors. With an exception of NOP receptor/G-protein coupling, GPCR-mediated [35S]GTPγS binding is relatively stable irrespective of PMD or storage period. There were many positive correlations among the %Emax values for different receptor subtypes, which might reflect formation of heterodimer complex of such GPCRs coupled to the same Gi/o proteins. These results provide us with important fundamental data in the future project using human postmortem brains from patients with psychiatric disorders.
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Affiliation(s)
- Yuji Odagaki
- Department of Psychiatry, Faculty of Medicine, Saitama Medical University, 38 Morohongo, Moroyama-machi, Iruma-gun, Saitama 350-0495, Japan.
| | - Masakazu Kinoshita
- Department of Psychiatry, Faculty of Medicine, Saitama Medical University, 38 Morohongo, Moroyama-machi, Iruma-gun, Saitama 350-0495, Japan
| | - J Javier Meana
- Department of Pharmacology, University of the Basque Country, UPV/EHU, E-48940 Leioa, Bizkaia, and Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain
| | - Luis F Callado
- Department of Pharmacology, University of the Basque Country, UPV/EHU, E-48940 Leioa, Bizkaia, and Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Spain
| | - Jesús A García-Sevilla
- Laboratory of Neuropharmacology, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), University of the Balearic Islands (UIB), and Institut d'investigació Sanitària Illes Balears (IdISBa), Palma de Mallorca, Spain
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Hjorth S, Waters S, Waters N, Tedroff J, Svensson P, Fagerberg A, Edling M, Svanberg B, Ljung E, Gunnergren J, McLean S, Grayson B, Idris N, Neill J, Sonesson C. (3S)‐3‐(2,3‐difluorophenyl)‐3‐methoxypyrrolidine (IRL752) —a Novel Cortical-Preferring Catecholamine Transmission- and Cognition-Promoting Agent. J Pharmacol Exp Ther 2020; 374:404-419. [DOI: 10.1124/jpet.120.000037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 06/25/2020] [Indexed: 12/30/2022] Open
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