1
|
Seillier A. Inhibition of fatty acid amide hydrolase reverses aberrant prefrontal gamma oscillations in the sub-chronic PCP model for schizophrenia. Exp Brain Res 2024; 242:1149-1160. [PMID: 38489023 DOI: 10.1007/s00221-024-06801-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 02/08/2024] [Indexed: 03/17/2024]
Abstract
Hypofunctioning of NMDA receptors, and the resulting shift in the balance between excitation and inhibition, is considered a key process in the pathophysiology of schizophrenia. One important manifestation of this phenomenon is changes in neural oscillations, those above 30 Hz (i.e., gamma-band oscillations), in particular. Although both preclinical and clinical studies observed increased gamma activity following acute administration of NMDA receptor antagonists, the relevance of this phenomenon has been recently questioned given the reduced gamma oscillations typically observed during sensory and cognitive tasks in schizophrenia. However, there is emerging, yet contradictory, evidence for increased spontaneous gamma-band activity (i.e., at rest or under baseline conditions). Here, we use the sub-chronic phencyclidine (PCP) rat model for schizophrenia, which has been argued to model the pathophysiology of schizophrenia more closely than acute NMDA antagonism, to investigate gamma oscillations (30-100 Hz) in the medial prefrontal cortex of anesthetized animals. While baseline gamma oscillations were not affected, oscillations induced by train stimulation of the posterior dorsal CA1 (pdCA1) field of the hippocampus were enhanced in PCP-treated animals (5 mg/kg, twice daily for 7 days, followed by a 7-day washout period). This effect was reversed by pharmacological enhancement of endocannabinoid levels via systemic administration of URB597 (0.3 mg/kg), an inhibitor of the catabolic enzyme of the endocannabinoid anandamide. Intriguingly, the pharmacological blockade of CB1 receptors by AM251 unmasked a reduced gamma oscillatory activity in PCP-treated animals. The findings are consistent with the observed effects of URB597 and AM251 on behavioral deficits reminiscent of the symptoms of schizophrenia and further validate the potential for cannabinoid-based drugs as a treatment for schizophrenia.
Collapse
Affiliation(s)
- Alexandre Seillier
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
- Schizophrenia Models for Advancing Research and Treatment, Preclinical Research Program, National Institute of Mental Health, Topolova 748, 250 67, Klecany, Czech Republic.
| |
Collapse
|
2
|
Kasaragod VB, Malinauskas T, Wahid AA, Lengyel J, Knoflach F, Hardwick SW, Jones CF, Chen WN, Lucas X, El Omari K, Chirgadze DY, Aricescu AR, Cecere G, Hernandez MC, Miller PS. The molecular basis of drug selectivity for α5 subunit-containing GABA A receptors. Nat Struct Mol Biol 2023; 30:1936-1946. [PMID: 37903907 PMCID: PMC10716045 DOI: 10.1038/s41594-023-01133-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 09/20/2023] [Indexed: 11/01/2023]
Abstract
α5 subunit-containing γ-aminobutyric acid type A (GABAA) receptors represent a promising drug target for neurological and neuropsychiatric disorders. Altered expression and function contributes to neurodevelopmental disorders such as Dup15q and Angelman syndromes, developmental epilepsy and autism. Effective drug action without side effects is dependent on both α5-subtype selectivity and the strength of the positive or negative allosteric modulation (PAM or NAM). Here we solve structures of drugs bound to the α5 subunit. These define the molecular basis of binding and α5 selectivity of the β-carboline, methyl 6,7-dimethoxy-4-ethyl-β-carboline-3-carboxylate (DMCM), type II benzodiazepine NAMs, and a series of isoxazole NAMs and PAMs. For the isoxazole series, each molecule appears as an 'upper' and 'lower' moiety in the pocket. Structural data and radioligand binding data reveal a positional displacement of the upper moiety containing the isoxazole between the NAMs and PAMs. Using a hybrid molecule we directly measure the functional contribution of the upper moiety to NAM versus PAM activity. Overall, these structures provide a framework by which to understand distinct modulator binding modes and their basis of α5-subtype selectivity, appreciate structure-activity relationships, and empower future structure-based drug design campaigns.
Collapse
Affiliation(s)
- Vikram Babu Kasaragod
- Department of Pharmacology, University of Cambridge, Cambridge, UK
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Tomas Malinauskas
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Ayla A Wahid
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Judith Lengyel
- Roche Pharma Research and Early Development, Neuroscience and Rare Diseases, Roche Innovation Center, Basel, Switzerland
| | - Frederic Knoflach
- Roche Pharma Research and Early Development, Neuroscience and Rare Diseases, Roche Innovation Center, Basel, Switzerland
| | - Steven W Hardwick
- CryoEM Facility, Department of Biochemistry, University of Cambridge, Cambridge, UK
| | | | - Wan-Na Chen
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Xavier Lucas
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center, Basel, Switzerland
| | - Kamel El Omari
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK
| | - Dimitri Y Chirgadze
- CryoEM Facility, Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - A Radu Aricescu
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Giuseppe Cecere
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center, Basel, Switzerland
| | - Maria-Clemencia Hernandez
- Roche Pharma Research and Early Development, Neuroscience and Rare Diseases, Roche Innovation Center, Basel, Switzerland.
| | - Paul S Miller
- Department of Pharmacology, University of Cambridge, Cambridge, UK.
| |
Collapse
|
3
|
The Case for Clinical Trials with Novel GABAergic Drugs in Diabetes Mellitus and Obesity. Life (Basel) 2022; 12:life12020322. [PMID: 35207609 PMCID: PMC8876029 DOI: 10.3390/life12020322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 02/09/2022] [Accepted: 02/16/2022] [Indexed: 11/17/2022] Open
Abstract
Obesity and diabetes mellitus have become the surprising menaces of relative economic well-being worldwide. Gamma amino butyric acid (GABA) has a prominent role in the control of blood glucose, energy homeostasis as well as food intake at several levels of regulation. The effects of GABA in the body are exerted through ionotropic GABAA and metabotropic GABAB receptors. This treatise will focus on the pharmacologic targeting of GABAA receptors to reap beneficial therapeutic effects in diabetes mellitus and obesity. A new crop of drugs selectively targeting GABAA receptors has been under investigation for efficacy in stroke recovery and cognitive deficits associated with schizophrenia. Although these trials have produced mixed outcomes the compounds are safe to use in humans. Preclinical evidence is summarized here to support the rationale of testing some of these compounds in diabetic patients receiving insulin in order to achieve better control of blood glucose levels and to combat the decline of cognitive performance. Potential therapeutic benefits could be achieved (i) By resetting the hypoglycemic counter-regulatory response; (ii) Through trophic actions on pancreatic islets, (iii) By the mobilization of antioxidant defence mechanisms in the brain. Furthermore, preclinical proof-of-concept work, as well as clinical trials that apply the novel GABAA compounds in eating disorders, e.g., olanzapine-induced weight-gain, also appear warranted.
Collapse
|
4
|
Perez SM, McCoy AM, Prevot TD, Mian MY, Carreno FR, Frazer A, Cook JM, Sibille E, Lodge DJ. Hippocampal α5-GABA A Receptors Modulate Dopamine Neuron Activity in the Rat Ventral Tegmental Area. BIOLOGICAL PSYCHIATRY GLOBAL OPEN SCIENCE 2022; 3:78-86. [PMID: 36712569 PMCID: PMC9874136 DOI: 10.1016/j.bpsgos.2021.12.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 11/22/2021] [Accepted: 12/16/2021] [Indexed: 02/01/2023] Open
Abstract
Background Aberrant dopamine neuron activity is attributable to hyperactivity in hippocampal subfields driving a pathological increase in dopamine neuron activity, which is positively correlated with psychosis in humans. Evidence indicates that hippocampal hyperactivity is due to loss of intrinsic GABAergic (gamma-aminobutyric acidergic) inhibition. We have previously demonstrated that hippocampal GABAergic neurotransmission can be modulated by targeting α5-GABAA receptors, which are preferentially expressed in hippocampal regions. Positive and negative allosteric modulators of α5-GABAA receptors (α5-PAMs and α5-NAMs) elicit effects on hippocampal-dependent behaviors. We posited that the selective manipulation of hippocampal inhibition, using α5-PAMs or α5-NAMs, would modulate dopamine activity in control rats. Further, α5-PAMs would reverse aberrant dopamine neuron activity in a rodent model with schizophrenia-related pathophysiologies (methylazoxymethanol acetate [MAM] model). Methods We performed in vivo extracellular recordings of ventral tegmental area dopamine neurons in anesthetized rats to compare the effects of two novel, selective α5-PAMs (GL-II-73, MP-III-022), a nonselective α-PAM (midazolam), and two selective α5-NAMs (L-655,708, TB 21007) in control and MAM-treated male Sprague Dawley rats (n = 5-9). Results Systemic or intracranial administration of selective α5-GABAA receptor modulators regulated dopamine activity. Specifically, both α5-NAMs increased dopamine neuron activity in control rats, whereas GL-II-73, MP-III-022, and L-655,708 attenuated aberrant dopamine neuron activity in MAM-treated rats, an effect mediated by the ventral hippocampus. Conclusions This study demonstrated that α5-GABAA receptor modulation can regulate dopamine neuron activity under control or abnormal activity, providing additional evidence that α5-PAMs and α5-NAMs may have therapeutic applications in psychosis and other psychiatric diseases where aberrant hippocampal activity is present.
Collapse
Affiliation(s)
- Stephanie M. Perez
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, Texas,Audie L. Murphy Memorial Veterans Hospital, South Texas Veterans Health Care System, San Antonio, Texas,Address correspondence to Stephanie M. Perez, Ph.D.
| | - Alexandra M. McCoy
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, Texas,Audie L. Murphy Memorial Veterans Hospital, South Texas Veterans Health Care System, San Antonio, Texas
| | - Thomas D. Prevot
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Md Yeunus Mian
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin
| | - Flavia R. Carreno
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, Texas
| | - Alan Frazer
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, Texas,Audie L. Murphy Memorial Veterans Hospital, South Texas Veterans Health Care System, San Antonio, Texas
| | - James M. Cook
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin
| | - Etienne Sibille
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada,Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Daniel J. Lodge
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, Texas,Audie L. Murphy Memorial Veterans Hospital, South Texas Veterans Health Care System, San Antonio, Texas
| |
Collapse
|
5
|
Modulation of relapse-like drinking in male Sprague-Dawley rats by ligands targeting the α5GABA A receptor. Neuropharmacology 2021; 199:108785. [PMID: 34509495 DOI: 10.1016/j.neuropharm.2021.108785] [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: 04/12/2021] [Revised: 08/26/2021] [Accepted: 09/04/2021] [Indexed: 11/20/2022]
Abstract
Preclinical evidence suggests a key role for GABAA receptors containing the α5 subunit (i.e., α5GABAA receptors) in the abuse-related effects of alcohol, including the reinforcing and discriminative stimulus effects, as well as cue-induced alcohol-seeking behavior. However, the contribution of this GABAA receptor subtype to relapse-like drinking behavior remains unknown. The present study evaluated the capacity of ligands targeting α5GABAA receptors to modulate the alcohol deprivation effect (ADE), a model of relapse-like drinking. Groups of Sprague-Dawley rats underwent repeated cycles of long-term access to alcohol solutions (5%, 10%, 20% v/v) and water in the home cage followed by water only deprivation periods. Upon evidence that the ADE could be reliably expressed across cycles, drug treatment was initiated. One group received the α5GABAA receptor-preferring agonist QH-ii-066 and the other group received the α5GABAA receptor-selective inverse agonist L-655,708. At the end of ADE testing, rats underwent testing in the elevated zero maze under vehicle or L-655,708 treatment for assessment of anxiety-like behavior. The ADE was reliably expressed across repeated cycles of alcohol access/deprivation in a subset of rats. Low doses of QH-ii-066 enhanced expression of the ADE; whereas, L-655,708 dose-dependently inhibited expression of the ADE. L-655,708 did not engender anxiogenic effects in the elevated zero maze under the conditions evaluated. These findings suggest a key role for α5GABAA receptor mechanisms in relapse-like drinking. Moreover, they suggest that α5GABAA receptors may represent a novel pharmacological target for the development of medications to prevent or reduce alcohol relapse.
Collapse
|
6
|
Basmisanil, a highly selective GABA A-α5 negative allosteric modulator: preclinical pharmacology and demonstration of functional target engagement in man. Sci Rep 2021; 11:7700. [PMID: 33833333 PMCID: PMC8032764 DOI: 10.1038/s41598-021-87307-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 03/26/2021] [Indexed: 12/21/2022] Open
Abstract
GABAA-α5 subunit-containing receptors have been shown to play a key modulatory role in cognition and represent a promising drug target for cognitive dysfunction, as well as other disorders. Here we report on the preclinical and early clinical profile of a novel GABAA-α5 selective negative allosteric modulator (NAM), basmisanil, which progressed into Phase II trials for intellectual disability in Down syndrome and cognitive impairment associated with schizophrenia. Preclinical pharmacology studies showed that basmisanil is the most selective GABAA-α5 receptor NAM described so far. Basmisanil bound to recombinant human GABAA-α5 receptors with 5 nM affinity and more than 90-fold selectivity versus α1, α2, and α3 subunit-containing receptors. Moreover, basmisanil inhibited GABA-induced currents at GABAA-α5 yet had little or no effect at the other receptor subtypes. An in vivo occupancy study in rats showed dose-dependent target engagement and was utilized to establish the plasma exposure to receptor occupancy relationship. At estimated receptor occupancies between 30 and 65% basmisanil attenuated diazepam-induced spatial learning impairment in rats (Morris water maze), improved executive function in non-human primates (object retrieval), without showing anxiogenic or proconvulsant effects in rats. During the Phase I open-label studies, basmisanil showed good safety and tolerability in healthy volunteers at maximum GABAA-α5 receptor occupancy as confirmed by PET analysis with the tracer [11C]-Ro 15-4513. An exploratory EEG study provided evidence for functional activity of basmisanil in human brain. Therefore, these preclinical and early clinical studies show that basmisanil has an ideal profile to investigate potential clinical benefits of GABAA-α5 receptor negative modulation.
Collapse
|
7
|
Manzo MA, Wang DS, Li WW, Pinguelo A, Popa MO, Khodaei S, Atack JR, Ross RA, Orser BA. Inhibition of a tonic inhibitory conductance in mouse hippocampal neurones by negative allosteric modulators of α5 subunit-containing γ-aminobutyric acid type A receptors: implications for treating cognitive deficits. Br J Anaesth 2020; 126:674-683. [PMID: 33388140 DOI: 10.1016/j.bja.2020.11.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 10/30/2020] [Accepted: 11/16/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Multiple cognitive and psychiatric disorders are associated with an increased tonic inhibitory conductance that is generated by α5 subunit-containing γ-aminobutyric acid type A (α5 GABAA) receptors. Negative allosteric modulators that inhibit α5 GABAA receptors (α5-NAMs) are being developed as treatments for these disorders. The effects of α5-NAMs have been studied on recombinant GABAA receptors expressed in non-neuronal cells; however, no study has compared drug effects on the tonic conductance generated by native GABAA receptors in neurones, which was the goal of this study. METHODS The effects of five α5-NAMs (basmisanil, Ono-160, L-655,708, α5IA, and MRK-016) on tonic current evoked by a low concentration of GABA were studied using whole-cell recordings in cultured mouse hippocampal neurones. Drug effects on current evoked by a saturating concentration of GABA and on miniature inhibitory postsynaptic currents (mIPSCs) were also examined. RESULTS The α5-NAMs caused a concentration-dependent decrease in tonic current. The potencies varied as the inhibitory concentration for 50% inhibition (IC50) of basmisanil (127 nM) was significantly higher than those of the other compounds (0.4-0.8 nM). In contrast, the maximal efficacies of the drugs were similar (35.5-51.3% inhibition). The α5-NAMs did not modify current evoked by a saturating GABA concentration or mIPSCs. CONCLUSIONS Basmisanil was markedly less potent than the other α5-NAMs, an unexpected result based on studies of recombinant α5 GABAA receptors. Studying the effects of α5 GABAA receptor-selective drugs on the tonic inhibitory current in neurones could inform the selection of compounds for future clinical trials.
Collapse
Affiliation(s)
- Marc A Manzo
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Dian-Shi Wang
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Winston W Li
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Arsène Pinguelo
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Mariana O Popa
- Medicines Discovery Institute, Cardiff University, Cardiff, Wales
| | - Shahin Khodaei
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - John R Atack
- Medicines Discovery Institute, Cardiff University, Cardiff, Wales
| | - Ruth A Ross
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Beverley A Orser
- Department of Physiology, University of Toronto, Toronto, ON, Canada; Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, ON, Canada; Department of Anesthesia, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.
| |
Collapse
|
8
|
Chandler CM, Reeves-Darby J, Jones SA, McDonald JA, Li G, Rahman MT, Cook JM, Platt DM. α5GABA A subunit-containing receptors and sweetened alcohol cue-induced reinstatement and active sweetened alcohol self-administration in male rats. Psychopharmacology (Berl) 2019; 236:1797-1806. [PMID: 30637435 PMCID: PMC6606346 DOI: 10.1007/s00213-018-5163-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 12/28/2018] [Indexed: 12/15/2022]
Abstract
RATIONALE GABAA receptors containing the α5 subunit (i.e., α5GABAA receptors) appear to be critically involved in the reinforcing and subjective effects of alcohol. Their role in alcohol relapse remains unknown. OBJECTIVES Pharmacological approaches were used to probe the role of α5GABAA receptors in alcohol seeking induced by re-exposure to a sweetened alcohol-paired cue, as well as in alcohol + sucrose vs. sucrose self-administration. METHODS For reinstatement studies, rats were trained to self-administer alcohol under a fixed-ratio schedule in which responding was maintained by alcohol + sucrose deliveries and an alcohol-paired stimulus. Sweetened alcohol seeking was extinguished by eliminating solution deliveries and the sweetened alcohol-paired stimulus. During reinstatement tests, animals received pretreatments of an α5GABAA inverse agonist (L-655,708) or an agonist (QH-ii-066) prior to sessions in which presentation of the sweetened alcohol-paired stimulus was restored, but no solution was delivered. For self-administration studies, rats were trained to self-administer alcohol + sucrose or sucrose under a fixed-ratio schedule. Once stable, animals received pretreatments of QH-ii-066, L-655,708, the inverse agonist RY-023, or naltrexone. RESULTS L-655,708 attenuated reinstatement of sweetened alcohol seeking by alcohol + sucrose-paired cues; whereas sweetened alcohol-seeking behavior was augmented by QH-ii-066, albeit at different doses in different rats. Both L-655,708 and RY-023 selectively reduced alcohol + sucrose vs. sucrose self-administration. In contrast, naltrexone reduced both alcohol + sucrose and sucrose self-administration; whereas QH-ii-066 enhanced sucrose self-administration only. CONCLUSIONS α5GABAA receptors play a key role in the modulation of sweetened alcohol cue-induced reinstatement, as well as in alcohol + sucrose but not sucrose self-administration. Inverse agonist activity at α5GABAA receptors may offer a novel strategy for both the reduction of problematic drinking and the prevention of relapse.
Collapse
Affiliation(s)
- Cassie M. Chandler
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS 39216
| | - Jaren Reeves-Darby
- Department of Psychiatry & Human Behavior, University of Mississippi Medical Center, Jackson, MS 39216
| | - Sherman A. Jones
- Department of Psychiatry & Human Behavior, University of Mississippi Medical Center, Jackson, MS 39216
| | - J. Abigail McDonald
- Department of Psychiatry & Human Behavior, University of Mississippi Medical Center, Jackson, MS 39216
| | - Guanguan Li
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI 53211
| | - Md T. Rahman
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI 53211
| | - James M. Cook
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI 53211
| | - Donna M. Platt
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS 39216,Department of Psychiatry & Human Behavior, University of Mississippi Medical Center, Jackson, MS 39216,Correspondence: Donna M. Platt, Ph.D.; Department of Psychiatry & Human Behavior, University of Mississippi Medical Center, 2500 North State St., Jackson, MS 39216, USA; phone: 601-984-5896; fax: 601-984-5899;
| |
Collapse
|
9
|
Short-Term Exposure to Enriched Environment in Adult Rats Restores MK-801-Induced Cognitive Deficits and GABAergic Interneuron Immunoreactivity Loss. Mol Neurobiol 2019; 55:26-41. [PMID: 28822057 DOI: 10.1007/s12035-017-0715-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Perinatal injections of N-methyl-D-aspartate (NMDA) receptor antagonist in rodents emulate some cognitive impairments and neurochemical alterations, such as decreased GABAergic (gamma aminobutyric acid) interneuron immunoreactivity, also found in schizophrenia. These features are pervasive, and developing neuroprotective or neurorestorative strategies is of special interest. In this work, we aimed to investigate if a short exposure to enriched environment (EE) in early adulthood (P55-P73) was an effective strategy to improve cognitive dysfunction and to restore interneuron expression in medial prefrontal cortex (mPFC) and hippocampus (HPC). For that purpose, we administered MK-801 intraperitoneally to Long Evans rats from postnatal days 10 to 20. Twenty-four hours after the last injection, MK-801 produced a transient decrease in spontaneous motor activity and exploration, but those abnormalities were absent at P24 and P55. The open field test on P73 manifested that EE reduced anxiety-like behavior. In addition, MK-801-treated rats showed cognitive impairment in novel object recognition test that was reversed by EE. We quantified different interneuron populations based on their calcium-binding protein expression (parvalbumin, calretinin, and calbindin), glutamic acid decarboxylase 67, and neuronal nuclei-positive cells by means of unbiased stereology and found that EE enhanced interneuron immunoreactivity up to normal values in MK-801-treated rats. Our results demonstrate that a timely intervention with EE is a powerful tool to reverse long-lasting changes in cognition and neurochemical markers of interneurons in an animal model of schizophrenia.
Collapse
|
10
|
Mohamad FH, Has ATC. The α5-Containing GABA A Receptors-a Brief Summary. J Mol Neurosci 2019; 67:343-351. [PMID: 30607899 DOI: 10.1007/s12031-018-1246-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Accepted: 12/17/2018] [Indexed: 12/21/2022]
Abstract
GABAA receptors are the major inhibitory neurotransmitter receptor in the human brain. The receptors are assembled from combination of protein subunits in pentameric complex which may consist of α1-6, β1-3, γ1-3, ρ1-3, δ, ε, θ, or π subunits. There are a theoretical > 150,000 possible assemblies and arrangements of GABAA subunits, although only a few combinations have been found in human with the most dominant consists of 2α1, 2β2, and 1γ2 in a counterclockwise arrangement as seen from the synaptic cleft. The receptors also possess binding sites for various unrelated substances including benzodiazepines, barbiturates, and anesthetics. The α5-containing GABAARs only make up ≤ 5% of the entire receptor population, but up to 25% of the receptor subtype is located in the crucial learning and memory-associated area of the brain-the hippocampus, which has ignited myriads of hypotheses and theories in regard to its role. As well as exhibiting synaptic phasic inhibition, the α5-containing receptors are also extrasynaptic and mediate tonic inhibition with continuously occurring smaller amplitude. Studies on negative-allosteric modulators for reducing this tonic inhibition have been shown to enhance learning and memory in neurological disorders such as schizophrenia, Down syndrome, and autism with a possible alternative benzodiazepine binding site. Therefore, a few α5 subunit-specific compounds have been developed to address these pharmacological needs. With its small population, the α5-containing receptors could be the key and also the answer for many untreated cognitive dysfunctions and disorders.
Collapse
Affiliation(s)
- Fatin H Mohamad
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kampus Kesihatan, 16150, Kubang Kerian, Kelantan, Malaysia
| | - Ahmad Tarmizi Che Has
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kampus Kesihatan, 16150, Kubang Kerian, Kelantan, Malaysia.
| |
Collapse
|
11
|
Golovko AI, Ivanov MB, Golovko ES, Dolgo-Saburov VB, Zatsepin EP. The Neurochemical Mechanisms of the Pharmacological Activities of Inverse Agonists of the Benzodiazepine Binding Site. NEUROCHEM J+ 2018. [DOI: 10.1134/s1819712418030042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
12
|
Cadinu D, Grayson B, Podda G, Harte MK, Doostdar N, Neill JC. NMDA receptor antagonist rodent models for cognition in schizophrenia and identification of novel drug treatments, an update. Neuropharmacology 2018; 142:41-62. [DOI: 10.1016/j.neuropharm.2017.11.045] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 10/28/2017] [Accepted: 11/27/2017] [Indexed: 01/05/2023]
|
13
|
Calvo-Flores Guzmán B, Vinnakota C, Govindpani K, Waldvogel HJ, Faull RL, Kwakowsky A. The GABAergic system as a therapeutic target for Alzheimer's disease. J Neurochem 2018; 146:649-669. [DOI: 10.1111/jnc.14345] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 02/21/2018] [Accepted: 03/14/2018] [Indexed: 12/14/2022]
Affiliation(s)
- Beatriz Calvo-Flores Guzmán
- Centre for Brain Research; Faculty of Medical and Health Sciences; Department of Anatomy and Medical Imaging; University of Auckland; Auckland New Zealand
| | - Chitra Vinnakota
- Centre for Brain Research; Faculty of Medical and Health Sciences; Department of Anatomy and Medical Imaging; University of Auckland; Auckland New Zealand
| | - Karan Govindpani
- Centre for Brain Research; Faculty of Medical and Health Sciences; Department of Anatomy and Medical Imaging; University of Auckland; Auckland New Zealand
| | - Henry J. Waldvogel
- Centre for Brain Research; Faculty of Medical and Health Sciences; Department of Anatomy and Medical Imaging; University of Auckland; Auckland New Zealand
| | - Richard L.M. Faull
- Centre for Brain Research; Faculty of Medical and Health Sciences; Department of Anatomy and Medical Imaging; University of Auckland; Auckland New Zealand
| | - Andrea Kwakowsky
- Centre for Brain Research; Faculty of Medical and Health Sciences; Department of Anatomy and Medical Imaging; University of Auckland; Auckland New Zealand
| |
Collapse
|
14
|
Quercetin Reduces Cortical GABAergic Transmission and Alleviates MK-801-Induced Hyperactivity. EBioMedicine 2018; 34:201-213. [PMID: 30057312 PMCID: PMC6116474 DOI: 10.1016/j.ebiom.2018.07.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 07/11/2018] [Accepted: 07/20/2018] [Indexed: 02/06/2023] Open
Abstract
An imbalance between neuronal excitation and inhibition represents a core feature in multiple neuropsychiatry disorders, necessitating the development of novel strategies to calibrate the excitatory–inhibitory balance of therapeutics. Here we identify a natural compound quercetin that reduces prefrontal cortical GABAergic transmission and alleviates the hyperactivity induced by glutamatergic N-methyl-d-aspartate receptor antagonist MK-801. Quercetin markedly reduced the GABA-activated currents in a noncompetitive manner in cultured cortical neurons, and moderately inhibited spontaneous and electrically-evoked GABAergic inhibitory postsynaptic current in mouse prefrontal cortical slices. Notably, systemic and prefrontal-specific delivery of quercetin reduced basal locomotor activity in addition to alleviated the MK-801-induced hyperactivity. The effects of quercetin were not exclusively dependent on α5-subunit-containing A type GABA receptors (GABAARs), as viral-mediated, region-specific genetic knockdown of the α5-subunit in prefrontal cortex improved the MK-801-evoked psychotic symptom but reserved the pharmacological responsivity to quercetin. Both interventions together completely normalized the locomotor activity. Together, quercetin as a negative allosteric GABAAR modulator exerted antipsychotic activity, facilitating further therapeutic development for the excitatory–inhibitory imbalance disorders.
Collapse
|
15
|
Persistent therapeutic effect of a novel α5-GABA A receptor antagonist in rodent preclinical models of vascular cognitive impairment. Eur J Pharmacol 2018; 834:118-125. [PMID: 30012500 DOI: 10.1016/j.ejphar.2018.07.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 07/10/2018] [Accepted: 07/12/2018] [Indexed: 01/28/2023]
Abstract
This study examined the potential of the selective extra-synaptic α5-GABAA receptor inhibitor S44819 (Egis-13529) to improve cognitive performance in preclinical models of vascular cognitive impairment (VCI). Chronic hypoperfusion of the brain in mice was induced by permanent occlusion of the right common carotid artery (rUCO). rUCO induced impairments of cognitive function in the object recognition test (OR) and the rewarded T-maze (RTM). In both tests, a single oral treatment with S44819 (OR - 0.1-3 mg/kg, RTM - 1-3 mg/kg p.o.) significantly reduced the effect of rUCO. Long-term treatment with S44819 (1-10 mg/kg twice daily p.o. for 14 days), that was initiated 24 h after surgery and was followed by a 10- or 13-day wash-out period, fully prevented the decline of cognitive performance of rUCO mice. In rats, occlusion of the middle cerebral artery (MCA) for 30 min caused a significantly diminished performance in the OR. This was prevented by S44819 given p.o. 15 mg/kg twice daily for 8 days, starting 7 days after surgery and tested following a 7-day wash-out period. Taken together, S44819 markedly and stably improved reference and working memory impaired by rUCO in mice. In rats, the compound effectively suppressed the development of cognitive impairment after mild stroke. In conclusion, as longer-term administration led to a persistent reversal of the cognitive deficits, it appears that S44819 may have symptomatic, as well as disease-modifying effects in models of VCI. Proof of concept is therefore provided for testing S44819 in the therapy of VCI and post-stroke dementia in humans.
Collapse
|
16
|
Rajagopal L, Soni D, Meltzer HY. Neurosteroid pregnenolone sulfate, alone, and as augmentation of lurasidone or tandospirone, rescues phencyclidine-induced deficits in cognitive function and social interaction. Behav Brain Res 2018; 350:31-43. [PMID: 29763637 DOI: 10.1016/j.bbr.2018.05.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 04/19/2018] [Accepted: 05/07/2018] [Indexed: 01/01/2023]
Abstract
BACKGROUND Pregnenolone sulfate (PregS), an endogenous neurosteroid, which negatively and positively modulates gamma amino butyric acid subunit A (GABAA) and N-methyl D-aspartate (NMDA) receptors (R) respectively, among other potential neuroplastic changes on synaptic processes, has shown some beneficial effects on treating cognitive impairment associated with schizophrenia (CIAS) and negative symptoms. Lurasidone (Lur), an atypical antipsychotic drug (AAPD), and tandospirone (Tan), a 5-HT1A R partial agonist, have also been reported to improve cognitive or negative symptoms, or both, in some schizophrenia patients. METHODS We tested whether PregS, by itself, and in combination with Lur or Tan could rescue persistent deficits produced by subchronic treatment with the NMDAR antagonist, phencyclidine (PCP)-in episodic memory, executive functioning, and social behavior, using novel object recognition (NOR), operant reversal learning (ORL), and social interaction (SI) tasks, in male C57BL/6 J mice. RESULTS PregS (10, but not 3 mg/kg) significantly rescued subchronic PCP-induced NOR and SI deficits. Co-administration of sub-effective doses (SEDs) of PregS (3 mg/kg) + Lur (0.1 mg/kg) or Tan (0.03 mg/kg) rescued scPCP-induced NOR and SI deficits. Further, PregS (30, but not 10 mg/kg) rescued PCP-induced ORL deficit, as did the combination of SED PregS (10 mg/kg) +SED Lur (1 mg/kg) or Tan (1 mg/kg). CONCLUSION PregS was effective alone and as adjunctive treatment for treating two types of cognitive impairments and negative symptoms in this schizophrenia model. Further study of the mechanisms by which PregS alone and in combination with AAPDs and 5-HT1A R partial agonists, rescues the deficits in cognition and SI in this preclinical model is indicated.
Collapse
Affiliation(s)
- L Rajagopal
- Department of Psychiatry and Behavioral Sciences, Northwestern Feinberg School of Medicine, Chicago IL 60611, USA
| | - D Soni
- Department of Psychiatry and Behavioral Sciences, Northwestern Feinberg School of Medicine, Chicago IL 60611, USA
| | - H Y Meltzer
- Department of Psychiatry and Behavioral Sciences, Northwestern Feinberg School of Medicine, Chicago IL 60611, USA.
| |
Collapse
|
17
|
Xu MY, Wong AHC. GABAergic inhibitory neurons as therapeutic targets for cognitive impairment in schizophrenia. Acta Pharmacol Sin 2018; 39:733-753. [PMID: 29565038 DOI: 10.1038/aps.2017.172] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 12/25/2017] [Indexed: 12/24/2022] Open
Abstract
Schizophrenia is considered primarily as a cognitive disorder. However, functional outcomes in schizophrenia are limited by the lack of effective pharmacological and psychosocial interventions for cognitive impairment. GABA (gamma-aminobutyric acid) interneurons are the main inhibitory neurons in the central nervous system (CNS), and they play a critical role in a variety of pathophysiological processes including modulation of cortical and hippocampal neural circuitry and activity, cognitive function-related neural oscillations (eg, gamma oscillations) and information integration and processing. Dysfunctional GABA interneuron activity can disrupt the excitatory/inhibitory (E/I) balance in the cortex, which could represent a core pathophysiological mechanism underlying cognitive dysfunction in schizophrenia. Recent research suggests that selective modulation of the GABAergic system is a promising intervention for the treatment of schizophrenia-associated cognitive defects. In this review, we summarized evidence from postmortem and animal studies for abnormal GABAergic neurotransmission in schizophrenia, and how altered GABA interneurons could disrupt neuronal oscillations. Next, we systemically reviewed a variety of up-to-date subtype-selective agonists, antagonists, positive and negative allosteric modulators (including dual allosteric modulators) for α5/α3/α2 GABAA and GABAB receptors, and summarized their pro-cognitive effects in animal behavioral tests and clinical trials. Finally, we also discuss various representative histone deacetylases (HDAC) inhibitors that target GABA system through epigenetic modulations, GABA prodrug and presynaptic GABA transporter inhibitors. This review provides important information on current potential GABA-associated therapies and future insights for development of more effective treatments.
Collapse
|
18
|
Pehrson AL, Pedersen CS, Tølbøl KS, Sanchez C. Vortioxetine Treatment Reverses Subchronic PCP Treatment-Induced Cognitive Impairments: A Potential Role for Serotonin Receptor-Mediated Regulation of GABA Neurotransmission. Front Pharmacol 2018; 9:162. [PMID: 29559911 PMCID: PMC5845537 DOI: 10.3389/fphar.2018.00162] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 02/14/2018] [Indexed: 01/21/2023] Open
Abstract
Major depressive disorder (MDD) is associated with cognitive impairments that may contribute to poor functional outcomes. Clinical data suggests that the multimodal antidepressant vortioxetine attenuates some cognitive impairments in MDD patients, but the mechanistic basis for these improvements is unclear. One theory suggests that vortioxetine improves cognition by suppressing γ-amino butyric acid (GABA)ergic neurotransmission, thereby increasing glutamatergic activation. Vortioxetine’s effects on cognition, GABA and glutamate neurotransmission have been supported in separate experiments, but no empirical work has directly connected vortioxetine’s cognitive effects to those on GABA and glutamate neurotransmission. In this paper, we attempt to bridge this gap by evaluating vortioxetine’s effects in the subchronic PCP (subPCP) model, which induces impaired cognitive function and altered GABA and glutamate neurotransmission. We demonstrate that acute or subchronic vortioxetine treatment attenuated subPCP-induced deficits in attentional set shifting (AST) performance, and that the selective 5-HT3 receptor antagonist ondansetron or the 5-HT reuptake inhibitor escitalopram could mimic this effect. Furthermore, acute vortioxetine treatment reversed subPCP-induced object recognition (OR) deficits in rats, while subchronic vortioxetine reversed subPCP-induced Object Recognition and object placement impairments in mice. Finally, subPCP treatment reduced GABAB receptor expression in a manner that was insensitive to vortioxetine treatment, and subchronic vortioxetine treatment alone, but not in combination with subPCP, significantly increased GABA’s affinity for the GABAA receptor. These data suggest that vortioxetine reverses cognitive impairments in a model associated with altered GABA and glutamate neurotransmission, further supporting the hypothesis that vortioxetine’s GABAergic and glutamatergic effects are relevant for cognitive function.
Collapse
Affiliation(s)
- Alan L Pehrson
- Department of Psychology, Montclair State University, Montclair, NJ, United States
| | | | | | - Connie Sanchez
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| |
Collapse
|
19
|
Tait DS, Bowman EM, Neuwirth LS, Brown VJ. Assessment of intradimensional/extradimensional attentional set-shifting in rats. Neurosci Biobehav Rev 2018; 89:72-84. [PMID: 29474818 DOI: 10.1016/j.neubiorev.2018.02.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 02/06/2018] [Accepted: 02/19/2018] [Indexed: 01/07/2023]
Abstract
The rat intradimensional/extradimensional (ID/ED) task, first described by Birrell and Brown 18 years ago, has become the predominant means by which attentional set-shifting is investigated in rodents: the use of rats in the task has been described in over 135 publications by researchers from nearly 90 universities and pharmaceutical companies. There is variation in the protocols used by different groups, including differences in apparatus, stimuli (both stimulus dimensions and exemplars within), and also the methodology. Nevertheless, most of these variations seem to be of little consequence: there is remarkable similarity in the profile of published data, with consistency of learning rates and in the size and reliability of the set-shifting and reversal 'costs'. However, we suspect that there may be inconsistent data that is unpublished or perhaps 'failed experiments' that may have been caused by unintended deviations from effective protocols. The purpose of this review is to describe our approach and the rationale behind certain aspects of the protocol, including common pitfalls that are encountered when establishing an effective local protocol.
Collapse
Affiliation(s)
- David S Tait
- School of Psychology and Neuroscience, University of St Andrews, St Mary's Quad, South Street, St Andrews, Fife, KY16 9JP, UK.
| | - Eric M Bowman
- School of Psychology and Neuroscience, University of St Andrews, St Mary's Quad, South Street, St Andrews, Fife, KY16 9JP, UK
| | - Lorenz S Neuwirth
- Department of Psychology, SUNY Old Westbury, Old Westbury, NY, 11568, USA; SUNY Neuroscience Research Institute, Old Westbury, NY, 11568, USA
| | - Verity J Brown
- School of Psychology and Neuroscience, University of St Andrews, St Mary's Quad, South Street, St Andrews, Fife, KY16 9JP, UK
| |
Collapse
|
20
|
Pálvölgyi A, Móricz K, Pataki Á, Mihalik B, Gigler G, Megyeri K, Udvari S, Gacsályi I, Antoni FA. Loop F of the GABA A receptor alpha subunit governs GABA potency. Neuropharmacology 2018; 128:408-415. [DOI: 10.1016/j.neuropharm.2017.10.042] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 10/29/2017] [Accepted: 10/31/2017] [Indexed: 12/28/2022]
|
21
|
Hippocampal GABA A antagonism reverses the novel object recognition deficit in sub-chronic phencyclidine-treated rats. Behav Brain Res 2017; 342:11-18. [PMID: 29289597 DOI: 10.1016/j.bbr.2017.12.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 12/20/2017] [Accepted: 12/26/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND Abnormalities in prefrontal cortical and hippocampal GABAergic function are postulated to be major causes of the cognitive impairment associated with schizophrenia (CIAS). There are conflicting views on whether diminished or enhanced GABAergic activity contributes to the deficit in short-term novel object recognition (NOR) in the sub-chronic phencyclidine (scPCP) rodent model of CIAS. This study assessed the role of GABAA signaling in the medial prefrontal cortex (mPFC) and ventral hippocampus (vHPC) in NOR in saline (scSAL)- and scPCP-treated rats. METHODS The effects of local administration of a GABAA agonist (muscimol) into the vHPC or mPFC and an antagonist (bicuculline) or a GABAA/benzodiazepine partial agonist (bretazenil) into the vHPC on NOR in scSAL and scPCP-treated rats were determined. RESULTS In scSAL-treated rats, injection of muscimol into the vHPC, but not mPFC, induced a deficit in NOR. The scPCP-induced NOR deficit was significantly reversed by intra-vHPC bicuculline, while intra-vHPC bretazenil produced a non-significant trend for reversal (p = .06). scPCP treatment increased mRNA expression of GABAA γ2 in PFC and GABAA α5 and GABAA β1 in the HPC. However, GABA concentration in the PFC or HPC was not altered. CONCLUSIONS These findings indicate that the scPCP-induced NOR deficit can be rescued by reducing GABAA receptor stimulation in vHPC, indicating that increased vHPC GABAA inhibition may contribute to the scPCP-induced NOR deficit in rats. These results also indicate that excessive GABAA receptor signalling in the vHPC has a deleterious effect on NOR in normal rats.
Collapse
|
22
|
GABA A receptor subunit deregulation in the hippocampus of human foetuses with Down syndrome. Brain Struct Funct 2017; 223:1501-1518. [PMID: 29168008 PMCID: PMC5869939 DOI: 10.1007/s00429-017-1563-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 11/05/2017] [Indexed: 11/01/2022]
Abstract
The function, regulation and cellular distribution of GABAA receptor subunits have been extensively documented in the adult rodent brain and are linked to numerous neurological disorders. However, there is a surprising lack of knowledge on the cellular (sub-) distribution of GABAA receptor subunits and of their expressional regulation in developing healthy and diseased foetal human brains. To propose a role for GABAA receptor subunits in neurodevelopmental disorders, we studied the developing hippocampus of normal and Down syndrome foetuses. Among the α1-3 and γ2 subunits probed, we find significantly altered expression profiles of the α1, α3 and γ2 subunits in developing Down syndrome hippocampi, with the α3 subunit being most affected. α3 subunits were selectively down-regulated in all hippocampal subfields and developmental periods tested in Down syndrome foetuses, presenting a developmental mismatch by their adult-like distribution in early foetal development. We hypothesized that increased levels of the amyloid precursor protein (APP), and particularly its neurotoxic β-amyloid (1-42) fragment, could disrupt α3 gene expression, likely by facilitating premature neuronal differentiation. Indeed, we find increased APP content in the hippocampi of the Down foetuses. In a corresponding cellular model, soluble β-amyloid (1-42) administered to cultured SH-SY5Y neuroblastoma cells, augmented by retinoic acid-induced differentiation towards a neuronal phenotype, displayed a reduction in α3 subunit levels. In sum, this study charts a comprehensive regional and subcellular map of key GABAA receptor subunits in identified neuronal populations in the hippocampus of healthy and Down syndrome foetuses and associates increased β-amyloid load with discordant down-regulation of α3 subunits.
Collapse
|
23
|
Mar AC, Nilsson SRO, Gamallo-Lana B, Lei M, Dourado T, Alsiö J, Saksida LM, Bussey TJ, Robbins TW. MAM-E17 rat model impairments on a novel continuous performance task: effects of potential cognitive enhancing drugs. Psychopharmacology (Berl) 2017; 234:2837-2857. [PMID: 28744563 PMCID: PMC5591806 DOI: 10.1007/s00213-017-4679-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 06/18/2017] [Indexed: 12/02/2022]
Abstract
RATIONALE Impairments in attention and inhibitory control are endophenotypic markers of neuropsychiatric disorders such as schizophrenia and represent key targets for therapeutic management. Robust preclinical models and assays sensitive to clinically relevant treatments are crucial for improving cognitive enhancement strategies. OBJECTIVES We assessed a rodent model with neural and behavioral features relevant to schizophrenia (gestational day 17 methylazoxymethanol acetate treatment (MAM-E17)) on a novel test of attention and executive function, and examined the impact of putative nootropic drugs. METHODS MAM-E17 and sham control rats were trained on a novel touchscreen-based rodent continuous performance test (rCPT) designed to closely mimic the human CPT paradigm. Performance following acute, systemic treatment with an array of pharmacological compounds was investigated. RESULTS Two cohorts of MAM-E17 rats were impaired on rCPT performance including deficits in sensitivity (d') and increased false alarm rates (FARs). Sulpiride (0-30 mg/kg) dose-dependently reduced elevated FAR in MAM-E17 rats whereas low-dose modafinil (8 mg/kg) only improved d' in sham controls. ABT-594 (5.9-19.4 μg/kg) and modafinil (64 mg/kg) showed expected stimulant-like effects, while LSN2463359 (5 mg/kg), RO493858 (10 mg/kg), atomoxetine (0.3-1 mg/kg), and sulpiride (30 mg/kg) showed expected suppressant effects on performance across all animals. Donepezil (0.1-1 mg/kg) showed near-significant enhancements in d', and EVP-6124 (0.3-3 mg/kg) exerted no effects in the rCPT paradigm. CONCLUSION The MAM-E17 model exhibits robust and replicable impairments in rCPT performance that resemble attention and inhibitory control deficits seen in schizophrenia. Pharmacological profiles were highly consistent with known drug effects on cognition in preclinical and clinical studies. The rCPT is a sensitive and reliable tool with high translational potential for understanding the etiology and treatment of disorders affecting attention and executive dysfunction.
Collapse
Affiliation(s)
- Adam C Mar
- Neuroscience Institute, New York University Medical Center, New York, NY, 10016, USA.
- Department of Neuroscience and Physiology, New York University Medical Center, New York, NY, USA.
- Department of Psychology, University of Cambridge, Cambridge, UK.
- MRC and Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK.
| | - Simon R O Nilsson
- Neuroscience Institute, New York University Medical Center, New York, NY, 10016, USA
- Department of Neuroscience and Physiology, New York University Medical Center, New York, NY, USA
- Department of Psychology, University of Cambridge, Cambridge, UK
- MRC and Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
| | - Begoña Gamallo-Lana
- Neuroscience Institute, New York University Medical Center, New York, NY, 10016, USA
- Department of Neuroscience and Physiology, New York University Medical Center, New York, NY, USA
- Department of Psychology, University of Cambridge, Cambridge, UK
- MRC and Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
| | - Ming Lei
- Department of Psychology, University of Cambridge, Cambridge, UK
- MRC and Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Department of Health Industry Management, Beijing International Studies University, 1 Dingfuzhuang Nanli, Beijing, China
| | - Theda Dourado
- Department of Psychology, University of Cambridge, Cambridge, UK
- MRC and Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
| | - Johan Alsiö
- Department of Psychology, University of Cambridge, Cambridge, UK
- MRC and Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Department of Neuroscience, Unit of Functional Neurobiology, University of Uppsala, Uppsala, Sweden
| | - Lisa M Saksida
- Department of Psychology, University of Cambridge, Cambridge, UK
- MRC and Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Molecular Medicine Research Group, Robarts Research Institute, Western University, London, ON, Canada
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
- The Brain and Mind Institute, Western University, London, ON, Canada
| | - Timothy J Bussey
- Department of Psychology, University of Cambridge, Cambridge, UK
- MRC and Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Molecular Medicine Research Group, Robarts Research Institute, Western University, London, ON, Canada
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
- The Brain and Mind Institute, Western University, London, ON, Canada
| | - Trevor W Robbins
- Department of Psychology, University of Cambridge, Cambridge, UK
- MRC and Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
| |
Collapse
|
24
|
Behavioural pharmacology of the α5-GABA A receptor antagonist S44819: Enhancement and remediation of cognitive performance in preclinical models. Neuropharmacology 2017; 125:30-38. [DOI: 10.1016/j.neuropharm.2017.07.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 07/04/2017] [Accepted: 07/06/2017] [Indexed: 11/24/2022]
|
25
|
Etherington LA, Mihalik B, Pálvölgyi A, Ling I, Pallagi K, Kertész S, Varga P, Gunn BG, Brown AR, Livesey MR, Monteiro O, Belelli D, Barkóczy J, Spedding M, Gacsályi I, Antoni FA, Lambert JJ. Selective inhibition of extra-synaptic α5-GABA A receptors by S44819, a new therapeutic agent. Neuropharmacology 2017; 125:353-364. [PMID: 28807671 DOI: 10.1016/j.neuropharm.2017.08.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/07/2017] [Accepted: 08/09/2017] [Indexed: 01/18/2023]
Abstract
In the mammalian central nervous system (CNS) GABAA receptors (GABAARs) mediate neuronal inhibition and are important therapeutic targets. GABAARs are composed of 5 subunits, drawn from 19 proteins, underpinning expression of 20-30 GABAAR subtypes. In the CNS these isoforms are heterogeneously expressed and exhibit distinct physiological and pharmacological properties. We report the discovery of S44819, a novel tricyclic oxazolo-2,3-benzodiazepine-derivative, that selectively inhibits α5-subunit-containing GABAARs (α5-GABAARs). Current α5-GABAAR inhibitors bind to the "benzodiazepine site". However, in HEK293 cells expressing recombinant α5-GABAARs, S44819 had no effect on 3H-flumazenil binding, but displaced the GABAAR agonist 3H-muscimol and competitively inhibited the GABA-induced responses. Importantly, we reveal that the α5-subunit selectivity is uniquely governed by amino acid residues within the α-subunit F-loop, a region associated with GABA binding. In mouse hippocampal CA1 neurons, S44819 enhanced long-term potentiation (LTP), blocked a tonic current mediated by extrasynaptic α5-GABAARs, but had no effect on synaptic GABAARs. In mouse thalamic neurons, S44819 had no effect on the tonic current mediated by δ-GABAARs, or on synaptic (α1β2γ2) GABAARs. In rats, S44819 enhanced object recognition memory and reversed scopolamine-induced impairment of working memory in the eight-arm radial maze. In conclusion, S44819 is a first in class compound that uniquely acts as a potent, competitive, selective antagonist of recombinant and native α5-GABAARs. Consequently, S44819 enhances hippocampal synaptic plasticity and exhibits pro-cognitive efficacy. Given this profile, S44819 may improve cognitive function in neurodegenerative disorders and facilitate post-stroke recovery.
Collapse
Affiliation(s)
- Lori-An Etherington
- Division of Neuroscience, Medical Research Institute, Ninewells Hospital & Medical School, Dundee University, Dundee, DD19SY, Scotland, UK
| | - Balázs Mihalik
- Biotalentum Kft, Gödöllő, Aulich Lajos u. 26, 2100, Hungary
| | | | - István Ling
- Egis Pharmaceuticals PLC, H1106, Budapest, Pf.100, Hungary
| | | | | | - Péter Varga
- Egis Pharmaceuticals PLC, H1106, Budapest, Pf.100, Hungary
| | - Ben G Gunn
- Division of Neuroscience, Medical Research Institute, Ninewells Hospital & Medical School, Dundee University, Dundee, DD19SY, Scotland, UK
| | - Adam R Brown
- Division of Neuroscience, Medical Research Institute, Ninewells Hospital & Medical School, Dundee University, Dundee, DD19SY, Scotland, UK
| | - Matthew R Livesey
- Division of Neuroscience, Medical Research Institute, Ninewells Hospital & Medical School, Dundee University, Dundee, DD19SY, Scotland, UK
| | - Olivia Monteiro
- Division of Neuroscience, Medical Research Institute, Ninewells Hospital & Medical School, Dundee University, Dundee, DD19SY, Scotland, UK
| | - Delia Belelli
- Division of Neuroscience, Medical Research Institute, Ninewells Hospital & Medical School, Dundee University, Dundee, DD19SY, Scotland, UK
| | | | - Michael Spedding
- Institut de Recherches Servier, Croissy-sur-Seine, 78290, France
| | | | | | - Jeremy J Lambert
- Division of Neuroscience, Medical Research Institute, Ninewells Hospital & Medical School, Dundee University, Dundee, DD19SY, Scotland, UK.
| |
Collapse
|
26
|
McLean SL, Harte MK, Neill JC, Young AM. Dopamine dysregulation in the prefrontal cortex relates to cognitive deficits in the sub-chronic PCP-model for schizophrenia: A preliminary investigation. J Psychopharmacol 2017; 31:660-666. [PMID: 28441905 DOI: 10.1177/0269881117704988] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Dopamine dysregulation in the prefrontal cortex (PFC) plays an important role in cognitive dysfunction in schizophrenia. Sub-chronic phencyclidine (scPCP) treatment produces cognitive impairments in rodents and is a thoroughly validated animal model for cognitive deficits in schizophrenia. The aim of our study was to investigate the role of PFC dopamine in scPCP-induced deficits in a cognitive task of relevance to the disorder, novel object recognition (NOR). METHODS Twelve adult female Lister Hooded rats received scPCP (2 mg/kg) or vehicle via the intraperitoneal route twice daily for 7 days, followed by 7 days washout. In vivo microdialysis was carried out prior to, during and following the NOR task. RESULTS Vehicle rats successfully discriminated between novel and familiar objects and this was accompanied by a significant increase in dopamine in the PFC during the retention trial ( p < 0.01). scPCP produced a significant deficit in NOR ( p < 0.05 vs. control) and no PFC dopamine increase was observed. CONCLUSIONS These data demonstrate an increase in dopamine during the retention trial in vehicle rats that was not observed in scPCP-treated rats accompanied by cognitive disruption in the scPCP group. This novel finding suggests a mechanism by which cognitive deficits are produced in this animal model and support its use for investigating disorders in which PFC dopamine is central to the pathophysiology.
Collapse
Affiliation(s)
- Samantha L McLean
- 1 School of Pharmacy and Medical Sciences, University of Bradford, Bradford, UK
| | - Michael K Harte
- 2 Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester, UK
| | - Joanna C Neill
- 2 Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester, UK
| | - Andrew Mj Young
- 3 Department of Neuroscience, Psychology and Behaviour, University of Leicester, Leicester, UK
| |
Collapse
|
27
|
Mihalik B, Pálvölgyi A, Bogár F, Megyeri K, Ling I, Barkóczy J, Bartha F, Martinek TA, Gacsályi I, Antoni FA. Loop-F of the α-subunit determines the pharmacologic profile of novel competitive inhibitors of GABA A receptors. Eur J Pharmacol 2017; 798:129-136. [DOI: 10.1016/j.ejphar.2017.01.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 01/25/2017] [Accepted: 01/25/2017] [Indexed: 12/11/2022]
|
28
|
Stamenić TT, Poe MM, Rehman S, Santrač A, Divović B, Scholze P, Ernst M, Cook JM, Savić MM. Ester to amide substitution improves selectivity, efficacy and kinetic behavior of a benzodiazepine positive modulator of GABA A receptors containing the α5 subunit. Eur J Pharmacol 2016; 791:433-443. [PMID: 27639297 DOI: 10.1016/j.ejphar.2016.09.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 09/07/2016] [Accepted: 09/07/2016] [Indexed: 12/22/2022]
Abstract
We have synthesized and characterized MP-III-022 ((R)-8-ethynyl-6-(2-fluorophenyl)-N,4-dimethyl-4H-benzo[f]imidazo[1,5-a][1,4]diazepine-3-carboxamide) in vitro and in vivo as a binding- and efficacy-selective positive allosteric modulator of GABAA receptors containing the α5 subunit (α5GABAARs). By approximation of the electrophysiological responses which the estimated free rat brain concentrations can induce, we demonstrated that convenient systemic administration of MP-III-022 in the dose range 1-10mg/kg may result in a selective potentiation, over a wide range from mild to moderate to strong, of α5βγ2 GABAA receptors. For eliciting a comparable range of potentiation, the widely studied parent ligand SH-053-2'F-R-CH3 containing an ester moiety needs to be administered over a much wider dose range (10-200mg/kg), but at the price of activating non-α5 GABAARs as well as the desired α5GABAARs at the highest dose. At the dose of 10mg/kg, which elicits a strong positive modulation of α5GABAARs, MP-III-022 caused mild, but significant muscle relaxation, while at doses 1-10mg/kg was devoid of ataxia, sedation or an influence on the anxiety level, characteristic for non-selective benzodiazepines. As an amide compound with improved stability and kinetic properties, MP-III-022 may represent an optimized tool to study the influence of α5GABAARs on the neuronal pathways related to CNS disorders such as schizophrenia, Alzheimer's disease, Down syndrome or autism.
Collapse
Affiliation(s)
- Tamara Timić Stamenić
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia
| | - Michael M Poe
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201, USA
| | - Sabah Rehman
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Anja Santrač
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia
| | - Branka Divović
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia
| | - Petra Scholze
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Margot Ernst
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - James M Cook
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201, USA
| | - Miroslav M Savić
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia.
| |
Collapse
|
29
|
The Novel, Nicotinic Alpha7 Receptor Partial Agonist, BMS-933043, Improves Cognition and Sensory Processing in Preclinical Models of Schizophrenia. PLoS One 2016; 11:e0159996. [PMID: 27467081 PMCID: PMC4965148 DOI: 10.1371/journal.pone.0159996] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 07/12/2016] [Indexed: 01/01/2023] Open
Abstract
The development of alpha7 nicotinic acetylcholine receptor agonists is considered a promising approach for the treatment of cognitive symptoms in schizophrenia patients. In the present studies we characterized the novel agent, (2R)-N-(6-(1H-imidazol-1-yl)-4-pyrimidinyl)-4'H-spiro[4-azabicyclo[2.2.2]octane-2,5'-[1,3]oxazol]-2'-amine (BMS-933043), in vitro and in rodent models of schizophrenia-like deficits in cognition and sensory processing. BMS-933043 showed potent binding affinity to native rat (Ki = 3.3 nM) and recombinant human alpha7 nicotinic acetylcholine receptors (Ki = 8.1 nM) and agonist activity in a calcium fluorescence assay (EC50 = 23.4 nM) and whole cell voltage clamp electrophysiology (EC50 = 0.14 micromolar (rat) and 0.29 micromolar (human)). BMS-933043 exhibited a partial agonist profile relative to acetylcholine; the relative efficacy for net charge crossing the cell membrane was 67% and 78% at rat and human alpha7 nicotinic acetylcholine receptors respectively. BMS-933043 showed no agonist or antagonist activity at other nicotinic acetylcholine receptor subtypes and was at least 300 fold weaker at binding to and antagonizing human 5-HT3A receptors (Ki = 2,451 nM; IC50 = 8,066 nM). BMS-933043 treatment i) improved 24 hour novel object recognition memory in mice (0.1-10 mg/kg, sc), ii) reversed MK-801-induced deficits in Y maze performance in mice (1-10 mg/kg, sc) and set shift performance in rats (1-10 mg/kg, po) and iii) reduced the number of trials required to complete the extradimensional shift discrimination in neonatal PCP treated rats performing the intra-dimensional/extradimensional set shifting task (0.1-3 mg/kg, po). BMS-933043 also improved auditory gating (0.56-3 mg/kg, sc) and mismatch negativity (0.03-3 mg/kg, sc) in rats treated with S(+)ketamine or neonatal phencyclidine respectively. Given this favorable preclinical profile BMS-933043 was selected for further development to support clinical evaluation in humans.
Collapse
|
30
|
Lo FS, Blue ME, Erzurumlu RS. Enhancement of postsynaptic GABAA and extrasynaptic NMDA receptor-mediated responses in the barrel cortex of Mecp2-null mice. J Neurophysiol 2016; 115:1298-306. [PMID: 26683074 PMCID: PMC4808090 DOI: 10.1152/jn.00944.2015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 12/15/2015] [Indexed: 12/12/2022] Open
Abstract
Rett syndrome (RTT) is a neurodevelopmental disorder that results from mutations in the X-linked gene for methyl-CpG-binding protein 2 (MECP2). The underlying cellular mechanism for the sensory deficits in patients with RTT is largely unknown. This study used the Bird mouse model of RTT to investigate sensory thalamocortical synaptic transmission in the barrel cortex of Mecp2-null mice. Electrophysiological results showed an excitation/inhibition imbalance, biased toward inhibition, due to an increase in efficacy of postsynaptic GABAA receptors rather than alterations in inhibitory network and presynaptic release properties. Enhanced inhibition impaired the transmission of tonic sensory signals from the thalamus to the somatosensory cortex. Previous morphological studies showed an upregulation of NMDA receptors in the neocortex of both RTT patients and Mecp2-null mice at early ages [Blue ME, Naidu S, Johnston MV. Ann Neurol 45: 541-545, 1999; Blue ME, Kaufmann WE, Bressler J, Eyring C, O'Driscoll C, Naidu S, Johnston MV. Anat Rec (Hoboken) 294: 1624-1634, 2011]. Although AMPA and NMDA receptor-mediated excitatory synaptic transmission was not altered in the barrel cortex of Mecp2-null mice, extrasynaptic NMDA receptor-mediated responses increased markedly. These responses were blocked by memantine, suggesting that extrasynaptic NMDA receptors play an important role in the pathogenesis of RTT. The results suggest that enhancement of postsynaptic GABAA and extrasynaptic NMDA receptor-mediated responses may underlie impaired somatosensation and that pharmacological blockade of extrasynaptic NMDA receptors may have therapeutic value for RTT.
Collapse
Affiliation(s)
- Fu-Sun Lo
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland; and
| | - Mary E Blue
- Hugo W. Moser Research Institute at Kennedy Krieger, Inc. and Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Reha S Erzurumlu
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland; and
| |
Collapse
|
31
|
Grayson B, Barnes SA, Markou A, Piercy C, Podda G, Neill JC. Postnatal Phencyclidine (PCP) as a Neurodevelopmental Animal Model of Schizophrenia Pathophysiology and Symptomatology: A Review. Curr Top Behav Neurosci 2016; 29:403-428. [PMID: 26510740 DOI: 10.1007/7854_2015_403] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Cognitive dysfunction and negative symptoms of schizophrenia remain an unmet clinical need. Therefore, it is essential that new treatments and approaches are developed to recover the cognitive and social impairments that are seen in patients with schizophrenia. These may only be discovered through the use of carefully validated, aetiologically relevant and translational animal models. With recent renewed interest in the neurodevelopmental hypothesis of schizophrenia, postnatal administration of N-methyl-D-aspartate receptor (NMDAR) antagonists such as phencyclidine (PCP) has been proposed as a model that can mimic aspects of schizophrenia pathophysiology. The purpose of the current review is to examine the validity of this model and compare it with the adult subchronic PCP model. We review the ability of postnatal PCP administration to produce behaviours (specifically cognitive deficits) and neuropathology of relevance to schizophrenia and their subsequent reversal by pharmacological treatments. We review studies investigating effects of postnatal PCP on cognitive domains in schizophrenia in rats. Morris water maze and delayed spontaneous alternation tasks have been used for working memory, attentional set-shifting for executive function, social novelty discrimination for selective attention and prepulse inhibition of acoustic startle for sensorimotor gating. In addition, we review studies on locomotor activity and neuropathology. We also include two studies using dual hit models incorporating postnatal PCP and two studies on social behaviour deficits following postnatal PCP. Overall, the evidence we provide supports the use of postnatal PCP to model cognitive and neuropathological disturbances of relevance to schizophrenia. To date, there is a lack of evidence to support a significant advantage of postnatal PCP over the adult subchronic PCP model and full advantage has not been taken of its neurodevelopmental component. When thoroughly characterised, it is likely that it will provide a useful neurodevelopmental model to complement other models such as maternal immune activation, particularly when combined with other manipulations to produce dual or triple hit models. However, the developmental trajectory of behavioural and neuropathological changes induced by postnatal PCP and their relevance to schizophrenia must be carefully mapped out. Overall, we support further development of dual (or triple) hit models incorporating genetic, neurodevelopmental and appropriate environmental elements in the search for more aetiologically valid animal models of schizophrenia and neurodevelopmental disorders (NDDs).
Collapse
Affiliation(s)
- B Grayson
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK.
| | - S A Barnes
- Department of Psychiatry, University of California San Diego, 9500 Gilman Drive, La Jolla, San Diego, CA, 92093-0603, USA
| | - A Markou
- Department of Psychiatry, University of California San Diego, 9500 Gilman Drive, La Jolla, San Diego, CA, 92093-0603, USA
| | - C Piercy
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - G Podda
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - J C Neill
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| |
Collapse
|
32
|
Janhunen SK, Svärd H, Talpos J, Kumar G, Steckler T, Plath N, Lerdrup L, Ruby T, Haman M, Wyler R, Ballard TM. The subchronic phencyclidine rat model: relevance for the assessment of novel therapeutics for cognitive impairment associated with schizophrenia. Psychopharmacology (Berl) 2015; 232:4059-83. [PMID: 26070547 DOI: 10.1007/s00213-015-3954-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 04/27/2015] [Indexed: 12/26/2022]
Abstract
RATIONALE Current treatments for schizophrenia have modest, if any, efficacy on cognitive dysfunction, creating a need for novel therapies. Their development requires predictive animal models. The N-methyl-D-aspartate (NMDA) hypothesis of schizophrenia indicates the use of NMDA antagonists, like subchronic phencyclidine (scPCP) to model cognitive dysfunction in adult animals. OBJECTIVES The objective of this study was to assess the scPCP model by (1) reviewing published findings of scPCP-induced neurochemical changes and effects on cognitive tasks in adult rats and (2) comparing findings from a multi-site study to determine scPCP effects on standard and touchscreen cognitive tasks. METHODS Across four research sites, the effects of scPCP (typically 5 mg/kg twice daily for 7 days, followed by at least 7-day washout) in adult male Lister Hooded rats were studied on novel object recognition (NOR) with 1-h delay, acquisition and reversal learning in Morris water maze and touchscreen-based visual discrimination. RESULTS Literature findings showed that scPCP impaired attentional set-shifting (ASST) and NOR in several labs and induced a variety of neurochemical changes across different labs. In the multi-site study, scPCP impaired NOR, but not acquisition or reversal learning in touchscreen or water maze. Yet, this treatment regimen induced locomotor hypersensitivity to acute PCP until 13-week post-cessation. CONCLUSIONS The multi-site study confirmed that scPCP impaired NOR and ASST only and demonstrated the reproducibility and usefulness of the touchscreen approach. Our recommendation, prior to testing novel therapeutics in the scPCP model, is to be aware that further work is required to understand the neurochemical changes and specificity of the cognitive deficits.
Collapse
Affiliation(s)
- Sanna K Janhunen
- CNS Research, Research and Development, Orion Pharma, Orion Corporation, Tengstrominkatu 8, P.O. Box 425, 20101, Turku, Finland.
| | - Heta Svärd
- CNS Research, Research and Development, Orion Pharma, Orion Corporation, Tengstrominkatu 8, P.O. Box 425, 20101, Turku, Finland
| | - John Talpos
- Janssen Research and Development, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - Gaurav Kumar
- Janssen Research and Development, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - Thomas Steckler
- Janssen Research and Development, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - Niels Plath
- Synaptic Transmission, H. Lundbeck A/S, Ottiliavej 9, 2500, Valby, Denmark
| | - Linda Lerdrup
- Synaptic Transmission, H. Lundbeck A/S, Ottiliavej 9, 2500, Valby, Denmark
| | - Trine Ruby
- Synaptic Transmission, H. Lundbeck A/S, Ottiliavej 9, 2500, Valby, Denmark
| | - Marie Haman
- Neuroscience, Ophthalmology and Rare Diseases, Roche Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070, Basel, Switzerland
| | - Roger Wyler
- Neuroscience, Ophthalmology and Rare Diseases, Roche Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070, Basel, Switzerland
| | - Theresa M Ballard
- Neuroscience, Ophthalmology and Rare Diseases, Roche Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070, Basel, Switzerland
| |
Collapse
|
33
|
Li JT, Zhao YY, Wang HL, Wang XD, Su YA, Si TM. Long-term effects of neonatal exposure to MK-801 on recognition memory and excitatory–inhibitory balance in rat hippocampus. Neuroscience 2015; 308:134-43. [DOI: 10.1016/j.neuroscience.2015.09.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 08/28/2015] [Accepted: 09/01/2015] [Indexed: 01/25/2023]
|
34
|
Stamenić TT, Joksimović S, Biawat P, Stanković T, Marković B, Cook JM, Savić MM. Negative modulation of α₅ GABAA receptors in rats may partially prevent memory impairment induced by MK-801, but not amphetamine- or MK-801-elicited hyperlocomotion. J Psychopharmacol 2015; 29:1013-24. [PMID: 26105958 PMCID: PMC4861997 DOI: 10.1177/0269881115590601] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Reportedly, negative modulation of α5 GABAA receptors may improve cognition in normal and pharmacologically-impaired animals, and such modulation has been proposed as an avenue for treatment of cognitive symptoms in schizophrenia. This study assessed the actions of PWZ-029, administered at doses (2, 5, and 10 mg/kg) at which it reached micromolar concentrations in brain tissue with estimated free concentrations adequate for selective modulation of α5 GABAA receptors, in three cognitive tasks in male Wistar rats acutely treated with the noncompetitive N-methyl-d-aspartate receptor antagonist, MK-801 (0.1 mg/kg), as well in tests of locomotor activity potentiated by MK-801 (0.2 mg/kg) or amphetamine (0.5 mg/kg). In a hormetic-like manner, only 5 mg/kg PWZ-029 reversed MK-801-induced deficits in novel object recognition test (visual recognition memory), whereas in the Morris water maze, the 2 mg/kg dose of PWZ-029 exerted partial beneficial effects on spatial learning impairment. PWZ-029 did not affect recognition memory deficits in social novelty discrimination procedure. Motor hyperactivity induced with MK-801 or amphetamine was not preventable by PWZ-029. Our results show that certain MK-801-induced memory deficits can be ameliorated by negative modulation of α5 GABAA receptors, and point to the need for further elucidation of their translational relevance to cognitive deterioration in schizophrenia.
Collapse
Affiliation(s)
| | - Srdjan Joksimović
- Department of Pharmacology, University of Belgrade, Belgrade, Serbia
| | - Poonam Biawat
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Tamara Stanković
- Department of Pharmacology, University of Belgrade, Belgrade, Serbia
| | - Bojan Marković
- Department of Pharmaceutical Chemistry, University of Belgrade, Belgrade, Serbia
| | - James M Cook
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Miroslav M Savić
- Department of Pharmacology, University of Belgrade, Belgrade, Serbia
| |
Collapse
|
35
|
Redrobe JP, Rasmussen LK, Christoffersen CT, Bundgaard C, Jørgensen M. Characterisation of Lu AF33241: A novel, brain-penetrant, dual inhibitor of phosphodiesterase (PDE) 2A and PDE10A. Eur J Pharmacol 2015; 761:79-85. [DOI: 10.1016/j.ejphar.2015.04.040] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 04/01/2015] [Accepted: 04/16/2015] [Indexed: 11/26/2022]
|
36
|
Ling I, Mihalik B, Etherington LA, Kapus G, Pálvölgyi A, Gigler G, Kertész S, Gaál A, Pallagi K, Kiricsi P, Szabó É, Szénási G, Papp L, Hársing LG, Lévay G, Spedding M, Lambert JJ, Belelli D, Barkóczy J, Volk B, Simig G, Gacsályi I, Antoni FA. A novel GABA(A) alpha 5 receptor inhibitor with therapeutic potential. Eur J Pharmacol 2015; 764:497-507. [PMID: 26169564 DOI: 10.1016/j.ejphar.2015.07.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 06/30/2015] [Accepted: 07/01/2015] [Indexed: 10/23/2022]
Abstract
Novel 2,3-benzodiazepine and related isoquinoline derivatives, substituted at position 1 with a 2-benzothiophenyl moiety, were synthesized to produce compounds that potently inhibited the action of GABA on heterologously expressed GABAA receptors containing the alpha 5 subunit (GABAA α5), with no apparent affinity for the benzodiazepine site. Substitutions of the benzothiophene moiety at position 4 led to compounds with drug-like properties that were putative inhibitors of extra-synaptic GABAA α5 receptors and had substantial blood-brain barrier permeability. Initial characterization in vivo showed that 8-methyl-5-[4-(trifluoromethyl)-1-benzothiophen-2-yl]-1,9-dihydro-2H-[1,3]oxazolo[4,5-h][2,3]benzodiazepin-2-one was devoid of sedative, pro-convulsive or motor side-effects, and enhanced the performance of rats in the object recognition test. In summary, we have discovered a first-in-class GABA-site inhibitor of extra-synaptic GABAA α5 receptors that has promising drug-like properties and warrants further development.
Collapse
Affiliation(s)
- István Ling
- Chemical Research Division, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Balázs Mihalik
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Lori-An Etherington
- Division of Neuroscience, Medical Research Institute, Ninewells Hospital & Medical School, Dundee University, Dundee, Scotland, UK
| | - Gábor Kapus
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Adrienn Pálvölgyi
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Gábor Gigler
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Szabolcs Kertész
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Attila Gaál
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Katalin Pallagi
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Péter Kiricsi
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Éva Szabó
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Gábor Szénási
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Lilla Papp
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - László G Hársing
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - György Lévay
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | | | - Jeremy J Lambert
- Division of Neuroscience, Medical Research Institute, Ninewells Hospital & Medical School, Dundee University, Dundee, Scotland, UK
| | - Delia Belelli
- Division of Neuroscience, Medical Research Institute, Ninewells Hospital & Medical School, Dundee University, Dundee, Scotland, UK
| | - József Barkóczy
- Chemical Research Division, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Balázs Volk
- Chemical Research Division, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Gyula Simig
- Chemical Research Division, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - István Gacsályi
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary
| | - Ferenc A Antoni
- Division of Preclinical Research, Egis Pharmaceuticals PLC, Budapest, Hungary.
| |
Collapse
|
37
|
Hammer H, Bader BM, Ehnert C, Bundgaard C, Bunch L, Hoestgaard-Jensen K, Schroeder OHU, Bastlund JF, Gramowski-Voß A, Jensen AA. A Multifaceted GABAA Receptor Modulator: Functional Properties and Mechanism of Action of the Sedative-Hypnotic and Recreational Drug Methaqualone (Quaalude). Mol Pharmacol 2015; 88:401-20. [PMID: 26056160 DOI: 10.1124/mol.115.099291] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Accepted: 06/08/2015] [Indexed: 01/09/2023] Open
Abstract
In the present study, we have elucidated the functional characteristics and mechanism of action of methaqualone (2-methyl-3-o-tolyl-4(3H)-quinazolinone, Quaalude), an infamous sedative-hypnotic and recreational drug from the 1960s-1970s. Methaqualone was demonstrated to be a positive allosteric modulator at human α1,2,3,5β2,3γ2S GABAA receptors (GABAARs) expressed in Xenopus oocytes, whereas it displayed highly diverse functionalities at the α4,6β1,2,3δ GABAAR subtypes, ranging from inactivity (α4β1δ), through negative (α6β1δ) or positive allosteric modulation (α4β2δ, α6β2,3δ), to superagonism (α4β3δ). Methaqualone did not interact with the benzodiazepine, barbiturate, or neurosteroid binding sites in the GABAAR. Instead, the compound is proposed to act through the transmembrane β((+))/α((-)) subunit interface of the receptor, possibly targeting a site overlapping with that of the general anesthetic etomidate. The negligible activities displayed by methaqualone at numerous neurotransmitter receptors and transporters in an elaborate screening for additional putative central nervous system (CNS) targets suggest that it is a selective GABAAR modulator. The mode of action of methaqualone was further investigated in multichannel recordings from primary frontal cortex networks, where the overall activity changes induced by the compound at 1-100 μM concentrations were quite similar to those mediated by other CNS depressants. Finally, the free methaqualone concentrations in the mouse brain arising from doses producing significant in vivo effects in assays for locomotion and anticonvulsant activity correlated fairly well with its potencies as a modulator at the recombinant GABAARs. Hence, we propose that the multifaceted functional properties exhibited by methaqualone at GABAARs give rise to its effects as a therapeutic and recreational drug.
Collapse
Affiliation(s)
- Harriet Hammer
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (H.H., L.B., K.H.-J., A.A.J.); NeuroProof, Rostock, Germany (B.M.B., C.E., O.H.-U.S., A.G.-V.); and H. Lundbeck A/S, Valby, Denmark (C.B., J.F.B.)
| | - Benjamin M Bader
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (H.H., L.B., K.H.-J., A.A.J.); NeuroProof, Rostock, Germany (B.M.B., C.E., O.H.-U.S., A.G.-V.); and H. Lundbeck A/S, Valby, Denmark (C.B., J.F.B.)
| | - Corina Ehnert
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (H.H., L.B., K.H.-J., A.A.J.); NeuroProof, Rostock, Germany (B.M.B., C.E., O.H.-U.S., A.G.-V.); and H. Lundbeck A/S, Valby, Denmark (C.B., J.F.B.)
| | - Christoffer Bundgaard
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (H.H., L.B., K.H.-J., A.A.J.); NeuroProof, Rostock, Germany (B.M.B., C.E., O.H.-U.S., A.G.-V.); and H. Lundbeck A/S, Valby, Denmark (C.B., J.F.B.)
| | - Lennart Bunch
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (H.H., L.B., K.H.-J., A.A.J.); NeuroProof, Rostock, Germany (B.M.B., C.E., O.H.-U.S., A.G.-V.); and H. Lundbeck A/S, Valby, Denmark (C.B., J.F.B.)
| | - Kirsten Hoestgaard-Jensen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (H.H., L.B., K.H.-J., A.A.J.); NeuroProof, Rostock, Germany (B.M.B., C.E., O.H.-U.S., A.G.-V.); and H. Lundbeck A/S, Valby, Denmark (C.B., J.F.B.)
| | - Olaf H-U Schroeder
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (H.H., L.B., K.H.-J., A.A.J.); NeuroProof, Rostock, Germany (B.M.B., C.E., O.H.-U.S., A.G.-V.); and H. Lundbeck A/S, Valby, Denmark (C.B., J.F.B.)
| | - Jesper F Bastlund
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (H.H., L.B., K.H.-J., A.A.J.); NeuroProof, Rostock, Germany (B.M.B., C.E., O.H.-U.S., A.G.-V.); and H. Lundbeck A/S, Valby, Denmark (C.B., J.F.B.)
| | - Alexandra Gramowski-Voß
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (H.H., L.B., K.H.-J., A.A.J.); NeuroProof, Rostock, Germany (B.M.B., C.E., O.H.-U.S., A.G.-V.); and H. Lundbeck A/S, Valby, Denmark (C.B., J.F.B.)
| | - Anders A Jensen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (H.H., L.B., K.H.-J., A.A.J.); NeuroProof, Rostock, Germany (B.M.B., C.E., O.H.-U.S., A.G.-V.); and H. Lundbeck A/S, Valby, Denmark (C.B., J.F.B.)
| |
Collapse
|
38
|
Tse MT, Piantadosi PT, Floresco SB. Prefrontal cortical gamma-aminobutyric acid transmission and cognitive function: drawing links to schizophrenia from preclinical research. Biol Psychiatry 2015; 77:929-39. [PMID: 25442792 DOI: 10.1016/j.biopsych.2014.09.007] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 08/22/2014] [Accepted: 09/15/2014] [Indexed: 12/28/2022]
Abstract
Cognitive dysfunction in schizophrenia is one of the most pervasive and debilitating aspects of the disorder. Among the numerous neural abnormalities that may contribute to schizophrenia symptoms, perturbations in markers for the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), particularly within the frontal lobes, are some of the most reliable alterations observed at postmortem examination. However, how prefrontal GABA dysfunction contributes to cognitive impairment in schizophrenia remains unclear. We provide an overview of postmortem GABAergic perturbations in the brain affected by schizophrenia and describe circumstantial evidence linking these alterations to cognitive dysfunction. In addition, we conduct a survey of studies using neurodevelopmental, genetic, and pharmacologic rodent models that induce schizophrenia-like cognitive impairments, highlighting the convergence of these mechanistically distinct approaches to prefrontal GABAergic disruption. We review preclinical studies that have directly targeted prefrontal cortical GABAergic transmission using local application of GABAA receptor antagonists. These studies have provided an important link between GABA transmission and cognitive dysfunction in schizophrenia because they show that reducing prefrontal inhibitory transmission induces various cognitive, emotional, and dopaminergic abnormalities that resemble aspects of the disorder. These converging clinical and preclinical findings provide strong support for the idea that perturbations in GABA signaling drive certain forms of cognitive dysfunction in schizophrenia. Future studies using this approach will yield information to refine further a putative "GABA hypothesis" of schizophrenia.
Collapse
Affiliation(s)
- Maric T Tse
- Department of Psychology and Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Patrick T Piantadosi
- Department of Psychology and Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stan B Floresco
- Department of Psychology and Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.
| |
Collapse
|
39
|
Richetto J, Labouesse MA, Poe MM, Cook JM, Grace AA, Riva MA, Meyer U. Behavioral effects of the benzodiazepine-positive allosteric modulator SH-053-2'F-S-CH₃ in an immune-mediated neurodevelopmental disruption model. Int J Neuropsychopharmacol 2015; 18:pyu055. [PMID: 25636893 PMCID: PMC4360215 DOI: 10.1093/ijnp/pyu055] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Impaired γ-aminobutyric acid (GABA) signaling may contribute to the emergence of cognitive deficits and subcortical dopaminergic hyperactivity in patients with schizophrenia and related psychotic disorders. Against this background, it has been proposed that pharmacological interventions targeting GABAergic dysfunctions may prove useful in correcting such cognitive impairments and dopaminergic imbalances. METHODS Here, we explored possible beneficial effects of the benzodiazepine-positive allosteric modulator SH-053-2'F-S-CH₃, with partial selectivity at the α2, α3, and α5 subunits of the GABAA receptor in an immune-mediated neurodevelopmental disruption model. The model is based on prenatal administration of the viral mimetic polyriboinosinic-polyribocytidilic acid [poly(I:C)] in mice, which is known to capture various GABAergic, dopamine-related, and cognitive abnormalities implicated in schizophrenia and related disorders. RESULTS Real-time polymerase chain reaction analyses confirmed the expected alterations in GABAA receptor α subunit gene expression in the medial prefrontal cortices and ventral hippocampi of adult poly(I:C) offspring relative to control offspring. Systemic administration of SH-053-2'F-S-CH₃ failed to normalize the poly(I:C)-induced deficits in working memory and social interaction, but instead impaired performance in these cognitive and behavioral domains both in control and poly(I:C) offspring. In contrast, SH-053-2'F-S-CH₃ was highly effective in mitigating the poly(I:C)-induced amphetamine hypersensitivity phenotype without causing side effects in control offspring. CONCLUSIONS Our preclinical data suggest that benzodiazepine-like positive allosteric modulators with activity at the α2, α3, and α5 subunits of the GABAA receptor may be particularly useful in correcting pathological overactivity of the dopaminergic system, but they may be ineffective in targeting multiple pathological domains that involve the co-existence of psychotic, social, and cognitive dysfunctions.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Urs Meyer
- Center of Neuropharmacology, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy (Drs Richetto and Riva); Physiology and Behavior Laboratory, ETH Zurich, Schorenstrasse 16, 8603 Schwerzenbach, Switzerland (Drs Labouesse and Meyer); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI (Drs Poe and Cook); Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA (Dr Grace); Center of Excellence on Neurodegenerative Diseases, Università degli Studi di Milano, Milan, Italy (Dr Riva).
| |
Collapse
|
40
|
Redrobe JP, Jørgensen M, Christoffersen CT, Montezinho LP, Bastlund JF, Carnerup M, Bundgaard C, Lerdrup L, Plath N. In vitro and in vivo characterisation of Lu AF64280, a novel, brain penetrant phosphodiesterase (PDE) 2A inhibitor: potential relevance to cognitive deficits in schizophrenia. Psychopharmacology (Berl) 2014; 231:3151-67. [PMID: 24577516 DOI: 10.1007/s00213-014-3492-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Accepted: 02/05/2014] [Indexed: 12/25/2022]
Abstract
Here, we present the pharmacological characterisation of Lu AF64280, a novel, selective, brain penetrant phosphodiesterase (PDE) 2A inhibitor, in in vitro/in vivo assays indicative of PDE2A inhibition, and in vivo models/assays relevant to cognitive processing or antipsychotic-like activity. The in vitro selectivity of Lu AF64280 was determined against a panel of PDE enzymes and 3',5'-cyclic guanosine monophosphate (cGMP) levels in the hippocampus were determined using in vivo microdialysis. Lu AF64280 potently inhibited hPDE2A (Ki = 20 nM), 50-fold above moderate inhibition of both hPDE9A (Ki = 1,000 nM) and hPDE10A (Ki = 1,800 nM), and displayed a >250-fold selectivity over all other full-length human recombinant PDE family members (Ki above 5,000 nM). Lu AF64280 (20 mg/kg) significantly increased cGMP levels in the hippocampus (p < 0.01 versus vehicle-treated mice), attenuated sub-chronic phencyclidine-induced deficits in novel object exploration in rats (10 mg/kg, p < 0.001 versus vehicle-treated), blocked early postnatal phencyclidine-induced deficits in the intradimensional/extradimensional shift task in rats (1 and 10 mg/kg, p < 0.001 versus vehicle-treated) and attenuated spontaneous P20-N40 auditory gating deficits in DBA/2 mice (20 mg/kg, p < 0.05 versus vehicle-treated). In contrast, Lu AF64280 failed to attenuate phencyclidine-induced hyperactivity in mice, and was devoid of antipsychotic-like activity in the conditioned avoidance response paradigm in rats, at any dose tested. Lu AF64280 represents a novel tool compound for selective PDE2A inhibition that substantiates a critical role of this enzyme in cognitive processes under normal and pathological conditions.
Collapse
Affiliation(s)
- John P Redrobe
- Neuroscience Research DK, H. Lundbeck A/S, Ottiliavej 9, Valby, 2500, Copenhagen, Denmark
| | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Blom SM, Rottländer M, Kehler J, Bundgaard C, Schmitt N, Jensen HS. From pan-reactive KV7 channel opener to subtype selective opener/inhibitor by addition of a methyl group. PLoS One 2014; 9:e100209. [PMID: 24956197 PMCID: PMC4067310 DOI: 10.1371/journal.pone.0100209] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 05/22/2014] [Indexed: 01/24/2023] Open
Abstract
The voltage-gated potassium channels of the KV7 family (KV7.1–5) play important roles in controlling neuronal excitability and are therefore attractive targets for treatment of CNS disorders linked to hyperexcitability. One of the main challenges in developing KV7 channel active drugs has been to identify compounds capable of discriminating between the neuronally expressed subtypes (KV7.2–5), aiding the identification of the subunit composition of KV7 currents in various tissues, and possessing better therapeutic potential for particular indications. By taking advantage of the structure-activity relationship of acrylamide KV7 channel openers and the effects of these compounds on mutant KV7 channels, we have designed and synthesized a novel KV7 channel modulator with a unique profile. The compound, named SMB-1, is an inhibitor of KV7.2 and an activator of KV7.4. SMB-1 inhibits KV7.2 by reducing the current amplitude and increasing the time constant for the slow component of the activation kinetics. The activation of KV7.4 is seen as an increase in the current amplitude and a slowing of the deactivation kinetics. Experiments studying mutant channels with a compromised binding site for the KV7.2–5 opener retigabine indicate that SMB-1 binds within the same pocket as retigabine for both inhibition of KV7.2 and activation of KV7.4. SMB-1 may serve as a valuable tool for KV7 channel research and may be used as a template for further design of better subtype selective KV7 channel modulators. A compound with this profile could hold novel therapeutic potential such as the treatment of both positive and cognitive symptoms in schizophrenia.
Collapse
Affiliation(s)
- Sigrid Marie Blom
- Division of Neuroscience Drug Discovery, H. Lundbeck A/S, Copenhagen, Denmark
- Department of Biomedical Sciences and Danish National Research Foundation Centre for Cardiac Arrhythmia, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mario Rottländer
- Division of Discovery Chemistry and DMPK, H. Lundbeck A/S, Copenhagen, Denmark
| | - Jan Kehler
- Division of Discovery Chemistry and DMPK, H. Lundbeck A/S, Copenhagen, Denmark
| | | | - Nicole Schmitt
- Department of Biomedical Sciences and Danish National Research Foundation Centre for Cardiac Arrhythmia, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Henrik Sindal Jensen
- Division of Neuroscience Drug Discovery, H. Lundbeck A/S, Copenhagen, Denmark
- * E-mail:
| |
Collapse
|
42
|
Gaskin PLR, Alexander SPH, Fone KCF. Neonatal phencyclidine administration and post-weaning social isolation as a dual-hit model of 'schizophrenia-like' behaviour in the rat. Psychopharmacology (Berl) 2014; 231:2533-45. [PMID: 24402141 DOI: 10.1007/s00213-013-3424-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 12/16/2013] [Indexed: 01/07/2023]
Abstract
RATIONALE Schizophrenia is a debilitating disorder comprising positive, negative and cognitive deficits with a poorly defined neurobiological aetiology; therefore, animal models with greater translational reliability are essential to develop improved therapies. OBJECTIVES This study combines two developmental challenges in rats, neonatal phencyclidine (PCP) injection and subsequent rearing in social isolation from weaning, to attempt to produce more robust behavioural deficits with greater translational relevance to schizophrenia than either challenge alone. METHODS Forty-two male Lister-hooded rat pups received the N-methyl-D-aspartate (NMDA) receptor antagonist, phencyclidine (PCP, 10 mg/kg, s.c.), or vehicle on post-natal day (PND) 7, 9 and 11 and were weaned on PND 23 into group housing (saline-treated n = 11 or PCP-treated n = 10) or isolation (saline n = 10 or PCP n = 11). Six weeks post-weaning, novelty- and PCP-induced (3.2 mg/kg) locomotor activity, novel object discrimination, prepulse inhibition of acoustic startle and contextual memory in a conditioned emotion response (CER) were recorded. RESULTS Isolation rearing alone significantly elevated baseline locomotor activity and induced visual recognition memory impairment in novel object discrimination. Neonatal PCP treatment did not induce locomotor sensitisation to a subsequent acute PCP injection, but it impaired prepulse inhibition when combined with isolation rearing. CER freezing behaviour was significantly reduced by isolation rearing but an even greater effect occurred when combined with neonatal PCP treatment. CONCLUSIONS Neonatal PCP and isolation rearing both produce behavioural deficits in adult rats, but combined treatment caused a wider range of more severe cognitive impairments, providing a more comprehensive preclinical model to determine the neurobiological aetiology of schizophrenia than either treatment alone.
Collapse
Affiliation(s)
- Philip L R Gaskin
- School of Life Sciences, Medical School, Queen's Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK
| | | | | |
Collapse
|
43
|
Gardner RJ, Kersanté F, Jones MW, Bartsch U. Neural oscillations during non-rapid eye movement sleep as biomarkers of circuit dysfunction in schizophrenia. Eur J Neurosci 2014; 39:1091-106. [DOI: 10.1111/ejn.12533] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Revised: 01/06/2014] [Accepted: 01/29/2014] [Indexed: 12/25/2022]
Affiliation(s)
- Richard J. Gardner
- School of Physiology and Pharmacology; University of Bristol; Medical Sciences Building University Walk Bristol BS8 1TD UK
| | - Flavie Kersanté
- School of Physiology and Pharmacology; University of Bristol; Medical Sciences Building University Walk Bristol BS8 1TD UK
| | - Matthew W. Jones
- School of Physiology and Pharmacology; University of Bristol; Medical Sciences Building University Walk Bristol BS8 1TD UK
| | - Ullrich Bartsch
- School of Physiology and Pharmacology; University of Bristol; Medical Sciences Building University Walk Bristol BS8 1TD UK
| |
Collapse
|
44
|
Brisch R, Saniotis A, Wolf R, Bielau H, Bernstein HG, Steiner J, Bogerts B, Braun K, Jankowski Z, Kumaratilake J, Henneberg M, Gos T, Henneberg M, Gos T. The role of dopamine in schizophrenia from a neurobiological and evolutionary perspective: old fashioned, but still in vogue. Front Psychiatry 2014; 5:47. [PMID: 24904434 PMCID: PMC4032934 DOI: 10.3389/fpsyt.2014.00047] [Citation(s) in RCA: 178] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 04/23/2014] [Indexed: 12/12/2022] Open
Abstract
Dopamine is an inhibitory neurotransmitter involved in the pathology of schizophrenia. The revised dopamine hypothesis states that dopamine abnormalities in the mesolimbic and prefrontal brain regions exist in schizophrenia. However, recent research has indicated that glutamate, GABA, acetylcholine, and serotonin alterations are also involved in the pathology of schizophrenia. This review provides an in-depth analysis of dopamine in animal models of schizophrenia and also focuses on dopamine and cognition. Furthermore, this review provides not only an overview of dopamine receptors and the antipsychotic effects of treatments targeting them but also an outline of dopamine and its interaction with other neurochemical models of schizophrenia. The roles of dopamine in the evolution of the human brain and human mental abilities, which are affected in schizophrenia patients, are also discussed.
Collapse
Affiliation(s)
- Ralf Brisch
- Department of Forensic Medicine, Medical University of Gdańsk , Gdańsk , Poland
| | - Arthur Saniotis
- School of Medical Sciences, The University of Adelaide , Adelaide, SA , Australia ; Centre for Evolutionary Medicine, University of Zurich , Zurich , Switzerland
| | - Rainer Wolf
- Department of Psychiatry and Psychotherapy, Ruhr University Bochum , Bochum , Germany
| | - Hendrik Bielau
- Department of Psychiatry, Otto-von-Guericke-University of Magdeburg , Magdeburg , Germany
| | - Hans-Gert Bernstein
- Department of Psychiatry, Otto-von-Guericke-University of Magdeburg , Magdeburg , Germany
| | - Johann Steiner
- Department of Psychiatry, Otto-von-Guericke-University of Magdeburg , Magdeburg , Germany
| | - Bernhard Bogerts
- Department of Psychiatry, Otto-von-Guericke-University of Magdeburg , Magdeburg , Germany
| | - Katharina Braun
- Department of Zoology, Institute of Biology, Otto-von-Guericke-University of Magdeburg , Magdeburg , Germany
| | - Zbigniew Jankowski
- Department of Forensic Medicine, Medical University of Gdańsk , Gdańsk , Poland
| | - Jaliya Kumaratilake
- Biological Anthropology and Comparative Anatomy Research Unit, School of Biomedical Sciences, The University of Adelaide , Adelaide, SA , Australia
| | - Maciej Henneberg
- Biological Anthropology and Comparative Anatomy Research Unit, School of Biomedical Sciences, The University of Adelaide , Adelaide, SA , Australia
| | - Tomasz Gos
- Department of Forensic Medicine, Medical University of Gdańsk , Gdańsk , Poland
| | - Maciej Henneberg
- Biological Anthropology and Comparative Anatomy Research Unit, School of Biomedical Sciences, The University of Adelaide , Adelaide, SA , Australia
| | - Tomasz Gos
- Department of Forensic Medicine, Medical University of Gdańsk , Gdańsk , Poland
| |
Collapse
|
45
|
Eskildsen J, Redrobe JP, Sams AG, Dekermendjian K, Laursen M, Boll JB, Papke RL, Bundgaard C, Frederiksen K, Bastlund JF. Discovery and optimization of Lu AF58801, a novel, selective and brain penetrant positive allosteric modulator of alpha-7 nicotinic acetylcholine receptors: attenuation of subchronic phencyclidine (PCP)-induced cognitive deficits in rats following oral administration. Bioorg Med Chem Lett 2013; 24:288-93. [PMID: 24291041 DOI: 10.1016/j.bmcl.2013.11.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 11/07/2013] [Accepted: 11/10/2013] [Indexed: 11/16/2022]
Abstract
In this Letter, we describe a chemical lead optimization campaign starting from a novel, weak α7 nicotinic acetylcholine receptor positive allosteric modulator (PAM) hit from a HTS screen. Exploration of the structure-activity relationships for α7 PAM potency, intrinsic hepatic clearance, the structure-property relationships for lipophilicity, and thermodynamic solubility, led to the identification of Lu AF58801: a potent, orally available, brain penetrant PAM of the α7 nicotinic acetylcholine receptor, showing efficacy in a novel object recognition task in rats treated subchronically with phencyclidine (PCP).
Collapse
Affiliation(s)
- Jørgen Eskildsen
- Neuroscience Research DK, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark.
| | - John P Redrobe
- Neuroscience Research DK, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | - Anette G Sams
- Neuroscience Research DK, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | - Kim Dekermendjian
- Neuroscience Research DK, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | - Morten Laursen
- Neuroscience Research DK, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | - Jette B Boll
- Neuroscience Research DK, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | - Roger L Papke
- Department of Pharmacology, University of Florida College of Medicine, Gainesville, FL, USA
| | | | - Kristen Frederiksen
- Neuroscience Research DK, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | - Jesper F Bastlund
- Neuroscience Research DK, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| |
Collapse
|
46
|
Egawa K, Fukuda A. Pathophysiological power of improper tonic GABA(A) conductances in mature and immature models. Front Neural Circuits 2013; 7:170. [PMID: 24167475 PMCID: PMC3807051 DOI: 10.3389/fncir.2013.00170] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 09/28/2013] [Indexed: 11/25/2022] Open
Abstract
High-affinity extrasynaptic gamma-aminobutyric acid A (GABAA) receptors are tonically activated by low and consistent levels of ambient GABA, mediating chronic inhibition against neuronal excitability (tonic inhibition) and the modulation of neural development. Synaptic (phasic) inhibition is spatially and temporally precise compared with tonic inhibition, which provides blunt yet strong integral inhibitory force by shunting electrical signaling. Although effects of acute modification of tonic inhibition are known, its pathophysiological significance remains unclear because homeostatic regulation of neuronal excitability can compensate for long-term deficit of extrasynaptic GABAA receptor activation. Nevertheless, tonic inhibition is of great interest for its pathophysiological involvement in central nervous system (CNS) diseases and thus as a therapeutic target. Together with the development of experimental models for various pathological states, recent evidence demonstrates such pathological involvements of tonic inhibition in neuronal dysfunction. This review focuses on the recent progress of tonic activation of GABAA conductance on the development and pathology of the CNS. Findings indicate that neuronal function in various brain regions are exacerbated with a gain or loss of function of tonic inhibition by GABA spillover. Disturbance of tonic GABAA conductance mediated by non-synaptic ambient GABA may result in brain mal-development. Therefore, various pathological states (epilepsy, motor dysfunctions, psychiatric disorders, and neurodevelopmental disorders) may be partly attributable to abnormal tonic GABAA conductances. Thus, the tone of tonic conductance and level of ambient GABA may be precisely tuned to maintain the regular function and development of the CNS. Therefore, receptor expression and factors for regulating the ambient GABA concentration are highlighted to gain a deeper understanding of pathology and therapeutic strategy for CNS diseases.
Collapse
Affiliation(s)
- Kiyoshi Egawa
- Department of Neurology, Massachusetts General Hospital Charlestown, MA, USA ; Department of Pediatrics, Hokkaido University Graduate School of Medicine Sapporo, Japan
| | | |
Collapse
|
47
|
Rudolph U, Möhler H. GABAA receptor subtypes: Therapeutic potential in Down syndrome, affective disorders, schizophrenia, and autism. Annu Rev Pharmacol Toxicol 2013; 54:483-507. [PMID: 24160694 DOI: 10.1146/annurev-pharmtox-011613-135947] [Citation(s) in RCA: 231] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The γ-aminobutyric acid (GABA) system plays a pivotal role in orchestrating the synchronicity of local networks and the functional coupling of different brain regions. Here we review the impact of the GABAA receptor subtypes on cognitive and emotional behavior, paying particular attention to five disease states: cognitive dysfunction and Down syndrome, anxiety disorders, depression, schizophrenia, and autism. Through the bidirectional modulation of tonic inhibition, α5-subunit-containing GABAA receptors permit the bidirectional modulation of cognitive processes, and a partial inverse agonist acting at the α5-subunit-containing GABAA receptor is in a clinical trial in individuals with Down syndrome. With regard to anxiety disorders, the viability of nonsedative anxiolytics based on the modulation of α2- and α3-subunit-containing GABAA receptors has been established in clinical proof-of-concept trials. Regarding the remaining three disease states, the GABA hypothesis of depression offers new options for antidepressant drug development; cognitive symptoms in schizophrenia are attributed to a cortical GABAergic deficit, and dysfunctional GABAergic inhibition is increasingly understood to contribute to the pathophysiology of autism spectrum disorders.
Collapse
Affiliation(s)
- Uwe Rudolph
- Laboratory of Genetic Neuropharmacology, McLean Hospital and Department of Psychiatry, Harvard Medical School, Belmont, Massachusetts 02478;
| | | |
Collapse
|
48
|
Broberg BV, Madsen KH, Plath N, Olsen CK, Glenthøj BY, Paulson OB, Bjelke B, Søgaard LV. A schizophrenia rat model induced by early postnatal phencyclidine treatment and characterized by Magnetic Resonance Imaging. Behav Brain Res 2013; 250:1-8. [DOI: 10.1016/j.bbr.2013.04.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 04/18/2013] [Accepted: 04/20/2013] [Indexed: 12/15/2022]
|
49
|
Enhanced interaction among ErbB4, PSD-95 and NMDAR by chronic MK-801 treatment is associated with behavioral abnormalities. Pharmacol Biochem Behav 2013; 108:44-53. [DOI: 10.1016/j.pbb.2013.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 04/04/2013] [Accepted: 04/11/2013] [Indexed: 11/19/2022]
|
50
|
Bundgaard C, Badolo L, Redrobe JP. RO4938581, a GABAAα5 modulator, displays strong CYP1A2 autoinduction properties in rats. Biochem Pharmacol 2013; 85:1363-9. [PMID: 23415905 DOI: 10.1016/j.bcp.2013.02.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 02/05/2013] [Accepted: 02/05/2013] [Indexed: 10/27/2022]
Abstract
Autoinduction in drug metabolism is a known phenomenon observed when a drug induces the enzymes responsible for its own metabolism. The potency, rate and extent of autoinduction following a given treatment paradigm may have therapeutic implications in clinic as well as for in vivo pharmacological assessments in animals. RO4938581, an imidazo-triazolo-benzodiazepine, is a novel GABAAα5 negative modulator recently pursued for the treatment of cognitive dysfunctions. As circulating plasma levels of RO4938581 were shown to decrease rapidly after repeated dosing in rats, with CYP1A2 being involved in the metabolism of the compound, we examined the potential role of RO4938581-mediated autoinduction of CYP1A2. Incubation of rat hepatocytes with RO4938581 revealed potent CYP1A2 induction with significant increase in enzymatic activity at concentrations of 0.1nM and RO4938581 was shown to be 700-fold more potent than β-napththoflavone. Ex vivo studies revealed a 7-fold increase in metabolic CYP1A2 activity in liver microsomes prepared from rats administered with 0.1mg/kg of RO4938581 24h before. This induction profile was reflected in vivo in pharmacokinetic studies in rats where an 8-fold reduction in plasma exposure was observed after a second dose. The reduction in plasma exposures due to CYP1A2 autoinduction were confirmed functionally in contextual fear conditioning paradigm in rats, where a positive pharmacological effect observed after acute drug administration disappeared completely after sub-chronic dosing. Together, these findings suggest that RO4938581 possesses potent CYP1A2 autoinductive properties in rats and may serve as a tool for mechanistic metabolism or drug-drug interaction studies encircling this enzyme in rats.
Collapse
|