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Nuwer JL, Povysheva N, Jacob TC. Long-term α5 GABA A receptor negative allosteric modulator treatment reduces NMDAR-mediated neuronal excitation and maintains basal neuronal inhibition. Neuropharmacology 2023; 237:109587. [PMID: 37270156 PMCID: PMC10527172 DOI: 10.1016/j.neuropharm.2023.109587] [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: 03/27/2023] [Revised: 04/27/2023] [Accepted: 05/09/2023] [Indexed: 06/05/2023]
Abstract
α5 subunit-containing GABA type-A receptors (α5 GABAARs) are enriched in the hippocampus and play critical roles in neurodevelopment, synaptic plasticity, and cognition. α5 GABAAR preferring negative allosteric modulators (α5 NAMs) show promise mitigating cognitive impairment in preclinical studies of conditions characterized by excess GABAergic inhibition, including Down syndrome and memory deficits post-anesthesia. However, previous studies have primarily focused on acute application or single-dose α5 NAM treatment. Here, we measured the effects of chronic (7-day) in vitro treatment with L-655,708 (L6), a highly selective α5 NAM, on glutamatergic and GABAergic synapses in rat hippocampal neurons. We previously showed that 2-day in vitro treatment with L6 enhanced synaptic levels of the glutamate NMDA receptor (NMDAR) GluN2A subunit without modifying surface α5 GABAAR expression, inhibitory synapse function, or L6 sensitivity. We hypothesized that chronic L6 treatment would further increase synaptic GluN2A subunit levels while maintaining GABAergic inhibition and L6 efficacy, thus increasing neuronal excitation and glutamate-evoked intracellular calcium responses. Immunofluorescence experiments revealed that 7-day L6 treatment slightly increased the synaptic levels of gephyrin and surface α5 GABAARs. Functional studies showed that chronic α5 NAM treatment did not alter inhibition or α5 NAM sensitivity. Surprisingly, chronic L6 exposure decreased surface levels of GluN2A and GluN2B subunits, concurrent with reduced NMDAR-mediated neuronal excitation as seen by faster synaptic decay rates and reduced glutamate-evoked calcium responses. Together, these results show that chronic in vitro treatment with an α5 NAM leads to subtle homeostatic changes in inhibitory and excitatory synapses that suggest an overall dampening of excitability.
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Affiliation(s)
- Jessica L Nuwer
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Nadya Povysheva
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Tija C Jacob
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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2
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Luscher B, Maguire JL, Rudolph U, Sibille E. GABA A receptors as targets for treating affective and cognitive symptoms of depression. Trends Pharmacol Sci 2023; 44:586-600. [PMID: 37543478 PMCID: PMC10511219 DOI: 10.1016/j.tips.2023.06.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 06/23/2023] [Accepted: 06/23/2023] [Indexed: 08/07/2023]
Abstract
In the past 20 years, our understanding of the pathophysiology of depression has evolved from a focus on an imbalance of monoaminergic neurotransmitters to a multifactorial picture including an improved understanding of the role of glutamatergic excitatory and GABAergic inhibitory neurotransmission. FDA-approved treatments targeting the glutamatergic [esketamine for major depressive disorder (MDD)] and GABAergic (brexanolone for peripartum depression) systems have become available. This review focuses on the GABAA receptor (GABAAR) system as a target for novel antidepressants and discusses the mechanisms by which modulation of δ-containing GABAARs with neuroactive steroids (NASs) or of α5-containing GABAARs results in antidepressant or antidepressant-like actions and discusses clinical data on NASs. Moreover, a potential mechanism by which α5-GABAAR-positive allosteric modulators (PAMs) may improve cognitive deficits in depression is presented.
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Affiliation(s)
- Bernhard Luscher
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA; Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA; Department of Psychiatry, Pennsylvania State University, University Park, PA 16802, USA; Penn State Neuroscience Institute, Pennsylvania State University, University Park, PA 16802, USA
| | - Jamie L Maguire
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Uwe Rudolph
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61802, USA; Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61802, USA.
| | - Etienne Sibille
- Campbell Family Mental Health Research Institute of the Centre for Addiction and Mental Health, University of Toronto, Toronto, ON, Canada; Department of Psychiatry, University of Toronto, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
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3
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Troppoli TA, Zanos P, Georgiou P, Gould TD, Rudolph U, Thompson SM. Negative Allosteric Modulation of Gamma-Aminobutyric Acid A Receptors at α5 Subunit-Containing Benzodiazepine Sites Reverses Stress-Induced Anhedonia and Weakened Synaptic Function in Mice. Biol Psychiatry 2022; 92:216-226. [PMID: 35120711 PMCID: PMC9198111 DOI: 10.1016/j.biopsych.2021.11.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 11/12/2021] [Accepted: 11/23/2021] [Indexed: 12/20/2022]
Abstract
BACKGROUND Abnormal reward processing, typically anhedonia, is a hallmark of human depression and is accompanied by altered functional connectivity in reward circuits. Negative allosteric modulators of GABAA (gamma-aminobutyric acid A) receptors (GABA-NAMs) have rapid antidepressant-like properties in rodents and exert few adverse effects, but molecular targets underlying their behavioral and synaptic effects remain undetermined. We hypothesized that GABA-NAMs act at the benzodiazepine site of GABAA receptors containing α5 subunits to increase gamma oscillatory activity, strengthen synapses in reward circuits, and reverse anhedonia. METHODS Anhedonia was induced by chronic stress in male mice and assayed by preferences for sucrose and female urine (n = 5-7 mice/group). Hippocampal slices were then prepared for electrophysiological recording (n = 1-6 slices/mouse, 4-6 mice/group). Electroencephalography power was quantified in response to GABA-NAM and ketamine administration (n = 7-9 mice/group). RESULTS Chronic stress reduced sucrose and female urine preferences and hippocampal temporoammonic-CA1 synaptic strength. A peripheral injection of the GABA-NAM MRK-016 restored hedonic behavior and AMPA-to-NMDA ratios in wild-type mice. These actions were prevented by pretreatment with the benzodiazepine site antagonist flumazenil. MRK-016 administration increased gamma power over the prefrontal cortex in wild-type mice but not α5 knockout mice, whereas ketamine promoted gamma power in both genotypes. Hedonic behavior and AMPA-to-NMDA ratios were only restored by MRK-016 in stressed wild-type mice but not α5 knockout mice. CONCLUSIONS α5-Selective GABA-NAMs exert rapid anti-anhedonic actions and restore the strength of synapses in reward regions by acting at the benzodiazepine site of α5-containing GABAA receptors. These results encourage human studies using GABA-NAMs to treat depression by providing readily translatable measures of target engagement.
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Affiliation(s)
- Timothy A. Troppoli
- Department of Physiology, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD 21201,Molecular Medicine Program, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD 21201
| | - Panos Zanos
- Department of Psychiatry, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD 21201,Current address: Department of Psychology, University of Cyprus, 1 Panepistimiou Avenue, Aglantzia, 2109, PO Box 1678, Nicosia, Cyprus
| | - Polymnia Georgiou
- Department of Psychiatry, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD 21201
| | - Todd D. Gould
- Department of Psychiatry, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD 21201,Department of Anatomy & Neurobiology, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD 21201,Department of Pharmacology, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD 21201,Veterans Affairs Maryland Health Care System, Baltimore, MD, 21201
| | - Uwe Rudolph
- Department of Comparative Biosciences and Carl R. Woese Institute for Genomic Biology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, 2001 S Lincoln Ave, Urbana, IL 61802-6178
| | - Scott M. Thompson
- Department of Physiology, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD 21201,Department of Psychiatry, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD 21201,To whom correspondence should be addressed:
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Cai X, Qiu L, Wang C, Yang H, Zhou Z, Mao M, Zhu Y, Wen Y, Cai W, Zhu W, Sun J. Hippocampal Inhibitory Synapsis Deficits Induced by α5-Containing GABA A Receptors Mediate Chronic Neuropathic Pain-Related Cognitive Impairment. Mol Neurobiol 2022; 59:6049-6061. [PMID: 35849280 DOI: 10.1007/s12035-022-02955-8] [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: 04/14/2022] [Accepted: 07/02/2022] [Indexed: 10/17/2022]
Abstract
Chronic neuropathic pain often leads to cognitive impairment, but the exact mechanism remains unclear. Gamma-aminobutyric acid A receptors (GABAARs) are the major inhibitory receptors in the brain, of which the α5-containing GABAARs (GABAARs-α5) are implicated in a range of neuropsychiatric disorders with cognitive deficits. However, whether GABAARs-α5 are involved in chronic neuropathic pain-related cognitive impairment remains unknown. In this study, the rats with chronic neuropathic pain induced by right sciatic nerve ligation injury (SNI) exhibited cognitive impairment with declined spontaneous alternation in Y-maze test and discrimination index in novel object recognition test. The GABAARs-α5 expressing on parvalbumin and somatostatin interneurons increased remarkably in hippocampus, resulting in decreased mean frequency of spontaneous inhibitory postsynaptic currents in hippocampal pyramidal neurons. Significantly, antagonizing the GABAARs-α5 by L655708 rescued weakened inhibitory synaptic transmission and cognitive impairment induced by chronic neuropathic pain. Taken together, these data suggest that the GABAARs-α5 play a crucial role in chronic neuropathic pain-induced cognitive impairment by weakening inhibitory synaptic transmission, which may provide insights into the pharmacologic treatment of chronic neuropathic pain-related cognitive impairment.
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Affiliation(s)
- Xuechun Cai
- Department of Anesthesiology and Perioperative Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China
| | - Lili Qiu
- Department of Anesthesiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, Jiangsu, People's Republic of China
| | - Chaoran Wang
- Department of Anesthesiology and Perioperative Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China
| | - Hang Yang
- Department of Anesthesiology and Perioperative Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China
| | - Zhenhui Zhou
- Department of Anesthesiology and Perioperative Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China
| | - Meng Mao
- Department of Anesthesiology, Department of Anesthesiology, The Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Yunqing Zhu
- Department of Anesthesiology and Perioperative Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China
| | - Yazhou Wen
- Department of Anesthesiology, Nanjing Maternity and Child Health Care Hospital, Nanjing, Jiangsu, People's Republic of China
| | - Wenlan Cai
- Department of Anesthesiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, Jiangsu, People's Republic of China
| | - Wei Zhu
- Department of Anesthesiology and Perioperative Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China.
| | - Jie Sun
- Department of Anesthesiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, Jiangsu, People's Republic of China.
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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.
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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
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6
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Fernández-Teruel A. From Inhibition of GABA-A Receptor-Mediated Synaptic Transmission by Conventional Antidepressants to Negative Allosteric Modulators of Alpha5-GABA-A Receptors as Putative Fast-Acting Antidepressant Drugs: Closing the Circle? Curr Neuropharmacol 2021; 20:85-89. [PMID: 34736382 PMCID: PMC9199546 DOI: 10.2174/1570159x19666211104144650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 08/18/2021] [Accepted: 10/14/2021] [Indexed: 11/22/2022] Open
Abstract
The present perspective paper shortly and specifically addresses the issues of whether inhibition of GABA-A receptor-mediated synaptic transmission may be involved in antidepressant-like actions and the therapeutic effects of conventional antidepressant (AD) drugs, and whether the recent development of negative allosteric modulators (NAMs) of the alpha5-GABA-A receptor may constitute significant progress in our knowledge on the neurobiology and the treatment of depression.
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Affiliation(s)
- Alberto Fernández-Teruel
- Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Autonomous University of Barcelona, 08193-Bellaterra, Barcelona. Sri Lanka
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7
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Nuwer JL, Brady ML, Povysheva NV, Coyne A, Jacob TC. Sustained treatment with an α5 GABA A receptor negative allosteric modulator delays excitatory circuit development while maintaining GABAergic neurotransmission. Neuropharmacology 2021; 197:108724. [PMID: 34284042 DOI: 10.1016/j.neuropharm.2021.108724] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 07/01/2021] [Accepted: 07/14/2021] [Indexed: 01/02/2023]
Abstract
α5 subunit GABA type A receptor (GABAAR) preferring negative allosteric modulators (NAMs) are cognitive enhancers with antidepressant-like effects. α5-NAM success in treating mouse models of neurodevelopmental disorders with excessive inhibition have led to Phase 2 clinical trials for Down syndrome. Despite in vivo efficacy, no study has examined the effects of continued α5-NAM treatment on inhibitory and excitatory synapse plasticity to identify mechanisms of action. Here we used L-655,708, an imidazobenzodiazepine that acts as a highly selective but weak α5-NAM, to investigate the impact of sustained treatment on hippocampal neuron synapse and dendrite development. We show that 2-day pharmacological reduction of α5-GABAAR signaling from DIV12-14, when GABAARs contribute to depolarization, delays dendritic spine maturation and the NMDA receptor (NMDAR) GluN2B/GluN2A developmental shift. In contrast, α5-NAM treatment from DIV19-21, when hyperpolarizing GABAAR signaling predominates, enhances surface synaptic GluN2A while decreasing GluN2B. Despite changes in NMDAR subtype surface levels and localization, total levels of key excitatory synapse proteins were largely unchanged, and mEPSCs were unaltered. Importantly, 2-day α5-NAM treatment does not alter the total surface levels or distribution of α5-GABAARs, reduce the gephyrin inhibitory synaptic scaffold, or impair phasic or tonic inhibition. Furthermore, α5-NAM inhibition of the GABAAR tonic current in mature neurons is maintained after 2-day α5-NAM treatment, suggesting reduced tolerance liability, in contrast to other clinically relevant GABAAR-targeting drugs such as benzodiazepines. Together, these results show that α5-GABAARs contribute to dendritic spine maturation and excitatory synapse development via a NMDAR dependent mechanism without perturbing overall neuronal excitability.
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Affiliation(s)
- Jessica L Nuwer
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Megan L Brady
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Nadya V Povysheva
- Department of Neuroscience and Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Amanda Coyne
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Tija C Jacob
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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8
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Fee C, Prevot TD, Misquitta K, Knutson DE, Li G, Mondal P, Cook JM, Banasr M, Sibille E. Behavioral Deficits Induced by Somatostatin-Positive GABA Neuron Silencing Are Rescued by Alpha 5 GABA-A Receptor Potentiation. Int J Neuropsychopharmacol 2021; 24:505-518. [PMID: 33438026 PMCID: PMC8278801 DOI: 10.1093/ijnp/pyab002] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 12/15/2020] [Accepted: 01/11/2021] [Indexed: 11/13/2022] Open
Abstract
INTRODUCTION Deficits in somatostatin-positive gamma-aminobutyric acid interneurons (SST+ GABA cells) are commonly reported in human studies of mood and anxiety disorder patients. A causal link between SST+ cell dysfunction and symptom-related behaviors has been proposed based on rodent studies showing that chronic stress, a major risk factor for mood and anxiety disorders, induces a low SST+ GABA cellular phenotype across corticolimbic brain regions; that lowering Sst, SST+ cell, or GABA functions induces depressive-/anxiety-like behaviors (a rodent behavioral construct collectively defined as "behavioral emotionality"); and that disinhibiting SST+ cells has antidepressant-like effects. Recent studies found that compounds preferentially potentiating receptors mediating SST+ cell functions, α5-GABAA receptor positive allosteric modulators (α5-PAMs), achieved antidepressant-like effects. Together, the evidence suggests that SST+ cells regulate mood and cognitive functions that are disrupted in mood disorders and that rescuing SST+ cell function via α5-PAM may represent a targeted therapeutic strategy. METHODS We developed a mouse model allowing chemogenetic manipulation of brain-wide SST+ cells and employed behavioral characterization 30 minutes after repeated acute silencing to identify contributions to symptom-related behaviors. We then assessed whether an α5-PAM, GL-II-73, could rescue behavioral deficits. RESULTS Brain-wide SST+ cell silencing induced features of stress-related illnesses, including elevated neuronal activity and plasma corticosterone levels, increased anxiety- and anhedonia-like behaviors, and impaired short-term memory. GL-II-73 led to antidepressant- and anxiolytic-like improvements among behavioral deficits induced by brain-wide SST+ cell silencing. CONCLUSION Our data validate SST+ cells as regulators of mood and cognitive functions and demonstrate that bypassing low SST+ cell function via α5-PAM represents a targeted therapeutic strategy.
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Affiliation(s)
- Corey Fee
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada,Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Thomas D Prevot
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada,Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Keith Misquitta
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada,Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Daniel E Knutson
- Department of Chemistry and Biochemistry, University of Wisconsin–Milwaukee, Milwaukee, Wisconsin, USA
| | - Guanguan Li
- Department of Chemistry and Biochemistry, University of Wisconsin–Milwaukee, Milwaukee, Wisconsin, USA,Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, College of Science, Southern University of Science and Technology, Shenzhen, China
| | - Prithu Mondal
- Department of Chemistry and Biochemistry, University of Wisconsin–Milwaukee, Milwaukee, Wisconsin, USA
| | - James M Cook
- Department of Chemistry and Biochemistry, University of Wisconsin–Milwaukee, Milwaukee, Wisconsin, USA
| | - Mounira Banasr
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada,Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Etienne Sibille
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada,Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada,Correspondence: Etienne Sibille, PhD, CAMH, 250 College Street, Room 134, Toronto, ON M5T 1R8, Canada ()
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