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Ge Y, Craig AM. Haploinsufficiency of GABA A Receptor-Associated Clptm1 Enhances Phasic and Tonic Inhibitory Neurotransmission, Suppresses Excitatory Synaptic Plasticity, and Impairs Memory. J Neurosci 2024; 44:e0521242024. [PMID: 38942471 PMCID: PMC11308325 DOI: 10.1523/jneurosci.0521-24.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 06/17/2024] [Accepted: 06/20/2024] [Indexed: 06/30/2024] Open
Abstract
The mechanisms utilized by neurons to regulate the efficacy of phasic and tonic inhibition and their impacts on synaptic plasticity and behavior are incompletely understood. Cleft lip and palate transmembrane protein 1 (Clptm1) is a membrane-spanning protein that interacts with multiple γ-aminobutyric acid type A receptor (GABAAR) subunits, trapping them in the endoplasmic reticulum and Golgi network. Overexpression and knock-down studies suggest that Clptm1 modulates GABAAR-mediated phasic inhibition and tonic inhibition as well as activity-induced inhibitory synaptic homeostasis in cultured hippocampal neurons. To investigate the role of Clptm1 in the modulation of GABAARs in vivo, we generated Clptm1 knock-out (KO) mice. Here, we show that genetic KO of Clptm1 elevated phasic and tonic inhibitory transmission in both male and female heterozygous mice. Although basal excitatory synaptic transmission was not affected, Clptm1 haploinsufficiency significantly blocked high-frequency stimulation-induced long-term potentiation (LTP) in hippocampal CA3→CA1 synapses. In the hippocampus-dependent contextual fear-conditioning behavior task, both male and female Clptm1 heterozygous KO mice exhibited impairment in contextual fear memory. In addition, LTP and contextual fear memory were rescued by application of L-655,708, a negative allosteric modulator of the extrasynaptic GABAAR α5 subunit. These results suggest that haploinsufficiency of Clptm1 contributes to cognitive deficits through altered synaptic transmission and plasticity by elevation of inhibitory neurotransmission, with tonic inhibition playing a major role.
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Affiliation(s)
- Yuan Ge
- Djavad Mowafaghian Centre for Brain Health and Department of Psychiatry, University of British Columbia, Vancouver, British Columbia V6T 2B5, Canada
| | - Ann Marie Craig
- Djavad Mowafaghian Centre for Brain Health and Department of Psychiatry, University of British Columbia, Vancouver, British Columbia V6T 2B5, Canada
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Ju YH, Cho J, Park JY, Kim H, Hong EB, Park KD, Lee CJ, Chung E, Kim HI, Nam MH. Tonic excitation by astrocytic GABA causes neuropathic pain by augmenting neuronal activity and glucose metabolism. Exp Mol Med 2024; 56:1193-1205. [PMID: 38760512 PMCID: PMC11148027 DOI: 10.1038/s12276-024-01232-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 02/21/2024] [Accepted: 02/29/2024] [Indexed: 05/19/2024] Open
Abstract
Neuropathic pain is a debilitating condition caused by the hyperexcitability of spinal dorsal horn neurons and is often characterized by allodynia. Although neuron-independent mechanisms of hyperexcitability have been investigated, the contribution of astrocyte-neuron interactions remains unclear. Here, we show evidence of reactive astrocytes and their excessive GABA release in the spinal dorsal horn, which paradoxically leads to the tonic excitation of neighboring neurons in a neuropathic pain model. Using multiple electrophysiological methods, we demonstrated that neuronal hyperexcitability is attributed to both increased astrocytic GABA synthesis via monoamine oxidase B (MAOB) and the depolarized reversal potential of GABA-mediated currents (EGABA) via the downregulation of the neuronal K+/Cl- cotransporter KCC2. Furthermore, longitudinal 2-deoxy-2-[18F]-fluoro-D-glucose microPET imaging demonstrated increased regional glucose metabolism in the ipsilateral dorsal horn, reflecting neuronal hyperexcitability. Importantly, inhibiting MAOB restored the entire astrocytic GABA-mediated cascade and abrogated the increased glucose metabolism and mechanical allodynia. Overall, astrocytic GABA-mediated tonic excitation is critical for neuronal hyperexcitability, leading to mechanical allodynia and neuropathic pain.
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Affiliation(s)
- Yeon Ha Ju
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Jongwook Cho
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Ji-Young Park
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Hyunjin Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Eun-Bin Hong
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Ki Duk Park
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - C Justin Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, 34126, Republic of Korea
| | - Euiheon Chung
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Hyoung-Ihl Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea.
- Department of Neurosurgery, Presbyterian Medical Center, Jeonju, 54987, Republic of Korea.
| | - Min-Ho Nam
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.
- Department of KHU-KIST Convergence Science and Technology, Kyung Hee University, Seoul, 02447, Republic of Korea.
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Xin Y, Chu T, Zhou S, Xu A. α5GABA A receptor: A potential therapeutic target for perioperative neurocognitive disorders, a review of preclinical studies. Brain Res Bull 2023; 205:110821. [PMID: 37984621 DOI: 10.1016/j.brainresbull.2023.110821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 11/14/2023] [Accepted: 11/17/2023] [Indexed: 11/22/2023]
Abstract
Perioperative neurocognitive disorders (PND) are a common complication in elderly patients following surgery, which not only prolongs the recovery period but also affects their future quality of life and imposes a significant burden on their family and society. Multiple factors, including aging, vulnerability, anesthetic drugs, cerebral oxygen desaturation, and severe pain, have been associated with PND. Unfortunately, no effective drug is currently available to prevent PND. α5 γ-aminobutyric acid subtype A (α5GABAA) receptors have been implicated in cognitive function modulation. Positive or negative allosteric modulators of α5GABAA receptors have been found to improve cognitive impairment under different conditions. Therefore, targeting α5GABAA receptors may represent a promising treatment strategy for PND. This review focuses on preclinical studies of α5GABAA receptors and the risk factors associated with PND, primarily including aging, anesthetics, and neuroinflammation. Specifically, positive allosteric modulators of α5GABAA receptors have improved cognitive function in aged experimental animals. In contrast, negative allosteric modulators of α5GABAA receptors have been found to facilitate cognitive recovery in aged or adult experimental animals undergoing anesthesia and surgery but not in aged experimental animals under anesthesia alone. The reasons for the discordant findings have yet to be elucidated. In preclinical studies, different strategies of drug administration, as well as various behavioral tests, may influence the stability of the results. These issues need to be carefully considered in future studies.
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Affiliation(s)
- Yueyang Xin
- Department of Anesthesiology, Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, and Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Tiantian Chu
- Department of Anesthesiology, Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, and Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Siqi Zhou
- Department of Anesthesiology, Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, and Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Aijun Xu
- Department of Anesthesiology, Hubei Key Laboratory of Geriatric Anesthesia and Perioperative Brain Health, and Wuhan Clinical Research Center for Geriatric Anesthesia, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, China.
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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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Torres-López C, Cuartero MI, García-Culebras A, de la Parra J, Fernández-Valle ME, Benito M, Vázquez-Reyes S, Jareño-Flores T, de Castro-Millán FJ, Hurtado O, Buckwalter MS, García-Segura JM, Lizasoain I, Moro MA. Ipsilesional Hippocampal GABA Is Elevated and Correlates With Cognitive Impairment and Maladaptive Neurogenesis After Cortical Stroke in Mice. Stroke 2023; 54:2652-2665. [PMID: 37694402 DOI: 10.1161/strokeaha.123.043516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 08/09/2023] [Indexed: 09/12/2023]
Abstract
BACKGROUND Cognitive dysfunction is a frequent stroke sequela, but its pathogenesis and treatment remain unresolved. Involvement of aberrant hippocampal neurogenesis and maladaptive circuitry remodeling has been proposed, but their mechanisms are unknown. Our aim was to evaluate potential underlying molecular/cellular events implicated. METHODS Stroke was induced by permanent occlusion of the middle cerebral artery occlusion in 2-month-old C57BL/6 male mice. Hippocampal metabolites/neurotransmitters were analyzed longitudinally by in vivo magnetic resonance spectroscopy. Cognitive function was evaluated with the contextual fear conditioning test. Microglia, astrocytes, neuroblasts, interneurons, γ-aminobutyric acid (GABA), and c-fos were analyzed by immunofluorescence. RESULTS Approximately 50% of mice exhibited progressive post-middle cerebral artery occlusion cognitive impairment. Notably, immature hippocampal neurons in the impaired group displayed more severe aberrant phenotypes than those from the nonimpaired group. Using magnetic resonance spectroscopy, significant bilateral changes in hippocampal metabolites, such as myo-inositol or N-acetylaspartic acid, were found that correlated, respectively, with numbers of glia and immature neuroblasts in the ischemic group. Importantly, some metabolites were specifically altered in the ipsilateral hippocampus suggesting its involvement in aberrant hippocampal neurogenesis and remodeling processes. Specifically, middle cerebral artery occlusion animals with higher hippocampal GABA levels displayed worse cognitive outcome. Implication of GABA in this setting was supported by the amelioration of ischemia-induced memory deficits and aberrant hippocampal neurogenesis after blocking pharmacologically GABAergic neurotransmission, an intervention which was ineffective when neurogenesis was inhibited. These data suggest that GABA exerts its detrimental effect, at least partly, by affecting morphology and integration of newborn neurons into the hippocampal circuits. CONCLUSIONS Hippocampal GABAergic neurotransmission could be considered a novel diagnostic and therapeutic target for poststroke cognitive impairment.
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Affiliation(s)
- Cristina Torres-López
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
- Instituto Universitario de Investigación en Neuroquímica (C.T.-L., M.I.C., A.G.-C., J.M.G.-S., I.L.), Universidad Complutense de Madrid (UCM), Spain
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., I.L., M.A.M.)
| | - Maria I Cuartero
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Instituto Universitario de Investigación en Neuroquímica (C.T.-L., M.I.C., A.G.-C., J.M.G.-S., I.L.), Universidad Complutense de Madrid (UCM), Spain
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., I.L., M.A.M.)
| | - Alicia García-Culebras
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
- Instituto Universitario de Investigación en Neuroquímica (C.T.-L., M.I.C., A.G.-C., J.M.G.-S., I.L.), Universidad Complutense de Madrid (UCM), Spain
- Departamento de Biología Celular, Facultad de Medicina (A.G.-C.), Universidad Complutense de Madrid (UCM), Spain
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., I.L., M.A.M.)
| | - Juan de la Parra
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
| | - María E Fernández-Valle
- Infraestructura Científica y Técnica Singular (ICTS) Centro de Bioimagen Complutense (M.E.F.-V., J.M.G.-S.), Universidad Complutense de Madrid (UCM), Spain
| | - Marina Benito
- Hospital Nacional de Parapléjicos de Toledo, Spain (M.B.)
| | - Sandra Vázquez-Reyes
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
| | - Tania Jareño-Flores
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
| | - Francisco J de Castro-Millán
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
| | - Olivia Hurtado
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
| | - Marion S Buckwalter
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, CA (M.S.B.)
| | - Juan M García-Segura
- Instituto Universitario de Investigación en Neuroquímica (C.T.-L., M.I.C., A.G.-C., J.M.G.-S., I.L.), Universidad Complutense de Madrid (UCM), Spain
- Infraestructura Científica y Técnica Singular (ICTS) Centro de Bioimagen Complutense (M.E.F.-V., J.M.G.-S.), Universidad Complutense de Madrid (UCM), Spain
- Departamento de Bioquímica y Biología Molecular (J.M.G.-S.), Universidad Complutense de Madrid (UCM), Spain
| | - Ignacio Lizasoain
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
- Instituto Universitario de Investigación en Neuroquímica (C.T.-L., M.I.C., A.G.-C., J.M.G.-S., I.L.), Universidad Complutense de Madrid (UCM), Spain
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., I.L., M.A.M.)
| | - María A Moro
- Neurovascular Pathophysiology, Cardiovascular Risk Factor and Brain Function Programme, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., S.V.-R., T.J.-F., F.J.d.C.-M., O.H., M.A.M.)
- Unidad de Investigación Neurovascular, Departamento de Farmacología, Facultad de Medicina (C.T.-L., M.I.C., A.G.-C., J.d.l.P., S.V.-R., T.J.-F., F.J.d.C.-M., I.L., M.A.M.), Universidad Complutense de Madrid (UCM), Spain
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain (C.T.-L., M.I.C., A.G.-C., I.L., M.A.M.)
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Bailey AM, Barrett A, Havens L, Leyder E, Merchant T, Starnes H, Thompson SM. Changes in social, sexual, and hedonic behaviors in rats in response to stress and restoration by a negative allosteric modulator of α5-subunit containing GABA receptor. Behav Brain Res 2023; 452:114554. [PMID: 37356670 PMCID: PMC10528636 DOI: 10.1016/j.bbr.2023.114554] [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: 12/28/2022] [Revised: 06/07/2023] [Accepted: 06/21/2023] [Indexed: 06/27/2023]
Abstract
Major depressive disorder (MDD) is a debilitating and costly human condition. Treatment for MDD relies heavily on the use of antidepressants that are slow to produce mood-related changes and are not effective in all patients, such as selective serotonin reuptake inhibitors (SSRIs). Several novel compounds, including negative allosteric modulators of GABA-A receptors containing the α5-subunit (GABA-NAMs), are under investigation for potential fast acting therapeutic use in MDD. Preclinical evidence that these compounds produce a rapid antidepressant-like response comes primarily from simple tests of escape behavior and preference for rewarding stimuli after chronic stress. To increase the ethological relevance of these compounds, we tested the hypothesis that the GABA-NAM, L-655,708, would produce an antidepressant-like response in more complex stress-sensitive social and sex behaviors, which are of relevance to the symptoms of human depression. In male rats subjected to chronic restraint stress, injection of L-655,708 increased reward in a sexual conditioned place preference task, increased male sexual activity with a receptive female, and re-established male social dominance hierarchies within 24 h. We also report increased sucrose preference in the social defeat stress (SDS) model of depression following GABA-NAM administration, demonstrating that its antidepressant-like actions are independent of the type of chronic stress administered. This work extends the impact of GABA-NAMs beyond traditional tests of anhedonia and further supports the development of alpha5 subunit-selective GABA-NAMs as a potential fast-acting therapeutic approach for treating human MDD.
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Affiliation(s)
- Aileen M Bailey
- Department of Psychology, St. Mary's College of Maryland, St. Mary's City, MD, United States.
| | - Allison Barrett
- Department of Psychology, St. Mary's College of Maryland, St. Mary's City, MD, United States
| | - Lane Havens
- Department of Psychology, St. Mary's College of Maryland, St. Mary's City, MD, United States
| | - Erica Leyder
- Department of Psychology, St. Mary's College of Maryland, St. Mary's City, MD, United States
| | - Taylor Merchant
- Department of Psychology, St. Mary's College of Maryland, St. Mary's City, MD, United States
| | - Hannah Starnes
- Department of Psychology, St. Mary's College of Maryland, St. Mary's City, MD, United States
| | - Scott M Thompson
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, United States; Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO, United States
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7
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Wyroślak M, Dobrzański G, Mozrzymas JW. Bidirectional plasticity of GABAergic tonic inhibition in hippocampal somatostatin- and parvalbumin-containing interneurons. Front Cell Neurosci 2023; 17:1193383. [PMID: 37448697 PMCID: PMC10336215 DOI: 10.3389/fncel.2023.1193383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 06/05/2023] [Indexed: 07/15/2023] Open
Abstract
GABAA receptors present in extrasynaptic areas mediate tonic inhibition in hippocampal neurons regulating the performance of neural networks. In this study, we investigated the effect of NMDA-induced plasticity on tonic inhibition in somatostatin- and parvalbumin-containing interneurons. Using pharmacological methods and transgenic mice (SST-Cre/PV-Cre x Ai14), we induced the plasticity of GABAergic transmission in somatostatin- and parvalbumin-containing interneurons by a brief (3 min) application of NMDA. In the whole-cell patch-clamp configuration, we measured tonic currents enhanced by specific agonists (etomidate or gaboxadol). Furthermore, in both the control and NMDA-treated groups, we examined to what extent these changes depend on the regulation of distinct subtypes of GABAA receptors. Tonic conductance in the somatostatin-containing (SST+) interneurons is enhanced after NMDA application, and the observed effect is associated with an increased content of α5-containing GABAARs. Both fast-spiking and non-fast-spiking parvalbumin-positive (PV+) cells showed a reduction of tonic inhibition after plasticity induction. This effect was accompanied in both PV+ interneuron types by a strongly reduced proportion of δ-subunit-containing GABAARs and a relatively small increase in currents mediated by α5-containing GABAARs. Both somatostatin- and parvalbumin-containing interneurons show cell type-dependent and opposite sign plasticity of tonic inhibition. The underlying mechanisms depend on the cell-specific balance of plastic changes in the contents of α5 and δ subunit-containing GABAARs.
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Affiliation(s)
- Marcin Wyroślak
- Department of Biophysics and Neuroscience, Wroclaw Medical University, Wrocław, Poland
| | | | - Jerzy W. Mozrzymas
- Department of Biophysics and Neuroscience, Wroclaw Medical University, Wrocław, Poland
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8
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Szabó G, Károlyi BI, Vaskó ÁG, Potor A, Vukics K, Kapus GL, Fodor L, Bobok A, Vastag M, Bata I. Identification of Triazolopyridines as Selective α5-GABA A Receptor Negative Allosteric Modulators by a Hybridization Approach. ACS Chem Neurosci 2023; 14:148-158. [PMID: 36524695 DOI: 10.1021/acschemneuro.2c00608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The identification and characterization of novel triazolopyridine derivatives with selective α5 subunit-containing GABAA receptor negative allosteric modulator (NAM) activity are disclosed. As a result of in silico screening of our corporate compound deck, we identified a moderately potent hit that was converted to an advanced hit bearing better physicochemical and pharmacological properties using a hybridization approach. Subsequent optimization led to the identification of in vitro potent and subtype-selective α5-GABAA receptor NAMs representing a new chemotype in this area.
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Affiliation(s)
- György Szabó
- Chemistry Division, Gedeon Richter Plc, P.O. Box 27, Budapest 10H-1475, Hungary
| | | | | | - Attila Potor
- Chemistry Division, Gedeon Richter Plc, P.O. Box 27, Budapest 10H-1475, Hungary
| | - Krisztina Vukics
- Chemistry Division, Gedeon Richter Plc, P.O. Box 27, Budapest 10H-1475, Hungary
| | - Gábor László Kapus
- Proprietary R&D Coordination Department, Gedeon Richter Plc, P.O. Box 27, Budapest 10H-1475, Hungary
| | - László Fodor
- Pharmacological & Drug Safety Research Department, Gedeon Richter Plc, P.O. Box 27, Budapest 10H-1475, Hungary
| | - Amrita Bobok
- Pharmacological & Drug Safety Research Department, Gedeon Richter Plc, P.O. Box 27, Budapest 10H-1475, Hungary
| | - Mónika Vastag
- Pharmacological & Drug Safety Research Department, Gedeon Richter Plc, P.O. Box 27, Budapest 10H-1475, Hungary
| | - Imre Bata
- Chemistry Division, Gedeon Richter Plc, P.O. Box 27, Budapest 10H-1475, Hungary
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9
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Sato Y, Schmitt O, Ip Z, Rabiller G, Omodaka S, Tominaga T, Yazdan-Shahmorad A, Liu J. Pathological changes of brain oscillations following ischemic stroke. J Cereb Blood Flow Metab 2022; 42:1753-1776. [PMID: 35754347 PMCID: PMC9536122 DOI: 10.1177/0271678x221105677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 04/01/2022] [Accepted: 05/17/2022] [Indexed: 11/16/2022]
Abstract
Brain oscillations recorded in the extracellular space are among the most important aspects of neurophysiology data reflecting the activity and function of neurons in a population or a network. The signal strength and patterns of brain oscillations can be powerful biomarkers used for disease detection and prediction of the recovery of function. Electrophysiological signals can also serve as an index for many cutting-edge technologies aiming to interface between the nervous system and neuroprosthetic devices and to monitor the efficacy of boosting neural activity. In this review, we provided an overview of the basic knowledge regarding local field potential, electro- or magneto- encephalography signals, and their biological relevance, followed by a summary of the findings reported in various clinical and experimental stroke studies. We reviewed evidence of stroke-induced changes in hippocampal oscillations and disruption of communication between brain networks as potential mechanisms underlying post-stroke cognitive dysfunction. We also discussed the promise of brain stimulation in promoting post stroke functional recovery via restoring neural activity and enhancing brain plasticity.
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Affiliation(s)
- Yoshimichi Sato
- Department of Neurological Surgery, UCSF, San Francisco, CA, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA, USA
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Oliver Schmitt
- Department of Anatomy, Medical School Hamburg, University of Applied Sciences and Medical University, Hamburg, Germany
| | - Zachary Ip
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Department of Electrical and Computer Engineering, University of Washington, Seattle, WA, USA
| | - Gratianne Rabiller
- Department of Neurological Surgery, UCSF, San Francisco, CA, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA, USA
| | - Shunsuke Omodaka
- Department of Neurological Surgery, UCSF, San Francisco, CA, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA, USA
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Teiji Tominaga
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Azadeh Yazdan-Shahmorad
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Department of Electrical and Computer Engineering, University of Washington, Seattle, WA, USA
| | - Jialing Liu
- Department of Neurological Surgery, UCSF, San Francisco, CA, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA, USA
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10
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McCoy AM, Prevot TD, Mian MY, Cook JM, Frazer A, Sibille EL, Carreno FR, Lodge DJ. Positive Allosteric Modulation of α5-GABAA Receptors Reverses Stress-Induced Alterations in Dopamine System Function and Prepulse Inhibition of Startle. Int J Neuropsychopharmacol 2022; 25:688-698. [PMID: 35732272 PMCID: PMC9380714 DOI: 10.1093/ijnp/pyac035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/24/2022] [Accepted: 06/21/2022] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Up to 64% of patients diagnosed with posttraumatic stress disorder (PTSD) experience psychosis, likely attributable to aberrant dopamine neuron activity. We have previously demonstrated that positive allosteric modulators of α5-GABAARs can selectively decrease hippocampal activity and reverse psychosis-like physiological and behavioral alterations in a rodent model used to study schizophrenia; however, whether this approach translates to a PTSD model remains to be elucidated. METHODS We utilized a 2-day inescapable foot shock (IS) procedure to induce stress-related pathophysiology in male Sprague-Dawley rats. We evaluated the effects of intra-ventral hippocampus (vHipp) administration GL-II-73, an α5-GABAAR, or viral overexpression of the α5 subunit, using in vivo electrophysiology and behavioral measures in control and IS-treated rats. RESULTS IS significantly increased ventral tegmental area dopamine neuron population activity, or the number of dopamine neurons firing spontaneously (n = 6; P = .016), consistent with observation in multiple rodent models used to study psychosis. IS also induced deficits in sensorimotor gating, as measured by reduced prepulse inhibition of startle (n = 12; P = .039). Interestingly, intra-vHipp administration of GL-II-73 completely reversed IS-induced increases in dopamine neuron population activity (n = 6; P = .024) and deficits in prepulse inhibition (n = 8; P = .025), whereas viral overexpression of the α5 subunit in the vHipp was not effective. CONCLUSIONS Our results demonstrate that pharmacological intervention augmenting α5-GABAAR function, but not α5 overexpression in itself, can reverse stress-induced deficits related to PTSD in a rodent model, providing a potential site of therapeutic intervention to treat comorbid psychosis in PTSD.
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Affiliation(s)
- Alexandra M McCoy
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, Texas, USA
- South Texas Veterans Health Care System, Audie L. Murphy Division, San Antonio, Texas, USA
| | - Thomas D Prevot
- Campbell Family Mental Health Research Institute of CAMH, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Md Yenus Mian
- 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
| | - Alan Frazer
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, Texas, USA
- South Texas Veterans Health Care System, Audie L. Murphy Division, San Antonio, Texas, USA
| | - Etienne L Sibille
- Campbell Family Mental Health Research Institute of CAMH, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Flavia R Carreno
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, Texas, USA
- South Texas Veterans Health Care System, Audie L. Murphy Division, San Antonio, Texas, USA
| | - Daniel J Lodge
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, Texas, USA
- South Texas Veterans Health Care System, Audie L. Murphy Division, San Antonio, Texas, USA
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11
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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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12
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Szabó G, Éliás O, Erdélyi P, Potor A, Túrós GI, Károlyi BI, Varró G, Vaskó ÁG, Bata I, Kapus GL, Dohányos Z, Bobok AÁ, Fodor L, Thán M, Vastag M, Komlódi Z, Soukupné Kedves RÉ, Makó É, Süveges B, Greiner I. Multiparameter Optimization of Naphthyridine Derivatives as Selective α5-GABA A Receptor Negative Allosteric Modulators. J Med Chem 2022; 65:7876-7895. [PMID: 35584373 DOI: 10.1021/acs.jmedchem.2c00414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The discovery and characterization of novel naphthyridine derivatives with selective α5-GABAAR negative allosteric modulator (NAM) activity are disclosed. Utilizing a scaffold-hopping strategy, fused [6 + 6] bicyclic scaffolds were designed and synthesized. Among these, 1,6-naphthyridinones were identified as potent and selective α5-GABAAR NAMs with metabolic stability, cardiac safety, and beneficial intellectual property (IP) issues. Relocation of the oxo acceptor function and subsequent modulation of the physicochemical properties resulted in novel 1,6-naphthyridines with improved profile, combining good potency, selectivity, ADME, and safety properties. Besides this, compound 20, having the most balanced profile, provided in vivo proof of concept (POC) for the new scaffold in two animal models of cognitive impairment associated with schizophrenia (CIAS).
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Affiliation(s)
- György Szabó
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - Olivér Éliás
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - Péter Erdélyi
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - Attila Potor
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - György I Túrós
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | | | - Gábor Varró
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - Ágnes Gy Vaskó
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - Imre Bata
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - Gábor L Kapus
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - Zoltán Dohányos
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - Amrita Á Bobok
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - László Fodor
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - Márta Thán
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - Mónika Vastag
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | - Zsolt Komlódi
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | | | - Éva Makó
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
| | | | - István Greiner
- Gedeon Richter Plc., 19-21. Gyömrői út, Budapest, 1103 Hungary
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13
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Bampali K, Koniuszewski F, Silva LL, Rehman S, Vogel FD, Seidel T, Scholze P, Zirpel F, Garon A, Langer T, Willeit M, Ernst M. Tricyclic antipsychotics and antidepressants can inhibit α5-containing GABA A receptors by two distinct mechanisms. Br J Pharmacol 2022; 179:3675-3692. [PMID: 35088415 PMCID: PMC9314015 DOI: 10.1111/bph.15807] [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: 04/06/2021] [Revised: 12/10/2021] [Accepted: 01/12/2022] [Indexed: 11/28/2022] Open
Abstract
Background and Purpose Many psychotherapeutic drugs, including clozapine, display polypharmacology and act on GABAA receptors. Patients with schizophrenia show alterations in function, structure and molecular composition of the hippocampus, and a recent study demonstrated aberrant levels of hippocampal α5 subunit‐containing GABAA receptors. The purpose of this study is to investigate the effects of tricyclic compounds on α5 subunit‐containing receptor subtypes. Experimental Approach Functional studies of effects by seven antipsychotic and antidepressant medications were performed in several GABAA receptor subtypes by two‐electrode voltage‐clamp electrophysiology using Xenopus laevis oocytes. Computational structural analysis was employed to design mutated constructs of the α5 subunit, probing a novel binding site. Radioligand displacement data complemented the functional and mutational findings. Key Results The antipsychotic drugs clozapine and chlorpromazine exerted functional inhibition on multiple GABAA receptor subtypes, including those containing α5‐subunits. Based on a chlorpromazine binding site observed in a GABA‐gated bacterial homologue, we identified a novel site in α5 GABAA receptor subunits and demonstrate differential usage of this and the orthosteric sites by these ligands. Conclusion and Implications Despite high molecular and functional similarities among the tested ligands, they reduce GABA currents by differential usage of allosteric and orthosteric sites. The chlorpromazine site we describe here is a new potential target for optimizing antipsychotic medications with beneficial polypharmacology. Further studies in defined subtypes are needed to substantiate mechanistic links between the therapeutic effects of clozapine and its action on certain GABAA receptor subtypes.
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Affiliation(s)
- Konstantina Bampali
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Filip Koniuszewski
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Luca L Silva
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Sabah Rehman
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Florian D Vogel
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Thomas Seidel
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Petra Scholze
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Florian Zirpel
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Arthur Garon
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Thierry Langer
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Matthäus Willeit
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Margot Ernst
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
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14
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Santrač A, Batinić B, Stamenić TT, Aranđelović J, Sharmin D, Knutson DE, Cook JM, Savić MM. Positive modulation of α5GABAA receptors leads to dichotomous effects in rats on memory pattern and GABRA5 expression in prefrontal cortex and hippocampus. Behav Brain Res 2022; 416:113578. [PMID: 34508769 DOI: 10.1016/j.bbr.2021.113578] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 08/22/2021] [Accepted: 09/06/2021] [Indexed: 01/04/2023]
Abstract
Positive allosteric modulators (PAMs) of α5GABAA receptors (α5GABAARs) are emerging as potential therapeutics for a range of neuropsychiatric disorders. However, their role in memory processing of healthy animals is not sufficiently examined. We tested the effects of MP-III-022 (1 mg/kg, 2.5 mg/kg and 10 mg/kg), a PAM known to be selective for α5GABAARs and devoid of prominent side-effects, in different behavioral paradigms (Morris water maze, novel object recognition test and social novelty discrimination) and on GABRA5 expression in Wistar rats, 30 min and 24 h after intraperitoneal treatment administration. The lowest dose tested worsened short-term object memory. The same dose, administered two times in a span of 24 h, improved spatial and impaired object and, at a trend level, social memory. The highest dose had a detrimental effect on all types of long-term memory (object memory at a trend level) and short-term spatial memory, but improved short-term object and social memory. Distinct sets of expression changes were detected in both prefrontal cortex and two regions of the hippocampus, but the latter ones could be assessed as more consequential. An increase of GABRA5 mRNA in CA2 occurred in parallel with improvement of object and social, but impairment of spatial memory, while the opposite happened with a trend level change in CA1. Our study demonstrates the variability of the roles of the α5GABAAR based on its level of expression and localization, in dependence on the type and protocol of cognitive tasks, as well as the respective timing of pharmacological modulation and testing.
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Affiliation(s)
- Anja Santrač
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia
| | - Bojan Batinić
- Department of Physiology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia
| | - Tamara Timić Stamenić
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia
| | - Jovana Aranđelović
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia
| | - Dishary Sharmin
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee and the Milwaukee Institute of Drug Discovery, P.O.Box 413, Milwaukee, WI 53201, USA
| | - Daniel E Knutson
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee and the Milwaukee Institute of Drug Discovery, P.O.Box 413, Milwaukee, WI 53201, USA
| | - James M Cook
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee and the Milwaukee Institute of Drug Discovery, P.O.Box 413, Milwaukee, WI 53201, USA
| | - Miroslav M Savić
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia.
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15
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Yuan C, Gao A, Xu Q, Zhang B, Xue R, Dou Y, Yu C. A multi-dosing regimen to enhance the spatial memory of normal rats with α5-containing GABA A receptor negative allosteric modulator L-655,708. Psychopharmacology (Berl) 2021; 238:3375-3389. [PMID: 34389882 DOI: 10.1007/s00213-021-05951-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 08/03/2021] [Indexed: 01/20/2023]
Abstract
RATIONALE AND OBJECTIVES The reported inconsistent effects of negative allosteric modulators of α5-containing GABAA receptors on learning and memory may be attributed to receptor selectivity, effective plasma concentration maintenance, and administration time. This study aimed to compare the effects of L-655,708 administered by single-dosing regimen versus multi-dosing regimen on spatial memory, signaling molecules, and brain functional connectivity. METHODS After comparing the maintenance time of the effective plasma concentration of L-655,708 between multi-dosing and single-dosing regimens, we further compared the effects of the administration of the two regimens at different phases (before-learning, during-learning, and before-probe) of the Morris water maze (MWM) test on the performance of learning and memory and the levels of signaling molecules related to learning and memory in hippocampal tissues. Functional connectivity analyses between hippocampal and cortical regions were performed to further clarify the effects of the multi-dosing regimen. RESULTS The multi-dosing regimen could maintain the effective plasma concentration of L-655,708 much longer than the single-dosing regimen. Only the multi-dosing regimen for L-655,708 administration during the learning period led to significant improvement in spatial memory in the MWM test and increases in levels of glutamate receptors and phosphorylated signaling molecules (p-PKAα, p-CaMKII, and p-CREB-1). Compared with the vehicle control, the multi-dosing regimen increased the functional connectivity of the left hippocampal CA1 with cingulate and motor cortices. CONCLUSIONS A multi-dosing regimen for L-655,708 administered during the learning period is an effective strategy to improve spatial memory, increase signaling molecule levels, and enhance the functional connectivity of the hippocampus.
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Affiliation(s)
- Congcong Yuan
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, 300052, People's Republic of China
| | - An Gao
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, 300052, People's Republic of China
| | - Qiang Xu
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, 300052, People's Republic of China
| | - Beibei Zhang
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, 300052, People's Republic of China
| | - Rui Xue
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, 300052, People's Republic of China
| | - Yan Dou
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, 300052, People's Republic of China.
| | - Chunshui Yu
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, 300052, People's Republic of China.
- School of Medical Imaging, Tianjin Medical University, Tianjin, 300052, People's Republic of China.
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16
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Lebrun F, Violle N, Letourneur A, Muller C, Fischer N, Levilly A, Orset C, Sors A, Vivien D. Post-acute delivery of α5-GABAA antagonist, S 44819, improves functional recovery in juvenile rats following stroke. Exp Neurol 2021; 347:113881. [PMID: 34597681 DOI: 10.1016/j.expneurol.2021.113881] [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: 04/19/2021] [Revised: 09/21/2021] [Accepted: 09/24/2021] [Indexed: 11/04/2022]
Abstract
Hypo-excitability was reported in the peri-infarct tissue following stroke, an effect counteracted by a blockage of α5-GABAA receptors in adult rodents. Our present study aims to evaluate the effect of a selective α5-GABAA receptor antagonist, S 44819, in stroke in juvenile animals. We have set up and characterized an original model of transient ischemic stroke in 28 day-old Sprague-Dawley rats (45-min occlusion of the middle cerebral artery by intraluminal suture). In this model, S 44819 (1, 3 and 10 mg/kg, b.i.d) was orally administered from day 3 to day 16 after stroke onset. Sensorimotor recovery was assessed on day 1, day 9 and day 16 after stroke onset. Results show that rats treated with S 44819 at the doses of 3 and 10 mg/kg displayed a significant improvement of the neurological deficits (neuroscore) on day 9 and day 16, when compared with animals treated with vehicle. Grip-test data analysis reveals that rats treated with S 44819 at the dose of 3 mg/kg displayed a better recovery on day 9 and day 16. These results are in agreement with those previously observed in adult rats, demonstrating that targeting α5-GABAA receptors improves neurological recovery after stroke in juvenile rats.
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Affiliation(s)
- Florent Lebrun
- ETAP-Lab, STROK@LLIANCE, 13 Rue du Bois de la Champelle, 54500 Vandoeuvre-les-Nancy, France; Normandie Univ, UNICAEN, INSERM, GIP Cyceron, Institut Blood and Brain @Caen-Normandie (BB@C), UMR-S U1237, Physiopathology and Imaging of Neurological Disorders (PhIND), Caen, France
| | - Nicolas Violle
- ETAP-Lab, STROK@LLIANCE, 13 Rue du Bois de la Champelle, 54500 Vandoeuvre-les-Nancy, France
| | - Annelise Letourneur
- ETAP-Lab, STROK@LLIANCE, 13 Rue du Bois de la Champelle, 54500 Vandoeuvre-les-Nancy, France
| | - Christophe Muller
- ETAP-Lab, STROK@LLIANCE, 13 Rue du Bois de la Champelle, 54500 Vandoeuvre-les-Nancy, France
| | - Nicolas Fischer
- ETAP-Lab, STROK@LLIANCE, 13 Rue du Bois de la Champelle, 54500 Vandoeuvre-les-Nancy, France
| | - Anthony Levilly
- ESRP (European Stroke Research Platform), Centre Universitaire de Ressources Biologiques (CURB), Université Caen Basse Normandie, Caen, France
| | - Cyrille Orset
- Normandie Univ, UNICAEN, INSERM, GIP Cyceron, Institut Blood and Brain @Caen-Normandie (BB@C), UMR-S U1237, Physiopathology and Imaging of Neurological Disorders (PhIND), Caen, France; ESRP (European Stroke Research Platform), Centre Universitaire de Ressources Biologiques (CURB), Université Caen Basse Normandie, Caen, France
| | - Aurore Sors
- Institut de Recherches Internationales Servier, Suresnes, France
| | - Denis Vivien
- Normandie Univ, UNICAEN, INSERM, GIP Cyceron, Institut Blood and Brain @Caen-Normandie (BB@C), UMR-S U1237, Physiopathology and Imaging of Neurological Disorders (PhIND), Caen, France; Department of Clinical Research, CHU Caen-Normandie, Caen, France.
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17
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Lamtahri R, Hazime M, Gowing EK, Nagaraja RY, Maucotel J, Alasoadura M, Quilichini PP, Lehongre K, Lefranc B, Gach-Janczak K, Marcher AB, Mandrup S, Vaudry D, Clarkson AN, Leprince J, Chuquet J. The Gliopeptide ODN, a Ligand for the Benzodiazepine Site of GABA A Receptors, Boosts Functional Recovery after Stroke. J Neurosci 2021; 41:7148-7159. [PMID: 34210784 PMCID: PMC8372017 DOI: 10.1523/jneurosci.2255-20.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 12/14/2020] [Accepted: 03/25/2021] [Indexed: 11/21/2022] Open
Abstract
Following stroke, the survival of neurons and their ability to reestablish connections is critical to functional recovery. This is strongly influenced by the balance between neuronal excitation and inhibition. In the acute phase of experimental stroke, lethal hyperexcitability can be attenuated by positive allosteric modulation of GABAA receptors (GABAARs). Conversely, in the late phase, negative allosteric modulation of GABAAR can correct the suboptimal excitability and improves both sensory and motor recovery. Here, we hypothesized that octadecaneuropeptide (ODN), an endogenous allosteric modulator of the GABAAR synthesized by astrocytes, influences the outcome of ischemic brain tissue and subsequent functional recovery. We show that ODN boosts the excitability of cortical neurons, which makes it deleterious in the acute phase of stroke. However, if delivered after day 3, ODN is safe and improves motor recovery over the following month in two different paradigms of experimental stroke in mice. Furthermore, we bring evidence that, during the subacute period after stroke, the repairing cortex can be treated with ODN by means of a single hydrogel deposit into the stroke cavity.SIGNIFICANCE STATEMENT Stroke remains a devastating clinical challenge because there is no efficient therapy to either minimize neuronal death with neuroprotective drugs or to enhance spontaneous recovery with neurorepair drugs. Around the brain damage, the peri-infarct cortex can be viewed as a reservoir of plasticity. However, the potential of wiring new circuits in these areas is restrained by a chronic excess of GABAergic inhibition. Here we show that an astrocyte-derived peptide, can be used as a delayed treatment, to safely correct cortical excitability and facilitate sensorimotor recovery after stroke.
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Affiliation(s)
- Rhita Lamtahri
- Normandie Université, UNIROUEN, Institut National de la Santé et de la Recherche Médicale U1239, Neuronal and Neuroendocrine Differentiation and Communication, Rouen, France
| | - Mahmoud Hazime
- Normandie Université, UNIROUEN, Institut National de la Santé et de la Recherche Médicale U1239, Neuronal and Neuroendocrine Differentiation and Communication, Rouen, France
| | - Emma K Gowing
- Department of Anatomy, Brain Health Research Centre and Brain Research New Zealand, University of Otago, Dunedin, 76000, 9054, New Zealand
| | - Raghavendra Y Nagaraja
- Department of Anatomy, Brain Health Research Centre and Brain Research New Zealand, University of Otago, Dunedin, 76000, 9054, New Zealand
| | - Julie Maucotel
- Normandie Université, UNIROUEN, Animal Facility, Rouen, 76000, France
| | - Michael Alasoadura
- Normandie Université, UNIROUEN, Institut National de la Santé et de la Recherche Médicale U1239, Neuronal and Neuroendocrine Differentiation and Communication, Rouen, France
| | | | - Katia Lehongre
- Inserm U 1127, Centre National de la Recherche Scientifique Unite Mixte de Recherche 7225, Sorbonne Universités, UPMC Univ Paris 06 Unite Mixte de Recherche S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, F-75013, France
| | - Benjamin Lefranc
- Normandie Université, UNIROUEN, Institut National de la Santé et de la Recherche Médicale U1239, Neuronal and Neuroendocrine Differentiation and Communication, Rouen, France
- Institute for Research and Innovation in Biomedicine, Normandie Université, PRIMACEN, Rouen, 76000, France
| | - Katarzyna Gach-Janczak
- Normandie Université, UNIROUEN, Institut National de la Santé et de la Recherche Médicale U1239, Neuronal and Neuroendocrine Differentiation and Communication, Rouen, France
- Department of Biomolecular Chemistry, Medicinal University of Łódź, Łódź, 90-137, Poland
| | - Ann-Britt Marcher
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, 5230, Denmark
| | - Susanne Mandrup
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, 5230, Denmark
| | - David Vaudry
- Normandie Université, UNIROUEN, Institut National de la Santé et de la Recherche Médicale U1239, Neuronal and Neuroendocrine Differentiation and Communication, Rouen, France
- Institute for Research and Innovation in Biomedicine, Normandie Université, PRIMACEN, Rouen, 76000, France
| | - Andrew N Clarkson
- Department of Anatomy, Brain Health Research Centre and Brain Research New Zealand, University of Otago, Dunedin, 76000, 9054, New Zealand
| | - Jérôme Leprince
- Normandie Université, UNIROUEN, Institut National de la Santé et de la Recherche Médicale U1239, Neuronal and Neuroendocrine Differentiation and Communication, Rouen, France
- Institute for Research and Innovation in Biomedicine, Normandie Université, PRIMACEN, Rouen, 76000, France
| | - Julien Chuquet
- Normandie Université, UNIROUEN, Institut National de la Santé et de la Recherche Médicale U1239, Neuronal and Neuroendocrine Differentiation and Communication, Rouen, France
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18
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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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19
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Mester JR, Bazzigaluppi P, Dorr A, Beckett T, Burke M, McLaurin J, Sled JG, Stefanovic B. Attenuation of tonic inhibition prevents chronic neurovascular impairments in a Thy1-ChR2 mouse model of repeated, mild traumatic brain injury. Am J Cancer Res 2021; 11:7685-7699. [PMID: 34335958 PMCID: PMC8315057 DOI: 10.7150/thno.60190] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 06/04/2021] [Indexed: 12/24/2022] Open
Abstract
Rationale: Mild traumatic brain injury (mTBI), the most common type of brain trauma, frequently leads to chronic cognitive and neurobehavioral deficits. Intervening effectively is impeded by our poor understanding of its pathophysiological sequelae. Methods: To elucidate the long-term neurovascular sequelae of mTBI, we combined optogenetics, two-photon fluorescence microscopy, and intracortical electrophysiological recordings in mice to selectively stimulate peri-contusional neurons weeks following repeated closed-head injury and probe individual vessel's function and local neuronal reactivity. Results: Compared to sham-operated animals, mTBI mice showed doubled cortical venular speeds (115 ± 25%) and strongly elevated cortical venular reactivity (53 ± 17%). Concomitantly, the pericontusional neurons exhibited attenuated spontaneous activity (-57 ± 79%) and decreased reactivity (-47 ± 28%). Post-mortem immunofluorescence revealed signs of peri-contusional senescence and DNA damage, in the absence of neuronal loss or gliosis. Alteration of neuronal and vascular functioning was largely prevented by chronic, low dose, systemic administration of a GABA-A receptor inverse agonist (L-655,708), commencing 3 days following the third impact. Conclusions: Our findings indicate that repeated mTBI leads to dramatic changes in the neurovascular unit function and that attenuation of tonic inhibition can prevent these alterations. The sustained disruption of the neurovascular function may underlie the concussed brain's long-term susceptibility to injury, and calls for development of better functional assays as well as of neurovascularly targeted interventions.
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20
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Inoue T, Takamatsu Y, Okamura M, Mani H, Hasegawa N, Maejima H. Specific inhibition of α5 subunit-containing GABA A receptors enhances locomotor activity and neuronal activity in the motor cortex. Biomed Res 2021; 42:103-108. [PMID: 34092751 DOI: 10.2220/biomedres.42.103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Gamma-aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the central nervous system (CNS). This study examined the effect of specific inhibition of α5 subunit-containing GABAA receptors (α5GABAAR) on the behavioral profile and neuronal activity of the CNS using a compound called L-655,708, which is a selective negative allosteric modulator of α5GABAAR. L-655,708 administration significantly increased locomotor activity without anxiety-related behavior. Furthermore, L-655,708 administration significantly increased c-Fos mRNA expression (a neuronal activity marker) in motor area of the cerebral cortex, whereas it hardly altered c-Fos mRNA expression in the sensory cortex, hippocampus, and spinal cord. This study revealed for the first time that alteration of neuronal activity with specific inhibition of α5GABAAR differs depending on each CNS region. α5GABAAR could be a potential target for modulating CNS excitability and behavioral activity.
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Affiliation(s)
- Takahiro Inoue
- Graduate School of Health Sciences, Hokkaido University.,Research Fellow of Japan Society for the Promotion of Science
| | - Yasuyuki Takamatsu
- Department of Rehabilitation Science, Faculty of Health Sciences, Hokkaido University
| | | | - Hiroki Mani
- Department of Rehabilitation Science, Faculty of Health Sciences, Hokkaido University
| | - Naoya Hasegawa
- Department of Rehabilitation Science, Faculty of Health Sciences, Hokkaido University
| | - Hiroshi Maejima
- Department of Rehabilitation Science, Faculty of Health Sciences, Hokkaido University
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21
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Wyroślak M, Lebida K, Mozrzymas JW. Induction of Inhibitory Synaptic Plasticity Enhances Tonic Current by Increasing the Content of α5-Subunit Containing GABA A Receptors in Hippocampal Pyramidal Neurons. Neuroscience 2021; 467:39-46. [PMID: 34033868 DOI: 10.1016/j.neuroscience.2021.05.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 05/14/2021] [Accepted: 05/17/2021] [Indexed: 11/16/2022]
Abstract
It is known that besides synaptic inhibition, there is a persistent component of inhibitory drive mediated by tonic currents which is believed to mediate majority of the total inhibitory charge in hippocampal neurons. Tonic currents, depending on cell types, can be mediated by a variety of GABAA receptor (GABAAR) subtypes but in pyramidal neurons, α5-subunit containing receptors were found to be predominant. Importantly, α5-GABAARs were implicated in both inhibitory and excitatory synaptic plasticity as well as in a variety of cognitive tasks. In the present study, we asked whether the protocol that evokes NMDAR-dependent GABAergic inhibitory long-term potentiation (iLTP) also induces the plasticity of tonic inhibition in hippocampal pyramidal neurons. Our whole-cell patch-clamp recordings revealed that the induction of this type of iLTP is associated with a marked increase in tonic current. By using the specific inverse agonist of α5-containing GABAARs (L-655,709) we provide evidence that this plastic change in tonic current is correlated with an increased proportion of this type of GABAARs. On the contrary, the iLTP induction did not affect the tonic current potentiated by THIP, indicating that the pool of δ subunit-containing GABAARs receptors remains unaffected. We conclude that the α5-GABAARs-dependent plasticity of tonic inhibition is a novel dimension of the neuroplasticity of the inhibitory drive in the hippocampal principal neurons. Overall, α5-containing GABAARs emerge as key players in a variety of plasticity mechanisms operating over a large span of time and spatial scales.
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Affiliation(s)
- Marcin Wyroślak
- Department of Biophysics and Neuroscience, Wroclaw Medical University, 50-367 Wroclaw, Poland.
| | - Katarzyna Lebida
- Department of Biophysics and Neuroscience, Wroclaw Medical University, 50-367 Wroclaw, Poland
| | - Jerzy W Mozrzymas
- Department of Biophysics and Neuroscience, Wroclaw Medical University, 50-367 Wroclaw, Poland
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22
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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.
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23
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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.
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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.
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24
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Petrache AL, Khan AA, Nicholson MW, Monaco A, Kuta-Siejkowska M, Haider S, Hilton S, Jovanovic JN, Ali AB. Selective Modulation of α5 GABA A Receptors Exacerbates Aberrant Inhibition at Key Hippocampal Neuronal Circuits in APP Mouse Model of Alzheimer's Disease. Front Cell Neurosci 2020; 14:568194. [PMID: 33262690 PMCID: PMC7686552 DOI: 10.3389/fncel.2020.568194] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 09/28/2020] [Indexed: 11/13/2022] Open
Abstract
Selective negative allosteric modulators (NAMs), targeting α5 subunit-containing GABAA receptors (GABAARs) as potential therapeutic targets for disorders associated with cognitive deficits, including Alzheimer's disease (AD), continually fail clinical trials. We investigated whether this was due to the change in the expression of α5 GABAARs, consequently altering synaptic function during AD pathogenesis. Using medicinal chemistry and computational modeling, we developed aqueous soluble hybrids of 6,6-dimethyl-3-(2-hydroxyethyl) thio-1-(thiazol-2-yl)-6,7-dihydro-2-benzothiophene-4(5H)-one, that demonstrated selective binding and high negative allosteric modulation, specifically for the α5 GABAAR subtypes in constructed HEK293 stable cell-lines. Using a knock-in mouse model of AD (APP NL-F/NL-F), which expresses a mutant form of human amyloid-β (Aβ), we performed immunofluorescence studies combined with electrophysiological whole-cell recordings to investigate the effects of our key molecule, α5-SOP002 in the hippocampal CA1 region. In aged APP NL-F/NL-F mice, selective preservation of α5 GABAARs was observed in, calretinin- (CR), cholecystokinin- (CCK), somatostatin- (SST) expressing interneurons, and pyramidal cells. Previously, we reported that CR dis-inhibitory interneurons, specialized in regulating other interneurons displayed abnormally high levels of synaptic inhibition in the APP NL-F/NL-F mouse model, here we show that this excessive inhibition was "normalized" to control values with bath-applied α5-SOP002 (1 μM). However, α5-SOP002, further impaired inhibition onto CCK and pyramidal cells that were already largely compromised by exhibiting a deficit of inhibition in the AD model. In summary, using a multi-disciplinary approach, we show that exposure to α5 GABAAR NAMs may further compromise aberrant synapses in AD. We, therefore, suggest that the α5 GABAAR is not a suitable therapeutic target for the treatment of AD or other cognitive deficits due to the widespread neuronal-networks that use α5 GABAARs.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Afia B Ali
- UCL School of Pharmacy, London, United Kingdom
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25
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He JW, Rabiller G, Nishijima Y, Akamatsu Y, Khateeb K, Yazdan-Shahmorad A, Liu J. Experimental cortical stroke induces aberrant increase of sharp-wave-associated ripples in the hippocampus and disrupts cortico-hippocampal communication. J Cereb Blood Flow Metab 2020; 40:1778-1796. [PMID: 31558106 PMCID: PMC7446570 DOI: 10.1177/0271678x19877889] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 07/22/2019] [Accepted: 07/25/2019] [Indexed: 11/16/2022]
Abstract
The functional consequences of ischemic stroke in the remote brain regions are not well characterized. The current study sought to determine changes in hippocampal oscillatory activity that may underlie the cognitive impairment observed following distal middle cerebral artery occlusion (dMCAO) without causing hippocampal structural damage. Local field potentials were recorded from the dorsal hippocampus and cortex in urethane-anesthetized rats with multichannel silicon probes during dMCAO and reperfusion, or mild ischemia induced by bilateral common carotid artery occlusion (CCAO). Bilateral change of brain state was evidenced by reduced theta/delta amplitude ratio and shortened high theta duration following acute dMCAO but not CCAO. An aberrant increase in the occurrence of sharp-wave-associated ripples (150-250 Hz), crucial for memory consolidation, was only detected after dMCAO reperfusion, coinciding with an increased occurrence of high-frequency discharges (250-450 Hz). dMCAO also significantly affected the modulation of gamma amplitude in the cortex coupled to hippocampal theta phase, although both hippocampal theta and gamma power were temporarily decreased during dMCAO. Our results suggest that MCAO may disrupt the balance between excitatory and inhibitory circuits in the hippocampus and alter the function of cortico-hippocampal network, providing a novel insight in how cortical stroke affects function in remote brain regions.
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Affiliation(s)
- Ji-Wei He
- Department of Neurological Surgery, UCSF, San Francisco, CA, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA, USA
| | - Gratianne Rabiller
- Department of Neurological Surgery, UCSF, San Francisco, CA, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA, USA
| | - Yasuo Nishijima
- Department of Neurological Surgery, UCSF, San Francisco, CA, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA, USA
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yosuke Akamatsu
- Department of Neurological Surgery, UCSF, San Francisco, CA, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA, USA
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Karam Khateeb
- Departments of Bioengineering and Electrical and Computer Engineering, University of Washington, Seattle, WA, USA
| | - Azadeh Yazdan-Shahmorad
- Departments of Bioengineering and Electrical and Computer Engineering, University of Washington, Seattle, WA, USA
- Center for Integrative Neuroscience and Department of Physiology, University of California, San Francisco, CA, USA
| | - Jialing Liu
- Department of Neurological Surgery, UCSF, San Francisco, CA, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA, USA
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26
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Tonon MC, Vaudry H, Chuquet J, Guillebaud F, Fan J, Masmoudi-Kouki O, Vaudry D, Lanfray D, Morin F, Prevot V, Papadopoulos V, Troadec JD, Leprince J. Endozepines and their receptors: Structure, functions and pathophysiological significance. Pharmacol Ther 2020; 208:107386. [DOI: 10.1016/j.pharmthera.2019.06.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 06/20/2019] [Indexed: 02/06/2023]
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27
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Khodaei S, Avramescu S, Wang DS, Sheng H, Chan NK, Lecker I, Fernandez-Escobar A, Lei G, Dewar MB, Whissell PD, Baker AJ, Orser BA. Inhibiting α5 Subunit-Containing γ-Aminobutyric Acid Type A Receptors Attenuates Cognitive Deficits After Traumatic Brain Injury. Crit Care Med 2020; 48:533-544. [PMID: 32205600 DOI: 10.1097/ccm.0000000000004161] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVES Cognitive deficits after traumatic brain injury are a leading cause of disability worldwide, yet no effective pharmacologic treatments exist to improve cognition. Traumatic brain injury increases proinflammatory cytokines, which trigger excess function of α5 subunit-containing γ-aminobutyric acid type A receptors. In several models of brain injury, drugs that inhibit α5 subunit-containing γ-aminobutyric acid type A receptor function improve cognitive performance. Thus, we postulated that inhibiting α5 subunit-containing γ-aminobutyric acid type A receptors would improve cognitive performance after traumatic brain injury. In addition, because traumatic brain injury reduces long-term potentiation in the hippocampus, a cellular correlate of memory, we studied whether inhibition of α5 subunit-containing γ-aminobutyric acid type A receptors attenuated deficits in long-term potentiation after traumatic brain injury. DESIGN Experimental animal study. SETTING Research laboratory. SUBJECTS Adult male mice and hippocampal brain slices. INTERVENTIONS Anesthetized mice were subjected to traumatic brain injury with a closed-head, free-weight drop method. One week later, the mice were treated with L-655,708 (0.5 mg/kg), an inhibitor that is selective for α5 subunit-containing γ-aminobutyric acid type A receptors, 30 minutes before undergoing behavioral testing. Problem-solving abilities were assessed using the puzzle box assay, and memory performance was studied with novel object recognition and object place recognition assays. In addition, hippocampal slices were prepared 1 week after traumatic brain injury, and long-term potentiation was studied using field recordings in the cornu Ammonis 1 region of slices that were perfused with L-655,708 (100 nM). MEASUREMENTS AND MAIN RESULTS Traumatic brain injury increased the time required to solve difficult but not simple tasks in the puzzle box assay and impaired memory in the novel object recognition and object place recognition assays. L-655,708 improved both problem solving and memory in the traumatic brain injury mice. Traumatic brain injury reduced long-term potentiation in the hippocampal slices, and L-655,708 attenuated this reduction. CONCLUSIONS Pharmacologic inhibition of α5 subunit-containing γ-aminobutyric acid type A receptors attenuated cognitive deficits after traumatic brain injury and enhanced synaptic plasticity in hippocampal slices. Collectively, these results suggest that α5 subunit-containing γ-aminobutyric acid type A receptors are novel targets for pharmacologic treatment of traumatic brain injury-induced persistent cognitive deficits.
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Affiliation(s)
- Shahin Khodaei
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Sinziana Avramescu
- Department of Anesthesia, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Dian-Shi Wang
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Heping Sheng
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Nathan K Chan
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Irene Lecker
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | | | - Gang Lei
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Michael B Dewar
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Paul D Whissell
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Andrew J Baker
- Department of Anesthesia, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia, St. Michael's Hospital, Toronto, ON, Canada
| | - Beverley A Orser
- Department of Physiology, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
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Koh MT, Branch A, Haberman R, Gallagher M. Significance of inhibitory recruitment in aging with preserved cognition: limiting gamma-aminobutyric acid type A α5 function produces memory impairment. Neurobiol Aging 2020; 91:1-4. [PMID: 32240868 DOI: 10.1016/j.neurobiolaging.2020.02.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 12/30/2019] [Accepted: 02/22/2020] [Indexed: 01/27/2023]
Abstract
Numerous aging studies have identified a shift in the excitatory/inhibitory (E/I) balance with heightened hippocampal neural activity associated with age-related memory impairment across species, including rats, monkeys, and humans. Neurobiological investigations directed at the hippocampal formation have demonstrated that unimpaired aged rats performing on par with young adult rats in a spatial memory task exhibit gene expression profiles, mechanisms for plasticity, and altered circuit/network function, which are distinct from younger rats. Particularly striking is a convergence of observational evidence that aged unimpaired rats augment recruitment of mechanisms associated with neural inhibition, a finding that may represent an adaptive homeostatic adjustment necessary to maintain neural plasticity and memory function in aging. In this study, we test the effect of limiting inhibition via administration of TB21007, a negative allosteric modulator of the alpha 5 subtype of gamma-aminobutyric acid type A α5 receptor, on a radial arm maze assessment of memory function. Impaired memory performance produced by this intervention in otherwise high-performing aged rats supports an adaptive role for gamma-aminobutyric acid in the functional maintenance of intact cognition in aging.
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Affiliation(s)
- Ming Teng Koh
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Audrey Branch
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Rebecca Haberman
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA.
| | - Michela Gallagher
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
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Paine TA, Chang S, Poyle R. Contribution of GABA A receptor subunits to attention and social behavior. Behav Brain Res 2020; 378:112261. [PMID: 31560920 DOI: 10.1016/j.bbr.2019.112261] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 09/23/2019] [Accepted: 09/23/2019] [Indexed: 12/28/2022]
Abstract
INTRODUCTION GABA dysfunction is associated with a number of psychiatric conditions including schizophrenia, autism and depression. Blocking cortical GABAA receptors in rodents causes behavioral deficits, including impaired attention and sociability, that are consistent with the symptoms of these conditions. The subunit composition of GABAA receptors is diverse and can affect receptor function. The current experiment examined the role of GABAA receptors containing different α-subunits in social behavior and attention. METHODS Male Sprague-Dawley rats were administered FG7142 (0.0-5.0 mg/kg; a non-selective GABAA receptor inverse agonist), L-655,708 (0-1.0 mg/kg; a low efficacy inverse agonist at α5-containing GABAA receptors), MRK-016 (0.0-2.0 mg/kg; a high efficacy inverse agonist at α5-containing GABAA receptors), or L-838,417 (0.0-3.0 mg/kg; an antagonist at α1-containing receptors and a partial agonist at α2, α3, α5-containing GABAA receptors) and either tested on the social interaction and social preference tests or the 5-choice serial reaction time task. RESULTS FG7142 decreased social interactions and impaired attention. MRK-016 impaired attention but did not affect social behavior. Neither L-655,708 nor L-838,417 significantly affected either social behavior or attention. DISCUSSION Systemic reduction in GABAA receptor signaling decreased sociability and attention, a result consistent with past research demonstrating cortical GABAA receptor blockade impairs social behavior and attention. Overall, the effects of the receptor subtype selective ligands were minimal; α5-containing GABAA receptors may contribute to the attentional deficit but do not contribute to the decrease in sociability. Further research is needed to determine the GABAA receptor subunits that contribute to social behavior and attention.
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Affiliation(s)
- Tracie A Paine
- Department of Neuroscience, Oberlin College, Oberlin, OH, 44074, United States.
| | - Sara Chang
- Department of Neuroscience, Oberlin College, Oberlin, OH, 44074, United States
| | - Rachel Poyle
- Department of Neuroscience, Oberlin College, Oberlin, OH, 44074, United States
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Gao T, Liu Y, Zhao Z, Luo Y, Wang L, Wang Y, Yin Y. L-655,708 Does not Prevent Isoflurane-induced Memory Deficits in Old Mice. Transl Neurosci 2019; 10:180-186. [PMID: 31410301 PMCID: PMC6689210 DOI: 10.1515/tnsci-2019-0032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 06/21/2019] [Indexed: 01/07/2023] Open
Abstract
Background General anesthesia and increasing age are two main risk factors for postoperative cognitive dysfunction (POCD). Effective agents for the prevention or treatment of POCD are urgently needed. L-655,708, an inverse agonist of α5 subunit-containing γ-aminobutyric acid subtype A (α5GABAA) receptors, can prevent anesthesia-induced memory deficits in young animals. However, there is a lack of evidence of its efficacy in old animals. Methodology Young (3- to 5-month-old) and old (18- to 20-month-old) mice were given an inhalation of 1.33% isoflurane for 1 hour and their associative memory was evaluated 24 hours after anesthesia using fear-conditioning tests (FCTs). To evaluate the effect of L-655,708, mice received intraperitoneal injections of L-655,708 (0.7 mg/kg) or vehicle 30 minutes before anesthesia. Results Old mice exhibited impaired memory and lower hippocampal α5GABAA levels than young mice under physiological conditions. Pre-injections of L-655,708 significantly alleviated isoflurane-induced memory decline in young mice, but not in old mice. Conclusions L-655,708 is not as effective for the prevention of POCD in old mice as it is in young mice. The use of inverse agonists of α5GABAA in preventing POCD in old patients should be carefully considered.
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Affiliation(s)
- Teng Gao
- Department of Anesthesiology, Beijing Shijitan Hospital, Capital Medical University, Beijing, 100038, China
| | - Yue Liu
- Department of Anesthesiology, China-Japan Friendship Hospital, Beijing, 100029, China
| | - Zifang Zhao
- Department of Anesthesiology, China-Japan Friendship Hospital, Beijing, 100029, China
| | - Yuan Luo
- State Key Laboratory of Toxicology and Medical Countermeasures, Academy of Military Medical Sciences, Beijing, 100850, China
| | - Lifang Wang
- Department of Anesthesiology, China-Japan Friendship Hospital, Beijing, 100029, China
| | - Yongan Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, Academy of Military Medical Sciences, Beijing, 100850, China
| | - Yiqing Yin
- Department of Anesthesiology, China-Japan Friendship Hospital, Beijing, 100029, China
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31
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Jacob TC. Neurobiology and Therapeutic Potential of α5-GABA Type A Receptors. Front Mol Neurosci 2019; 12:179. [PMID: 31396049 PMCID: PMC6668551 DOI: 10.3389/fnmol.2019.00179] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 07/08/2019] [Indexed: 01/11/2023] Open
Abstract
α5 subunit containing GABA type A receptors (GABAARs) have long been an enigmatic receptor subtype of interest due to their specific brain distribution, unusual surface localization and key role in synaptic plasticity, cognition and memory. These receptors are uniquely positioned to sculpt both the developing and mature hippocampal circuitry due to high overall expression and a distinct peak within the critical synapse formation period during the second postnatal week. Unlike the majority of other GABAARs, they exhibit both receptor clustering at extrasynaptic sites via interactions with the radixin scaffold as well as synaptic sites via gephyrin, thus contributing respectively to tonic currents and synaptic GABAergic neurotransmission. α5 GABAAR signaling can be altered in neurodevelopmental disorders including autism and mental retardation and by inflammation in CNS injury and disease. Due to the unique physiology and pharmacology of α5 GABAARs, drugs targeting these receptors are being developed and tested as treatments for neurodevelopmental disorders, depression, schizophrenia, and mild cognitive impairment. This review article focuses on advances in understanding how the α5 subunit contributes to GABAAR neurobiology. In particular, I discuss both recent insights and remaining knowledge gaps for the functional role of these receptors, pathologies associated with α5 GABAAR dysfunction, and the effects and potential therapeutic uses of α5 receptor subtype targeted drugs.
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Affiliation(s)
- Tija C Jacob
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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32
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Belinskaia DA, Belinskaia MA, Barygin OI, Vanchakova NP, Shestakova NN. Psychotropic Drugs for the Management of Chronic Pain and Itch. Pharmaceuticals (Basel) 2019; 12:ph12020099. [PMID: 31238561 PMCID: PMC6631469 DOI: 10.3390/ph12020099] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 06/19/2019] [Accepted: 06/21/2019] [Indexed: 12/11/2022] Open
Abstract
Clinical observations have shown that patients with chronic neuropathic pain or itch exhibit symptoms of increased anxiety, depression and cognitive impairment. Such patients need corrective therapy with antidepressants, antipsychotics or anticonvulsants. It is known that some psychotropic drugs are also effective for the treatment of neuropathic pain and pruritus syndromes due to interaction with the secondary molecular targets. Our own clinical studies have identified antipruritic and/or analgesic efficacy of the following compounds: tianeptine (atypical tricyclic antidepressant), citalopram (selective serotonin reuptake inhibitor), mianserin (tetracyclic antidepressant), carbamazepine (anticonvulsant), trazodone (serotonin antagonist and reuptake inhibitor), and chlorprothixene (antipsychotic). Venlafaxine (serotonin-norepinephrine reuptake inhibitor) is known to have an analgesic effect too. The mechanism of such effect of these drugs is not fully understood. Herein we review and correlate the literature data on analgesic/antipruritic activity with pharmacological profile of these compounds.
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Affiliation(s)
- Daria A Belinskaia
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia.
| | - Mariia A Belinskaia
- International Centre for Neurotherapeutics, Dublin City University, Glasnevin, Dublin 9, Ireland.
| | - Oleg I Barygin
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia.
| | - Nina P Vanchakova
- Department of Pedagogy and Psychology, Faculty of Postgraduate Education, First Pavlov State Medical University, L'va Tolstogo str. 6-8, St. Petersburg 197022, Russia.
| | - Natalia N Shestakova
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia.
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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.
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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;
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Orfila JE, Grewal H, Dietz RM, Strnad F, Shimizu T, Moreno M, Schroeder C, Yonchek J, Rodgers KM, Dingman A, Bernard TJ, Quillinan N, Macklin WB, Traystman RJ, Herson PS. Delayed inhibition of tonic inhibition enhances functional recovery following experimental ischemic stroke. J Cereb Blood Flow Metab 2019; 39:1005-1014. [PMID: 29283314 PMCID: PMC6547193 DOI: 10.1177/0271678x17750761] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The current study focuses on the ability to improve cognitive function after stroke with interventions administered at delayed/chronic time points. In light of recent studies demonstrating delayed GABA antagonists improve motor function, we utilized electrophysiology, biochemistry and neurobehavioral methods to investigate the role of α5 GABAA receptors on hippocampal plasticity and functional recovery following ischemic stroke. Male C57Bl/6 mice were exposed to 45 min transient middle cerebral artery occlusion and analysis of synaptic and functional deficits performed 7 or 30 days after recovery. Our findings indicate that hippocampal long-term potentiation (LTP) is impaired 7 days after stroke and remain impaired for at least 30 days. We demonstrate that ex vivo administration of L655,708 reversed ischemia-induced plasticity deficits and importantly, in vivo administration at delayed time-points reversed stroke-induced memory deficits. Western blot analysis of hippocampal tissue reveals proteins responsible for GABA synthesis are upregulated (GAD65/67 and MAOB), increasing GABA in hippocampal interneurons 30 days after stroke. Thus, our data indicate that both synaptic plasticity and memory impairments observed after stroke are caused by excessive tonic GABA activity, making inhibition of specific GABA activity at delayed timepoints a potential therapeutic approach to improve functional recovery and reverse cognitive impairments after stroke.
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Affiliation(s)
- James E Orfila
- 1 Department of Anesthesiology, University of Colorado, Aurora, CO, USA.,2 Neuronal Injury Program, University of Colorado, Aurora, CO, USA
| | - Himmat Grewal
- 1 Department of Anesthesiology, University of Colorado, Aurora, CO, USA.,2 Neuronal Injury Program, University of Colorado, Aurora, CO, USA
| | - Robert M Dietz
- 2 Neuronal Injury Program, University of Colorado, Aurora, CO, USA.,3 Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | - Frank Strnad
- 1 Department of Anesthesiology, University of Colorado, Aurora, CO, USA.,2 Neuronal Injury Program, University of Colorado, Aurora, CO, USA
| | - Takeru Shimizu
- 1 Department of Anesthesiology, University of Colorado, Aurora, CO, USA.,2 Neuronal Injury Program, University of Colorado, Aurora, CO, USA
| | - Myriam Moreno
- 1 Department of Anesthesiology, University of Colorado, Aurora, CO, USA.,2 Neuronal Injury Program, University of Colorado, Aurora, CO, USA
| | - Christian Schroeder
- 1 Department of Anesthesiology, University of Colorado, Aurora, CO, USA.,2 Neuronal Injury Program, University of Colorado, Aurora, CO, USA
| | - Joan Yonchek
- 1 Department of Anesthesiology, University of Colorado, Aurora, CO, USA
| | - Krista M Rodgers
- 1 Department of Anesthesiology, University of Colorado, Aurora, CO, USA
| | - Andra Dingman
- 3 Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | | | - Nidia Quillinan
- 1 Department of Anesthesiology, University of Colorado, Aurora, CO, USA.,2 Neuronal Injury Program, University of Colorado, Aurora, CO, USA
| | - Wendy B Macklin
- 4 Department of Cell and Developmental Biology, University of Colorado, Aurora, CO, USA
| | - Richard J Traystman
- 1 Department of Anesthesiology, University of Colorado, Aurora, CO, USA.,2 Neuronal Injury Program, University of Colorado, Aurora, CO, USA.,5 Department of Pharmacology, School of Medicine, University of Colorado, Aurora, CO, USA
| | - Paco S Herson
- 1 Department of Anesthesiology, University of Colorado, Aurora, CO, USA.,2 Neuronal Injury Program, University of Colorado, Aurora, CO, USA.,5 Department of Pharmacology, School of Medicine, University of Colorado, Aurora, CO, USA
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Chen X, van Gerven J, Cohen A, Jacobs G. Human pharmacology of positive GABA-A subtype-selective receptor modulators for the treatment of anxiety. Acta Pharmacol Sin 2019; 40:571-582. [PMID: 30518829 DOI: 10.1038/s41401-018-0185-5] [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] [Received: 03/25/2018] [Accepted: 10/10/2018] [Indexed: 12/11/2022] Open
Abstract
Anxiety disorders arise from disruptions among the highly interconnected circuits that normally serve to process the streams of potentially threatening stimuli. The resulting imbalance among these circuits can cause a fundamental misinterpretation of neural sensory information as threatening and can lead to the inappropriate emotional and behavioral responses observed in anxiety disorders. There is considerable preclinical evidence that the GABAergic system, in general, and its α2- and/or α5-subunit-containing GABA(A) receptor subtypes, in particular, are involved in the pathophysiology of anxiety disorders. However, the clinical efficacy of GABA-A α2-selective agonists for the treatment of anxiety disorders has not been unequivocally demonstrated. In this review, we present several human pharmacological studies that have been performed with the aim of identifying the pharmacologically active doses/exposure levels of several GABA-A subtype-selective novel compounds with potential anxiolytic effects. The pharmacological selectivity of novel α2-subtype-selective GABA(A) receptor partial agonists has been demonstrated by their distinct effect profiles on the neurophysiological and neuropsychological measurements that reflect the functions of multiple CNS domains compared with those of benzodiazepines, which are nonselective, full GABA(A) agonists. Normalizing the undesired pharmacodynamic side effects against the desired on-target effects on the saccadic peak velocity is a useful approach for presenting the pharmacological features of GABA(A)-ergic modulators. Moreover, combining the anxiogenic symptom provocation paradigm with validated neurophysiological and neuropsychological biomarkers may provide further construct validity for the clinical effects of novel anxiolytic agents. In addition, the observed drug effects on serum prolactin levels support the use of serum prolactin levels as a complementary neuroendocrine biomarker to further validate the pharmacodynamic measurements used during the clinical pharmacological study of novel anxiolytic agents.
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Delayed treatment of α5 GABAA receptor inverse agonist improves functional recovery by enhancing neurogenesis after cerebral ischemia-reperfusion injury in rat MCAO model. Sci Rep 2019; 9:2287. [PMID: 30783142 PMCID: PMC6381084 DOI: 10.1038/s41598-019-38750-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 12/18/2018] [Indexed: 11/08/2022] Open
Abstract
Development of effective therapeutics and treatment strategy to promote recovery after cerebral ischemia-reperfusion injury necessitates further understandings of the complex pathophysiology of ischemic stroke. Given that α5-GABAAR inhibition has been shown to be involved in functional recovery after stroke, the present study was designed to evaluate the effects of treatment timing of α5 GABAAR inhibition on post-middle cerebral artery occlusion (MCAO) functional recovery. To this end, we examined the effects of L655,708 (α5 GABAAR inverse agonist) treatment at 3 or 7 days post-ischemia on apoptosis and neurogenesis in the peri-infarct region, brain infarction size, as well as modified neurological severity score (mNSS) and rotarod test time in rats. Consistent with previous reports, we found that when the treatment of L655,708 was initiated at post-MCAO day 3, it did not alter the functional recovery in rats. However, when the treatment of L655,708 was initiated at post-MCAO day 7, it demonstrated beneficial effects on functional recovery in rats. Interestingly, this phenomenon was not associated with altered brain infarction size nor with changes in brain cell apoptosis. However, we found that delayed treatment of L655,708 at post-MCAO day 7 significantly increased neurogenesis in peri-infarct zone in rats. These results suggested that removing α5 GABAAR-mediated tonic inhibition after cerebral ischemia-reperfusion injury may be an effective therapeutic strategy for promoting functional recovery from stroke.
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van Amerongen G, Siebenga PS, Gurrell R, Dua P, Whitlock M, Gorman D, Okkerse P, Hay JL, Butt RP, Groeneveld GJ. Analgesic potential of PF-06372865, an α2/α3/α5 subtype-selective GABA A partial agonist, in humans. Br J Anaesth 2019; 123:e194-e203. [PMID: 30915991 DOI: 10.1016/j.bja.2018.12.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 12/11/2018] [Accepted: 12/11/2018] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND This study investigated the analgesic effects of two doses (15 and 65 mg) of PF-06372865, a novel α2/α3/α5 gamma-aminobutyric acid A (GABAA) subunit selective partial positive allosteric modulator (PAM), compared with placebo and pregabalin (300 mg) as a positive control. METHODS We performed a randomised placebo-controlled crossover study (NCT02238717) in 20 healthy subjects, using a battery of pain tasks (electrical, pressure, heat, cold and inflammatory pain, including a paradigm of conditioned pain modulation). Pharmacodynamic measurements were performed at baseline and up to 10 h after dose. RESULTS A dose of 15 mg PF-06372865 increased pain tolerance thresholds (PTTs) for pressure pain at a ratio of 1.11 (90% confidence interval [CI]: 1.02, 1.22) compared with placebo. A dose of 65 mg PF-06372865 led to an increase in PTT for the cold pressor at a ratio of 1.17 (90% CI: 1.03, 1.32), and pressure pain task: 1.11 (90% CI: 1.01, 1.21). Pregabalin showed an increase in PTT for pressure pain at a ratio of 1.15 (95% CI: 1.06, 1.26) and cold pressor task: 1.31 (90% CI: 1.16, 1.48). CONCLUSION We conclude that PF-06372865 has analgesic potential at doses that do not induce significant sedation or other intolerable adverse events limiting its clinical use. In addition, the present study established the potential role for this battery of pain tasks as a tool in the development of analgesics with a novel mechanism of action, for the treatment of various pain states including neuropathic pain and to establish proof-of-concept. CLINICAL TRIALS REGISTRATION NCT0223871.
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Affiliation(s)
| | | | | | - Pinky Dua
- Early Clinical Development, Pfizer WRD, Cambridge, UK
| | - Mark Whitlock
- Early Clinical Development, Pfizer WRD, Cambridge, UK
| | - Donal Gorman
- Early Clinical Development, Pfizer WRD, Cambridge, UK
| | - Pieter Okkerse
- Centre for Human Drug Research (CHDR), Leiden, the Netherlands
| | - Justin L Hay
- Centre for Human Drug Research (CHDR), Leiden, the Netherlands
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Branch A, Monasterio A, Blair G, Knierim JJ, Gallagher M, Haberman RP. Aged rats with preserved memory dynamically recruit hippocampal inhibition in a local/global cue mismatch environment. Neurobiol Aging 2019; 76:151-161. [PMID: 30716540 DOI: 10.1016/j.neurobiolaging.2018.12.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 12/14/2018] [Accepted: 12/27/2018] [Indexed: 10/27/2022]
Abstract
Similar to elderly humans, aged outbred Long-Evans rats exhibit individual differences in memory abilities, including a subset of aged rats that maintain memory function on par with young adults. Such individuals provide a basis for investigating mechanisms of resilience to age-related decline. The present study examined hippocampal gene expression in young adults and aged rats with preserved memory function under behavioral task conditions well established for assessing information processing central to the formation of episodic memory. Although behavioral measures and hippocampal gene induction associated with neural activity and synaptic plasticity were similar across age groups, a marker for inhibitory interneuron function in the hippocampal formation was distinctively increased only in aged rats but not in young adults. Because heightened hippocampal neural activity is associated with age-related memory impairment across species, including rats, monkeys, and humans, this finding may represent an adaptive homeostatic adjustment necessary to maintain neural plasticity and memory function in aging.
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Affiliation(s)
- Audrey Branch
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Amy Monasterio
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Grace Blair
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - James J Knierim
- Department of Neuroscience and Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Michela Gallagher
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Rebecca P Haberman
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA.
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Input-Specific Synaptic Location and Function of the α5 GABA A Receptor Subunit in the Mouse CA1 Hippocampal Neurons. J Neurosci 2018; 39:788-801. [PMID: 30523065 DOI: 10.1523/jneurosci.0567-18.2018] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 10/01/2018] [Accepted: 10/30/2018] [Indexed: 12/21/2022] Open
Abstract
Hippocampus-dependent learning processes are coordinated via a large diversity of GABAergic inhibitory mechanisms. The α5 subunit-containing GABAA receptor (α5-GABAAR) is abundantly expressed in the hippocampus populating primarily the extrasynaptic domain of CA1 pyramidal cells, where it mediates tonic inhibitory conductance and may cause functional deficits in synaptic plasticity and hippocampus-dependent memory. However, little is known about synaptic expression of the α5-GABAAR and, accordingly, its location site-specific function. We examined the cell- and synapse-specific distribution of the α5-GABAAR in the CA1 stratum oriens/alveus (O/A) using a combination of immunohistochemistry, whole-cell patch-clamp recordings and optogenetic stimulation in hippocampal slices obtained from mice of either sex. In addition, the input-specific role of the α5-GABAAR in spatial learning and anxiety-related behavior was studied using behavioral testing and chemogenetic manipulations. We demonstrate that α5-GABAAR is preferentially targeted to the inhibitory synapses made by the vasoactive intestinal peptide (VIP)- and calretinin-positive terminals onto dendrites of somatostatin-expressing interneurons. In contrast, synapses made by the parvalbumin-positive inhibitory inputs to O/A interneurons showed no or little α5-GABAAR. Inhibiting the α5-GABAAR in control mice in vivo improved spatial learning but also induced anxiety-like behavior. Inhibiting the α5-GABAAR in mice with inactivated CA1 VIP input could still improve spatial learning and was not associated with anxiety. Together, these data indicate that the α5-GABAAR-mediated phasic inhibition via VIP input to interneurons plays a predominant role in the regulation of anxiety while the α5-GABAAR tonic inhibition via this subunit may control spatial learning.SIGNIFICANCE STATEMENT The α5-GABAAR subunit exhibits high expression in the hippocampus, and regulates the induction of synaptic plasticity and the hippocampus-dependent mnemonic processes. In CA1 principal cells, this subunit occupies mostly extrasynaptic sites and mediates tonic inhibition. Here, we provide evidence that, in CA1 somatostatin-expressing interneurons, the α5-GABAAR subunit is targeted to synapses formed by the VIP- and calretinin-expressing inputs, and plays a specific role in the regulation of anxiety-like behavior.
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40
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Enhanced GABAergic Tonic Inhibition Reduces Intrinsic Excitability of Hippocampal CA1 Pyramidal Cells in Experimental Autoimmune Encephalomyelitis. Neuroscience 2018; 395:89-100. [PMID: 30447391 DOI: 10.1016/j.neuroscience.2018.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 11/03/2018] [Accepted: 11/05/2018] [Indexed: 11/24/2022]
Abstract
Cognitive impairment (CI), a debilitating and pervasive feature of multiple sclerosis (MS), is correlated with hippocampal atrophy. Findings from postmortem MS hippocampi indicate that expression of genes involved in both excitatory and inhibitory neurotransmission are altered in MS, and although deficits in excitatory neurotransmission have been reported in the MS model experimental autoimmune encephalomyelitis (EAE), the functional consequence of altered inhibitory neurotransmission remains poorly understood. In this study, we used electrophysiological and biochemical techniques to examine inhibitory neurotransmission in the CA1 region of the hippocampus in EAE. We find that tonic, GABAergic inhibition is enhanced in CA1 pyramidal cells from EAE mice. Although plasma membrane expression of the GABA transporter GAT-3 was decreased in the EAE hippocampus, an increased surface expression of α5 subunit-containing GABAA receptors appears to be primarily responsible for the increase in tonic inhibition during EAE. Enhanced tonic inhibition during EAE was associated with decreased CA1 pyramidal cell excitability and inhibition of α5 subunit-containing GABAA receptors with the negative allosteric modulator L-655,708 enhanced pyramidal cell excitability in EAE mice. Together, our results suggest that altered GABAergic neurotransmission may underlie deficits in hippocampus-dependent cognitive function in EAE and MS.
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Xiong Z, Zhang K, Ishima T, Ren Q, Chang L, Chen J, Hashimoto K. Comparison of rapid and long-lasting antidepressant effects of negative modulators of α5-containing GABA A receptors and (R)‑ketamine in a chronic social defeat stress model. Pharmacol Biochem Behav 2018; 175:139-145. [PMID: 30359627 DOI: 10.1016/j.pbb.2018.10.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 10/21/2018] [Accepted: 10/21/2018] [Indexed: 12/18/2022]
Abstract
The negative allosteric modulators (NAMs: L-655,708 and MRK-016) of α5 subunit-containing GABAA receptors are reported to show rapid-acting antidepressant effects in rodents. However, there are no reports comparing these NAMs and (R)‑ketamine, (R)-enantiomer of the rapid-acting antidepressant ketamine, in a chronic social defeat stress (CSDS) model. Here we measured expression of α5 GABAA receptor in the brain regions from CSDS susceptible mice and postmortem brain samples from depressed patients. Expression of α5 GABAA receptor in the prefrontal cortex and hippocampus from CSDS susceptible mice was significantly higher than that of control mice. Furthermore, expression of α5 GABAA receptor in the parietal cortex from depressed patients was also higher than that of control subjects. In the tail suspension and forced swimming tests, (R)‑ketamine and MRK-016 significantly attenuated the increased immobility time in the susceptible mice, compared with the vehicle-treated group. In the sucrose preference test, (R)‑ketamine and MRK-016 significantly enhanced the reduced preference in CSDS susceptible mice two days after a single injection. Unlike (R)‑ketamine, MRK-016 did not attenuate the reduced sucrose preference in susceptible mice 7 days after a single injection. In contrast, L-655,708 did not show antidepressant effects in the same model. In conclusion, this study shows that increased levels of α5 GABAA receptors in the PFC and hippocampus may play a role in depression-like phenotype after CSDS. It is unlikely that MRK-016 has long-lasting antidepressant effects although it elicits rapid-acting antidepressant effects.
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Affiliation(s)
- Zhongwei Xiong
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba 260-8670, Japan; Department of Neurosurgery, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan 430071, PR China
| | - Kai Zhang
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba 260-8670, Japan
| | - Tamaki Ishima
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba 260-8670, Japan
| | - Qian Ren
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba 260-8670, Japan
| | - Lijia Chang
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba 260-8670, Japan
| | - Jincao Chen
- Department of Neurosurgery, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan 430071, PR China
| | - Kenji Hashimoto
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba 260-8670, Japan.
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42
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Sieghart W, Savić MM. International Union of Basic and Clinical Pharmacology. CVI: GABAA Receptor Subtype- and Function-selective Ligands: Key Issues in Translation to Humans. Pharmacol Rev 2018; 70:836-878. [DOI: 10.1124/pr.117.014449] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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43
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Szodorai E, Bampali K, Romanov RA, Kasper S, Hökfelt T, Ernst M, Lubec G, Harkany T. Diversity matters: combinatorial information coding by GABA A receptor subunits during spatial learning and its allosteric modulation. Cell Signal 2018; 50:142-159. [DOI: 10.1016/j.cellsig.2018.07.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 07/08/2018] [Accepted: 07/09/2018] [Indexed: 01/11/2023]
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44
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The Benzodiazepine Binding Sites of GABAA Receptors. Trends Pharmacol Sci 2018; 39:659-671. [DOI: 10.1016/j.tips.2018.03.006] [Citation(s) in RCA: 107] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 03/15/2018] [Accepted: 03/22/2018] [Indexed: 11/24/2022]
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45
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Jiang Y, Xiao Y, Zhang X, Shu Y. Activation of axon initial segmental GABA A receptors inhibits action potential generation in neocortical GABAergic interneurons. Neuropharmacology 2018; 138:97-105. [PMID: 29883765 DOI: 10.1016/j.neuropharm.2018.05.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Revised: 05/14/2018] [Accepted: 05/20/2018] [Indexed: 10/16/2022]
Abstract
Ionotropic GABAA receptors expressing at the axon initial segment (AIS) of glutamatergic pyramidal cell (PC) in the cortex plays critical roles in regulating action potential generation. However, it remains unclear whether these receptors also express at the AIS of cortical GABAergic interneurons. In mouse prefrontal cortical slices, we performed experiments at the soma and AIS of the two most abundant GABAergic interneurons: parvalbumin (PV) and somatostatin (SST) positive neurons. Local application of GABA at the perisomatic axonal regions could evoke picrotoxin-sensitive currents with a reversal potential near the Cl- equilibrium potential. Puffing agonists to outside-out patches excised from AIS confirmed the expression of GABAA receptors. Further pharmacological experiments revealed that GABAA receptors in AIS of PV neurons contain α1 subunits, different from those containing α2/3 in AIS and α4 in axon trunk of layer-5 PCs. Cell-attached recording at the soma of PV and SST neurons revealed that the activation of AIS GABAA receptors inhibits the action potential generation induced by synaptic stimulation. Together, our results demonstrate that the AIS of PV and SST neurons express GABAA receptors with distinct subunit composition, which exert an inhibitory effect on neuronal excitability in these inhibitory interneurons.
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Affiliation(s)
- Yanbo Jiang
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Yujie Xiao
- State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, School of Brain and Cognitive Sciences, Beijing Normal University, Beijing 100875, China
| | - Xiaoxue Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, School of Brain and Cognitive Sciences, Beijing Normal University, Beijing 100875, China
| | - Yousheng Shu
- State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, School of Brain and Cognitive Sciences, Beijing Normal University, Beijing 100875, China.
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46
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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.
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47
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Xu NZ, Ernst M, Treven M, Cerne R, Wakulchik M, Li X, Jones TM, Gleason SD, Morrow D, Schkeryantz JM, Rahman MT, Li G, Poe MM, Cook JM, Witkin JM. Negative allosteric modulation of alpha 5-containing GABA A receptors engenders antidepressant-like effects and selectively prevents age-associated hyperactivity in tau-depositing mice. Psychopharmacology (Berl) 2018; 235:1151-1161. [PMID: 29374303 DOI: 10.1007/s00213-018-4832-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 01/07/2018] [Indexed: 02/08/2023]
Abstract
RATIONALE Associated with frank neuropathology, patients with Alzheimer's disease suffer from a host of neuropsychiatric symptoms that include depression, apathy, agitation, and aggression. Negative allosteric modulators (NAMs) of α5-containing GABAA receptors have been suggested to be a novel target for antidepressant action. We hypothesized that pharmacological modulation of this target would engender increased motivation in stressful environments. METHODS We utilized electrophysiological recordings from Xenopus oocytes and behavioral measures in mice to address this hypothesis. RESULTS In the forced-swim assay in mice that detects antidepressant drugs, the α5β3γ2 GABAΑ receptor NAM, RY-080 produced a marked antidepressant phenotype. Another compound, PWZ-029, was characterized as an α5β3γ2 receptor NAM of lower intrinsic efficacy in electrophysiological studies in Xenopus oocytes. In contrast to RY-080, PWZ-029 was only moderately active in the forced-swim assay and the α5β3γ2 receptor antagonist, Xli-093, was not active at all. The effects of RY-080 were prevented by the non-selective benzodiazepine receptor antagonist flumazenil as well as by the selective ligands, PWZ-029 and Xli-093. These findings demonstrate that this effect of RY-080 is driven by negative allosteric modulation of α5βγ2 GABAA receptors. RY-080 was not active in the tail-suspension test. We also demonstrated a reduction in the age-dependent hyperactivity exhibited by transgenic mice that accumulate pathological tau (rTg4510 mice) by RY-080. The decrease in hyperactivity by RY-080 was selective for the hyperactivity of the rTg4510 mice since the locomotion of control strains of mice were not significantly affected by RY-080. CONCLUSIONS α5βγ2 GABAA receptor NAMs might function as a pharmacological treatment for mood, amotivational syndromes, and psychomotor agitation in patients with Alzheimer's and other neurodegenerative disorders.
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Affiliation(s)
- Nina Z Xu
- The Lilly Research Labs, Eli Lilly and Company, Indianapolis, IN, USA
| | - Margot Ernst
- Department of Molecular Neurosciences Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| | - Marco Treven
- Department of Molecular Neurosciences Center for Brain Research, Medical University of Vienna, Spitalgasse 4, Vienna, Austria
| | - Rok Cerne
- The Lilly Research Labs, Eli Lilly and Company, Indianapolis, IN, USA
| | - Mark Wakulchik
- The Lilly Research Labs, Eli Lilly and Company, Indianapolis, IN, USA
| | - Xia Li
- The Lilly Research Labs, Eli Lilly and Company, Indianapolis, IN, USA
| | - Timothy M Jones
- The Lilly Research Labs, Eli Lilly and Company, Indianapolis, IN, USA
| | - Scott D Gleason
- The Lilly Research Labs, Eli Lilly and Company, Indianapolis, IN, USA
| | - Denise Morrow
- The Lilly Research Labs, Eli Lilly and Company, Indianapolis, IN, USA
| | | | - Md Toufiqur Rahman
- Department of Chemistry and Biochemistry, University of Wisconsin Milwaukee, Milwaukee, WI, USA
| | - Guanguan Li
- Department of Chemistry and Biochemistry, University of Wisconsin Milwaukee, Milwaukee, WI, USA
| | - Michael M Poe
- Department of Chemistry and Biochemistry, University of Wisconsin Milwaukee, Milwaukee, WI, USA
| | - James M Cook
- Department of Chemistry and Biochemistry, University of Wisconsin Milwaukee, Milwaukee, WI, USA
| | - Jeffrey M Witkin
- The Lilly Research Labs, Eli Lilly and Company, Indianapolis, IN, USA.
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48
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Domínguez S, Fernández de Sevilla D, Buño W. Acetylcholine Facilitates a Depolarization-Induced Enhancement of Inhibition in Rat CA1 Pyramidal Neurons. Cereb Cortex 2018; 27:852-862. [PMID: 26620268 DOI: 10.1093/cercor/bhv276] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Cholinergic mechanisms in the hippocampus regulate forms of synaptic plasticity linked with cognition and spatial navigation, but the underlying mechanisms remain largely unknown. Here, in rat hippocampal CA1 pyramidal cells under blockade of ionotropic glutamate receptors, we report that a single acetylcholine pulse and repeated depolarization activated a robust and enduring postsynaptic depolarization-induced enhancement of inhibition (DEI) that masked a presynaptic depolarization-induced suppression of inhibition (DSI). Increased cytosolic Ca2+ and M1-muscarinic receptor activation caused the rise in voltage-sensitive α5βγ2-containing γ-aminobutyric acid type-A receptors that generated DEI. In summary, this muscarinic-mediated activity-dependent plasticity rapidly transfers depolarization effects on inhibition from presynaptic suppression or DSI to postsynaptic enhancement or DEI, a change potentially relevant in behavior.
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Affiliation(s)
| | - David Fernández de Sevilla
- Instituto Cajal, CSIC, 28002 Madrid, Spain.,Depto. Anatomía, Histología y Neurociencia, Facultad de Medicina UAM, 28029 Madrid, Spain
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Abbas G, Mahmood W, Kabir N. Recent progress on the role of GABAergic neurotransmission in the pathogenesis of Alzheimer's disease. Rev Neurosci 2018; 27:449-55. [PMID: 26812781 DOI: 10.1515/revneuro-2015-0062] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Accepted: 11/29/2015] [Indexed: 12/15/2022]
Abstract
Despite their possible causative role, targeting amyloidosis, tau phosphorylation, acetylcholine esterase, glutamate, oxidative stress and mitochondrial metabolism have not yet led to the development of drugs to cure Alzheimer's disease (AD). Recent preclinical and clinical reports exhibit a surge in interest in the role of GABAergic neurotransmission in the pathogenesis of AD. The interaction among GABAergic signaling, amyloid-β and acetylcholine is shown to affect the homeostasis between excitation (glutamate) and inhibition (GABA) in the brain. As a consequence, over-excitation leads to neurodegeneration (excitotoxicity) and impairment in the higher level functions. Previously, the glutamate arm of this balance received the most attention. Recent literature suggests that over-excitation is primarily mediated by dysfunctional GABA signaling and can possibly be restored by rectifying anomalous metabolism observed in the GABAergic neurons during AD. Additionally, neurogenesis and synaptogenesis have also been linked with GABAergic signaling. This association may provide a basis for the needed repair mechanism. Furthermore, several preclinical interventional studies revealed that targeting various GABA receptor subtypes holds potential in overcoming the memory deficits associated with AD. In conclusion, the recent scientific literature suggests that GABAergic signaling presents itself as a promising target for anti-AD drug development.
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50
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Chandler CM, Overton JS, Rüedi-Bettschen D, Platt DM. GABA A Receptor Subtype Mechanisms and the Abuse-Related Effects of Ethanol: Genetic and Pharmacological Evidence. Handb Exp Pharmacol 2018; 248:3-27. [PMID: 29204713 DOI: 10.1007/164_2017_80] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Ethanol's reinforcing and subjective effects, as well as its ability to induce relapse, are powerful factors contributing to its widespread use and abuse. A significant mediator of these behavioral effects is the GABAA receptor system. GABAA receptors are the target for γ-aminobutyric acid (GABA), the major inhibitory neurotransmitter in the CNS. Structurally, they are pentameric, transmembrane chloride ion channels comprised of subunits from at least eight different families of distinct proteins. The contribution of different GABAA subunits to ethanol's diverse abuse-related effects is not clear and remains an area of research focus. This chapter details the clinical and preclinical findings supporting roles for different α, β, γ, and δ subunit-containing GABAA receptors in ethanol's reinforcing, subjective/discriminative stimulus, and relapse-inducing effects. The reinforcing properties of ethanol have been studied the most systematically, and convergent preclinical evidence suggests a key role for the α5 subunit in those effects. Regarding ethanol's subjective/discriminative stimulus effects, clinical and genetic findings support a primary role for the α2 subunit, whereas preclinical evidence implicates the α5 subunit. At present, too few studies investigating ethanol relapse exist to make any solid conclusions regarding the role of specific GABAA subunits in this abuse-related effect.
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Affiliation(s)
- Cassie M Chandler
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS, USA
| | - John S Overton
- Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, MS, USA
| | - Daniela Rüedi-Bettschen
- Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, MS, USA
| | - Donna M Platt
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS, USA.
- Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, MS, USA.
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