1
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Osse AML, Pandey RS, Wirt RA, Ortiz AA, Salazar A, Kimmich M, Toledano Strom EN, Oblak A, Lamb B, Hyman JM, Carter GW, Kinney J. Reduction in GABAB on glia induce Alzheimer's disease related changes. Brain Behav Immun 2023; 110:260-275. [PMID: 36906075 PMCID: PMC10115139 DOI: 10.1016/j.bbi.2023.03.002] [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: 10/25/2022] [Revised: 02/26/2023] [Accepted: 03/01/2023] [Indexed: 03/13/2023] Open
Abstract
Alzheimer's Disease (AD) is a neurodegenerative disorder characterized by beta-amyloid plaques (Aβ), neurofibrillary tangles (NFT), and neuroinflammation. Data have demonstrated that neuroinflammation contributes to Aβ and NFT onset and progression, indicating inflammation and glial signaling is vital to understanding AD. A previous investigation demonstrated a significant decrease of the GABAB receptor (GABABR) in APP/PS1 mice (Salazar et al., 2021). To determine if changes in GABABR restricted to glia serve a role in AD, we developed a mouse model with a reduction of GABABR restricted to macrophages, GAB/CX3ert. This model exhibits changes in gene expression and electrophysiological alterations similar to amyloid mouse models of AD. Crossing the GAB/CX3ert mouse with APP/PS1 resulted in significant increases in Aβ pathology. Our data demonstrates that decreased GABABR on macrophages leads to several changes observed in AD mouse models, as well as exacerbation of AD pathology when crossed with existing models. These data suggest a novel mechanism in AD pathogenesis.
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Affiliation(s)
- Amanda M Leisgang Osse
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States.
| | - Ravi S Pandey
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, United States
| | - Ryan A Wirt
- University of Nevada, Las Vegas, Department of Psychology, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Andrew A Ortiz
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Arnold Salazar
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Michael Kimmich
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Erin N Toledano Strom
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Adrian Oblak
- Indiana University, School of Medicine, 340 W 10(th) Street, Indianapolis, IN 46202, United States
| | - Bruce Lamb
- Indiana University, School of Medicine, 340 W 10(th) Street, Indianapolis, IN 46202, United States
| | - James M Hyman
- University of Nevada, Las Vegas, Department of Psychology, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
| | - Gregory W Carter
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, United States
| | - Jefferson Kinney
- University of Nevada, Las Vegas, Department of Brain Health, 4505 S. Maryland Parkway, Las Vegas, NV 89154, United States
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2
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Cheng YT, Luna-Figueroa E, Woo J, Chen HC, Lee ZF, Harmanci AS, Deneen B. Inhibitory input directs astrocyte morphogenesis through glial GABA BR. Nature 2023; 617:369-376. [PMID: 37100909 PMCID: PMC10733939 DOI: 10.1038/s41586-023-06010-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 03/23/2023] [Indexed: 04/28/2023]
Abstract
Communication between neurons and glia has an important role in establishing and maintaining higher-order brain function1. Astrocytes are endowed with complex morphologies, placing their peripheral processes in close proximity to neuronal synapses and directly contributing to their regulation of brain circuits2-4. Recent studies have shown that excitatory neuronal activity promotes oligodendrocyte differentiation5-7; whether inhibitory neurotransmission regulates astrocyte morphogenesis during development is unclear. Here we show that inhibitory neuron activity is necessary and sufficient for astrocyte morphogenesis. We found that input from inhibitory neurons functions through astrocytic GABAB receptor (GABABR) and that its deletion in astrocytes results in a loss of morphological complexity across a host of brain regions and disruption of circuit function. Expression of GABABR in developing astrocytes is regulated in a region-specific manner by SOX9 or NFIA and deletion of these transcription factors results in region-specific defects in astrocyte morphogenesis, which is conferred by interactions with transcription factors exhibiting region-restricted patterns of expression. Together, our studies identify input from inhibitory neurons and astrocytic GABABR as universal regulators of morphogenesis, while further revealing a combinatorial code of region-specific transcriptional dependencies for astrocyte development that is intertwined with activity-dependent processes.
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Affiliation(s)
- Yi-Ting Cheng
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston, TX, USA
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX, USA
| | - Estefania Luna-Figueroa
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston, TX, USA
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, TX, USA
| | - Junsung Woo
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston, TX, USA
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, TX, USA
| | - Hsiao-Chi Chen
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston, TX, USA
- Cancer Cell Biology Graduate Program, Baylor College of Medicine, Houston, TX, USA
| | - Zhung-Fu Lee
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston, TX, USA
- Development, Disease, Models and Therapeutics Graduate Program, Baylor College of Medicine, Houston, TX, USA
| | - Akdes Serin Harmanci
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston, TX, USA
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, TX, USA
| | - Benjamin Deneen
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston, TX, USA.
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX, USA.
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, TX, USA.
- Cancer Cell Biology Graduate Program, Baylor College of Medicine, Houston, TX, USA.
- Development, Disease, Models and Therapeutics Graduate Program, Baylor College of Medicine, Houston, TX, USA.
- Department of Neurosurgery, Baylor College of Medicine, Houston, TX, USA.
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3
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Di Giorgio NP, Bizzozzero-Hiriart M, Surkin PN, Repetto E, Bonaventura MM, Tabares FN, Bourguignon NS, Converti A, Gomez JMR, Bettler B, Lux-Lantos V. Deletion of GABAB receptors from Kiss1 cells affects glucose homeostasis without altering reproduction in male mice. Am J Physiol Endocrinol Metab 2023; 324:E314-E329. [PMID: 36652400 DOI: 10.1152/ajpendo.00129.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Kisspeptin and γ-amino butyric acid (GABA), synthesized in the central nervous system, are critical for reproduction. Both are also expressed in peripheral organs/tissues critical to metabolic control (liver/pancreas/adipose). Many kisspeptin neurons coexpress GABAB receptors (GABABR) and GABA controls kisspeptin expression and secretion. We developed a unique mouse lacking GABABR exclusively from kisspeptin cells/neurons (Kiss1-GABAB1KO) to evaluate the impact on metabolism/reproduction. We confirmed selective deletion of GABABR from Kiss1 cells in the anteroventral periventricular nucleus/periventricular nucleus continuum (AVPV/PeN; immunofluorescence and PCR) and arcuate nucleus (ARC), medial amygdala (MeA), pituitary, liver, and testes (PCR). Young Kiss1-GABAB1KO males were fertile, with normal LH and testosterone. Kiss1 expression was similar between genotypes in AVPV/PeN, ARC, MeA, bed nucleus of the stria terminalis (BNST), and peripheral organs (testis, liver, pituitary). Kiss1-GABAB1KO males presented higher fasted glycemia and insulin levels, an impaired response to a glucose overload, reduced insulin sensitivity, and marked insulin resistance. Interestingly, when Kiss1-GABAB1KO males got older (9 mo old) their body weight (BW) increased, in part due to an increase in white adipose tissue (WAT). Old Kiss1-GABAB1KO males showed higher fasted insulin, increased pancreatic insulin content, insulin resistance, and significantly decreased pancreatic kisspeptin levels. In sum, lack of GABABR specifically in Kiss1 cells severely impacts glucose homeostasis in male mice, reinforcing kisspeptin involvement in metabolic regulation. These alterations in glucose homeostasis worsened with aging. We highlight the impact of GABA through GABABR in the regulation of the pancreas kisspeptin system in contrast to liver kisspeptin that was not affected.NEW & NOTEWORTHY We developed a unique mouse lacking GABAB receptors specifically in Kiss1 cells to evaluate the impact on reproduction and metabolism. Knockout males showed a severe impact on glucose homeostasis, which worsened with aging. These results reinforce the proposed kisspeptin involvement in metabolic regulation and highlight the impact of GABA through GABABR in the regulation of the peripheral pancreas kisspeptin system.
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Affiliation(s)
- Noelia P Di Giorgio
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
| | - Marianne Bizzozzero-Hiriart
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
| | - Pablo N Surkin
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
| | - Esteban Repetto
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
| | - María M Bonaventura
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
| | - Florencia N Tabares
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
| | - Nadia S Bourguignon
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
| | - Ayelén Converti
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
| | - Juan M Riaño Gomez
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
| | - Bernhard Bettler
- Department of Biomedicine, Pharmazentrum, University of Basel, Basel, Switzerland
| | - Victoria Lux-Lantos
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
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4
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Cheng YT, Luna-Figueroa E, Woo J, Chen HC, Lee ZF, Harmanci AS, Deneen B. Inhibitory input directs astrocyte morphogenesis through glial GABA B R. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.14.532493. [PMID: 36993256 PMCID: PMC10054985 DOI: 10.1101/2023.03.14.532493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Communication between neurons and glia plays an important role in establishing and maintaining higher order brain function. Astrocytes are endowed with complex morphologies which places their peripheral processes in close proximity to neuronal synapses and directly contributes to their regulation of brain circuits. Recent studies have shown that excitatory neuronal activity promotes oligodendrocyte differentiation; whether inhibitory neurotransmission regulates astrocyte morphogenesis during development is unknown. Here we show that inhibitory neuron activity is necessary and sufficient for astrocyte morphogenesis. We found that input from inhibitory neurons functions through astrocytic GABA B R and that its deletion in astrocytes results in a loss of morphological complexity across a host of brain regions and disruption of circuit function. Expression of GABA B R in developing astrocytes is regulated in a region-specific manner by SOX9 or NFIA and deletion of these transcription factors results in region-specific defects in astrocyte morphogenesis, which is conferred by interactions with transcription factors exhibiting region-restricted patterns of expression. Together our studies identify input from inhibitory neurons and astrocytic GABA B R as universal regulators of morphogenesis, while further revealing a combinatorial code of region-specific transcriptional dependencies for astrocyte development that is intertwined with activity-dependent processes.
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Affiliation(s)
- Yi-Ting Cheng
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston TX 77030
- Program in Developmental Biology, Baylor College of Medicine, Houston TX 77030
| | - Estefania Luna-Figueroa
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston TX 77030
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston TX 77030
| | - Junsung Woo
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston TX 77030
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston TX 77030
| | - Hsiao-Chi Chen
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston TX 77030
- Cancer Cell Biology Graduate Program, Baylor College of Medicine, Houston TX 77030
| | - Zhung-Fu Lee
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston TX 77030
- Development, Disease, Models, and Therapeutics Graduate Program, Baylor College of Medicine, Houston, TX 77030
| | - Akdes Serin Harmanci
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston TX 77030
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston TX 77030
| | - Benjamin Deneen
- Center for Cancer Neuroscience, Baylor College of Medicine, Houston TX 77030
- Program in Developmental Biology, Baylor College of Medicine, Houston TX 77030
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston TX 77030
- Development, Disease, Models, and Therapeutics Graduate Program, Baylor College of Medicine, Houston, TX 77030
- Cancer Cell Biology Graduate Program, Baylor College of Medicine, Houston TX 77030
- Department of Neurosurgery, Baylor College of Medicine, Houston TX 77030
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5
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Mederos S, Sánchez-Ruiz A, Perea G. Protocol to downregulate GABAergic-astrocyte signaling via astrocyte-selective ablation of GABA B receptor in adult mice. STAR Protoc 2022; 3:101667. [PMID: 36103305 PMCID: PMC9483643 DOI: 10.1016/j.xpro.2022.101667] [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: 05/19/2022] [Revised: 07/07/2022] [Accepted: 08/03/2022] [Indexed: 01/25/2023] Open
Abstract
Here, we present a protocol to selectively downregulate GABAB receptor (GABABR) expression in astrocytes of mouse medial prefrontal cortex (mPFC). We first describe the procedure of surgeries and viral injections. We then detail genetic, histological, and functional characterizations of astrocytic GABABR ablation using RT-PCR, imaging, and behavioral assays. The use of GABAB flox mice can be easily adapted to generate astrocyte-selective GABABR ablation in different brain areas and postnatal stages, leading to local downregulation of GABAergic-astrocyte signaling without developmental issues. For complete details on the use and execution of this protocol, please refer to Mederos et al. (2021).
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Affiliation(s)
- Sara Mederos
- Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, London W1T 4JG, UK,Corresponding author
| | | | - Gertrudis Perea
- Neuron-Glia Networks Lab. Cajal Institute, CSIC, Madrid 28002, Spain,Corresponding author
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6
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Impaired bidirectional communication between interneurons and oligodendrocyte precursor cells affects social cognitive behavior. Nat Commun 2022; 13:1394. [PMID: 35296664 PMCID: PMC8927409 DOI: 10.1038/s41467-022-29020-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 02/23/2022] [Indexed: 12/13/2022] Open
Abstract
Cortical neural circuits are complex but very precise networks of balanced excitation and inhibition. Yet, the molecular and cellular mechanisms that form the balance are just beginning to emerge. Here, using conditional γ-aminobutyric acid receptor B1- deficient mice we identify a γ-aminobutyric acid/tumor necrosis factor superfamily member 12-mediated bidirectional communication pathway between parvalbumin-positive fast spiking interneurons and oligodendrocyte precursor cells that determines the density and function of interneurons in the developing medial prefrontal cortex. Interruption of the GABAergic signaling to oligodendrocyte precursor cells results in reduced myelination and hypoactivity of interneurons, strong changes of cortical network activities and impaired social cognitive behavior. In conclusion, glial transmitter receptors are pivotal elements in finetuning distinct brain functions. Early postnatal interruption of the bidirectional GABA/TNFSF12 signaling between parvalbumin-positive interneurons and oligodendrocyte precursor cells impairs correct prefrontal cortical network activity and social cognitive behavior later in life.
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7
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Sun R, Tsunekawa T, Hirose T, Yaginuma H, Taki K, Mizoguchi A, Miyata T, Kobayashi T, Sugiyama M, Onoue T, Takagi H, Hagiwara D, Ito Y, Iwama S, Suga H, Banno R, Bettler B, Arima H. GABA B receptor signaling in the caudate putamen is involved in binge-like consumption during a high fat diet in mice. Sci Rep 2021; 11:19296. [PMID: 34588513 PMCID: PMC8481241 DOI: 10.1038/s41598-021-98590-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 09/08/2021] [Indexed: 11/29/2022] Open
Abstract
Previous studies suggest that signaling by the gamma-aminobutyric acid (GABA) type B receptor (GABABR) is involved in the regulation of binge eating, a disorder which might contribute to the development of obesity. Here, we show that intermittent access to a high fat diet (HFD) induced binge-like eating behavior with activation of dopamine receptor d1 (drd1)-expressing neurons in the caudate putamen (CPu) and nucleus accumbens (NAc) in wild-type (WT) mice. The activation of drd1-expressing neurons during binge-like eating was substantially increased in the CPu, but not in the NAc, in corticostriatal neuron-specific GABABR-deficient knockout (KO) mice compared to WT mice. Treatment with the GABABR agonist, baclofen, suppressed binge-like eating behavior in WT mice, but not in KO mice, as reported previously. Baclofen also suppressed the activation of drd1-expressing neurons in the CPu, but not in the NAc, during binge-like eating in WT mice. Thus, our data suggest that GABABR signaling in CPu neurons expressing drd1 suppresses binge-like consumption during a HFD in mice.
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Affiliation(s)
- Runan Sun
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Taku Tsunekawa
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan.
- Department of Endocrinology and Diabetes, Ichinomiya Municipal Hospital, 2-2-22, Bunkyo, Ichinomiya, 491-8558, Japan.
| | - Tomonori Hirose
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Hiroshi Yaginuma
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Keigo Taki
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Akira Mizoguchi
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
- Department of Endocrinology and Diabetes, Ichinomiya Municipal Hospital, 2-2-22, Bunkyo, Ichinomiya, 491-8558, Japan
| | - Takashi Miyata
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Tomoko Kobayashi
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Mariko Sugiyama
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Takeshi Onoue
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Hiroshi Takagi
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Daisuke Hagiwara
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Yoshihiro Ito
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Shintaro Iwama
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Hidetaka Suga
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
| | - Ryoichi Banno
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan
- Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, 464-8601, Japan
| | - Bernhard Bettler
- Department of Biomedicine, University of Basel, 4056, Basel, Switzerland
| | - Hiroshi Arima
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan.
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8
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Favuzzi E, Huang S, Saldi GA, Binan L, Ibrahim LA, Fernández-Otero M, Cao Y, Zeine A, Sefah A, Zheng K, Xu Q, Khlestova E, Farhi SL, Bonneau R, Datta SR, Stevens B, Fishell G. GABA-receptive microglia selectively sculpt developing inhibitory circuits. Cell 2021; 184:4048-4063.e32. [PMID: 34233165 PMCID: PMC9122259 DOI: 10.1016/j.cell.2021.06.018] [Citation(s) in RCA: 125] [Impact Index Per Article: 41.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 03/31/2021] [Accepted: 06/10/2021] [Indexed: 01/14/2023]
Abstract
Microglia, the resident immune cells of the brain, have emerged as crucial regulators of synaptic refinement and brain wiring. However, whether the remodeling of distinct synapse types during development is mediated by specialized microglia is unknown. Here, we show that GABA-receptive microglia selectively interact with inhibitory cortical synapses during a critical window of mouse postnatal development. GABA initiates a transcriptional synapse remodeling program within these specialized microglia, which in turn sculpt inhibitory connectivity without impacting excitatory synapses. Ablation of GABAB receptors within microglia impairs this process and leads to behavioral abnormalities. These findings demonstrate that brain wiring relies on the selective communication between matched neuronal and glial cell types.
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Affiliation(s)
- Emilia Favuzzi
- Department of Neurobiology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Shuhan Huang
- Department of Neurobiology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Giuseppe A Saldi
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Department of Biology, New York University, New York, NY 10003, USA
| | - Loïc Binan
- Klarman Cell Observatory, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Leena A Ibrahim
- Department of Neurobiology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Marian Fernández-Otero
- Department of Neurobiology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Yuqing Cao
- Department of Neurobiology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Ayman Zeine
- Department of Neurobiology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Adwoa Sefah
- Department of Neurobiology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Karen Zheng
- Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Qing Xu
- New York University Abu Dhabi, Abu Dhabi, UAE
| | - Elizaveta Khlestova
- Department of Neurobiology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Samouil L Farhi
- Klarman Cell Observatory, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Richard Bonneau
- Department of Biology, New York University, New York, NY 10003, USA; Center for Computational Biology, Flatiron Institute, New York, NY 10010, USA; Center for Data Science, New York University, New York, NY 10011, USA
| | - Sandeep Robert Datta
- Department of Neurobiology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Beth Stevens
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Boston Children's Hospital, F.M. Kirby Neurobiology Center, Boston, MA 02115, USA
| | - Gord Fishell
- Department of Neurobiology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.
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9
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Ramírez-Ayala LC, Rocha D, Ramos-Onsins SE, Leno-Colorado J, Charles M, Bouchez O, Rodríguez-Valera Y, Pérez-Enciso M, Ramayo-Caldas Y. Whole-genome sequencing reveals insights into the adaptation of French Charolais cattle to Cuban tropical conditions. Genet Sel Evol 2021; 53:3. [PMID: 33397281 PMCID: PMC7784321 DOI: 10.1186/s12711-020-00597-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 12/11/2020] [Indexed: 02/01/2023] Open
Abstract
Background In the early 20th century, Cuban farmers imported Charolais cattle (CHFR) directly from France. These animals are now known as Chacuba (CHCU) and have become adapted to the rough environmental tropical conditions in Cuba. These conditions include long periods of drought and food shortage with extreme temperatures that European taurine cattle have difficulty coping with. Results In this study, we used whole-genome sequence data from 12 CHCU individuals together with 60 whole-genome sequences from six additional taurine, indicus and crossed breeds to estimate the genetic diversity, structure and accurate ancestral origin of the CHCU animals. Although CHCU animals are assumed to form a closed population, the results of our admixture analysis indicate a limited introgression of Bos indicus. We used the extended haplotype homozygosity (EHH) approach to identify regions in the genome that may have had an important role in the adaptation of CHCU to tropical conditions. Putative selection events occurred in genomic regions with a high proportion of Bos indicus, but they were not sufficient to explain adaptation of CHCU to tropical conditions by Bos indicus introgression only. EHH suggested signals of potential adaptation in genomic windows that include genes of taurine origin involved in thermogenesis (ATP9A, GABBR1, PGR, PTPN1 and UCP1) and hair development (CCHCR1 and CDSN). Within these genes, we identified single nucleotide polymorphisms (SNPs) that may have a functional impact and contribute to some of the observed phenotypic differences between CHCU and CHFR animals. Conclusions Whole-genome data confirm that CHCU cattle are closely related to Charolais from France (CHFR) and Canada, but also reveal a limited introgression of Bos indicus genes in CHCU. We observed possible signals of recent adaptation to tropical conditions between CHCU and CHFR founder populations, which were largely independent of the Bos indicus introgression. Finally, we report candidate genes and variants that may have a functional impact and explain some of the phenotypic differences observed between CHCU and CHFR cattle.
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Affiliation(s)
- Lino C Ramírez-Ayala
- Plant and Animal Genomics, Centre de Recerca en Agrigenòmica (CRAG) CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Spain
| | - Dominique Rocha
- Université Paris-Saclay, INRAE, Jouy-En-Josas, AgroParisTech, GABI, 78350, France
| | - Sebas E Ramos-Onsins
- Plant and Animal Genomics, Centre de Recerca en Agrigenòmica (CRAG) CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Spain
| | - Jordi Leno-Colorado
- Plant and Animal Genomics, Centre de Recerca en Agrigenòmica (CRAG) CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Spain
| | - Mathieu Charles
- Université Paris-Saclay, INRAE, Jouy-En-Josas, AgroParisTech, GABI, 78350, France.,INRAE, SIGENAE, Jouy-En-Josas, 78350, France
| | - Olivier Bouchez
- INRAE, GeT-PlaGe, Genotoul, Castanet-Tolosan, US, 1426, France
| | | | - Miguel Pérez-Enciso
- Plant and Animal Genomics, Centre de Recerca en Agrigenòmica (CRAG) CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Spain.,Institut Català de Recerca I Estudis Avançats (ICREA), Barcelona, Spain
| | - Yuliaxis Ramayo-Caldas
- Université Paris-Saclay, INRAE, Jouy-En-Josas, AgroParisTech, GABI, 78350, France. .,Animal Breeding and Genetics Program, Institute for Research and Technology in Food and Agriculture (IRTA), Torre Marimon, Caldes De Montbui, 08140, Spain.
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10
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Mederos S, Sánchez-Puelles C, Esparza J, Valero M, Ponomarenko A, Perea G. GABAergic signaling to astrocytes in the prefrontal cortex sustains goal-directed behaviors. Nat Neurosci 2020; 24:82-92. [PMID: 33288910 DOI: 10.1038/s41593-020-00752-x] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 11/02/2020] [Indexed: 12/18/2022]
Abstract
GABA interneurons play a critical role in higher brain functions. Astrocytic glial cells interact with synapses throughout the whole brain and are recognized as regulatory elements of excitatory synaptic transmission. However, it is largely unknown how GABAergic interneurons and astrocytes interact and contribute to stable performance of complex behaviors. Here, we found that genetic ablation of GABAB receptors in medial prefrontal cortex astrocytes altered low-gamma oscillations and firing properties of cortical neurons, which affected goal-directed behaviors. Remarkably, working memory deficits were restored by optogenetic stimulation of astrocytes with melanopsin. Furthermore, melanopsin-activated astrocytes in wild-type mice enhanced the firing rate of cortical neurons and gamma oscillations, as well as improved cognition. Therefore, our work identifies astrocytes as a hub for controlling inhibition in cortical circuits, providing a novel pathway for the behaviorally relevant midrange time-scale regulation of cortical information processing and consistent goal-directed behaviors.
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Affiliation(s)
| | | | | | - Manuel Valero
- NYU Neuroscience Institute, New York University Langone Medical Center, New York, NY, USA
| | - Alexey Ponomarenko
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Institute of Clinical Neuroscience and Medical Psychology, Medical Faculty, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany.,NeuroCure Cluster of Excellence, Leibniz-Institut für Molekulare Pharmakologie (FMP), Berlin, Germany
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11
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Metabolomic Analysis of Plasma from GABAB(1) Knock-Out Mice Reveals Decreased Levels of Elaidic Trans-Fatty Acid. Metabolites 2020; 10:metabo10120484. [PMID: 33255896 PMCID: PMC7760308 DOI: 10.3390/metabo10120484] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/20/2020] [Accepted: 11/22/2020] [Indexed: 11/17/2022] Open
Abstract
Mice lacking the GABAB(1) subunit of gamma-aminobutyric acid (GABA) type B receptors exhibit spontaneous seizures, hyperalgesia, hyperlocomotor activity, and memory impairment. Although mice lacking the GABAB(1) subunit are viable, they are sterile, and to generate knockout (KO) mice, it is necessary to cross heterozygous (HZ) mice. The aim of our study was to detect the metabolic differences between the three genotypes of GABAB(1) KO mice in order to further characterize this experimental animal model. Plasma samples were collected from wild-type (WT), HZ, and KO mice. Samples were analyzed by means of a gas chromatography-mass spectrometry (GC-MS) platform. Univariate t-test, and partial least square discriminant analysis (PLS-DA) were performed to compare the metabolic pattern of different genotypes. The metabolomic analysis highlighted differences between the three genotypes and identified some metabolites less abundant in KO mice, namely elaidic acid and other fatty acids, and chiro-inositol.
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12
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Neonatal Clonazepam Administration Induced Long-Lasting Changes in GABA A and GABA B Receptors. Int J Mol Sci 2020; 21:ijms21093184. [PMID: 32366006 PMCID: PMC7246485 DOI: 10.3390/ijms21093184] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/24/2020] [Accepted: 04/28/2020] [Indexed: 11/17/2022] Open
Abstract
Benzodiazepines (BZDs) are widely used in patients of all ages. Unlike adults, neonatal animals treated with BZDs exhibit a variety of behavioral deficits later in life; however, the mechanisms underlying these deficits are poorly understood. This study aims to examine whether administration of clonazepam (CZP; 1 mg/kg/day) in 7-11-day-old rats affects Gama aminobutyric acid (GABA)ergic receptors in both the short and long terms. Using RT-PCR and quantitative autoradiography, we examined the expression of the selected GABAA receptor subunits (α1, α2, α4, γ2, and δ) and the GABAB B2 subunit, and GABAA, benzodiazepine, and GABAB receptor binding 48 h, 1 week, and 2 months after treatment discontinuation. Within one week after CZP cessation, the expression of the α2 subunit was upregulated, whereas that of the δ subunit was downregulated in both the hippocampus and cortex. In the hippocampus, the α4 subunit was downregulated after the 2-month interval. Changes in receptor binding were highly dependent on the receptor type, the interval after treatment cessation, and the brain structure. GABAA receptor binding was increased in almost all of the brain structures after the 48-h interval. BZD-binding was decreased in many brain structures involved in the neuronal networks associated with emotional behavior, anxiety, and cognitive functions after the 2-month interval. Binding of the GABAB receptors changed depending on the interval and brain structure. Overall, the described changes may affect both synaptic development and functioning and may potentially cause behavioral impairment.
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13
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Liu JH, Li ZL, Liu YS, Chu HD, Hu NY, Wu DY, Huang L, Li SJ, Li XW, Yang JM, Gao TM. Astrocytic GABA B Receptors in Mouse Hippocampus Control Responses to Behavioral Challenges through Astrocytic BDNF. Neurosci Bull 2020; 36:705-718. [PMID: 32166647 DOI: 10.1007/s12264-020-00474-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 10/28/2019] [Indexed: 02/06/2023] Open
Abstract
Major depressive disorder (MDD) is a common mood disorder that affects almost 20% of the global population. In addition, much evidence has implicated altered function of the gamma-aminobutyric acid (GABAergic) system in the pathophysiology of depression. Recent research has indicated that GABAB receptors (GABABRs) are an emerging therapeutic target in the treatment of stress-related disorders such as MDD. However, which cell types with GABABRs are involved in this process is unknown. As hippocampal dysfunction is implicated in MDD, we knocked down GABABRs in the hippocampus and found that knocking down these receptors in astrocytes, but not in GABAergic or pyramidal neurons, caused a decrease in immobility in the forced swimming test (FST) without affecting other anxiety- and depression-related behaviors. We also generated astrocyte-specific GABABR-knockout mice and found decreased immobility in the FST in these mice. Furthermore, the conditional knockout of GABABRs in astrocytes selectively increased the levels of brain-derived neurotrophic factor protein in hippocampal astrocytes, which controlled the decrease in immobility in the FST. Taken together, our findings contribute to the current understanding of which cell types expressing GABABRs modulate antidepressant activity in the FST, and they may provide new insights into the pathological mechanisms and potential targets for the treatment of depression.
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Affiliation(s)
- Ji-Hong Liu
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Ze-Lin Li
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Yi-Si Liu
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Huai-De Chu
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Neng-Yuan Hu
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Ding-Yu Wu
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Lang Huang
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Shu-Ji Li
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Xiao-Wen Li
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Jian-Ming Yang
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
| | - Tian-Ming Gao
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Key Laboratory of Psychiatric Disorders, Collaborative Innovation Center for Brain Science, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China.
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14
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Chang W, Tu CL, Jean-Alphonse FG, Herberger A, Cheng Z, Hwong J, Ho H, Li A, Wang D, Liu H, White AD, Suh I, Shen W, Duh QY, Khanafshar E, Shoback DM, Xiao K, Vilardaga JP. PTH hypersecretion triggered by a GABA B1 and Ca 2+-sensing receptor heterocomplex in hyperparathyroidism. Nat Metab 2020; 2:243-255. [PMID: 32694772 PMCID: PMC7377265 DOI: 10.1038/s42255-020-0175-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 01/20/2020] [Indexed: 12/14/2022]
Abstract
Molecular mechanisms mediating tonic secretion of parathyroid hormone (PTH) in response to hypocalcaemia and hyperparathyroidism (HPT) are unclear. Here we demonstrate increased heterocomplex formation between the calcium-sensing receptor (CaSR) and metabotropic γ-aminobutyric acid (GABA) B1 receptor (GABAB1R) in hyperplastic parathyroid glands (PTGs) of patients with primary and secondary HPT. Targeted ablation of GABAB1R or glutamic acid decarboxylase 1 and 2 in PTGs produces hypocalcaemia and hypoparathyroidism, and prevents PTH hypersecretion in PTGs cultured from mouse models of hereditary HPT and dietary calcium-deficiency. Cobinding of the CaSR/GABAB1R complex by baclofen and high extracellular calcium blocks the coupling of heterotrimeric G-proteins to homomeric CaSRs in cultured cells and promotes PTH secretion in cultured mouse PTGs. These results combined with the ability of PTG to synthesize GABA support a critical autocrine action of GABA/GABAB1R in mediating tonic PTH secretion of PTGs and ascribe aberrant activities of CaSR/GABAB1R heteromer to HPT.
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Affiliation(s)
- Wenhan Chang
- Endocrine Research Unit, Department of Veterans Affairs Medical Center, University of California, San Francisco, CA, USA.
| | - Chia-Ling Tu
- Endocrine Research Unit, Department of Veterans Affairs Medical Center, University of California, San Francisco, CA, USA
| | - Frederic G Jean-Alphonse
- Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Amanda Herberger
- Endocrine Research Unit, Department of Veterans Affairs Medical Center, University of California, San Francisco, CA, USA
| | - Zhiqiang Cheng
- Endocrine Research Unit, Department of Veterans Affairs Medical Center, University of California, San Francisco, CA, USA
| | - Jenna Hwong
- Endocrine Research Unit, Department of Veterans Affairs Medical Center, University of California, San Francisco, CA, USA
| | - Hanson Ho
- Endocrine Research Unit, Department of Veterans Affairs Medical Center, University of California, San Francisco, CA, USA
| | - Alfred Li
- Endocrine Research Unit, Department of Veterans Affairs Medical Center, University of California, San Francisco, CA, USA
| | - Dawei Wang
- Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Hongda Liu
- Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Alex D White
- Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Graduate Program in Molecular Pharmacology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Insoo Suh
- Department of Surgery, University of California, San Francisco, CA, USA
| | - Wen Shen
- Department of Surgery, University of California, San Francisco, CA, USA
| | - Quan-Yang Duh
- Department of Surgery, University of California, San Francisco, CA, USA
| | - Elham Khanafshar
- Department of Pathology, University of California, San Francisco, CA, USA
| | - Dolores M Shoback
- Endocrine Research Unit, Department of Veterans Affairs Medical Center, University of California, San Francisco, CA, USA
| | - Kunhong Xiao
- Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jean-Pierre Vilardaga
- Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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15
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Martín-Belmonte A, Aguado C, Alfaro-Ruíz R, Moreno-Martínez AE, de la Ossa L, Martínez-Hernández J, Buisson A, Früh S, Bettler B, Shigemoto R, Fukazawa Y, Luján R. Reduction in the neuronal surface of post and presynaptic GABA B receptors in the hippocampus in a mouse model of Alzheimer's disease. Brain Pathol 2019; 30:554-575. [PMID: 31729777 PMCID: PMC7317930 DOI: 10.1111/bpa.12802] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 11/04/2019] [Indexed: 12/25/2022] Open
Abstract
The hippocampus plays key roles in learning and memory and is a main target of Alzheimer's disease (AD), which causes progressive memory impairments. Despite numerous investigations about the processes required for the normal hippocampal functions, the neurotransmitter receptors involved in the synaptic deficits by which AD disables the hippocampus are not yet characterized. By combining histoblots, western blots, immunohistochemistry and high-resolution immunoelectron microscopic methods for GABAB receptors, this study provides a quantitative description of the expression and the subcellular localization of GABAB1 in the hippocampus in a mouse model of AD at 1, 6 and 12 months of age. Western blots and histoblots showed that the total amount of protein and the laminar expression pattern of GABAB1 were similar in APP/PS1 mice and in age-matched wild-type mice. In contrast, immunoelectron microscopic techniques showed that the subcellular localization of GABAB1 subunit did not change significantly in APP/PS1 mice at 1 month of age, was significantly reduced in the stratum lacunosum-moleculare of CA1 pyramidal cells at 6 months of age and significantly reduced at the membrane surface of CA1 pyramidal cells at 12 months of age. This reduction of plasma membrane GABAB1 was paralleled by a significant increase of the subunit at the intracellular sites. We further observed a decrease of membrane-targeted GABAB receptors in axon terminals contacting CA1 pyramidal cells. Our data demonstrate compartment- and age-dependent reduction of plasma membrane-targeted GABAB receptors in the CA1 region of the hippocampus, suggesting that this decrease might be enough to alter the GABAB -mediated synaptic transmission taking place in AD.
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Affiliation(s)
- Alejandro Martín-Belmonte
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Campus Biosanitario, C/ Almansa 14, 02008, Albacete, Spain
| | - Carolina Aguado
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Campus Biosanitario, C/ Almansa 14, 02008, Albacete, Spain
| | - Rocío Alfaro-Ruíz
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Campus Biosanitario, C/ Almansa 14, 02008, Albacete, Spain
| | - Ana Esther Moreno-Martínez
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Campus Biosanitario, C/ Almansa 14, 02008, Albacete, Spain
| | - Luis de la Ossa
- Departamento de Sistemas Informáticos, Escuela Superior de Ingeniería Informática, Universidad de Castilla-La Mancha, 02071, Albacete, Spain
| | - José Martínez-Hernández
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Campus Biosanitario, C/ Almansa 14, 02008, Albacete, Spain
| | - Alain Buisson
- Grenoble Institut des Neurosciences, Université Grenoble Alpes, BP 170, Grenoble, France
| | - Simon Früh
- Department of Biomedicine, Institute of Physiology, University of Basel, Basel, Switzerland
| | - Bernhard Bettler
- Department of Biomedicine, Institute of Physiology, University of Basel, Basel, Switzerland
| | - Ryuichi Shigemoto
- Institute of Science and Technology (IST Austria), Am Campus 1, A-3400, Klosterneuburg, Austria
| | - Yugo Fukazawa
- Division of Brain Structure and Function, Faculty of Medical Science, University of Fukui, Fukui, Japan.,Life Science Innovation Center, University of Fukui, Fukui, Japan.,Research Center for Child Mental Development, Faculty of Medical Science, University of Fukui, Fukui, Japan
| | - Rafael Luján
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Campus Biosanitario, C/ Almansa 14, 02008, Albacete, Spain
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16
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Nagai J, Rajbhandari AK, Gangwani MR, Hachisuka A, Coppola G, Masmanidis SC, Fanselow MS, Khakh BS. Hyperactivity with Disrupted Attention by Activation of an Astrocyte Synaptogenic Cue. Cell 2019; 177:1280-1292.e20. [PMID: 31031006 PMCID: PMC6526045 DOI: 10.1016/j.cell.2019.03.019] [Citation(s) in RCA: 185] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Revised: 02/08/2019] [Accepted: 03/07/2019] [Indexed: 11/19/2022]
Abstract
Hyperactivity and disturbances of attention are common behavioral disorders whose underlying cellular and neural circuit causes are not understood. We report the discovery that striatal astrocytes drive such phenotypes through a hitherto unknown synaptic mechanism. We found that striatal medium spiny neurons (MSNs) triggered astrocyte signaling via γ-aminobutyric acid B (GABAB) receptors. Selective chemogenetic activation of this pathway in striatal astrocytes in vivo resulted in acute behavioral hyperactivity and disrupted attention. Such responses also resulted in upregulation of the synaptogenic cue thrombospondin-1 (TSP1) in astrocytes, increased excitatory synapses, enhanced corticostriatal synaptic transmission, and increased MSN action potential firing in vivo. All of these changes were reversed by blocking TSP1 effects. Our data identify a form of bidirectional neuron-astrocyte communication and demonstrate that acute reactivation of a single latent astrocyte synaptogenic cue alters striatal circuits controlling behavior, revealing astrocytes and the TSP1 pathway as therapeutic targets in hyperactivity, attention deficit, and related psychiatric disorders.
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Affiliation(s)
- Jun Nagai
- Department of Physiology, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Abha K Rajbhandari
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Mohitkumar R Gangwani
- Department of Physiology, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Ayaka Hachisuka
- Department of Neurobiology, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Giovanni Coppola
- Department of Neurology, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA; Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA; Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Sotiris C Masmanidis
- Department of Neurobiology, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Michael S Fanselow
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA; Department of Psychology, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Baljit S Khakh
- Department of Physiology, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA; Department of Neurobiology, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA.
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17
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Monitoring Interneuron-Astrocyte Signaling and Its Consequences on Synaptic Transmission. Methods Mol Biol 2019; 1938:117-129. [PMID: 30617977 DOI: 10.1007/978-1-4939-9068-9_9] [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: 02/23/2023]
Abstract
Whole-cell patch clamp allows the characterization of synaptic transmission in neurons. It is possible to manipulate astrocytic activity and record how these glial cells affect neuronal networks. Here we describe the methodology to monitor the endogenously activation of astrocytes by inhibitory synaptic activity. Afterward, such glial activation will let us study the consequences of interneuron-astrocyte signaling on excitatory neurotransmission at hippocampal synapses.
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18
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Prüss H, Kirmse K. Pathogenic role of autoantibodies against inhibitory synapses. Brain Res 2018; 1701:146-152. [DOI: 10.1016/j.brainres.2018.09.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 08/20/2018] [Accepted: 09/07/2018] [Indexed: 12/13/2022]
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19
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Parvalbumin-Interneuron Output Synapses Show Spike-Timing-Dependent Plasticity that Contributes to Auditory Map Remodeling. Neuron 2018; 99:720-735.e6. [DOI: 10.1016/j.neuron.2018.07.018] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 05/16/2018] [Accepted: 07/10/2018] [Indexed: 11/19/2022]
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20
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Faroni A, Melfi S, Castelnovo LF, Bonalume V, Colleoni D, Magni P, Araúzo-Bravo MJ, Reinbold R, Magnaghi V. GABA-B1 Receptor-Null Schwann Cells Exhibit Compromised In Vitro Myelination. Mol Neurobiol 2018; 56:1461-1474. [PMID: 29948947 DOI: 10.1007/s12035-018-1158-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 05/28/2018] [Indexed: 12/11/2022]
Abstract
GABA-B receptors are important for Schwann cell (SC) commitment to a non-myelinating phenotype during development. However, the P0-GABA-B1fl/fl conditional knockout mice, lacking the GABA-B1 receptor specifically in SCs, also presented axon modifications, suggesting SC non-autonomous effects through the neuronal compartment. In this in vitro study, we evaluated whether the specific deletion of the GABA-B1 receptor in SCs may induce autonomous or non-autonomous cross-changes in sensory dorsal root ganglia (DRG) neurons. To this end, we performed an in vitro biomolecular and transcriptomic analysis of SC and DRG neuron primary cultures from P0-GABA-B1fl/fl mice. We found that cells from conditional P0-GABA-B1fl/fl mice exhibited proliferative, migratory and myelinating alterations. Moreover, we found transcriptomic changes in novel molecules that are involved in peripheral neuron-SC interaction.
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Affiliation(s)
- Alessandro Faroni
- Blond McIndoe Laboratories, Division of Cell Matrix Biology and Regenerative Medicine, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Simona Melfi
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti 9, 20133, Milan, Italy
| | - Luca Franco Castelnovo
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti 9, 20133, Milan, Italy
| | - Veronica Bonalume
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti 9, 20133, Milan, Italy
| | - Deborah Colleoni
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti 9, 20133, Milan, Italy
| | - Paolo Magni
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti 9, 20133, Milan, Italy
| | - Marcos J Araúzo-Bravo
- Computational Biology and Systems Biomedicine, Biodonostia Health Research Institute, San Sebastián, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao, Spain
| | - Rolland Reinbold
- Institute of Biomedical Technologies, National Research Council, Milan, Italy
| | - Valerio Magnaghi
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via G. Balzaretti 9, 20133, Milan, Italy.
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21
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Jahn HM, Kasakow CV, Helfer A, Michely J, Verkhratsky A, Maurer HH, Scheller A, Kirchhoff F. Refined protocols of tamoxifen injection for inducible DNA recombination in mouse astroglia. Sci Rep 2018; 8:5913. [PMID: 29651133 PMCID: PMC5897555 DOI: 10.1038/s41598-018-24085-9] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 03/27/2018] [Indexed: 01/26/2023] Open
Abstract
Inducible DNA recombination of floxed alleles in vivo by liver metabolites of tamoxifen (TAM) is an important tool to study gene functions. Here, we describe protocols for optimal DNA recombination in astrocytes, based on the GLAST-CreERT2/loxP system. In addition, we demonstrate that quantification of genomic recombination allows to determine the proportion of cell types in various brain regions. We analyzed the presence and clearance of TAM and its metabolites (N-desmethyl-tamoxifen, 4-hydroxytamoxifen and endoxifen) in brain and serum of mice by liquid chromatographic-high resolution-tandem mass spectrometry (LC-HR-MS/MS) and assessed optimal injection protocols by quantitative RT-PCR of several floxed target genes (p2ry1, gria1, gabbr1 and Rosa26-tdTomato locus). Maximal recombination could be achieved in cortex and cerebellum by single daily injections for five and three consecutive days, respectively. Furthermore, quantifying the loss of floxed alleles predicted the percentage of GLAST-positive cells (astroglia) per brain region. We found that astrocytes contributed 20 to 30% of the total cell number in cortex, hippocampus, brainstem and optic nerve, while in the cerebellum Bergmann glia, velate astrocytes and white matter astrocytes accounted only for 8% of all cells.
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Affiliation(s)
- Hannah M Jahn
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, 66421 Homburg, Germany
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester M13 9PL, UK
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University Hospital of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Carmen V Kasakow
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, 66421 Homburg, Germany
| | - Andreas Helfer
- Department of Experimental and Clinical Toxicology, University of Saarland, 66421, Homburg, Germany
| | - Julian Michely
- Department of Experimental and Clinical Toxicology, University of Saarland, 66421, Homburg, Germany
| | - Alexei Verkhratsky
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester M13 9PL, UK
| | - Hans H Maurer
- Department of Experimental and Clinical Toxicology, University of Saarland, 66421, Homburg, Germany
| | - Anja Scheller
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, 66421 Homburg, Germany
| | - Frank Kirchhoff
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, 66421 Homburg, Germany.
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22
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Covelo A, Araque A. Neuronal activity determines distinct gliotransmitter release from a single astrocyte. eLife 2018; 7:32237. [PMID: 29380725 PMCID: PMC5790377 DOI: 10.7554/elife.32237] [Citation(s) in RCA: 140] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 01/23/2018] [Indexed: 12/11/2022] Open
Abstract
Accumulating evidence indicates that astrocytes are actively involved in brain function by regulating synaptic activity and plasticity. Different gliotransmitters, such as glutamate, ATP, GABA or D-serine, released form astrocytes have been shown to induce different forms of synaptic regulation. However, whether a single astrocyte may release different gliotransmitters is unknown. Here we show that mouse hippocampal astrocytes activated by endogenous (neuron-released endocannabinoids or GABA) or exogenous (single astrocyte Ca2+ uncaging) stimuli modulate putative single CA3-CA1 hippocampal synapses. The astrocyte-mediated synaptic modulation was biphasic and consisted of an initial glutamate-mediated potentiation followed by a purinergic-mediated depression of neurotransmitter release. The temporal dynamic properties of this biphasic synaptic regulation depended on the firing frequency and duration of the neuronal activity that stimulated astrocytes. Present results indicate that single astrocytes can decode neuronal activity and, in response, release distinct gliotransmitters to differentially regulate neurotransmission at putative single synapses.
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Affiliation(s)
- Ana Covelo
- Department of Neuroscience, University of Minnesota, Minneapolis, United States
| | - Alfonso Araque
- Department of Neuroscience, University of Minnesota, Minneapolis, United States
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23
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GABAB Receptors Tune Cortical Feedback to the Olfactory Bulb. J Neurosci 2017; 36:8289-304. [PMID: 27511004 DOI: 10.1523/jneurosci.3823-15.2016] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 06/09/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Sensory perception emerges from the confluence of sensory inputs that encode the composition of external environment and top-down feedback that conveys information from higher brain centers. In olfaction, sensory input activity is initially processed in the olfactory bulb (OB), serving as the first central relay before being transferred to the olfactory cortex. In addition, the OB receives dense connectivity from feedback projections, so the OB has the capacity to implement a wide array of sensory neuronal computation. However, little is known about the impact and the regulation of this cortical feedback. Here, we describe a novel mechanism to gate glutamatergic feedback selectively from the anterior olfactory cortex (AOC) to the OB. Combining in vitro and in vivo electrophysiological recordings, optogenetics, and fiber-photometry-based calcium imaging applied to wild-type and conditional transgenic mice, we explore the functional consequences of circuit-specific GABA type-B receptor (GABABR) manipulation. We found that activation of presynaptic GABABRs specifically depresses synaptic transmission from the AOC to OB inhibitory interneurons, but spares direct excitation to principal neurons. As a consequence, feedforward inhibition of spontaneous and odor-evoked activity of principal neurons is diminished. We also show that tunable cortico-bulbar feedback is critical for generating beta, but not gamma, OB oscillations. Together, these results show that GABABRs on cortico-bulbar afferents gate excitatory transmission in a target-specific manner and thus shape how the OB integrates sensory inputs and top-down information. SIGNIFICANCE STATEMENT The olfactory bulb (OB) receives top-down inputs from the olfactory cortex that produce direct excitation and feedforward inhibition onto mitral and tufted cells, the principal neurons. The functional role of this feedback and the mechanisms regulating the balance of feedback excitation and inhibition remain unknown. We found that GABAB receptors are expressed in cortico-bulbar axons that synapse on granule cells and receptor activation reduces the feedforward inhibition of spontaneous and odor-driven mitral and tufted cells' firing activity. In contrast, direct excitatory inputs to these principal neurons remain unchanged. This study demonstrates that activation of GABAB receptors biases the excitation/inhibition balance provided by cortical inputs to the OB, leading to profound effects on early stages of sensory information processing.
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24
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Edwards NJ, Tejeda HA, Pignatelli M, Zhang S, McDevitt RA, Wu J, Bass CE, Bettler B, Morales M, Bonci A. Circuit specificity in the inhibitory architecture of the VTA regulates cocaine-induced behavior. Nat Neurosci 2017; 20:438-448. [DOI: 10.1038/nn.4482] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 12/20/2016] [Indexed: 12/17/2022]
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25
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Perea G, Gómez R, Mederos S, Covelo A, Ballesteros JJ, Schlosser L, Hernández-Vivanco A, Martín-Fernández M, Quintana R, Rayan A, Díez A, Fuenzalida M, Agarwal A, Bergles DE, Bettler B, Manahan-Vaughan D, Martín ED, Kirchhoff F, Araque A. Activity-dependent switch of GABAergic inhibition into glutamatergic excitation in astrocyte-neuron networks. eLife 2016; 5. [PMID: 28012274 PMCID: PMC5231406 DOI: 10.7554/elife.20362] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 12/23/2016] [Indexed: 12/28/2022] Open
Abstract
Interneurons are critical for proper neural network function and can activate Ca2+ signaling in astrocytes. However, the impact of the interneuron-astrocyte signaling into neuronal network operation remains unknown. Using the simplest hippocampal Astrocyte-Neuron network, i.e., GABAergic interneuron, pyramidal neuron, single CA3-CA1 glutamatergic synapse, and astrocytes, we found that interneuron-astrocyte signaling dynamically affected excitatory neurotransmission in an activity- and time-dependent manner, and determined the sign (inhibition vs potentiation) of the GABA-mediated effects. While synaptic inhibition was mediated by GABAA receptors, potentiation involved astrocyte GABAB receptors, astrocytic glutamate release, and presynaptic metabotropic glutamate receptors. Using conditional astrocyte-specific GABAB receptor (Gabbr1) knockout mice, we confirmed the glial source of the interneuron-induced potentiation, and demonstrated the involvement of astrocytes in hippocampal theta and gamma oscillations in vivo. Therefore, astrocytes decode interneuron activity and transform inhibitory into excitatory signals, contributing to the emergence of novel network properties resulting from the interneuron-astrocyte interplay. DOI:http://dx.doi.org/10.7554/eLife.20362.001
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Affiliation(s)
- Gertrudis Perea
- Consejo Superior de Investigaciones Científicas, Instituto Cajal, Madrid, Spain
| | - Ricardo Gómez
- Consejo Superior de Investigaciones Científicas, Instituto Cajal, Madrid, Spain.,Cellular and Systems Neurobiology, Systems Biology Program, Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Sara Mederos
- Consejo Superior de Investigaciones Científicas, Instituto Cajal, Madrid, Spain
| | - Ana Covelo
- Department of Neuroscience, University of Minnesota, Minneapolis, United States
| | - Jesús J Ballesteros
- Albacete Science and Technology Park, Institute for Research in Neurological Disabilities, University of Castilla-La Mancha, Albacete, Spain.,Department of Neurophysiology, Faculty of Medicine, Ruhr University Bochum, Bochum, Germany
| | - Laura Schlosser
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine, University of Saarland, Homburg, Germany
| | | | | | - Ruth Quintana
- Department of Neuroscience, University of Minnesota, Minneapolis, United States
| | - Abdelrahman Rayan
- Department of Neurophysiology, Faculty of Medicine, Ruhr University Bochum, Bochum, Germany
| | - Adolfo Díez
- Department of Neuroscience, University of Minnesota, Minneapolis, United States
| | - Marco Fuenzalida
- Center of Neurobiology and Brain Plasticity, Institute of Physiology, Faculty of Science, Universidad de Valparaíso, Valparaiso, Chile
| | - Amit Agarwal
- Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, United States
| | - Dwight E Bergles
- Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, United States
| | - Bernhard Bettler
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Denise Manahan-Vaughan
- Department of Neurophysiology, Faculty of Medicine, Ruhr University Bochum, Bochum, Germany
| | - Eduardo D Martín
- Albacete Science and Technology Park, Institute for Research in Neurological Disabilities, University of Castilla-La Mancha, Albacete, Spain
| | - Frank Kirchhoff
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine, University of Saarland, Homburg, Germany
| | - Alfonso Araque
- Department of Neuroscience, University of Minnesota, Minneapolis, United States
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26
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Glutamate input in the dorsal raphe nucleus as a determinant of escalated aggression in male mice. J Neurosci 2015; 35:6452-63. [PMID: 25904796 DOI: 10.1523/jneurosci.2450-14.2015] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Although the dorsal raphe nucleus (DRN) has long been linked to neural control of aggression, little is known about the regulatory influences of the DRN when an animal engages in either adaptive species-typical aggressive behavior or escalated aggression. Therefore it is important to explore which neurotransmitter inputs into the DRN determine the escalation of aggression in male mice. Previously, we observed that microinjection of the GABAB receptor agonist baclofen into the DRN escalates aggressive behavior in male mice. Here, we used a serotonin (5-HT) neuron-specific GABAB receptor knock-out mouse to demonstrate that baclofen acts on nonserotonergic neurons to escalate aggression. Intra-DRN baclofen administration increased glutamate release, but did not alter GABA release, within the DRN. Microinjection of l-glutamate into the DRN escalated dose-dependently attack bites toward an intruder. In vivo microdialysis showed that glutamate release increased in the DRN during an aggressive encounter, and the level of glutamate was further increased when the animal was engaged in escalated aggressive behavior after social instigation. Finally, 5-HT release was increased within the DRN and also in the medial prefrontal cortex when animals were provoked by social instigation, and during escalated aggression after social instigation, but this increase in 5-HT release was not observed when animals were engaged in species-typical aggression. In summary, glutamate input into the DRN is enhanced during escalated aggression, which causes a phasic increase of 5-HT release from the DRN 5-HT neurons.
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27
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Hanack C, Moroni M, Lima WC, Wende H, Kirchner M, Adelfinger L, Schrenk-Siemens K, Tappe-Theodor A, Wetzel C, Kuich PH, Gassmann M, Roggenkamp D, Bettler B, Lewin GR, Selbach M, Siemens J. GABA blocks pathological but not acute TRPV1 pain signals. Cell 2015; 160:759-770. [PMID: 25679765 DOI: 10.1016/j.cell.2015.01.022] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 11/16/2014] [Accepted: 01/06/2015] [Indexed: 01/01/2023]
Abstract
Sensitization of the capsaicin receptor TRPV1 is central to the initiation of pathological forms of pain, and multiple signaling cascades are known to enhance TRPV1 activity under inflammatory conditions. How might detrimental escalation of TRPV1 activity be counteracted? Using a genetic-proteomic approach, we identify the GABAB1 receptor subunit as bona fide inhibitor of TRPV1 sensitization in the context of diverse inflammatory settings. We find that the endogenous GABAB agonist, GABA, is released from nociceptive nerve terminals, suggesting an autocrine feedback mechanism limiting TRPV1 sensitization. The effect of GABAB on TRPV1 is independent of canonical G protein signaling and rather relies on close juxtaposition of the GABAB1 receptor subunit and TRPV1. Activating the GABAB1 receptor subunit does not attenuate normal functioning of the capsaicin receptor but exclusively reverts its sensitized state. Thus, harnessing this mechanism for anti-pain therapy may prevent adverse effects associated with currently available TRPV1 blockers.
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Affiliation(s)
- Christina Hanack
- Department of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany; Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
| | - Mirko Moroni
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
| | - Wanessa C Lima
- Department of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Hagen Wende
- Department of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Marieluise Kirchner
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
| | - Lisa Adelfinger
- Department of Biomedicine, University of Basel, CH-4056 Basel, Switzerland
| | - Katrin Schrenk-Siemens
- Department of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Anke Tappe-Theodor
- Department of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Christiane Wetzel
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
| | - P Henning Kuich
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
| | - Martin Gassmann
- Department of Biomedicine, University of Basel, CH-4056 Basel, Switzerland
| | - Dennis Roggenkamp
- Beiersdorf AG, Research & Development, Unnastrasse 48, 20245 Hamburg, Germany
| | - Bernhard Bettler
- Department of Biomedicine, University of Basel, CH-4056 Basel, Switzerland
| | - Gary R Lewin
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
| | - Matthias Selbach
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
| | - Jan Siemens
- Department of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany.
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28
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Kim JY, Ho H, Kim N, Liu J, Tu CL, Yenari MA, Chang W. Calcium-sensing receptor (CaSR) as a novel target for ischemic neuroprotection. Ann Clin Transl Neurol 2014; 1:851-66. [PMID: 25540800 PMCID: PMC4265057 DOI: 10.1002/acn3.118] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 08/14/2014] [Accepted: 08/15/2014] [Indexed: 01/04/2023] Open
Abstract
Object Ischemic brain injury is the leading cause for death and long-term disability in patients who suffer cardiac arrest and embolic stroke. Excitotoxicity and subsequent Ca2+-overload lead to ischemic neuron death. We explore a novel mechanism concerning the role of the excitatory extracellular calcium-sensing receptor (CaSR) in the induction of ischemic brain injury. Method Mice were exposed to forebrain ischemia and the actions of CaSR were determined after its genes were ablated specifically in hippocampal neurons or its activities were inhibited pharmacologically. Since the CaSR forms a heteromeric complex with the inhibitory type B γ-aminobutyric acid receptor 1 (GABABR1), we compared neuronal responses to ischemia in mice deficient in CaSR, GABABR1, or both, and in mice injected locally or systemically with a specific CaSR antagonist (or calcilytic) in the presence or absence of a GABABR1 agonist (baclofen). Results Both global and focal brain ischemia led to CaSR overexpression and GABABR1 downregulation in injured neurons. Genetic ablation of Casr genes or blocking CaSR activities by calcilytics rendered robust neuroprotection and preserved learning and memory functions in ischemic mice, partly by restoring GABABR1 expression. Concurrent ablation of Gabbr1 gene blocked the neuroprotection caused by the Casr gene knockout. Coinjection of calcilytics with baclofen synergistically enhanced neuroprotection. This combined therapy remained robust when given 6 h after ischemia. Interpretation Our study demonstrates a novel receptor interaction, which contributes to ischemic neuron death through CaSR upregulation and GABABR1 downregulation, and feasibility of neuroprotection by concurrently targeting these two receptors.
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Affiliation(s)
- Jong Youl Kim
- Endocrine Unit, University of California San Francisco and Veterans Affairs Medical Center San Francisco, California, 94121 ; Department of Neurology, University of California San Francisco and Veterans Affairs Medical Center San Francisco, California, 94121
| | - Hanson Ho
- Endocrine Unit, University of California San Francisco and Veterans Affairs Medical Center San Francisco, California, 94121
| | - Nuri Kim
- Department of Neurology, University of California San Francisco and Veterans Affairs Medical Center San Francisco, California, 94121
| | - Jialing Liu
- Neurological Surgery, University of California San Francisco and Veterans Affairs Medical Center San Francisco, California, 94121
| | - Chia-Ling Tu
- Endocrine Unit, University of California San Francisco and Veterans Affairs Medical Center San Francisco, California, 94121
| | - Midori A Yenari
- Department of Neurology, University of California San Francisco and Veterans Affairs Medical Center San Francisco, California, 94121
| | - Wenhan Chang
- Endocrine Unit, University of California San Francisco and Veterans Affairs Medical Center San Francisco, California, 94121
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29
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Faroni A, Castelnovo LF, Procacci P, Caffino L, Fumagalli F, Melfi S, Gambarotta G, Bettler B, Wrabetz L, Magnaghi V. Deletion of GABA-B receptor in Schwann cells regulates remak bundles and small nociceptive C-fibers. Glia 2014; 62:548-65. [PMID: 24474699 DOI: 10.1002/glia.22625] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 12/16/2013] [Accepted: 12/19/2013] [Indexed: 12/16/2023]
Abstract
The mechanisms regulating the differentiation into non-myelinating Schwann cells is not completely understood. Recent evidence indicates that GABA-B receptors may regulate myelination and nociception in the peripheral nervous system. GABA-B receptor total knock-out mice exhibit morphological and molecular changes in peripheral myelin. The number of small myelinated fibers is higher and associated with altered pain sensitivity. Herein, we analyzed whether these changes may be produced by a specific deletion of GABA-B receptors in Schwann cells. The conditional mice (P0-GABA-B1(fl/fl)) show a morphological phenotype characterized by a peculiar increase in the number of small unmyelinated fibers and Remak bundles, including nociceptive C-fibers. The P0-GABA-B1(fl/fl) mice are hyperalgesic and allodynic. In these mice, the morphological and behavioral changes are associated with a downregulation of neuregulin 1 expression in nerves. Our findings suggest that the altered pain sensitivity derives from a Schwann cell-specific loss of GABA-B receptor functions, pointing to a role for GABA-B receptors in the regulation of Schwann cell maturation towards the non-myelinating phenotype.
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Affiliation(s)
- Alessandro Faroni
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Balzaretti 9, 20133, Milan, Italy; Blond McIndoe Laboratories, The University of Manchester, Institute of Inflammation and Repair, M13 9PT, Manchester, United Kingdom
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GABA type B receptor signaling in proopiomelanocortin neurons protects against obesity, insulin resistance, and hypothalamic inflammation in male mice on a high-fat diet. J Neurosci 2013; 33:17166-73. [PMID: 24155320 DOI: 10.1523/jneurosci.0897-13.2013] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
There is evidence suggesting that the GABA system in the arcuate nucleus, where orexigenic neuropeptide Y and agouti-related peptide as well as anorexigenic proopiomelanocortin (POMC) are expressed, plays an important role in energy balance. In this study, we generated POMC-specific GABAB receptor-deficient [knock-out (KO)] mice. Male KO mice on a high-fat diet (HFD) showed mild increases in body weight (BW) at the age of 9 weeks compared to wild-type (WT) mice, and the differences remained significant until 16 weeks old. However, there was no difference in BW in females between genotypes. While food intake was similar between genotypes, oxygen consumption was significantly decreased in the male KO mice. The insulin tolerance test revealed that the male KO mice were less insulin sensitive compared to WT mice at the age of 8 weeks, when there was no significant difference in BW between genotypes. Despite increased BW, POMC mRNA expression in the arcuate nucleus was significantly decreased in the KO mice compared to WT mice at the age of 16 weeks. Furthermore, the expression of TNFα as well as IL-6, proinflammatory markers in the hypothalamus, was significantly increased in the KO mice on a HFD compared to WT mice. This demonstrates that the deletion of GABAB receptors in POMC neurons in the male mice on a HFD results in obesity, insulin resistance, and hypothalamic inflammation. Furthermore, the decreased POMC expression in the obese KO mice suggests that the regulation of POMC expression through GABAB receptors is essential for proper energy balance.
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Giachino C, Barz M, Tchorz JS, Tome M, Gassmann M, Bischofberger J, Bettler B, Taylor V. GABA suppresses neurogenesis in the adult hippocampus through GABAB receptors. Development 2013; 141:83-90. [PMID: 24284211 DOI: 10.1242/dev.102608] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Adult neurogenesis is tightly regulated through the interaction of neural stem/progenitor cells (NSCs) with their niche. Neurotransmitters, including GABA activation of GABAA receptor ion channels, are important niche signals. We show that adult mouse hippocampal NSCs and their progeny express metabotropic GABAB receptors. Pharmacological inhibition of GABAB receptors stimulated NSC proliferation and genetic deletion of GABAB1 receptor subunits increased NSC proliferation and differentiation of neuroblasts in vivo. Cell-specific conditional deletion of GABAB receptors supports a cell-autonomous role in newly generated cells. Our data indicate that signaling through GABAB receptors is an inhibitor of adult neurogenesis.
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Affiliation(s)
- Claudio Giachino
- Embryology and Stem Cell Biology, Department of Biomedicine, University of Basel, Mattenstrasse 28, CH-4058 Basel, Switzerland
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Bony G, Szczurkowska J, Tamagno I, Shelly M, Contestabile A, Cancedda L. Non-hyperpolarizing GABAB receptor activation regulates neuronal migration and neurite growth and specification by cAMP/LKB1. Nat Commun 2013; 4:1800. [PMID: 23653212 DOI: 10.1038/ncomms2820] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 03/28/2013] [Indexed: 12/28/2022] Open
Abstract
γ-Aminobutyric acid is the principal inhibitory neurotransmitter in adults, acting through ionotropic chloride-permeable GABAA receptors (GABAARs), and metabotropic GABABRs coupled to calcium or potassium channels, and cyclic AMP signalling. During early development, γ-aminobutyric acid is the main neurotransmitter and is not hyperpolarizing, as GABAAR activation is depolarizing while GABABRs lack coupling to potassium channels. Despite extensive knowledge on GABAARs as key factors in neuronal development, the role of GABABRs remains unclear. Here we address GABABR function during rat cortical development by in utero knockdown (short interfering RNA) of GABABR in pyramidal-neuron progenitors. GABABR short interfering RNA impairs neuronal migration and axon/dendrite morphological maturation by disrupting cyclic AMP signalling. Furthermore, GABABR activation reduces cyclic AMP-dependent phosphorylation of LKB1, a kinase involved in neuronal polarization, and rescues LKB1 overexpression-induced defects in cortical development. Thus, non-hyperpolarizing activation of GABABRs during development promotes neuronal migration and morphological maturation by cyclic AMP/LKB1 signalling.
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Affiliation(s)
- Guillaume Bony
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Via Morego, 30 Genoa 16163, Italy
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Gaiarsa JL, Porcher C. Emerging neurotrophic role of GABAB receptors in neuronal circuit development. Front Cell Neurosci 2013; 7:206. [PMID: 24282395 PMCID: PMC3824957 DOI: 10.3389/fncel.2013.00206] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 10/18/2013] [Indexed: 12/22/2022] Open
Abstract
The proper development of highly organized structures in the central nervous system is a complex process during which key events – neurogenesis, migration, growth, differentiation, and synaptogenesis – have to take place in an appropriate manner to create functional neuronal networks. It is now well established that GABA, the main inhibitory neurotransmitter in the adult mammalian brain, plays more than a classical inhibitory role and can function as an important developmental signal early in life. GABA binds to chloride-permeable ionotropic GABAA receptors and to G-protein-coupled GABAB receptors (GABAB-Rs). Although most of the trophic actions of GABA have been attributed to the activation of GABAA receptors, recent advances show that GABAB-Rs also regulate fundamental steps of network development. This review summarizes some of the recent progress about the neurotrophic role of GABAB-Rs to neuronal development.
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Affiliation(s)
- Jean-Luc Gaiarsa
- Institut National de la Santé et de la Recherche Médicale U-901 Marseille, France ; Aix-Marseille Université, UMR S901 Marseille, France ; Institut de Neurobiologie de la Méditerranée Marseille, France
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GABAergic inhibition of histaminergic neurons regulates active waking but not the sleep-wake switch or propofol-induced loss of consciousness. J Neurosci 2012; 32:13062-75. [PMID: 22993424 DOI: 10.1523/jneurosci.2931-12.2012] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The activity of histaminergic neurons in the tuberomammillary nucleus (TMN) of the hypothalamus correlates with an animal's behavioral state and maintains arousal. We examined how GABAergic inputs onto histaminergic neurons regulate this behavior. A prominent hypothesis, the "flip-flop" model, predicts that increased and sustained GABAergic drive onto these cells promotes sleep. Similarly, because of the histaminergic neurons' key hub-like place in the arousal circuitry, it has also been suggested that anesthetics such as propofol induce loss of consciousness by acting primarily at histaminergic neurons. We tested both these hypotheses in mice by genetically removing ionotropic GABA(A) or metabotropic GABA(B) receptors from histidine decarboxylase-expressing neurons. At the cellular level, histaminergic neurons deficient in synaptic GABA(A) receptors were significantly more excitable and were insensitive to the anesthetic propofol. At the behavioral level, EEG profiles were recorded in nontethered mice over 24 h. Surprisingly, GABAergic transmission onto histaminergic neurons had no effect in regulating the natural sleep-wake cycle and, in the case of GABA(A) receptors, for propofol-induced loss of righting reflex. The latter finding makes it unlikely that the histaminergic TMN has a central role in anesthesia. GABA(B) receptors on histaminergic neurons were dispensable for all behaviors examined. Synaptic inhibition of histaminergic cells by GABA(A) receptors, however, was essential for habituation to a novel environment.
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Fukui M, Ozawa S, Nakamichi N, Nakazato R, Takarada T, Yoneda Y. Gradual downregulation of protein expression of the partner GABA(B)R2 subunit during postnatal brain development in mice defective of GABA(B)R1 subunit. J Pharmacol Sci 2010; 115:45-55. [PMID: 21160134 DOI: 10.1254/jphs.10254fp] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
We have previously shown the functional expression of GABA(B) receptors (GABA(B)R) composed of GABA(B)R1 and GABA(B)R2 subunits with ability to promote proliferation and neuronal differentiation in cultured neural progenitor cells (NPC) isolated from embryonic mouse brains. In this study, we evaluated postnatal changes in the expression profiles of different markers for progenitor, neuronal, astroglial, and microglial cells in brains of GABA(B)R1-null mice. Consistent with undifferentiated murine NPC cultured with epidermal growth factor, a significant and selective decrease was seen in mRNA expression of the proneural gene Mash1 in brains of GABA(B)R1-null mice at 1 day after birth. The expression of several NPC marker proteins was similarly decreased in brains of both wild-type and GABA(B)R1-null mice from 1 to 7 days after birth, while slight changes were induced in both mRNA and proteins for neuronal, astroglial, and microglial markers between wild-type and GABA(B)R1-null mouse brains within this developmental stage. In particular discrete brain structures of adult GABA(B)R1-null mice at 56 days after birth, a significant decrease was seen in neuronal marker protein levels along with a significant increase in both astroglial and microglial marker protein expression. Although no significant difference was found in mRNA expression of the partner GABA(B)R2 subunit between wild-type and GABA(B)R1-null mouse brains, GABA(B)R2 subunit protein levels were gradually declined during postnatal development within 56 days after birth in GABA(B)R1-null mouse brains. These results suggest that GABA(B)R2 protein levels are closely correlated with the partner subunit GABA(B)R1 protein levels in mouse brains during postnatal development in vivo.
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Affiliation(s)
- Masaki Fukui
- Kanazawa University Graduate School of Natural Science and Technology, Kanazawa, Japan
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Gangadharan V, Agarwal N, Brugger S, Tegeder I, Bettler B, Kuner R, Kurejova M. Conditional gene deletion reveals functional redundancy of GABAB receptors in peripheral nociceptors in vivo. Mol Pain 2009; 5:68. [PMID: 19925671 PMCID: PMC2785766 DOI: 10.1186/1744-8069-5-68] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Accepted: 11/19/2009] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND gamma-aminobutyric acid (GABA) is an important inhibitory neurotransmitter which mainly mediates its effects on neurons via ionotropic (GABA(A)) and metabotropic (GABA(B)) receptors. GABA(B) receptors are widely expressed in the central and the peripheral nervous system. Although there is evidence for a key function of GABA(B) receptors in the modulation of pain, the relative contribution of peripherally- versus centrally-expressed GABA(B) receptors is unclear. RESULTS In order to elucidate the functional relevance of GABA(B) receptors expressed in peripheral nociceptive neurons in pain modulation we generated and analyzed conditional mouse mutants lacking functional GABA(B1) subunit specifically in nociceptors, preserving expression in the spinal cord and brain (SNS-GABA(B1)-/- mice). Lack of the GABA(B1) subunit precludes the assembly of functional GABA(B) receptor. We analyzed SNS-GABA(B1)-/- mice and their control littermates in several models of acute and neuropathic pain. Electrophysiological studies on peripheral afferents revealed higher firing frequencies in SNS-GABA(B1)-/- mice compared to corresponding control littermates. However no differences were seen in basal nociceptive sensitivity between these groups. The development of neuropathic and chronic inflammatory pain was similar across the two genotypes. The duration of nocifensive responses evoked by intraplantar formalin injection was prolonged in the SNS-GABAB(1)-/- animals as compared to their control littermates. Pharmacological experiments revealed that systemic baclofen-induced inhibition of formalin-induced nociceptive behaviors was not dependent upon GABA(B1) expression in nociceptors. CONCLUSION This study addressed contribution of GABA(B) receptors expressed on primary afferent nociceptive fibers to the modulation of pain. We observed that neither the development of acute and chronic pain nor the analgesic effects of a systematically-delivered GABA(B) agonist was significantly changed upon a specific deletion of GABA(B) receptors from peripheral nociceptive neurons in vivo. This lets us conclude that GABA(B) receptors in the peripheral nervous system play a less important role than those in the central nervous system in the regulation of pain.
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Affiliation(s)
- Vijayan Gangadharan
- Pharmacology Institute, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany.
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Selective loss of GABA(B) receptors in orexin-producing neurons results in disrupted sleep/wakefulness architecture. Proc Natl Acad Sci U S A 2009; 106:4459-64. [PMID: 19246384 DOI: 10.1073/pnas.0811126106] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Hypothalamic neurons that contain the neuropeptide orexin (hypocretin) play important roles in the regulation of sleep/wake. Here we analyze the in vivo and in vitro phenotype of mice lacking the GABA(B1) gene specifically in orexin neurons (oxGKO mice) and demonstrate that GABA(B) receptors on orexin neurons are essential in stabilizing and consolidating sleep/wake states. In oxGKO brain slices, we show that the absence of GABA(B) receptors decreases the sensitivity of orexin neurons to both excitatory and inhibitory inputs because of augmented GABA(A)-mediated inhibition that increases the membrane conductance and shunts postsynaptic currents in these neurons. This increase in GABA(A)-mediated inhibitory tone is apparently the result of an orexin receptor type 1-mediated activation of local GABAergic interneurons that project back onto orexin neurons. oxGKO mice exhibit severe fragmentation of sleep/wake states during both the light and dark periods, without showing an abnormality in total sleep time or signs of cataplexy. Thus, GABA(B) receptors on orexin neurons are crucial in the appropriate control of the orexinergic tone through sleep/wake states, thereby stabilizing the state switching mechanisms.
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38
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Maison SF, Casanova E, Holstein GR, Bettler B, Liberman MC. Loss of GABAB receptors in cochlear neurons: threshold elevation suggests modulation of outer hair cell function by type II afferent fibers. J Assoc Res Otolaryngol 2008; 10:50-63. [PMID: 18925381 DOI: 10.1007/s10162-008-0138-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2008] [Accepted: 09/02/2008] [Indexed: 01/25/2023] Open
Abstract
Despite pharmacological and immunohistochemical evidence for GABA as a neurotransmitter in the olivocochlear efferent bundle, a clear functional role of GABA in the inner ear has not emerged. To explore the role of metabotropic GABA(B) receptors, we characterized the cochlear phenotype of mice with targeted deletion of the GABA(B1) subunit and determined its tissue localization using a mouse line expressing a GFP-tagged GABA(B1) subunit under the endogenous promoter. Immunostaining revealed GABA(B1) expression in both type I and type II ganglion cells and in their synaptic terminals under inner and outer hair cells, respectively. No GABA(B1) expression was observed in hair cells. Mean cochlear thresholds, measured via both auditory brainstem responses and distortion product otoacoustic emissions (DPOAEs), were elevated by approximately 10 dB in GABA(B1)-deficient mice, consistent with outer hair cell dysfunction. Olivocochlear efferent function, assessed via DPOAE suppression during efferent electrical stimulation, was unaffected by GABA(B1) deletion. GABA(B1)-deficient mice showed increased resistance to permanent acoustic injury, with mean threshold shifts approximately 25 dB smaller than wild-types after exposure to 8-16-kHz noise at 100 dB for 2 h. In contrast, there was no vulnerability difference to temporary acoustic injury following exposure to the same noise at 94 dB for 15 min. Our results suggest that GABAergic signaling in type II afferent neurons may be required for normal outer hair cell amplifier function at low sound levels and may also modulate outer hair cell responses to high-level sound.
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Affiliation(s)
- Stéphane F Maison
- Department of Otology and Laryngology, Harvard Medical School and Eaton-Peabody Laboratory, Massachusetts Eye & Ear Infirmary, 243 Charles St., Boston, MA 02114-3096, USA.
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Nagai Y, Sano H, Yokoi M. Transgenic expression of Cre recombinase in mitral/tufted cells of the olfactory bulb. Genesis 2008; 43:12-6. [PMID: 16106355 DOI: 10.1002/gene.20146] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Olfactory information is conveyed from the periphery to the olfactory cortices through mitral and tufted (M/T) cells in the olfactory bulb. A mouse with a specific expression of Cre recombinase in M/T cells is essential for genetic marking of M/T cells and manipulating their properties. Protocadherin 21 (Pcdh21) expression is highly restricted to M/T cells. Here we report a transgenic mouse line, Pcdh21-Cre, in which 10-kb mouse Pcdh21 promoter drives the expression of Cre recombinase. In Pcdh21-Cre mice, Cre recombinase activity is predominantly detected in M/T cells, visualized with the anti-CFP immunostaining in offspring of a cross between Pcdh21-Cre and the reporter Rosa26-loxP-stop-loxP-CFP strain. These results demonstrate that the 10-kb Pcdh21 promoter can drive transcription in M/T cells and Pcdh21-Cre mice can be used to excise floxed DNA fragments in M/T cells, which provides a valuable tool to reveal the structure and function of the central olfactory circuits.
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Affiliation(s)
- Yumiko Nagai
- Molecular Neurogenetics Unit, HMRO, Kyoto University Graduate School of Medicine, Yoshida-Konoe, Sakyo, Kyoto, Japan
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40
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Magnaghi V, Ballabio M, Camozzi F, Colleoni M, Consoli A, Gassmann M, Lauria G, Motta M, Procacci P, Trovato AE, Bettler B. Altered peripheral myelination in mice lacking GABAB receptors. Mol Cell Neurosci 2008; 37:599-609. [DOI: 10.1016/j.mcn.2007.12.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Revised: 11/20/2007] [Accepted: 12/06/2007] [Indexed: 01/11/2023] Open
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Bonaventura MM, Catalano PN, Chamson-Reig A, Arany E, Hill D, Bettler B, Saravia F, Libertun C, Lux-Lantos VA. GABAB receptors and glucose homeostasis: evaluation in GABAB receptor knockout mice. Am J Physiol Endocrinol Metab 2008; 294:E157-67. [PMID: 17971510 DOI: 10.1152/ajpendo.00615.2006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
GABA has been proposed to inhibit insulin secretion through GABAB receptors (GABABRs) in pancreatic beta-cells. We investigated whether GABABRs participated in the regulation of glucose homeostasis in vivo. The animals used in this study were adult male and female BALB/C mice, mice deficient in the GABAB1 subunit of the GABABR (GABAB(-/-)), and wild types (WT). Blood glucose was measured under fasting/fed conditions and in glucose tolerance tests (GTTs) with a Lifescan Glucose meter, and serum insulin was measured by ELISA. Pancreatic insulin content and islet insulin were released by RIA. Western blots for the GABAB1 subunit in islet membranes and immunohistochemistry for insulin and GABAB1 were performed in both genotypes. BALB/C mice preinjected with Baclofen (GABABR agonist, 7.5 mg/kg ip) presented impaired GTTs and decreased insulin secretion compared with saline-preinjected controls. GABAB(-/-) mice showed fasting and fed glucose levels similar to WT. GABAB(-/-) mice showed improved GTTs at moderate glucose overloads (2 g/kg). Baclofen pretreatment did not modify GTTs in GABAB(-/-) mice, whereas it impaired normal glycemia reinstatement in WT. Baclofen inhibited glucose-stimulated insulin secretion in WT isolated islets but was without effect in GABAB(-/-) islets. In GABAB(-/-) males, pancreatic insulin content was increased, basal and glucose-stimulated insulin secretion were augmented, and impaired insulin tolerance test and increased homeostatic model assessment of insulin resistance index were determined. Immunohistochemistry for insulin demonstrated an increase of very large islets in GABAB(-/-) males. Results demonstrate that GABABRs are involved in the regulation of glucose homeostasis in vivo and that the constitutive absence of GABABRs induces alterations in pancreatic histology, physiology, and insulin resistance.
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Affiliation(s)
- M M Bonaventura
- Instituto de Biología y Medicina Experimental-Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, Buenos Aires, Argentina
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42
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Cheng Z, Tu C, Rodriguez L, Chen TH, Dvorak MM, Margeta M, Gassmann M, Bettler B, Shoback D, Chang W. Type B gamma-aminobutyric acid receptors modulate the function of the extracellular Ca2+-sensing receptor and cell differentiation in murine growth plate chondrocytes. Endocrinology 2007; 148:4984-92. [PMID: 17615148 DOI: 10.1210/en.2007-0653] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Extracellular calcium-sensing receptors (CaRs) and metabotropic or type B gamma-aminobutyric acid receptors (GABA-B-Rs), two closely related members of family C of the G protein-coupled receptor superfamily, dimerize in the formation of signaling and membrane-anchored receptor complexes. We tested whether CaRs and two GABA-B-R subunits (R1 and R2) are expressed in mouse growth plate chondrocytes (GPCs) by PCR and immunocytochemistry and whether interactions between these receptors influence the expression and function of the CaR and extracellular Ca(2+)-mediated cell differentiation. Both CaRs and the GABA-B-R1 and -R2 were expressed in the same zones of the growth plate and extensively colocalized in intracellular compartments and on the membranes of cultured GPCs. The GABA-B-R1 co-immunoprecipitated with the CaR, confirming a physical interaction between the two receptors in GPCs. In vitro knockout of GABA-B-R1 genes, using a Cre-lox recombination strategy, blunted the ability of high extracellular Ca(2+) concentration to activate phospholipase C and ERK1/2, suppressed cell proliferation, and enhanced apoptosis in cultured GPCs. In GPCs, in which the GABA-B-R1 was acutely knocked down, there was reduced expression of early chondrocyte markers, aggrecan and type II collagen, and increased expression of the late differentiation markers, type X collagen and osteopontin. These results support the idea that physical interactions between CaRs and GABA-B-R1s modulate the growth and differentiation of GPCs, potentially by altering the function of CaRs.
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Affiliation(s)
- Zhiqiang Cheng
- Endocrine Research Unit, Department of Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA 94121, USA
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43
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Chang W, Tu C, Cheng Z, Rodriguez L, Chen TH, Gassmann M, Bettler B, Margeta M, Jan LY, Shoback D. Complex Formation with the Type B γ-Aminobutyric Acid Receptor Affects the Expression and Signal Transduction of the Extracellular Calcium-sensing Receptor. J Biol Chem 2007; 282:25030-40. [PMID: 17591780 DOI: 10.1074/jbc.m700924200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We co-immunoprecipitated the Ca(2+)-sensing receptor (CaR) and type B gamma-aminobutyric acid receptor (GABA-B-R) from human embryonic kidney (HEK)-293 cells expressing these receptors and from brain lysates where both receptors are present. CaRs extensively co-localized with the two subunits of the GABA-B-R (R1 and R2) in HEK-293 cell membranes and intracellular organelles. Coexpressing CaRs and GABA-B-R1s in HEK-293 cells suppressed the total cellular and cell surface expression of CaRs and inhibited phospholipase C activation in response to high extracellular [Ca(2+)] ([Ca(2+)](e)). In contrast, coexpressing CaRs and GABA-B-R2s enhanced CaR expression and signaling responses to raising [Ca(2+)](e). The latter effects of the GABA-B-R2 on the CaR were blunted by coexpressing the GABA-B-R1. Coexpressing the CaR with GABA-B-R1 or R2 enhanced the total cellular and cell surface expression of the GABA-B-R1 or R2, respectively. Studies with truncated CaRs indicated that the N-terminal extracellular domain of the CaR participated in the interaction of the CaR with the GABA-B-R1 and R2. In cultured mouse hippocampal neurons, CaRs co-localized with the GABA-B-R1 and R2. CaRs and GABA-B-R1s also co-immunoprecipitated from brain lysates. The expression of the CaR was increased in lysates from GABA-B-R1 knock-out mouse brains and in cultured hippocampal neurons with their GABA-B-R1 genes deleted in vitro. Thus, CaRs and GABA-B-R subunits can form heteromeric complexes in cells, and their interactions affect cell surface expression and signaling of CaR, which may contribute to extracellular Ca(2+)-dependent receptor activation in target tissues.
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Affiliation(s)
- Wenhan Chang
- Endocrine Research Unit, Department of Veterans Affairs Medical Center, Department of Medicine, University of California, San Francisco, California 94121, USA.
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44
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Maison SF, Vetter DE, Liberman MC. A novel effect of cochlear efferents: in vivo response enhancement does not require alpha9 cholinergic receptors. J Neurophysiol 2007; 97:3269-78. [PMID: 17344378 DOI: 10.1152/jn.00067.2007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Outer hair cells in the mammalian cochlea receive a cholinergic efferent innervation that constitutes the effector arm of a sound-evoked negative feedback loop. The well-studied suppressive effects of acetylcholine (ACh) release from efferent terminals are mediated by alpha9/alpha10 ACh receptors and are potently blocked by strychnine. Here, we report a novel, efferent-mediated enhancement of cochlear sound-evoked neural responses and otoacoustic emissions in mice. In controls, a slow enhancement of response amplitude to supranormal levels appears after recovery from the classic suppressive effects seen during a 70-s epoch of efferent shocks. The magnitude of post-shock enhancement can be as great as 10 dB and tends to be greater for high-frequency acoustic stimuli. Systemic strychnine at 10 mg/kg eliminates efferent-induced suppression, revealing a purely enhancing effect of efferent shocks, which peaks within 5 s after efferent-stimulation onset, maintains a constant level through the stimulation epoch, and slowly decays back to baseline with a time constant of approximately 100 s. In mice with targeted deletion of the alpha9 ACh receptor subunit, efferent-evoked effects resemble those in wild types with strychnine blockade, further showing that this novel efferent effect is fundamentally different from all cholinergic effects previously reported.
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MESH Headings
- Acetylcholine/metabolism
- Acoustic Stimulation/methods
- Animals
- Cochlea/cytology
- Cochlea/drug effects
- Cochlea/physiology
- Dose-Response Relationship, Radiation
- Efferent Pathways/drug effects
- Efferent Pathways/physiology
- Evoked Potentials, Auditory/drug effects
- Evoked Potentials, Auditory/physiology
- Evoked Potentials, Auditory/radiation effects
- Glycine Agents/pharmacology
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Models, Biological
- Otoacoustic Emissions, Spontaneous/drug effects
- Otoacoustic Emissions, Spontaneous/physiology
- Reaction Time/drug effects
- Reaction Time/physiology
- Reaction Time/radiation effects
- Receptors, Nicotinic/genetics
- Receptors, Nicotinic/physiology
- Strychnine/pharmacology
- Time Factors
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Affiliation(s)
- Stéphane F Maison
- Department of Otology and Laryngology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, MA 02114-3096, USA.
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45
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Abstract
In the basal ganglia the effects of gamma-aminobutyrate (GABA) are mediated by both ionotropic (GABA(A)) and metabotropic (GABA(B)) receptors. Although the existence and widespread distribution in the CNS of the GABA(B) receptor had been established in the 1980s the field of GABA(B) research was revolutionized with the discovery that two related G-protein-coupled receptors (GPCRs) needed to dimerize to form the functional GABA(B) receptor at the cell surface. This finding lead to a number of studies of oligomerization in GPCRs and detailed pharmacological studies of the cloned receptors and their splice variants. Particular interest has focused on the proteins interacting with the receptor which may be important in mediating the longer term signalling effects of the receptor and modifying its cellular localization or physiology. The cloning of the GABA(B) receptors also lead to the identification of the first compounds interacting in an allosteric fashion with the receptor some of which may have therapeutic value. Most recently "knockouts" of both the GABA(B) subunits have been produced where in general as expected there is a loss of the majority of the inhibitory effects of the GABA(B) receptor.
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Affiliation(s)
- Piers C Emson
- The Babraham Institute, Babraham Research Campus, Cambridge CB2 4AT, UK.
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46
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Abstract
The G-protein-coupled receptor signaling system, consisting of a huge variety of receptors as well as of many G-proteins and effectors, operates in every cell and is involved in many physiological and pathological processes. The versatility of this system and the involvement of specific components makes G-protein-coupled receptors and their signaling pathways ideal targets for pharmacological interventions. Classical mouse knockout models have often provided important preliminary insights into the biological roles of individual receptors and signaling pathways and they are routinely used in the process of target validation. The recent development of efficient conditional mutagenesis techniques now allows a much more detailed analysis of G-protein-mediated signaling transduction processes. This review summarizes some of the areas in which progress has recently been made by applying conditional mutagenesis of genes coding for G-proteins and G-protein-coupled receptors.
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Affiliation(s)
- S Offermanns
- Institute of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany.
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47
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Kornau HC. GABAB receptors and synaptic modulation. Cell Tissue Res 2006; 326:517-33. [PMID: 16932937 DOI: 10.1007/s00441-006-0264-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2006] [Accepted: 05/31/2006] [Indexed: 12/18/2022]
Abstract
GABA(B) receptors modulate transmitter release and postsynaptic membrane potential at various types of central synapses. They function as heterodimers of two related seven-transmembrane domain receptor subunits. Trafficking, activation and signalling of GABA(B) receptors are regulated both by allosteric interactions between the subunits and by the binding of additional proteins. Recent studies have shed light on the roles of GABA(B) receptors in plasticity processes at excitatory synapses. This review summarizes our knowledge of the localization, structure and function of GABA(B) receptors in the central nervous system and their use as drug targets for neurological and psychiatric disorders.
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Affiliation(s)
- Hans-Christian Kornau
- Center for Molecular Neurobiology (ZMNH), University of Hamburg, Falkenried 94, 20251 Hamburg, Germany.
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