1
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Handforth A, Singh RP, Kosoyan HP, Kadam PA. A Role for GABA A Receptor β3 Subunits in Mediating Harmaline Tremor Suppression by Alcohol: Implications for Essential Tremor Therapy. Tremor Other Hyperkinet Mov (N Y) 2024; 14:20. [PMID: 38681506 PMCID: PMC11049614 DOI: 10.5334/tohm.834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 03/31/2024] [Indexed: 05/01/2024] Open
Abstract
Background Essential tremor patients may find that low alcohol amounts suppress tremor. A candidate mechanism is modulation of α6β3δ extra-synaptic GABAA receptors, that in vitro respond to non-intoxicating alcohol levels. We previously found that low-dose alcohol reduces harmaline tremor in wild-type mice, but not in littermates lacking δ or α6 subunits. Here we addressed whether low-dose alcohol requires the β3 subunit for tremor suppression. Methods We tested whether low-dose alcohol suppresses tremor in cre-negative mice with intact β3 exon 3 flanked by loxP, and in littermates in which this region was excised by cre expressed under the α6 subunit promotor. Tremor in the harmaline model was measured as a percentage of motion power in the tremor bandwidth divided by overall motion power. Results Alcohol, 0.500 and 0.575 g/kg, reduced harmaline tremor compared to vehicle-treated controls in floxed β3 cre- mice, but had no effect on tremor in floxed β3 cre+ littermates that have β3 knocked out. This was not due to potential interference of α6 expression by the insertion of the cre gene into the α6 gene since non-floxed β3 cre+ and cre- littermates exhibited similar tremor suppression by alcohol. Discussion As α6β3δ GABAA receptors are sensitive to low-dose alcohol, and cerebellar granule cells express β3 and are the predominant brain site for α6 and δ expression together, our overall findings suggest alcohol acts to suppress tremor by modulating α6β3δ GABAA receptors on these cells. Novel drugs that target this receptor may potentially be effective and well-tolerated for essential tremor. Highlights We previously found with the harmaline essential tremor model that GABAA receptors containing α6 and δ subunits mediate tremor suppression by alcohol. We now show that β3 subunits in α6-expressing cells, likely cerebellar granule cells, are also required, indicating that alcohol suppresses tremor by modulating α6β3δ extra-synaptic GABAA receptors.
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Affiliation(s)
- Adrian Handforth
- Neurology Service, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - Ram P. Singh
- Research Service, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - Hovsep P. Kosoyan
- Research Service, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - Pournima A. Kadam
- Research Service, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, USA
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2
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Tasnim A, Alkislar I, Hakim R, Turecek J, Abdelaziz A, Orefice LL, Ginty DD. The developmental timing of spinal touch processing alterations predicts behavioral changes in genetic mouse models of autism spectrum disorders. Nat Neurosci 2024; 27:484-496. [PMID: 38233682 PMCID: PMC10917678 DOI: 10.1038/s41593-023-01552-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 12/12/2023] [Indexed: 01/19/2024]
Abstract
Altered somatosensory reactivity is frequently observed among individuals with autism spectrum disorders (ASDs). Here, we report that although multiple mouse models of ASD exhibit aberrant somatosensory behaviors in adulthood, some models exhibit altered tactile reactivity as early as embryonic development, whereas in others, altered reactivity emerges later in life. Additionally, tactile overreactivity during neonatal development is associated with anxiety-like behaviors and social behavior deficits in adulthood, whereas tactile overreactivity that emerges later in life is not. The locus of circuit disruption dictates the timing of aberrant tactile behaviors, as altered feedback or presynaptic inhibition of peripheral mechanosensory neurons leads to abnormal tactile reactivity during neonatal development, whereas disruptions in feedforward inhibition in the spinal cord lead to touch reactivity alterations that manifest later in life. Thus, the developmental timing of aberrant touch processing can predict the manifestation of ASD-associated behaviors in mouse models, and differential timing of sensory disturbance onset may contribute to phenotypic diversity across individuals with ASD.
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Affiliation(s)
- Aniqa Tasnim
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Ilayda Alkislar
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Richard Hakim
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Josef Turecek
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Amira Abdelaziz
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Lauren L Orefice
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - David D Ginty
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA.
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3
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Kaplan HS, Logeman BL, Zhang K, Santiago C, Sohail N, Naumenko S, Ho Sui SJ, Ginty DD, Ren B, Dulac C. Sensory Input, Sex, and Function Shape Hypothalamic Cell Type Development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.23.576835. [PMID: 38328205 PMCID: PMC10849564 DOI: 10.1101/2024.01.23.576835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Mammalian behavior and physiology undergo dramatic changes in early life. Young animals rely on conspecifics to meet their homeostatic needs, until weaning and puberty initiate nutritional independence and sex-specific social interactions, respectively. How neuronal populations regulating homeostatic functions and social behaviors develop and mature during these transitions remains unclear. We used paired transcriptomic and chromatin accessibility profiling to examine the developmental trajectories of neuronal populations in the hypothalamic preoptic region, where cell types with key roles in physiological and behavioral control have been identified1-6. These data reveal a remarkable diversity of developmental trajectories shaped by the sex of the animal, and the location and behavioral or physiological function of the corresponding cell types. We identify key stages of preoptic development, including the perinatal emergence of sex differences, postnatal maturation and subsequent refinement of signaling networks, and nonlinear transcriptional changes accelerating at the time of weaning and puberty. We assessed preoptic development in various sensory mutants and find a major role for vomeronasal sensing in the timing of preoptic cell type maturation. These results provide novel insights into the development of neurons controlling homeostatic functions and social behaviors and lay ground for examining the dynamics of these functions in early life.
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Affiliation(s)
- Harris S. Kaplan
- Department of Molecular and Cellular Biology, Howard Hughes Medical Institute, Center for Brain Science, Harvard University, Cambridge, MA, USA
| | - Brandon L. Logeman
- Department of Molecular and Cellular Biology, Howard Hughes Medical Institute, Center for Brain Science, Harvard University, Cambridge, MA, USA
| | - Kai Zhang
- Department of Cellular and Molecular Medicine, Center for Epigenomics, University of California, San Diego School of Medicine, La Jolla, CA 92093, USA
- Current address: Westlake Laboratory of Life Sciences and Biomedicine, School of Life Sciences, Westlake University, Hangzhou, China
| | - Celine Santiago
- Department of Neurobiology, Harvard Medical School, Howard Hughes Medical Institute, 220 Longwood Ave, Boston, MA, 02115, USA
| | - Noor Sohail
- Department of Biostatistics, Harvard Chan School of Public Health, Boston, MA, USA
| | - Serhiy Naumenko
- Department of Biostatistics, Harvard Chan School of Public Health, Boston, MA, USA
- Newborn Screening Ontario, Ottawa, ON, Canada
| | - Shannan J. Ho Sui
- Department of Biostatistics, Harvard Chan School of Public Health, Boston, MA, USA
| | - David D. Ginty
- Department of Neurobiology, Harvard Medical School, Howard Hughes Medical Institute, 220 Longwood Ave, Boston, MA, 02115, USA
| | - Bing Ren
- Department of Cellular and Molecular Medicine, Center for Epigenomics, University of California, San Diego School of Medicine, La Jolla, CA 92093, USA
| | - Catherine Dulac
- Department of Molecular and Cellular Biology, Howard Hughes Medical Institute, Center for Brain Science, Harvard University, Cambridge, MA, USA
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4
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Arias HR, De Deurwaerdère P, Scholze P, Sakamoto S, Hamachi I, Di Giovanni G, Chagraoui A. Coronaridine congeners induce sedative and anxiolytic-like activity in naïve and stressed/anxious mice by allosteric mechanisms involving increased GABA A receptor affinity for GABA. Eur J Pharmacol 2023:175854. [PMID: 37331683 DOI: 10.1016/j.ejphar.2023.175854] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/04/2023] [Accepted: 06/12/2023] [Indexed: 06/20/2023]
Abstract
The sedative and anxiolytic-like activity of two coronaridine congeners, (+)-catharanthine and (-)-18-methoxycoronaridine (18-MC), was studied in male and female mice. The underlying molecular mechanism was subsequently determined by fluorescence imaging and radioligand binding experiments. The loss of righting reflex and locomotor activity results showed that both (+)-catharanthine and (-)-18-MC induce sedative effects at doses of 63 and 72 mg/kg in a sex-independent manner. At a lower dose (40 mg/kg), only (-)-18-MC induced anxiolytic-like activity in naïve mice (elevated O-maze test), whereas both congeners were effective in mice under stressful/anxiogenic conditions (light/dark transition test) and in stressed/anxious mice (novelty-suppressed feeding test), where the latter effect lasted for 24 h. Coronaridine congeners did not block pentylenetetrazole-induced anxiogenic-like activity in mice. Considering that pentylenetetrazole inhibits GABAA receptors, this result supports a role for this receptor in the activity mediated by coronaridine congeners. Functional and radioligand binding results showed that coronaridine congeners interact with a site different from that for benzodiazepines, increasing GABAA receptor affinity for GABA. Our study showed that coronaridine congeners induce sedative and anxiolytic-like activity in naïve and stressed/anxious mice in a sex-independent fashion, likely by a benzodiazepine-independent allosteric mechanism that increases GABAA receptor affinity for GABA.
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Affiliation(s)
- Hugo R Arias
- Department of Pharmacology and Physiology, Oklahoma State University College of Osteopathic Medicine, Tahlequah, OK, USA
| | - Philippe De Deurwaerdère
- Centre National de la Recherche Scientifique, Institut des Neurosciences Intégratives et Cognitives d'Aquitaine, UMR, 5287, Bordeaux, France
| | - Petra Scholze
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Seiji Sakamoto
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Itaru Hamachi
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Giuseppe Di Giovanni
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Abdeslam Chagraoui
- Department of Medical Biochemistry, Rouen University Hospital, CHU de Rouen, France; Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Normandie University, UNIROUEN, INSERM U1239, Institute for Research and Innovation in Biomedicine of Normandy (IRIB) Rouen, France.
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5
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Tasnim A, Alkislar I, Hakim R, Turecek J, Abdelaziz A, Orefice LL, Ginty DD. The developmental timing of spinal touch processing alterations and its relation to ASD-associated behaviors in mouse models. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.09.539589. [PMID: 37214862 PMCID: PMC10197556 DOI: 10.1101/2023.05.09.539589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Altered somatosensory reactivity is frequently observed among individuals with autism spectrum disorders (ASDs). Here, we report that while multiple mouse models of ASD exhibit aberrant somatosensory behaviors in adulthood, some models exhibit altered tactile reactivity as early as embryonic development, while in others, altered reactivity emerges later in life. Additionally, tactile over-reactivity during neonatal development is associated with anxiety-like behaviors and social interaction deficits in adulthood, whereas tactile over-reactivity that emerges later in life is not. The locus of circuit disruption dictates the timing of aberrant tactile behaviors: altered feedback or presynaptic inhibition of peripheral mechanosensory neurons leads to abnormal tactile reactivity during neonatal development, while disruptions in feedforward inhibition in the spinal cord lead to touch reactivity alterations that manifest later in life. Thus, the developmental timing of aberrant touch processing can predict the manifestation of ASD-associated behaviors in mouse models, and differential timing of sensory disturbance onset may contribute to phenotypic diversity across individuals with ASD.
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6
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Kourdougli N, Portera-Cailliau C. aGABRacadabra: A surprising new role for GABA A receptors in cortical development. Neuron 2023; 111:146-149. [PMID: 36657397 DOI: 10.1016/j.neuron.2022.12.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In this issue of Neuron, Babij, Ferrer, and colleagues provide new evidence that β3 subunit of GABAA receptors is critical for the maturation of functional networks in the neonatal somatosensory cortex.
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Affiliation(s)
- Nazim Kourdougli
- Department of Neurology, David Geffen School of Medicine at UCLA, 710 Westwood Plaza, Los Angeles, CA 90095, USA
| | - Carlos Portera-Cailliau
- Department of Neurology, David Geffen School of Medicine at UCLA, 710 Westwood Plaza, Los Angeles, CA 90095, USA; Department of Neurobiology, David Geffen School of Medicine at UCLA, 710 Westwood Plaza, Los Angeles, CA 90095, USA.
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7
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Babij R, Ferrer C, Donatelle A, Wacks S, Buch AM, Niemeyer JE, Ma H, Duan ZRS, Fetcho RN, Che A, Otsuka T, Schwartz TH, Huang BS, Liston C, De Marco García NV. Gabrb3 is required for the functional integration of pyramidal neuron subtypes in the somatosensory cortex. Neuron 2023; 111:256-274.e10. [PMID: 36446382 PMCID: PMC9852093 DOI: 10.1016/j.neuron.2022.10.037] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 08/30/2022] [Accepted: 10/27/2022] [Indexed: 11/29/2022]
Abstract
Dysfunction of gamma-aminobutyric acid (GABA)ergic circuits is strongly associated with neurodevelopmental disorders. However, it is unclear how genetic predispositions impact circuit assembly. Using in vivo two-photon and widefield calcium imaging in developing mice, we show that Gabrb3, a gene strongly associated with autism spectrum disorder (ASD) and Angelman syndrome (AS), is enriched in contralaterally projecting pyramidal neurons and is required for inhibitory function. We report that Gabrb3 ablation leads to a developmental decrease in GABAergic synapses, increased local network synchrony, and long-lasting enhancement in functional connectivity of contralateral-but not ipsilateral-pyramidal neuron subtypes. In addition, Gabrb3 deletion leads to increased cortical response to tactile stimulation at neonatal stages. Using human transcriptomics and neuroimaging datasets from ASD subjects, we show that the spatial distribution of GABRB3 expression correlates with atypical connectivity in these subjects. Our studies reveal a requirement for Gabrb3 during the emergence of interhemispheric circuits for sensory processing.
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Affiliation(s)
- Rachel Babij
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA.,Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD Program, New York, NY 10021, USA
| | - Camilo Ferrer
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Alexander Donatelle
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Sam Wacks
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Amanda M Buch
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - James E Niemeyer
- Department of Neurological Surgery, Weill Cornell Medicine, New-York Presbyterian Hospital, New York, NY 10021, USA
| | - Hongtao Ma
- Department of Neurological Surgery, Weill Cornell Medicine, New-York Presbyterian Hospital, New York, NY 10021, USA
| | - Zhe Ran S Duan
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA.,Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD Program, New York, NY 10021, USA
| | - Robert N Fetcho
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA.,Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD Program, New York, NY 10021, USA
| | - Alicia Che
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA.,Current affiliation: Department of Psychiatry, Yale School of Medicine, New Haven, CT 06519, USA
| | - Takumi Otsuka
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Theodore H Schwartz
- Department of Neurological Surgery, Weill Cornell Medicine, New-York Presbyterian Hospital, New York, NY 10021, USA
| | - Ben S Huang
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Conor Liston
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Natalia V De Marco García
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA.,Lead Contact,Correspondence to
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8
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Chirila AM, Rankin G, Tseng SY, Emanuel AJ, Chavez-Martinez CL, Zhang D, Harvey CD, Ginty DD. Mechanoreceptor signal convergence and transformation in the dorsal horn flexibly shape a diversity of outputs to the brain. Cell 2022; 185:4541-4559.e23. [PMID: 36334588 PMCID: PMC9691598 DOI: 10.1016/j.cell.2022.10.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 08/22/2022] [Accepted: 10/11/2022] [Indexed: 11/06/2022]
Abstract
The encoding of touch in the spinal cord dorsal horn (DH) and its influence on tactile representations in the brain are poorly understood. Using a range of mechanical stimuli applied to the skin, large-scale in vivo electrophysiological recordings, and genetic manipulations, here we show that neurons in the mouse spinal cord DH receive convergent inputs from both low- and high-threshold mechanoreceptor subtypes and exhibit one of six functionally distinct mechanical response profiles. Genetic disruption of DH feedforward or feedback inhibitory motifs, comprised of interneurons with distinct mechanical response profiles, revealed an extensively interconnected DH network that enables dynamic, flexible tuning of postsynaptic dorsal column (PSDC) output neurons and dictates how neurons in the primary somatosensory cortex respond to touch. Thus, mechanoreceptor subtype convergence and non-linear transformations at the earliest stage of the somatosensory hierarchy shape how touch of the skin is represented in the brain.
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Affiliation(s)
- Anda M Chirila
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Genelle Rankin
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Shih-Yi Tseng
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Alan J Emanuel
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Carmine L Chavez-Martinez
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Dawei Zhang
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Christopher D Harvey
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - David D Ginty
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA.
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9
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Vien TN, Ackley MA, Doherty JJ, Moss SJ, Davies PA. Preventing Phosphorylation of the GABAAR β3 Subunit Compromises the Behavioral Effects of Neuroactive Steroids. Front Mol Neurosci 2022; 15:817996. [PMID: 35431797 PMCID: PMC9009507 DOI: 10.3389/fnmol.2022.817996] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 03/09/2022] [Indexed: 11/26/2022] Open
Abstract
Neuroactive steroids (NASs) have potent anxiolytic, anticonvulsant, sedative, and hypnotic actions, that reflect in part their efficacy as GABAAR positive allosteric modulators (PAM). In addition to this, NAS exert metabotropic effects on GABAergic inhibition via the activation of membrane progesterone receptors (mPRs), which are G-protein coupled receptors. mPR activation enhances the phosphorylation of residues serine 408 and 409 (S408/9) in the β3 subunit of GABAARs, increasing their accumulation in the plasma membrane leading to a sustained increase in tonic inhibition. To explore the significance of NAS-induced phosphorylation of GABAARs, we used mice in which S408/9 in the β3 subunit have been mutated to alanines, mutations that prevent the metabotropic actions of NASs on GABAAR function while preserving NAS allosteric potentiation of GABAergic current. While the sedative actions of NAS were comparable to WT, their anxiolytic actions were reduced in S408/9A mice. Although the induction of hypnosis by NAS were maintained in the mutant mice the duration of the loss of righting reflex was significantly shortened. Finally, ability of NAS to terminate diazepam pharmacoresistant seizures was abolished in S408/9A mice. In conclusion, our results suggest that S408/9 in the GABAAR β3 subunit contribute to the anxiolytic and anticonvulsant efficacy of NAS, in addition to their ability to regulate the loss of righting reflex.
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Affiliation(s)
- Thuy N. Vien
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, United States
| | - Michael A. Ackley
- Research and Non-clinical Development, Sage Therapeutics, Inc., Cambridge, MA, United States
| | - James J. Doherty
- Research and Non-clinical Development, Sage Therapeutics, Inc., Cambridge, MA, United States
| | - Stephen J. Moss
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, United States
- *Correspondence: Stephen J. Moss,
| | - Paul A. Davies
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, United States
- Paul A. Davies,
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10
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Agrud A, Subburaju S, Goel P, Ren J, Kumar AS, Caldarone BJ, Dai W, Chavez J, Fukumura D, Jain RK, Kloner RA, Vasudevan A. Gabrb3 endothelial cell-specific knockout mice display abnormal blood flow, hypertension, and behavioral dysfunction. Sci Rep 2022; 12:4922. [PMID: 35318369 PMCID: PMC8941104 DOI: 10.1038/s41598-022-08806-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 03/04/2022] [Indexed: 11/17/2022] Open
Abstract
Our recent studies uncovered a novel GABA signaling pathway in embryonic forebrain endothelial cells that works independently from neuronal GABA signaling and revealed that disruptions in endothelial GABAA receptor-GABA signaling from early embryonic stages can directly contribute to the origin of psychiatric disorders. In the GABAA receptor β3 subunit endothelial cell conditional knockout (Gabrb3ECKO) mice, the β3 subunit is deleted selectively from endothelial cells, therefore endothelial GABAA receptors become inactivated and dysfunctional. There is a reduction in vessel densities and increased vessel morphology in the Gabrb3ECKO telencephalon that persists in the adult neocortex. Gabrb3ECKO mice show behavioral deficits such as impaired reciprocal social interactions, communication deficits, heightened anxiety, and depression. Here, we characterize the functional changes in Gabrb3ECKO mice by evaluating cortical blood flow, examine the consequences of loss of endothelial Gabrb3 on cardiac tissue, and define more in-depth altered behaviors. Red blood cell velocity and blood flow were increased in the cortical microcirculation of the Gabrb3ECKO mice. The Gabrb3ECKO mice had a reduction in vessel densities in the heart, similar to the brain; exhibited wavy, myocardial fibers, with elongated 'worm-like' nuclei in their cardiac histology, and developed hypertension. Additional alterations in behavioral function were observed in the Gabrb3ECKO mice such as increased spontaneous exploratory activity and rearing in an open field, reduced short term memory, decreased ambulatory activity in CLAMS testing, and altered prepulse inhibition to startle, an important biomarker of psychiatric diseases such as schizophrenia. Our results imply that vascular Gabrb3 is a key player in the brain as well as the heart, and its loss in both organs can lead to concurrent development of psychiatric and cardiac dysfunction.
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Affiliation(s)
- Anass Agrud
- grid.280933.30000 0004 0452 8371Angiogenesis and Brain Development Laboratory, Huntington Medical Research Institutes (HMRI), 686 S Fair Oaks Avenue, Pasadena, CA 91105 USA
| | - Sivan Subburaju
- grid.280933.30000 0004 0452 8371Angiogenesis and Brain Development Laboratory, Huntington Medical Research Institutes (HMRI), 686 S Fair Oaks Avenue, Pasadena, CA 91105 USA ,grid.38142.3c000000041936754XDepartment of Psychiatry, Harvard Medical School, Boston, MA 02215 USA ,grid.240206.20000 0000 8795 072XDivision of Basic Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA 02478 USA
| | - Pranay Goel
- grid.280933.30000 0004 0452 8371Angiogenesis and Brain Development Laboratory, Huntington Medical Research Institutes (HMRI), 686 S Fair Oaks Avenue, Pasadena, CA 91105 USA
| | - Jun Ren
- grid.32224.350000 0004 0386 9924Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114 USA
| | - Ashwin Srinivasan Kumar
- grid.32224.350000 0004 0386 9924Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114 USA ,grid.116068.80000 0001 2341 2786Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Barbara J. Caldarone
- grid.38142.3c000000041936754XMouse Behavior Core, Department of Genetics, Harvard Medical School, Boston, MA USA
| | - Wangde Dai
- grid.280933.30000 0004 0452 8371Huntington Medical Research Institutes, Pasadena, CA USA ,grid.42505.360000 0001 2156 6853Division of Cardiovascular Medicine, Department of Medicine, Keck School of Medicine at University of Southern California, Los Angeles, CA USA
| | - Jesus Chavez
- grid.280933.30000 0004 0452 8371Huntington Medical Research Institutes, Pasadena, CA USA ,grid.42505.360000 0001 2156 6853Division of Cardiovascular Medicine, Department of Medicine, Keck School of Medicine at University of Southern California, Los Angeles, CA USA
| | - Dai Fukumura
- grid.32224.350000 0004 0386 9924Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114 USA
| | - Rakesh K. Jain
- grid.32224.350000 0004 0386 9924Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114 USA
| | - Robert A. Kloner
- grid.280933.30000 0004 0452 8371Huntington Medical Research Institutes, Pasadena, CA USA ,grid.42505.360000 0001 2156 6853Division of Cardiovascular Medicine, Department of Medicine, Keck School of Medicine at University of Southern California, Los Angeles, CA USA
| | - Anju Vasudevan
- Angiogenesis and Brain Development Laboratory, Huntington Medical Research Institutes (HMRI), 686 S Fair Oaks Avenue, Pasadena, CA, 91105, USA.
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11
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Manzella FM, Covey DF, Jevtovic-Todorovic V, Todorovic SM. Synthetic neuroactive steroids as new sedatives and anaesthetics: Back to the future. J Neuroendocrinol 2022; 34:e13086. [PMID: 35014105 PMCID: PMC8866223 DOI: 10.1111/jne.13086] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 12/03/2021] [Accepted: 12/22/2021] [Indexed: 02/03/2023]
Abstract
Since the 1990s, there has been waning interest in researching general anaesthetics (anaesthetics). Although currently used anaesthetics are mostly safe and effective, they are not without fault. In paediatric populations and neonatal animal models, they are associated with learning impairments and neurotoxicity. In an effort to research safer anaesthetics, we have gone back to re-examine neuroactive steroids as anaesthetics. Neuroactive steroids are steroids that have direct, local effects in the central nervous system. Since the discovery of their anaesthetic effects, neuroactive steroids have been consistently used in human or veterinary clinics as preferred anaesthetic agents. Although briefly abandoned for clinical use due to unwanted vehicle side effects, there has since been renewed interest in their therapeutic value. Neuroactive steroids are safe sedative/hypnotic and anaesthetic agents across various animal species. Importantly, unlike traditional anaesthetics, they do not cause extensive neurotoxicity in the developing rodent brain. Similar to traditional anaesthetics, neuroactive steroids are modulators of synaptic and extrasynaptic γ-aminobutyric acid type A (GABAA ) receptors and their interactions at the GABAA receptor are stereo- and enantioselective. Recent work has also shown that these agents act on other ion channels, such as high- and low-voltage-activated calcium channels. Through these mechanisms of action, neuroactive steroids modulate neuronal excitability, which results in characteristic burst suppression of the electroencephalogram, and a surgical plane of anaesthesia. However, in addition to their interactions with voltage and ligand gated ions channels, neuroactive steroids interact with membrane bound metabotropic receptors and xenobiotic receptors to facilitate signaling of prosurvival, antiapoptotic pathways. These pathways play a role in their neuroprotective effects in neuronal injury and may also prevent extensive apoptosis in the developing brain during anaesthesia. The current review explores the history of neuroactive steroids as anaesthetics in humans and animal models, their diverse mechanisms of action, and their neuroprotective properties.
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Affiliation(s)
- Francesca M Manzella
- Department of Anesthesiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Douglas F Covey
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, USA
- Taylor Family Institute for Innovative Psychiatric Research, Washington University in St. Louis School of Medicine, St. Louis, Missouri, USA
| | - Vesna Jevtovic-Todorovic
- Department of Anesthesiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Slobodan M Todorovic
- Department of Anesthesiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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12
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Belelli D, Hales TG, Lambert JJ, Luscher B, Olsen R, Peters JA, Rudolph U, Sieghart W. GABA A receptors in GtoPdb v.2021.3. IUPHAR/BPS GUIDE TO PHARMACOLOGY CITE 2021; 2021. [PMID: 35005623 DOI: 10.2218/gtopdb/f72/2021.3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The GABAA receptor is a ligand-gated ion channel of the Cys-loop family that includes the nicotinic acetylcholine, 5-HT3 and strychnine-sensitive glycine receptors. GABAA receptor-mediated inhibition within the CNS occurs by fast synaptic transmission, sustained tonic inhibition and temporally intermediate events that have been termed 'GABAA, slow' [45]. GABAA receptors exist as pentamers of 4TM subunits that form an intrinsic anion selective channel. Sequences of six α, three β, three γ, one δ, three ρ, one ε, one π and one θ GABAA receptor subunits have been reported in mammals [278, 235, 236, 283]. The π-subunit is restricted to reproductive tissue. Alternatively spliced versions of many subunits exist (e.g. α4- and α6- (both not functional) α5-, β2-, β3- and γ2), along with RNA editing of the α3 subunit [71]. The three ρ-subunits, (ρ1-3) function as either homo- or hetero-oligomeric assemblies [359, 50]. Receptors formed from ρ-subunits, because of their distinctive pharmacology that includes insensitivity to bicuculline, benzodiazepines and barbiturates, have sometimes been termed GABAC receptors [359], but they are classified as GABA A receptors by NC-IUPHAR on the basis of structural and functional criteria [16, 235, 236]. Many GABAA receptor subtypes contain α-, β- and γ-subunits with the likely stoichiometry 2α.2β.1γ [168, 235]. It is thought that the majority of GABAA receptors harbour a single type of α- and β - subunit variant. The α1β2γ2 hetero-oligomer constitutes the largest population of GABAA receptors in the CNS, followed by the α2β3γ2 and α3β3γ2 isoforms. Receptors that incorporate the α4- α5-or α 6-subunit, or the β1-, γ1-, γ3-, δ-, ε- and θ-subunits, are less numerous, but they may nonetheless serve important functions. For example, extrasynaptically located receptors that contain α6- and δ-subunits in cerebellar granule cells, or an α4- and δ-subunit in dentate gyrus granule cells and thalamic neurones, mediate a tonic current that is important for neuronal excitability in response to ambient concentrations of GABA [209, 272, 83, 19, 288]. GABA binding occurs at the β+/α- subunit interface and the homologous γ+/α- subunits interface creates the benzodiazepine site. A second site for benzodiazepine binding has recently been postulated to occur at the α+/β- interface ([254]; reviewed by [282]). The particular α-and γ-subunit isoforms exhibit marked effects on recognition and/or efficacy at the benzodiazepine site. Thus, receptors incorporating either α4- or α6-subunits are not recognised by 'classical' benzodiazepines, such as flunitrazepam (but see [356]). The trafficking, cell surface expression, internalisation and function of GABAA receptors and their subunits are discussed in detail in several recent reviews [52, 140, 188, 316] but one point worthy of note is that receptors incorporating the γ2 subunit (except when associated with α5) cluster at the postsynaptic membrane (but may distribute dynamically between synaptic and extrasynaptic locations), whereas as those incorporating the δ subunit appear to be exclusively extrasynaptic. NC-IUPHAR [16, 235, 3, 2] class the GABAA receptors according to their subunit structure, pharmacology and receptor function. Currently, eleven native GABAA receptors are classed as conclusively identified (i.e., α1β2γ2, α1βγ2, α3βγ2, α4βγ2, α4β2δ, α4β3δ, α5βγ2, α6βγ2, α6β2δ, α6β3δ and ρ) with further receptor isoforms occurring with high probability, or only tentatively [235, 236]. It is beyond the scope of this Guide to discuss the pharmacology of individual GABAA receptor isoforms in detail; such information can be gleaned in the reviews [16, 95, 168, 173, 143, 278, 216, 235, 236] and [9, 10]. Agents that discriminate between α-subunit isoforms are noted in the table and additional agents that demonstrate selectivity between receptor isoforms, for example via β-subunit selectivity, are indicated in the text below. The distinctive agonist and antagonist pharmacology of ρ receptors is summarised in the table and additional aspects are reviewed in [359, 50, 145, 223]. Several high-resolution cryo-electron microscopy structures have been described in which the full-length human α1β3γ2L GABAA receptor in lipid nanodiscs is bound to the channel-blocker picrotoxin, the competitive antagonist bicuculline, the agonist GABA (γ-aminobutyric acid), and the classical benzodiazepines alprazolam and diazepam [198].
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13
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Affiliation(s)
- Lauren L Orefice
- Department of Molecular Biology, Massachusetts General Hospital, and Department of Genetics, Harvard Medical School, Boston, MA 02114, USA.
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14
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Drug-selective Anesthetic Insensitivity of Zebrafish Lacking γ-Aminobutyric Acid Type A Receptor β3 Subunits. Anesthesiology 2020; 131:1276-1291. [PMID: 31567362 DOI: 10.1097/aln.0000000000002963] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Transgenic mouse studies suggest that γ-aminobutyric acid type A (GABAA) receptors containing β3 subunits mediate important effects of etomidate, propofol, and pentobarbital. Zebrafish, recently introduced for rapid discovery and characterization of sedative-hypnotics, could also accelerate pharmacogenetic studies if their transgenic phenotypes reflect those of mammals. The authors hypothesized that, relative to wild-type, GABAA-β3 functional knock-out (β3) zebrafish would show anesthetic sensitivity changes similar to those of β3 mice. METHODS Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 mutagenesis was used to create a β3 zebrafish line. Wild-type and β3 zebrafish were compared for fertility, growth, and craniofacial development. Sedative and hypnotic effects of etomidate, propofol, pentobarbital, alphaxalone, ketamine, tricaine, dexmedetomidine, butanol, and ethanol, along with overall activity and thigmotaxis were quantified in 7-day postfertilization larvae using video motion analysis of up to 96 animals simultaneously. RESULTS Xenopus oocyte electrophysiology showed that the wild-type zebrafish β3 gene encodes ion channels activated by propofol and etomidate, while the β3 zebrafish transgene does not. Compared to wild-type, β3 zebrafish showed similar morphology and growth, but more rapid swimming. Hypnotic EC50s (mean [95% CI]) were significantly higher for β3 versus wild-type larvae with etomidate (1.3 [1.0 to 1.6] vs. 0.6 [0.5 to 0.7] µM; P < 0.0001), propofol (1.1 [1.0 to 1.4] vs. 0.7 [0.6 to 0.8] µM; P = 0.0005), and pentobarbital (220 [190 to 240] vs. 130 [94 to 179] μM; P = 0.0009), but lower with ethanol (150 [106 to 213] vs. 380 [340 to 420] mM; P < 0.0001) and equivalent with other tested drugs. Comparing β3 versus wild-type sedative EC50s revealed a pattern similar to hypnosis. CONCLUSIONS Global β3 zebrafish are selectively insensitive to the same few sedative-hypnotics previously reported in β3 transgenic mice, indicating phylogenetic conservation of β3-containing GABAA receptors as anesthetic targets. Transgenic zebrafish are potentially valuable models for sedative-hypnotic mechanisms research.
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Xu P, Ni L, Tao Y, Ma Z, Hu T, Zhao X, Yu Z, Lu C, Zhao X, Ren J. Genome-wide association study for growth and fatness traits in Chinese Sujiang pigs. Anim Genet 2020; 51:314-318. [PMID: 31909836 DOI: 10.1111/age.12899] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/06/2019] [Indexed: 12/14/2022]
Abstract
Growth and fatness traits are complex and economically important traits in the pig industry. The molecular basis underlying porcine growth and fatness traits remains largely unknown. To uncover genetic loci and candidate genes for these traits, we explored the GeneSeek GGP Porcine 80K SNP chip to perform a GWAS for seven growth and fatness traits in 365 individuals from the Sujiang pig, a recently developed breed in China. We identified two, 17, one and 11 SNPs surpassing the suggestively significant threshold (P < 1.86 × 10-5 ) for body weight, chest circumference, chest width and backfat thickness respectively. Of these SNPs, 20 represent novel genetic loci, and five and four SNPs were respectively associated with chest circumference and backfat thickness at a genome-wide significant threshold (P < 9.31 × 10-7 ). Eight SNPs had a pleiotropic effect on both chest circumference and backfat thickness. The most remarkable locus resided in a region between 72.95 and 76.27 Mb on pig chromosome 4, harboring a number of previously reported quantitative trait loci related to backfat deposition. In addition to two reported genes (PLAG1 and TAS2R38), we identified four genes including GABRB3, ZNF106, XKR4 and MGAM as novel candidates for body weight and backfat thickness at the mapped loci. Our findings provide insights into the genetic architecture of porcine growth and fatness traits and potential markers for selective breeding of Chinese Sujiang pigs.
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Affiliation(s)
- P Xu
- School of Animal Science and Technology, Jiangsu Agri-animal Husbandry Vocational College, 225300, Taizhou, China
| | - L Ni
- School of Animal Science and Technology, Jiangsu Agri-animal Husbandry Vocational College, 225300, Taizhou, China.,Unit of Pig Breeding, Jiangsu Sujiang Pig Breeding Farm, 225400, Taixing, China
| | - Y Tao
- School of Animal Science and Technology, Jiangsu Agri-animal Husbandry Vocational College, 225300, Taizhou, China.,Unit of Pig Breeding, Jiangsu Sujiang Pig Breeding Farm, 225400, Taixing, China
| | - Z Ma
- School of Animal Science and Technology, Jiangsu Agri-animal Husbandry Vocational College, 225300, Taizhou, China
| | - T Hu
- School of Animal Science and Technology, Jiangsu Agri-animal Husbandry Vocational College, 225300, Taizhou, China
| | - X Zhao
- School of Animal Science and Technology, Jiangsu Agri-animal Husbandry Vocational College, 225300, Taizhou, China
| | - Z Yu
- School of Animal Science and Technology, Jiangsu Agri-animal Husbandry Vocational College, 225300, Taizhou, China
| | - C Lu
- School of Animal Science and Technology, Jiangsu Agri-animal Husbandry Vocational College, 225300, Taizhou, China
| | - X Zhao
- School of Animal Science and Technology, Jiangsu Agri-animal Husbandry Vocational College, 225300, Taizhou, China
| | - J Ren
- College of Animal Science, South China Agricultural University, 510642, Guangzhou, China
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16
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Orefice LL, Mosko JR, Morency DT, Wells MF, Tasnim A, Mozeika SM, Ye M, Chirila AM, Emanuel AJ, Rankin G, Fame RM, Lehtinen MK, Feng G, Ginty DD. Targeting Peripheral Somatosensory Neurons to Improve Tactile-Related Phenotypes in ASD Models. Cell 2019; 178:867-886.e24. [PMID: 31398341 PMCID: PMC6704376 DOI: 10.1016/j.cell.2019.07.024] [Citation(s) in RCA: 123] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 05/06/2019] [Accepted: 07/11/2019] [Indexed: 12/23/2022]
Abstract
Somatosensory over-reactivity is common among patients with autism spectrum disorders (ASDs) and is hypothesized to contribute to core ASD behaviors. However, effective treatments for sensory over-reactivity and ASDs are lacking. We found distinct somatosensory neuron pathophysiological mechanisms underlie tactile abnormalities in different ASD mouse models and contribute to some ASD-related behaviors. Developmental loss of ASD-associated genes Shank3 or Mecp2 in peripheral mechanosensory neurons leads to region-specific brain abnormalities, revealing links between developmental somatosensory over-reactivity and the genesis of aberrant behaviors. Moreover, acute treatment with a peripherally restricted GABAA receptor agonist that acts directly on mechanosensory neurons reduced tactile over-reactivity in six distinct ASD models. Chronic treatment of Mecp2 and Shank3 mutant mice improved body condition, some brain abnormalities, anxiety-like behaviors, and some social impairments but not memory impairments, motor deficits, or overgrooming. Our findings reveal a potential therapeutic strategy targeting peripheral mechanosensory neurons to treat tactile over-reactivity and select ASD-related behaviors.
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Affiliation(s)
- Lauren L Orefice
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Jacqueline R Mosko
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Danielle T Morency
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Michael F Wells
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 43 Vassar Street, Cambridge, MA 02139, USA
| | - Aniqa Tasnim
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Shawn M Mozeika
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Mengchen Ye
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Anda M Chirila
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Alan J Emanuel
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Genelle Rankin
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Ryann M Fame
- Department of Pathology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Maria K Lehtinen
- Department of Pathology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Guoping Feng
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 43 Vassar Street, Cambridge, MA 02139, USA
| | - David D Ginty
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA.
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17
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Furukawa T, Nikaido Y, Shimoyama S, Ogata Y, Kushikata T, Hirota K, Kanematsu T, Hirata M, Ueno S. Phospholipase C-related inactive protein type-1 deficiency affects anesthetic electroencephalogram activity induced by propofol and etomidate in mice. J Anesth 2019; 33:531-542. [PMID: 31332527 DOI: 10.1007/s00540-019-02663-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Accepted: 07/08/2019] [Indexed: 11/25/2022]
Abstract
PURPOSE The general anesthetics propofol and etomidate mainly exert their anesthetic actions via GABA A receptor (GABAA-R). The GABAA-R activity is influenced by phospholipase C-related inactive protein type-1 (PRIP-1), which is related to trafficking and subcellular localization of GABAA-R. PRIP-1 deficiency attenuates the behavioral reactions to propofol but not etomidate. However, the effect of these anesthetics and of PRIP-1 deficiency on brain activity of CNS are still unclear. In this study, we examined the effects of propofol and etomidate on the electroencephalogram (EEG). METHODS The cortical EEG activity was recorded in wild-type (WT) and PRIP-1 knockout (PRIP-1 KO) mice. All recorded EEG data were offline analyzed, and the power spectral density and 95% spectral edge frequency of EEG signals were compared between genotypes before and after injections of anesthetics. RESULTS PRIP-1 deficiency induced increases in EEG absolute powers, but did not markedly change the relative spectral powers during waking and sleep states in the absence of anesthesia. Propofol administration induced increases in low-frequency relative EEG activity and decreases in SEF95 values in WT but not in PRIP-1 KO mice. Following etomidate injection, low-frequency EEG power was increased in both genotype groups. At high frequency, the relative power in PRIP-1 KO mice was smaller than that in WT mice. CONCLUSIONS The lack of PRIP-1 disrupted the EEG power distribution, but did not affect the depth of anesthesia after etomidate administration. Our analyses suggest that PRIP-1 is differentially involved in anesthetic EEG activity with the regulation of GABAA-R activity.
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Affiliation(s)
- Tomonori Furukawa
- Department of Neurophysiology, Hirosaki University Graduate School of Medicine, 5 Zaihu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Yoshikazu Nikaido
- Department of Neurophysiology, Hirosaki University Graduate School of Medicine, 5 Zaihu-cho, Hirosaki, Aomori, 036-8562, Japan.,Department of Anesthesiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shuji Shimoyama
- Department of Neurophysiology, Hirosaki University Graduate School of Medicine, 5 Zaihu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Yoshiki Ogata
- Department of Neurophysiology, Hirosaki University Graduate School of Medicine, 5 Zaihu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Tetsuya Kushikata
- Department of Anesthesiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Kazuyoshi Hirota
- Department of Anesthesiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Takashi Kanematsu
- Department of Cellular and Molecular Pharmacology, Division of Basic Life Sciences, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Masato Hirata
- School of Dental Medicine, Fukuoka Dental College, Fukuoka, Japan
| | - Shinya Ueno
- Department of Neurophysiology, Hirosaki University Graduate School of Medicine, 5 Zaihu-cho, Hirosaki, Aomori, 036-8562, Japan. .,Research Center for Child Mental Development, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
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18
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Chiu CQ, Martenson JS, Yamazaki M, Natsume R, Sakimura K, Tomita S, Tavalin SJ, Higley MJ. Input-Specific NMDAR-Dependent Potentiation of Dendritic GABAergic Inhibition. Neuron 2019; 97:368-377.e3. [PMID: 29346754 DOI: 10.1016/j.neuron.2017.12.032] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 11/16/2017] [Accepted: 12/21/2017] [Indexed: 01/21/2023]
Abstract
Preservation of a balance between synaptic excitation and inhibition is critical for normal brain function. A number of homeostatic cellular mechanisms have been suggested to play a role in maintaining this balance, including long-term plasticity of GABAergic inhibitory synapses. Many previous studies have demonstrated a coupling of postsynaptic spiking with modification of perisomatic inhibition. Here, we demonstrate that activation of NMDA-type glutamate receptors leads to input-specific long-term potentiation of dendritic inhibition mediated by somatostatin-expressing interneurons. This form of plasticity is expressed postsynaptically and requires both CaMKIIα and the β2 subunit of the GABA-A receptor. Importantly, this process may function to preserve dendritic inhibition, as genetic deletion of NMDAR signaling results in a selective weakening of dendritic inhibition. Overall, our results reveal a new mechanism for linking excitatory and inhibitory input in neuronal dendrites and provide novel insight into the homeostatic regulation of synaptic transmission in cortical circuits.
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Affiliation(s)
- Chiayu Q Chiu
- Department of Neuroscience, Program in Cellular Neuroscience, Neurodegeneration, and Repair, Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA; Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso 2360102, Chile
| | - James S Martenson
- Department of Neuroscience, Program in Cellular Neuroscience, Neurodegeneration, and Repair, Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Maya Yamazaki
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Rie Natsume
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Kenji Sakimura
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Susumu Tomita
- Department of Neuroscience, Program in Cellular Neuroscience, Neurodegeneration, and Repair, Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Steven J Tavalin
- Department of Pharmacology, University of Tennessee Health Science Center, Memphis, TN 38103, USA
| | - Michael J Higley
- Department of Neuroscience, Program in Cellular Neuroscience, Neurodegeneration, and Repair, Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA.
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19
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Zimmerman AL, Kovatsis EM, Pozsgai RY, Tasnim A, Zhang Q, Ginty DD. Distinct Modes of Presynaptic Inhibition of Cutaneous Afferents and Their Functions in Behavior. Neuron 2019; 102:420-434.e8. [PMID: 30826183 PMCID: PMC6472967 DOI: 10.1016/j.neuron.2019.02.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 12/17/2018] [Accepted: 01/31/2019] [Indexed: 01/10/2023]
Abstract
Presynaptic inhibition (PSI) of primary sensory neurons is implicated in controlling gain and acuity in sensory systems. Here, we define circuit mechanisms and functions of PSI of cutaneous somatosensory neuron inputs to the spinal cord. We observed that PSI can be evoked by different sensory neuron populations and mediated through at least two distinct dorsal horn circuit mechanisms. Low-threshold cutaneous afferents evoke a GABAA-receptor-dependent form of PSI that inhibits similar afferent subtypes, whereas small-diameter afferents predominantly evoke an NMDA-receptor-dependent form of PSI that inhibits large-diameter fibers. Behaviorally, loss of either GABAA receptors (GABAARs) or NMDA receptors (NMDARs) in primary afferents leads to tactile hypersensitivity across skin types, and loss of GABAARs, but not NMDARs, leads to impaired texture discrimination. Post-weaning age loss of either GABAARs or NMDARs in somatosensory neurons causes systemic behavioral abnormalities, revealing critical roles of two distinct modes of PSI of somatosensory afferents in adolescence and throughout adulthood.
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Affiliation(s)
- Amanda L Zimmerman
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Eleni M Kovatsis
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Riana Y Pozsgai
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Aniqa Tasnim
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Qiyu Zhang
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
| | - David D Ginty
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA.
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20
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Holmberg E, Sjöstedt J, Malinina E, Johansson M, Turkmen S, Ragagnin G, Lundqvist A, Löfgren M, Jaukkuri L, Bixo M, Bäckström T. Allopregnanolone involvement in feeding regulation, overeating and obesity. Front Neuroendocrinol 2018; 48:70-77. [PMID: 28694181 DOI: 10.1016/j.yfrne.2017.07.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 07/04/2017] [Accepted: 07/05/2017] [Indexed: 01/19/2023]
Abstract
Obesity is strongly associated with ill health, primarily caused by consumption of excessive calories, and promoted (inter alia) by gamma-amino-butyric-acid (GABA) stimulating food intake by activating GABAA receptors (primarily with α3 and α2 subunits) in the hypothalamic arcuate nucleus and paraventricular nucleus. Allopregnanolone is a potent positive GABAA receptor modulating steroid (GAMS). As reviewed here, elevated allopregnanolone levels are associated with increases in food intake, preferences for energy-rich food, and obesity in humans and other mammals. In women with polycystic ovarian disease, high serum allopregnanolone concentrations are linked to uncontrolled eating, and perturbed sensitivity to allopregnanolone. Increases in weight during pregnancy also correlate with increases in allopregnanolone levels. Moreover, Prader-Willis syndrome is associated with massive overeating, absence of a GABAA receptor (with compensatory >12-, >5- and >1.5-fold increases in α4, γ2, and α1, α3 subunits), and increases in the α4, βx, δ receptor subtype, which is highly sensitive to allopregnanolone. GABA and positive GABA-A receptor modulating steroids like allopregnanolone stimulates food intake and weight gain.
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Affiliation(s)
- E Holmberg
- Umeå Neurosteroid Research Center, Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, SE-901 85 Umeå, Sweden
| | - J Sjöstedt
- Umeå Neurosteroid Research Center, Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, SE-901 85 Umeå, Sweden
| | - E Malinina
- Umeå Neurosteroid Research Center, Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, SE-901 85 Umeå, Sweden
| | - M Johansson
- Umeå Neurosteroid Research Center, Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, SE-901 85 Umeå, Sweden
| | - S Turkmen
- Umeå Neurosteroid Research Center, Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, SE-901 85 Umeå, Sweden
| | - G Ragagnin
- Umeå Neurosteroid Research Center, Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, SE-901 85 Umeå, Sweden
| | - A Lundqvist
- Umeå Neurosteroid Research Center, Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, SE-901 85 Umeå, Sweden
| | - M Löfgren
- Umeå Neurosteroid Research Center, Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, SE-901 85 Umeå, Sweden
| | - L Jaukkuri
- Umeå Neurosteroid Research Center, Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, SE-901 85 Umeå, Sweden
| | - M Bixo
- Umeå Neurosteroid Research Center, Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, SE-901 85 Umeå, Sweden
| | - T Bäckström
- Umeå Neurosteroid Research Center, Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, SE-901 85 Umeå, Sweden.
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21
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Li S, Kumar T P, Joshee S, Kirschstein T, Subburaju S, Khalili JS, Kloepper J, Du C, Elkhal A, Szabó G, Jain RK, Köhling R, Vasudevan A. Endothelial cell-derived GABA signaling modulates neuronal migration and postnatal behavior. Cell Res 2017; 28:221-248. [PMID: 29086765 PMCID: PMC5799810 DOI: 10.1038/cr.2017.135] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 08/06/2017] [Accepted: 09/07/2017] [Indexed: 01/27/2023] Open
Abstract
The cerebral cortex is essential for integration and processing of information
that is required for most behaviors. The exquisitely precise laminar
organization of the cerebral cortex arises during embryonic development when
neurons migrate successively from ventricular zones to coalesce into specific
cortical layers. While radial glia act as guide rails for projection neuron
migration, pre-formed vascular networks provide support and guidance cues for
GABAergic interneuron migration. This study provides novel conceptual and
mechanistic insights into this paradigm of vascular-neuronal interactions,
revealing new mechanisms of GABA and its receptor-mediated signaling via
embryonic forebrain endothelial cells. With the use of two new endothelial cell
specific conditional mouse models of the GABA pathway
(Gabrb3ΔTie2-Cre and
VgatΔTie2-Cre), we show that partial or
complete loss of GABA release from endothelial cells during embryogenesis
results in vascular defects and impairs long-distance migration and positioning
of cortical interneurons. The downstream effects of perturbed endothelial
cell-derived GABA signaling are critical, leading to lasting changes to cortical
circuits and persistent behavioral deficits. Furthermore, we illustrate new
mechanisms of activation of GABA signaling in forebrain endothelial cells that
promotes their migration, angiogenesis and acquisition of blood-brain barrier
properties. Our findings uncover and elucidate a novel endothelial GABA
signaling pathway in the CNS that is distinct from the classical neuronal GABA
signaling pathway and shed new light on the etiology and pathophysiology of
neuropsychiatric diseases, such as autism spectrum disorders, epilepsy, anxiety,
depression and schizophrenia.
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Affiliation(s)
- Suyan Li
- Department of Psychiatry, Harvard Medical School, Boston, MA 02215, USA.,Angiogenesis and Brain Development Laboratory, Division of Basic Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA 02478, USA
| | - Peeyush Kumar T
- Department of Psychiatry, Harvard Medical School, Boston, MA 02215, USA.,Angiogenesis and Brain Development Laboratory, Division of Basic Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA 02478, USA
| | - Sampada Joshee
- Angiogenesis and Brain Development Laboratory, Division of Basic Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA 02478, USA
| | - Timo Kirschstein
- Oscar-Langendorff-Institute of Physiology, Rostock University Medical Center, Gertrudenstrasse 9, 18057 Rostock, Germany
| | - Sivan Subburaju
- Department of Psychiatry, Harvard Medical School, Boston, MA 02215, USA.,Program in Structural and Molecular Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA 02478, USA
| | | | - Jonas Kloepper
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Chuang Du
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02148, USA
| | - Abdallah Elkhal
- Department of Surgery, Harvard Medical School, Boston, MA 02115, USA.,Division of Transplantation, Brigham and Women's Hospital, 221 Longwood Avenue, EBRC 309, Boston, MA 02115, USA
| | - Gábor Szabó
- Laboratory of Molecular Biology and Genetics, Department of Gene Technology and Developmental Neurobiology, Institute of Experimental Medicine, 1083 Budapest, Hungary
| | - Rakesh K Jain
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Rüdiger Köhling
- Oscar-Langendorff-Institute of Physiology, Rostock University Medical Center, Gertrudenstrasse 9, 18057 Rostock, Germany
| | - Anju Vasudevan
- Department of Psychiatry, Harvard Medical School, Boston, MA 02215, USA.,Angiogenesis and Brain Development Laboratory, Division of Basic Neuroscience, McLean Hospital, 115 Mill Street, Belmont, MA 02478, USA
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22
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Rice LJ, Lagopoulos J, Brammer M, Einfeld SL. Reduced gamma-aminobutyric acid is associated with emotional and behavioral problems in Prader-Willi syndrome. Am J Med Genet B Neuropsychiatr Genet 2016; 171:1041-1048. [PMID: 27338833 DOI: 10.1002/ajmg.b.32472] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 06/09/2016] [Indexed: 01/04/2023]
Abstract
Prader-Willi syndrome (PWS) is characterized by infantile hypotonia, hypogonadism, small hands and feet, distinct facial features and usually intellectual impairment. The disorder is associated with severe behavioral disturbances which include hyperphagia leading to morbid obesity, temper outbursts, skin-picking, and compulsive behaviors. While the brain mechanisms that underpin these disturbances are unknown these behaviors suggest a lack of inhibition and thus gamma-aminobutyric acid (GABA), the main inhibitory neurotransmitter may be implicated. In the present study, we investigated in vivo brain GABA and its relationship with emotion and behavior in individuals with PWS. Single voxel proton magnetic resonance spectroscopy (1H-MRS) was performed on 15 individuals with PWS and 15 age- and gender-matched typically developing controls. GABA levels were measured in the parieto-occipital lobe. All other metabolite levels (N-acetyl aspartate, myo-Inositol, glutathione, glutamate, and glutamine + glutamate) were measured in the anterior cingulate cortex (ACC). GABA levels were significantly lower in the participants with PWS who had clinically significant emotional and behavioral problems relative to typically developing control participants and participants with PWS who did not have emotional and behavioral problems within the clinically significant range. GABA levels were negatively correlated with total behavioral problem scores as well as temper outbursts, skin-picking, depression, social relating difficulties, and a tendency to be self-absorbed. Our data suggests that alterations of the GABAergic system may play an important role in aspects of the pathophysiology of PWS. Pathological mechanism found in PWS may be relevant to understanding the control of similar behaviors in the general population. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Lauren J Rice
- Brain and Mind Centre, University of Sydney, Sydney, New South Wales, Australia.,Centre for Disability Research and Policy, University of Sydney, Sydney, New South Wales, Australia
| | - Jim Lagopoulos
- Brain and Mind Centre, University of Sydney, Sydney, New South Wales, Australia.,Queensland Mind and Neuroscience Thompson Institute, University of the Sunshine Coast, Sunshine Coast, Queensland, Australia
| | - Michael Brammer
- Department of Neuroimaging, Institute of Psychiatry, King's College London, London, UK
| | - Stewart L Einfeld
- Brain and Mind Centre, University of Sydney, Sydney, New South Wales, Australia.,Centre for Disability Research and Policy, University of Sydney, Sydney, New South Wales, Australia
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23
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APE1/Ref-1 facilitates recovery of gray and white matter and neurological function after mild stroke injury. Proc Natl Acad Sci U S A 2016; 113:E3558-67. [PMID: 27274063 DOI: 10.1073/pnas.1606226113] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A major hallmark of oxidative DNA damage after stroke is the induction of apurinic/apyrimidinic (AP) sites and strand breaks. To mitigate cell loss after oxidative DNA damage, ischemic cells rapidly engage the base excision-repair proteins, such as the AP site-repairing enzyme AP endonuclease-1 (APE1), also named redox effector factor-1 (Ref-1). Although forced overexpression of APE1 is known to protect against oxidative stress-induced neurodegeneration, there is no concrete evidence demonstrating a role for endogenous APE1 in the long-term recovery of gray and white matter following ischemic injury. To address this gap, we generated, to our knowledge, the first APE1 conditional knockout (cKO) mouse line under control of tamoxifen-dependent Cre recombinase. Using a well-established model of transient focal cerebral ischemia (tFCI), we show that induced deletion of APE1 dramatically enlarged infarct volume and impaired the recovery of sensorimotor and cognitive deficits. APE1 cKO markedly increased postischemic neuronal and oligodendrocyte degeneration, demonstrating that endogenous APE1 preserves both gray and white matter after tFCI. Because white matter repair is instrumental in behavioral recovery after stroke, we also examined the impact of APE1 cKO on demyelination and axonal conduction and discovered that APE1 cKO aggravated myelin loss and impaired neuronal communication following tFCI. Furthermore, APE1 cKO increased AP sites and activated the prodeath signaling proteins, PUMA and PARP1, after tFCI in topographically distinct manners. Our findings provide evidence that endogenous APE1 protects against ischemic infarction in both gray and white matter and facilitates the functional recovery of the central nervous system after mild stroke injury.
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24
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Nunes D, Kuner T. Disinhibition of olfactory bulb granule cells accelerates odour discrimination in mice. Nat Commun 2015; 6:8950. [PMID: 26592770 PMCID: PMC4673882 DOI: 10.1038/ncomms9950] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 10/20/2015] [Indexed: 11/13/2022] Open
Abstract
Granule cells are the dominant cell type of the olfactory bulb inhibiting mitral and tufted cells via dendrodendritic synapses; yet the factors regulating the strength of their inhibitory output, and, therefore, their impact on odour discrimination, remain unknown. Here we show that GABAAR β3-subunits are distributed in a somatodendritic pattern, mostly sparing the large granule cell spines also known as gemmules. Granule cell-selective deletion of β3-subunits nearly abolishes spontaneous and muscimol-induced currents mediated by GABAA receptors in granule cells, yet recurrent inhibition of mitral cells is strongly enhanced. Mice with disinhibited granule cells require less time to discriminate both dissimilar as well as highly similar odourants, while discrimination learning remains unaffected. Hence, granule cells are controlled by an inhibitory drive that in turn tunes mitral cell inhibition. As a consequence, the olfactory bulb inhibitory network adjusts the speed of early sensory processing. How odour discrimination is influenced by granule cells in the olfactory bulb is poorly understood. Here, the authors show that disinhibition of granule cells in mice increases mitral cell inhibition and accelerates odour discrimination time, independent of odour similarity.
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Affiliation(s)
- Daniel Nunes
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, Im Neuenheimer Feld 307, 69120 Heidelberg, Germany
| | - Thomas Kuner
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, Im Neuenheimer Feld 307, 69120 Heidelberg, Germany
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25
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Hua R, Wei M, Zhang C. The complex genetics in autism spectrum disorders. SCIENCE CHINA-LIFE SCIENCES 2015; 58:933-45. [PMID: 26335739 DOI: 10.1007/s11427-015-4893-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Autism spectrum disorders (ASD) are a pervasive neurodevelopmental disease characterized by deficits in social interaction and nonverbal communication, as well as restricted interests and stereotypical behavior. Genetic changes/heritability is one of the major contributing factors, and hundreds to thousands of causative and susceptible genes, copy number variants (CNVs), linkage regions, and microRNAs have been associated with ASD which clearly indicates that ASD is a complex genetic disorder. Here, we will briefly summarize some of the high-confidence genetic changes in ASD and their possible roles in their pathogenesis.
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Affiliation(s)
- Rui Hua
- State Key Laboratory of Membrane Biology, School of Life Sciences; PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - MengPing Wei
- State Key Laboratory of Membrane Biology, School of Life Sciences; PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Chen Zhang
- State Key Laboratory of Membrane Biology, School of Life Sciences; PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China.
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26
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Eaton MM, Cao LQ, Chen Z, Franks NP, Evers AS, Akk G. Mutational Analysis of the Putative High-Affinity Propofol Binding Site in Human β3 Homomeric GABAA Receptors. Mol Pharmacol 2015. [PMID: 26206487 DOI: 10.1124/mol.115.100347] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Propofol is a sedative and anesthetic agent that can both activate GABA(A) receptors and potentiate receptor activation elicited by submaximal concentrations of the transmitter. A recent modeling study of the β3 homomeric GABA(A) receptor postulated a high-affinity propofol binding site in a hydrophobic pocket in the middle of a triangular cleft lined by the M1 and M2 membrane-spanning domains of one subunit and the M2 domain of the neighboring subunit. The goal of the present study was to gain functional evidence for the involvement of this pocket in the actions of propofol. Human β3 and α1β3 receptors were expressed in Xenopus oocytes, and the effects of substitutions of selected residues were probed on channel activation by propofol and pentobarbital. The data demonstrate the vital role of the β3(Y143), β3(F221), β3(Q224), and β3(T266) residues in the actions of propofol but not pentobarbital in β3 receptors. The effects of β3(Y143W) and β3(Q224W) on activation by propofol are likely steric because propofol analogs with less bulky ortho substituents activated both wild-type and mutant receptors. The T266W mutation removed activation by propofol in β3 homomeric receptors; however, this mutation alone or in combination with a homologous mutation (I271W) in the α1 subunit had almost no effect on activation properties in α1β3 heteromeric receptors. We hypothesize that heteromeric α1β3 receptors can be activated by propofol interactions with β3-β3, α1-β3, and β3-α1 interfaces, but the exact locations of the binding site and/or nature of interactions vary in different classes of interfaces.
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Affiliation(s)
- Megan M Eaton
- Department of Anesthesiology (M.M.E., L.Q.C., Z.C., A.S.E., G.A.) and the Taylor Family Institute for Innovative Psychiatric Research (Z.C., A.S.E., G.A.), Washington University School of Medicine, St. Louis, Missouri; and Department of Life Sciences, Imperial College London, South Kensington, United Kingdom (N.P.F.)
| | - Lily Q Cao
- Department of Anesthesiology (M.M.E., L.Q.C., Z.C., A.S.E., G.A.) and the Taylor Family Institute for Innovative Psychiatric Research (Z.C., A.S.E., G.A.), Washington University School of Medicine, St. Louis, Missouri; and Department of Life Sciences, Imperial College London, South Kensington, United Kingdom (N.P.F.)
| | - Ziwei Chen
- Department of Anesthesiology (M.M.E., L.Q.C., Z.C., A.S.E., G.A.) and the Taylor Family Institute for Innovative Psychiatric Research (Z.C., A.S.E., G.A.), Washington University School of Medicine, St. Louis, Missouri; and Department of Life Sciences, Imperial College London, South Kensington, United Kingdom (N.P.F.)
| | - Nicholas P Franks
- Department of Anesthesiology (M.M.E., L.Q.C., Z.C., A.S.E., G.A.) and the Taylor Family Institute for Innovative Psychiatric Research (Z.C., A.S.E., G.A.), Washington University School of Medicine, St. Louis, Missouri; and Department of Life Sciences, Imperial College London, South Kensington, United Kingdom (N.P.F.)
| | - Alex S Evers
- Department of Anesthesiology (M.M.E., L.Q.C., Z.C., A.S.E., G.A.) and the Taylor Family Institute for Innovative Psychiatric Research (Z.C., A.S.E., G.A.), Washington University School of Medicine, St. Louis, Missouri; and Department of Life Sciences, Imperial College London, South Kensington, United Kingdom (N.P.F.)
| | - Gustav Akk
- Department of Anesthesiology (M.M.E., L.Q.C., Z.C., A.S.E., G.A.) and the Taylor Family Institute for Innovative Psychiatric Research (Z.C., A.S.E., G.A.), Washington University School of Medicine, St. Louis, Missouri; and Department of Life Sciences, Imperial College London, South Kensington, United Kingdom (N.P.F.)
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27
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Pyramidal cell selective ablation of N-methyl-D-aspartate receptor 1 causes increase in cellular and network excitability. Biol Psychiatry 2015; 77:556-68. [PMID: 25156700 PMCID: PMC4297754 DOI: 10.1016/j.biopsych.2014.06.026] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 06/05/2014] [Accepted: 06/22/2014] [Indexed: 12/15/2022]
Abstract
BACKGROUND Neuronal activity at gamma frequency is impaired in schizophrenia (SZ) and is considered critical for cognitive performance. Such impairments are thought to be due to reduced N-methyl-D-aspartate receptor (NMDAR)-mediated inhibition from parvalbumin interneurons, rather than a direct role of impaired NMDAR signaling on pyramidal neurons. However, recent studies suggest a direct role of pyramidal neurons in regulating gamma oscillations. In particular, a computational model has been proposed in which phasic currents from pyramidal cells could drive synchronized feedback inhibition from interneurons. As such, impairments in pyramidal neuron activity could lead to abnormal gamma oscillations. However, this computational model has not been tested experimentally and the molecular mechanisms underlying pyramidal neuron dysfunction in SZ remain unclear. METHODS In the present study, we tested the hypothesis that SZ-related phenotypes could arise from reduced NMDAR signaling in pyramidal neurons using forebrain pyramidal neuron specific NMDA receptor 1 knockout mice. RESULTS The mice displayed increased baseline gamma power, as well as sociocognitive impairments. These phenotypes were associated with increased pyramidal cell excitability due to changes in inherent membrane properties. Interestingly, mutant mice showed decreased expression of GIRK2 channels, which has been linked to increased neuronal excitability. CONCLUSIONS Our data demonstrate for the first time that NMDAR hypofunction in pyramidal cells is sufficient to cause electrophysiological, molecular, neuropathological, and behavioral changes related to SZ.
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28
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Fritschy JM. Significance of GABAA Receptor Heterogeneity. DIVERSITY AND FUNCTIONS OF GABA RECEPTORS: A TRIBUTE TO HANNS MÖHLER, PART B 2015; 73:13-39. [DOI: 10.1016/bs.apha.2014.11.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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29
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Chen JTC, Guo D, Campanelli D, Frattini F, Mayer F, Zhou L, Kuner R, Heppenstall PA, Knipper M, Hu J. Presynaptic GABAergic inhibition regulated by BDNF contributes to neuropathic pain induction. Nat Commun 2014; 5:5331. [PMID: 25354791 PMCID: PMC4220496 DOI: 10.1038/ncomms6331] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 09/22/2014] [Indexed: 01/21/2023] Open
Abstract
The gate control theory proposes the importance of both pre- and post-synaptic inhibition in processing pain signal in the spinal cord. However, although postsynaptic disinhibition caused by brain-derived neurotrophic factor (BDNF) has been proved as a crucial mechanism underlying neuropathic pain, the function of presynaptic inhibition in acute and neuropathic pain remains elusive. Here we show that a transient shift in the reversal potential (EGABA) together with a decline in the conductance of presynaptic GABAA receptor result in a reduction of presynaptic inhibition after nerve injury. BDNF mimics, whereas blockade of BDNF signalling reverses, the alteration in GABAA receptor function and the neuropathic pain syndrome. Finally, genetic disruption of presynaptic inhibition leads to spontaneous development of behavioural hypersensitivity, which cannot be further sensitized by nerve lesions or BDNF. Our results reveal a novel effect of BDNF on presynaptic GABAergic inhibition after nerve injury and may represent new strategy for treating neuropathic pain. Disinhibition of neural activity in the spinal cord is implicated in neuropathic pain. Chen et al. show that disinhibition of neural activity arises from a shift in reversal potential of GABA and a decrease in the conductance of presynaptic GABA, which are both regulated by brain-derived neurotrophic factor.
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Affiliation(s)
| | - Da Guo
- Centre for Integrative Neuroscience, Otfried-Mueller-Strasse 25, 72076 Tübingen, Germany
| | - Dario Campanelli
- 1] Centre for Integrative Neuroscience, Otfried-Mueller-Strasse 25, 72076 Tübingen, Germany [2] Hearing Research Centre, Elfriede Aulhornstrasse 5, 72076 Tübingen, Germany
| | - Flavia Frattini
- Centre for Integrative Neuroscience, Otfried-Mueller-Strasse 25, 72076 Tübingen, Germany
| | - Florian Mayer
- Centre for Integrative Neuroscience, Otfried-Mueller-Strasse 25, 72076 Tübingen, Germany
| | - Luming Zhou
- Laboratory for NeuroRegeneration and Repair, Center for Neurology, Hertie Institute for Clinical Brain Research, 72076 Tübingen, Germany
| | - Rohini Kuner
- Pharmacology Institute, University of Heidelberg, Im Neuenheimer Feld 584, 69120 Heidelberg, Germany
| | - Paul A Heppenstall
- Mouse Biology Unit, European Molecular Biology Laboratory (EMBL), Via Ramarini 32, 00016 Monterotondo, Italy
| | - Marlies Knipper
- Hearing Research Centre, Elfriede Aulhornstrasse 5, 72076 Tübingen, Germany
| | - Jing Hu
- Centre for Integrative Neuroscience, Otfried-Mueller-Strasse 25, 72076 Tübingen, Germany
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30
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Genetic ablation of VIAAT in glycinergic neurons causes a severe respiratory phenotype and perinatal death. Brain Struct Funct 2014; 220:2835-49. [PMID: 25027639 DOI: 10.1007/s00429-014-0829-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 06/21/2014] [Indexed: 12/14/2022]
Abstract
Both glycinergic and GABAergic neurons require the vesicular inhibitory amino acid transporter (VIAAT) for synaptic vesicle filling. Presynaptic GABA concentrations are determined by the GABA-synthesizing enzymes glutamate decarboxylase (GAD)65 and GAD67, whereas the presynaptic glycine content depends on the plasma membrane glycine transporter 2 (GlyT2). Although severely impaired, glycinergic transmission is not completely absent in GlyT2-knockout mice, suggesting that other routes of glycine uptake or de novo synthesis of glycine exist in presynaptic terminals. To investigate the consequences of a complete loss of glycinergic transmission, we generated a mouse line with a conditional ablation of VIAAT in glycinergic neurons by crossing mice with loxP-flanked VIAAT alleles with a GlyT2-Cre transgenic mouse line. Interestingly, conditional VIAAT knockout (VIAAT cKO) mice were not viable at birth. In addition to the dominant respiratory failure, VIAAT cKO showed an umbilical hernia and a cleft palate. Immunohistochemistry revealed an almost complete depletion of VIAAT in the brainstem. Electrophysiology revealed the absence of both spontaneous glycinergic and GABAergic inhibitory postsynaptic currents from hypoglossal motoneurons. Our results demonstrate that the deletion of VIAAT in GlyT2-Cre expressing neurons also strongly affects GABAergic transmission and suggest a large overlap of the glycinergic and the GABAergic neuron population during early development in the caudal parts of the brain.
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31
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Fritschy JM, Panzanelli P. GABAAreceptors and plasticity of inhibitory neurotransmission in the central nervous system. Eur J Neurosci 2014; 39:1845-65. [DOI: 10.1111/ejn.12534] [Citation(s) in RCA: 144] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2014] [Revised: 01/29/2014] [Accepted: 01/29/2014] [Indexed: 12/11/2022]
Affiliation(s)
- Jean-Marc Fritschy
- Institute of Pharmacology and Toxicology; University of Zurich; Winterthurerstrasse 190 8057 Zurich Switzerland
- Neuroscience Center Zurich; University of Zurich and ETH; Zurich Switzerland
| | - Patrizia Panzanelli
- Department of Neuroscience Rita Levi Montalcini; University of Turin; Turin Italy
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32
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Lee V, Maguire J. The impact of tonic GABAA receptor-mediated inhibition on neuronal excitability varies across brain region and cell type. Front Neural Circuits 2014; 8:3. [PMID: 24550784 PMCID: PMC3909947 DOI: 10.3389/fncir.2014.00003] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 01/08/2014] [Indexed: 01/19/2023] Open
Abstract
The diversity of GABAA receptor (GABAAR) subunits and the numerous configurations during subunit assembly give rise to a variety of receptors with different functional properties. This heterogeneity results in variations in GABAergic conductances across numerous brain regions and cell types. Phasic inhibition is mediated by synaptically-localized receptors with a low affinity for GABA and results in a transient, rapidly desensitizing GABAergic conductance; whereas, tonic inhibition is mediated by extrasynaptic receptors with a high affinity for GABA and results in a persistent GABAergic conductance. The specific functions of tonic versus phasic GABAergic inhibition in different cell types and the impact on specific neural circuits are only beginning to be unraveled. Here we review the diversity in the magnitude of tonic GABAergic inhibition in various brain regions and cell types, and highlight the impact on neuronal excitability in different neuronal circuits. Further, we discuss the relevance of tonic inhibition in various physiological and pathological contexts as well as the potential of targeting these receptor subtypes for treatment of diseases, such as epilepsy.
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Affiliation(s)
- Vallent Lee
- Medical Scientist Training Program and Graduate Program in Neuroscience, Sackler School of Graduate Biomedical Sciences, Tufts University Boston, MA, USA
| | - Jamie Maguire
- Department of Neuroscience, Tufts University School of Medicine Boston, MA, USA
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33
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Luo R, Partridge JG, Vicini S. Distinct roles of synaptic and extrasynaptic GABAAreceptors in striatal inhibition dynamics. Front Neural Circuits 2013; 7:186. [PMID: 24324406 PMCID: PMC3840641 DOI: 10.3389/fncir.2013.00186] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 11/02/2013] [Indexed: 01/15/2023] Open
Abstract
Striatonigral and striatopallidal projecting medium spiny neurons (MSNs) express dopamine D1 (D1+) and D2 receptors (D2+), respectively. Both classes receive extensive GABAergic input via expression of synaptic, perisynaptic, and extrasynaptic GABAA receptors. The activation patterns of different presynaptic GABAergic neurons produce transient and sustained GABAA receptor-mediated conductance that fulfill distinct physiological roles. We performed single and dual whole cell recordings from striatal neurons in mice expressing fluorescent proteins in interneurons and MSNs. We report specific inhibitory dynamics produced by distinct activation patterns of presynaptic GABAergic neurons as source of synaptic, perisynaptic, and extrasynaptic inhibition. Synaptic GABAA receptors in MSNs contain the α2, γ2, and a β subunit. In addition, there is evidence for the developmental increase of the α1 subunit that contributes to faster inhibitory post-synaptic current (IPSC). Tonic GABAergic currents in MSNs from adult mice are carried by extrasynaptic receptors containing the α4 and δ subunit, while in younger mice this current is mediated by receptors that contain the α5 subunit. Both forms of tonic currents are differentially expressed in D1+ and D2+ MSNs. This study extends these findings by relating presynaptic activation with pharmacological analysis of inhibitory conductance in mice where the β3 subunit is conditionally removed in fluorescently labeled D2+ MSNs and in mice with global deletion of the δ subunit. Our results show that responses to low doses of gaboxadol (2 μM), a GABAA receptor agonist with preference to δ subunit, are abolished in the δ but not the β3 subunit knock out mice. This suggests that the β3 subunit is not a component of the adult extrasynaptic receptor pool, in contrast to what has been shown for tonic current in young mice. Deletion of the β3 subunit from D2+ MSNs however, removed slow spontaneous IPSCs, implicating its role in mediating synaptic input from striatal neurogliaform interneurons.
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Affiliation(s)
- Ruixi Luo
- Department of Pharmacology and Physiology, Georgetown University School of Medicine Washington, DC, USA
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Iyer SV, Chandra D, Homanics GE. GABAA-R α4 subunits are required for the low dose locomotor stimulatory effect of alphaxalone, but not for several other behavioral responses to alphaxalone, etomidate or propofol. Neurochem Res 2013; 39:1048-56. [PMID: 24062179 DOI: 10.1007/s11064-013-1148-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 08/26/2013] [Accepted: 08/30/2013] [Indexed: 10/26/2022]
Abstract
γ-Aminobutyric acid type A receptors (GABAA-Rs) are considered to be the primary molecular targets of injectable anesthetics such as propofol, etomidate and the neurosteriod, alphaxalone. A number of studies have sought to understand the specific GABAA-R subtypes involved in the mechanism of action of these three drugs. Here, we investigated the role of α4-subunit containing GABAA-Rs in the neurobehavioral responses to these drugs. Drug responses in α4 subunit knockout (KO) mice were compared to wild type (WT) littermate controls. While etomidate and propofol are currently used as injectable anesthetics, alphaxalone belongs to the class of neurosteroid drugs having anesthetic effects. Low dose effects of etomidate and alphaxalone were studied using an open field assay. The moderate and high dose effects of all three anesthetics were measured using the rotarod and loss of righting reflex assays, respectively. The locomotor stimulatory effect of alphaxalone was reduced significantly in α4 KO mice compared to WT controls. Neither the low dose sedating effect of etomidate, nor the moderate/high dose effect of any of the drugs differed between genotypes. These results suggest that α4 subunit-containing GABAA-Rs are required for the low dose, locomotor stimulatory effect of alphaxalone but are not required for the sedating effect of etomidate or the moderate/high dose effects of etomidate, propofol or alphaxalone on motor ataxia and loss of righting reflex.
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Affiliation(s)
- Sangeetha V Iyer
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
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Chang C, Yeh S, Lee SO, Chang TM. Androgen receptor (AR) pathophysiological roles in androgen-related diseases in skin, bone/muscle, metabolic syndrome and neuron/immune systems: lessons learned from mice lacking AR in specific cells. NUCLEAR RECEPTOR SIGNALING 2013; 11:e001. [PMID: 24653668 PMCID: PMC3960937 DOI: 10.1621/nrs.11001] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 05/28/2013] [Indexed: 12/19/2022]
Abstract
The androgen receptor (AR) is expressed ubiquitously and plays a variety of roles in a vast number of physiological and pathophysiological processes. Recent studies of AR knockout (ARKO) mouse models, particularly the cell type- or tissue-specific ARKO models, have uncovered many AR cell type- or tissue-specific pathophysiological roles in mice, which otherwise would not be delineated from conventional castration and androgen insensitivity syndrome studies. Thus, the AR in various specific cell types plays pivotal roles in production and maturation of immune cells, bone mineralization, and muscle growth. In metabolism, the ARs in brain, particularly in the hypothalamus, and the liver appear to participate in regulation of insulin sensitivity and glucose homeostasis. The AR also plays key roles in cutaneous wound healing and cardiovascular diseases, including atherosclerosis and abdominal aortic aneurysm. This article will discuss the results obtained from the total, cell type-, or tissue-specific ARKO models. The understanding of AR cell type- or tissue-specific physiological and pathophysiological roles using these in
vivo mouse models will provide useful information in uncovering AR roles in humans and eventually help us to develop better therapies via targeting the AR or its downstream signaling molecules to combat androgen/AR-related diseases.
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Affiliation(s)
- Chawnshang Chang
- George Whipple Lab for Cancer Research, Departments of Pathology, Urology, Radiation Oncology, and the Wilmot Cancer Center, University of Rochester Medical Center, Rochester, New York, USA (CC, SY, SOL, T-MC) and Sex Hormone Research Center, China Medical University/Hospital, Taichung, Taiwan (CC)
| | - Shuyuan Yeh
- George Whipple Lab for Cancer Research, Departments of Pathology, Urology, Radiation Oncology, and the Wilmot Cancer Center, University of Rochester Medical Center, Rochester, New York, USA (CC, SY, SOL, T-MC) and Sex Hormone Research Center, China Medical University/Hospital, Taichung, Taiwan (CC)
| | - Soo Ok Lee
- George Whipple Lab for Cancer Research, Departments of Pathology, Urology, Radiation Oncology, and the Wilmot Cancer Center, University of Rochester Medical Center, Rochester, New York, USA (CC, SY, SOL, T-MC) and Sex Hormone Research Center, China Medical University/Hospital, Taichung, Taiwan (CC)
| | - Ta-Min Chang
- George Whipple Lab for Cancer Research, Departments of Pathology, Urology, Radiation Oncology, and the Wilmot Cancer Center, University of Rochester Medical Center, Rochester, New York, USA (CC, SY, SOL, T-MC) and Sex Hormone Research Center, China Medical University/Hospital, Taichung, Taiwan (CC)
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Isoflurane enhances both fast and slow synaptic inhibition in the hippocampus at amnestic concentrations. Anesthesiology 2012; 116:816-23. [PMID: 22343472 DOI: 10.1097/aln.0b013e31824be0e3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Inhibition mediated by γ-aminobutyric acid type A (GABA A) receptors has long been considered an important target for a variety of general anesthetics. In the hippocampus, two types of phasic GABA A receptor-mediated inhibition coexist: GABA A,fast, which is expressed primarily at peri-somatic sites, and GABAA,slow, which is expressed primarily in the dendrites. Their spatial segregation suggests distinct functions: GABA A,slow may control plasticity of dendritic synapses, whereas GABA A,fast controls action potential initiation at the soma. We examined modulation of GABA A,fast and GABA A,slow inhibition by isoflurane at amnesic concentrations, and compared it with modulation by behaviorally equivalent doses of the GABA A receptor-selective drug etomidate. METHODS Whole cell recordings were obtained from pyramidal cells in organotypic hippocampal cultures prepared from C57BL/6 × 129/SvJ F1 hybrid mice. GABA A receptor-mediated currents were isolated using glutamate receptor antagonists. GABAA,slow currents were evoked by electrical stimulation in the stratum lacunosum-moleculare. Miniature GABA A,fast currents were recorded in the presence of tetrodotoxin. RESULTS 100 μM isoflurane (approximately EC50,amnesia) slowed fast- and slow-inhibitory postsynaptic current decay by approximately 25%. Higher concentrations, up to 400 μM, produced proportionally greater effects without altering current amplitudes. The effects on GABA A,slow were approximately one-half those produced by equi-amnesic concentrations of etomidate. CONCLUSIONS Isoflurane enhances both types of phasic GABA A receptor-mediated inhibition to similar degrees at amnesic concentrations. This pattern differs from etomidate, which at low concentrations selectively enhances slow inhibition. These effects of isoflurane are sufficiently large that they may contribute substantially to its suppression of hippocampal learning and memory.
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All-<I>trans</I> Retinoic Acid Promotes Cell Apoptosis Through Gamma Amino Butyric Acid Pathway in Murine Embryonic Palate Mesenchymal Cells. PROG BIOCHEM BIOPHYS 2012. [DOI: 10.3724/sp.j.1206.2011.00199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Rout U, Abdul-Rahman OA, Dhossche DM. An immunological basis of hyperphagia driven by GABAergic dysfunction in Prader-Willi Syndrome. Med Hypotheses 2012; 78:462-4. [PMID: 22289342 DOI: 10.1016/j.mehy.2011.12.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Accepted: 12/27/2011] [Indexed: 10/14/2022]
Abstract
Impaired immune function is increasingly seen as a core element of various neurological, psychiatric, and developmental disorders but has not yet been investigated in subjects with Prader-Willi Syndrome. We hypothesize that the emergence and the progression of PWS may be regulated by immune dysfunction involving auto-antibodies and miRNA driven by GABAergic dysfunction. Future research testing this hypothesis is discussed.
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Affiliation(s)
- Ujjwal Rout
- Department of Surgery, Physiology and Biophysics, The University of Mississippi Medical Center, Jackson, MS 39216-4505, USA.
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Attenuating GABA(A) receptor signaling in dopamine neurons selectively enhances reward learning and alters risk preference in mice. J Neurosci 2012; 31:17103-12. [PMID: 22114279 DOI: 10.1523/jneurosci.1715-11.2011] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Phasic dopamine (DA) transmission encodes the value of reward-predictive stimuli and influences both learning and decision-making. Altered DA signaling is associated with psychiatric conditions characterized by risky choices such as pathological gambling. These observations highlight the importance of understanding how DA neuron activity is modulated. While excitatory drive onto DA neurons is critical for generating phasic DA responses, emerging evidence suggests that inhibitory signaling also modulates these responses. To address the functional importance of inhibitory signaling in DA neurons, we generated mice lacking the β3 subunit of the GABA(A) receptor specifically in DA neurons (β3-KO mice) and examined their behavior in tasks that assessed appetitive learning, aversive learning, and risk preference. DA neurons in midbrain slices from β3-KO mice exhibited attenuated GABA-evoked IPSCs. Furthermore, electrical stimulation of excitatory afferents to DA neurons elicited more DA release in the nucleus accumbens of β3-KO mice as measured by fast-scan cyclic voltammetry. β3-KO mice were more active than controls when given morphine, which correlated with potential compensatory upregulation of GABAergic tone onto DA neurons. β3-KO mice learned faster in two food-reinforced learning paradigms, but extinguished their learned behavior normally. Enhanced learning was specific for appetitive tasks, as aversive learning was unaffected in β3-KO mice. Finally, we found that β3-KO mice had enhanced risk preference in a probabilistic selection task that required mice to choose between a small certain reward and a larger uncertain reward. Collectively, these findings identify a selective role for GABA(A) signaling in DA neurons in appetitive learning and decision-making.
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Rau V, Oh I, Liao M, Bodarky C, Fanselow MS, Homanics GE, Sonner JM, Eger EI. Gamma-aminobutyric acid type A receptor β3 subunit forebrain-specific knockout mice are resistant to the amnestic effect of isoflurane. Anesth Analg 2011; 113:500-4. [PMID: 21813630 DOI: 10.1213/ane.0b013e3182273aff] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND β3 containing γ-aminobutyric acid type A receptors (GABA(A)-Rs) mediate behavioral end points of IV anesthetics such as immobility and hypnosis. A knockout mouse with targeted forebrain deletion of the β3 subunit of the GABA(A)-R shows reduced sensitivity to the hypnotic effect of etomidate, as measured by the loss of righting reflex. The end points of amnesia and immobility produced by an inhaled anesthetic have yet to be evaluated in this conditional knockout. METHODS We assessed forebrain selective β3 conditional knockout mice and their littermate controls for conditional fear to evaluate amnesia and MAC, the minimum alveolar concentration of inhaled anesthetic necessary to produce immobility in response to noxious stimulation, to assess immobility. Suppression of conditional fear was assessed for etomidate and isoflurane, and MAC was assessed for isoflurane. RESULTS Etomidate equally suppressed conditional fear for both genotypes. The knockout showed resistance to the suppression of conditional fear produced by isoflurane in comparison with control littermates. Controls and knockouts did not differ in isoflurane MAC values. CONCLUSIONS These results suggest that β3 containing GABA(A)-Rs in the forebrain contribute to hippocampal-dependent memory suppressed by isoflurane, but not etomidate.
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Affiliation(s)
- Vinuta Rau
- Department of Anesthesia, S-455, University of California San Francisco, San Francisco, CA 94143-0464, USA.
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Janssen MJ, Yasuda RP, Vicini S. GABA(A) Receptor β3 Subunit Expression Regulates Tonic Current in Developing Striatopallidal Medium Spiny Neurons. Front Cell Neurosci 2011; 5:15. [PMID: 21847370 PMCID: PMC3147169 DOI: 10.3389/fncel.2011.00015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 07/09/2011] [Indexed: 11/13/2022] Open
Abstract
The striatum is a key structure for movement control, but the mechanisms that dictate the output of distinct subpopulations of medium spiny projection neurons (MSNs), striatonigral projecting and dopamine D1 receptor- (D1+) or striatopallidal projecting and dopamine D2 receptor- (D2+) expressing neurons, remains poorly understood. GABA-mediated tonic inhibition largely controls neuronal excitability and action potential firing rates, and we previously suggested with pharmacological analysis that the GABA(A) receptor β3 subunit plays a large role in the basal tonic current seen in D2+ MSNs from young mice (Ade et al., 2008; Janssen et al., 2009). In this study, we demonstrated the essential role of the β3 GABA(A) receptor subunit in mediating MSN tonic currents using conditional β3 subunit knock-out (β3f/f(Drd2)) mice. Cre-lox genetics were used to generate mice where Cre recombinase was expressed under the D2 receptor (Drd2) promoter. We show that while the wild-type MSN tonic current pattern demonstrates a high degree of variability, tonic current patterns from β3f/f(Drd2) mice are narrow, suggesting that the β3 subunit is essential to striatal MSN GABA-mediated tonic current. Our data also suggest that a distinct population of synaptic receptors upregulate due to β3 subunit removal. Further, deletion of this subunit significantly decreases the D2+ MSN excitability. These results offer insight for target mechanisms in Parkinson's disease, where symptoms arise due to the imbalance in striatal D1+ and D2+ MSN excitability and output.
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Affiliation(s)
- Megan J Janssen
- Department of Pharmacology and Physiology, Georgetown University School of Medicine Washington, DC, USA
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Takumi T. The neurobiology of mouse models syntenic to human chromosome 15q. J Neurodev Disord 2011; 3:270-81. [PMID: 21789598 PMCID: PMC3261275 DOI: 10.1007/s11689-011-9088-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Accepted: 07/12/2011] [Indexed: 11/26/2022] Open
Abstract
Autism is a neurodevelopmental disorder that manifests in childhood as social behavioral abnormalities, such as abnormal social interaction, impaired communication, and restricted interest or behavior. Of the known causes of autism, duplication of human chromosome 15q11–q13 is the most frequently associated cytogenetic abnormality. Chromosome 15q11–q13 is also known to include imprinting genes. In terms of neuroscience, it contains interesting genes such as Necdin, Ube3a, and a cluster of GABAA subunits as well as huge clusters of non-coding RNAs (small nucleolar RNAs, snoRNAs). Phenotypic analyses of mice genetically or chromosomally engineered for each gene or their clusters on a region of mouse chromosome seven syntenic to human 15q11–q13 indicate that this region may be involved in social behavior, serotonin metabolism, and weight control. Further studies using these models will provide important clues to the pathophysiology of autism. This review overviews phenotypes of mouse models of genes in 15q11–q13 and their relationships to autism.
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Affiliation(s)
- Toru Takumi
- Laboratory of Integrative Bioscience, Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Minami, Hiroshima, 734-8553, Japan,
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Kuroda KO, Tachikawa K, Yoshida S, Tsuneoka Y, Numan M. Neuromolecular basis of parental behavior in laboratory mice and rats: with special emphasis on technical issues of using mouse genetics. Prog Neuropsychopharmacol Biol Psychiatry 2011; 35:1205-31. [PMID: 21338647 DOI: 10.1016/j.pnpbp.2011.02.008] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 02/14/2011] [Accepted: 02/14/2011] [Indexed: 01/07/2023]
Abstract
To support the well-being of the parent-infant relationship, the neuromolecular mechanisms of parental behaviors should be clarified. From neuroanatomical analyses in laboratory rats, the medial preoptic area (MPOA) has been shown to be of critical importance in parental retrieving behavior. More recently, various gene-targeted mouse strains have been found to be defective in different aspects of parental behaviors, contributing to the identification of molecules and signaling pathways required for the behavior. Therefore, the neuromolecular basis of "mother love" is now a fully approachable research field in modern molecular neuroscience. In this review, we will provide a summary of the required brain areas and gene for parental behavior in laboratory mice (Mus musculus) and rats (Rattus norvegicus). Basic protocols and technical considerations on studying the mechanism of parental behavior using genetically-engineered mouse strains will also be presented.
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Affiliation(s)
- Kumi O Kuroda
- Unit for Affiliative Social Behavior, RIKEN Brain Science Institute, Saitama 351-0198, Japan.
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Alò R, Avolio E, Di Vito A, Carelli A, Facciolo RM, Canonaco M. Distinct α subunit variations of the hypothalamic GABAA receptor triplets (αβγ) are linked to hibernating state in hamsters. BMC Neurosci 2010; 11:111. [PMID: 20815943 PMCID: PMC2944354 DOI: 10.1186/1471-2202-11-111] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Accepted: 09/06/2010] [Indexed: 12/01/2022] Open
Abstract
Background The structural arrangement of the γ-aminobutyric acid type A receptor (GABAAR) is known to be crucial for the maintenance of cerebral-dependent homeostatic mechanisms during the promotion of highly adaptive neurophysiological events of the permissive hibernating rodent, i.e the Syrian golden hamster. In this study, in vitro quantitative autoradiography and in situ hybridization were assessed in major hypothalamic nuclei. Reverse Transcription Reaction-Polymerase chain reaction (RT-PCR) tests were performed for specific GABAAR receptor subunit gene primers synthases of non-hibernating (NHIB) and hibernating (HIB) hamsters. Attempts were made to identify the type of αβγ subunit combinations operating during the switching ON/OFF of neuronal activities in some hypothalamic nuclei of hibernators. Results Both autoradiography and molecular analysis supplied distinct expression patterns of all α subunits considered as shown by a strong (p < 0.01) prevalence of α1 ratio (over total α subunits considered in the present study) in the medial preoptic area (MPOA) and arcuate nucleus (Arc) of NHIBs with respect to HIBs. At the same time α2 subunit levels proved to be typical of periventricular nucleus (Pe) and Arc of HIB, while strong α4 expression levels were detected during awakening state in the key circadian hypothalamic station, i.e. the suprachiasmatic nucleus (Sch; 60%). Regarding the other two subunits (β and γ), elevated β3 and γ3 mRNAs levels mostly characterized MPOA of HIBs, while prevalently elevated expression concentrations of the same subunits were also typical of Sch, even though this time during the awakening state. In the case of Arc, notably elevated levels were obtained for β3 and γ2 during hibernating conditions. Conclusion We conclude that different αβγ subunits are operating as major elements either at the onset of torpor or during induction of the arousal state in the Syrian golden hamster. The identification of a brain regional distribution pattern of distinct GABAAR subunit combinations may prove to be very useful for highlighting GABAergic mechanisms functioning at least during the different physiological states of hibernators and this may have interesting therapeutic bearings on neurological sleeping disorders.
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Affiliation(s)
- Raffaella Alò
- Comparative Neuroanatomy Laboratory, Ecology Department, University of Calabria, Ponte Pietro Bucci, 87030 Arcavacata di Rende, Cosenza, Italy.
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Oh WJ, Westmoreland JJ, Summers R, Condie BG. Cleft palate is caused by CNS dysfunction in Gad1 and Viaat knockout mice. PLoS One 2010; 5:e9758. [PMID: 20333300 PMCID: PMC2841638 DOI: 10.1371/journal.pone.0009758] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Accepted: 03/01/2010] [Indexed: 12/22/2022] Open
Abstract
Background Previous studies have shown that disruption of GABA signaling in mice via mutations in the Gad1, Gabrb3 or Viaat genes leads to the development of non-neural developmental defects such as cleft palate. Studies of the Gabrb3 and Gad1 mutant mice have suggested that GABA function could be required either in the central nervous system or in the palate itself for normal palatogenesis. Methodology/Principal Findings To further examine the role of GABA signaling in palatogenesis we used three independent experimental approaches to test whether Gad1 or Viaat function is required in the fetal CNS for normal palate development. We used oral explant cultures to demonstrate that the Gad1 and Viaat mutant palates were able to undergo palatogenesis in culture, suggesting that there is no defect in the palate tissue itself in these mice. In a second series of experiments we found that the GABAA receptor agonist muscimol could rescue the cleft palate phenotype in Gad1 and Viaat mutant embryos. This suggested that normal multimeric GABAA receptors in the CNS were necessary for normal palatogenesis. In addition, we showed that CNS-specific inactivation of Gad1 was sufficient to disrupt palate development. Conclusions/Significance Our results are consistent with a role for Gad1 and Viaat in the central nervous system for normal development of the palate. We suggest that the alterations in GABA signaling lead to non-neural defects such as cleft palate as a secondary effect due to alterations in or elimination of fetal movements.
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Affiliation(s)
- Won-Jong Oh
- Developmental Biology Group, Department of Genetics, University of Georgia, Athens, Georgia, United States of America
- Institute of Molecular Medicine, Medical College of Georgia, Augusta, Georgia, United States of America
| | - Joby J. Westmoreland
- Institute of Molecular Medicine, Medical College of Georgia, Augusta, Georgia, United States of America
| | - Ryan Summers
- Developmental Biology Group, Department of Genetics, University of Georgia, Athens, Georgia, United States of America
| | - Brian G. Condie
- Developmental Biology Group, Department of Genetics, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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Stein D, Chetty M, Rho JM. A "happy" toddler presenting with sudden, life-threatening seizures. Semin Pediatr Neurol 2010; 17:35-8. [PMID: 20434691 DOI: 10.1016/j.spen.2010.02.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Angelman syndrome is often associated with medically refractory epilepsy. Here, we report the case of a young girl with Angelman syndrome who experienced frequent and prolonged atonic seizures associated with dysautonomia and was unresponsive to multiple antiepileptic drugs, but who responded dramatically to the ketogenic diet. Clinicians are encouraged to consider the ketogenic diet early in the treatment course of patients with Angelman syndrome.
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Affiliation(s)
- Diane Stein
- Pediatric Neurology, Southern California Permanente Medical Group, Kaiser Permanente Hospital Bellflower, Bellflower, CA, USA
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Pape JR, Bertrand SS, Lafon P, Odessa MF, Chaigniau M, Stiles JK, Garret M. Expression of GABA(A) receptor alpha3-, theta-, and epsilon-subunit mRNAs during rat CNS development and immunolocalization of the epsilon subunit in developing postnatal spinal cord. Neuroscience 2009; 160:85-96. [PMID: 19249336 DOI: 10.1016/j.neuroscience.2009.02.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Revised: 02/03/2009] [Accepted: 02/19/2009] [Indexed: 12/13/2022]
Abstract
Ionotropic GABA(A) receptors are heteromeric structures composed of a combination of five from at least 16 different subunits. Subunit genes are expressed in distinct cell types at specific times during development. The most abundant native GABA(A) receptors consist of alpha1-, beta2-, and gamma2-subunits that are co-expressed in numerous brain areas. alpha3-, theta-, And epsilon-subunits are clustered on the X chromosome and show striking overlapping expression patterns throughout the adult rat brain. To establish whether these subunits are temporally and spatially co-expressed, we used in situ hybridization to analyze their expression throughout rat development from embryonic stage E14 to postnatal stage P12. Each transcript exhibited a unique or a shared regional and temporal developmental expression profile. The thalamic expression pattern evolved from a restricted expression of epsilon and theta transcripts before birth, to a theta and alpha3 expression at birth, and finally to a grouped epsilon, theta and alpha3 expression postpartum. However, strong similarities occurred, such as a grouped expression of the three subunits within the hypothalamus, tegmentum and pontine nuclei throughout the developmental process. At early stages of development (E17), epsilon and theta appeared to have a greater spatial distribution before the dominance of the alpha3 subunit transcript around birth. We also revealed expression of alpha3, theta, and epsilon in the developing spinal cord and identified neurons that express epsilon in the postnatal dorsal horn, intermediolateral column and motoneurons. Our findings suggest that various combinations of alpha3-, theta- and epsilon-subunits may be assembled at a regional and developmental level in the brain.
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Affiliation(s)
- J-R Pape
- Université de Bordeaux, CNRS, UMR 5228, France
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Kakinuma H, Sato H. Copy-number variations associated with autism spectrum disorder. Pharmacogenomics 2009; 9:1143-54. [PMID: 18681787 DOI: 10.2217/14622416.9.8.1143] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Autism spectrum disorder (ASD) is a clinically heterogeneous developmental disorder with a strong genetic component. Rare genetic disorders and various chromosomal abnormalities are thought to account for approximately 10% of people with ASD. The etiology of the remaining cases remains unknown. Recent advances in array-based technology have increased the resolution in detecting submicroscopic deletions and duplications, referred to as copy-number variations. ASD-associated copy-number variations, which are considered to be present in individuals with ASD but not in unaffected individuals, have been extensively investigated. These data will provide us with an opportunity not only to search for genes causing or contributing to ASDs but also to understand the genetics of ASD.
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Affiliation(s)
- Hiroaki Kakinuma
- Department of Pediatrics, Kanazawa Medical University, 1-1 Uchinada, Kahoku-gun, Ishikawa 920-293, Japan.
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Abstract
Angelman syndrome has been suggested as a disease model of neurogenetic developmental condition with a specific behavioral phenotype. It is due to lack of expression of the UBE3A gene, an imprinted gene located on chromosome 15q. Here we review the main features of this phenotype, characterized by happy demeanor with prominent smiling, poorly specific laughing and general exuberance, associated with hypermotor behavior, stereotypies, and reduced behavioral adaptive skills despite proactive social contact. All these phenotypic characteristics are currently difficult to quantify and have been subject to some differences in interpretation. For example, prevalence of autistic disorder is still debated. Many of these features may occur in other syndromic or nonsyndromic forms of severe intellectual disability, but their combination, with particularly prominent laughter and smiling may be specific of Angelman syndrome. Management of problematic behaviors is primarily based on behavioral approaches, though psychoactive medication (eg, neuroleptics or antidepressants) may be required.
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Affiliation(s)
- Karine Pelc
- Department of Neurology, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB)Brussels, Belgium
| | - Guy Cheron
- Laboratory of Neurophysiology and Movement Biomechanics, Université Libre de Bruxelles (ULB)Brussels, Belgium
| | - Bernard Dan
- Department of Neurology, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB)Brussels, Belgium
- Laboratory of Neurophysiology and Movement Biomechanics, Université Libre de Bruxelles (ULB)Brussels, Belgium
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