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Lozovaya N, Eftekhari S, Hammond C. The early excitatory action of striatal cholinergic-GABAergic microcircuits conditions the subsequent GABA inhibitory shift. Commun Biol 2023; 6:723. [PMID: 37452171 PMCID: PMC10349145 DOI: 10.1038/s42003-023-05068-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 06/23/2023] [Indexed: 07/18/2023] Open
Abstract
Cholinergic interneurons of the striatum play a role in action selection and associative learning by activating local GABAergic inhibitory microcircuits. We investigated whether cholinergic-GABAergic microcircuits function differently and fulfill a different role during early postnatal development, when GABAA actions are not inhibitory and mice pups do not walk. We focused our study mainly on dual cholinergic/GABAergic interneurons (CGINs). We report that morphological and intrinsic electrophysiological properties of CGINs rapidly develop during the first post-natal week. At this stage, CGINs are excited by the activation of GABAA receptors or GABAergic synaptic inputs, respond to cortical stimulation by a long excitation and are linked by polysynaptic excitations. All these excitations are replaced by inhibitions at P12-P15. Early chronic treatment with the NKCC1 antagonist bumetanide to evoke premature GABAergic inhibitions from P4 to P8, prevented the GABA polarity shift and corticostriatal pause response at control postnatal days. We propose that early excitatory cholinergic-GABAergic microcircuits are instrumental in the maturation of GABAergic inhibition.
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2
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Fernandez A, Dumon C, Guimond D, Tyzio R, Bonifazi P, Lozovaya N, Burnashev N, Ferrari DC, Ben-Ari Y. The GABA Developmental Shift Is Abolished by Maternal Immune Activation Already at Birth. Cereb Cortex 2020; 29:3982-3992. [PMID: 30395185 DOI: 10.1093/cercor/bhy279] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 09/14/2018] [Accepted: 10/11/2018] [Indexed: 01/27/2023] Open
Abstract
Epidemiological and experimental studies suggest that maternal immune activation (MIA) leads to developmental brain disorders, but whether the pathogenic mechanism impacts neurons already at birth is not known. We now report that MIA abolishes in mice the oxytocin-mediated delivery γ-aminobutyric acid (GABA) shift from depolarizing to hyperpolarizing in CA3 pyramidal neurons, and this is restored by the NKCC1 chloride importer antagonist bumetanide. Furthermore, MIA hippocampal pyramidal neurons at birth have a more exuberant apical arbor organization and increased apical dendritic length than age-matched controls. The frequency of spontaneous glutamatergic postsynaptic currents is also increased in MIA offspring, as well as the pairwise correlation of the synchronized firing of active cells in CA3. These alterations produced by MIA persist, since at P14-15 GABA action remains depolarizing, produces excitatory action, and network activity remains elevated with a higher frequency of spontaneous glutamatergic postsynaptic currents. Therefore, the pathogenic actions of MIA lead to important morphophysiological and network alterations in the hippocampus already at birth.
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Affiliation(s)
- Amandine Fernandez
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc Scientifique et Technologique de Luminy, MARSEILLE Cedex 09, France.,Mediterranean Institute of Neurobiology (INMED), INSERM UMR1249, Marseille, France.,Aix-Marseille University UMR 1249, Marseille, France
| | - Camille Dumon
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc Scientifique et Technologique de Luminy, MARSEILLE Cedex 09, France.,Aix-Marseille University UMR 1249, Marseille, France
| | - Damien Guimond
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc Scientifique et Technologique de Luminy, MARSEILLE Cedex 09, France
| | - Roman Tyzio
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc Scientifique et Technologique de Luminy, MARSEILLE Cedex 09, France.,Mediterranean Institute of Neurobiology (INMED), INSERM UMR1249, Marseille, France.,Aix-Marseille University UMR 1249, Marseille, France
| | - Paolo Bonifazi
- Biocruces Health Research Institute, Barakaldo, Spain.,IKERBASQUE: The Basque Foundation for Science, Bilbao, Spain
| | - Natalia Lozovaya
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc Scientifique et Technologique de Luminy, MARSEILLE Cedex 09, France
| | - Nail Burnashev
- Mediterranean Institute of Neurobiology (INMED), INSERM UMR1249, Marseille, France.,Aix-Marseille University UMR 1249, Marseille, France
| | - Diana C Ferrari
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc Scientifique et Technologique de Luminy, MARSEILLE Cedex 09, France
| | - Yehezkel Ben-Ari
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc Scientifique et Technologique de Luminy, MARSEILLE Cedex 09, France.,Mediterranean Institute of Neurobiology (INMED), INSERM UMR1249, Marseille, France
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3
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Pons-Bennaceur A, Tsintsadze V, Bui TT, Tsintsadze T, Minlebaev M, Milh M, Scavarda D, Giniatullin R, Giniatullina R, Shityakov S, Wright M, Miller AD, Lozovaya N, Burnashev N. Diadenosine-Polyphosphate Analogue AppCH2ppA Suppresses Seizures by Enhancing Adenosine Signaling in the Cortex. Cereb Cortex 2020; 29:3778-3795. [PMID: 30295710 DOI: 10.1093/cercor/bhy257] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 08/15/2018] [Accepted: 09/14/2018] [Indexed: 01/16/2023] Open
Abstract
Epilepsy is a multifactorial disorder associated with neuronal hyperexcitability that affects more than 1% of the human population. It has long been known that adenosine can reduce seizure generation in animal models of epilepsies. However, in addition to various side effects, the instability of adenosine has precluded its use as an anticonvulsant treatment. Here we report that a stable analogue of diadenosine-tetraphosphate: AppCH2ppA effectively suppresses spontaneous epileptiform activity in vitro and in vivo in a Tuberous Sclerosis Complex (TSC) mouse model (Tsc1+/-), and in postsurgery cortical samples from TSC human patients. These effects are mediated by enhanced adenosine signaling in the cortex post local neuronal adenosine release. The released adenosine induces A1 receptor-dependent activation of potassium channels thereby reducing neuronal excitability, temporal summation, and hypersynchronicity. AppCH2ppA does not cause any disturbances of the main vital autonomous functions of Tsc1+/- mice in vivo. Therefore, we propose this compound to be a potent new candidate for adenosine-related treatment strategies to suppress intractable epilepsies.
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Affiliation(s)
- Alexandre Pons-Bennaceur
- INSERM UMR1249, Mediterranean Institute of Neurobiology (INMED), Aix-Marseille University, Parc Scientifique de Luminy, Marseille, France
| | - Vera Tsintsadze
- INSERM UMR1249, Mediterranean Institute of Neurobiology (INMED), Aix-Marseille University, Parc Scientifique de Luminy, Marseille, France.,Knight Cardiovascular Institute, Oregon Health and Science University, OR, USA
| | - Thi-Thien Bui
- B&A Therapeutics, Ben-Ari Institute of Neuroarcheology, Batiment Beret-Delaage, Zone Luminy Biotech Entreprises, Marseille, Cedex 09, France
| | - Timur Tsintsadze
- INSERM UMR1249, Mediterranean Institute of Neurobiology (INMED), Aix-Marseille University, Parc Scientifique de Luminy, Marseille, France
| | - Marat Minlebaev
- INSERM UMR1249, Mediterranean Institute of Neurobiology (INMED), Aix-Marseille University, Parc Scientifique de Luminy, Marseille, France.,Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
| | - Mathieu Milh
- APHM, Department of Pediatric Neurosurgery and Neurology, CHU Timone, Marseille Cedex 5, France
| | - Didier Scavarda
- APHM, Department of Pediatric Neurosurgery and Neurology, CHU Timone, Marseille Cedex 5, France
| | - Rashid Giniatullin
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,A.I. Virtanen Institute for Molecular Sciences, Department of Neurobiology, University of Eastern Finland, Kuopio, Finland
| | - Raisa Giniatullina
- A.I. Virtanen Institute for Molecular Sciences, Department of Neurobiology, University of Eastern Finland, Kuopio, Finland
| | - Sergey Shityakov
- Department of Anaesthesia and Critical Care, University of Würzburg, Josef-Schneider-Street 2, Würzburg, Germany
| | - Michael Wright
- School of Cancer and Pharmaceutical Sciences, King's College London, Franklin-Wilkins Building, Waterloo Campus, 150 Stamford Street, London, UK
| | - Andrew D Miller
- School of Cancer and Pharmaceutical Sciences, King's College London, Franklin-Wilkins Building, Waterloo Campus, 150 Stamford Street, London, UK.,Veterinary Research Institute, Hudcova 296/70, Brno, Czech Republic.,KP Therapeutics Ltd, 86 Deansgate, Manchester, UK
| | - Natalia Lozovaya
- B&A Therapeutics, Ben-Ari Institute of Neuroarcheology, Batiment Beret-Delaage, Zone Luminy Biotech Entreprises, Marseille, Cedex 09, France
| | - Nail Burnashev
- INSERM UMR1249, Mediterranean Institute of Neurobiology (INMED), Aix-Marseille University, Parc Scientifique de Luminy, Marseille, France
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4
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Lozovaya N, Nardou R, Tyzio R, Chiesa M, Pons-Bennaceur A, Eftekhari S, Bui TT, Billon-Grand M, Rasero J, Bonifazi P, Guimond D, Gaiarsa JL, Ferrari DC, Ben-Ari Y. Early alterations in a mouse model of Rett syndrome: the GABA developmental shift is abolished at birth. Sci Rep 2019; 9:9276. [PMID: 31239460 PMCID: PMC6592949 DOI: 10.1038/s41598-019-45635-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 06/11/2019] [Indexed: 02/06/2023] Open
Abstract
Genetic mutations of the Methyl-CpG-binding protein-2 (MECP2) gene underlie Rett syndrome (RTT). Developmental processes are often considered to be irrelevant in RTT pathogenesis but neuronal activity at birth has not been recorded. We report that the GABA developmental shift at birth is abolished in CA3 pyramidal neurons of Mecp2-/y mice and the glutamatergic/GABAergic postsynaptic currents (PSCs) ratio is increased. Two weeks later, GABA exerts strong excitatory actions, the glutamatergic/GABAergic PSCs ratio is enhanced, hyper-synchronized activity is present and metabotropic long-term depression (LTD) is impacted. One day before delivery, maternal administration of the NKCC1 chloride importer antagonist bumetanide restored these parameters but not respiratory or weight deficits, nor the onset of mortality. Results suggest that birth is a critical period in RTT with important alterations that can be attenuated by bumetanide raising the possibility of early treatment of the disorder.
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Affiliation(s)
- N Lozovaya
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288, Marseille, cedex 09, France
| | - R Nardou
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288, Marseille, cedex 09, France
| | - R Tyzio
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288, Marseille, cedex 09, France.,Mediterranean Institute of Neurobiology (INMED), Department of Neurobiology, Aix-Marseille University, INSERM U1249, 13273, Marseille, France
| | - M Chiesa
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288, Marseille, cedex 09, France.,Mediterranean Institute of Neurobiology (INMED), Department of Neurobiology, Aix-Marseille University, INSERM U1249, 13273, Marseille, France
| | - A Pons-Bennaceur
- Mediterranean Institute of Neurobiology (INMED), Department of Neurobiology, Aix-Marseille University, INSERM U1249, 13273, Marseille, France
| | - S Eftekhari
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288, Marseille, cedex 09, France.,Mediterranean Institute of Neurobiology (INMED), Department of Neurobiology, Aix-Marseille University, INSERM U1249, 13273, Marseille, France
| | - T-T Bui
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288, Marseille, cedex 09, France.,Mediterranean Institute of Neurobiology (INMED), Department of Neurobiology, Aix-Marseille University, INSERM U1249, 13273, Marseille, France
| | - M Billon-Grand
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288, Marseille, cedex 09, France
| | - J Rasero
- Biocruces Health Research Institute, 48903, Barakaldo, Spain
| | - P Bonifazi
- Biocruces Health Research Institute, 48903, Barakaldo, Spain.,IKERBASQUE: The Basque Foundation for Science, 48013, Bilbao, Spain
| | - D Guimond
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288, Marseille, cedex 09, France
| | - J-L Gaiarsa
- Mediterranean Institute of Neurobiology (INMED), Department of Neurobiology, Aix-Marseille University, INSERM U1249, 13273, Marseille, France
| | - D C Ferrari
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288, Marseille, cedex 09, France
| | - Y Ben-Ari
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288, Marseille, cedex 09, France.
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5
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Cloarec R, Riffault B, Dufour A, Rabiei H, Gouty-Colomer LA, Dumon C, Guimond D, Bonifazi P, Eftekhari S, Lozovaya N, Ferrari DC, Ben-Ari Y. Pyramidal neuron growth and increased hippocampal volume during labor and birth in autism. Sci Adv 2019; 5:eaav0394. [PMID: 30746473 PMCID: PMC6357736 DOI: 10.1126/sciadv.aav0394] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 12/10/2018] [Indexed: 06/09/2023]
Abstract
We report that the apical dendrites of CA3 hippocampal pyramidal neurons are increased during labor and birth in the valproate model of autism but not in control animals. Using the iDISCO clearing method, we show that hippocampal, especially CA3 region, and neocortical volumes are increased and that the cerebral volume distribution shifts from normal to lognormal in valproate-treated animals. Maternal administration during labor and birth of the NKCC1 chloride transporter antagonist bumetanide, which reduces [Cl-]i levels and attenuates the severity of autism, abolished the neocortical and hippocampal volume changes and reduced the whole-brain volume in valproate-treated animals. These results suggest that the abolition of the oxytocin-mediated excitatory-to-inhibitory shift of GABA actions during labor and birth contributes to the pathogenesis of autism spectrum disorders by stimulating growth during a vulnerable period.
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Affiliation(s)
- R. Cloarec
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Zone Luminy Biotech Entreprises, 13288 Cedex 09 , Marseille, France
| | - B. Riffault
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Zone Luminy Biotech Entreprises, 13288 Cedex 09 , Marseille, France
| | - A. Dufour
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Zone Luminy Biotech Entreprises, 13288 Cedex 09 , Marseille, France
| | - H. Rabiei
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Zone Luminy Biotech Entreprises, 13288 Cedex 09 , Marseille, France
| | - L.-A. Gouty-Colomer
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Zone Luminy Biotech Entreprises, 13288 Cedex 09 , Marseille, France
| | - C. Dumon
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Zone Luminy Biotech Entreprises, 13288 Cedex 09 , Marseille, France
| | - D. Guimond
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Zone Luminy Biotech Entreprises, 13288 Cedex 09 , Marseille, France
| | - P. Bonifazi
- Biocruces Health Research Institute, Barakaldo, Spain & IKERBASQUE: The Basque Foundation for Science, Bilbao, Spain
| | - S. Eftekhari
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Zone Luminy Biotech Entreprises, 13288 Cedex 09 , Marseille, France
| | - N. Lozovaya
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Zone Luminy Biotech Entreprises, 13288 Cedex 09 , Marseille, France
| | - D. C. Ferrari
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Zone Luminy Biotech Entreprises, 13288 Cedex 09 , Marseille, France
| | - Y. Ben-Ari
- Neurochlore, Ben-Ari Institute of Neuroarcheology (IBEN), Zone Luminy Biotech Entreprises, 13288 Cedex 09 , Marseille, France
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6
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Abstract
The rule of one terminal and one transmitter acting on one synapse clearly fails to cover the complexity of chemical synapse operation in the brain. Compelling evidence now indicates that two transmitters can be released from the same terminal, acting in a complementary manner to generate complex electrical activity in the targets. Our laboratory now showed that a subpopulation striatal cholinergic neurons also release the classical inhibitory transmitter GABA with a balance between excitation and inhibition being provided by acetylcholine and GABA, respectively. An illustration of the importance of this dual release comes from the fact that when dopamine signals are absent such as in Parkinson disease (PD) the GABAergic inhibition in these dual cholinergic/GABAergic cells fails because of high intracellular chloride ((Cl-)I) levels rendering the cholinergic excitatory component unmet by a parallel inhibitory drive. Restoring low (Cl-)I with the NKCC1 chloride importer antagonist bumetanide attenuates the electrical and motor disturbance. In addition to illustrating the complex interactions between two transmitters acting at the same synapse, this study paves the way to novel conceptual treatment of PD based on restoration of GABAergic inhibition in keeping with our pilot clinical trial showing indeed that bumetanide together with levodopa attenuates axial motor disturbance. It is also in keeping with extensive investigations showing increased (Cl-)I levels and weakened inhibition in a wide range of pathological insults and their restoration by bumetanide. It raises fundamental issues related to the operation of the striatum and basal ganglia in health and disease.
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Affiliation(s)
- Natalia Lozovaya
- Neurochlore and B&A Therapeutics, Ben-Ari Institute of Neuroarcheology, Batiment Beret-Delaage, zone Luminy entreprises, 13288 Marseille, Cedex 09, France
| | - Yehezkel Ben-Ari
- Neurochlore and B&A Therapeutics, Ben-Ari Institute of Neuroarcheology, Batiment Beret-Delaage, zone Luminy entreprises, 13288 Marseille, Cedex 09, France
| | - Constance Hammond
- Neurochlore and B&A Therapeutics, Ben-Ari Institute of Neuroarcheology, Batiment Beret-Delaage, zone Luminy entreprises, 13288 Marseille, Cedex 09, France
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7
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Chiesa M, Guimond D, Tyzio R, Pons-Bennaceur A, Lozovaya N, Burnashev N, Ferrari DC, Ben-Ari Y. Term or Preterm Cesarean Section Delivery Does Not Lead to Long-term Detrimental Consequences in Mice. Cereb Cortex 2018; 29:2424-2436. [DOI: 10.1093/cercor/bhy112] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 04/19/2018] [Indexed: 12/26/2022] Open
Affiliation(s)
- Morgane Chiesa
- Neurochlore, Fundamental Research Department, bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288 Marseille cedex, France
- Mediterranean Institute of Neurobiology (INMED), Department of Neurobiology, Aix-Marseille University, INSERM U1249, Marseille, France
| | - Damien Guimond
- Neurochlore, Fundamental Research Department, bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288 Marseille cedex, France
| | - Roman Tyzio
- Neurochlore, Fundamental Research Department, bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288 Marseille cedex, France
- Mediterranean Institute of Neurobiology (INMED), Department of Neurobiology, Aix-Marseille University, INSERM U1249, Marseille, France
| | - Alexandre Pons-Bennaceur
- Mediterranean Institute of Neurobiology (INMED), Department of Neurobiology, Aix-Marseille University, INSERM U1249, Marseille, France
| | - Natalia Lozovaya
- Neurochlore, Fundamental Research Department, bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288 Marseille cedex, France
| | - Nail Burnashev
- Mediterranean Institute of Neurobiology (INMED), Department of Neurobiology, Aix-Marseille University, INSERM U1249, Marseille, France
| | - Diana C Ferrari
- Neurochlore, Fundamental Research Department, bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288 Marseille cedex, France
| | - Yehezkel Ben-Ari
- Neurochlore, Fundamental Research Department, bâtiment Beret-Delaage, Parc scientifique et technologique de Luminy, 13288 Marseille cedex, France
- Mediterranean Institute of Neurobiology (INMED), Department of Neurobiology, Aix-Marseille University, INSERM U1249, Marseille, France
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8
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Abstract
Analysis of electrophysiological properties of NMDARs and NMDAR-mediated synaptic transmission in identified neurons and synapses in brain slices is a major step in understanding their function in normal and pathological neuronal brain networks. In many central synapses excitatory postsynaptic currents (EPSCs) are mediated by excitatory neurotransmitter glutamate that activates colocalized AMPAR and NMDAR generating a complex EPSC. Here, we describe the methods commonly used in brain slices to study the electrophysiological properties of NMDAR-mediated component of spontaneous or evoked EPSCs by extracellular stimulation or by stimulating synaptically connected neurons. This approach is based on whole-cell patch-clamp recordings, pharmacological tools, and the analysis of the difference in temporal parameters between the AMPA and NMDA receptors. It allows pinpointing of the basic functional properties of NMDARs that are specific to identified brain regions, neurons, and synapses of wild-type or genetically manipulated mice.
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Affiliation(s)
- Alexandre Pons-Bennaceur
- INSERM U901, Mediterranean Institute of Neurobiology (INMED), Aix-Marseille University, Marseille, France
| | - Natalia Lozovaya
- Neurochlore c/o Mediterranean Institute of Neurobiology (INMED), INSERM U901, Parc Scientifique de Luminy, BP13, 13273, Marseille Cedex 09, France.
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9
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Viatchenko-Karpinski V, Novosolova N, Ishchenko Y, Azhar MA, Wright M, Tsintsadze V, Kamal A, Burnashev N, Miller AD, Voitenko N, Giniatullin R, Lozovaya N. Stable, synthetic analogs of diadenosine tetraphosphate inhibit rat and human P2X3 receptors and inflammatory pain. Mol Pain 2016; 12:1744806916637704. [PMID: 27030723 PMCID: PMC4955970 DOI: 10.1177/1744806916637704] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Accepted: 12/08/2015] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND A growing body of evidence suggests that ATP-gated P2X3 receptors (P2X3Rs) are implicated in chronic pain. We address the possibility that stable, synthetic analogs of diadenosine tetraphosphate (Ap4A) might induce antinociceptive effects by inhibiting P2X3Rs in peripheral sensory neurons. RESULTS The effects of two stable, synthetic Ap4A analogs (AppNHppA and AppCH2ppA) are studied firstly in vitro on HEK293 cells expressing recombinant rat P2XRs (P2X2Rs, P2X3Rs, P2X4Rs, and P2X7Rs) and then using native rat brain cells (cultured trigeminal, nodose, or dorsal root ganglion neurons). Thereafter, the action of these stable, synthetic Ap4A analogs on inflammatory pain and thermal hyperalgesia is studied through the measurement of antinociceptive effects in formalin and Hargreaves plantar tests in rats in vivo. In vitro inhibition of rat P2X3Rs (not P2X2Rs, P2X4Rs nor P2X7Rs) is shown to take place mediated by high-affinity desensitization (at low concentrations; IC50 values 100-250 nM) giving way to only weak partial agonism at much higher concentrations (EC50 values ≥ 10 µM). Similar inhibitory activity is observed with human recombinant P2X3Rs. The inhibitory effects of AppNHppA on nodose, dorsal root, and trigeminal neuron whole cell currents suggest that stable, synthetic Ap4A analogs inhibit homomeric P2X3Rs in preference to heteromeric P2X2/3Rs. Both Ap4A analogs mediate clear inhibition of pain responses in both in vivo inflammation models. CONCLUSIONS Stable, synthetic Ap4A analogs (AppNHppA and AppCH2ppA) being weak partial agonist provoke potent high-affinity desensitization-mediated inhibition of homomeric P2X3Rs at low concentrations. Therefore, both analogs demonstrate clear potential as potent analgesic agents for use in the management of chronic pain associated with heightened P2X3R activation.
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Affiliation(s)
- Viacheslav Viatchenko-Karpinski
- Laboratory of Sensory Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine International Center for Molecular Physiology, Kiev, Ukraine
| | | | | | - M Ameruddin Azhar
- Indian Institute of Chemical Technology, Hyderabad, India Imperial College Genetic Therapies Centre, Department of Chemistry, Imperial College London, London, UK
| | - Michael Wright
- Imperial College Genetic Therapies Centre, Department of Chemistry, Imperial College London, London, UK Institute of Pharmaceutical Science, King's College London, London, UK
| | - Vera Tsintsadze
- INSERM UMR901 Aix-Marseille Université, Marseille, France INMED, Institut de Neurobiologie de la Méditerranée, Marseille, France
| | - Ahmed Kamal
- Indian Institute of Chemical Technology, Hyderabad, India
| | - Nail Burnashev
- INSERM UMR901 Aix-Marseille Université, Marseille, France INMED, Institut de Neurobiologie de la Méditerranée, Marseille, France
| | - Andrew D Miller
- Institute of Pharmaceutical Science, King's College London, London, UK GlobalAcorn Ltd, London, UK
| | - Nana Voitenko
- Laboratory of Sensory Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine International Center for Molecular Physiology, Kiev, Ukraine
| | - Rashid Giniatullin
- Department of Neurobiology, A. I. Virtanen Institute, Kuopio, Finland Kazan Federal University, Kazan, Russia
| | - Natalia Lozovaya
- INSERM UMR901 Aix-Marseille Université, Marseille, France INMED, Institut de Neurobiologie de la Méditerranée, Marseille, France Neurochlore, Marseille, France
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10
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Lozovaya N, Gataullina S, Tsintsadze T, Tsintsadze V, Pallesi-Pocachard E, Minlebaev M, Goriounova NA, Buhler E, Watrin F, Shityakov S, Becker AJ, Bordey A, Milh M, Scavarda D, Bulteau C, Dorfmuller G, Delalande O, Represa A, Cardoso C, Dulac O, Ben-Ari Y, Burnashev N. Selective suppression of excessive GluN2C expression rescues early epilepsy in a tuberous sclerosis murine model. Nat Commun 2014; 5:4563. [PMID: 25081057 PMCID: PMC4143949 DOI: 10.1038/ncomms5563] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 06/30/2014] [Indexed: 01/06/2023] Open
Abstract
Tuberous sclerosis complex (TSC), caused by dominant mutations in either
TSC1 or
TSC2 tumour
suppressor genes is characterized by the presence of brain malformations, the
cortical tubers that are thought to contribute to the generation of
pharmacoresistant epilepsy. Here we report that tuberless heterozygote
Tsc1+/− mice show
functional upregulation of cortical GluN2C-containing N-methyl-D-aspartate receptors (NMDARs) in an
mTOR-dependent manner and exhibit recurrent, unprovoked seizures during early
postnatal life (<P19). Seizures are generated intracortically in the granular
layer of the neocortex. Slow kinetics of aberrant GluN2C-mediated currents in spiny stellate cells promotes
excessive temporal integration of persistent NMDAR-mediated recurrent excitation and
seizure generation. Accordingly, specific GluN2C/D antagonists block seizures in Tsc1+/− mice in vivo
and in vitro. Likewise, GluN2C expression is upregulated in TSC human surgical
resections, and a GluN2C/D
antagonist reduces paroxysmal hyperexcitability. Thus, GluN2C receptor constitutes a promising
molecular target to treat epilepsy in TSC patients. Tuberous sclerosis complex (TSC) is a rare genetic condition
characterized by epileptic seizures that start in infancy. Here, the authors show that
these seizures are modulated by GluN2C-containing NMDA receptors in the cortex of a
mouse model of TSC, and that suppressing their activity attenuates seizures.
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Affiliation(s)
- N Lozovaya
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France [3] INSERM U1129; University Paris Descartes, CEA, Gif sur Yvette, 149 Rue de Sèvres, 75015 Paris, France [4]
| | - S Gataullina
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France [3] INSERM U1129; University Paris Descartes, CEA, Gif sur Yvette, 149 Rue de Sèvres, 75015 Paris, France [4]
| | - T Tsintsadze
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France [3]
| | - V Tsintsadze
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France
| | - E Pallesi-Pocachard
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France
| | - M Minlebaev
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France [3] Laboratory of Neurobiology, Kazan Federal University, Kremlevskaya street 18, 420000 Kazan, Russia
| | - N A Goriounova
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France
| | - E Buhler
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France
| | - F Watrin
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France
| | - S Shityakov
- Department of Anaesthesia and Critical Care, University of Würzburg, Josef-Schneider-Street 2, 97080 Würzburg, Germany
| | - A J Becker
- Department of Neuropathology, University of Bonn Medical Center, Sigmund Freud Street 25, D-53105 Bonn, Germany
| | - A Bordey
- Neurosurgery, and Cellular and Molecular Physiology Departments, Yale University School of Medicine, PO Box 208082, New Haven, Connecticut 06520-8082, USA
| | - M Milh
- APHM, Department of Pediatric Neurosurgery and Neurology, CHU Timone, 264 Rue Saint-Pierre, 13385 Marseille Cedex 5, France
| | - D Scavarda
- APHM, Department of Pediatric Neurosurgery and Neurology, CHU Timone, 264 Rue Saint-Pierre, 13385 Marseille Cedex 5, France
| | - C Bulteau
- 1] INSERM U1129; University Paris Descartes, CEA, Gif sur Yvette, 149 Rue de Sèvres, 75015 Paris, France [2] Department of Pediatric Neurosurgery, Foundation Rothschild, 29 Rue Manin, 75019 Paris, France
| | - G Dorfmuller
- 1] INSERM U1129; University Paris Descartes, CEA, Gif sur Yvette, 149 Rue de Sèvres, 75015 Paris, France [2] Department of Pediatric Neurosurgery, Foundation Rothschild, 29 Rue Manin, 75019 Paris, France
| | - O Delalande
- Department of Pediatric Neurosurgery, Foundation Rothschild, 29 Rue Manin, 75019 Paris, France
| | - A Represa
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France
| | - C Cardoso
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France
| | - O Dulac
- 1] INSERM U1129; University Paris Descartes, CEA, Gif sur Yvette, 149 Rue de Sèvres, 75015 Paris, France [2] Department of Pediatric Neurosurgery, Foundation Rothschild, 29 Rue Manin, 75019 Paris, France [3] APHP, Necker Hospital, 149 Rue de Sèvres, 75015 Paris, France
| | - Y Ben-Ari
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France
| | - N Burnashev
- 1] INSERM U901, INMED, Parc Scientifique et Technologique de Luminy 163, route de Luminy-BP 13, 13273 Marseille Cedex 09, France [2] UMR901, Aix-Marseille University, 58 Boulevard Charles Livon, 13284 Marseille, France
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11
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Golovko T, Min R, Lozovaya N, Falconer C, Yatsenko N, Tsintsadze T, Tsintsadze V, Ledent C, Harvey RJ, Belelli D, Lambert JJ, Rozov A, Burnashev N. Control of Inhibition by the Direct Action of Cannabinoids on GABAAReceptors. Cereb Cortex 2014; 25:2440-55. [DOI: 10.1093/cercor/bhu045] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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12
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Tyzio R, Nardou R, Ferrari DC, Tsintsadze T, Shahrokhi A, Eftekhari S, Khalilov I, Tsintsadze V, Brouchoud C, Chazal G, Lemonnier E, Lozovaya N, Burnashev N, Ben-Ari Y. Oxytocin-mediated GABA inhibition during delivery attenuates autism pathogenesis in rodent offspring. Science 2014; 343:675-9. [PMID: 24503856 DOI: 10.1126/science.1247190] [Citation(s) in RCA: 412] [Impact Index Per Article: 41.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We report that the oxytocin-mediated neuroprotective γ-aminobutyric acid (GABA) excitatory-inhibitory shift during delivery is abolished in the valproate and fragile X rodent models of autism. During delivery and subsequently, hippocampal neurons in these models have elevated intracellular chloride levels, increased excitatory GABA, enhanced glutamatergic activity, and elevated gamma oscillations. Maternal pretreatment with bumetanide restored in offspring control electrophysiological and behavioral phenotypes. Conversely, blocking oxytocin signaling in naïve mothers produced offspring having electrophysiological and behavioral autistic-like features. Our results suggest a chronic deficient chloride regulation in these rodent models of autism and stress the importance of oxytocin-mediated GABAergic inhibition during the delivery process. Our data validate the amelioration observed with bumetanide and oxytocin and point to common pathways in a drug-induced and a genetic rodent model of autism.
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Affiliation(s)
- Roman Tyzio
- Mediterranean Institute of Neurobiology (INMED), U901, INSERM, Marseille, France
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13
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Lesca G, Rudolf G, Bruneau N, Lozovaya N, Labalme A, Boutry-Kryza N, Salmi M, Tsintsadze T, Addis L, Motte J, Wright S, Tsintsadze V, Michel A, Doummar D, Lascelles K, Strug L, Waters P, de Bellescize J, Vrielynck P, de Saint Martin A, Ville D, Ryvlin P, Arzimanoglou A, Hirsch E, Vincent A, Pal D, Burnashev N, Sanlaville D, Szepetowski P. GRIN2A mutations in acquired epileptic aphasia and related childhood focal epilepsies and encephalopathies with speech and language dysfunction. Nat Genet 2013; 45:1061-6. [PMID: 23933820 DOI: 10.1038/ng.2726] [Citation(s) in RCA: 296] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 07/18/2013] [Indexed: 12/20/2022]
Abstract
Epileptic encephalopathies are severe brain disorders with the epileptic component contributing to the worsening of cognitive and behavioral manifestations. Acquired epileptic aphasia (Landau-Kleffner syndrome, LKS) and continuous spike and waves during slow-wave sleep syndrome (CSWSS) represent rare and closely related childhood focal epileptic encephalopathies of unknown etiology. They show electroclinical overlap with rolandic epilepsy (the most frequent childhood focal epilepsy) and can be viewed as different clinical expressions of a single pathological entity situated at the crossroads of epileptic, speech, language, cognitive and behavioral disorders. Here we demonstrate that about 20% of cases of LKS, CSWSS and electroclinically atypical rolandic epilepsy often associated with speech impairment can have a genetic origin sustained by de novo or inherited mutations in the GRIN2A gene (encoding the N-methyl-D-aspartate (NMDA) glutamate receptor α2 subunit, GluN2A). The identification of GRIN2A as a major gene for these epileptic encephalopathies provides crucial insights into the underlying pathophysiology.
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Affiliation(s)
- Gaetan Lesca
- Department of Genetics, University Hospitals of Lyon, Lyon, France
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14
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Salmi M, Bruneau N, Cillario J, Lozovaya N, Massacrier A, Buhler E, Cloarec R, Tsintsadze T, Watrin F, Tsintsadze V, Zimmer C, Villard C, Lafitte D, Cardoso C, Bao L, Lesca G, Rudolf G, Muscatelli F, Pauly V, Khalilov I, Durbec P, Ben-Ari Y, Burnashev N, Represa A, Szepetowski P. Tubacin prevents neuronal migration defects and epileptic activity caused by rat Srpx2 silencing in utero. ACTA ACUST UNITED AC 2013; 136:2457-73. [PMID: 23831613 DOI: 10.1093/brain/awt161] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Altered development of the human cerebral cortex can cause severe malformations with often intractable focal epileptic seizures and may participate in common pathologies, notably epilepsy. This raises important conceptual and therapeutic issues. Two missense mutations in the sushi repeat-containing protein SRPX2 had been previously identified in epileptic disorders with or without structural developmental alteration of the speech cortex. In the present study, we aimed to decipher the precise developmental role of SRPX2, to have a better knowledge on the consequences of its mutations, and to start addressing therapeutic issues through the design of an appropriate animal model. Using an in utero Srpx2 silencing approach, we show that SRPX2 influences neuronal migration in the developing rat cerebral cortex. Wild-type, but not the mutant human SRPX2 proteins, rescued the neuronal migration phenotype caused by Srpx2 silencing in utero, and increased alpha-tubulin acetylation. Following in utero Srpx2 silencing, spontaneous epileptiform activity was recorded post-natally. The neuronal migration defects and the post-natal epileptic consequences were prevented early in embryos by maternal administration of tubulin deacetylase inhibitor tubacin. Hence epileptiform manifestations of developmental origin could be prevented in utero, using a transient and drug-based therapeutic protocol.
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Affiliation(s)
- Manal Salmi
- INSERM UMR_S901, Parc Scientifique de Luminy, 13273 Marseille, France
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15
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Lozovaya N, Mukhtarov M, Tsintsadze T, Ledent C, Burnashev N, Bregestovski P. Frequency-Dependent Cannabinoid Receptor-Independent Modulation of Glycine Receptors by Endocannabinoid 2-AG. Front Mol Neurosci 2011; 4:13. [PMID: 21847369 PMCID: PMC3147161 DOI: 10.3389/fnmol.2011.00013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Accepted: 07/13/2011] [Indexed: 02/02/2023] Open
Abstract
Endocannabinoids are known as retrograde messengers, being released from the postsynaptic neuron and acting on specific presynaptic G-protein-coupled cannabinoid (CB) receptors to decrease neurotransmitter release. Also, at physiologically relevant concentrations cannabinoids can directly modulate the function of voltage-gated and receptor-operated ion channels. Using patch-clamp recording we analyzed the consequences of the direct action of an endocannabinoid, 2-arachidonoylglycerol (2-AG), on the functional properties of glycine receptor channels (GlyRs) and ionic currents in glycinergic synapses. At physiologically relevant concentrations (0.1–1 μM), 2-AG directly affected the functions of recombinant homomeric α1H GlyR: it inhibited peak amplitude and dramatically enhanced desensitization. The action of 2-AG on GlyR-mediated currents developed rapidly, within ∼300 ms. Addition of 1 μM 2-AG strongly facilitated the depression of glycine-induced currents during repetitive (4–10 Hz) application of short (2 ms duration) pulses of glycine to outside-out patches. In brainstem slices from CB1 receptor knockout mice, 2-AG significantly decreased the extent of facilitation of synaptic currents in hypoglossal motoneurons during repetitive (10–20 Hz) stimulation. These observations suggest that endocannabinoids can modulate postsynaptic metaplasticity of glycinergic synaptic currents in a CB1 receptor-independent manner.
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Affiliation(s)
- Natalia Lozovaya
- INSERM U901, Institut de Neurobiologie de la Méditerranée Marseille, France
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16
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Groffen AJ, Martens S, Arazola RD, Cornelisse LN, Lozovaya N, de Jong APH, Goriounova NA, Habets RLP, Takai Y, Borst JG, Brose N, McMahon HT, Verhage M. Doc2b is a high-affinity Ca2+ sensor for spontaneous neurotransmitter release. Science 2010; 327:1614-8. [PMID: 20150444 PMCID: PMC2846320 DOI: 10.1126/science.1183765] [Citation(s) in RCA: 238] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Synaptic vesicle fusion in brain synapses occurs in phases that are either tightly coupled to action potentials (synchronous), immediately following action potentials (asynchronous), or as stochastic events in the absence of action potentials (spontaneous). Synaptotagmin-1, -2, and -9 are vesicle-associated Ca2+ sensors for synchronous release. Here we found that double C2 domain (Doc2) proteins act as Ca2+ sensors to trigger spontaneous release. Although Doc2 proteins are cytosolic, they function analogously to synaptotagmin-1 but with a higher Ca2+ sensitivity. Doc2 proteins bound to N-ethylmaleimide-sensitive factor attachment receptor (SNARE) complexes in competition with synaptotagmin-1. Thus, different classes of multiple C2 domain-containing molecules trigger synchronous versus spontaneous fusion, which suggests a general mechanism for synaptic vesicle fusion triggered by the combined actions of SNAREs and multiple C2 domain-containing proteins.
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Affiliation(s)
- Alexander J. Groffen
- Department of Functional Genomics, CNCR, Neuroscience Campus Amsterdam, VU University and VU Medical Center, Amsterdam, The Netherlands
| | - Sascha Martens
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge, UK
| | - Rocío Díez Arazola
- Department of Functional Genomics, CNCR, Neuroscience Campus Amsterdam, VU University and VU Medical Center, Amsterdam, The Netherlands
| | - L. Niels Cornelisse
- Department of Functional Genomics, CNCR, Neuroscience Campus Amsterdam, VU University and VU Medical Center, Amsterdam, The Netherlands
| | - Natalia Lozovaya
- Department of Functional Genomics, CNCR, Neuroscience Campus Amsterdam, VU University and VU Medical Center, Amsterdam, The Netherlands
- Department of Integrative Neurophysiology, CNCR, VU University, Amsterdam, The Netherlands
| | - Arthur P. H. de Jong
- Department of Functional Genomics, CNCR, Neuroscience Campus Amsterdam, VU University and VU Medical Center, Amsterdam, The Netherlands
| | - Natalia A. Goriounova
- Department of Functional Genomics, CNCR, Neuroscience Campus Amsterdam, VU University and VU Medical Center, Amsterdam, The Netherlands
- Department of Integrative Neurophysiology, CNCR, VU University, Amsterdam, The Netherlands
| | - Ron L. P. Habets
- Department of Neuroscience, Erasmus MC, University Medical Center Rotterdam, The Netherlands
| | - Yoshimi Takai
- Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Japan
| | - J. Gerard Borst
- Department of Neuroscience, Erasmus MC, University Medical Center Rotterdam, The Netherlands
| | - Nils Brose
- Max-Planck-Institut für Experimentelle Medizin, Abteilung Molekulare Neurobiologie, Göttingen, Germany
| | | | - Matthijs Verhage
- Department of Functional Genomics, CNCR, Neuroscience Campus Amsterdam, VU University and VU Medical Center, Amsterdam, The Netherlands
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17
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Lozovaya N, Min R, Tsintsadze V, Burnashev N. Dual modulation of CNS voltage-gated calcium channels by cannabinoids: Focus on CB1 receptor-independent effects. Cell Calcium 2009; 46:154-62. [PMID: 19682741 DOI: 10.1016/j.ceca.2009.07.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Accepted: 07/18/2009] [Indexed: 01/13/2023]
Abstract
The neuromodulatory effects of cannabinoids in the central nervous system have mainly been associated with G-protein coupled cannabinoid receptor (CB1R) mediated inhibition of voltage-gated calcium channels (VGCCs). Numerous studies show, however, that cannabinoids can also modulate VGCCs independent of CB1R activation. Nevertheless, despite the fact that endocannabinoids have a nearly equal efficacy for direct and CB1R-mediated effects on VGCC, the role of the direct cannabinoid-VGCC interaction has been largely underestimated. In this review, we summarize recent studies on the modulation of different types of VGCCs by cannabinoids, highlight the evidence for and implications of the CB1R-independent modulation, and put forward the concept, that direct interaction of cannabinoids and VGCCs is as important in regulation of VGCCs function as the CB1R-mediated effects.
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Affiliation(s)
- Natalia Lozovaya
- Institut de Neurobiologie de la Méditerranée INSERM U, Marseille, France
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18
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Krishtal O, Lozovaya N, Fedorenko A, Savelyev I, Chizhmakov I. The agonists for nociceptors are ubiquitous, but the modulators are specific: P2X receptors in the sensory neurons are modulated by cannabinoids. Pflugers Arch 2006; 453:353-60. [PMID: 16741755 DOI: 10.1007/s00424-006-0094-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2006] [Accepted: 04/18/2006] [Indexed: 10/24/2022]
Abstract
P2X2 and P2X3 receptors expressed in mammalian sensory neurons participate in nociception. Cannabinoid receptors modulate nociceptive processing in various models of pain. They are also expressed in nociceptive sensory neurons. We have examined the effect of cannabinoids on the slow P2X2 and P2X2/3 receptors in the cells isolated from nodosal and dorsal root ganglia of rat. The study was carried out by means of the whole-cell patch clamp and rapid superfusion methods. We have found that both endogenous and synthetic cannabinoids (anandamide, WIN55,212-2, and (R)-(+)-methanandamide) inhibit the slow response to ATP mediated by P2X2 and P2X2/3 receptors in a majority of tested neurons. This inhibition was significant but only partial: anandamide (0.5-1 microM) inhibited the response to 51+/-21% of control. In the remaining minority of tested neurons, the response was transiently facilitated. The effect of cannabinoids appears to be mediated via cannabinoid CB(1) receptors: it was reversibly inhibited by selective CB(1) antagonist, SR141716A (10 microM). Introduction of cyclic AMP (0.5 mM) into the cell potently facilitated the inhibitory effect of cannabinoids: the ATP-activated current was inhibited to 13+/-10% of control. These data indicate that cannabinoids may inhibit nociceptive responses produced by P2X receptors.
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Affiliation(s)
- O Krishtal
- Department of Cellular Membranology, Bogomoletz Institute of Physiology, Bogomoletz Street 4, Kiev, 01024, Ukraine.
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19
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Fisyunov A, Tsintsadze V, Min R, Burnashev N, Lozovaya N. Cannabinoids modulate the P-type high-voltage-activated calcium currents in purkinje neurons. J Neurophysiol 2006; 96:1267-77. [PMID: 16738209 DOI: 10.1152/jn.01227.2005] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Endocannabinoids released by postsynaptic cells inhibit neurotransmitter release in many central synapses by activating presynaptic cannabinoid CB1 receptors. In particular, in the cerebellum, endocannabinoids inhibit synaptic transmission at granule cell to Purkinje cell synapses by modulating presynaptic calcium influx via N-, P/Q-, and R-type calcium channels. Using whole cell patch-clamp techniques, we show that in addition to this presynaptic action, both synthetic and endogenous cannabinoids inhibit P-type calcium currents in isolated rat Purkinje neurons independent of CB1 receptor activation. The IC50 for the anandamide (AEA)-induced inhibition of P-current peak amplitude was 1.04 +/- 0.04 microM. In addition, we demonstrate that all the tested cannabinoids in a physiologically relevant range of concentrations strongly accelerate inactivation of P currents. The effects of AEA cannot be attributed to the metabolism of AEA because a nonhydrolyzing analogue of AEA, methanandamide inhibited P-type currents with a similar efficacy. All effects of cannabinoids on P-type Ca2+ currents were insensitive to antagonists of CB1 cannabinoid or vanilloid TRPV1 receptors. In cerebellar slices, WIN 55,212-2 significantly affected spontaneous firing of Purkinje neurons in the presence of CB1 receptor antagonist, in a manner similar to that of a specific P-type channel antagonist, indicating a possible functional implication of the direct effects of cannabinoids on P current. Taken together these findings demonstrate a functionally important direct action of cannabinoids on P-type calcium currents.
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Affiliation(s)
- Alexander Fisyunov
- Department of Cellular Membranology, Bogomoletz Institute of Physiology, 4 Bogomoletz St., Kyiv 01024, Ukraine
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20
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Melnik S, Wright M, Tanner JA, Tsintsadze T, Tsintsadze V, Miller AD, Lozovaya N. Diadenosine polyphosphate analog controls postsynaptic excitation in CA3-CA1 synapses via a nitric oxide-dependent mechanism. J Pharmacol Exp Ther 2006; 318:579-88. [PMID: 16709679 DOI: 10.1124/jpet.105.097642] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Previously, we have described the modulatory effect of diadenosine polyphosphates Ap4A and Ap5A on synaptic transmission in the rat hippocampal slices mediated by presynaptic receptors (Klishin et al., 1994). In contrast, we now describe how nonhydrolyzable Ap4A analog diadenosine-5',5'''-P1,P4-[beta,beta'-methylene]tetraphosphate (AppCH2ppA) at low micromolar concentrations exerts strong nondesensitizing inhibition of orthodromically evoked field potentials (OFPs) without affecting the amplitude of excitatory postsynaptic currents and antidromically evoked field potentials, as recorded in hippocampal CA1 zone. The effects of AppCH2ppA on OFPs are eliminated by a P2 receptor antagonist pyridoxal-phosphate-6-azophenyl-2',4'-disulfonic acid (PPADS) but not mimicked by purinoceptor agonists alpha,beta-methylene-ATP and adenosine 5'-O-(3-thio)-triphosphate, indicating that a P2-like receptor is involved but not one belonging to the conventional P2X/P2Y receptor classes. Diadenosine polyphosphate receptor (P4) antagonist Ip4I (diinosine tetraphosphate) was unable to modulate AppCH2ppA effects. Thus, the PPADS-sensitive P2-like receptor for AppCH2ppA seems to control selectively dendritic excitation of the CA1 neurons. The specific nitric oxide (NO)-scavenger 2-phenyl-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide is shown to significantly attenuate AppCH2ppA-mediated inhibitory effects, indicating that NO is involved in the cascade of events initiated by AppCH2ppA. Further downstream mediation by adenosine A1 receptors is also demonstrated. Hence, AppCH2ppA-mediated effects involve PPADS-sensitive P2-like receptor activation leading to the production of NO that stimulates intracellular synthesis of adenosine, causing in turn postsynaptic A1 receptor activation and subsequent postsynaptic CA1 dendritic inhibition. Such spatially selective postsynaptic dendritic inhibition may influence dendritic electrogenesis in pyramidal neurons and consequently mediate control of neuronal network activity.
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Affiliation(s)
- Sergei Melnik
- Department of Cellular Membranology, Bogomoletz Institute of Physiology, Kiev, Ukraine, Russia
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Abstract
At many central synapses, endocannabinoids released by postsynaptic cells act retrogradely on presynaptic G-protein-coupled cannabinoid receptors to inhibit neurotransmitter release. Here, we demonstrate that cannabinoids may directly affect the functioning of inhibitory glycine receptor (GlyR) channels. In isolated hippocampal pyramidal and Purkinje cerebellar neurons, endogenous cannabinoids anandamide and 2-arachidonylglycerol, applied at physiological concentrations, inhibited the amplitude and altered the kinetics of rise time, desensitization, and deactivation of the glycine-activated current (I(Gly)) in a concentration-dependent manner. These effects of cannabinoids were observed in the presence of cannabinoid CB1/CB3, vanilloid receptor 1 antagonists, and the G-protein inhibitor GDPbetaS, suggesting a direct action of cannabinoids on GlyRs. The effect of cannabinoids on I(Gly) desensitization was strongly voltage dependent. We also demonstrate that, in the presence of a GABA(A) receptor antagonist, GlyRs may contribute to the generation of seizure-like activity induced by short bursts (seven stimuli) of high-frequency stimulation of inputs to hippocampal CA1 region, because this activity was diminished by selective GlyR antagonists (strychnine and ginkgolides B and J). The GlyR-mediated rhythmic activity was also reduced by cannabinoids (anandamide) in the presence of a CB1 receptor antagonist. These results suggest that the direct inhibition of GlyRs by endocannabinoids can modulate the hippocampal network activity.
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Affiliation(s)
- Natalia Lozovaya
- Department of Cellular Membranology, Bogomoletz Institute of Physiology, 01204 Kiev, Ukraine
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Andrey F, Tsintsadze T, Volkova T, Lozovaya N, Krishtal O. Acid sensing ionic channels: modulation by redox reagents. Biochim Biophys Acta 2005; 1745:1-6. [PMID: 16085050 DOI: 10.1016/j.bbamcr.2005.01.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2004] [Revised: 01/20/2005] [Accepted: 01/31/2005] [Indexed: 10/25/2022]
Abstract
Acid-sensing ion channels (ASICs) are widely expressed in mammalian sensory neurons and supposedly play a role in nociception and acid sensing. In the course of functioning the redox status of the tissue is subjected to changes. Using whole-cell patch-clamp/concentration clamp techniques we have investigated the effect of redox reagents on the ASIC-like currents in the sensory ganglia and hippocampal neurons of rat. The reducing agent dithiothreitol (DTT), when applied in the concentrations 1-2 mM, reversibly potentiates proton-activated currents, while the oxidizing reagent 5,5'-dithio-bis-(2-nitrobenzoic acid) (DTNB) causes their inhibition. The EC50 and Hill coefficient for the activation of ASIC-like currents by protons are not affected by DTT. Redox modulation of proton-activated currents is independent on the membrane potential and on the level of pH used for the current activation. The endogenous antioxidant tripeptide glutathione (its reduced form, g-l-glutamyl-l-cysteinyl-glycine, GSH) also potentiates proton-activated currents. Our results indicate that ASIC-like currents are susceptible to regulation by redox agents.
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Affiliation(s)
- Fedorenko Andrey
- Department of Cellular Membranology, Bogomoletz Institute of Physiology, Kiev, Ukraine
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23
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Fisyunov A, Pluzhnikov K, Molyavka A, Grishin E, Lozovaya N, Krishtal O. Novel spider toxin slows down the activation kinetics of P-type Ca2+ channels in Purkinje neurons of rat. Toxicology 2005; 207:129-36. [PMID: 15590128 DOI: 10.1016/j.tox.2004.09.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2004] [Revised: 09/10/2004] [Accepted: 09/10/2004] [Indexed: 10/26/2022]
Abstract
We have identified a novel polypeptide toxin (Lsp-1) from the venom of the spider Lycosa (LS). Its effect has been examined on the P-type calcium channels in Purkinje neurons, using whole-cell patch-clamp. This toxin (at saturating concentration 7 nM) produces prominent (four-fold) deceleration of the activation kinetics and partial (71+/-6%) decrease of the amplitude of P-current without affecting either deactivation or inactivation kinetics. These effects are not use-dependent. They are partially reversible within a minute upon the wash-out of the toxin. Intracellular perfusion of Purkinje neurons with 100 microM of GDP or 2 microM of GTPgammaS, as well as strong depolarising pre-pulses (+100 mV), do not eliminate the action of Lsp-1 on P-channels indicating that down-modulation via guanine nucleotide-binding proteins (G-proteins) is not involved in the observed phenomenon. In view of extremely high functional significance of P-channels, the toxin can be suggested as a useful pharmacological tool.
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Affiliation(s)
- Alexander Fisyunov
- Department of Cellular Membranology, A.A. Bogomoletz Institute of Physiology, Bogomoletz Street 4, Kiev 01024, Ukraine
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24
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Blumenstein Y, Maximyuk OP, Lozovaya N, Yatsenko NM, Kanevsky N, Krishtal O, Dascal N. Intracellular Na+ inhibits voltage-dependent N-type Ca2+ channels by a G protein betagamma subunit-dependent mechanism. J Physiol 2004; 556:121-34. [PMID: 14742725 PMCID: PMC1664899 DOI: 10.1113/jphysiol.2003.056168] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
N-type voltage-dependent Ca(2+) channels (N-VDCCs) play important roles in neurotransmitter release and certain postsynaptic phenomena. These channels are modulated by a number of intracellular factors, notably by Gbetagamma subunits of G proteins, which inhibit N-VDCCs in a voltage-dependent (VD) manner. Here we show that an increase in intracellular Na(+) concentration inhibits N-VDCCs in hippocampal pyramidal neurones and in Xenopus oocytes. In acutely dissociated hippocampal neurones, Ba(2+) current via N-VDCCs was inhibited by Na(+) influx caused by the activation of NMDA receptor channels. In Xenopus oocytes expressing N-VDCCs, Ba(2+) currents were inhibited by Na(+) influx and enhanced by depletion of Na(+), after incubation in a Na(+)-free extracellular solution. The Na(+)-induced inhibition was accompanied by the development of VD facilitation, a hallmark of a Gbetagamma-dependent process. Na(+)-induced regulation of N-VDCCs is Gbetagamma dependent, as suggested by the blocking of Na(+) effects by Gbetagamma scavengers and by excess Gbetagamma, and may be mediated by the Na(+)-induced dissociation of Galphabetagamma heterotrimers. N-VDCCs may be novel effectors of Na(+)ion, regulated by the Na(+) concentration via Gbetagamma.
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Affiliation(s)
- Yakov Blumenstein
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Ramat Aviv 69978, Israel.
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Maximyuk O, Khmyz V, Lozovaya N, Dascal N, Krishtal O. NEUROPHYSIOLOGY+ 2002; 34:182-183. [DOI: 10.1023/a:1020747131908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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26
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Krishtal O, Lozovaya N, Fisunov A, Tsintsadze T, Pankratov Y, Kopanitsa M, Chatterjee SS. Modulation of ion channels in rat neurons by the constituents of Hypericum perforatum. Pharmacopsychiatry 2001; 34 Suppl 1:S74-82. [PMID: 11518081 DOI: 10.1055/s-2001-15510] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Despite almost forty years of widespread use of antidepressant drugs, their mode of action is still unknown. Hyperforin, a phloroglucinol derivative, is a major pharmacologically and therapeutically active constituent of Hypericum perforatum extract that is widely used as an herbal antidepressant drug. However, the mechanism or mechanisms of action of these naturally abundant, non-toxic extracts remain unclear. Enzymatically isolated patch-clamped rat central and peripheral neurons exposed to rapid changes in the composition of external medium (concentration clamp) were used in our experiments to investigate the modulation of the various voltage- and ligand-gated channels by hyperforin, as well as by other constituents of Hypericum perforatum. At nanomolar concentrations, hyperforin induced significant inhibition of various ion channels. In the case of P-type Ca2+ channels, we established that hyperforin acts via interaction with calmodulin or through calmodulin-activated pathways involving at least one second messenger. The results presented here indicate that multiple mechanisms and extract constituents may be involved in the antidepressant action of Hypericum extracts, and that they could also possess neuroprotective and analgesic effects.
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Affiliation(s)
- O Krishtal
- Bogomoletz Institute of Physiology, Kiev, Ukraine.
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Krishtal O, Kirichok Y, Tsintsadze T, Lozovaya N, Loesel W, Arndts D. New channel blocker BIIA388CL blocks delayed rectifier, but not A-type potassium current in central neurons. Neuropharmacology 2001; 40:233-41. [PMID: 11114402 DOI: 10.1016/s0028-3908(00)00150-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A new substance (R,S)-(3,4-dihydro-6,7-dimethoxyisoquinoline-1-yl)-2-cyclohexyl-N-(3,3-diphenylpropyl)-acetamide hydrochloride (BIIA388Cl), which demonstrates neuroprotective properties in animal models, was examined for its action on K(+) currents in acutely isolated rat hippocampal neurons using the patch-clamp/concentration clamp techniques in the whole-cell configuration. The delayed rectifier K(+)-current (I(DR)) was strongly inhibited by externally applied BIIA388Cl, while the transient A-current (I(A)) remained virtually unaffected. Block of I(DR) by the pre-applied BIIA388Cl was revealed as a rapid decay of the current indicating direct interaction of the drug with the open state of the channel. The removal of the block upon repolarization was also rapid (tau=22 ms). The dose-response relationship for the blocking action of BIIA388Cl revealed an IC(50) value of 300 nM for the peak I(DR), whereas the IC(50) value for I(DR) measured 300 ms after the onset of depolarization was 120 nM. The blocking action of BIIA388Cl on I(A) was at least 200 times less potent. These data allow us to conclude that BIIA388Cl is an effective and selective blocker of I(DR). This current is the main pathway for the loss of intracellular potassium by depolarized neurons. Selective obstruction of this pathway could be useful for neuroprotection.
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Affiliation(s)
- O Krishtal
- Bogomoletz Institute of Physiology, Department of Cellular Membranology, Bogomoletz str., 4, Kyiv, Ukraine, 01024.
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Fisunov A, Lozovaya N, Tsintsadze T, Chatterjee S, Nöldner M, Krishtal O. Hyperforin modulates gating of P-type Ca2+ current in cerebellar Purkinje neurons. Pflugers Arch 2000; 440:427-34. [PMID: 10954328 DOI: 10.1007/s004240000306] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Whole-cell, patch-clamp recordings from acutely isolated cerebellar Purkinje neurons demonstrate a two-stage modulation of P-type high-voltage-activated (HVA) Ca2+ current by a constituent of St. John's wort, hyperforin (0.04-0.8 microM). The first stage of modulation was voltage dependent and reversible. It comprised slow-down of the activation kinetics and a shift in the voltage dependence of P-current to more negative voltages. Hyperforin (0.8 microM) shifted the maximum of the current/voltage (I/V) relationship by -8+/-2 mV. The second, voltage-independent stage of modulation was manifested as a slowly developing inhibition of P-current that could not be reversed within the period of study. Neither form of modulation was abolished by intracellular guanosine 5'-O-(2-thiodiphosphate) (GDPPS) or guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS) or by strong depolarising pre-pulses, indicating that modulation via guanine nucleotide-binding proteins (G proteins) is not involved in the observed phenomenon. Calmidazolium (0.5 microM), an antagonist of the intracellular Ca2+-binding protein calmodulin significantly inhibited the hyperforin-induced shift of the IIV curve maximum and the slow-down of the activation kinetics. It did not, however, affect the delayed inhibition of P-current, indicating that the two stages of modulation are mediated by separate mechanisms.
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Affiliation(s)
- A Fisunov
- Department of Cellular Membranology, Bogomoletz Institute of Physiology, Kiev, Ukraine
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29
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Abstract
Using an in situ patch clamp in hippocampal CA1 mini-slices, we measured excitatory postsynaptic currents (EPSC) by varying the strength of the stimulus applied to the axons of CA3 neurones. The kinetics of the EPSC was initially independent of the stimulus strength. Post-ischaemic potentiation of the EPSC was observed 60-80 min after brief periods (10 min) of anoxia/aglycaemia. The decay of the EPSC slowed significantly in most of the examined neurones. In 11 of 17 cells the EPSC kinetics became dependent on stimulus strength: a slower decay corresponded to a stronger stimulus. This effect was not abolished by N-methyl-D-aspartate (NMDA) or a non-NMDA receptor blocker (D-2-amino-5-phosphonovaleric acid or 6-cyano-7-nitroquinoxaline-2,3-dione respectively) indicating the polysynaptic nature of the modified EPSC: transient ischaemia led to the long-term recruitment of previously inactive, possibly latent NMDA synapses between CA1 neurones.
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Affiliation(s)
- T Tsintsadze
- Department of Cellular Membranology, Bogomoletz Institute of Physiology, Kiev, Ukraine
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30
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Klishin A, Tsintsadze T, Lozovaya N, Krishtal O. Latent N-methyl-D-aspartate receptors in the recurrent excitatory pathway between hippocampal CA1 pyramidal neurons: Ca(2+)-dependent activation by blocking A1 adenosine receptors. Proc Natl Acad Sci U S A 1995; 92:12431-5. [PMID: 8618915 PMCID: PMC40371 DOI: 10.1073/pnas.92.26.12431] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
When performed at increased external [Ca2+]/[Mg2+] ratio (2.5 mM/0.5 mM), temporary block of A1 adenosine receptors in hippocampus [by 8-cyclopentyltheophylline (CPT)] leads to a dramatic and irreversible change in the excitatory postsynaptic current (EPSC) evoked by Schaffer collateral/commissural (SCC) stimulation and recorded by in situ patch clamp in CA1 pyramidal neurons. The duration of the EPSC becomes stimulus dependent, increasing with increase in stimulus strength. The later occurring component of the EPSC is carried through N-methyl-D-aspartate (NMDA) receptor-operated channels but disappears under either the NMDA antagonist 2-amino-5-phosphonovaleric acid (APV) or the non-NMDA antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). These findings indicate that the late component of the SCC-evoked EPSC is polysynaptic: predominantly non-NMDA receptor-mediated SCC inputs excite CA1 neurons that recurrently excite each other by predominantly NDMA receptor-mediated synapses. These recurrent connections are normally silent but become active after CPT treatment, leading to enhancement of the late component of the EPSC. The activity of these connections is maintained for at least 2 hr after CPT removal. When all functional NMDA receptors are blocked by dizocilpine maleate (MK-801), subsequent application of CPT leads to a partial reappearance of NMDA receptor-mediated EPSCs evoked by SCC stimulation, indicating that latent NMDA receptors are recruited. Altogether, these findings indicate the existence of a powerful system of NMDA receptor-mediated synaptic contacts in SCC input to hippocampal CA1 pyramidal neurons and probably also in reciprocal connections between these neurons, which in the usual preparation are kept latent by activity of A1 receptors.
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Affiliation(s)
- A Klishin
- Department of Cellular Membranology, Bogomoletz Institute of Physiology, Kiev, Ukraine
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31
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Klishin A, Lozovaya N, Krishtal O. A1 adenosine receptors differentially regulate the N-methyl-D-aspartate and non-N-methyl-D-aspartate receptor-mediated components of hippocampal excitatory postsynaptic current in a Ca2+/Mg(2+)-dependent manner. Neuroscience 1995; 65:947-53. [PMID: 7542373 DOI: 10.1016/0306-4522(94)00518-a] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A1 adenosine receptors efficiently modulate the excitatory synaptic transmission in hippocampus. Here we report that in addition to previously known modulatory action on the synaptic efficacy, A1 adenosine receptors are also capable of regulating the relative contribution of N-methyl-D-aspartate receptor-mediated component of the excitatory postsynaptic current in CA3-CA1 excitatory synapses, in the rat. When applied externally, a selective A1 adenosine receptor antagonist, 8-cyclopentyl-1,3-dimethylxanthine, increases not only the amplitude of excitatory postsynaptic current but also the relative contribution of the N-methyl-D-aspartate receptor-mediated component of postsynaptic current recorded by in situ voltage clamp. This effect develops only at increased external Ca2+ concentration and also depends on the external Ca2+/Mg2+ ratio. The increased ratio of N-methyl-D-aspartate/non-N-methyl-D-aspartate components of excitatory postsynaptic current remains at a new level after the removal of 8-cyclopentyl-1,3-dimethylxanthine, even though the amplitude of excitatory postsynaptic current returns close to control value. These results indicate the existence of a mechanism that preferentially enhances the N-methyl-D-aspartate component of excitatory postsynaptic current when the A1 adenosine receptors are blocked and imprints the newly acquired ratio of corresponding excitatory postsynaptic current components.
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Affiliation(s)
- A Klishin
- Department of Physico-Chemical Biology of Cellular Membranes, Bogomoletz Institute of Physiology, Kiev, Ukraine
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Klishin A, Lozovaya N, Krishtal O. Persistently enhanced ratio of NMDA and non-NMDA components of rat hippocampal EPSC after block of A1 adenosine receptors at increased [Ca2+]o/[Mg2+]o. Neurosci Lett 1994; 179:132-6. [PMID: 7531310 DOI: 10.1016/0304-3940(94)90952-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
NMDA and non-NMDA receptor-mediated components of excitatory post-synaptic current (EPSC) were studied by in situ whole-cell voltage-clamp recordings in the CA1 field of rat hippocampus. We found that the amplitudes ratio of the NMDA to the non-NMDA components can be strongly increased by blocking A1 adenosine receptors. The necessary conditions for this effect are both, increased Ca2+ and lowered Mg2+ in the external medium. The so achieved increase in the NMDA/non-NMDA ratio of EPSC components is irreversible and no longer depends on the activity of A1 adenosine receptors.
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Affiliation(s)
- A Klishin
- Department of Physico-Chemical Biology of Cellular Membranes, Bogomoletz Institute of Physiology, Kiev, Ukraine
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Klishin A, Lozovaya N, Pintor J, Miras-Portugal MT, Krishtal O. Possible functional role of diadenosine polyphosphates: negative feedback for excitation in hippocampus. Neuroscience 1994; 58:235-6. [PMID: 8152536 DOI: 10.1016/0306-4522(94)90030-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Diadenosine polyphosphates (Ap4A and Ap5A) are present in secretory granules of chromaffin cells as well as in the rat brain synaptic terminals. Their contribution to the exocytosis of the total synaptosomal content is considerable, ranging from 7% to 12%. Ap4A and Ap5A are released from synaptosomes in a Ca(2+)-dependent manner. There are indications on the high affinity of diadenosine polyphosphates to P2 receptors, but their action on P1 receptors remains unclear. Here we report that both substances induce a blocking action on excitatory synaptic transmission in the rat hippocampus. This action is elicited via the A1 (subclass of P1) receptors and differs in some respects from the action of adenosine.
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Affiliation(s)
- A Klishin
- Bogomoletz Institute of Physiology, Kiev, Ukraine
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