1
|
Juvenal G, Higa GSV, Bonfim Marques L, Tessari Zampieri T, Costa Viana FJ, Britto LR, Tang Y, Illes P, di Virgilio F, Ulrich H, de Pasquale R. Regulation of GABAergic neurotransmission by purinergic receptors in brain physiology and disease. Purinergic Signal 2024:10.1007/s11302-024-10034-x. [PMID: 39046648 DOI: 10.1007/s11302-024-10034-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 06/19/2024] [Indexed: 07/25/2024] Open
Abstract
Purinergic receptors regulate the processing of neural information in the hippocampus and cerebral cortex, structures related to cognitive functions. These receptors are activated when astrocytic and neuronal populations release adenosine triphosphate (ATP) in an autocrine and paracrine manner, following sustained patterns of neuronal activity. The modulation by these receptors of GABAergic transmission has only recently been studied. Through their ramifications, astrocytes and GABAergic interneurons reach large groups of excitatory pyramidal neurons. Their inhibitory effect establishes different synchronization patterns that determine gamma frequency rhythms, which characterize neural activities related to cognitive processes. During early life, GABAergic-mediated synchronization of excitatory signals directs the experience-driven maturation of cognitive development, and dysfunctions concerning this process have been associated with neurological and neuropsychiatric diseases. Purinergic receptors timely modulate GABAergic control over ongoing neural activity and deeply affect neural processing in the hippocampal and neocortical circuitry. Stimulation of A2 receptors increases GABA release from presynaptic terminals, leading to a considerable reduction in neuronal firing of pyramidal neurons. A1 receptors inhibit GABAergic activity but only act in the early postnatal period when GABA produces excitatory signals. P2X and P2Y receptors expressed in pyramidal neurons reduce the inhibitory tone by blocking GABAA receptors. Finally, P2Y receptor activation elicits depolarization of GABAergic neurons and increases GABA release, thus favoring the emergence of gamma oscillations. The present review provides an overall picture of purinergic influence on GABAergic transmission and its consequences on neural processing, extending the discussion to receptor subtypes and their involvement in the onset of brain disorders, including epilepsy and Alzheimer's disease.
Collapse
Affiliation(s)
- Guilherme Juvenal
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, SP, Brazil
| | - Guilherme Shigueto Vilar Higa
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, SP, Brazil
- Department of Biophysics and Physiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Lucas Bonfim Marques
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, SP, Brazil
| | - Thais Tessari Zampieri
- Department of Biophysics and Physiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Felipe José Costa Viana
- Department of Biophysics and Physiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Luiz R Britto
- Department of Biophysics and Physiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Yong Tang
- International Joint Research Centre On Purinergic Signalling, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
| | - Peter Illes
- International Joint Research Centre On Purinergic Signalling, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
- School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
- Rudolf Boehm Institute for Pharmacology and Toxicology, University of Leipzig, 04107, Leipzig, Germany
| | | | - Henning Ulrich
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, SP, Brazil.
- International Joint Research Centre On Purinergic Signalling, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China.
| | - Roberto de Pasquale
- Department of Biophysics and Physiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
| |
Collapse
|
2
|
Kok M, Brodsky JL. The biogenesis of potassium transporters: implications of disease-associated mutations. Crit Rev Biochem Mol Biol 2024:1-45. [PMID: 38946646 DOI: 10.1080/10409238.2024.2369986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Accepted: 06/16/2024] [Indexed: 07/02/2024]
Abstract
The concentration of intracellular and extracellular potassium is tightly regulated due to the action of various ion transporters, channels, and pumps, which reside primarily in the kidney. Yet, potassium transporters and cotransporters play vital roles in all organs and cell types. Perhaps not surprisingly, defects in the biogenesis, function, and/or regulation of these proteins are linked to range of catastrophic human diseases, but to date, few drugs have been approved to treat these maladies. In this review, we discuss the structure, function, and activity of a group of potassium-chloride cotransporters, the KCCs, as well as the related sodium-potassium-chloride cotransporters, the NKCCs. Diseases associated with each of the four KCCs and two NKCCs are also discussed. Particular emphasis is placed on how these complex membrane proteins fold and mature in the endoplasmic reticulum, how non-native forms of the cotransporters are destroyed in the cell, and which cellular factors oversee their maturation and transport to the cell surface. When known, we also outline how the levels and activities of each cotransporter are regulated. Open questions in the field and avenues for future investigations are further outlined.
Collapse
Affiliation(s)
- Morgan Kok
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| |
Collapse
|
3
|
Witkin JM, Shafique H, Cerne R, Smith JL, Marini AM, Lipsky RH, Delery E. Mechanistic and therapeutic relationships of traumatic brain injury and γ-amino-butyric acid (GABA). Pharmacol Ther 2024; 256:108609. [PMID: 38369062 DOI: 10.1016/j.pharmthera.2024.108609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 01/18/2024] [Accepted: 02/01/2024] [Indexed: 02/20/2024]
Abstract
Traumatic brain injury (TBI) is a highly prevalent medical condition for which no medications specific for the prophylaxis or treatment of the condition as a whole exist. The spectrum of symptoms includes coma, headache, seizures, cognitive impairment, depression, and anxiety. Although it has been known for years that the inhibitory neurotransmitter γ-amino-butyric acid (GABA) is involved in TBI, no novel therapeutics based upon this mechanism have been introduced into clinical practice. We review the neuroanatomical, neurophysiological, neurochemical, and neuropharmacological relationships of GABA neurotransmission to TBI with a view toward new potential GABA-based medicines. The long-standing idea that excitatory and inhibitory (GABA and others) balances are disrupted by TBI is supported by the experimental data but has failed to invent novel methods of restoring this balance. The slow progress in advancing new treatments is due to the complexity of the disorder that encompasses multiple dynamically interacting biological processes including hemodynamic and metabolic systems, neurodegeneration and neurogenesis, major disruptions in neural networks and axons, frank brain lesions, and a multitude of symptoms that have differential neuronal and neurohormonal regulatory mechanisms. Although the current and ongoing clinical studies include GABAergic drugs, no novel GABA compounds are being explored. It is suggested that filling the gap in understanding the roles played by specific GABAA receptor configurations within specific neuronal circuits could help define new therapeutic approaches. Further research into the temporal and spatial delivery of GABA modulators should also be useful. Along with GABA modulation, research into the sequencing of GABA and non-GABA treatments will be needed.
Collapse
Affiliation(s)
- Jeffrey M Witkin
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent Hospital, Indianapolis, IN, USA; Departments of Neuroscience and Trauma Research, Ascension St. Vincent Hospital, Indianapolis, IN, USA; RespireRx Pharmaceuticals Inc, Glen Rock, NJ, USA.
| | | | - Rok Cerne
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent Hospital, Indianapolis, IN, USA; RespireRx Pharmaceuticals Inc, Glen Rock, NJ, USA; Department of Anatomy and Cell Biology, Indiana University/Purdue University, Indianapolis, IN, USA
| | - Jodi L Smith
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent Hospital, Indianapolis, IN, USA
| | - Ann M Marini
- Department of Neurology, Program in Neuroscience, and Molecular and Cellular Biology Program, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Robert H Lipsky
- Department of Neurology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Elizabeth Delery
- College of Osteopathic Medicine, Marian University, Indianapolis, IN, USA.
| |
Collapse
|
4
|
Kok M, Hartnett-Scott K, Happe CL, MacDonald ML, Aizenman E, Brodsky JL. The expression system influences stability, maturation efficiency, and oligomeric properties of the potassium-chloride co-transporter KCC2. Neurochem Int 2024; 174:105695. [PMID: 38373478 PMCID: PMC10923169 DOI: 10.1016/j.neuint.2024.105695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 02/02/2024] [Accepted: 02/06/2024] [Indexed: 02/21/2024]
Abstract
The neuron-specific K+/Cl- co-transporter 2, KCC2, which is critical for brain development, regulates γ-aminobutyric acid-dependent inhibitory neurotransmission. Consistent with its function, mutations in KCC2 are linked to neurodevelopmental disorders, including epilepsy, schizophrenia, and autism. KCC2 possesses 12 transmembrane spans and forms an intertwined dimer. Based on its complex architecture and function, reduced cell surface expression and/or activity have been reported when select disease-associated mutations are present in the gene encoding the protein, SLC12A5. These data suggest that KCC2 might be inherently unstable, as seen for other complex polytopic ion channels, thus making it susceptible to cellular quality control pathways that degrade misfolded proteins. To test these hypotheses, we examined KCC2 stability and/or maturation in five model systems: yeast, HEK293 cells, primary rat neurons, and rat and human brain synaptosomes. Although studies in yeast revealed that KCC2 is selected for endoplasmic reticulum-associated degradation (ERAD), experiments in HEK293 cells supported a more subtle role for ERAD in maintaining steady-state levels of KCC2. Nevertheless, this system allowed for an analysis of KCC2 glycosylation in the ER and Golgi, which serves as a read-out for transport through the secretory pathway. In turn, KCC2 was remarkably stable in primary rat neurons, suggesting that KCC2 folds efficiently in more native systems. Consistent with these data, the mature glycosylated form of KCC2 was abundant in primary rat neurons as well as in rat and human brain. Together, this work details the first insights into the influence that the cellular and membrane environments have on several fundamental KCC2 properties, acknowledges the advantages and disadvantages of each system, and helps set the stage for future experiments to assess KCC2 in a normal or disease setting.
Collapse
Affiliation(s)
- Morgan Kok
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Karen Hartnett-Scott
- Department of Neurobiology and the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Cassandra L Happe
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Matthew L MacDonald
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Elias Aizenman
- Department of Neurobiology and the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA.
| |
Collapse
|
5
|
De Araujo Furtado M, Aroniadou-Anderjaska V, Figueiredo TH, Pidoplichko VI, Apland JP, Rossetti K, Braga MFM. Preventing Long-Term Brain Damage by Nerve Agent-Induced Status Epilepticus in Rat Models Applicable to Infants: Significant Neuroprotection by Tezampanel Combined with Caramiphen but Not by Midazolam Treatment. J Pharmacol Exp Ther 2024; 388:432-450. [PMID: 37739807 PMCID: PMC10801760 DOI: 10.1124/jpet.123.001710] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 07/25/2023] [Accepted: 07/31/2023] [Indexed: 09/24/2023] Open
Abstract
Acute exposure to nerve agents induces a peripheral cholinergic crisis and prolonged status epilepticus (SE), causing death or long-term brain damage. To provide preclinical data pertinent to the protection of infants and newborns, we compared the antiseizure and neuroprotective effects of treating soman-induced SE with midazolam (MDZ) versus tezampanel (LY293558) in combination with caramiphen (CRM) in 12- and 7-day-old rats. The anticonvulsants were administered 1 hour after soman exposure; neuropathology data were collected up to 6 months postexposure. In both ages, the total duration of SE within 24 hours after soman exposure was significantly shorter in the LY293558 plus CRM groups compared with the MDZ groups. Neuronal degeneration was substantial in the MDZ-treated groups but absent or minimal in the groups treated with LY293558 plus CRM. Loss of neurons and interneurons in the basolateral amygdala and CA1 hippocampal area was significant in the MDZ-treated groups but virtually absent in the LY293558 plus CRM groups. Atrophy of the amygdala and hippocampus occurred only in MDZ-treated groups. Neuronal/interneuronal loss and atrophy of the amygdala and hippocampus deteriorated over time. Reduction of inhibitory activity in the basolateral amygdala and increased anxiety were found only in MDZ groups. Spontaneous recurrent seizures developed in the MDZ groups, deteriorating over time; a small percentage of rats from the LY293558 plus CRM groups also developed seizures. These results suggest that brain damage can be long lasting or permanent if nerve agent-induced SE in infant victims is treated with midazolam at a delayed timepoint after SE onset, whereas antiglutamatergic treatment with tezampanel and caramiphen provides significant neuroprotection. SIGNIFICANCE STATEMENT: To protect the brain and the lives of infants in a mass exposure to nerve agents, an anticonvulsant treatment must be administered that will effectively stop seizures and prevent neuropathology, even if offered with a relative delay after seizure onset. The present study shows that midazolam, which was recently approved by the Food and Drug Administration for the treatment of nerve agent-induced status epilepticus, is not an effective neuroprotectant, whereas brain damage can be prevented by targeting glutamate receptors.
Collapse
Affiliation(s)
- Marcio De Araujo Furtado
- Departments of Anatomy, Physiology, and Genetics (M.D.A.F., V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neuroscience Branch, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Gunpowder, Maryland (J.P.A.)
| | - Vassiliki Aroniadou-Anderjaska
- Departments of Anatomy, Physiology, and Genetics (M.D.A.F., V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neuroscience Branch, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Gunpowder, Maryland (J.P.A.)
| | - Taiza H Figueiredo
- Departments of Anatomy, Physiology, and Genetics (M.D.A.F., V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neuroscience Branch, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Gunpowder, Maryland (J.P.A.)
| | - Volodymyr I Pidoplichko
- Departments of Anatomy, Physiology, and Genetics (M.D.A.F., V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neuroscience Branch, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Gunpowder, Maryland (J.P.A.)
| | - James P Apland
- Departments of Anatomy, Physiology, and Genetics (M.D.A.F., V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neuroscience Branch, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Gunpowder, Maryland (J.P.A.)
| | - Katia Rossetti
- Departments of Anatomy, Physiology, and Genetics (M.D.A.F., V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neuroscience Branch, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Gunpowder, Maryland (J.P.A.)
| | - Maria F M Braga
- Departments of Anatomy, Physiology, and Genetics (M.D.A.F., V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland; and Neuroscience Branch, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Gunpowder, Maryland (J.P.A.)
| |
Collapse
|
6
|
Tescarollo FC, Valdivia D, Chen S, Sun H. Unilateral optogenetic kindling of hippocampus leads to more severe impairments of the inhibitory signaling in the contralateral hippocampus. Front Mol Neurosci 2023; 16:1268311. [PMID: 37942301 PMCID: PMC10627882 DOI: 10.3389/fnmol.2023.1268311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 09/20/2023] [Indexed: 11/10/2023] Open
Abstract
The kindling model has been used extensively by researchers to study the neurobiology of temporal lobe epilepsy (TLE) due to its capacity to induce intensification of seizures by the progressive recruitment of additional neuronal clusters into epileptogenic networks. We applied repetitive focal optogenetic activation of putative excitatory neurons in the dorsal CA1 area of the hippocampus of mice to investigate the role of inhibitory signaling during this process. This experimental protocol resulted in a kindling phenotype that was maintained for 2 weeks after the animals were fully kindled. As a result of the different phases of optogenetic kindling (OpK), key inhibitory signaling elements, such as KCC2 and NKCC1, exhibited distinct temporal and spatial dynamics of regulation. These alterations in protein expression were related to the distinct pattern of ictal activity propagation through the different hippocampal sublayers. Our results suggest the KCC2 disruption in the contralateral hippocampus of fully kindled animals progressively facilitated the creation of pathological pathways for seizure propagation through the hippocampal network. Upon completion of kindling, we observed animals that were restimulated after a rest period of 14-day showed, besides a persistent KCC2 downregulation, an NKCC1 upregulation in the bilateral dentate gyrus and hippocampus-wide loss of parvalbumin-positive interneurons. These alterations observed in the chronic phase of OpK suggest that the hippocampus of rekindled animals continued to undergo self-modifications during the rest period. The changes resulting from this period suggest the possibility of the development of a mirror focus on the hippocampus contralateral to the site of optical stimulations. Our results offer perspectives for preventing the recruitment and conversion of healthy neuronal networks into epileptogenic ones among patients with epilepsy.
Collapse
Affiliation(s)
| | | | | | - Hai Sun
- Department of Neurosurgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States
| |
Collapse
|
7
|
Yakovlev AV, Kurmashova E, Gataulina E, Gerasimova E, Khalilov I, Sitdikova GF. Maternal hyperhomocysteinemia increases seizures susceptibility of neonatal rats. Life Sci 2023; 329:121953. [PMID: 37467884 DOI: 10.1016/j.lfs.2023.121953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 07/13/2023] [Accepted: 07/14/2023] [Indexed: 07/21/2023]
Abstract
AIMS Neonatal seizures are severe pathologies which may result in long-term neurological consequences. High plasma concentrations of homocysteine - hyperhomocysteinemia (hHCy) - are associated with epilepsy. In the present study, we evaluated susceptibility to seizure of neonatal rats with prenatal hHCy. MAIN METHODS Prenatal hHCy was induced by feeding females with a high-methionine diet. Experiments were performed on pups during the first three postnatal weeks. Flurothyl-induced epileptic behavior was assessed according to Racine's scale. Epileptiform activity in the hippocampus was recorded using electrophysiological methods. The balance of excitation/inhibition, functional GABAergic inhibition and GABA reversal potential in hippocampal neurons were analyzed. KEY FINDINGS Rats with hHCy developed more severe stages of behavioral patterns during flurothyl-induced epilepsy with shorter latency. Electrophysiological recordings demonstrated higher background neuronal activity in rats with hHCy. Seizure-like events triggered by flurothyl (in vivo) or 4-aminopyridine (in vitro) showed shorter latency, higher power and amplitude. An increased glutamate/GABA synaptic ratio was shown in the pyramidal neurons of rats with hHCy and more slices demonstrated excitation by isoguvacine, a selective GABA(A) receptor agonist, during the first and second postnatal weeks. The GABA driving force and the reversal potential of GABA(A) currents were more positive during the second postnatal week for hHCy rats. SIGNIFICANCE The higher susceptibility to seizures in rats with prenatal hHCy due to a shift in the balance of excitation/inhibition toward excitation may underlie the clinical evidence about the association of hHCy with an increased risk of epilepsy.
Collapse
Affiliation(s)
- A V Yakovlev
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia.
| | - E Kurmashova
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia
| | - E Gataulina
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia
| | - E Gerasimova
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia
| | - I Khalilov
- Institut de Neurobiologie de la Méditerranée, INMED UMR901 Parc scientifique de Luminy, 163 avenue de Luminy BP13 - 13273, Marseille cedex 09, France; Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia
| | - G F Sitdikova
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str 18, Kazan 420008, Russia
| |
Collapse
|
8
|
Fu N, Wang Y, Zhu R, Li N, Zeng S, Miao M, Yang Y, Sun M, Zhang J. Bicuculline and Bumetanide Attenuate Sevoflurane-Induced Impairment of Myelination and Cognition in Young Mice. ACS Chem Neurosci 2023; 14:1146-1155. [PMID: 36802490 DOI: 10.1021/acschemneuro.2c00764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Sevoflurane (Sevo) is one of the most commonly used general anesthetics for infants and young children. We investigated whether Sevo impairs neurological functions, myelination, and cognition via the γ-aminobutyric acid A receptor (GABAAR) and Na+-K+-2Cl- cotransporter (NKCC1) in neonatal mice. On postnatal days 5-7, mice were exposed to 3% Sevo for 2 h. On postnatal day 14, mouse brains were dissected, and oligodendrocyte precursor cell line level lentivirus knockdown of GABRB3, immunofluorescence, and transwell migration assays were performed. Finally, behavioral tests were conducted. Multiple Sevo exposure groups exhibited increased neuronal apoptosis levels and decreased neurofilament protein levels in the mouse cortex compared with the control group. Sevo exposure inhibited the proliferation, differentiation, and migration of the oligodendrocyte precursor cells, thereby affecting their maturation process. Electron microscopy revealed that Sevo exposure reduced myelin sheath thickness. The behavioral tests showed that multiple Sevo exposures induced cognitive impairment. GABAAR and NKCC1 inhibition provided protection against Sevo-induced neurotoxicity and cognitive dysfunction. Thus, bicuculline and bumetanide can protect against Sevo-induced neuronal injury, myelination impairment, and cognitive dysfunction in neonatal mice. Furthermore, GABAAR and NKCC1 may be mediators of Sevo-induced myelination impairment and cognitive dysfunction.
Collapse
Affiliation(s)
- Ningning Fu
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, P.R. China.,Academy of Medical Sciences of Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Yangyang Wang
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, P.R. China
| | - Ruilou Zhu
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, P.R. China
| | - Ningning Li
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, P.R. China.,Academy of Medical Sciences of Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Shuang Zeng
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, P.R. China.,Academy of Medical Sciences of Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Mengrong Miao
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, P.R. China
| | - Yitian Yang
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, P.R. China
| | - Mingyang Sun
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, P.R. China
| | - Jiaqiang Zhang
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan 450003, P.R. China
| |
Collapse
|
9
|
Saleem A, Santos AC, Aquilino MS, Sivitilli AA, Attisano L, Carlen PL. Modelling hyperexcitability in human cerebral cortical organoids: Oxygen/glucose deprivation most effective stimulant. Heliyon 2023; 9:e14999. [PMID: 37089352 PMCID: PMC10113787 DOI: 10.1016/j.heliyon.2023.e14999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 03/13/2023] [Accepted: 03/23/2023] [Indexed: 03/31/2023] Open
Abstract
Epilepsy is a common neurological disorder that affects 1% of the global population. The neonatal period constitutes the highest incidence of seizures. Despite the continual developments in seizure modelling and anti-epileptic drug development, the mechanisms involved in neonatal seizures remain poorly understood. This leaves infants with neonatal seizures at a high risk of death, poor prognosis of recovery and risk of developing neurological disorders later in life. Current in vitro platforms for modelling adult and neonatal epilepsies - namely acute cerebral brain slices or cell-derived cultures, both derived from animals-either lack a complex cytoarchitecture, high-throughput capabilities or physiological similarities to the neonatal human brain. Cerebral organoids, derived from human embryonic stem cells (hESCs), are an emerging technology that could better model neurodevelopmental disorders in the developing human brain. Herein, we study induced hyperexcitability in human cerebral cortical organoids - setting the groundwork for neonatal seizure modelling - using electrophysiological techniques and pharmacological manipulations. In neonatal seizures, energy failure - specifically due to deprivation of oxygen and glucose - is a consistent and reliable seizure induction method that has been used to study the underlying cellular and molecular mechanisms. Here, we applied oxygen-glucose deprivation (OGD) as well as common chemoconvulsants in 3-7-month-old cerebral organoids. Remarkably, OGD resulted in hyperexcitability, with increased power and spontaneous events compared to other common convulsants tested at the population level. These findings characterize OGD as the stimulus most capable of inducing hyperexcitable changes in cerebral organoid tissue, which could be extended to future modelling of neonatal epilepsies in cerebral organoids.
Collapse
|
10
|
Chloride ion dysregulation in epileptogenic neuronal networks. Neurobiol Dis 2023; 177:106000. [PMID: 36638891 DOI: 10.1016/j.nbd.2023.106000] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/25/2022] [Accepted: 01/09/2023] [Indexed: 01/13/2023] Open
Abstract
GABA is the major inhibitory neurotransmitter in the mature CNS. When GABAA receptors are activated the membrane potential is driven towards hyperpolarization due to chloride entry into the neuron. However, chloride ion dysregulation that alters the ionic gradient can result in depolarizing GABAergic post-synaptic potentials instead. In this review, we highlight that GABAergic inhibition prevents and restrains focal seizures but then reexamine this notion in the context of evidence that a static and/or a dynamic chloride ion dysregulation, that increases intracellular chloride ion concentrations, promotes epileptiform activity and seizures. To reconcile these findings, we hypothesize that epileptogenic pathologically interconnected neuron (PIN) microcircuits, representing a small minority of neurons, exhibit static chloride dysregulation and should exhibit depolarizing inhibitory post-synaptic potentials (IPSPs). We speculate that chloride ion dysregulation and PIN cluster activation may generate fast ripples and epileptiform spikes as well as initiate the hypersynchronous seizure onset pattern and microseizures. Also, we discuss the genetic, molecular, and cellular players important in chloride dysregulation which regulate epileptogenesis and initiate the low-voltage fast seizure onset pattern. We conclude that chloride dysregulation in neuronal networks appears to be critical for epileptogenesis and seizure genesis, but feed-back and feed-forward inhibitory GABAergic neurotransmission plays an important role in preventing and restraining seizures as well.
Collapse
|
11
|
Vazetdinova A, Valiullina-Rakhmatullina F, Rozov A, Evstifeev A, Khazipov R, Nasretdinov A. On the accuracy of cell-attached current-clamp recordings from cortical neurons. Front Mol Neurosci 2022; 15:979479. [PMID: 36034500 PMCID: PMC9405422 DOI: 10.3389/fnmol.2022.979479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 07/20/2022] [Indexed: 11/13/2022] Open
Abstract
Cell-attached current-clamp (CA/CC) recordings have been proposed to measure resting membrane potential and synaptic/agonist responses in neurons without disrupting the cell membrane, thus avoiding the intracellular dialysis that occurs in conventional whole-cell recordings (WC). However, the accuracy of CA/CC recordings in neurons has not been directly assessed. Here, we used concomitant CA and WC current clamp recordings from cortical neurons in brain slices. Resting membrane potential values and slow voltage shifts showed variability and were typically attenuated during CA/CC recordings by ~10–20% relative to WC values. Fast signals were slowed down and their amplitude was greatly reduced: synaptic potentials by nearly 2-fold, and action potentials by nearly 10-fold in CA/CC mode compared to WC. The polarity of GABAergic postsynaptic responses in CA/CC mode matched the responses in WC, and depolarising GABAergic potentials were predominantly observed during CA/CC recordings of intact neonatal CA3 hippocampal pyramidal neurons. Similarly, CA/CC recordings reliably detected neuronal depolarization and excitation during network-induced giant depolarizing potentials in the neonatal CA3 hippocampus, and revealed variable changes, from depolarization to hyperpolarization, in CA1 pyramidal cells during sharp wave ripples in the adult hippocampus. Thus, CA/CC recordings are suitable for assessing membrane potential but signal distortion, probably caused by leakage via the seal contact and RC filtering should be considered.
Collapse
Affiliation(s)
| | | | - Andrei Rozov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
- Institut für Physiologie und Pathophysiologie, Heidelberg, Germany
- Federal Center of Brain Research and Neurotechnologies, Moscow, Russia
| | | | - Roustem Khazipov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
- INMED - INSERM, Aix-Marseille University, Marseille, France
- *Correspondence: Roustem Khazipov
| | - Azat Nasretdinov
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
| |
Collapse
|
12
|
Figueiredo TH, Aroniadou-Anderjaska V, Pidoplichko VI, Apland JP, Braga MFM. Antiseizure and Neuroprotective Efficacy of Midazolam in Comparison with Tezampanel (LY293558) against Soman-Induced Status Epilepticus. TOXICS 2022; 10:409. [PMID: 35893842 PMCID: PMC9330837 DOI: 10.3390/toxics10080409] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 12/12/2022]
Abstract
Acute exposure to nerve agents induces status epilepticus (SE), which can cause death or long-term brain damage. Diazepam is approved by the FDA for the treatment of nerve agent-induced SE, and midazolam (MDZ) is currently under consideration to replace diazepam. However, animal studies have raised questions about the neuroprotective efficacy of benzodiazepines. Here, we compared the antiseizure and neuroprotective efficacy of MDZ (5 mg/kg) with that of tezampanel (LY293558; 10 mg/kg), an AMPA/GluK1 receptor antagonist, administered 1 h after injection of the nerve agent, soman (1.2 × LD50), in adult male rats. Both of the anticonvulsants promptly stopped SE, with MDZ having a more rapid effect. However, SE reoccurred to a greater extent in the MDZ-treated group, resulting in a significantly longer total duration of SE within 24 h post-exposure compared with the LY293558-treated group. The neuroprotective efficacy of the two drugs was studied in the basolateral amygdala, 30 days post-exposure. Significant neuronal and inter-neuronal loss, reduced ratio of interneurons to the total number of neurons, and reduction in spontaneous inhibitory postsynaptic currents accompanied by increased anxiety were found in the MDZ-treated group. The rats treated with LY293558 did not differ from the control rats (not exposed to soman) in any of these measurements. Thus, LY293558 has significantly greater efficacy than midazolam in protecting against prolonged seizures and brain damage caused by acute nerve agent exposure.
Collapse
Affiliation(s)
- Taiza H. Figueiredo
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (T.H.F.); (V.A.-A.); (V.I.P.)
| | - Vassiliki Aroniadou-Anderjaska
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (T.H.F.); (V.A.-A.); (V.I.P.)
- Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Volodymyr I. Pidoplichko
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (T.H.F.); (V.A.-A.); (V.I.P.)
| | - James P. Apland
- Neuroscience Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Aberdeen, MD 21010, USA;
| | - Maria F. M. Braga
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (T.H.F.); (V.A.-A.); (V.I.P.)
- Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| |
Collapse
|
13
|
Lin H, Lin WH, Lin F, Liu CY, Che CH, Huang HP. Potential Pleiotropic Genes and Shared Biological Pathways in Epilepsy and Depression Based on GWAS Summary Statistics. COMPUTATIONAL INTELLIGENCE AND NEUROSCIENCE 2022; 2022:6799285. [PMID: 35463244 PMCID: PMC9019309 DOI: 10.1155/2022/6799285] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 03/01/2022] [Accepted: 03/08/2022] [Indexed: 11/17/2022]
Abstract
Current epidemiological and experimental studies have indicated the overlapping genetic foundation of epilepsy and depression. However, the detailed pleiotropic genetic etiology and neurobiological pathways have not been well understood, and there are many variants with underestimated effect on the comorbidity of the two diseases. Utilizing genome-wide association study (GWAS) summary statistics of epilepsy (15,212 cases and 29,677 controls) and depression (170,756 cases and 329,443 controls) from large consortia, we assessed the integrated gene-based association with both diseases by Multimarker Analysis of Genomic Annotation (MAGMA) and Fisher's meta-analysis. On the one hand, shared genes with significantly altered transcripts in Gene Expression Omnibus (GEO) data sets were considered as possible pleiotropic genes. On the other hand, the pathway enrichment analysis was conducted based on the gene lists with nominal significance in the gene-based association test of each disease. We identified a total of two pleiotropic genes (CD3G and SLCO3A1) with gene expression analysis validated and interpreted twenty-five common biological process supported with literature mining. This study indicates the potentially shared genes associated with both epilepsy and depression based on gene expression, meta-data analysis, and pathway enrichment strategy along with traditional GWAS and provides insights into the possible intersecting pathways that were not previously reported.
Collapse
Affiliation(s)
- Han Lin
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou 350001, China
| | - Wan-Hui Lin
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou 350001, China
- Intensive Care Unit, Department of Neurology, Fujian Medical University Union Hospital, Fuzhou 350001, China
- Fujian Key Laboratory of Molecular Neurology, Fuzhou 350001, China
| | - Feng Lin
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou 350001, China
| | - Chang-Yun Liu
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou 350001, China
| | - Chun-Hui Che
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou 350001, China
| | - Hua-Pin Huang
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou 350001, China
- Intensive Care Unit, Department of Neurology, Fujian Medical University Union Hospital, Fuzhou 350001, China
- Fujian Key Laboratory of Molecular Neurology, Fuzhou 350001, China
- Department of Geriatrics, Fujian Medical University Union Hospital, Fuzhou 350001, China
| |
Collapse
|
14
|
Volnova A, Tsytsarev V, Ganina O, Vélez-Crespo GE, Alves JM, Ignashchenkova A, Inyushin M. The Anti-Epileptic Effects of Carbenoxolone In Vitro and In Vivo. Int J Mol Sci 2022; 23:ijms23020663. [PMID: 35054848 PMCID: PMC8775396 DOI: 10.3390/ijms23020663] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 01/04/2022] [Accepted: 01/06/2022] [Indexed: 12/14/2022] Open
Abstract
Gap junctions (GJs) are intercellular junctions that allow the direct transfer of ions and small molecules between neighboring cells, and GJs between astrocytes play an important role in the development of various pathologies of the brain, including regulation of the pathological neuronal synchronization underlying epileptic seizures. Recently, we found that a pathological change is observed in astrocytes during the ictal and interictal phases of 4-aminopyridin (4-AP)-elicited epileptic activity in vitro, which was correlated with neuronal synchronization and extracellular epileptic electrical activity. This finding raises the question: Does this signal depend on GJs between astrocytes? In this study we investigated the effect of the GJ blocker, carbenoxolone (CBX), on epileptic activity in vitro and in vivo. Based on the results obtained, we came to the conclusion that the astrocytic syncytium formed by GJ-associated astrocytes, which is responsible for the regulation of potassium, affects the formation of epileptic activity in astrocytes in vitro and epileptic seizure onset. This effect is probably an important, but not the only, mechanism by which CBX suppresses epileptic activity. It is likely that the mechanisms of selective inhibition of GJs between astrocytes will show important translational benefits in anti-epileptic therapies.
Collapse
Affiliation(s)
- Anna Volnova
- Biological Faculty, Saint Petersburg State University, 199034 St. Petersburg, Russia
- Institute of Translational Biomedicine, Saint Petersburg State University, 199034 St. Petersburg, Russia;
- Correspondence: (A.V.); (M.I.)
| | | | - Olga Ganina
- Nevsky Center of Scientific Collaboration, 192119 St. Petersburg, Russia;
| | - Grace E. Vélez-Crespo
- School of Medicine, Universidad Central del Caribe, Bayamon, PR 00956, USA; (G.E.V.-C.); (J.M.A.)
| | - Janaina M. Alves
- School of Medicine, Universidad Central del Caribe, Bayamon, PR 00956, USA; (G.E.V.-C.); (J.M.A.)
| | - Alla Ignashchenkova
- Institute of Translational Biomedicine, Saint Petersburg State University, 199034 St. Petersburg, Russia;
- Nevsky Center of Scientific Collaboration, 192119 St. Petersburg, Russia;
| | - Mikhail Inyushin
- School of Medicine, Universidad Central del Caribe, Bayamon, PR 00956, USA; (G.E.V.-C.); (J.M.A.)
- Correspondence: (A.V.); (M.I.)
| |
Collapse
|
15
|
Shen Y, Gong Y, Ruan Y, Chen Z, Xu C. Secondary Epileptogenesis: Common to See, but Possible to Treat? Front Neurol 2021; 12:747372. [PMID: 34938259 PMCID: PMC8686764 DOI: 10.3389/fneur.2021.747372] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 11/15/2021] [Indexed: 02/03/2023] Open
Abstract
Secondary epileptogenesis is a common phenomenon in epilepsy, characterized by epileptiform discharges from the regions outside the primary focus. It is one of the major reasons for pharmacoresistance and surgical failure. Compared with primary epileptogenesis, the mechanism of secondary epileptogenesis is usually more complex and diverse. In this review, we aim to summarize the characteristics of secondary epileptogenesis from both clinical and laboratory studies in a historical view. Mechanisms of secondary epileptogenesis in molecular, cellular, and circuity levels are further presented. Potential treatments targeting the process are discussed as well. At last, we highlight the importance of circuitry studies, which would further illustrate precise treatments of secondary epileptogenesis in the future.
Collapse
Affiliation(s)
- Yujia Shen
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, School of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China.,Key Laboratory of Medical Neurobiology of National Health Commission and Chinese Academy of Medical Sciences, Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Yiwei Gong
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, School of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China.,Key Laboratory of Medical Neurobiology of National Health Commission and Chinese Academy of Medical Sciences, Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Yeping Ruan
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, School of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China
| | - Zhong Chen
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, School of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China.,Key Laboratory of Medical Neurobiology of National Health Commission and Chinese Academy of Medical Sciences, Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Cenglin Xu
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, School of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China
| |
Collapse
|
16
|
Gamma-decanolactone attenuates acute and chronic seizures in mice: a possible role of adenosine A1 receptors. Behav Pharmacol 2021; 31:544-552. [PMID: 32701527 DOI: 10.1097/fbp.0000000000000554] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
This study aimed to investigate the possible gamma-decanolactone mechanisms of action in the GABAergic and adenosine systems using the aminophylline-induced acute crisis model and the pentylenetetrazole-induced kindling model. In the acute model, male mice received administration of bicuculline (GABAA receptor antagonist), 8-cyclopentyl-1,3-dipropylxanthine (A1 receptor antagonist) or ZM241385 (A2A receptor antagonist), 15 min before the treatment with gamma-decanolactone (300 mg/kg). After a single dose of aminophylline was administered, the animals were observed for 60 min. In the chronic model of seizure, 30 min after the treatment with gamma-decanolactone, mice received pentylenetetrazole once every third day. On the last day of kindling, the animals received the same GABA and adenosine antagonists used in the acute model, 15 min before gamma-decanolactone administration. The protein expression of GABAA α1 receptor and adenosine A1 receptor was detected using western blotting technique in hippocampal samples. The results showed that gamma-decanolactone increased the latency to first seizure and decreased seizure occurrence in the acute and chronic models. The adenosine A2A receptor antagonist and GABAA receptor antagonist were not able to change gamma-decanolactone behavioral seizure induced by aminophylline or pentylenetetrazole. The administration of adenosine A1 receptor antagonist reversed the protective effect of gamma-decanolactone in both models. In addition, gamma-decanolactone promoted an increase in the expression GABAA α1 receptor, in the hippocampus. The results suggest that the neuroprotective effect of gamma-decanolactone observed during the investigation could have a straight connection to its action on A1 adenosine receptors.
Collapse
|
17
|
Wang GY, Luan ZL, Che NW, Yan DB, Sun XW, Zhang C, Yin J. Inhibition of microRNA-129-2-3p protects against refractory temporal lobe epilepsy by regulating GABRA1. Brain Behav 2021; 11:e02195. [PMID: 34029007 PMCID: PMC8323041 DOI: 10.1002/brb3.2195] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 03/30/2021] [Accepted: 05/05/2021] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Accumulating evidence demonstrates that certain microRNAs play critical roles in epileptogenesis. Our previous studies found microRNA (miR)-129-2-3p was induced in patients with refractory temporal lobe epilepsy (TLE). In this study, we aimed to explore the role of miR-129-2-3p in TLE pathogenesis. METHOD By bioinformatics, we predicted miR-129-2-3p may target the gene GABRA1 encoding the GABA type A receptor subunit alpha 1. Luciferase assay was used to investigate the regulation of miR-129-2-3p on GABRA1 3'UTR. The dynamic expression of miR-129-2-3p and GABRA1 mRNA and protein levels were measured in primary hippocampal neurons and a rat kainic acid (KA)-induced seizure model by quantitative reverse transcription-polymerase chain reaction (qPCR), Western blotting, and immunostaining. MiR-129-2-3p agomir and antagomir were utilized to explore their role in determining GABRA1 expression. The effects of targeting miR-129-2-3p and GABRA1 on epilepsy were assessed by electroencephalography (EEG) and immunostaining. RESULTS Luciferase assay, qPCR, and Western blot results suggested GABRA1 as a direct target of miR-129-2-3p. MiR-129-2-3p level was significantly upregulated, whereas GABRA1 expression downregulated in KA-treated rat primary hippocampal neurons and KA-induced seizure model. In vivo knockdown of miR-129-2-3p by antagomir alleviated the seizure-like EEG findings in accordance with the upregulation of GABRA1. Furthermore, the seizure-suppressing effect of the antagomir was partly GABRA1 dependent. CONCLUSIONS The results suggested GABRA1 as a target of miR-129-2-3p in rat primary hippocampal neurons and a rat kainic acid (KA) seizure model. Silencing of miR-129-2-3p exerted a seizure-suppressing effect in rats. MiR-129-2-3p/GABRA1 pathway may represent a potential target for the prevention and treatment of refractory epilepsy.
Collapse
Affiliation(s)
- Guan-Yu Wang
- Department of Neurosurgery, the Second Affiliated Hospital of Dalian Medical University, Dalian, China.,Epileptic Center of Liaoning, the Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Zhi-Lin Luan
- Department of Neurosurgery, the Second Affiliated Hospital of Dalian Medical University, Dalian, China.,Advanced Institute for Medical Sciences, Dalian Medical University, Dalian, China
| | - Ning-Wei Che
- Department of Neurosurgery, the Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - De-Bin Yan
- Department of Neurosurgery, the Second Affiliated Hospital of Dalian Medical University, Dalian, China.,Epileptic Center of Liaoning, the Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Xiao-Wan Sun
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian, China
| | - Cong Zhang
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian, China
| | - Jian Yin
- Department of Neurosurgery, the Second Affiliated Hospital of Dalian Medical University, Dalian, China.,Epileptic Center of Liaoning, the Second Affiliated Hospital of Dalian Medical University, Dalian, China
| |
Collapse
|
18
|
Martynyuk AE, Ju LS, Morey TE. The potential role of stress and sex steroids in heritable effects of sevoflurane. Biol Reprod 2021; 105:735-746. [PMID: 34192761 DOI: 10.1093/biolre/ioab129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/17/2021] [Accepted: 06/25/2021] [Indexed: 12/11/2022] Open
Abstract
Most surgical procedures require general anesthesia, which is a reversible deep sedation state lacking all perception. The induction of this state is possible because of complex molecular and neuronal network actions of general anesthetics (GAs) and other pharmacological agents. Laboratory and clinical studies indicate that the effects of GAs may not be completely reversible upon anesthesia withdrawal. The long-term neurocognitive effects of GAs, especially when administered at the extremes of ages, are an increasingly recognized health concern and the subject of extensive laboratory and clinical research. Initial studies in rodents suggest that the adverse effects of GAs, whose actions involve enhancement of GABA type A receptor activity (GABAergic GAs), can also extend to future unexposed offspring. Importantly, experimental findings show that GABAergic GAs may induce heritable effects when administered from the early postnatal period to at least young adulthood, covering nearly all age groups that may have children after exposure to anesthesia. More studies are needed to understand when and how the clinical use of GAs in a large and growing population of patients can result in lower resilience to diseases in the even larger population of their unexposed offspring. This minireview is focused on the authors' published results and data in the literature supporting the notion that GABAergic GAs, in particular sevoflurane, may upregulate systemic levels of stress and sex steroids and alter expressions of genes that are essential for the functioning of these steroid systems. The authors hypothesize that stress and sex steroids are involved in the mediation of sex-specific heritable effects of sevoflurane.
Collapse
Affiliation(s)
- Anatoly E Martynyuk
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, USA.,McKnight Brain Institute, University of Florida College of Medicine, Gainesville, FL, USA
| | - Ling-Sha Ju
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Timothy E Morey
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, USA
| |
Collapse
|
19
|
Amoateng P, Tagoe TA, Karikari TK, Kukuia KKE, Osei-Safo D, Woode E, Frenguelli BG, Kombian SB. Synedrella nodiflora Extract Depresses Excitatory Synaptic Transmission and Chemically-Induced In Vitro Seizures in the Rat Hippocampus. Front Pharmacol 2021; 12:610025. [PMID: 33762938 PMCID: PMC7982396 DOI: 10.3389/fphar.2021.610025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 01/07/2021] [Indexed: 01/14/2023] Open
Abstract
Extracts of the tropical Cinderella plant Synedrella nodiflora are used traditionally to manage convulsive conditions in the West African sub-region. This study sought to determine the neuronal basis of the effectiveness of these plant extracts to suppress seizure activity. Using the hippocampal slice preparation from rats, the ability of the extract to depress excitatory synaptic transmission and in vitro seizure activity were investigated. Bath perfusion of the hydro-ethanolic extract of Synedrella nodiflora (SNE) caused a concentration-dependent depression of evoked field excitatory postsynaptic potentials (fEPSPs) recorded extracellularly in the CA1 region of the hippocampus with maximal depression of about 80% and an estimated IC50 of 0.06 mg/ml. The SNE-induced fEPSP depression was accompanied by an increase in paired pulse facilitation. The fEPSP depression only recovered partially after 20 min washing out. The effect of SNE was not stimulus dependent as it was present even in the absence of synaptic stimulation. Furthermore, it did not show desensitization as repeat application after 10 min washout produced the same level of fEPSP depression as the first application. The SNE effect on fEPSPs was not via adenosine release as it was neither blocked nor reversed by 8-CPT, an adenosine A1 receptor antagonist. In addition, SNE depressed in vitro seizures induced by zero Mg2+ and high K+ -containing artificial cerebrospinal fluid (aCSF) in a concentration-dependent manner. The results show that SNE depresses fEPSPs and spontaneous bursting activity in hippocampal neurons that may underlie its ability to abort convulsive activity in persons with epilepsy.
Collapse
Affiliation(s)
- Patrick Amoateng
- Department of Pharmacology and Toxicology, School of Pharmacy, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Thomas A Tagoe
- Department of Physiology, UG Medical School, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Thomas K Karikari
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Kennedy K E Kukuia
- Department of Medical Pharmacology, UG Medical School, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Dorcas Osei-Safo
- Department of Chemistry, School of Physical and Mathematical Sciences, College of Basic and Applied Sciences, University of Ghana, Accra, Ghana
| | - Eric Woode
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Health and Allied Sciences, Ho, Ghana
| | - Bruno G Frenguelli
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Samuel B Kombian
- Department of Pharmacology and Therapeutics, Faculty of Pharmacy, Health Science Center, Kuwait University, Safat, Kuwait.,Department of Pharmacology and Toxicology, School of Medicine and Medical Sciences, University for Development Studies, Tamale, Ghana
| |
Collapse
|
20
|
Dzhala VI, Staley KJ. KCC2 Chloride Transport Contributes to the Termination of Ictal Epileptiform Activity. eNeuro 2021; 8:ENEURO.0208-20.2020. [PMID: 33239270 PMCID: PMC7986536 DOI: 10.1523/eneuro.0208-20.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 11/02/2020] [Accepted: 11/03/2020] [Indexed: 01/10/2023] Open
Abstract
Recurrent seizures intensely activate GABAA receptors (GABAA-Rs), which induces transient neuronal chloride ([Cl-]i) elevations and depolarizing GABA responses that contribute to the failure of inhibition that engenders further seizures and anticonvulsant resistance. The K+-Cl- cotransporter KCC2 is responsible for Cl- extrusion and restoration of [Cl-]i equilibrium (ECl) after synaptic activity, but at the cost of increased extracellular potassium which may retard K+-Cl- extrusion, depolarize neurons, and potentiate seizures. Thus, KCC2 may either diminish or facilitate seizure activity, and both proconvulsant and anticonvulsant effects of KCC2 inhibition have been reported. It is now necessary to identify the loci of these divergent responses by assaying both the electrographic effects and the ionic effects of KCC2 manipulation. We therefore determined the net effects of KCC2 transport activity on cytoplasmic chloride elevation and Cl- extrusion rates during spontaneous recurrent ictal-like epileptiform discharges (ILDs) in organotypic hippocampal slices in vitro, as well as the correlation between ionic and electrographic effects. We found that the KCC2 antagonist VU0463271 reduced Cl- extrusion rates, increased ictal [Cl-]i elevation, increased ILD duration, and induced status epilepticus (SE). In contrast, the putative KCC2 upregulator CLP257 improved chloride homeostasis and reduced the duration and frequency of ILDs in a concentration-dependent manner. Our results demonstrate that measuring both the ionic and electrographic effects of KCC2 transport clarify the impact of KCC2 modulation in specific models of epileptiform activity. Anticonvulsant effects predominate when KCC2-mediated chloride transport rather than potassium buffering is the rate-limiting step in restoring ECl and the efficacy of GABAergic inhibition during recurrent ILDs.
Collapse
Affiliation(s)
- Volodymyr I Dzhala
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114
- Harvard Medical School, Boston, MA 02114
| | - Kevin J Staley
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114
- Harvard Medical School, Boston, MA 02114
| |
Collapse
|
21
|
Intricacies of GABA A Receptor Function: The Critical Role of the β3 Subunit in Norm and Pathology. Int J Mol Sci 2021; 22:ijms22031457. [PMID: 33535681 PMCID: PMC7867123 DOI: 10.3390/ijms22031457] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 12/23/2022] Open
Abstract
Neuronal intracellular chloride ([Cl−]i) is a key determinant in γ-aminobutyric acid type A (GABA)ergic signaling. γ-Aminobutyric acid type A receptors (GABAARs) mediate both inhibitory and excitatory neurotransmission, as the passive fluxes of Cl− and HCO3− via pores can be reversed by changes in the transmembrane concentration gradient of Cl−. The cation–chloride co-transporters (CCCs) are the primary systems for maintaining [Cl−]i homeostasis. However, despite extensive electrophysiological data obtained in vitro that are supported by a wide range of molecular biological studies on the expression patterns and properties of CCCs, the presence of ontogenetic changes in [Cl−]i—along with the consequent shift in GABA reversal potential—remain a subject of debate. Recent studies showed that the β3 subunit possesses properties of the P-type ATPase that participates in the ATP-consuming movement of Cl− via the receptor. Moreover, row studies have demonstrated that the β3 subunit is a key player in GABAAR performance and in the appearance of serious neurological disorders. In this review, we discuss the properties and driving forces of CCCs and Cl−, HCO3−ATPase in the maintenance of [Cl−]i homeostasis after changes in upcoming GABAAR function. Moreover, we discuss the contribution of the β3 subunit in the manifestation of epilepsy, autism, and other syndromes.
Collapse
|
22
|
Kwon HH, Lee JS, Park H, Shin J, Yin Y, Shin N, Shin HJ, Hwang JA, Kim DW, Kang JW. Vitamin E reduces spasms caused by prenatal stress by lowering calpain expression. Epilepsy Behav 2021; 114:107609. [PMID: 33257295 DOI: 10.1016/j.yebeh.2020.107609] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 10/28/2020] [Accepted: 10/28/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND Prenatal stress increases the susceptibility of infants to seizures and is known to be associated with oxidative stress. Recent studies suggest that vitamin E has beneficial effects in various neurological diseases due to its antioxidant properties. In this study, we investigated the relationship between prenatal stress and vitamin E treatment on N-methyl-D-aspartate (NMDA)-induced spasms. METHODS We used pregnant female Sprague Dawley rats and induced prenatal stress with an injection of betamethasone on G15. They were then treated orally with 200 mg/kg vitamin E or saline twice a day from G15-G21. On postnatal day 15, NMDA was administered to trigger spasms in offspring. The total number of spasms and latency to the first spasm were recorded. We also measured oxidative stress in the medial cortex using western blot, and calpain activity, thiobarbituric acid reactive substances (TBARS), glutathione (GSH)/GSH/glutathione disulfide (GSSG), superoxide dismutase (SOD) activity, catalase activity, and nitric oxide (NO) assays. RESULTS We observed that rats treated with vitamin E while exposed to prenatal stress demonstrated reduced total number and frequency of spasms. Expression of glutamate decarboxylase 67 (GAD67) and K+/Cl- co-transporter (KCC2) were reduced after prenatal stress; this recovered in the vitamin E treated group. Further, expression of calpain 2 was decreased and various markers of oxidative stress (malondialdehyde (MDA), GSH/GSSG, SOD, catalase, and NO) were reduced in the vitamin E treated group. CONCLUSIONS Our results provide evidence that vitamin E lowers oxidative stress and decreases seizure susceptibility in rat offspring exposed to prenatal stress. Given the well-known safety profile of vitamin E, these results indicate its potential as a strategy for preventing seizures.
Collapse
Affiliation(s)
- Hyeok Hee Kwon
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, Republic of Korea; Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, Republic of Korea; Department of Pediatrics, Chungnam National University Hospital, School of Medicine, Chungnam National University, Daejeon, Republic of Korea
| | - Jin-Seok Lee
- Liver and Immunology Research Center, Oriental Medical College of Daejeon University, 22-5 Daehung-dong, Jung-gu, Daejeon 301-724, Republic of Korea
| | - Hyewon Park
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, Republic of Korea; Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, Republic of Korea
| | - Juhee Shin
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, Republic of Korea; Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, Republic of Korea
| | - Yuhua Yin
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, Republic of Korea; Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, Republic of Korea
| | - Nara Shin
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, Republic of Korea; Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, Republic of Korea
| | - Hyo Jung Shin
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, Republic of Korea; Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, Republic of Korea
| | - Jeong-Ah Hwang
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, Republic of Korea; Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, Republic of Korea
| | - Dong Woon Kim
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, Republic of Korea; Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
| | - Joon Won Kang
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, Republic of Korea; Department of Pediatrics, Chungnam National University Hospital, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
| |
Collapse
|
23
|
|
24
|
Ccny knockout mice display an enhanced susceptibility to kainic acid-induced epilepsy. Pharmacol Res 2020; 160:105100. [DOI: 10.1016/j.phrs.2020.105100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 07/23/2020] [Accepted: 07/23/2020] [Indexed: 01/30/2023]
|
25
|
Lin Y, Lei L, Ju LS, Xu N, Morey TE, Gravenstein N, Yang J, Martynyuk AE. Neonatal exposure to sevoflurane expands the window of vulnerability to adverse effects of subsequent exposure to sevoflurane and alters hippocampal morphology via decitabine-sensitive mechanisms. Neurosci Lett 2020; 735:135240. [PMID: 32650051 DOI: 10.1016/j.neulet.2020.135240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 06/09/2020] [Accepted: 07/07/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND Deficiencies in neurocognitive function have been found in late childhood or adolescence in patients who had prolonged and/or repeated early-life general anesthesia. Animal studies suggest that anesthetic-induced impairment in the neuron-specific K+-2Cl- (Kcc2) Cl- exporter expression, which regulates developmental maturation of GABA type A receptor (GABAAR) signaling from excitatory to inhibitory, may play a mediating role. We tested whether the DNA methyltransferase (DNMT) inhibitor decitabine ameliorates the anesthetic's adverse effects. METHODS Sprague-Dawley male rats were injected with vehicle or decitabine 30 min before 2.1 % sevoflurane exposure for 5 h on postnatal day 5 (P5). On P19, P20, or P21, electroencephalography-detectable seizures were measured during 1 h of sevoflurane exposure, followed by collection of the trunk blood and brain tissue samples. Other rats were evaluated for changes in hippocampal CA1 dendrite morphology and gene expressions on ≥ P120. RESULTS Rats in the vehicle plus sevoflurane group responded to sevoflurane exposure on P19, P20 or P21 with electroencephalography-detectable seizures and stress-like corticosterone secretion and had altered hippocampal dendrite morphology in adulthood. These rats had expressions of Kcc2 and Dnmt genes downregulated and upregulated, respectively, in the P19 - P21 cortex and hypothalamus and the ≥ P120 hippocampus. All measured parameters in the sevoflurane-exposed rats that were pretreated with decitabine were not different from those in the control group. CONCLUSIONS Neonatal exposure to sevoflurane sensitizes rats to adverse effects of repeated exposure to the anesthetic. The anesthetic-caused changes in the decitabine-sensitive mechanisms may play a mediating role in the developmental effects of early-life anesthesia.
Collapse
Affiliation(s)
- Yunan Lin
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States; Department of Anesthesiology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Lei Lei
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Ling-Sha Ju
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Ning Xu
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Timothy E Morey
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Nikolaus Gravenstein
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States; McKnight Brain Institute, University of Florida College of Medicine, Gainesville, FL, United States
| | - Jianjun Yang
- Department of Anesthesiology, Pain and Perioperative Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Anatoly E Martynyuk
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States; McKnight Brain Institute, University of Florida College of Medicine, Gainesville, FL, United States.
| |
Collapse
|
26
|
Murata Y, Colonnese MT. GABAergic interneurons excite neonatal hippocampus in vivo. SCIENCE ADVANCES 2020; 6:eaba1430. [PMID: 32582852 PMCID: PMC7292633 DOI: 10.1126/sciadv.aba1430] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 04/14/2020] [Indexed: 06/01/2023]
Abstract
GABAergic interneurons are proposed to be critical for early activity and synapse formation by directly exciting, rather than inhibiting, neurons in developing hippocampus and neocortex. However, the role of GABAergic neurons in the generation of neonatal network activity has not been tested in vivo, and recent studies have challenged the excitatory nature of early GABA. By locally manipulating interneuron activity in unanesthetized neonatal mice, we show that GABAergic neurons are excitatory in CA1 hippocampus at postnatal day 3 (P3) and are responsible for most of the spontaneous firing of pyramidal cells at that age. Hippocampal interneurons become inhibitory by P7, whereas visual cortex interneurons are already inhibitory by P3 and remain so throughout development. These regional and age-specific differences are the result of a change in chloride reversal potential, because direct activation of light-gated anion channels in glutamatergic neurons drives CA1 firing at P3, but silences it at P7 in CA1, and at all ages in visual cortex. This study in the intact brain reveals that GABAergic interneuron excitation is essential for network activity in neonatal hippocampus and confirms that visual cortical interneurons are inhibitory throughout early postnatal development.
Collapse
|
27
|
Martynyuk AE, Ju LS, Morey TE, Zhang JQ. Neuroendocrine, epigenetic, and intergenerational effects of general anesthetics. World J Psychiatry 2020; 10:81-94. [PMID: 32477904 PMCID: PMC7243620 DOI: 10.5498/wjp.v10.i5.81] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 03/18/2020] [Accepted: 03/26/2020] [Indexed: 02/05/2023] Open
Abstract
The progress of modern medicine would be impossible without the use of general anesthetics (GAs). Despite advancements in refining anesthesia approaches, the effects of GAs are not fully reversible upon GA withdrawal. Neurocognitive deficiencies attributed to GA exposure may persist in neonates or endure for weeks to years in the elderly. Human studies on the mechanisms of the long-term adverse effects of GAs are needed to improve the safety of general anesthesia but they are hampered not only by ethical limitations specific to human research, but also by a lack of specific biological markers that can be used in human studies to safely and objectively study such effects. The latter can primarily be attributed to an insufficient understanding of the full range of the biological effects induced by GAs and the molecular mechanisms mediating such effects even in rodents, which are far more extensively studied than any other species. Our most recent experimental findings in rodents suggest that GAs may adversely affect many more people than is currently anticipated. Specifically, we have shown that anesthesia with the commonly used GA sevoflurane induces in exposed animals not only neuroendocrine abnormalities (somatic effects), but also epigenetic reprogramming of germ cells (germ cell effects). The latter may pass the neurobehavioral effects of parental sevoflurane exposure to the offspring, who may be affected even at levels of anesthesia that are not harmful to the exposed parents. The large number of patients who require general anesthesia, the even larger number of their future unexposed offspring whose health may be affected, and a growing number of neurodevelopmental disorders of unknown etiology underscore the translational importance of investigating the intergenerational effects of GAs. In this mini review, we discuss emerging experimental findings on neuroendocrine, epigenetic, and intergenerational effects of GAs.
Collapse
Affiliation(s)
- Anatoly E Martynyuk
- Department of Anesthesiology and the McKnight Brain Institute, University of Florida College of Medicine, Gainesville, FL 32610, United States
| | - Ling-Sha Ju
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL 32610, United States
| | - Timothy E Morey
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL 32610, United States
| | - Jia-Qiang Zhang
- Department of Anesthesiology and Perioperative Medicine, Henan Provincial People’s Hospital, People's Hospital of Zhengzhou University, Zhengzhou 450003, Henan Province, China
| |
Collapse
|
28
|
Duy PQ, He M, He Z, Kahle KT. Preclinical insights into therapeutic targeting of KCC2 for disorders of neuronal hyperexcitability. Expert Opin Ther Targets 2020; 24:629-637. [PMID: 32336175 DOI: 10.1080/14728222.2020.1762174] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
INTRODUCTION Epilepsy is a common neurological disorder of neuronal hyperexcitability that begets recurrent and unprovoked seizures. The lack of a truly satisfactory pharmacotherapy for epilepsy highlights the clinical urgency for the discovery of new drug targets. To that end, targeting the electroneutral K+/Cl- cotransporter KCC2 has emerged as a novel therapeutic strategy for the treatment of epilepsy. AREAS COVERED We summarize the roles of KCC2 in the maintenance of synaptic inhibition and the evidence linking KCC2 dysfunction to epileptogenesis. We also discuss preclinical proof-of-principle studies that demonstrate that augmentation of KCC2 function can reduce seizure activity. Moreover, potential strategies to modulate KCC2 activity for therapeutic benefit are highlighted. EXPERT OPINION Although KCC2 is a promising drug target, questions remain before clinical translation. It is unclear whether increasing KCC2 activity can reverse epileptogenesis, the ultimate curative goal for epilepsy therapy that extends beyond seizure reduction. Furthermore, the potential adverse effects associated with increased KCC2 function have not been studied. Continued investigations into the neurobiology of KCC2 will help to translate promising preclinical insights into viable therapeutic avenues that leverage fundamental properties of KCC2 to treat medically intractable epilepsy and other disorders of failed synaptic inhibition with attendant neuronal hyperexcitability.
Collapse
Affiliation(s)
- Phan Q Duy
- Department of Neurosurgery, Yale University School of Medicine , New Haven, CT, USA.,Medical Scientist Training Program, Yale University School of Medicine , New Haven, CT, USA
| | - Miao He
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, and Department of Neurology, Harvard Medical School , Boston, MA, USA
| | - Zhigang He
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, and Department of Neurology, Harvard Medical School , Boston, MA, USA
| | - Kristopher T Kahle
- Department of Neurosurgery, Yale University School of Medicine , New Haven, CT, USA.,Department of Genetics, Yale University School of Medicine , New Haven, CT, USA.,Departments of Pediatrics and Cellular & Molecular Physiology, Yale University School of Medicine , New Haven, CT, USA.,Yale-Rockefeller NIH Centers for Mendelian Genomics, Yale University , New Haven, CT, USA.,Yale Stem Cell Center, Yale School of Medicine , New Haven, CT, USA
| |
Collapse
|
29
|
De Araujo Furtado M, Aroniadou-Anderjaska V, Figueiredo TH, Apland JP, Braga MFM. Electroencephalographic analysis in soman-exposed 21-day-old rats and the effects of midazolam or LY293558 with caramiphen. Ann N Y Acad Sci 2020; 1479:122-133. [PMID: 32237259 DOI: 10.1111/nyas.14331] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 02/25/2020] [Accepted: 02/27/2020] [Indexed: 12/19/2022]
Abstract
Acute nerve agent exposure induces status epilepticus (SE), which can cause brain damage or death. Research aiming at developing effective therapies for controlling nerve agent-induced SE is commonly performed in adult rats. The characteristics of nerve agent-induced SE in young rats are less clear; relevant knowledge is necessary for developing effective pediatric therapies. Here, we have used electroencephalographic (EEG) recordings and analysis to study seizures in postnatal day 21 rats exposed to 1.2 × LD50 of soman, and compared the antiseizure efficacy of midazolam (MDZ)-currently considered by the Food and Drug Administration to replace diazepam for treating SE in victims of nerve agent exposure-with that of LY293558, an AMPA/GluK1 receptor antagonist, administered in combination with caramiphen, an antimuscarinic with N-methyl-d-aspartate receptor antagonistic properties. Prolonged SE developed in 80% of the rats and was reflected in behavioral seizures/convulsions. Both MDZ and LY293558 + caramiphen stopped the SE induced by soman, but there was a significant recurrence of seizures within 24 h postexposure only in the MDZ-treated group, as revealed in the raw EEG data and their representation in the frequency domain using a fast Fourier transform and in spectral analysis over 24 hours. In contrast to the high efficacy of LY293558 + caramiphen, MDZ is not an effective treatment for SE induced by soman in young animals.
Collapse
Affiliation(s)
- Marcio De Araujo Furtado
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Vassiliki Aroniadou-Anderjaska
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University of the Health Sciences, Bethesda, Maryland.,Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Taiza H Figueiredo
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - James P Apland
- Neurotoxicology Branch, the United States Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland
| | - Maria F M Braga
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University of the Health Sciences, Bethesda, Maryland.,Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| |
Collapse
|
30
|
Abstract
BACKGROUND Sevoflurane administered to neonatal rats induces neurobehavioral abnormalities and epigenetic reprogramming of their germ cells; the latter can pass adverse effects of sevoflurane to future offspring. As germ cells are susceptible to reprogramming by environmental factors across the lifespan, the authors hypothesized that sevoflurane administered to adult rats could induce neurobehavioral abnormalities in future offspring, but not in the exposed rats themselves. METHODS Sprague-Dawley rats were anesthetized with 2.1% sevoflurane for 3 h every other day between postnatal days 56 and 60. Twenty-five days later, exposed rats and nonexposed controls were mated to produce offspring. RESULTS Adult male but not female offspring of exposed parents of either sex exhibited deficiencies in elevated plus maze (mean ± SD, offspring of both exposed parents vs. offspring of control parents, 35 ± 12 vs. 15 ± 15 s, P < 0.001) and prepulse inhibition of acoustic startle (offspring of both exposed parents vs. offspring of control parents, 46.504 ± 13.448 vs. 25.838 ± 22.866%, P = 0.009), and increased methylation and reduced expression of the potassium ion-chloride ion cotransporter KCC2 gene (Kcc2) in the hypothalamus. Kcc2 was also hypermethylated in sperm and ovary of the exposed rats. Surprisingly, exposed male rats also exhibited long-term abnormalities in functioning of the hypothalamic-pituitary-gonadal and -adrenal axes, reduced expression of hypothalamic and hippocampal Kcc2, and deficiencies in elevated plus maze (sevoflurane vs. control, 40 ± 24 vs. 25 ± 12 s, P = 0.038) and prepulse inhibition of startle (sevoflurane vs. control, 39.905 ± 21.507 vs. 29.193 ± 24.263%, P < 0.050). CONCLUSIONS Adult sevoflurane exposure affects brain development in male offspring by epigenetically reprogramming both parental germ cells, while it induces neuroendocrine and behavioral abnormalities only in exposed males. Sex steroids may be required for mediation of the adverse effects of adult sevoflurane in exposed males.
Collapse
|
31
|
Li N, Xu N, Lin Y, Lei L, Ju LS, Morey TE, Gravenstein N, Zhang J, Martynyuk AE. Roles of Testosterone and Estradiol in Mediation of Acute Neuroendocrine and Electroencephalographic Effects of Sevoflurane During the Sensitive Period in Rats. Front Endocrinol (Lausanne) 2020; 11:545973. [PMID: 33101193 PMCID: PMC7556268 DOI: 10.3389/fendo.2020.545973] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 09/10/2020] [Indexed: 01/14/2023] Open
Abstract
Testosterone (T), predominantly acting through its derivative 17β-estradiol (E2), regulates the brain's sexual differentiation in rodents during the perinatal sensitive period, which mirrors the window of vulnerability to the adverse effects of general anesthetics. The mechanisms of anesthesia's adverse effects are poorly understood. We investigated whether sevoflurane alters T and E2 levels and whether they contribute to sevoflurane's acute adverse effects in postnatal day 5 Sprague-Dawley rats. The rats underwent electroencephalography recordings for 2 h of baseline activity or for 1 h before and another hour during 2.1% sevoflurane exposure, followed by collection of trunk blood and brain tissue. Pharmacological agents, including the GABA type A receptor inhibitor bicuculline and the aromatase inhibitor formestane, were administered 30 min before sevoflurane anesthesia. Sevoflurane increased serum T levels in males only. All other effects of sevoflurane were similar in both sexes, including increases in serum levels of E2, hypothalamic mRNA levels of aromatase, estrogen receptor α (Erα) [not estrogen receptor β (Erβ)], Na+-K+-Cl- cotransporter (Nkcc1)/K+-Cl- cotransporter (Kcc2) mRNA ratio, electroencephalography-detectable seizures, and stress-like corticosterone secretion. Bicuculline and formestane alleviated these effects, except the T level increases. The ERα antagonist MPP, but not the ERβ antagonist PHTPP, reduced electroencephalography-detectable seizures and normalized the Nkcc1/Kcc2 mRNA ratio. Collectively, sevoflurane exacerbates levels of T in males and E2 in both sexes during the period of their organizational effects in rodents. Sevoflurane acts through GABAAR-mediated, systemic T-independent elevation of E2 to cause electroencephalography-detectable seizures, stress-like corticosterone secretion, and changes in the expression of genes critical for brain development.
Collapse
Affiliation(s)
- Ningtao Li
- Department of Anesthesiology and Perioperative Medicine, Henan Provincial People’s Hospital, People’s Hospital of Zhengzhou University, Zhengzhou, China
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Ning Xu
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Yunan Lin
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Lei Lei
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Ling-Sha Ju
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Timothy E. Morey
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Nikolaus Gravenstein
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Jiaqiang Zhang
- Department of Anesthesiology and Perioperative Medicine, Henan Provincial People’s Hospital, People’s Hospital of Zhengzhou University, Zhengzhou, China
- *Correspondence: Jiaqiang Zhang, ; Anatoly E. Martynyuk,
| | - Anatoly E. Martynyuk
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
- McKnight Brain Institute, University of Florida College of Medicine, Gainesville, FL, United States
- *Correspondence: Jiaqiang Zhang, ; Anatoly E. Martynyuk,
| |
Collapse
|
32
|
Synaptic Plasticity Shapes Brain Connectivity: Implications for Network Topology. Int J Mol Sci 2019; 20:ijms20246193. [PMID: 31817968 PMCID: PMC6940892 DOI: 10.3390/ijms20246193] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/02/2019] [Accepted: 12/06/2019] [Indexed: 12/13/2022] Open
Abstract
Studies of brain network connectivity improved understanding on brain changes and adaptation in response to different pathologies. Synaptic plasticity, the ability of neurons to modify their connections, is involved in brain network remodeling following different types of brain damage (e.g., vascular, neurodegenerative, inflammatory). Although synaptic plasticity mechanisms have been extensively elucidated, how neural plasticity can shape network organization is far from being completely understood. Similarities existing between synaptic plasticity and principles governing brain network organization could be helpful to define brain network properties and reorganization profiles after damage. In this review, we discuss how different forms of synaptic plasticity, including homeostatic and anti-homeostatic mechanisms, could be directly involved in generating specific brain network characteristics. We propose that long-term potentiation could represent the neurophysiological basis for the formation of highly connected nodes (hubs). Conversely, homeostatic plasticity may contribute to stabilize network activity preventing poor and excessive connectivity in the peripheral nodes. In addition, synaptic plasticity dysfunction may drive brain network disruption in neuropsychiatric conditions such as Alzheimer's disease and schizophrenia. Optimal network architecture, characterized by efficient information processing and resilience, and reorganization after damage strictly depend on the balance between these forms of plasticity.
Collapse
|
33
|
Ghafouri S, Fathollahi Y, Semnanian S, Shojaei A, Asgari A, Ebrahim Amini A, Mirnajafi-Zadeh J. Deep brain stimulation restores the glutamatergic and GABAergic synaptic transmission and plasticity to normal levels in kindled rats. PLoS One 2019; 14:e0224834. [PMID: 31697763 PMCID: PMC6837391 DOI: 10.1371/journal.pone.0224834] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Accepted: 10/22/2019] [Indexed: 01/13/2023] Open
Abstract
Background The precise effect of low frequency stimulation (LFS) as a newly postulated, anticonvulsant therapeutic approach on seizure-induced changes in synaptic transmission has not been completely determined. Hypothesis In this study, the LFS effect on impaired, synaptic plasticity in kindled rats was investigated. Methods Hippocampal kindled rats received LFS (4 trials consisting of one train of 200 monophasic square waves, 0.1 ms pulse duration, 1 Hz) on four occasions. LTP induction was evaluated using whole-cell recordings of evoked excitatory and inhibitory post-synaptic potentials (EPSPs and IPSPs respectively) in CA1 neurons in hippocampal slices. In addition, the hippocampal excitatory and inhibitory post-synaptic currents (EPSCs and IPSCs), and the gene expression of NR2A, GluR2 and γ2 were evaluated. Results LTP induction was attenuated in excitatory and inhibitory synapses in hippocampal slices of kindled rats. When LFS was applied in kindled animals, LTP was induced in EPSPs and IPSPs. Moreover, LFS increased and decreased the threshold intensities of EPSCs and IPSCs respectively. In kindled animals, NR2A gene expression increased, while γ2 gene expression decreased. GluR2 gene expression did not significantly change. Applying LFS in kindled animals mitigated these changes: No significant differences were observed in NR2A, γ2 and GluR2 gene expression in the kindled+LFS and control groups. Conclusion The application of LFS in kindled animals restored LTP induction in both EPSPs and IPSPs, and returned the threshold intensity for induction of EPSCs, IPSCs and gene expression to similar levels as controls.
Collapse
Affiliation(s)
- Samireh Ghafouri
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Yaghoub Fathollahi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Saeed Semnanian
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Amir Shojaei
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Azam Asgari
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
- Département de Neurosciences, Université de Montréal, Montréal, Canada
| | - Azin Ebrahim Amini
- Department of Biomaterial and Biomedical Engineering (IBBME), Faculty of applied sciences, University of Toronto, Toronto, Canada
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
- Institute for Brain Sciences and Cognition, Tarbiat Modares University, Tehran, Iran
- * E-mail:
| |
Collapse
|
34
|
Sharopov S, Winkler P, Uehara R, Lombardi A, Halbhuber L, Okabe A, Luhmann HJ, Kilb W. Allopregnanolone augments epileptiform activity of an in-vitro mouse hippocampal preparation in the first postnatal week. Epilepsy Res 2019; 157:106196. [PMID: 31499340 DOI: 10.1016/j.eplepsyres.2019.106196] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 08/21/2019] [Accepted: 08/28/2019] [Indexed: 02/06/2023]
Abstract
In the immature brain the neurotransmitter γ-amino butyric acid (GABA) mediates a membrane depolarization and can contribute to both, inhibition and excitation. Therefore the consequences of a positive modulation of GABA(A) receptors by neurosteroids on epileptiform activity are hard to predict. In order to analyze whether neurosteroids attenuate or exaggerate epileptiform activity in the immature brain, we investigated the effect of the neurosteroid allopregnanolone on epileptiform activity in an in-toto hippocampus preparation of early postnatal mice (postnatal days 4-7) using field potential recordings. These in-vitro experiments revealed that 0.5 μmol/L allopregnanolone had no effect on ictal-like epileptiform activity, but increased the occurrence of interictal epileptiform events. The allopregnanolone-induced enhancement of interictal epileptiform activity could be blocked by a selective inhibition of synaptic GABAA receptors. In contrast, allopregnanolone had no effect on interictal epileptiform activity upon enhanced extrasynaptic GABAergic activity. Patch-clamp experiments demonstrated that allopregnanolone prolonged the decay of GABAergic postsynaptic currents, but had no effect on tonic GABAergic currents. We conclude from these results that allopregnanolone can enhance excitability in the immature hippocampus viaprolonged synaptic GABAergic currents. This potential effect of neurosteroids on brain excitability should be considered if they are applied as anticonvulsants to premature or early postnatal babies.
Collapse
Affiliation(s)
- Salim Sharopov
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55120, Mainz, Germany
| | - Paula Winkler
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55120, Mainz, Germany
| | - Rie Uehara
- Department of Molecular Anatomy, School of Medicine, University of the Ryukyus, 207 Uehara, Nishihara, Okinawa, 903-0215, Japan
| | - Aniello Lombardi
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55120, Mainz, Germany
| | - Lisa Halbhuber
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55120, Mainz, Germany
| | - Akihito Okabe
- Department of Molecular Anatomy, School of Medicine, University of the Ryukyus, 207 Uehara, Nishihara, Okinawa, 903-0215, Japan; Department of Nutritional Sciences, Faculty of Health and Welfare, Seinan Jo Gakuin University, 1-3-5 Ibori, Kokurakita-ku, Kitakyushu, Fukuoka, 803-0835, Japan
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55120, Mainz, Germany
| | - Werner Kilb
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55120, Mainz, Germany.
| |
Collapse
|
35
|
Carrasco M, Stafstrom CE. How Early Can a Seizure Happen? Pathophysiological Considerations of Extremely Premature Infant Brain Development. Dev Neurosci 2019; 40:417-436. [PMID: 30947192 DOI: 10.1159/000497471] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 02/04/2019] [Indexed: 11/19/2022] Open
Abstract
Seizures in neonates represent a neurologic emergency requiring prompt recognition, determination of etiology, and treatment. Yet, the definition and identification of neonatal seizures remain challenging and controversial, in part due to the unique physiology of brain development at this life stage. These issues are compounded when considering seizures in premature infants, in whom the complexities of brain development may engender different clinical and electrographic seizure features at different points in neuronal maturation. In extremely premature infants (< 28 weeks gestational age), seizure pathophysiology has not been explored in detail. This review discusses the physiological and structural development of the brain in this developmental window, focusing on factors that may lead to seizures and their consequences at this early time point. We hypothesize that the clinical and electrographic phenomenology of seizures in extremely preterm infants reflects the specific pathophysiology of brain development in that age window.
Collapse
Affiliation(s)
- Melisa Carrasco
- Division of Pediatric Neurology, Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Carl E Stafstrom
- Division of Pediatric Neurology, Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA,
| |
Collapse
|
36
|
Murata Y, Colonnese MT. Thalamic inhibitory circuits and network activity development. Brain Res 2019; 1706:13-23. [PMID: 30366019 PMCID: PMC6363901 DOI: 10.1016/j.brainres.2018.10.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 09/30/2018] [Accepted: 10/22/2018] [Indexed: 02/06/2023]
Abstract
Inhibitory circuits in thalamus and cortex shape the major activity patterns observed by electroencephalogram (EEG) in the adult brain. Their delayed maturation and circuit integration, relative to excitatory neurons, suggest inhibitory neuronal development could be responsible for the onset of mature thalamocortical activity. Indeed, the immature brain lacks many inhibition-dependent activity patterns, such as slow-waves, delta oscillations and sleep-spindles, and instead expresses other unique oscillatory activities in multiple species including humans. Thalamus contributes significantly to the generation of these early oscillations. Compared to the abundance of studies on the development of inhibition in cortex, however, the maturation of thalamic inhibition is poorly understood. Here we review developmental changes in the neuronal and circuit properties of the thalamic relay and its interconnected inhibitory thalamic reticular nucleus (TRN) both in vitro and in vivo, and discuss their potential contribution to early network activity and its maturation. While much is unknown, we argue that weak inhibitory function in the developing thalamus allows for amplification of thalamocortical activity that supports the generation of early oscillations. The available evidence suggests that the developmental acquisition of critical thalamic oscillations such as slow-waves and sleep-spindles is driven by maturation of the TRN. Further studies to elucidate thalamic GABAergic circuit formation in relation to thalamocortical network function would help us better understand normal as well as pathological brain development.
Collapse
Affiliation(s)
- Yasunobu Murata
- Department of Pharmacology and Physiology, and Institute for Neuroscience, George Washington University, 2300 Eye Street NW, Washington, DC 20037, USA.
| | - Matthew T Colonnese
- Department of Pharmacology and Physiology, and Institute for Neuroscience, George Washington University, 2300 Eye Street NW, Washington, DC 20037, USA.
| |
Collapse
|
37
|
Aroniadou-Anderjaska V, Figueiredo TH, Apland JP, Braga MF. Targeting the glutamatergic system to counteract organophosphate poisoning: A novel therapeutic strategy. Neurobiol Dis 2019; 133:104406. [PMID: 30798006 DOI: 10.1016/j.nbd.2019.02.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 01/23/2019] [Accepted: 02/20/2019] [Indexed: 12/15/2022] Open
Abstract
One of the devastating effects of acute exposure to organophosphates, like nerve agents, is the induction of severe and prolonged status epilepticus (SE), which can cause death, or brain damage if death is prevented. Seizures after exposure are initiated by muscarinic receptor hyperstimulation-after inhibition of acetylcholinesterase by the organophosphorus agent and subsequent elevation of acetylcholine-but they are reinforced and sustained by glutamatergic hyperexcitation, which is the primary cause of brain damage. Diazepam is the FDA-approved anticonvulsant for the treatment of nerve agent-induced SE, and its replacement by midazolam is currently under consideration. However, clinical data derived from the treatment of SE of any etiology, as well as studies on the control of nerve agent-induced SE in animal models, have indicated that diazepam and midazolam control seizures only temporarily, their antiseizure efficacy is reduced as the latency of treatment from the onset of SE increases, and their neuroprotective efficacy is limited or absent. Here, we review data on the discovery of a novel anticonvulsant and neuroprotectant, LY293558, an AMPA/GluK1 receptor antagonist. Treatment of soman-exposed immature, young-adult, and aged rats with LY293558, terminates SE with limited recurrence of seizures, significantly protects from brain damage, and prevents long-term behavioral deficits, even when LY293558 is administered 1 h post-exposure. More beneficial effects and complete neuroprotection is obtained when LY293558 administration is combined with caramiphen, which antagonizes NMDA receptors. Further efficacy studies may bring the LY293558 + caramiphen combination therapy on the pathway to approval for human use.
Collapse
Affiliation(s)
- Vassiliki Aroniadou-Anderjaska
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States of America; Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States of America.
| | - Taiza H Figueiredo
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States of America.
| | - James P Apland
- Neuroscience Program, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010, United States of America.
| | - Maria F Braga
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States of America; Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States of America.
| |
Collapse
|
38
|
Shao LR, Habela CW, Stafstrom CE. Pediatric Epilepsy Mechanisms: Expanding the Paradigm of Excitation/Inhibition Imbalance. CHILDREN-BASEL 2019; 6:children6020023. [PMID: 30764523 PMCID: PMC6406372 DOI: 10.3390/children6020023] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 01/31/2019] [Accepted: 01/31/2019] [Indexed: 02/07/2023]
Abstract
Mechanisms underlying seizures and epilepsy have traditionally been considered to involve abnormalities of ion channels or synaptic function. Those considerations gave rise to the excitation/inhibition (E/I) imbalance theory, whereby increased excitation, decreased inhibition, or both favor a hyperexcitable state and an increased propensity for seizure generation and epileptogenesis. Several recent findings warrant reconsideration and expansion of the E/I hypothesis: novel genetic mutations have been identified that do not overtly affect E/I balance; neurotransmitters may exert paradoxical effects, especially during development; anti-seizure medications do not necessarily work by decreasing excitation or increasing inhibition; and metabolic factors participate in the regulation of neuronal and network excitability. These novel conceptual and experimental advances mandate expansion of the E/I paradigm, with the expectation that new and exciting therapies will emerge from this broadened understanding of how seizures and epilepsy arise and progress.
Collapse
Affiliation(s)
- Li-Rong Shao
- Division of Pediatric Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
| | - Christa W Habela
- Division of Pediatric Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
| | - Carl E Stafstrom
- Division of Pediatric Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
| |
Collapse
|
39
|
Spoljaric I, Spoljaric A, Mavrovic M, Seja P, Puskarjov M, Kaila K. KCC2-Mediated Cl - Extrusion Modulates Spontaneous Hippocampal Network Events in Perinatal Rats and Mice. Cell Rep 2019; 26:1073-1081.e3. [PMID: 30699338 PMCID: PMC6352714 DOI: 10.1016/j.celrep.2019.01.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 11/30/2018] [Accepted: 01/02/2019] [Indexed: 01/22/2023] Open
Abstract
It is generally thought that hippocampal neurons of perinatal rats and mice lack transport-functional K-Cl cotransporter KCC2, and that Cl- regulation is dominated by Cl- uptake via the Na-K-2Cl cotransporter NKCC1. Here, we demonstrate a robust enhancement of spontaneous hippocampal network events (giant depolarizing potentials [GDPs]) by the KCC2 inhibitor VU0463271 in neonatal rats and late-gestation, wild-type mouse embryos, but not in their KCC2-null littermates. VU0463271 increased the depolarizing GABAergic synaptic drive onto neonatal CA3 pyramidal neurons, increasing their spiking probability and synchrony during the rising phase of a GDP. Our data indicate that Cl- extrusion by KCC2 is involved in modulation of GDPs already at their developmental onset during the perinatal period in mice and rats.
Collapse
Affiliation(s)
- Inkeri Spoljaric
- Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences and Neuroscience Center (HiLIFE), University of Helsinki, 00014 Helsinki, Finland
| | - Albert Spoljaric
- Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences and Neuroscience Center (HiLIFE), University of Helsinki, 00014 Helsinki, Finland
| | - Martina Mavrovic
- Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences and Neuroscience Center (HiLIFE), University of Helsinki, 00014 Helsinki, Finland
| | - Patricia Seja
- Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences and Neuroscience Center (HiLIFE), University of Helsinki, 00014 Helsinki, Finland
| | - Martin Puskarjov
- Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences and Neuroscience Center (HiLIFE), University of Helsinki, 00014 Helsinki, Finland
| | - Kai Kaila
- Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences and Neuroscience Center (HiLIFE), University of Helsinki, 00014 Helsinki, Finland.
| |
Collapse
|
40
|
Winkler P, Luhmann HJ, Kilb W. Taurine potentiates the anticonvulsive effect of the GABA A agonist muscimol and pentobarbital in the immature mouse hippocampus. Epilepsia 2019; 60:464-474. [PMID: 30682212 DOI: 10.1111/epi.14651] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 12/24/2018] [Accepted: 12/29/2018] [Indexed: 01/05/2023]
Abstract
OBJECTIVE The high incidence of epileptic seizures in neonates and their frequent refractoriness to pharmacologic therapies require identification of new therapeutical options. Therefore, we investigated whether the modulatory effect of taurine on γ-aminobutyric acid (GABA)A receptors can enhance the anticonvulsive potential of the GABAA receptor agonist muscimol and of the barbiturate pentobarbital. METHODS We performed field potential recordings in in toto hippocampus preparations of immature (postnatal days 4-7) C57Bl/6 mouse pups. Spontaneous epileptiform activity was induced by the continuous presence of the potassium channel blocker 4-aminopyridine and the glycinergic antagonist strychnine in Mg2+ -free solutions. RESULTS Bath application of 0.1 μmol/L muscimol increases the occurrence of recurrent epileptiform discharges, whereas they are significantly attenuated in a dose-dependent manner by muscimol in concentrations between 0.5 and 5 μmol/L. Taurine at concentrations between 0.1 and 0.5 mmol/L induces a proconvulsive effect, but upon coapplication, it significantly augments the anticonvulsive effect of moderate muscimol doses (0.5-1 μmol/L). In addition, the anticonvulsive effect of 100 and 200 μmol/L pentobarbital is increased significantly in the presence of 0.5 μmol/L taurine. SIGNIFICANCE These observations demonstrate that taurine can indeed enhance the anticonvulsive effects of muscimol and pentobarbital, suggesting that taurine may act as a positive modulator on GABAA receptors. Thus, interfering with the modulatory taurine binding site of GABAA receptors or the interstitial taurine concentration may provide new therapeutical options for anticonvulsive therapies in neonates.
Collapse
Affiliation(s)
- Paula Winkler
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Werner Kilb
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| |
Collapse
|
41
|
Costine-Bartell BA, McGuone D, Price G, Crawford E, Keeley KL, Munoz-Pareja J, Dodge CP, Staley K, Duhaime AC. Development of a Model of Hemispheric Hypodensity ("Big Black Brain"). J Neurotrauma 2018; 36:815-833. [PMID: 30039743 PMCID: PMC6387571 DOI: 10.1089/neu.2018.5736] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Subdural hematoma (SDH) is the most common finding after abusive head trauma (AHT). Hemispheric hypodensity (HH) is a radiological indicator of severe brain damage that encompasses multiple vascular territories, and may develop in the hemisphere(s) underlying the SDH. In some instances where the SDH is predominantly unilateral, the widespread damage is unilateral underlying the SDH. To date, no animal model has successfully replicated this pattern of injury. We combined escalating severities of the injuries and insults commonly associated with HH including SDH, impact, mass effect, seizures, apnea, and hypoventilation to create an experimental model of HH in piglets aged 1 week (comparable to human infants) to 1 month (comparable to human toddlers). Unilateral HH evolved over 24 h when kainic acid was applied ipsilateral to the SDH to induce seizures. Pathological examination revealed a hypoxic-ischemic injury-type pattern with vasogenic edema through much of the cortical ribbon with relative sparing of deep gray matter. The percentage of the hemisphere that was damaged was greater on the ipsilateral versus contralateral side and was positively correlated with SDH area and estimated seizure duration. Further studies are needed to parse out the pathophysiology of this injury and to determine if multiple injuries and insults act synergistically to induce a metabolic mismatch or if the mechanism of trauma induces severe seizures that drive this distinctive pattern of injury.
Collapse
Affiliation(s)
- Beth A Costine-Bartell
- 1 Department of Neurosurgery, Massachusetts General Hospital , Boston, Massachusetts.,2 Department of Neurosurgery, Harvard Medical School , Boston, Massachusetts
| | - Declan McGuone
- 3 Department of Pathology, Yale School of Medicine , New Haven, Connecticut
| | - George Price
- 1 Department of Neurosurgery, Massachusetts General Hospital , Boston, Massachusetts
| | - Eleanor Crawford
- 1 Department of Neurosurgery, Massachusetts General Hospital , Boston, Massachusetts
| | - Kristen L Keeley
- 1 Department of Neurosurgery, Massachusetts General Hospital , Boston, Massachusetts
| | - Jennifer Munoz-Pareja
- 4 Department of Pediatrics, University of Florida Health Shands Children's Hospital, University of Florida College of Medicine , Gainesville, Florida
| | - Carter P Dodge
- 5 Department of Anesthesiology, Children's Hospital at Dartmouth , Dartmouth Medical School, Lebanon , New Hampshire
| | - Kevin Staley
- 6 Departments of Neurology, Massachusetts General Hospital and Harvard Medical School , Boston, Massachusetts
| | - Ann-Christine Duhaime
- 1 Department of Neurosurgery, Massachusetts General Hospital , Boston, Massachusetts.,2 Department of Neurosurgery, Harvard Medical School , Boston, Massachusetts
| |
Collapse
|
42
|
Yang J, Ju L, Yang C, Xue J, Setlow B, Morey TE, Gravenstein N, Seubert CN, Vasilopoulos T, Martynyuk AE. Effects of combined brief etomidate anesthesia and postnatal stress on amygdala expression of Cl - cotransporters and corticotropin-releasing hormone and alcohol intake in adult rats. Neurosci Lett 2018; 685:83-89. [PMID: 30125644 DOI: 10.1016/j.neulet.2018.08.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/09/2018] [Accepted: 08/16/2018] [Indexed: 01/18/2023]
Abstract
Early life stressors, including general anesthesia, can have adverse effects on adult neural and behavioral outcomes, such as disruptions in inhibitory signaling, stress responsivity and increased risk of psychiatric disorders. Here we used a rat model to determine the effects of combined exposure to etomidate (ET) neonatal anesthesia and maternal separation on adult amygdala expression of genes for corticotropin-releasing hormone (Crh) and the chloride co-transporters Nkcc1 and Kcc2, as well as ethanol intake. Male and female Sprague-Dawley rats were subjected to 2 h of ET anesthesia on postnatal days (P) 4, 5, or 6 followed by maternal separation for 3 h on P10 (ET + SEP). During the P91-P120 period rats had daily 2 h access to three 0.05% saccharin solutions containing 0%, 5%, or 10% ethanol, followed by gene expression analyses. The ET + SEP group had increased Crh mRNA levels and Nkcc1/Kcc2 mRNA ratios in the amygdala, with greater increases in Nkcc1/Kcc2 mRNA ratios in males. A moderate increase in 5% ethanol intake was evident in the ET + SEP males, but not females, after calculation of the ratio of alcohol intake between the last week and first week of exposure. In contrast, control males tended to decrease alcohol consumption during the same period. A brief exposure to ET combined with a subsequent episode of stress early in life induced significant alterations in expression of amygdala Crh, Nkcc1 and Kcc2 with greater changes in the Cl- transporter expression in males. The possibility of increased alcohol intake in the exposed males requires further confirmation using different alcohol intake paradigms.
Collapse
Affiliation(s)
- Jiaojiao Yang
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Lingsha Ju
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Chunyao Yang
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Jinhu Xue
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Barry Setlow
- The McKnight Brain Institute, University of Florida College of Medicine, Gainesville, FL, United States; Department of Psychiatry, University of Florida College of Medicine, Gainesville, FL, United States
| | - Timothy E Morey
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Nikolaus Gravenstein
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States; The McKnight Brain Institute, University of Florida College of Medicine, Gainesville, FL, United States
| | - Christoph N Seubert
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Terrie Vasilopoulos
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Anatoly E Martynyuk
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States; The McKnight Brain Institute, University of Florida College of Medicine, Gainesville, FL, United States.
| |
Collapse
|
43
|
Jiang XM, Wang WP, Liu ZH, Yin HJ, Ma H, Feng N, Wang L, Huang HH, Wang XL. 2-(4-methyl-thiazol-5-yl) ethyl nitrate maleate-potentiated GABA A receptor response in hippocampal neurons. CNS Neurosci Ther 2018; 24:1231-1240. [PMID: 30039924 DOI: 10.1111/cns.13033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 06/15/2018] [Accepted: 06/25/2018] [Indexed: 12/31/2022] Open
Abstract
AIMS 2-(4-methyl-thiazol-5-yl) ethyl nitrate maleate (NMZM), a derivative of clomethiazole (CMZ), had been investigated for the treatment of Alzheimer's disease (AD). The beneficial effects of NMZM in AD included reversing cognitive deficit, improving learning and memory as well as neuroprotection. The pharmacological effects of NMZM on GABAA receptors were reported previously; however, the mechanisms were unclear and were explored therefore. RESULTS In this study, we demonstrated that NMZM improved learning and memory by alleviating scopolamine-induced long-term potentiation (LTP) suppression in the dentate gyrus of rats, indicating that NMZM had protective effects against scopolamine-induced depression of LTP. Next, we investigated the action of NMZM on GABAA receptors in hippocampal neurons and the binding site of NMZM on GABAA receptors. NMZM directly activated GABAA receptors in hippocampal neurons in a weak manner. However, NMZM could potentiate the response of GABAA receptors to GABA and NMZM positively modulated GABAA receptors with an EC50 value of 465 μmol/L at 3 μmol/L GABA while this potentiation at low concentration of GABA (1, 3 μmol/L) was more significant than that at high concentration (10, 30 μmol/L). In addition, NMZM could enhance GABA currents after using diazepam and pentobarbital, the positive modulators of GABAA receptors. NMZM could not affect the etomidate-potentiated GABAA current. It suggested that the binding site of NMZM on GABAA receptors is the same as etomidate. CONCLUSIONS These results provided support for the neuroprotective effect of NMZM, which was partly dependent on the potentiation of GABAA receptors. The etomidate binding site might be a new target for neuronal protection and for drug development.
Collapse
Affiliation(s)
- Xiao-Mei Jiang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of MateriaMedica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Wei-Ping Wang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of MateriaMedica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Zhi-Hui Liu
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of MateriaMedica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Hua-Jing Yin
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of MateriaMedica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Hao Ma
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of MateriaMedica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Nan Feng
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of MateriaMedica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Ling Wang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of MateriaMedica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Hai-Hong Huang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of MateriaMedica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xiao-Liang Wang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of MateriaMedica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| |
Collapse
|
44
|
Arzimanoglou A, D'Cruz O, Nordli D, Shinnar S, Holmes GL. A Review of the New Antiepileptic Drugs for Focal-Onset Seizures in Pediatrics: Role of Extrapolation. Paediatr Drugs 2018; 20:249-264. [PMID: 29616471 DOI: 10.1007/s40272-018-0286-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Most antiepileptic drugs (AEDs) receive regulatory approval for children years after the drug is available in adults, encouraging off-label use of the drug in children and hindering attempts to obtain quality pediatric data in controlled trials. Extrapolating adult efficacy data to pediatrics can reduce the time between approval in adults and that in children. To extrapolate efficacy from adults to children, several assumptions must be supported, such as (1) a similar disease progression and response to interventions in adults and children, and (2) similar exposure response in adults and children. The Pediatric Epilepsy Academic Consortium for Extrapolation (PEACE) addressed these assumptions in focal-onset seizures (FOS), the most common seizure type in both adults and children. PEACE reviewed the biological and clinical evidence that supported the assumptions that children with FOS have a similar disease progression and response to intervention as adults with FOS. After age 2 years, the pathophysiological underpinnings of FOS and the biological milieu in which seizures are initiated and propagated in children, seizure semiology, electroencephalographic features, etiology and AED response to FOS in children are similar to those in adults with FOS. PEACE concluded that extrapolation of efficacy data in adults to pediatrics in FOS is supported by strong scientific and clinical evidence. However, safety and pharmacokinetic (PK) data cannot be extrapolated from adults to children. Based on extrapolation, eslicarbazepine is now approved for children with FOS, down to age 4 years. Perampanel, lacosamide and brivaracetam are now undergoing PK and safety studies for the purposes of extrapolation down to age 2 or 4 years. When done in conjunction with PK and safety investigations in children, extrapolation of adult data from adults to children can reduce the time delay between approval of effective and safe AEDs in adults and approval in children.
Collapse
Affiliation(s)
- Alexis Arzimanoglou
- Department of Clinical Epileptology, Sleep Disorders and Functional Pediatric Neurology, University Hospitals of Lyon (HCL), Lyon, France.,Sección Epilepsia, Sueño y Neurofisiología, Servicio Neurología, Hospital Sant Joan de Déu Barcelona, Barcelona, Spain
| | - O'Neill D'Cruz
- Consulting and Neurological Services, Chapel Hill, NC, USA
| | - Douglas Nordli
- Division of Pediatric Neurology, Children's Hospital Los Angeles, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA
| | - Shlomo Shinnar
- Departments of Neurology, Pediatrics and Epidemiology and Population Health, Montefiore Medical Center, Albert Einstein College of Medicine, New York, NY, USA
| | - Gregory L Holmes
- Department of Neurological Sciences, Larner College of Medicine, University of Vermont, Burlington, VT, USA.
| | | |
Collapse
|
45
|
Apland JP, Aroniadou-Anderjaska V, Figueiredo TH, Pidoplichko VI, Rossetti K, Braga MFM. Comparing the Antiseizure and Neuroprotective Efficacy of LY293558, Diazepam, Caramiphen, and LY293558-Caramiphen Combination against Soman in a Rat Model Relevant to the Pediatric Population. J Pharmacol Exp Ther 2018; 365:314-326. [PMID: 29467308 PMCID: PMC5878669 DOI: 10.1124/jpet.117.245969] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 02/08/2018] [Indexed: 12/13/2022] Open
Abstract
The currently Food and Drug Administration-approved anticonvulsant for the treatment of status epilepticus (SE) induced by nerve agents is the benzodiazepine diazepam; however, diazepam does not appear to offer neuroprotective benefits. This is of particular concern with respect to the protection of children because, in the developing brain, synaptic transmission mediated via GABAA receptors, the target of diazepam, is weak. In the present study, we exposed 21-day-old male rats to 1.2 × LD50 soman and compared the antiseizure, antilethality, and neuroprotective efficacy of diazepam (10 mg/kg), LY293558 (an AMPA/GluK1 receptor antagonist; 15 mg/kg), caramiphen (CRM, an antimuscarinic with NMDA receptor-antagonistic properties; 50 mg/kg), and LY293558 (15 mg/kg) + CRM (50 mg/kg), administered 1 hour after exposure. Diazepam, LY293558, and LY293558 + CRM, but not CRM alone, terminated SE; LY293558 + CRM treatment acted significantly faster and produced a survival rate greater than 85%. Thirty days after soman exposure, neurodegeneration in limbic regions was most severe in the CRM-treated group, minimal to severe-depending on the region-in the diazepam group, absent to moderate in the LY293558-treated group, and totally absent in the LY293558 + CRM group. Amygdala and hippocampal atrophy, a severe reduction in spontaneous inhibitory activity in the basolateral amygdala, and increased anxiety-like behavior in the open-field and acoustic startle response tests were present in the diazepam and CRM groups, whereas the LY293558 and LY293558 + CRM groups did not differ from controls. The combined administration of LY293558 and CRM, by blocking mainly AMPA, GluK1, and NMDA receptors, is a very effective anticonvulsant and neuroprotective therapy against soman in young rats.
Collapse
Affiliation(s)
- James P Apland
- Neuroscience Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.); and Departments of Anatomy, Physiology, and Genetics (V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Vassiliki Aroniadou-Anderjaska
- Neuroscience Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.); and Departments of Anatomy, Physiology, and Genetics (V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Taiza H Figueiredo
- Neuroscience Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.); and Departments of Anatomy, Physiology, and Genetics (V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Volodymyr I Pidoplichko
- Neuroscience Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.); and Departments of Anatomy, Physiology, and Genetics (V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Katia Rossetti
- Neuroscience Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.); and Departments of Anatomy, Physiology, and Genetics (V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Maria F M Braga
- Neuroscience Branch, U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland (J.P.A.); and Departments of Anatomy, Physiology, and Genetics (V.A.-A., T.H.F., V.I.P., K.R., M.F.M.B.) and Psychiatry (V.A.-A., M.F.M.B.), F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| |
Collapse
|
46
|
Tresguerres M, Hamilton TJ. Acid-base physiology, neurobiology and behaviour in relation to CO 2-induced ocean acidification. ACTA ACUST UNITED AC 2018; 220:2136-2148. [PMID: 28615486 DOI: 10.1242/jeb.144113] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Experimental exposure to ocean and freshwater acidification affects the behaviour of multiple aquatic organisms in laboratory tests. One proposed cause involves an imbalance in plasma chloride and bicarbonate ion concentrations as a result of acid-base regulation, causing the reversal of ionic fluxes through GABAA receptors, which leads to altered neuronal function. This model is exclusively based on differential effects of the GABAA receptor antagonist gabazine on control animals and those exposed to elevated CO2 However, direct measurements of actual chloride and bicarbonate concentrations in neurons and their extracellular fluids and of GABAA receptor properties in aquatic organisms are largely lacking. Similarly, very little is known about potential compensatory mechanisms, and about alternative mechanisms that might lead to ocean acidification-induced behavioural changes. This article reviews the current knowledge on acid-base physiology, neurobiology, pharmacology and behaviour in relation to marine CO2-induced acidification, and identifies important topics for future research that will help us to understand the potential effects of predicted levels of aquatic acidification on organisms.
Collapse
Affiliation(s)
- Martin Tresguerres
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Trevor J Hamilton
- Department of Psychology, MacEwan University, Edmonton, Alberta, Canada T5J 4S2 .,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
| |
Collapse
|
47
|
Abstract
K+-Cl- co-transporter 2 (KCC2/SLC12A5) is a neuronal specific cation chloride co-transporter which is active under isotonic conditions, and thus a key regulator of intracellular Cl- levels. It also has an ion transporter-independent structural role in modulating the maturation and regulation of excitatory glutamatergic synapses. KCC2 levels are developmentally regulated, and a postnatal upregulation of KCC2 generates a low intracellular chloride concentration that allows the neurotransmitters γ-aminobutyric acid (GABA) and glycine to exert inhibitory neurotransmission through its Cl- permeating channel. Functional expression of KCC2 at the neuronal cell surface is necessary for its activity, and impairment in KCC2 cell surface transport and/or internalization may underlie a range of neuropathological conditions. Although recent advances have shed light on a range of cellular mechanisms regulating KCC2 activity, little is known about its membrane trafficking itinerary and regulatory proteins. In this review, known membrane trafficking signals, pathways and mechanisms pertaining to KCC2's functional surface expression are discussed.
Collapse
Affiliation(s)
- Bor Luen Tang
- a Department of Biochemistry, Yong Loo Lin School of Medicine , National University Health System , Singapore.,b NUS Graduate School for Integrative Sciences and Engineering , National University of Singapore , Singapore
| |
Collapse
|
48
|
NMDA Receptors as Voltage Sensors. Methods Mol Biol 2017. [PMID: 28986880 DOI: 10.1007/978-1-4939-7321-7_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
The membrane potential is an essential parameter of a living cell. However, measurements of the membrane potential using conventional techniques are associated with a number of artifacts. Cell-attached recordings of the currents through NMDA receptor channels enable noninvasive measurements of the neuronal membrane potential. This approach overcomes the problem of a leak conductance introduced during intracellular sharp electrode recordings and whole-cell patch-clamp recordings. Here, we describe the procedures of using cell-attached recordings of NMDA receptor channels to measure the true membrane potential.
Collapse
|
49
|
Yang J, Ju L, Jia M, Zhang H, Sun X, Ji M, Yang J, Martynyuk AE. Subsequent maternal separation exacerbates neurobehavioral abnormalities in rats neonatally exposed to sevoflurane anesthesia. Neurosci Lett 2017; 661:137-142. [PMID: 28982596 DOI: 10.1016/j.neulet.2017.09.063] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 09/24/2017] [Accepted: 09/29/2017] [Indexed: 12/16/2022]
Abstract
Several recent studies suggest that in the human population, a routine, short anesthetic in otherwise healthy infants is void of neurodevelopmental insult. On the other hand, many human retrospective epidemiological studies report evidence of cognitive abnormalities in children after testing those who had different anesthesia-requiring procedures in early childhood. We tested in a rat model whether post-anesthesia stressful environmental factors can contribute to developmental abnormalities that were initiated by a relatively short exposure to sevoflurane, the most widely used anesthetic in pediatric anesthesia, whose polyvalent actions include enhancement of gamma-aminobutyric acid type A receptor (GABAAR) activity. Postnatal day 6 (P6) male Sprague-Dawley rats were anesthetized with sevoflurane for 60min. To simulate subsequent stress, the animals were subjected to a single maternal separation for 180min at P10. To study the role of GABAAR-mediated depolarization, subgroups of P6 rats received a single injection of the Na+-K+-2Cl- (NKCC1) inhibitor, bumetanide, prior to initiation of anesthesia with sevoflurane. Rats that were exposed to sevoflurane had decreased hypothalamic K+-2Cl- (KCC2) mRNA level (F(2,13)=3.839, P=0.049), increased NKCC1/KCC2 mRNA ratio (F(2,13)=5.043, P=0.024) and increased corticotropin-releasing hormone (CRH) mRNA level (F(2,12)=9.450, P=0.003) at P10, the age at which maternal separation was imposed. Adult rats, neonatally exposed to a combination of sevoflurane and maternal separation, exhibited increases in the escape latencies greater than animals exposed to sevoflurane only (P=0.012), and only rats in the sevoflurane plus maternal separation group spent significantly less time in the target quadrant during the Morris water maze test (F(4,55)=4.856, P=0.002). Bumetanide ameliorated abnormalities induced by sevoflurane and a combination of sevoflurane plus maternal separation. Neonatal exposure to sevoflurane may sensitize to stressors later in life, and post-exposure stress may exacerbate neurodevelopmental abnormalities even after a relatively short exposure to sevoflurane in rodents. The NKCC1 downregulation prior to exposure to the anesthetic may be therapeutic.
Collapse
Affiliation(s)
- Jiaojiao Yang
- Zhongda Hospital, School of Medicine, Southeast University, Nanjing, China; Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States; Department of Anesthesiology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Lingsha Ju
- Zhongda Hospital, School of Medicine, Southeast University, Nanjing, China; Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States; Department of Anesthesiology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Min Jia
- Department of Anesthesiology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Hui Zhang
- Zhongda Hospital, School of Medicine, Southeast University, Nanjing, China; Department of Anesthesiology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Xiaoru Sun
- Zhongda Hospital, School of Medicine, Southeast University, Nanjing, China; Department of Anesthesiology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Muhuo Ji
- Zhongda Hospital, School of Medicine, Southeast University, Nanjing, China; Department of Anesthesiology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Jianjun Yang
- Zhongda Hospital, School of Medicine, Southeast University, Nanjing, China; Department of Anesthesiology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China.
| | - Anatoly E Martynyuk
- Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, United States; McKnight Brain Institute, University of FL College of Medicine, Gainesville, FL, United States.
| |
Collapse
|
50
|
Pellock JM, Arzimanoglou A, D'Cruz O, Holmes GL, Nordli D, Shinnar S. Extrapolating evidence of antiepileptic drug efficacy in adults to children ≥2 years of age with focal seizures: The case for disease similarity. Epilepsia 2017; 58:1686-1696. [PMID: 28755452 DOI: 10.1111/epi.13859] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/03/2017] [Indexed: 12/18/2022]
Abstract
Expediting pediatric access to new antiseizure drugs is particularly compelling, because epileptic seizures are the most common serious neurological symptom in children. Analysis of antiepileptic drug (AED) efficacy outcomes of randomized controlled trials, conducted during the past 20 years in different populations and a broad range of study sites and countries, has shown considerable consistency for each drug between adult and pediatric populations. Historically, the majority of regulatory approvals for AEDs have been for seizure types and not for specific epilepsy syndromes. Available data, both anatomical and neurophysiological, support a similar pathophysiology of focal seizures in adults and young children, and suggest that by age 2 years the structural and physiological milieu upon which seizures develop is similar. Although the distribution of specific etiologies and epilepsy syndromes is different in children from in adults, this should not impact approvals of efficacy based on seizure type, because the pathophysiology of focal seizures and the drug responsiveness of these seizure types are quite similar. Safety and pharmacokinetics cannot be extrapolated from adults to children. The scientific rationale, clinical consensus, and published data support a future approach accepting efficacy data from adult trials and focusing exclusively on prospective pharmacokinetic, tolerability, and safety studies and long-term follow-up in children. Whereas tolerability studies can be compared easily in children and adults, safety studies require large numbers of patients followed for many years.
Collapse
Affiliation(s)
- John M Pellock
- Department of Neurology, Virginia Commonwealth University, Richmond, Virginia, U.S.A
| | - Alexis Arzimanoglou
- Department of Clinical Epileptology, Sleep Disorders, and Functional Pediatric Neurology, University Hospitals of Lyon, Lyon, France.,Epilepsy, Sleep, and Neurophysiology Section, Neurology Service, Hospital Sant Joan de Déu Barcelona, Barcelona, Spain
| | - O'Neill D'Cruz
- Consulting and Neurological Services, Chapel Hill, North Carolina, U.S.A
| | - Gregory L Holmes
- Department of Neurological Sciences, Larner College of Medicine, University of Vermont, Burlington, Vermont, U.S.A
| | - Douglas Nordli
- Division of Pediatric Neurology, Children's Hospital Los Angeles, Keck School of Medicine of the University of Southern California, Los Angeles, California, U.S.A
| | - Shlomo Shinnar
- Departments of Neurology, Pediatrics, and Epidemiology and Population Health, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A
| | | |
Collapse
|