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Ionescu MI, Grigoras IF, Ionescu RB, Chitimus DM, Haret RM, Ianosi B, Ceanga M, Zagrean AM. Oxytocin Exhibits Neuroprotective Effects on Hippocampal Cultures under Severe Oxygen-Glucose Deprivation Conditions. Curr Issues Mol Biol 2024; 46:6223-6236. [PMID: 38921042 PMCID: PMC11202210 DOI: 10.3390/cimb46060371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2024] [Revised: 06/12/2024] [Accepted: 06/16/2024] [Indexed: 06/27/2024] Open
Abstract
Perinatal asphyxia (PA) and hypoxic-ischemic encephalopathy can result in severe, long-lasting neurological deficits. In vitro models, such as oxygen-glucose deprivation (OGD), are used experimentally to investigate neuronal response to metabolic stress. However, multiple variables can affect the severity level of OGD/PA and may confound any measured treatment effect. Oxytocin (OXT) has emerged as a potential neuroprotective agent against the deleterious effects of PA. Previous studies have demonstrated OXT's potential to enhance neuronal survival in immature hippocampal cultures exposed to OGD, possibly by modulating gamma-aminobutyric acid-A receptor activity. Moreover, OXT's precise impact on developing hippocampal neurons under different severities of OGD/PA remains uncertain. In this study, we investigated the effects of OXT (0.1 µM and 1 µM) on 7-day-old primary rat hippocampal cultures subjected to 2 h OGD/sham normoxic conditions. Cell culture viability was determined using the resazurin assay. Our results indicate that the efficacy of 1 µM OXT treatment varied according to the severity of the OGD-induced lesion, exhibiting a protective effect (p = 0.022) only when cellular viability dropped below 49.41% in non-treated OGD cultures compared to normoxic ones. Furthermore, administration of 0.1 µM OXT did not yield significant effects, irrespective of lesion severity (p > 0.05). These findings suggest that 1 µM OXT treatment during OGD confers neuroprotection exclusively in severe lesions in hippocampal neurons after 7 days in vitro. Further research is warranted to elucidate the mechanisms involved in OXT-mediated neuroprotection.
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Affiliation(s)
- Mara Ioana Ionescu
- Department of Functional Sciences, Division of Physiology II-Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (M.I.I.); (I.-F.G.); (R.-B.I.); (D.M.C.); (R.M.H.); (B.I.)
| | - Ioana-Florentina Grigoras
- Department of Functional Sciences, Division of Physiology II-Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (M.I.I.); (I.-F.G.); (R.-B.I.); (D.M.C.); (R.M.H.); (B.I.)
- Wellcome Centre for Integrative Neuroimaging, Functional MRI of the Brain, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK
| | - Rosana-Bristena Ionescu
- Department of Functional Sciences, Division of Physiology II-Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (M.I.I.); (I.-F.G.); (R.-B.I.); (D.M.C.); (R.M.H.); (B.I.)
- Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 1TN, UK
- NIHR Biomedical Research Centre, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Diana Maria Chitimus
- Department of Functional Sciences, Division of Physiology II-Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (M.I.I.); (I.-F.G.); (R.-B.I.); (D.M.C.); (R.M.H.); (B.I.)
| | - Robert Mihai Haret
- Department of Functional Sciences, Division of Physiology II-Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (M.I.I.); (I.-F.G.); (R.-B.I.); (D.M.C.); (R.M.H.); (B.I.)
- Department of Ophthalmology, University Medical Center Gottingen, 37075 Gottingen, Germany
| | - Bogdan Ianosi
- Department of Functional Sciences, Division of Physiology II-Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (M.I.I.); (I.-F.G.); (R.-B.I.); (D.M.C.); (R.M.H.); (B.I.)
- Department of Neurology, Stroke Unit, Neuromed Campus, Kepler University Hospital, 4020 Linz, Austria
| | - Mihai Ceanga
- Department of Functional Sciences, Division of Physiology II-Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (M.I.I.); (I.-F.G.); (R.-B.I.); (D.M.C.); (R.M.H.); (B.I.)
- Section of Translational Neuroimmunology, Department of Neurology, Jena University Hospital, 07747 Jena, Germany
| | - Ana-Maria Zagrean
- Department of Functional Sciences, Division of Physiology II-Neuroscience, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (M.I.I.); (I.-F.G.); (R.-B.I.); (D.M.C.); (R.M.H.); (B.I.)
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Kok M, Brodsky JL. The biogenesis of potassium transporters: implications of disease-associated mutations. Crit Rev Biochem Mol Biol 2024; 59:154-198. [PMID: 38946646 PMCID: PMC11444911 DOI: 10.1080/10409238.2024.2369986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 06/02/2024] [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.
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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
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Lingampelly SS, Naviaux JC, Heuer LS, Monk JM, Li K, Wang L, Haapanen L, Kelland CA, Van de Water J, Naviaux RK. Metabolic network analysis of pre-ASD newborns and 5-year-old children with autism spectrum disorder. Commun Biol 2024; 7:536. [PMID: 38729981 DOI: 10.1038/s42003-024-06102-y] [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: 10/19/2023] [Accepted: 03/22/2024] [Indexed: 05/12/2024] Open
Abstract
Classical metabolomic and new metabolic network methods were used to study the developmental features of autism spectrum disorder (ASD) in newborns (n = 205) and 5-year-old children (n = 53). Eighty percent of the metabolic impact in ASD was caused by 14 shared biochemical pathways that led to decreased anti-inflammatory and antioxidant defenses, and to increased physiologic stress molecules like lactate, glycerol, cholesterol, and ceramides. CIRCOS plots and a new metabolic network parameter,V ° net, revealed differences in both the kind and degree of network connectivity. Of 50 biochemical pathways and 450 polar and lipid metabolites examined, the developmental regulation of the purine network was most changed. Purine network hub analysis revealed a 17-fold reversal in typically developing children. This purine network reversal did not occur in ASD. These results revealed previously unknown metabolic phenotypes, identified new developmental states of the metabolic correlation network, and underscored the role of mitochondrial functional changes, purine metabolism, and purinergic signaling in autism spectrum disorder.
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Affiliation(s)
- Sai Sachin Lingampelly
- The Mitochondrial and Metabolic Disease Center, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA
- Department of Medicine, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA
| | - Jane C Naviaux
- The Mitochondrial and Metabolic Disease Center, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA
- Department of Neuroscience, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA
| | - Luke S Heuer
- The UC Davis MIND Institute, University of California, Davis, Davis, CA, 95616, USA
| | - Jonathan M Monk
- The Mitochondrial and Metabolic Disease Center, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA
- Department of Medicine, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA
| | - Kefeng Li
- The Mitochondrial and Metabolic Disease Center, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA
- Department of Medicine, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA
- Macao Polytechnic University, Macau, China
| | - Lin Wang
- The Mitochondrial and Metabolic Disease Center, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA
- Department of Medicine, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA
| | - Lori Haapanen
- The UC Davis MIND Institute, University of California, Davis, Davis, CA, 95616, USA
| | - Chelsea A Kelland
- The UC Davis MIND Institute, University of California, Davis, Davis, CA, 95616, USA
| | - Judy Van de Water
- The UC Davis MIND Institute, University of California, Davis, Davis, CA, 95616, USA
- Department of Rheumatology and Allergy, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, USA
| | - Robert K Naviaux
- The Mitochondrial and Metabolic Disease Center, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA.
- Department of Medicine, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA.
- Department of Pediatrics, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA.
- Department of Pathology, University of California, San Diego School of Medicine, San Diego, CA, 92103-8467, USA.
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Sun C, Deng J, Ma Y, Meng F, Cui X, Li M, Li J, Li J, Yin P, Kong L, Zhang L, Tang P. The dual role of microglia in neuropathic pain after spinal cord injury: Detrimental and protective effects. Exp Neurol 2023; 370:114570. [PMID: 37852469 DOI: 10.1016/j.expneurol.2023.114570] [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: 07/04/2023] [Revised: 09/21/2023] [Accepted: 10/11/2023] [Indexed: 10/20/2023]
Abstract
Spinal cord injury (SCI) is a debilitating condition that is frequently accompanied by neuropathic pain, resulting in significant physical and psychological harm to a vast number of individuals globally. Despite the high prevalence of neuropathic pain following SCI, the precise underlying mechanism remains incompletely understood. Microglia are a type of innate immune cell that are present in the central nervous system (CNS). They have been observed to have a significant impact on neuropathic pain following SCI. This article presents a comprehensive overview of recent advances in understanding the role of microglia in the development of neuropathic pain following SCI. Specifically, the article delves into the detrimental and protective effects of microglia on neuropathic pain following SCI, as well as the mechanisms underlying their interconversion. Furthermore, the article provides a thorough overview of potential avenues for future research in this area.
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Affiliation(s)
- Chang Sun
- Department of Orthopedics, The Fourth Medical Center of Chinese PLA General Hospital, Beijing, China; National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, Beijing, China; Department of Orthopedics, Air Force Medical Center, PLA, Beijing, China
| | - Junhao Deng
- Department of Orthopedics, The Fourth Medical Center of Chinese PLA General Hospital, Beijing, China; National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, Beijing, China; School of Life Sciences, Tsinghua University, Beijing, China; State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua University, Beijing, China; IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing, China
| | - Yifei Ma
- School of Medicine, Nankai University, Tianjin, China
| | - Fanqi Meng
- Department of Anesthesiology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Xiang Cui
- Department of Orthopedics, The Fourth Medical Center of Chinese PLA General Hospital, Beijing, China; National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, Beijing, China
| | - Ming Li
- Department of Orthopedics, The Fourth Medical Center of Chinese PLA General Hospital, Beijing, China; National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, Beijing, China
| | - Jiantao Li
- Department of Orthopedics, The Fourth Medical Center of Chinese PLA General Hospital, Beijing, China; National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, Beijing, China
| | - Jia Li
- Department of Orthopedics, The Fourth Medical Center of Chinese PLA General Hospital, Beijing, China; National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, Beijing, China
| | - Pengbin Yin
- Department of Orthopedics, The Fourth Medical Center of Chinese PLA General Hospital, Beijing, China; National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, Beijing, China
| | - Lingjie Kong
- State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua University, Beijing, China; IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing, China.
| | - Licheng Zhang
- Department of Orthopedics, The Fourth Medical Center of Chinese PLA General Hospital, Beijing, China; National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, Beijing, China.
| | - Peifu Tang
- Department of Orthopedics, The Fourth Medical Center of Chinese PLA General Hospital, Beijing, China; National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, Beijing, China.
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Fame RM, Xu H, Pragana A, Lehtinen M. Age-appropriate potassium clearance from perinatal cerebrospinal fluid depends on choroid plexus NKCC1. Fluids Barriers CNS 2023; 20:45. [PMID: 37328833 PMCID: PMC10276483 DOI: 10.1186/s12987-023-00438-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 05/06/2023] [Indexed: 06/18/2023] Open
Abstract
Regulation of the volume and electrolyte composition of the cerebrospinal fluid (CSF) is vital for brain development and function. The Na-K-Cl co-transporter NKCC1 in the choroid plexus (ChP) plays key roles in regulating CSF volume by co-transporting ions and mediating same-direction water movements. Our previous study showed ChP NKCC1 is highly phosphorylated in neonatal mice as the CSF K+ level drastically decreases and that overexpression of NKCC1 in the ChP accelerates CSF K+ clearance and reduces ventricle size [1]. These data suggest that NKCC1 mediates CSF K+ clearance following birth in mice. In this current study, we used CRISPR technology to create a conditional NKCC1 knockout mouse line and evaluated CSF K+ by Inductively Coupled Plasma Optical Emission spectroscopy (ICP-OES). We demonstrated ChP-specific reduction of total and phosphorylated NKCC1 in neonatal mice following embryonic intraventricular delivery of Cre recombinase using AAV2/5. ChP-NKCC1 knockdown was accompanied by a delayed perinatal clearance of CSF K+. No gross morphological disruptions were observed in the cerebral cortex. We extended our previous results by showing embryonic and perinatal rats shared key characteristics with mice, including decreased ChP NKCC1 expression level, increased ChP NKCC1 phosphorylation state, and increased CSF K+ levels compared to adult. Collectively, these follow up data support ChP NKCC1's role in age-appropriate CSF K+ clearance during neonatal development.
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Affiliation(s)
- Ryann M Fame
- Department of Pathology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
- Present Address: Department of Neurosurgery, Stanford University, Stanford, CA, 94305, USA
| | - Huixin Xu
- Department of Pathology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Aja Pragana
- Department of Pathology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Maria Lehtinen
- Department of Pathology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
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6
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Firestone E, Sonoda M, Kuroda N, Sakakura K, Jeong JW, Lee MH, Wada K, Takayama Y, Iijima K, Iwasaki M, Miyazaki T, Asano E. Sevoflurane-induced high-frequency oscillations, effective connectivity and intraoperative classification of epileptic brain areas. Clin Neurophysiol 2023; 150:17-30. [PMID: 36989866 PMCID: PMC10192072 DOI: 10.1016/j.clinph.2023.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 02/27/2023] [Accepted: 03/02/2023] [Indexed: 03/18/2023]
Abstract
OBJECTIVE To determine how sevoflurane anesthesia modulates intraoperative epilepsy biomarkers on electrocorticography, including high-frequency oscillation (HFO) effective connectivity (EC), and to investigate their relation to epileptogenicity and anatomical white matter. METHODS We studied eight pediatric drug-resistant focal epilepsy patients who achieved seizure control after invasive monitoring and resective surgery. We visualized spatial distributions of the electrocorticography biomarkers at an oxygen baseline, three time-points while sevoflurane was increasing, and at a plateau of 2 minimum alveolar concentration (MAC) sevoflurane. HFO EC was combined with diffusion-weighted imaging, in dynamic tractography. RESULTS Intraoperative HFO EC diffusely increased as a function of sevoflurane concentration, although most in epileptogenic sites (defined as those included in the resection); their ability to classify epileptogenicity was optimized at sevoflurane 2 MAC. HFO EC could be visualized on major white matter tracts, as a function of sevoflurane level. CONCLUSIONS The results strengthened the hypothesis that sevoflurane-activated HFO biomarkers may help intraoperatively localize the epileptogenic zone. SIGNIFICANCE Our results help characterize how HFOs at non-epileptogenic and epileptogenic networks respond to sevoflurane. It may be warranted to establish a normative HFO atlas incorporating the modifying effects of sevoflurane and major white matter pathways, as critical reference in epilepsy presurgical evaluation.
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Affiliation(s)
- Ethan Firestone
- Department of Pediatrics, Children's Hospital of Michigan, Detroit Medical Center,Wayne State University, Detroit, MI 48201, USA; Department of Physiology, Wayne State University, Detroit, MI 48201, USA
| | - Masaki Sonoda
- Department of Pediatrics, Children's Hospital of Michigan, Detroit Medical Center,Wayne State University, Detroit, MI 48201, USA; Department of Neurosurgery, Yokohama City University Graduate School of Medicine, Yokohama 2360004, Japan
| | - Naoto Kuroda
- Department of Pediatrics, Children's Hospital of Michigan, Detroit Medical Center,Wayne State University, Detroit, MI 48201, USA; Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai 9808575, Japan
| | - Kazuki Sakakura
- Department of Pediatrics, Children's Hospital of Michigan, Detroit Medical Center,Wayne State University, Detroit, MI 48201, USA; Department of Neurosurgery, University of Tsukuba, Tsukuba 3058575, Japan
| | - Jeong-Won Jeong
- Department of Pediatrics, Children's Hospital of Michigan, Detroit Medical Center,Wayne State University, Detroit, MI 48201, USA; Department of Neurology, Children's Hospital of Michigan, Detroit Medical Center, Wayne State University, Detroit, MI 48201, USA
| | - Min-Hee Lee
- Department of Pediatrics, Children's Hospital of Michigan, Detroit Medical Center,Wayne State University, Detroit, MI 48201, USA
| | - Keiko Wada
- Department of Anesthesiology, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo 1878551, Japan; Department of Anesthesiology and Critical Care, Yokohama City University Graduate School of Medicine, Yokohama 2360004, Japan
| | - Yutaro Takayama
- Department of Neurosurgery, Yokohama City University Graduate School of Medicine, Yokohama 2360004, Japan; Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo 1878551, Japan
| | - Keiya Iijima
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo 1878551, Japan
| | - Masaki Iwasaki
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo 1878551, Japan
| | - Tomoyuki Miyazaki
- Department of Anesthesiology, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo 1878551, Japan; Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 2360004, Japan
| | - Eishi Asano
- Department of Pediatrics, Children's Hospital of Michigan, Detroit Medical Center,Wayne State University, Detroit, MI 48201, USA; Department of Neurology, Children's Hospital of Michigan, Detroit Medical Center, Wayne State University, Detroit, MI 48201, USA.
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7
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Welzel B, Johne M, Löscher W. Bumetanide potentiates the anti-seizure and disease-modifying effects of midazolam in a noninvasive rat model of term birth asphyxia. Epilepsy Behav 2023; 142:109189. [PMID: 37037061 DOI: 10.1016/j.yebeh.2023.109189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 03/15/2023] [Accepted: 03/16/2023] [Indexed: 04/12/2023]
Abstract
Birth asphyxia and the resulting hypoxic-ischemic encephalopathy (HIE) are highly associated with perinatal and neonatal death, neonatal seizures, and an adverse later-life outcome. Currently used drugs, including phenobarbital and midazolam, have limited efficacy to suppress neonatal seizures. There is a medical need to develop new therapies that not only suppress neonatal seizures but also prevent later-life consequences. We have previously shown that the loop diuretic bumetanide does not potentiate the effects of phenobarbital in a rat model of birth asphyxia. Here we compared the effects of bumetanide (0.3 or 10 mg/kg i.p.), midazolam (1 mg/kg i.p.), and a combination of bumetanide and midazolam on neonatal seizures and later-life outcomes in this model. While bumetanide at either dose was ineffective when administered alone, the higher dose of bumetanide markedly potentiated midazolam's effect on neonatal seizures. Median bumetanide brain levels (0.47-0.53 µM) obtained with the higher dose were in the range known to inhibit the Na-K-Cl-cotransporter NKCC1 but it remains to be determined whether brain NKCC1 inhibition was underlying the potentiation of midazolam. When behavioral and cognitive alterations were examined over three months after asphyxia, treatment with the bumetanide/midazolam combination, but not with bumetanide or midazolam alone, prevented impairment of learning and memory. Furthermore, the combination prevented the loss of neurons in the dentate hilus and aberrant mossy fiber sprouting in the CA3a area of the hippocampus. The molecular mechanisms that explain that bumetanide potentiates midazolam but not phenobarbital in the rat model of birth asphyxia remain to be determined.
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Affiliation(s)
- Björn Welzel
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience Hannover, Germany
| | - Marie Johne
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience Hannover, Germany.
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8
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Traut J, Mengual JP, Meijer EJ, McKillop LE, Alfonsa H, Hoerder-Suabedissen A, Song SH, Fehér KD, Riemann D, Molnar Z, Akerman CJ, Vyazovskiy VV, Krone LB. Effects of clozapine-N-oxide and compound 21 on sleep in laboratory mice. eLife 2023; 12:e84740. [PMID: 36892930 PMCID: PMC9998087 DOI: 10.7554/elife.84740] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 01/03/2023] [Indexed: 03/10/2023] Open
Abstract
Designer receptors exclusively activated by designer drugs (DREADDs) are chemogenetic tools for remote control of targeted cell populations using chemical actuators that bind to modified receptors. Despite the popularity of DREADDs in neuroscience and sleep research, potential effects of the DREADD actuator clozapine-N-oxide (CNO) on sleep have never been systematically tested. Here, we show that intraperitoneal injections of commonly used CNO doses (1, 5, and 10 mg/kg) alter sleep in wild-type male laboratory mice. Using electroencephalography (EEG) and electromyography (EMG) to analyse sleep, we found a dose-dependent suppression of rapid eye movement (REM) sleep, changes in EEG spectral power during non-REM (NREM) sleep, and altered sleep architecture in a pattern previously reported for clozapine. Effects of CNO on sleep could arise from back-metabolism to clozapine or binding to endogenous neurotransmitter receptors. Interestingly, we found that the novel DREADD actuator, compound 21 (C21, 3 mg/kg), similarly modulates sleep despite a lack of back-metabolism to clozapine. Our results demonstrate that both CNO and C21 can modulate sleep of mice not expressing DREADD receptors. This implies that back-metabolism to clozapine is not the sole mechanism underlying side effects of chemogenetic actuators. Therefore, any chemogenetic experiment should include a DREADD-free control group injected with the same CNO, C21, or newly developed actuator. We suggest that electrophysiological sleep assessment could serve as a sensitive tool to test the biological inertness of novel chemogenetic actuators.
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Affiliation(s)
- Janine Traut
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of FreiburgFreiburgGermany
- Department of Physiology, Anatomy and Genetics, University of OxfordOxfordUnited Kingdom
- Sir Jules Thorn Sleep and Circadian Neuroscience Institute, University of OxfordOxfordUnited Kingdom
| | - Jose Prius Mengual
- Department of Physiology, Anatomy and Genetics, University of OxfordOxfordUnited Kingdom
- Sir Jules Thorn Sleep and Circadian Neuroscience Institute, University of OxfordOxfordUnited Kingdom
- The Kavli Institute for Nanoscience DiscoveryOxfordUnited Kingdom
| | - Elise J Meijer
- Department of Physiology, Anatomy and Genetics, University of OxfordOxfordUnited Kingdom
- Sir Jules Thorn Sleep and Circadian Neuroscience Institute, University of OxfordOxfordUnited Kingdom
- The Kavli Institute for Nanoscience DiscoveryOxfordUnited Kingdom
| | - Laura E McKillop
- Department of Physiology, Anatomy and Genetics, University of OxfordOxfordUnited Kingdom
- Sir Jules Thorn Sleep and Circadian Neuroscience Institute, University of OxfordOxfordUnited Kingdom
| | - Hannah Alfonsa
- Department of Pharmacology, University of OxfordOxfordUnited Kingdom
| | | | - Seo Ho Song
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Harvard Medical SchoolBostonUnited States
| | - Kristoffer D Fehér
- Geneva University Hospitals (HUG), Division of Psychiatric SpecialtiesGenevaSwitzerland
- University Hospital of Psychiatry and Psychotherapy, University of BernBernSwitzerland
| | - Dieter Riemann
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of FreiburgFreiburgGermany
- Sir Jules Thorn Sleep and Circadian Neuroscience Institute, University of OxfordOxfordUnited Kingdom
| | - Zoltan Molnar
- Department of Physiology, Anatomy and Genetics, University of OxfordOxfordUnited Kingdom
| | - Colin J Akerman
- Department of Pharmacology, University of OxfordOxfordUnited Kingdom
| | - Vladyslav V Vyazovskiy
- Department of Physiology, Anatomy and Genetics, University of OxfordOxfordUnited Kingdom
- Sir Jules Thorn Sleep and Circadian Neuroscience Institute, University of OxfordOxfordUnited Kingdom
- The Kavli Institute for Nanoscience DiscoveryOxfordUnited Kingdom
| | - Lukas B Krone
- Department of Physiology, Anatomy and Genetics, University of OxfordOxfordUnited Kingdom
- Sir Jules Thorn Sleep and Circadian Neuroscience Institute, University of OxfordOxfordUnited Kingdom
- The Kavli Institute for Nanoscience DiscoveryOxfordUnited Kingdom
- University Hospital of Psychiatry and Psychotherapy, University of BernBernSwitzerland
- Centre for Experimental Neurology, University of BernBernSwitzerland
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Haratizadeh S, Ranjbar M, Darvishzadeh-Mahani F, Basiri M, Nozari M. The effects of postnatal erythropoietin and nano-erythropoietin on behavioral alterations by mediating K-Cl co-transporter 2 in the valproic acid-induced rat model of autism. Dev Psychobiol 2023; 65:e22353. [PMID: 36567653 DOI: 10.1002/dev.22353] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/28/2022] [Accepted: 10/31/2022] [Indexed: 12/14/2022]
Abstract
In this study, based on the excitatory/inhibitory imbalance theory of autism, the time window of GABA switch, the role of K-Cl co-transporter 2 (KCC2) in adjustment GABA switch, and brain permeability to erythropoietin (EPO), the effects of postnatal -EPO and- nano- erythropoietin (NEPO) have been evaluated in the valproic acid (VPA) rat model of autism. The VPA was administered for animal modeling of autism at gestational day (GD) 12.5 (600 mg/kg). Male offsprings were injected with EPO and NEPO in a clinically proper postnatal dosing regimen on postnatal days (PND) 1-5, and autistic-like behaviors were tested at the end of the first month. Then animals were sacrificed, and neuron morphology and KCC2 expression were examined by Nissl staining and Western blot. According to our findings, high-dose NEPO improved autism-associated phenotypes. Neuroprotective effects of EPO and NEPO have been shown in the hippocampus. Postnatal NEPO treatment reversed KCC2 expression abnormalities induced by prenatal VPA. Our results might support the role of KCC2 in ASD and the excitatory/inhibitory imbalance hypothesis. We suggested Nano- erythropoietin and other KCC2 interventions as a new approach to the early treatment and prevention of autism.
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Affiliation(s)
- Sara Haratizadeh
- Student Research Committee, Kerman University of Medical Sciences, Kerman, Iran.,Department of Anatomical Sciences, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Mehdi Ranjbar
- Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Fatemeh Darvishzadeh-Mahani
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohsen Basiri
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran.,Department of Anatomical Sciences, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Masoumeh Nozari
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
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10
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Katnik C, Cuevas J. Loop Diuretics Inhibit Ischemia-Induced Intracellular Ca 2+ Overload in Neurons via the Inhibition of Voltage-Gated Ca 2+ and Na + Channels. Front Pharmacol 2021; 12:732922. [PMID: 34603048 PMCID: PMC8479115 DOI: 10.3389/fphar.2021.732922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 08/10/2021] [Indexed: 11/13/2022] Open
Abstract
One consequence of ischemic stroke is disruption of intracellular ionic homeostasis. Intracellular overload of both Na+ and Ca2+ has been linked to neuronal death in this pathophysiological state. The etiology of ionic imbalances resulting from stroke-induced ischemia and acidosis includes the dysregulation of multiple plasma membrane transport proteins, such as increased activity of sodium-potassium-chloride cotransporter-1 (NKCC-1). Experiments using NKCC1 antagonists, bumetanide (BMN) and ethacrynic acid (EA), were carried out to determine if inhibition of this cotransporter affects Na+ and Ca2+ overload observed following in vitro ischemia-acidosis. Fluorometric Ca2+ and Na+ measurements were performed using cultured cortical neurons, and measurements of whole-cell membrane currents were used to determine target(s) of BMN and EA, other than the electroneutral NKCC-1. Both BMN and EA depressed ischemia-acidosis induced [Ca2+]i overload without appreciably reducing [Na+]i increases. Voltage-gated Ca2+ channels were inhibited by both BMN and EA with half-maximal inhibitory concentration (IC50) values of 4 and 36 μM, respectively. Similarly, voltage-gated Na+ channels were blocked by BMN and EA with IC50 values of 13 and 30 μM, respectively. However, neither BMN nor EA affected currents mediated by acid-sensing ion channels or ionotropic glutamatergic receptors, both of which are known to produce [Ca2+]i overload following ischemia. Data suggest that loop diuretics effectively inhibit voltage-gated Ca2+ and Na+ channels at clinically relevant concentrations, and block of these channels by these compounds likely contributes to their clinical effects. Importantly, inhibition of these channels, and not NKCC1, by loop diuretics reduces [Ca2+]i overload in neurons during ischemia-acidosis, and thus BMN and EA could potentially be used therapeutically to lessen injury following ischemic stroke.
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Affiliation(s)
- Christopher Katnik
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Javier Cuevas
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
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11
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Dubanet O, Ferreira Gomes Da Silva A, Frick A, Hirase H, Beyeler A, Leinekugel X. Probing the polarity of spontaneous perisomatic GABAergic synaptic transmission in the mouse CA3 circuit in vivo. Cell Rep 2021; 36:109381. [PMID: 34260906 DOI: 10.1016/j.celrep.2021.109381] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 11/18/2020] [Accepted: 06/18/2021] [Indexed: 11/27/2022] Open
Abstract
The hypothesis that reversed, excitatory GABA may be involved in various brain pathologies, including epileptogenesis, is appealing but controversial because of the technical difficulty of probing endogenous GABAergic synaptic function in vivo. We overcome this challenge by non-invasive extracellular recording of neuronal firing responses to optogenetically evoked and spontaneously occurring inhibitory perisomatic GABAergic field potentials, generated by individual parvalbumin interneurons on their target pyramidal cells. Our direct probing of GABAergic transmission suggests a rather anecdotal participation of excitatory GABA in two specific models of epileptogenesis in the mouse CA3 circuit in vivo, even though this does not preclude its expression in other brain areas or pathological conditions. Our approach allows the detection of distinct alterations of inhibition during spontaneous activity in vivo, with high sensitivity. It represents a promising tool for the investigation of excitatory GABA in different pathological conditions that may affect the hippocampal circuit.
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Affiliation(s)
- Olivier Dubanet
- University of Bordeaux, INSERM U1215, Neurocentre Magendie, 33077 Bordeaux, France
| | - Arnaldo Ferreira Gomes Da Silva
- University of Bordeaux, INSERM U1215, Neurocentre Magendie, 33077 Bordeaux, France; INMED, INSERM, Aix Marseille Univ, France
| | - Andreas Frick
- University of Bordeaux, INSERM U1215, Neurocentre Magendie, 33077 Bordeaux, France
| | - Hajime Hirase
- Center for Translational Neuromedicine, University of Copenhagen, Copenhagen, Denmark
| | - Anna Beyeler
- University of Bordeaux, INSERM U1215, Neurocentre Magendie, 33077 Bordeaux, France
| | - Xavier Leinekugel
- University of Bordeaux, INSERM U1215, Neurocentre Magendie, 33077 Bordeaux, France; INMED, INSERM, Aix Marseille Univ, France.
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12
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Johne M, Käufer C, Römermann K, Gailus B, Gericke B, Löscher W. A combination of phenobarbital and the bumetanide derivative bumepamine prevents neonatal seizures and subsequent hippocampal neurodegeneration in a rat model of birth asphyxia. Epilepsia 2021; 62:1460-1471. [PMID: 33955541 DOI: 10.1111/epi.16912] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/07/2021] [Accepted: 04/07/2021] [Indexed: 12/26/2022]
Abstract
OBJECTIVES Bumetanide was suggested as an adjunct to phenobarbital for suppression of neonatal seizures. This suggestion was based on the idea that bumetanide, by reducing intraneuronal chloride accumulation through inhibition of the Na-K-2Cl cotransporter NKCC1, may attenuate or abolish depolarizing γ-aminobutyric acid (GABA) responses caused by birth asphyxia. However, a first proof-of-concept clinical trial failed. This could have had several reasons, including bumetanide's poor brain penetration, the wide cellular NKCC1 expression pattern in the brain, and problems with the general concept of NKCC1's role in neonatal seizures. We recently replicated the clinical failure of bumetanide to potentiate phenobarbital's effect in a novel rat model of birth asphyxia. In this study, a clinically relevant dose (0.3 mg/kg) of bumetanide was used that does not lead to NKCC1-inhibitory brain levels. The aim of the present experiments was to examine whether a much higher dose (10 mg/kg) of bumetanide is capable of potentiating phenobarbital in this rat model. Furthermore, the effects of the two lipophilic bumetanide derivatives, the ester prodrug N,N-dimethylaminoethylester of bumetanide (DIMAEB) and the benzylamine derivative bumepamine, were examined at equimolar doses. METHODS Intermittent asphyxia was induced for 30 min by exposing male and female P11 rat pups to three 7 + 3 min cycles of 9% and 5% O2 at constant 20% CO2 . All control pups exhibited neonatal seizures after the asphyxia. RESULTS Even at 10 mg/kg, bumetanide did not potentiate the effect of a submaximal dose (15 mg/kg) of phenobarbital on seizure incidence, whereas a significant suppression of neonatal seizures was determined for combinations of phenobarbital with DIMAEB or, more effectively, bumepamine, which, however, does not inhibit NKCC1. Of interest, the bumepamine/phenobarbital combination prevented the neurodegenerative consequences of asphyxia and seizures in the hippocampus. SIGNIFICANCE Both bumepamine and DIMAEB are promising tools that may help to develop more effective lead compounds for clinical trials.
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Affiliation(s)
- Marie Johne
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience Hannover, Hannover, Germany
| | - Christopher Käufer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Kerstin Römermann
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Björn Gailus
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience Hannover, Hannover, Germany
| | - Birthe Gericke
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience Hannover, Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience Hannover, Hannover, Germany
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13
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Hampel P, Johne M, Gailus B, Vogel A, Schidlitzki A, Gericke B, Töllner K, Theilmann W, Käufer C, Römermann K, Kaila K, Löscher W. Deletion of the Na-K-2Cl cotransporter NKCC1 results in a more severe epileptic phenotype in the intrahippocampal kainate mouse model of temporal lobe epilepsy. Neurobiol Dis 2021; 152:105297. [PMID: 33581254 DOI: 10.1016/j.nbd.2021.105297] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 01/29/2021] [Accepted: 02/06/2021] [Indexed: 12/18/2022] Open
Abstract
Increased neuronal expression of the Na-K-2Cl cotransporter NKCC1 has been implicated in the generation of seizures and epilepsy. However, conclusions from studies on the NKCC1-specific inhibitor, bumetanide, are equivocal, which is a consequence of the multiple potential cellular targets and poor brain penetration of this drug. Here, we used Nkcc1 knockout (KO) and wildtype (WT) littermate control mice to study the ictogenic and epileptogenic effects of intrahippocampal injection of kainate. Kainate (0.23 μg in 50 nl) induced limbic status epilepticus (SE) in both KO and WT mice with similar incidence, latency to SE onset, and SE duration, but the number of intermittent generalized convulsive seizures during SE was significantly higher in Nkcc1 KO mice, indicating increased SE severity. Following SE, spontaneous recurrent seizures (SRS) were recorded by continuous (24/7) video/EEG monitoring at 0-1, 4-5, and 12-13 weeks after kainate, using depth electrodes in the ipsilateral hippocampus. Latency to onset of electrographic SRS and the incidence of electrographic SRS were similar in WT and KO mice. However, the frequency of electrographic seizures was lower whereas the frequency of electroclinical seizures was higher in Nkcc1 KO mice, indicating a facilitated progression from electrographic to electroclinical seizures during chronic epilepsy, and a more severe epileptic phenotype, in the absence of NKCC1. The present findings suggest that NKCC1 is dispensable for the induction, progression and manifestation of epilepsy, and they do not support the widely held notion that inhibition of NKCC1 in the brain is a useful strategy for preventing or modifying epilepsy.
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Affiliation(s)
- Philip Hampel
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany; Neurona Therapeutics, San Francisco, CA, USA
| | - Marie Johne
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Björn Gailus
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Alexandra Vogel
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
| | - Alina Schidlitzki
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
| | - Birthe Gericke
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Kathrin Töllner
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
| | - Wiebke Theilmann
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
| | - Christopher Käufer
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
| | - Kerstin Römermann
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
| | - Kai Kaila
- Molecular and Integrative Biosciences and Neuroscience Center (HiLIFE), University of Helsinki, Finland
| | - Wolfgang Löscher
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
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14
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Yates N, Gunn AJ, Bennet L, Dhillon SK, Davidson JO. Preventing Brain Injury in the Preterm Infant-Current Controversies and Potential Therapies. Int J Mol Sci 2021; 22:1671. [PMID: 33562339 PMCID: PMC7915709 DOI: 10.3390/ijms22041671] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/03/2021] [Accepted: 02/05/2021] [Indexed: 12/12/2022] Open
Abstract
Preterm birth is associated with a high risk of morbidity and mortality including brain damage and cerebral palsy. The development of brain injury in the preterm infant may be influenced by many factors including perinatal asphyxia, infection/inflammation, chronic hypoxia and exposure to treatments such as mechanical ventilation and corticosteroids. There are currently very limited treatment options available. In clinical trials, magnesium sulfate has been associated with a small, significant reduction in the risk of cerebral palsy and gross motor dysfunction in early childhood but no effect on the combined outcome of death or disability, and longer-term follow up to date has not shown improved neurological outcomes in school-age children. Recombinant erythropoietin has shown neuroprotective potential in preclinical studies but two large randomized trials, in extremely preterm infants, of treatment started within 24 or 48 h of birth showed no effect on the risk of severe neurodevelopmental impairment or death at 2 years of age. Preclinical studies have highlighted a number of promising neuroprotective treatments, such as therapeutic hypothermia, melatonin, human amnion epithelial cells, umbilical cord blood and vitamin D supplementation, which may be useful at reducing brain damage in preterm infants. Moreover, refinements of clinical care of preterm infants have the potential to influence later neurological outcomes, including the administration of antenatal and postnatal corticosteroids and more accurate identification and targeted treatment of seizures.
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Affiliation(s)
- Nathanael Yates
- The Queensland Brain Institute, University of Queensland, St Lucia, QLD 4072, Australia;
- School of Human Sciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Alistair J. Gunn
- The Department of Physiology, University of Auckland, Auckland 1023, New Zealand; (A.J.G.); (L.B.); (S.K.D.)
| | - Laura Bennet
- The Department of Physiology, University of Auckland, Auckland 1023, New Zealand; (A.J.G.); (L.B.); (S.K.D.)
| | - Simerdeep K. Dhillon
- The Department of Physiology, University of Auckland, Auckland 1023, New Zealand; (A.J.G.); (L.B.); (S.K.D.)
| | - Joanne O. Davidson
- The Department of Physiology, University of Auckland, Auckland 1023, New Zealand; (A.J.G.); (L.B.); (S.K.D.)
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15
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Hampel P, Römermann K, Gailus B, Johne M, Gericke B, Kaczmarek E, Löscher W. Effects of the NKCC1 inhibitors bumetanide, azosemide, and torasemide alone or in combination with phenobarbital on seizure threshold in epileptic and nonepileptic mice. Neuropharmacology 2021; 185:108449. [PMID: 33450274 DOI: 10.1016/j.neuropharm.2021.108449] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 12/07/2020] [Accepted: 12/22/2020] [Indexed: 12/31/2022]
Abstract
The sodium-potassium-chloride (Na-K-Cl) cotransporter NKCC1 is found in the plasma membrane of a wide variety of cell types, including neurons, glia and endothelial cells in the brain. Increased expression of neuronal NKCC1 has been implicated in several brain disorders, including neonatal seizures and epilepsy. The loop diuretic and NKCC inhibitor bumetanide has been evaluated as an antiseizure agent alone or together with approved antiseizure drugs such as phenobarbital (PB) in pre-clinical and clinical studies with varying results. The equivocal efficacy of bumetanide may be a result of its poor brain penetration. We recently reported that the loop diuretic azosemide is more potent to inhibit NKCC1 than bumetanide. In contrast to bumetanide, azosemide is not acidic, which should favor its brain penetration. Thus, azosemide may be a promising alternative to bumetanide for treatment of brain disorders such as epilepsy. In the present study, we determined the effect of azosemide and bumetanide on seizure threshold in adult epileptic mice. A structurally related non-acidic loop diuretic, torasemide, which also blocks NKCC1, was included in the experiments. The drug effects were assessed by determing the maximal electroshock seizure threshold (MEST) in epileptic vs. nonepileptic mice. Epilepsy was induced by pilocarpine, which was shown to produce long-lasting increases in NKCC1 in the hippocampus, whereas MEST did not alter NKCC1 mRNA in this region. None of the three loop diuretics increased MEST or the effect of PB on MEST in nonepileptic mice. In epileptic mice, all three diuretics significantly increased PB's seizure threshold increasing efficacy, but the effect was variable upon repeated MEST determinations and not correlated with the drugs' diuretic potency. These data may indicate that inhibition of NKCC1 by loop diuretics is not an effective means of increasing seizure threshold in adult epilepsy.
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Affiliation(s)
- Philip Hampel
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
| | - Kerstin Römermann
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Björn Gailus
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Marie Johne
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Birthe Gericke
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Edith Kaczmarek
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
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16
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Johne M, Römermann K, Hampel P, Gailus B, Theilmann W, Ala-Kurikka T, Kaila K, Löscher W. Phenobarbital and midazolam suppress neonatal seizures in a noninvasive rat model of birth asphyxia, whereas bumetanide is ineffective. Epilepsia 2020; 62:920-934. [PMID: 33258158 DOI: 10.1111/epi.16778] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 11/03/2020] [Accepted: 11/05/2020] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Neonatal seizures are the most frequent type of neurological emergency in newborn infants, often being a consequence of prolonged perinatal asphyxia. Phenobarbital is currently the most widely used antiseizure drug for treatment of neonatal seizures, but fails to stop them in ~50% of cases. In a neonatal hypoxia-only model based on 11-day-old (P11) rats, the NKCC1 inhibitor bumetanide was reported to potentiate the antiseizure activity of phenobarbital, whereas it was ineffective in a human trial in neonates. The aim of this study was to evaluate the effect of clinically relevant doses of bumetanide as add-on to phenobarbital on neonatal seizures in a noninvasive model of birth asphyxia in P11 rats, designed for better translation to the human term neonate. METHODS Intermittent asphyxia was induced for 30 minutes by exposing the rat pups to three 7 + 3-minute cycles of 9% and 5% O2 at constant 20% CO2 . Drug treatments were administered intraperitoneally either before or immediately after asphyxia. RESULTS All untreated rat pups had seizures within 10 minutes after termination of asphyxia. Phenobarbital significantly blocked seizures when applied before asphyxia at 30 mg/kg but not 15 mg/kg. Administration of phenobarbital after asphyxia was ineffective, whereas midazolam (0.3 or 1 mg/kg) exerted significant antiseizure effects when administered before or after asphyxia. In general, focal seizures were more resistant to treatment than generalized convulsive seizures. Bumetanide (0.3 mg/kg) alone or in combination with phenobarbital (15 or 30 mg/kg) exerted no significant effect on seizure occurrence. SIGNIFICANCE The data demonstrate that bumetanide does not increase the efficacy of phenobarbital in a model of birth asphyxia, which is consistent with the negative data of the recent human trial. The translational data obtained with the novel rat model of birth asphyxia indicate that it is a useful tool to evaluate novel treatments for neonatal seizures.
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Affiliation(s)
- Marie Johne
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Kerstin Römermann
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
| | - Philip Hampel
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Björn Gailus
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Wiebke Theilmann
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
| | - Tommi Ala-Kurikka
- Molecular and Integrative Biosciences and Neuroscience Center (HiLIFE), University of Helsinki, Helsinki, Finland
| | - Kai Kaila
- Molecular and Integrative Biosciences and Neuroscience Center (HiLIFE), University of Helsinki, Helsinki, Finland
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
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17
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Koumangoye R, Bastarache L, Delpire E. NKCC1: Newly Found as a Human Disease-Causing Ion Transporter. FUNCTION 2020; 2:zqaa028. [PMID: 33345190 PMCID: PMC7727275 DOI: 10.1093/function/zqaa028] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/28/2020] [Accepted: 10/30/2020] [Indexed: 01/06/2023] Open
Abstract
Among the electroneutral Na+-dependent chloride transporters, NKCC1 had until now evaded identification as a protein causing human diseases. The closely related SLC12A transporters, NKCC2 and NCC have been identified some 25 years ago as responsible for Bartter and Gitelman syndromes: two renal-dependent salt wasting disorders. Absence of disease was most surprising since the NKCC1 knockout mouse was shown in 1999 to be viable, albeit with a wide range of deleterious phenotypes. Here we summarize the work of the past 5 years that introduced us to clinical cases involving NKCC1. The most striking cases are of 3 children with inherited mutations, who have complete absence of NKCC1 expression. These cases establish that lack of NKCC1 causes deafness; CFTR-like secretory defects with mucus accumulation in lung and intestine; severe xerostomia, hypotonia, dysmorphic facial features, and severe neurodevelopmental disorder. Another intriguing case is of a patient with a dominant deleterious SLC12A2 allele. This de novo mutation introduced a premature stop codon leading to a truncated protein. This mutant transporter seems to exert dominant-negative effect on wild-type transporter only in epithelial cells. The patient who suffers from lung, bladder, intestine, pancreas, and multiple endocrine abnormalities has, however, normal hearing and cognition. Finally, new reports substantiate the haploinsufficiency prediction of the SLC12A2 gene. Cases with single allele mutations in SLC12A2 have been linked to hearing loss and neurodevelopmental disorders.
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Affiliation(s)
- Rainelli Koumangoye
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Lisa Bastarache
- Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Eric Delpire
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA,Corresponding author. E-mail:
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18
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Theilmann W, Brandt C, Bohnhorst B, Winstroth AM, Das AM, Gramer M, Kipper A, Kalesse M, Löscher W. Hydrolytic biotransformation of the bumetanide ester prodrug DIMAEB to bumetanide by esterases in neonatal human and rat serum and neonatal rat brain-A new treatment strategy for neonatal seizures? Epilepsia 2020; 62:269-278. [PMID: 33140458 DOI: 10.1111/epi.16746] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/06/2020] [Accepted: 10/08/2020] [Indexed: 01/08/2023]
Abstract
OBJECTIVES The loop diuretic bumetanide has been proposed previously as an adjunct treatment for neonatal seizures because bumetanide is thought to potentiate the action of γ-aminobutyric acid (GABA)ergic drugs such as phenobarbital by preventing abnormal intracellular accumulation of chloride and the subsequent "GABA shift." However, a clinical trial in neonates failed to demonstrate such a synergistic effect of bumetanide, most likely because this drug only poorly penetrates into the brain. This prompted us to develop lipophilic prodrugs of bumetanide, such as the N,N-dimethylaminoethyl ester of bumetanide (DIMAEB), which rapidly enter the brain where they are hydrolyzed by esterases to the parent compound, as demonstrated previously by us in adult rodents. However, it is not known whether esterase activity in neonates is sufficient to hydrolyze ester prodrugs such as DIMAEB. METHODS In the present study, we examined whether esterases in neonatal serum of healthy term infants are capable of hydrolyzing DIMAEB to bumetanide and whether this activity is different from the serum of adults. Furthermore, to extrapolate the findings to brain tissue, we performed experiments with brain tissue and serum of neonatal and adult rats. RESULTS Serum from 1- to 2-day-old infants was capable of hydrolyzing DIMAEB to bumetanide at a rate similar to that of serum from adult individuals. Similarly, serum and brain tissue of neonatal rats rapidly hydrolyzed DIMAEB to bumetanide. SIGNIFICANCE These data provide a prerequisite for further evaluating the potential of bumetanide prodrugs as add-on therapy to phenobarbital and other antiseizure drugs as a new strategy for improving pharmacotherapy of neonatal seizures.
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Affiliation(s)
- Wiebke Theilmann
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Claudia Brandt
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Bettina Bohnhorst
- Department of Pediatric Pulmonology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
| | - Anne-Mieke Winstroth
- Department of Pediatric Pulmonology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
| | - Anibh Martin Das
- Clinic for Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| | - Martina Gramer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Andi Kipper
- Institute for Organic Chemistry, Leibniz Universität Hannover, Hannover, Germany
| | - Markus Kalesse
- Institute for Organic Chemistry, Leibniz Universität Hannover, Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience Hannover, Hannover, Germany
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19
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Yang XL, Zeng ML, Shao L, Jiang GT, Cheng JJ, Chen TX, Han S, Yin J, Liu WH, He XH, Peng BW. NFAT5 and HIF-1α Coordinate to Regulate NKCC1 Expression in Hippocampal Neurons After Hypoxia-Ischemia. Front Cell Dev Biol 2019; 7:339. [PMID: 31921851 PMCID: PMC6923656 DOI: 10.3389/fcell.2019.00339] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 11/29/2019] [Indexed: 12/22/2022] Open
Abstract
Hypoxic-ischemic encephalopathy (HIE) is a serious birth complication with severe long-term sequelae such as cerebral palsy, epilepsy and cognitive disabilities. Na+-K+-2Cl– cotransporters 1 (NKCC1) is dramatically upregulated after hypoxia-ischemia (HI), which aggravates brain edema and brain damage. Clinically, an NKCC1-specific inhibitor, bumetanide, is used to treat diseases related to aberrant NKCC1 expression, but the underlying mechanism of aberrant NKCC1 expression has rarely been studied in HIE. In this study, the cooperative effect of hypoxia-inducible factor-1α (HIF-1α) and nuclear factor of activated T cells 5 (NFAT5) on NKCC1 expression was explored in hippocampal neurons under hypoxic conditions. HI increased HIF-1α nuclear localization and transcriptional activity, and pharmacological inhibition of the HIF-1α transcription activity or mutation of hypoxia responsive element (HRE) motifs recovered the hypoxia-induced aberrant expression and promoter activity of NKCC1. In contrast, oxygen–glucose deprivation (OGD)-induced downregulation of NFAT5 expression was reversed by treating with hypertonic saline, which ameliorated aberrant NKCC1 expression. More importantly, knocking down NFAT5 or mutation of the tonicity enhancer element (TonE) stimulated NKCC1 expression and promoter activity under normal physiological conditions. The positive regulation of NKCC1 by HIF-1α and the negative regulation of NKCC1 by NFAT5 may serve to maintain NKCC1 expression levels, which may shed light on the transcription regulation of NKCC1 in hippocampal neurons after hypoxia.
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Affiliation(s)
- Xing-Liang Yang
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Meng-Liu Zeng
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Lin Shao
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Guang-Tong Jiang
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Jing-Jing Cheng
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Tao-Xiang Chen
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Song Han
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Jun Yin
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Wan-Hong Liu
- Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Xiao-Hua He
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Bi-Wen Peng
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, China
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20
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Xu J, Xu M, Wang Y, Mathena RP, Wen J, Zhang P, Furmanski O, Mintz CD. Anesthetics disrupt growth cone guidance cue sensing through actions on the GABA A α2 receptor mediated by the immature chloride gradient. Neurotoxicol Teratol 2019; 74:106812. [PMID: 31251980 DOI: 10.1016/j.ntt.2019.106812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/25/2019] [Accepted: 06/24/2019] [Indexed: 01/17/2023]
Abstract
BACKGROUND General anesthetics (GAs) may exert harmful effects on the developing brain by disrupting neuronal circuit formation. Anesthetics that act on γ-aminobutyric acid (GABA) receptors can interfere with axonal growth cone guidance, a critical process in the assembly of neuronal circuitry. Here we investigate the mechanism by which isoflurane prevents sensing of the repulsive guidance cue, Semaphorin 3A (Sema3A). METHODS Growth cone sensing was assayed by measuring growth cone collapse in dissociated neocortical cultures exposed to recombinant Sema3A in the presence or absence of isoflurane and/or a panel of reagents with specific actions on components of the GABA receptor and chloride ion systems. RESULTS Isoflurane exposure prevents Sema3A induced growth cone collapse. A GABAA α2 specific agonist replicates this effect (36.83 ± 3.417% vs 70.82 ± 2.941%, in the Sema3A induced control group, p < 0.0001), but an α1-specific agonist does not. Both a Na-K-Cl cotransporter 1 antagonism (bumetanide, BUM) and a chloride ionophore (IONO) prevent isoflurane from disrupting growth cone sensing of Sema3A. (65.67 ± 3.775% in Iso + BUM group vs 67.45 ± 3.624% in Sema3A induced control group, 65.34 ± 1.678% in Iso + IONO group vs 68.71 ± 2.071% in Sema3A induced control group, no significant difference) (n = 96 growth cones per group). CONCLUSION Our data suggest that the effects of isoflurane on growth cone sensing are mediated by the α2 subunit of the GABAA receptor and also that they are dependent on the developmental chloride gradient, in which Cl- exhibits a depolarizing effect. These findings provide a rationale for why immature neurons are particularly susceptible to anesthetic toxicity.
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Affiliation(s)
- Jing Xu
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi, 710004, China; Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Michael Xu
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - YuChia Wang
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - R Paige Mathena
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jieqiong Wen
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi, 710004, China; Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Pengbo Zhang
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi, 710004, China
| | - Orion Furmanski
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - C David Mintz
- Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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21
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Hirst JJ, Palliser HK, Shaw JC, Crombie G, Walker DW, Zakar T. Birth and Neonatal Transition in the Guinea Pig: Experimental Approaches to Prevent Preterm Birth and Protect the Premature Fetus. Front Physiol 2018; 9:1802. [PMID: 30618814 PMCID: PMC6297273 DOI: 10.3389/fphys.2018.01802] [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] [Received: 09/28/2018] [Accepted: 11/29/2018] [Indexed: 11/13/2022] Open
Abstract
The guinea pig (Cavia porcellus) displays many features of gestational physiology that makes it the most translationally relevant rodent species. Progesterone production undergoes a luteal to placental shift as in human pregnancy with levels rising during gestation and with labor and delivery occurring without a precipitous decline in maternal progesterone levels. In contrast to other laboratory rodents, labor in guinea pigs is triggered by a functional progesterone withdrawal, which involves the loss of uterine sensitivity to progesterone like in women. In both species the amnion membrane is a major source of labor-inducing prostaglandins, which promote functional progesterone withdrawal by modifying myometrial progesterone receptor expression. These similar features appear to result from convergent evolution rather than closer evolutionally relationship to primates compared to other rodents. Nevertheless, the similarities in the production, metabolism and actions of progesterone and prostaglandins allow information gained in pregnant guinea pigs to be extended to pregnant women with confidence. This includes exploring the effects of pregnancy complications including growth restriction and the mechanisms by which stressful conditions increase the incidence of preterm labor. The relatively long gestation of the guinea pig and the maturity of the pups at birth particularly in brain development means that a greater proportion of brain development happens in utero. This allows adverse intrauterine conditions to make a sustained impact on the developing brain like in compromised human pregnancies. In addition, the brain is exposed to a protective neurosteroid environment in utero, which has been suggested to promote development in the guinea pig and the human. Moreover, in utero stresses that have been shown to adversely affect long term neurobehavioral outcomes in clinical studies, can be modeled successfully in guinea pigs. Overall, these parallels to the human have led to increasing interest in the guinea pig for translational studies of treatments and therapies that potentially improve outcomes following adverse events in pregnancy and after preterm birth.
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Affiliation(s)
- Jonathan J Hirst
- Mothers and Babies Research Centre, Hunter Medical Research Institute, Newcastle, NSW, Australia.,School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, NSW, Australia
| | - Hannah K Palliser
- Mothers and Babies Research Centre, Hunter Medical Research Institute, Newcastle, NSW, Australia.,School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, NSW, Australia
| | - Julia C Shaw
- Mothers and Babies Research Centre, Hunter Medical Research Institute, Newcastle, NSW, Australia.,School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, NSW, Australia
| | - Gabrielle Crombie
- Mothers and Babies Research Centre, Hunter Medical Research Institute, Newcastle, NSW, Australia.,School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, NSW, Australia
| | - David W Walker
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, Australia
| | - Tamas Zakar
- Mothers and Babies Research Centre, Hunter Medical Research Institute, Newcastle, NSW, Australia.,School of Medicine and Public Health, University of Newcastle, Newcastle, NSW, Australia
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22
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Rahmanzadeh R, Mehrabi S, Barati M, Ahmadi M, Golab F, Kazmi S, Joghataei MT, Seifi M, Gholipourmalekabadi M. Effect of Co-administration of Bumetanide and Phenobarbital on Seizure Attacks in Temporal Lobe Epilepsy. Basic Clin Neurosci 2018; 9:408-416. [PMID: 30719255 PMCID: PMC6359685 DOI: 10.32598/bcn.9.6.408] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Revised: 10/20/2016] [Accepted: 01/20/2018] [Indexed: 01/14/2023] Open
Abstract
Introduction: The resistance of temporal lobe epilepsy to classic drugs is thought to be due to disruption in the excitation/inhibition of this pathway. Two chloride transporters, NKCC1 and KCC2, are expressed differently for the excitatory state of Gamma-Amino Butyric Acid (GABA). The present study explored the effect of bumetanide as a selective NKCC1 inhibitor either alone or in combination with the phenobarbital in the pilocarpine model of epilepsy. Methods: An animal model of Status Epilepticus (SE) was induced with pilocarpine in Wistar male rats followed by phenobarbital and or bumetanide or saline administration for 45 days after the induction of SE by Intraperitoneal (IP) injection. The rats were monitored, their behavior was recorded, and after 24 hours they were sacrificed to study the expression of NKCC1 and KCC2 using real time PCR. Results: The data showed that the effects of a combination of bumetanide with phenobarbital on frequency rate and duration of seizure attack were more than those of the phenobarbital alone. In addition, in the bumetanide and combined treatment groups, NKCC1 expression decreased significantly, compared with untreated epileptic animals. A delayed decrement in NKCC1/KCC2 expression ratio after bumetanide application was also observed. Conclusion: The combination of bumetanide with phenobarbital increases the inhibition of SE and maximizes the potential of GABA signaling pathway, and can be considered as an effective therapeutic strategy in patients with epilepsy.
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Affiliation(s)
- Reza Rahmanzadeh
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Soraya Mehrabi
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mahmood Barati
- Department of Biotechnology, School of Allied Medicine, Iran University of Medical Science, Tehran, Iran
| | - Milad Ahmadi
- Shefa Neuroscience Research Center, Tehran, Iran
| | - Fereshteh Golab
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Sareh Kazmi
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Taghi Joghataei
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran.,Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Morteza Seifi
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Mazaher Gholipourmalekabadi
- Department of Tissue Engineering & Regenerative Medicine, School of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran
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23
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Carter BM, Sullivan BJ, Landers JR, Kadam SD. Dose-dependent reversal of KCC2 hypofunction and phenobarbital-resistant neonatal seizures by ANA12. Sci Rep 2018; 8:11987. [PMID: 30097625 PMCID: PMC6086916 DOI: 10.1038/s41598-018-30486-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 07/31/2018] [Indexed: 01/22/2023] Open
Abstract
Neonatal seizures have an incidence of 3.5 per 1000 newborns; while hypoxic-ischemic encephalopathy (HIE) accounts for 50-60% of cases, half are resistant to 1st-line anti-seizure drugs such as phenobarbital (PB). Tyrosine receptor kinase B (TrkB) activation following ischemic injury is known to increase neuronal excitability by downregulation of K-Cl co-transporter 2 (KCC2); a neuronal chloride (Cl-) co-transporter. In this study, three graded doses of ANA12, a small-molecule selective TrkB antagonist, were tested in CD1 mice at P7 and P10 following induction of neonatal ischemia by a unilateral carotid ligation. The PB loading dose remained the same in all treatment groups at both ages. Evaluation criteria for the anti-seizure efficacy of ANA12 were: (1) quantitative electroencephalographic (EEG) seizure burden and power, (2) rescue of post-ischemic KCC2 and pKCC2-S940 downregulation and (3) reversal of TrkB pathway activation following ischemia. ANA12 significantly rescued PB resistant seizures in a dose-dependent manner at P7 and improved PB efficacy at P10. Additionally, female pups responded better to lower doses of ANA12 compared to males. ANA12 significantly reversed post-ischemic KCC2 downregulation and TrkB pathway activation at P7 when PB alone was inefficacious. Rescuing KCC2 hypofunction may be critical for preventing emergence of refractory seizures.
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Affiliation(s)
- B M Carter
- Neuroscience Laboratory, Hugo Moser Research Institute at Kennedy Krieger, Baltimore, MD, USA
| | - B J Sullivan
- Neuroscience Laboratory, Hugo Moser Research Institute at Kennedy Krieger, Baltimore, MD, USA
| | - J R Landers
- Neuroscience Laboratory, Hugo Moser Research Institute at Kennedy Krieger, Baltimore, MD, USA
| | - S D Kadam
- Neuroscience Laboratory, Hugo Moser Research Institute at Kennedy Krieger, Baltimore, MD, USA.
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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24
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Ko MC, Lee MC, Tang TH, Amstislavskaya TG, Tikhonova MA, Yang YL, Lu KT. Bumetanide blocks the acquisition of conditioned fear in adult rats. Br J Pharmacol 2018; 175:1580-1589. [PMID: 29235092 PMCID: PMC5913399 DOI: 10.1111/bph.14125] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 09/05/2017] [Accepted: 09/08/2017] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Bumetanide has anxiolytic effects in rat models of conditioned fear. As a loop diuretic, bumetanide blocks cation-chloride co-transport and this property may allow bumetanide to act as an anxiolytic by modulating GABAergic synaptic transmission in the CNS. Its potential for the treatment of anxiety disorders deserves further investigation. In this study, we evaluated the possible involvement of the basolateral nucleus of the amygdala in the anxiolytic effect of bumetanide. EXPERIMENTAL APPROACH Brain slices were prepared from Wistar rats. extracellular recording, stereotaxic surgery, fear-potentiated startle response, locomotor activity monitoring and Western blotting were applied in this study. KEY RESULTS Systemic administration of bumetanide (15.2 mg·kg-1 , i.v.), 30 min prior to fear conditioning, significantly inhibited the acquisition of the fear-potentiated startle response. Phosphorylation of ERK in the basolateral nucleus of amygdala was reduced after bumetanide administration. In addition, suprafusion of bumetanide (5 or 10 μM) attenuated long-term potentiation in the amygdala in a dose-dependent manner. Intra-amygdala infusion of bumetanide, 15 min prior to fear conditioning, also blocked the acquisition of the fear-potentiated startle response. Finally, the possible off-target effect of bumetanide on conditioned fear was excluded by side-by-side control experiments. CONCLUSIONS AND IMPLICATIONS These results suggest the basolateral nucleus of amygdala plays a critical role in the anxiolytic effects of bumetanide.
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Affiliation(s)
- Meng-Chang Ko
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Ming-Chung Lee
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Tso-Hao Tang
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Tamara G Amstislavskaya
- Laboratory of Experimental Models of Neurodegenerative Processes, Federal State Budgetary Scientific Institution "Scientific Research Institute of Physiology and Basic Medicine" (SRIPhBM), Novosibirsk, Russia
- Novosibirsk State University, Novosibirsk, Russia
| | - Maria A Tikhonova
- Laboratory of Experimental Models of Neurodegenerative Processes, Federal State Budgetary Scientific Institution "Scientific Research Institute of Physiology and Basic Medicine" (SRIPhBM), Novosibirsk, Russia
- Novosibirsk State University, Novosibirsk, Russia
| | - Yi-Ling Yang
- Department of Biochemical Science and Technology, National Chiayi University, Chiayi, Taiwan
| | - Kwok-Tung Lu
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
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25
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Menzikov S. Biochemical properties of the sensitivity to GABA Aergic ligands, Cl -/HCO 3--ATPase isolated from fish (Cyprinus carpio) olfactory mucosa and brain. FISH PHYSIOLOGY AND BIOCHEMISTRY 2018; 44:583-597. [PMID: 29218440 DOI: 10.1007/s10695-017-0455-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 11/30/2017] [Indexed: 06/07/2023]
Abstract
This paper presents a comparative study of the roles of Cl- and HCO3- in the functioning of the GABAAR-associated Cl-/HCO3--ATPase of the plasma membranes of the olfactory sensory neurons (OSNs) and mature brain neurons (MBNs) of fish. The ATPase activity of OSNs and its dephosphorylation were increased twofold by Cl-(15-30 mmol l-1), whereas the enzyme from MBNs was not significantly affected by Cl-. By contrast, HCO3-(15-30 mmol l-1) significantly activated the MBN enzyme and its dephosphorylation, but had no effect on the OSN ATPase. The maximum ATPase activity and protein dephosphorylation was observed in the presence of both Cl-(15 mmol l-1)/HCO3-(27 mmol l-1) and these activities were inhibited in the presence of picrotoxin (100 μmol l-1), bumetanide (150 μmol l-1), and DIDS (1000 μmol l-1). SDS-PAGE revealed that ATPases purified from the neuronal membrane have a subunit with molecular mass of ~ 56 kDa that binds [3H]muscimol and [3H]flunitrazepam. Direct phosphorylation of the enzymes in the presence of ATP-γ-32P and Mg2+, as well as Cl-/HCO3- sensitive dephosphorylation, is also associated with this 56 kDa peptide. Both preparations also showed one subunit with molecular mass 56 kDa that was immunoreactive with GABAAR β3 subunit. The use of a fluorescent dye for Cl- demonstrated that HCO3-(27 mmol l-1) causes a twofold increase in Cl- influx into proteoliposomes containing reconstituted ATPases from MBNs, but HCO3- had no effect on the reconstituted enzyme from OSNs. These data are the first to demonstrate a differential effect of Cl- and HCO3- in the regulation of the Cl-/HCO3--ATPases functioning in neurons with different specializations.
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Affiliation(s)
- Sergey Menzikov
- Department Russian Academy of Science, Institute of General Pathology and Pathophysiology, 8, Baltiyskaya st., Moscow, Russia, 125315.
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26
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Ye H, Kaszuba S. Inhibitory or excitatory? Optogenetic interrogation of the functional roles of GABAergic interneurons in epileptogenesis. J Biomed Sci 2017; 24:93. [PMID: 29202749 PMCID: PMC5715558 DOI: 10.1186/s12929-017-0399-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 11/28/2017] [Indexed: 01/22/2023] Open
Abstract
Alteration in the excitatory/inhibitory neuronal balance is believed to be the underlying mechanism of epileptogenesis. Based on this theory, GABAergic interneurons are regarded as the primary inhibitory neurons, whose failure of action permits hyperactivity in the epileptic circuitry. As a consequence, optogenetic excitation of GABAergic interneurons is widely used for seizure suppression. However, recent evidence argues for the context-dependent, possibly “excitatory” roles that GABAergic cells play in epileptic circuitry. We reviewed current optogenetic approaches that target the “inhibitory” roles of GABAergic interneurons for seizure control. We also reviewed interesting evidence that supports the “excitatory” roles of GABAergic interneurons in epileptogenesis. GABAergic interneurons can provide excitatory effects to the epileptic circuits via several distinct neurological mechanisms. (1) GABAergic interneurons can excite postsynaptic neurons, due to the raised reversal potential of GABA receptors in the postsynaptic cells. (2) Continuous activity in GABAergic interneurons could lead to transient GABA depletion, which prevents their inhibitory effect on pyramidal cells. (3) GABAergic interneurons can synchronize network activity during seizure. (4) Some GABAergic interneurons inhibit other interneurons, causing disinhibition of pyramidal neurons and network hyperexcitability. The dynamic, context-dependent role that GABAergic interneurons play in seizure requires further investigation of their functions at single cell and circuitry level. New optogenetic protocols that target GABAergic inhibition should be explored for seizure suppression.
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Affiliation(s)
- Hui Ye
- Department of Biology, Loyola University Chicago, Quinlan Life Sciences Education and Research Center, 1032 W. Sheridan Rd, Chicago, IL, 60660, USA.
| | - Stephanie Kaszuba
- Department of Biology, Loyola University Chicago, Quinlan Life Sciences Education and Research Center, 1032 W. Sheridan Rd, Chicago, IL, 60660, USA
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27
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Yozawitz E, Stacey A, Pressler RM. Pharmacotherapy for Seizures in Neonates with Hypoxic Ischemic Encephalopathy. Paediatr Drugs 2017; 19:553-567. [PMID: 28770451 DOI: 10.1007/s40272-017-0250-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Seizures are common in neonates with moderate and severe hypoxic ischemic encephalopathy (HIE) and are associated with worse outcomes, independent of HIE severity. In contrast to adults and older children, no new drugs have been licensed for treatment of neonatal seizures over the last 50 years, because of a lack of controlled clinical trials. Hence, many antiseizure medications licensed in older children and adults are used off-label for neonatal seizure, which is associated with potential risks of adverse effects during a period when the brain is particularly vulnerable. Phenobarbital is worldwide the first-line drug and is considered standard of care, although there is a limited evidence base for its efficacy. Second-line agents include phenytoin, benzodiazepines, levetiracetam, and lidocaine. These drugs are discussed in more detail along with two emerging drugs (bumetanide and topiramate). More safety, pharmacokinetic, and efficacy data are needed from well-designed clinical trials to develop safe and effective antiseizure regimes for the treatment of neonatal seizures in HIE.
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Affiliation(s)
- Elissa Yozawitz
- Department of Neurology and Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Arthur Stacey
- UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Ronit M Pressler
- Department of Clinical Neurophysiology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, Great Ormond Street, London, WC1N 3JH, UK. .,Clinical Neurosciences, UCL- Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK.
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28
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Kambli L, Bhatt LK, Oza M, Prabhavalkar K. Novel therapeutic targets for epilepsy intervention. Seizure 2017; 51:27-34. [DOI: 10.1016/j.seizure.2017.07.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 07/23/2017] [Accepted: 07/24/2017] [Indexed: 12/11/2022] Open
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Torolira D, Suchomelova L, Wasterlain CG, Niquet J. Phenobarbital and midazolam increase neonatal seizure-associated neuronal injury. Ann Neurol 2017; 82:115-120. [PMID: 28556259 DOI: 10.1002/ana.24967] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 05/24/2017] [Accepted: 05/24/2017] [Indexed: 02/01/2023]
Abstract
Status epilepticus is common in neonates and infants, and is associated with neuronal injury and adverse developmental outcomes. γ-Aminobutyric acidergic (GABAergic) drugs, the standard treatment for neonatal seizures, can have excitatory effects in the neonatal brain, which may worsen the seizures and their effects. Using a recently developed model of status epilepticus in postnatal day 7 rat pups that results in widespread neuronal injury, we found that the GABAA agonists phenobarbital and midazolam significantly increased status epilepticus-associated neuronal injury in various brain regions. Our results suggest that more research is needed into the possible deleterious effects of GABAergic drugs on neonatal seizures and on excitotoxic neuronal injury in the immature brain. Ann Neurol 2017;82:115-120.
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Affiliation(s)
- Daniel Torolira
- Epilepsy Research Laboratory (151), Veterans Affairs Greater Los Angeles Healthcare System
| | - Lucie Suchomelova
- Epilepsy Research Laboratory (151), Veterans Affairs Greater Los Angeles Healthcare System
| | - Claude G Wasterlain
- Epilepsy Research Laboratory (151), Veterans Affairs Greater Los Angeles Healthcare System.,Department of Neurology.,Brain Research Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Jerome Niquet
- Epilepsy Research Laboratory (151), Veterans Affairs Greater Los Angeles Healthcare System.,Department of Neurology
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30
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Zhang J, Pu H, Zhang H, Wei Z, Jiang X, Xu M, Zhang L, Zhang W, Liu J, Meng H, Stetler RA, Sun D, Chen J, Gao Y, Chen L. Inhibition of Na +-K +-2Cl - cotransporter attenuates blood-brain-barrier disruption in a mouse model of traumatic brain injury. Neurochem Int 2017; 111:23-31. [PMID: 28577991 DOI: 10.1016/j.neuint.2017.05.020] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 05/21/2017] [Accepted: 05/30/2017] [Indexed: 02/06/2023]
Abstract
Traumatic brain injury (TBI) can lead to long-term motor and cognitive dysfunction, which can be at least partly attributed to blood-brain barrier (BBB) disruption. The mechanisms underlying post-TBI BBB disruption, however, are poorly understood thus far. Na+-K+-2Cl- cotransporter isoform 1 (NKCC1) is a universally expressed ion transporter that maintains intracellular ion homeostasis by increasing intracellular K+ and Cl-. Having been characterized in stroke models, NKCC1 is activated in various cell types in the ischemic brain, and is thought to mediate BBB disruption, brain edema, and neuronal cell death. In this study, we tested the hypothesis that inhibition of NKCC1 may improve neurological outcomes via protecting against BBB disruption in a TBI mouse model. Adult male C57BL/6 J mice or NKCC1 deficient mice were subjected to controlled cortical impact (CCI). As an alternative to the genetic-based NKCC1 depletion, bumetanide, a selective NKCC1 inhibitor, was administrated (25 mg/kg, i.p.) 15 min after CCI and then every 6 h up to 48 h. Short-term sensorimotor function recovery was determined by rotarod, cylinder test, grid walking and foot fault test. BBB integrity was examined at 48 h post-CCI by measuring Evans blue extravasation, brain water content, and expression levels of tight junction proteins. Our results revealed that administration of bumetanide or genetic depletion of NKCC1 improved short-term neurological recovery against TBI. Bumetanide treatment markedly decreased brain water content and BBB leakage, correlated with reduction of MMP-9 expression and preventing the degradation of tight junction proteins. These findings suggest an important role of NKCC1 activation in mediating BBB disruption after TBI. Thus, NKCC1 inhibition may offer the potential for improving neurological outcomes in clinical TBI.
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Affiliation(s)
- Jun Zhang
- Department of Neurosurgery, General Hospital of PLA, Beijing, China
| | - Hongjian Pu
- State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, China; Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Haiyue Zhang
- Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Zhishuo Wei
- Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Xiaoyan Jiang
- State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, China; Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Mingyue Xu
- State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, China; Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Lili Zhang
- Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Wenting Zhang
- State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, China
| | - Jialin Liu
- Department of Neurosurgery, General Hospital of PLA, Beijing, China
| | - Hengxing Meng
- Department of Neurosurgery, General Hospital of PLA, Beijing, China
| | - R Anne Stetler
- Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Dandan Sun
- Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Jun Chen
- State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, China; Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Yanqin Gao
- State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, China; Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh School of Medicine, Pittsburgh, USA.
| | - Ling Chen
- Department of Neurosurgery, General Hospital of PLA, Beijing, China.
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31
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Wang XX, Li YH, Gong HQ, Liang PJ, Zhang PM, Lu QC. The Subiculum: A Potential Site of Ictogenesis in a Neonatal Seizure Model. Front Neurol 2017; 8:147. [PMID: 28473802 PMCID: PMC5397469 DOI: 10.3389/fneur.2017.00147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 03/31/2017] [Indexed: 01/03/2023] Open
Abstract
Studies have reported that the subiculum is one origin of interictal-like discharges in adult patients with temporal lobe epilepsy; however, whether the subiculum represents a site of ictogenesis for neonatal seizures remains unclear. In this study, multi-electrode recording techniques were used to record epileptiform discharges induced by low-Mg2+ or high-K+ artificial cerebrospinal fluid in neonatal mouse hippocampal slices, and the spatiotemporal dynamics of the epileptiform discharges were analyzed. The Na+–K+–2Cl− cotransporter 1 (NKCC1) blocker, bumetanide, was applied to test its effect upon epileptiform discharges in low-Mg2+ model. The effect of N-methyl-d-aspartate receptors (NMDARs) antagonist, d-AP5, upon the epileptiform discharges in high-K+ model was examined. We found that the neonatal subiculum not only relayed epileptiform discharges emanating from the hippocampus proper (HP) but also initiated epileptiform discharges (interictal- and ictal-like discharges) independently. The latency to onset of the first epileptiform discharge initiated in the subiculum was similar to that initiated in the HP. Bumetanide efficiently blocked seizures in the neonatal HP, but was less effectively in suppressing seizures initiated in the subiculum. In high-K+ model, d-AP5 was more effective in blocking seizures initiated in the subiculum than that initiated in the HP. Furthermore, Western blotting analysis showed that NKCC1 expression was lower in the subiculum than that in the HP, whereas the expression of NMDAR subunits, NR2A and NR2B, was higher in the subiculum than that in the HP. Our results revealed that the subiculum was a potential site of ictogenesis in neonatal seizures and possessed similar seizure susceptibility to the HP. GABAergic excitation resulting from NKCC1 may play a less dominant role during ictogenesis in the subiculum than that in the HP. The subicular ictogenesis may be related to the glutamatergic excitation mediated by NMDARs.
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Affiliation(s)
- Xin-Xin Wang
- Department of Neurology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yong-Hua Li
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Hai-Qing Gong
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Pei-Ji Liang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Pu-Ming Zhang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Qin-Chi Lu
- Department of Neurology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
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32
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Xu WS, Sun X, Song CG, Mu XP, Ma WP, Zhang XH, Zhao CS. Bumetanide promotes neural precursor cell regeneration and dendritic development in the hippocampal dentate gyrus in the chronic stage of cerebral ischemia. Neural Regen Res 2016; 11:745-51. [PMID: 27335557 PMCID: PMC4904464 DOI: 10.4103/1673-5374.182700] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Bumetanide has been shown to lessen cerebral edema and reduce the infarct area in the acute stage of cerebral ischemia. Few studies focus on the effects of bumetanide on neuroprotection and neurogenesis in the chronic stage of cerebral ischemia. We established a rat model of cerebral ischemia by injecting endothelin-1 in the left cortical motor area and left corpus striatum. Seven days later, bumetanide 200 µg/kg/day was injected into the lateral ventricle for 21 consecutive days with a mini-osmotic pump. Results demonstrated that the number of neuroblasts cells and the total length of dendrites increased, escape latency reduced, and the number of platform crossings increased in the rat hippocampal dentate gyrus in the chronic stage of cerebral ischemia. These findings suggest that bumetanide promoted neural precursor cell regeneration, dendritic development and the recovery of cognitive function, and protected brain tissue in the chronic stage of ischemia.
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Affiliation(s)
- Wang-Shu Xu
- Department of Neurology, First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, China; Neuroinfection and Neuroimmunology Center, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Xuan Sun
- Department of Interventional Neuroradiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Cheng-Guang Song
- Department of Neurology, First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, China; Department of Neurology, Benxi Central Hospital of China Medical University, Benxi, Liaoning Province, China
| | - Xiao-Peng Mu
- Department of Neurology, First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, China
| | - Wen-Ping Ma
- Department of Medical Genetics, School of Basic Medicine, Peking University, Beijing, China
| | - Xing-Hu Zhang
- Neuroinfection and Neuroimmunology Center, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Chuan-Sheng Zhao
- Department of Neurology, First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, China
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33
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Kaur H, Kumar B, Medhi B. Antiepileptic drugs in development pipeline: A recent update. eNeurologicalSci 2016; 4:42-51. [PMID: 29430548 PMCID: PMC5803110 DOI: 10.1016/j.ensci.2016.06.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 04/16/2016] [Accepted: 06/15/2016] [Indexed: 12/18/2022] Open
Abstract
Epilepsy is the most common neurological disorder which significantly affects the quality of life and poses a health as well as economic burden on society. Epilepsy affects approximately 70 million people in the world. The present article reviews the scientific rationale, brief pathophysiology of epilepsy and newer antiepileptic drugs which are presently under clinical development. We have searched the investigational drugs using the key words ‘antiepileptic drugs,’ ‘epilepsy,’ ‘Phase I,’ ‘Phase II’ and ‘Phase III’ in American clinical trial registers (clinicaltrials.gov), the relevant published articles using National Library of Medicine's PubMed database, company websites and supplemented results with a manual search of cross-references and conference abstracts. This review provides a brief description about the antiepileptic drugs which are targeting different mechanisms and the clinical development status of these drugs. Besides the presence of old as well as new AEDs, still there is a need of new drugs or the modified version of old drugs in order to make affected people free of seizures. An optimistic approach should be used to translate the success of preclinical testing to clinical practice. There is an urgent need to improve animal models and to explore new targets with better understanding in order to develop the novel drugs with more efficacy and safety. This review primarily focused on antiepileptic drugs under clinical development. The more realistic approach is needed to discover and develop the novel antiepileptic drugs. Modification of conventional drugs or search of newer targets can lead to development of promising antiepileptic drugs. To develop more efficacious and safe drugs for treatment of epilepsy and refractory seizures There are a number of novel antiepileptic compounds which are under various stages of drug development.
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Affiliation(s)
- Harjeet Kaur
- Department of Pharmacology, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India
| | - Baldeep Kumar
- Department of Pharmacology, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India
| | - Bikash Medhi
- Department of Pharmacology, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India
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34
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Du C, Zheng F, Wang X. Exploring novel AEDs from drugs used for treatment of non-epileptic disorders. Expert Rev Neurother 2016; 16:449-61. [PMID: 27010915 DOI: 10.1586/14737175.2016.1158101] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Epilepsy is a chronic neurological disease. Although many anti-epileptic drugs (AEDs) have been developed for clinical use, they have no effect on 20-30% of patients and do not generally prevent epileptogenesis. Because of the long development cycle for new AEDs and the high cost, increasing efforts are being made to find anti-epileptic effects among drugs that are already listed for the treatment of other diseases and repurpose them as potential anti-epileptic treatments. Here, we review the progress that has been made in this field as a result of animal and clinical trials of drugs such as rapamycin, everolimus, losartan, celecoxib, bumetanide and other non-epileptic drugs. These drugs can prevent the epileptogenesis, reduce the epileptic pathological changes, and even be used to treat intractable epilepsy. Their mechanisms of action are completely different from those of existing AEDs, prompting researchers to change their perspectives in the search for new AEDs.
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Affiliation(s)
- Chao Du
- a Department of Neurology , The First Affiliated Hospital of Chongqing Medical University , Chongqing , China
| | - Fangshuo Zheng
- a Department of Neurology , The First Affiliated Hospital of Chongqing Medical University , Chongqing , China
| | - Xuenfeng Wang
- a Department of Neurology , The First Affiliated Hospital of Chongqing Medical University , Chongqing , China
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35
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Erker T, Brandt C, Töllner K, Schreppel P, Twele F, Schidlitzki A, Löscher W. The bumetanide prodrug BUM5, but not bumetanide, potentiates the antiseizure effect of phenobarbital in adult epileptic mice. Epilepsia 2016; 57:698-705. [PMID: 26921222 DOI: 10.1111/epi.13346] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/01/2016] [Indexed: 01/22/2023]
Abstract
OBJECTIVE The loop diuretic bumetanide has been reported to potentiate the antiseizure activity of phenobarbital in rodent models of neonatal seizures, most likely as a result of inhibition of the chloride importer Na-K-Cl cotransporter isoform 1 (NKCC1) in the brain. In view of the intractability of neonatal seizures, the preclinical findings prompted a clinical trial in neonates on bumetanide as an add-on to phenobarbital, which, however, had to be terminated because of ototoxicity and lack of efficacy. We have recently shown that bumetanide penetrates only poorly into the brain, so that we developed lipophilic prodrugs such as BUM5, the N,N-dimethylaminoethylester of bumetanide, which penetrate more easily into the brain and are converted to bumetanide. METHODS In the present study, we used a new strategy to test whether BUM5 is more potent than bumetanide in potentiating the antiseizure effect of phenobarbital. Adult mice were made epileptic by pilocarpine, and the antiseizure effects of bumetanide, BUM5, and phenobarbital alone or in combination were determined by the maximal electroshock seizure threshold test. RESULTS In nonepileptic mice, only phenobarbital exerted seizure threshold-increasing activity, and this was not potentiated by the NKCC1 inhibitors. In contrast, a marked potentiation of phenobarbital by BUM5, but not bumetanide, was determined in epileptic mice. SIGNIFICANCE Thus, bumetanide is not capable of potentiating phenobarbital's antiseizure effect in an adult mouse model, which, however, can be overcome by using the prodrug BUM5. These data substantiate that BUM5 is a promising tool compound for target validation and proof-of-concept studies on the role of NKCC1 in brain diseases.
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Affiliation(s)
- Thomas Erker
- Department of Medicinal Chemistry, University of Vienna, Vienna, Austria
| | - Claudia Brandt
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Kathrin Töllner
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Philipp Schreppel
- Department of Medicinal Chemistry, University of Vienna, Vienna, Austria
| | - Friederike Twele
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Alina Schidlitzki
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
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36
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Dhir A, Chopra K. On the anticonvulsant effect of allopregnanolone (a neurosteroid) in neonatal rats. Life Sci 2015; 143:202-8. [DOI: 10.1016/j.lfs.2015.09.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 08/03/2015] [Accepted: 09/15/2015] [Indexed: 11/29/2022]
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37
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Clark R, Blizzard C, Dickson T. Inhibitory dysfunction in amyotrophic lateral sclerosis: future therapeutic opportunities. Neurodegener Dis Manag 2015; 5:511-25. [DOI: 10.2217/nmt.15.49] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
In amyotrophic lateral sclerosis, motor neuron hyperexcitability and inhibitory dysfunction is emerging as a potential causative link in the dysfunction and degeneration of the motoneuronal circuitry that characterizes the disease. Interneurons, as key regulators of excitability, may mediate much of this imbalance, yet we know little about the way in which inhibitory deficits perturb excitability. In this review, we explore inhibitory control of excitability and the potential contribution of altered inhibition to amyotrophic lateral sclerosis disease processes and vulnerabilities, identifying important windows of therapeutic opportunity and potential interventions, specifically targeting inhibitory control at key disease stages.
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Affiliation(s)
- Rosemary Clark
- Menzies Institute for Medical Research, University of Tasmania, Hobart TAS 7000, Australia
| | - Catherine Blizzard
- Menzies Institute for Medical Research, University of Tasmania, Hobart TAS 7000, Australia
| | - Tracey Dickson
- Menzies Institute for Medical Research, University of Tasmania, Hobart TAS 7000, Australia
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38
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Donovan MD, Boylan GB, Murray DM, Cryan JF, Griffin BT. Treating disorders of the neonatal central nervous system: pharmacokinetic and pharmacodynamic considerations with a focus on antiepileptics. Br J Clin Pharmacol 2015; 81:62-77. [PMID: 26302437 DOI: 10.1111/bcp.12753] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 08/05/2015] [Accepted: 08/13/2015] [Indexed: 12/31/2022] Open
Abstract
A major consideration in the treatment of neonatal disorders is that the selected drug, dose and dosage frequency is safe, effective and appropriate for the intended patient population. Thus, a thorough knowledge of the pharmacokinetics and pharmacodynamics of the chosen drug within the patient population is essential. In paediatric and neonatal populations two additional challenges can often complicate drug treatment - the inherently greater physiological variability, and a lack of robust clinical evidence of therapeutic range. There has traditionally been an overreliance in paediatric medicine on extrapolating doses from adult values by adjusting for bodyweight or body surface area, but many other sources of variability exist which complicate the choice of dose in neonates. The lack of reliable drug dosage data in neonates has been highlighted by regulatory authorities, as only ~50% of the most commonly used paediatric medicines have been examined in a paediatric population. Moreover, there is a paucity of information on the pharmacokinetic parameters which affect drug concentrations in different body tissues, and pharmacodynamic responses to drugs in the neonate. Thus, in the present review, we draw attention to the main pharmacokinetic factors that influence the unbound brain concentration of neuroactive drugs. Moreover, the pharmacodynamic differences between neonates and adults that affect the activity of centrally-acting therapeutic agents are briefly examined, with a particular emphasis on antiepileptic drugs.
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Affiliation(s)
- Maria D Donovan
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland.,Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Geraldine B Boylan
- Department of Paediatrics and Child Health, University College Cork, Cork, Ireland.,Irish Centre for Fetal and Neonatal Translational Research, University College Cork and Cork University Maternity Hospital, Cork, Ireland
| | - Deirdre M Murray
- Department of Paediatrics and Child Health, University College Cork, Cork, Ireland
| | - John F Cryan
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland.,Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Brendan T Griffin
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland
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39
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Kang SK, Johnston MV, Kadam SD. Acute TrkB inhibition rescues phenobarbital-resistant seizures in a mouse model of neonatal ischemia. Eur J Neurosci 2015; 42:2792-804. [PMID: 26452067 PMCID: PMC4715496 DOI: 10.1111/ejn.13094] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 09/17/2015] [Accepted: 09/29/2015] [Indexed: 02/04/2023]
Abstract
Neonatal seizures are commonly associated with hypoxic-ischemic encephalopathy. Phenobarbital (PB) resistance is common and poses a serious challenge in clinical management. Using a newly characterized neonatal mouse model of ischemic seizures, this study investigated a novel strategy for rescuing PB resistance. A small-molecule TrkB antagonist, ANA12, used to selectively and transiently block post-ischemic BDNF-TrkB signaling in vivo, determined whether rescuing TrkB-mediated post-ischemic degradation of the K(+)-Cl(-) co-transporter (KCC2) rescued PB-resistant seizures. The anti-seizure efficacy of ANA12 + PB was quantified by (i) electrographic seizure burden using acute continuous video-electroencephalograms and (ii) post-treatment expression levels of KCC2 and NKCC1 using Western blot analysis in postnatal day (P)7 and P10 CD1 pups with unilateral carotid ligation. ANA12 significantly rescued PB-resistant seizures at P7 and improved PB efficacy at P10. A single dose of ANA12 + PB prevented the post-ischemic degradation of KCC2 for up to 24 h. As anticipated, ANA12 by itself had no anti-seizure properties and was unable to prevent KCC2 degradation at 24 h without follow-on PB. This indicates that unsubdued seizures can independently lead to KCC2 degradation via non-TrkB-dependent pathways. This study, for the first time as a proof-of-concept, reports the potential therapeutic value of KCC2 modulation for the management of PB-resistant seizures in neonates. Future investigations are required to establish the mechanistic link between ANA12 and the prevention of KCC2 degradation.
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Affiliation(s)
- S K Kang
- Neuroscience Laboratory, Hugo Moser Research Institute at Kennedy Krieger, 716 North Broadway, Baltimore, MD, 21205, USA
| | - M V Johnston
- Neuroscience Laboratory, Hugo Moser Research Institute at Kennedy Krieger, 716 North Broadway, Baltimore, MD, 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - S D Kadam
- Neuroscience Laboratory, Hugo Moser Research Institute at Kennedy Krieger, 716 North Broadway, Baltimore, MD, 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
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40
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Lykke K, Töllner K, Römermann K, Feit PW, Erker T, MacAulay N, Löscher W. Structure-activity relationships of bumetanide derivatives: correlation between diuretic activity in dogs and inhibition of the human NKCC2A transporter. Br J Pharmacol 2015; 172:4469-4480. [PMID: 26101812 PMCID: PMC4562508 DOI: 10.1111/bph.13231] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 05/28/2015] [Accepted: 06/12/2015] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE The N-K-Cl cotransporters (NKCCs) mediate the coupled, electroneutral movement of Na+ , K+ and Cl- ions across cell membranes. There are two isoforms of this cation co-transporter, NKCC1 and NKCC2. NKCC2 is expressed primarily in the kidney and is the target of diuretics such as bumetanide. Bumetanide was discovered by screening ∼5000 3-amino-5-sulfamoylbenzoic acid derivatives, long before NKCC2 was identified in the kidney. Therefore, structure-activity studies on effects of bumetanide derivatives on NKCC2 are not available. EXPERIMENTAL APPROACH In this study, the effect of a series of diuretically active bumetanide derivatives was investigated on human NKCC2 variant A (hNKCC2A) expressed in Xenopus laevis oocytes. KEY RESULTS Bumetanide blocked hNKCC2A transport with an IC50 of 4 μM. There was good correlation between the diuretic potency of bumetanide and its derivatives in dogs and their inhibition of hNKCC2A (r2 = 0.817; P < 0.01). Replacement of the carboxylic group of bumetanide by a non-ionic residue, for example, an anilinomethyl group, decreased inhibition of hNKCC2A, indicating that an acidic group was required for transporter inhibition. Exchange of the phenoxy group of bumetanide for a 4-chloroanilino group or the sulfamoyl group by a methylsulfonyl group resulted in compounds with higher potency to inhibit hNKCC2A than bumetanide. CONCLUSIONS AND IMPLICATIONS The X. laevis oocyte expression system used in these experiments allowed analysis of the structural requirements that determine relative potency of loop diuretics on human NKCC2 splice variants, and may lead to the discovery of novel high-ceiling diuretics.
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Affiliation(s)
- Kasper Lykke
- Department of Cellular and Molecular Medicine, University of CopenhagenCopenhagen, Denmark
| | - Kathrin Töllner
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
- Center for Systems NeuroscienceHannover, Germany
| | - Kerstin Römermann
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
- Center for Systems NeuroscienceHannover, Germany
| | - Peter W Feit
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
| | - Thomas Erker
- Department of Medicinal Chemistry, University of ViennaVienna, Austria
| | - Nanna MacAulay
- Department of Cellular and Molecular Medicine, University of CopenhagenCopenhagen, Denmark
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
- Center for Systems NeuroscienceHannover, Germany
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Hamidi S, Avoli M. KCC2 function modulates in vitro ictogenesis. Neurobiol Dis 2015; 79:51-8. [PMID: 25926348 PMCID: PMC4880462 DOI: 10.1016/j.nbd.2015.04.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 04/20/2015] [Accepted: 04/21/2015] [Indexed: 12/29/2022] Open
Abstract
GABAA receptor-mediated inhibition is active and may contribute to epileptiform synchronization. The efficacy of inhibition relies on low levels of intracellular Cl(-), which are controlled by KCC2 activity. This evidence has led us to analyze with field potential recordings the effects induced by the KCC2 blockers VU0240551 (10 μM) or bumetanide (50 μM) and by the KCC2 enhancer CLP257 (100 μM) on the epileptiform discharges generated by piriform and entorhinal cortices (PC and EC, respectively) in an in vitro brain slice preparation. Ictal- and interictal-like discharges along with high-frequency oscillations (HFOs, ripples: 80-200 Hz, fast ripples: 250-500 Hz) were recorded from these two regions during application of 4-aminopyridine (4AP, 50 μM). Blocking KCC2 activity with either VU024055 or high doses of bumetanide abolished ictal discharge in both PC and EC; in addition, these experimental procedures decreased the interval of occurrence and duration of interictal discharges. In contrast, enhancing KCC2 activity with CLP257 increased ictal discharge duration in both regions. Finally, blocking KCC2 activity decreased the duration and amplitude of pharmacologically isolated synchronous GABAergic events whereas enhancing KCC2 activity led to an increase in their duration. Our data demonstrate that in vitro ictogenesis is abolished or facilitated by inhibiting or enhancing KCC2 activity, respectively. We propose that these effects may result from the reduction of GABAA receptor-dependent increases in extracellular K(+) that are known to rest on KCC2 function.
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Affiliation(s)
- Shabnam Hamidi
- Montreal Neurological Institute and Department of Neurology & Neurosurgery, McGill University, 3801 University Street, Montréal, QC, Canada H3A 2B4 McGill University, 3801 University Street, Montréal, QC, Canada, H3A 2B4
| | - Massimo Avoli
- Montreal Neurological Institute and Department of Neurology & Neurosurgery, McGill University, 3801 University Street, Montréal, QC, Canada H3A 2B4 McGill University, 3801 University Street, Montréal, QC, Canada, H3A 2B4.
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Shetty J. Neonatal seizures in hypoxic-ischaemic encephalopathy--risks and benefits of anticonvulsant therapy. Dev Med Child Neurol 2015; 57 Suppl 3:40-3. [PMID: 25800491 DOI: 10.1111/dmcn.12724] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/17/2014] [Indexed: 12/14/2022]
Abstract
The risk of seizures is at its highest during the neonatal period, and the most common cause of neonatal seizures is hypoxic-ischaemic encephalopathy (HIE). This enhanced vulnerability is caused by an imbalance in the expression of receptors for excitatory and inhibitory neurotransmission, which is age dependent. There has been progress in detecting the electrophysiological abnormalities associated with seizures using amplitude-integrated electroencephalography (aEEG). Data from animal studies indicate a variety of risk factors for seizures, but there are limited clinical data looking at the long-term neurodevelopmental consequences of seizures alone. Neonatal seizures are also associated with increased risk of further epileptic seizures; however, it is less clear whether or not this results from an underlying pathology, and whether or not seizures confer additional risk. Phenobarbital and phenytoin are still the first-line antiepileptic drugs (AEDs) used to treat neonatal seizures, although they are effective in only one-third of affected infants. Furthermore, based on findings from animal studies, there are concerns regarding the risks associated with using these AEDs. Clinicians face a difficult challenge because, although seizures can be easily identified using aEEG, treatment options are limited, and there are uncertainties regarding treatment outcomes. There is a need to obtain long-term follow-up data, comparing groups of infants treated with or without current therapies. If these analyses indicate a definite benefit of treating neonatal seizures, then novel therapeutic approaches should be developed.
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Affiliation(s)
- Jayakara Shetty
- Department of Paediatric Neurosciences, Royal Hospital for Sick Children, Edinburgh, UK
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Silbert BI, Heaton AE, Cash RFH, James I, Dunne JW, Lawn ND, Silbert PL, Mastaglia FL, Thickbroom GW. Evidence for an excitatory GABAA response in human motor cortex in idiopathic generalised epilepsy. Seizure 2015; 26:36-42. [PMID: 25799900 DOI: 10.1016/j.seizure.2015.01.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 12/28/2014] [Accepted: 01/23/2015] [Indexed: 12/24/2022] Open
Abstract
PURPOSE Impaired GABAergic inhibition has been implicated in the pathophysiology of epilepsy. The possibility of a paradoxical excitatory effect of GABA in epilepsy has been suggested, but has not been investigated in vivo. We investigated pre- and post-synaptic GABAergic mechanisms in patients with idiopathic generalised epilepsy (IGE). METHOD In 10 patients and 12 control subjects we explored short- and long-interval intracortical inhibition (SICI, LICI; post-synaptic GABAA and GABAB-mediated respectively) and long-interval intracortical facilitation (LICF; pre-synaptic disinhibition) using transcranial magnetic stimulation. RESULTS While post-synaptic GABAB-mediated inhibition was unchanged in IGE (p=0.09), LICF was reduced compared to controls (controls: 141±17% of baseline; untreated patients: 107±12%, p=0.2; treated patients: 79±10%, p=0.003). GABAA-mediated inhibition was reduced in untreated patients (response amplitude 56±4% of baseline vs. 26±6% in controls, p=0.004) and normalised with treatment (37±12%, p=0.5 vs. controls). When measured during LICI, GABAA-mediated inhibition became excitatory in untreated IGE (response amplitude 120±10% of baseline, p=0.017), but not in treated patients. CONCLUSION Pre- and post-synaptic GABA-mediated inhibitory mechanisms are altered in IGE. The findings lend in vivo support to evidence from experimental models and in vitro studies of human epileptic brain tissue that GABA may have a paradoxical excitatory role in ictogenesis.
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Affiliation(s)
- Benjamin I Silbert
- Western Australian Neuroscience Research Institute, University of Western Australia, 4th Floor, A Block, QEII Medical Centre, Verdun Street, Nedlands, Perth, Western Australia 6009, Australia
| | - Alexandra E Heaton
- Western Australian Neuroscience Research Institute, University of Western Australia, 4th Floor, A Block, QEII Medical Centre, Verdun Street, Nedlands, Perth, Western Australia 6009, Australia
| | - Robin F H Cash
- Western Australian Neuroscience Research Institute, University of Western Australia, 4th Floor, A Block, QEII Medical Centre, Verdun Street, Nedlands, Perth, Western Australia 6009, Australia; Division of Brain, Imaging and Behaviour - Systems Neuroscience, Toronto Western Research Institute, University Health Network, 339 Bathurst Street, MP14-324, Toronto, Ontario M5T 2S8, Canada
| | - Ian James
- Centre for Clinical Immunology and Biomedical Statistics, Institute for Immunology and Infectious Diseases, Murdoch University, Building 390, Discovery Way, Murdoch, Perth, Western Australia 6150, Australia
| | - John W Dunne
- Department of Neurology, Royal Perth Hospital, Level 8, A Block, GPO Box X2213, Perth, Western Australia 6001, Australia
| | - Nicholas D Lawn
- Department of Neurology, Royal Perth Hospital, Level 8, A Block, GPO Box X2213, Perth, Western Australia 6001, Australia
| | - Peter L Silbert
- Department of Neurology, Royal Perth Hospital, Level 8, A Block, GPO Box X2213, Perth, Western Australia 6001, Australia
| | - Frank L Mastaglia
- Western Australian Neuroscience Research Institute, University of Western Australia, 4th Floor, A Block, QEII Medical Centre, Verdun Street, Nedlands, Perth, Western Australia 6009, Australia
| | - Gary W Thickbroom
- Western Australian Neuroscience Research Institute, University of Western Australia, 4th Floor, A Block, QEII Medical Centre, Verdun Street, Nedlands, Perth, Western Australia 6009, Australia.
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44
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Khazipov R, Valeeva G, Khalilov I. Depolarizing GABA and developmental epilepsies. CNS Neurosci Ther 2014; 21:83-91. [PMID: 25438879 DOI: 10.1111/cns.12353] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Revised: 10/14/2014] [Accepted: 10/20/2014] [Indexed: 12/22/2022] Open
Abstract
Early in development, GABA, which is the main inhibitory neurotransmitter in adult brain, depolarizes immature neurons and exerts dual--excitatory and shunting/inhibitory--effects in the developing neuronal networks. The present review discusses some general questions, including the properties of excitation at depolarizing GABAergic synapse and shunting inhibition by depolarizing GABA; technical issues in exploration of depolarizing GABA using various techniques and preparations, including the developmental aspects of traumatic injury and what is known (or rather unknown) on the actions of GABA in vivo; complex roles of depolarizing GABA in developmental epilepsies, including a contribution of depolarizing GABA to enhanced excitability in the immature networks, caused by repetitive seizures accumulation of intracellular chloride concentration that increases excitatory GABA power and its synchronizing proconvulsive effects, and correction of chloride homeostasis as a potential strategy to treat neonatal seizures.
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Affiliation(s)
- Roustem Khazipov
- INMED-INSERM U901, Marseille, France; Aix-Marseille University, Marseille, France; Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
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45
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Ko MC, Lee MC, Amstislavskaya TG, Tikhonova MA, Yang YL, Lu KT. Inhibition of NKCC1 attenuated hippocampal LTP formation and inhibitory avoidance in rat. PLoS One 2014; 9:e106692. [PMID: 25369049 PMCID: PMC4219661 DOI: 10.1371/journal.pone.0106692] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 08/08/2014] [Indexed: 11/18/2022] Open
Abstract
The loop diuretic bumetanide (Bumex) is thought to have antiepileptic properties via modulate GABAA mediated signaling through their antagonism of cation-chloride cotransporters. Given that loop diuretics may act as antiepileptic drugs that modulate GABAergic signaling, we sought to investigate whether they also affect hippocampal function. The current study was performed to evaluate the possible role of NKCC1 on the hippocampal function. Brain slice extracellular recording, inhibitory avoidance, and western blot were applied in this study. Results showed that hippocampal Long-term potentiation was attenuated by suprafusion of NKCC1 inhibitor bumetanide, in a dose dependent manner. Sequent experiment result showed that Intravenous injection of bumetanide (15.2 mg/kg) 30 min prior to the training session blocked inhibitory avoidance learning significantly. Subsequent control experiment's results excluded the possible non-specific effect of bumetanide on avoidance learning. We also found the phosphorylation of hippocampal MAPK was attenuated after bumetanide administration. These results suggested that hippocampal NKCC1 may via MAPK signaling cascade to possess its function.
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Affiliation(s)
- Meng Chang Ko
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Min Chong Lee
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Tamara G. Amstislavskaya
- Laboratory of Biological Psychiatry, State Research Institute of Physiology and Fundamental Medicine SB RAMS, Novosibirsk, Russia
| | - Maria A. Tikhonova
- Laboratory of Biological Psychiatry, State Research Institute of Physiology and Fundamental Medicine SB RAMS, Novosibirsk, Russia
| | - Yi-Ling Yang
- Department of Biochemical Science and Technology, National Chia-Yi University, Chia-Yi, Taiwan
| | - Kwok-Tung Lu
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
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46
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Alessi DR, Zhang J, Khanna A, Hochdörfer T, Shang Y, Kahle KT. The WNK-SPAK/OSR1 pathway: master regulator of cation-chloride cotransporters. Sci Signal 2014; 7:re3. [PMID: 25028718 DOI: 10.1126/scisignal.2005365] [Citation(s) in RCA: 189] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The WNK-SPAK/OSR1 kinase complex is composed of the kinases WNK (with no lysine) and SPAK (SPS1-related proline/alanine-rich kinase) or the SPAK homolog OSR1 (oxidative stress-responsive kinase 1). The WNK family senses changes in intracellular Cl(-) concentration, extracellular osmolarity, and cell volume and transduces this information to sodium (Na(+)), potassium (K(+)), and chloride (Cl(-)) cotransporters [collectively referred to as CCCs (cation-chloride cotransporters)] and ion channels to maintain cellular and organismal homeostasis and affect cellular morphology and behavior. Several genes encoding proteins in this pathway are mutated in human disease, and the cotransporters are targets of commonly used drugs. WNKs stimulate the kinases SPAK and OSR1, which directly phosphorylate and stimulate Cl(-)-importing, Na(+)-driven CCCs or inhibit the Cl(-)-extruding, K(+)-driven CCCs. These coordinated and reciprocal actions on the CCCs are triggered by an interaction between RFXV/I motifs within the WNKs and CCCs and a conserved carboxyl-terminal docking domain in SPAK and OSR1. This interaction site represents a potentially druggable node that could be more effective than targeting the cotransporters directly. In the kidney, WNK-SPAK/OSR1 inhibition decreases epithelial NaCl reabsorption and K(+) secretion to lower blood pressure while maintaining serum K(+). In neurons, WNK-SPAK/OSR1 inhibition could facilitate Cl(-) extrusion and promote γ-aminobutyric acidergic (GABAergic) inhibition. Such drugs could have efficacy as K(+)-sparing blood pressure-lowering agents in essential hypertension, nonaddictive analgesics in neuropathic pain, and promoters of GABAergic inhibition in diseases associated with neuronal hyperactivity, such as epilepsy, spasticity, neuropathic pain, schizophrenia, and autism.
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Affiliation(s)
- Dario R Alessi
- MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland
| | - Jinwei Zhang
- MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland
| | - Arjun Khanna
- Department of Neurosurgery, Massachusetts General Hospital, and Harvard Medical School, Boston, MA 02115, USA
| | - Thomas Hochdörfer
- MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland
| | - Yuze Shang
- Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA 02115, USA
| | - Kristopher T Kahle
- Department of Neurosurgery, Massachusetts General Hospital, and Harvard Medical School, Boston, MA 02115, USA. Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA 02115, USA.
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Deidda G, Bozarth IF, Cancedda L. Modulation of GABAergic transmission in development and neurodevelopmental disorders: investigating physiology and pathology to gain therapeutic perspectives. Front Cell Neurosci 2014; 8:119. [PMID: 24904277 PMCID: PMC4033255 DOI: 10.3389/fncel.2014.00119] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 04/14/2014] [Indexed: 01/30/2023] Open
Abstract
During mammalian ontogenesis, the neurotransmitter GABA is a fundamental regulator of neuronal networks. In neuronal development, GABAergic signaling regulates neural proliferation, migration, differentiation, and neuronal-network wiring. In the adult, GABA orchestrates the activity of different neuronal cell-types largely interconnected, by powerfully modulating synaptic activity. GABA exerts these functions by binding to chloride-permeable ionotropic GABAA receptors and metabotropic GABAB receptors. According to its functional importance during development, GABA is implicated in a number of neurodevelopmental disorders such as autism, Fragile X, Rett syndrome, Down syndrome, schizophrenia, Tourette's syndrome and neurofibromatosis. The strength and polarity of GABAergic transmission is continuously modulated during physiological, but also pathological conditions. For GABAergic transmission through GABAA receptors, strength regulation is achieved by different mechanisms such as modulation of GABAA receptors themselves, variation of intracellular chloride concentration, and alteration in GABA metabolism. In the never-ending effort to find possible treatments for GABA-related neurological diseases, of great importance would be modulating GABAergic transmission in a safe and possibly physiological way, without the dangers of either silencing network activity or causing epileptic seizures. In this review, we will discuss the different ways to modulate GABAergic transmission normally at work both during physiological and pathological conditions. Our aim is to highlight new research perspectives for therapeutic treatments that reinstate natural and physiological brain functions in neuro-pathological conditions.
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Affiliation(s)
- Gabriele Deidda
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia Genova, Italy
| | - Ignacio F Bozarth
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia Genova, Italy
| | - Laura Cancedda
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia Genova, Italy
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48
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White HS, Löscher W. Searching for the ideal antiepileptogenic agent in experimental models: single treatment versus combinatorial treatment strategies. Neurotherapeutics 2014; 11:373-84. [PMID: 24425186 PMCID: PMC3996126 DOI: 10.1007/s13311-013-0250-1] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
A major unmet medical need is the lack of treatments to prevent (or modify) epilepsy in patients at risk, for example, after epileptogenic brain insults such as traumatic brain injury, stroke, or prolonged acute symptomatic seizures like complex febrile seizures or status epilepticus. Typically, following such brain insults there is a seizure-free interval ("latent period"), lasting months to years before the onset of spontaneous recurrent epileptic seizures. The latent period after a brain insult offers a window of opportunity in which an appropriate treatment may prevent or modify the epileptogenic process induced by a brain insult. A similar latent period occurs in patients with epileptogenic gene mutations. Studies using animal models of epilepsy have led to a greater understanding of the factors underlying epileptogenesis and have provided significant insight into potential targets by which the development of epilepsy may be prevented or modified. This review focuses largely on some of the most common animal models of epileptogenesis and their potential utility for evaluating proposed antiepileptogenic therapies and identifying useful biomarkers. The authors also describe some of the limitations of using animal models in the search for therapies that move beyond the symptomatic treatment of epilepsy. Promising results of previous studies designed to evaluate antiepileptogenesis and the role of monotherapy versus polytherapy approaches are also discussed. Recent data from both models of genetic and acquired epilepsies strongly indicate that it is possible to prevent or modify epileptogenesis, and, hopefully, such promising results can ultimately be translated into the clinic.
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Affiliation(s)
- H. Steve White
- />Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT USA
| | - Wolfgang Löscher
- />Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany
- />Center for Systems Neuroscience, Hannover, Germany
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49
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Scharfman HE, Brooks-Kayal AR. Is plasticity of GABAergic mechanisms relevant to epileptogenesis? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 813:133-50. [PMID: 25012373 DOI: 10.1007/978-94-017-8914-1_11] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Numerous changes in GABAergic neurons, receptors, and inhibitory mechanisms have been described in temporal lobe epilepsy (TLE), either in humans or in animal models. Nevertheless, there remains a common assumption that epilepsy can be explained by simply an insufficiency of GABAergic inhibition. Alternatively, investigators have suggested that there is hyperinhibition that masks an underlying hyperexcitability. Here we examine the status epilepticus (SE) models of TLE and focus on the dentate gyrus of the hippocampus, where a great deal of data have been collected. The types of GABAergic neurons and GABAA receptors are summarized under normal conditions and after SE. The role of GABA in development and in adult neurogenesis is discussed. We suggest that instead of "too little or too much" GABA there is a complexity of changes after SE that makes the emergence of chronic seizures (epileptogenesis) difficult to understand mechanistically, and difficult to treat. We also suggest that this complexity arises, at least in part, because of the remarkable plasticity of GABAergic neurons and GABAA receptors in response to insult or injury.
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Affiliation(s)
- Helen E Scharfman
- The Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, USA,
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50
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Baraban SC, Löscher W. What new modeling approaches will help us identify promising drug treatments? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 813:283-94. [PMID: 25012385 DOI: 10.1007/978-94-017-8914-1_23] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Despite the development of numerous novel antiepileptic drugs (AEDs) in recent years, several unmet clinical needs remain, including resistance to AEDs in about 30 % of patients with epilepsy, adverse effects of AEDs that can reduce quality of life, and the lack of treatments that can prevent development of epilepsy in patients at risk. Animal models of seizures and epilepsy have been instrumental in the discovery and preclinical development of novel AEDs, but obviously the previously used models have failed to identify drugs that address unmet medical needs. Thus, we urgently need fresh ideas for improving preclinical AED development. In this review, a number of promising models will be described, including the use of simple vertebrates such as zebrafish (Danio rerio), large animal models such as the dog and newly characterized rodent models of pharmacoresistant epilepsy. While these strategies, like any animal model approach also have their limitations, they offer hope that new more effective AEDs will be identified in the coming years.
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Affiliation(s)
- Scott C Baraban
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California, San Francisco, CA, 94143, USA,
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