1
|
Yuliati A, Zayek M, Maertens P. The Impact of Phenobarbital on the Ability of Electroencephalogram to Predict Adverse Outcome in Asphyxiated Neonates during Therapeutic Hypothermia. Am J Perinatol 2024; 41:e1681-e1688. [PMID: 37186086 DOI: 10.1055/s-0043-1768487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
OBJECTIVE Classification of electroencephalogram (EEG) background has been established to predict outcome in neonates with hypoxic ischemic encephalopathy (HIE). However, the impact of phenobarbital therapy on the predictability of EEG background has not been studied. Our objective is to determine if EEG background after treatment with phenobarbital during therapeutic hypothermia (TH) remains a good predictor for brain injury in neonates with HIE. STUDY DESIGN This is a single-center, retrospective study of consecutive neonates with HIE who underwent TH and EEG monitoring from October 2017 to March 2021. Per institutional protocol, all infants received a dose of prophylactic phenobarbital and bumetanide therapy at the onset of TH for sedative and neuroprotective measures. The initial 3 hours of EEG background activity was classified based on national guidelines. Infants were separated into two groups based on EEG background scores: group 1 (normal-mild, n = 30) and group 2 (moderate-severe, n = 36). Brain magnetic resonance imaging (MRI) results were scored based on the National Institute of Child Health and Human Development (NICHD) criteria. Adverse outcomes were defined as death before MRI or NICHD brain injury score > 1A. RESULTS Infants in group 2 had lower Apgar scores at 5 minutes of age, severe acidemia, moderate to severe encephalopathy score, and earlier initiation of EEG monitoring than infants in group 1. Moderate to severe EEG background score was associated with presence of brain injury on MRI or death (p = 0.003), and this association remained significant even after adjustment for independent risk factors (odds ratio = 56.24 [95% confidence interval = 1.841-1718], p = 0.021). CONCLUSION Phenobarbital therapy does not affect the ability of EEG to predict adverse outcome in infants with perinatal asphyxia during TH. KEY POINTS · EEG has a clinical utility for predicting outcome in neonates with hypoxia-ischemia.. · Phenobarbital therapy is commonly used in neonates, and may impact EEG background findings.. · In spite phenobarbital therapy, moderate to severe EEG background abnormalities in infants with perinatal asphyxia during TH remain an excellent predictor for poor outcome..
Collapse
Affiliation(s)
- Asri Yuliati
- Division of Pediatric Neurology, Department of Pediatrics, University of South Alabama, Mobile, Alabama
| | - Michael Zayek
- Department of Pediatrics, Division of Neonatology, University of South Alabama, Mobile, Alabama
| | - Paul Maertens
- Division of Pediatric Neurology, Department of Pediatrics, University of South Alabama, Mobile, Alabama
| |
Collapse
|
2
|
Abiramalatha T, Thanigainathan S, Ramaswamy VV, Pressler R, Brigo F, Hartmann H. Anti-seizure medications for neonates with seizures. Cochrane Database Syst Rev 2023; 10:CD014967. [PMID: 37873971 PMCID: PMC10594593 DOI: 10.1002/14651858.cd014967.pub2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
BACKGROUND Newborn infants are more prone to seizures than older children and adults. The neuronal injury caused by seizures in neonates often results in long-term neurodevelopmental sequelae. There are several options for anti-seizure medications (ASMs) in neonates. However, the ideal choice of first-, second- and third-line ASM is still unclear. Further, many other aspects of seizure management such as whether ASMs should be initiated for only-electrographic seizures and how long to continue the ASM once seizure control is achieved are elusive. OBJECTIVES 1. To assess whether any ASM is more or less effective than an alternative ASM (both ASMs used as first-, second- or third-line treatment) in achieving seizure control and improving neurodevelopmental outcomes in neonates with seizures. We analysed EEG-confirmed seizures and clinically-diagnosed seizures separately. 2. To assess maintenance therapy with ASM versus no maintenance therapy after achieving seizure control. We analysed EEG-confirmed seizures and clinically-diagnosed seizures separately. 3. To assess treatment of both clinical and electrographic seizures versus treatment of clinical seizures alone in neonates. SEARCH METHODS We searched MEDLINE, Embase, CENTRAL, Epistemonikos and three databases in May 2022 and June 2023. These searches were not limited other than by study design to trials. SELECTION CRITERIA We included randomised controlled trials (RCTs) that included neonates with EEG-confirmed or clinically diagnosed seizures and compared (1) any ASM versus an alternative ASM, (2) maintenance therapy with ASM versus no maintenance therapy, and (3) treatment of clinical or EEG seizures versus treatment of clinical seizures alone. DATA COLLECTION AND ANALYSIS Two review authors assessed trial eligibility, risk of bias and independently extracted data. We analysed treatment effects in individual trials and reported risk ratio (RR) for dichotomous data, and mean difference (MD) for continuous data, with respective 95% confidence interval (CI). We used GRADE to assess the certainty of evidence. MAIN RESULTS We included 18 trials (1342 infants) in this review. Phenobarbital versus levetiracetam as first-line ASM in EEG-confirmed neonatal seizures (one trial) Phenobarbital is probably more effective than levetiracetam in achieving seizure control after first loading dose (RR 2.32, 95% CI 1.63 to 3.30; 106 participants; moderate-certainty evidence), and after maximal loading dose (RR 2.83, 95% CI 1.78 to 4.50; 106 participants; moderate-certainty evidence). However, we are uncertain about the effect of phenobarbital when compared to levetiracetam on mortality before discharge (RR 0.30, 95% CI 0.04 to 2.52; 106 participants; very low-certainty evidence), requirement of mechanical ventilation (RR 1.21, 95% CI 0.76 to 1.91; 106 participants; very low-certainty evidence), sedation/drowsiness (RR 1.74, 95% CI 0.68 to 4.44; 106 participants; very low-certainty evidence) and epilepsy post-discharge (RR 0.92, 95% CI 0.48 to 1.76; 106 participants; very low-certainty evidence). The trial did not report on mortality or neurodevelopmental disability at 18 to 24 months. Phenobarbital versus phenytoin as first-line ASM in EEG-confirmed neonatal seizures (one trial) We are uncertain about the effect of phenobarbital versus phenytoin on achieving seizure control after maximal loading dose of ASM (RR 0.97, 95% CI 0.54 to 1.72; 59 participants; very low-certainty evidence). The trial did not report on mortality or neurodevelopmental disability at 18 to 24 months. Maintenance therapy with ASM versus no maintenance therapy in clinically diagnosed neonatal seizures (two trials) We are uncertain about the effect of short-term maintenance therapy with ASM versus no maintenance therapy during the hospital stay (but discontinued before discharge) on the risk of repeat seizures before hospital discharge (RR 0.76, 95% CI 0.56 to 1.01; 373 participants; very low-certainty evidence). Maintenance therapy with ASM compared to no maintenance therapy may have little or no effect on mortality before discharge (RR 0.69, 95% CI 0.39 to 1.22; 373 participants; low-certainty evidence), mortality at 18 to 24 months (RR 0.94, 95% CI 0.34 to 2.61; 111 participants; low-certainty evidence), neurodevelopmental disability at 18 to 24 months (RR 0.89, 95% CI 0.13 to 6.12; 108 participants; low-certainty evidence) and epilepsy post-discharge (RR 3.18, 95% CI 0.69 to 14.72; 126 participants; low-certainty evidence). Treatment of both clinical and electrographic seizures versus treatment of clinical seizures alone in neonates (two trials) Treatment of both clinical and electrographic seizures when compared to treating clinical seizures alone may have little or no effect on seizure burden during hospitalisation (MD -1871.16, 95% CI -4525.05 to 782.73; 68 participants; low-certainty evidence), mortality before discharge (RR 0.59, 95% CI 0.28 to 1.27; 68 participants; low-certainty evidence) and epilepsy post-discharge (RR 0.75, 95% CI 0.12 to 4.73; 35 participants; low-certainty evidence). The trials did not report on mortality or neurodevelopmental disability at 18 to 24 months. We report data from the most important comparisons here; readers are directed to Results and Summary of Findings tables for all comparisons. AUTHORS' CONCLUSIONS Phenobarbital as a first-line ASM is probably more effective than levetiracetam in achieving seizure control after the first loading dose and after the maximal loading dose of ASM (moderate-certainty evidence). Phenobarbital + bumetanide may have little or no difference in achieving seizure control when compared to phenobarbital alone (low-certainty evidence). Limited data and very low-certainty evidence preclude us from drawing any reasonable conclusion on the effect of using one ASM versus another on other short- and long-term outcomes. In neonates who achieve seizure control after the first loading dose of phenobarbital, maintenance therapy compared to no maintenance ASM may have little or no effect on all-cause mortality before discharge, mortality by 18 to 24 months, neurodevelopmental disability by 18 to 24 months and epilepsy post-discharge (low-certainty evidence). In neonates with hypoxic-ischaemic encephalopathy, treatment of both clinical and electrographic seizures when compared to treating clinical seizures alone may have little or no effect on seizure burden during hospitalisation, all-cause mortality before discharge and epilepsy post-discharge (low-certainty evidence). All findings of this review apply only to term and late preterm neonates. We need well-designed RCTs for each of the three objectives of this review to improve the precision of the results. These RCTs should use EEG to diagnose seizures and should be adequately powered to assess long-term neurodevelopmental outcomes. We need separate RCTs evaluating the choice of ASM in preterm infants.
Collapse
Affiliation(s)
- Thangaraj Abiramalatha
- Neonatology, KMCH Institute of Health Sciences and Research (KMCHIHSR), Coimbatore, Tamil Nadu, India
- KMCH Research Foundation, Coimbatore, Tamil Nadu, India
| | | | | | - Ronit Pressler
- Clinical Neurophysiology, Great Ormond Street Hospital for Children, London, UK
- Clinical Neurophysiology and Neonatology, Cambridge University Hospital, Cambridge, UK
- Clinical Neuroscience, UCL- Great Ormond Street Institute of Child Health, London, UK
| | - Francesco Brigo
- Neurology, Hospital of Merano (SABES-ASDAA), Teaching Hospital of Paracelsus Medical University, Merano-Meran, Italy
- Innovation Research and Teaching Service (SABES-ASDAA), Teaching Hospital of the Paracelsus Medical Private University (PMU), Bolzano-Bozen, Italy
| | - Hans Hartmann
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| |
Collapse
|
3
|
Langton RL, Sharma S, Tiarks GC, Bassuk AG, Glykys J. Lacosamide decreases neonatal seizures without increasing apoptosis. Epilepsia 2022; 63:3051-3065. [PMID: 36168798 PMCID: PMC9742288 DOI: 10.1111/epi.17423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 09/26/2022] [Accepted: 09/26/2022] [Indexed: 01/11/2023]
Abstract
OBJECTIVE Many seizing neonates fail to respond to first-line anticonvulsant medications. Phenobarbital, an allosteric modulator of γ-aminobutyric acid type A (GABAA ) receptors, has low efficacy in treating neonatal seizures and causes neuronal apoptosis. Nonetheless, it is one of the most used anticonvulsants in this age group. In neonatal mice, phenobarbital's poor effectiveness is due in part to high intraneuronal chloride concentration, which causes GABA to exert depolarizing actions. Therefore, another approach to treat neonatal seizures could be to use anticonvulsants that do not rely on GABAergic modulation. We evaluated whether lacosamide decreases seizures in neonatal mice and whether it increases apoptosis in vitro and in vivo. METHODS In vitro, we measured the effect of different lacosamide concentrations on seizure-like activity induced by the pro-convulsant drug 4-aminopyridine in neocortical brain slices (layer IV/V) from neonatal (postnatal day 8-11) and adult (1-1.6 months old) C57BL/6J mice. In vivo, we recorded the effect of different lacosamide concentrations on neonatal behavioral seizures induced by kainic acid. We studied neocortical apoptosis in vitro and in vivo, measuring terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling signal and cleaved-caspase 3. RESULTS Lacosamide reduced epileptiform activity in neocortical brain slices of neonates and adults in a concentration-dependent manner. In vivo, lacosamide reduced the duration and number of behavioral seizures. Lacosamide did not increase total or neuronal apoptosis in the neocortex in vitro or in vivo. SIGNIFICANCE Lacosamide reduces neocortical seizure-like activity in neonatal mice in vitro and in vivo without an acute increase in apoptosis. Our results support the use of lacosamide to treat neonatal seizures, with the advantage of not increasing apoptosis acutely.
Collapse
Affiliation(s)
- Rachel L Langton
- Department of Pediatrics, Division of Child Neurology, University of Iowa, Iowa City, Iowa, USA.,Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa, USA
| | - Shaunik Sharma
- Department of Pediatrics, Division of Child Neurology, University of Iowa, Iowa City, Iowa, USA
| | - Grant C Tiarks
- Department of Pediatrics, Division of Child Neurology, University of Iowa, Iowa City, Iowa, USA
| | - Alexander G Bassuk
- Department of Pediatrics, Division of Child Neurology, University of Iowa, Iowa City, Iowa, USA.,Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa, USA.,Department of Neurology, University of Iowa, Iowa City, Iowa, USA
| | - Joseph Glykys
- Department of Pediatrics, Division of Child Neurology, University of Iowa, Iowa City, Iowa, USA.,Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa, USA.,Department of Neurology, University of Iowa, Iowa City, Iowa, USA
| |
Collapse
|
4
|
Kaila K, Löscher W. Bumetanide for neonatal seizures: no light in the pharmacokinetic/dynamic tunnel. Epilepsia 2022; 63:1868-1873. [PMID: 35524446 PMCID: PMC9545618 DOI: 10.1111/epi.17279] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 04/12/2022] [Indexed: 11/29/2022]
Abstract
In his editorial, Kevin Staley criticizes our recent work demonstrating the lack of effect of bumetanide in a novel model of neonatal seizures. The main points in our response are that (1) our work is on an asphyxia model, not one on "hypercarbia only"; (2) clinically relevant parenteral doses of bumetanide applied in vivo lead to concentrations in the brain parenchyma that are at least an order of magnitude lower than what would be sufficient to exert any direct effect—even a transient one—on neuronal functions, including neonatal seizures; and (3) moreover, bumetanide's molecular target in the brain is the Na‐K‐2Cl cotransporter NKCC1, which has vital functions in neurons, astrocytes, and oligodendrocytes as well as microglia. This would make it impossible even for highly brain‐permeant NKCC1 blockers to specifically target depolarizing and excitatory actions of γ‐aminobutyric acid in principal neurons of the brain, which is postulated as the rationale of clinical trials on neonatal seizures.
Collapse
Affiliation(s)
- Kai Kaila
- Molecular and Integrative Biosciences (MIBS) and Neuroscience Center (HiLIFE), University of Helsinki, Finland
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| |
Collapse
|
5
|
Staley KJ. Clarifications regarding bumetanide for neonatal seizures. Epilepsia 2022; 63:1863-1867. [PMID: 35524444 DOI: 10.1111/epi.17278] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 12/02/2021] [Indexed: 12/01/2022]
Affiliation(s)
- Kevin J Staley
- Neurology Department, Massachusetts General Hospital, Harvard Medical School
| |
Collapse
|
6
|
Abiramalatha T, Thanigainathan S, Ramaswamy VV, Pressler R, Brigo F, Hartmann H. Antiseizure medications for neonates with seizures. Hippokratia 2022. [DOI: 10.1002/14651858.cd014967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Thangaraj Abiramalatha
- Neonatology; Kovai Medical Center and Hospital (KMCH); KMCH Institute of Health Sciences and Research; Coimbatore India
| | | | | | | | - Francesco Brigo
- Department of Neurological and Movement Sciences. Section of Clinical Neurology; University of Verona; Verona Italy
| | | |
Collapse
|
7
|
Marzoog BA. Systemic and Local Hypothermia in the Context of Cell Regeneration. CRYOLETTERS 2022; 43:66-73. [PMID: 36626147 DOI: 10.54680/fr22210110112] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/06/2024]
Abstract
Local and systemic cooling is an inducer of cell proliferation. Cell proliferation and transdifferentiation or stem cells differentiation involves microenvironment regulation such as temperature. Mild hypothermia downregulates the production of pro-inflammatory cytokines and reduces the immune response against pathogens. In addition, mild tissue cooling improves endothelial cell function. Endothelial cells are involved in angiogenesis during regeneration strategies; therefore, their death is catastrophic and affects regeneration, but not cell proliferation. The potential mechanism underlying the effects of local or systemic hypothermia on cell regeneration has not yet been elucidated. Hypothermia reduces the production of reactive oxygen species and organelle activity. Hypothermia therapeutic effects depends on the targeted organ, exposure duration, and hypothermia degree. Therefore, determining these factors may enhance the usage of hypothermia more effectively in regenerative medicine. The paper introduces the hypothermia role in paracrine/endocrine cell secretion, reception, and the immune state after local and systemic hypothermia application.
Collapse
|
8
|
Bothwell SW, Omileke D, Patabendige A, Spratt NJ. CSF Secretion Is Not Altered by NKCC1 Nor TRPV4 Antagonism in Healthy Rats. Brain Sci 2021; 11:brainsci11091117. [PMID: 34573139 PMCID: PMC8471756 DOI: 10.3390/brainsci11091117] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 08/20/2021] [Accepted: 08/22/2021] [Indexed: 11/16/2022] Open
Abstract
Background: Cerebrospinal fluid (CSF) secretion can be targeted to reduce elevated intracranial pressure (ICP). Sodium-potassium-chloride cotransporter 1 (NKCC1) antagonism is used clinically. However, supporting evidence is limited. The transient receptor potential vanilloid-4 (TRPV4) channel may also regulate CSF secretion and ICP elevation. We investigated whether antagonism of these proteins reduces CSF secretion. Methods: We quantified CSF secretion rates in male Wistar rats. The cerebral aqueduct was blocked with viscous mineral oil, and a lateral ventricle was cannulated. Secretion rate was measured at baseline and after antagonist administration. Acetazolamide was administered as a positive control to confirm changes in CSF secretion rates. Results: Neither NKCC1, nor TRPV4 antagonism altered CSF secretion rate from baseline, n = 3, t(2) = 1.14, p = 0.37, and n = 4, t(3) = 0.58, p = 0.6, respectively. Acetazolamide reduced CSF secretion by ~50% across all groups, n = 7, t(6) = 4.294, p = 0.005. Conclusions: Acute antagonism of NKCC1 and TRPV4 proteins at the choroid plexus does not reduce CSF secretion in healthy rats. Further investigation of protein changes and antagonism should be explored in neurological disease where increased CSF secretion and ICP are observed before discounting the therapeutic potential of protein antagonism at these sites.
Collapse
Affiliation(s)
- Steven W. Bothwell
- The School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW 2308, Australia; (S.W.B.); (D.O.)
- Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia
| | - Daniel Omileke
- The School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW 2308, Australia; (S.W.B.); (D.O.)
- Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia
| | - Adjanie Patabendige
- The School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW 2308, Australia; (S.W.B.); (D.O.)
- Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia
- Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Wirral CH64 7TE, UK
- Correspondence: (A.P.); (N.J.S.)
| | - Neil J. Spratt
- The School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW 2308, Australia; (S.W.B.); (D.O.)
- Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia
- Hunter New England Local Health District, New Lambton Heights, NSW 2305, Australia
- Correspondence: (A.P.); (N.J.S.)
| |
Collapse
|
9
|
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.
Collapse
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
| |
Collapse
|
10
|
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.
Collapse
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
| |
Collapse
|
11
|
Neuroprotective Effects of Lacosamide and Memantine on Hyperoxic Brain Injury in Rats. Neurochem Res 2020; 45:1920-1929. [PMID: 32444924 DOI: 10.1007/s11064-020-03056-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Revised: 05/12/2020] [Accepted: 05/16/2020] [Indexed: 10/24/2022]
Abstract
In neonates supraphysiological oxygen therapy has been demonstrated to cause neuronal death in hippocampus, prefrontal cortex, parietal cortex, and retrosplenial cortex. There is a need for the detection of novel neuroprotective drugs. Neuroprotective effects of lacosamide or memantine have been demonstrated in adult patients with ischemia, trauma and status epilepticus. The effects in immature brains may be different. This study aimed to evaluate neuroprotective effects of lacosamide and memantine treatment in a hyperoxia-induced brain injury model in immature rats. This study was performed in the Animal Experiments Laboratory of Dokuz Eylul University Faculty of Medicine. Neonatal Wistar strain rat pups were exposed to hyperoxia (80% oxygen + 20% nitrogen) for five days postnatally. They were divided into five groups; hyperoxia + lacosamide, hyperoxia + memantine, hyperoxia + lacosamide and memantine, hyperoxia + saline, control groups. After termination of the experiment, brain tissues were examined. Neuron counting in examined regions were found to be higher in hyperoxia + memantine and hyperoxia + lacosamide and memantine groups than hyperoxia + saline group. The presence of apoptotic cells evaluated with TUNEL and active Caspase-3 in hyperoxia + memantine and hyperoxia + lacosamide and memantine groups were found to be lower compared to hyperoxia + saline group. This study demonstrates that neuron death and apoptosis in newborn rat brains after hyperoxia is reduced upon memantine treatment. This is the first study to show the effects of memantine and lacosamide on hyperoxia-induced damage in neonatal rat brains.
Collapse
|
12
|
Tao D, Liu F, Sun X, Qu H, Zhao S, Zhou Z, Xiao T, Zhao C, Zhao M. Bumetanide: A review of its neuroplasticity and behavioral effects after stroke. Restor Neurol Neurosci 2020; 37:397-407. [PMID: 31306143 DOI: 10.3233/rnn-190926] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Stroke often leads to neuronal injury and neurological functional deficits. Whilst spontaneous neurogenesis and axon regeneration are induced by ischemic stroke, effective pharmacological treatments are also essential for the improvement of neuroplasticity and functional recovery after stroke. However, no pharmacological therapy has been demonstrated to be able to effectively improve the functional recovery after stroke. Bumetanide is a specific Na+-K+-Cl- co-transporter inhibitor which can maintain chloride homeostasis in neurons. Therefore, many studies have focused on this drug's effect in stroke recovery in recent years. Here, we first review the function of Na+-K+-Cl- co-transporter in neurons, then how bumetanide's role in reducing brain damage, promoting neuroplasticity, leading to functional recovery after stroke, is elucidated. Finally, we discuss current limitations of bumetanide's efficiency and their potential solutions. These results may provide new avenues for further exploring mechanisms of post-stroke functional recovery as well as promising therapeutic targets for functional disability rehabilitation after ischemic stroke.
Collapse
Affiliation(s)
- Dongxia Tao
- Neurology, The First Hospital of China Medical University, Shenyang, China
| | - Fangxi Liu
- Neurology, The First Hospital of China Medical University, Shenyang, China
| | - Xiaoyu Sun
- Neurology, The People's Hospital of Liaoning Province, Shenyang, China
| | - Huiling Qu
- Neurology, The People's Hospital of Liaoning Province, Shenyang, China
| | - Shanshan Zhao
- Neurology, The First Hospital of China Medical University, Shenyang, China
| | - Zhike Zhou
- Geriatrics, The First Hospital of China Medical University, Shenyang, China
| | - Ting Xiao
- Dermatology, The First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Immunodermatology, Ministry of Health, Ministry of Education, Shenyang, China
| | - Chuansheng Zhao
- Neurology, The First Hospital of China Medical University, Shenyang, China
| | - Mei Zhao
- Cardiology, The Shengjing Affiliated Hospital, China Medical University, Shenyang, China
| |
Collapse
|
13
|
Sun YJ, Zhang ZY, Fan B, Li GY. Neuroprotection by Therapeutic Hypothermia. Front Neurosci 2019; 13:586. [PMID: 31244597 PMCID: PMC6579927 DOI: 10.3389/fnins.2019.00586] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Accepted: 05/23/2019] [Indexed: 12/14/2022] Open
Abstract
Hypothermia therapy is an old and important method of neuroprotection. Until now, many neurological diseases such as stroke, traumatic brain injury, intracranial pressure elevation, subarachnoid hemorrhage, spinal cord injury, hepatic encephalopathy, and neonatal peripartum encephalopathy have proven to be suppressed by therapeutic hypothermia. Beneficial effects of therapeutic hypothermia have also been discovered, and progress has been made toward improving the benefits of therapeutic hypothermia further through combination with other neuroprotective treatments and by probing the mechanism of hypothermia neuroprotection. In this review, we compare different hypothermia induction methods and provide a summarized account of the synergistic effect of hypothermia therapy with other neuroprotective treatments, along with an overview of hypothermia neuroprotection mechanisms and cold/hypothermia-induced proteins.
Collapse
Affiliation(s)
- Ying-Jian Sun
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun, China
| | - Zi-Yuan Zhang
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun, China
| | - Bin Fan
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun, China
| | - Guang-Yu Li
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun, China
| |
Collapse
|
14
|
Davidson JO, Bennet L, Gunn AJ. Evaluating anti-epileptic drugs in the era of therapeutic hypothermia. Pediatr Res 2019; 85:931-933. [PMID: 30742031 DOI: 10.1038/s41390-019-0319-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 01/09/2019] [Accepted: 01/21/2019] [Indexed: 11/09/2022]
Affiliation(s)
- Joanne O Davidson
- The Department of Physiology, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
| | - Laura Bennet
- The Department of Physiology, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
| | - Alistair J Gunn
- The Department of Physiology, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand.
| |
Collapse
|
15
|
Sudhakar SK, Choi TJ, Ahmed OJ. Biophysical Modeling Suggests Optimal Drug Combinations for Improving the Efficacy of GABA Agonists after Traumatic Brain Injuries. J Neurotrauma 2019; 36:1632-1645. [PMID: 30484362 PMCID: PMC6531909 DOI: 10.1089/neu.2018.6065] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Traumatic brain injuries (TBI) lead to dramatic changes in the surviving brain tissue. Altered ion concentrations, coupled with changes in the expression of membrane-spanning proteins, create a post-TBI brain state that can lead to further neuronal loss caused by secondary excitotoxicity. Several GABA receptor agonists have been tested in the search for neuroprotection immediately after an injury, with paradoxical results. These drugs not only fail to offer neuroprotection, but can also slow down functional recovery after TBI. Here, using computational modeling, we provide a biophysical hypothesis to explain these observations. We show that the accumulation of intracellular chloride ions caused by a transient upregulation of Na+-K+-2Cl- (NKCC1) co-transporters as observed following TBI, causes GABA receptor agonists to lead to excitation and depolarization block, rather than the expected hyperpolarization. The likelihood of prolonged, excitotoxic depolarization block is further exacerbated by the extremely high levels of extracellular potassium seen after TBI. Our modeling results predict that the neuroprotective efficacy of GABA receptor agonists can be substantially enhanced when they are combined with NKCC1 co-transporter inhibitors. This suggests a rational, biophysically principled method for identifying drug combinations for neuroprotection after TBI.
Collapse
Affiliation(s)
| | - Thomas J. Choi
- Department of Psychology, University of Michigan, Ann Arbor, Michigan
| | - Omar J. Ahmed
- Department of Psychology, University of Michigan, Ann Arbor, Michigan
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
- Department of Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan
- Department of Kresge Hearing Research Institute, University of Michigan, Ann Arbor, Michigan
- Department of Michigan Center for Integrative Research in Critical Care, University of Michigan, Ann Arbor, Michigan
| |
Collapse
|
16
|
Kharod SC, Kang SK, Kadam SD. Off-Label Use of Bumetanide for Brain Disorders: An Overview. Front Neurosci 2019; 13:310. [PMID: 31068771 PMCID: PMC6491514 DOI: 10.3389/fnins.2019.00310] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 03/19/2019] [Indexed: 01/17/2023] Open
Abstract
Bumetanide (BTN or BUM) is a FDA-approved potent loop diuretic (LD) that acts by antagonizing sodium-potassium-chloride (Na-K-Cl) cotransporters, NKCC1 (SLc12a2) and NKCC2. While NKCC1 is expressed both in the CNS and in systemic organs, NKCC2 is kidney-specific. The off-label use of BTN to modulate neuronal transmembrane Cl− gradients by blocking NKCC1 in the CNS has now been tested as an anti-seizure agent and as an intervention for neurological disorders in pre-clinical studies with varying results. BTN safety and efficacy for its off-label use has also been tested in several clinical trials for neonates, children, adolescents, and adults. It failed to meet efficacy criteria for hypoxic-ischemic encephalopathy (HIE) neonatal seizures. In contrast, positive outcomes in temporal lobe epilepsy (TLE), autism, and schizophrenia trials have been attributed to BTN in studies evaluating its off-label use. NKCC1 is an electroneutral neuronal Cl− importer and the dominance of NKCC1 function has been proposed as the common pathology for HIE seizures, TLE, autism, and schizophrenia. Therefore, the use of BTN to antagonize neuronal NKCC1 with the goal to lower internal Cl− levels and promote GABAergic mediated hyperpolarization has been proposed. In this review, we summarize the data and results for pre-clinical and clinical studies that have tested off-label BTN interventions and report variable outcomes. We also compare the data underlying the developmental expression profile of NKCC1 and KCC2, highlight the limitations of BTN’s brain-availability and consider its actions on non-neuronal cells.
Collapse
Affiliation(s)
- Shivani C Kharod
- Neuroscience Laboratory, Hugo W. Moser Research Institute at Kennedy Krieger, Baltimore, MD, United States
| | - Seok Kyu Kang
- Neuroscience Laboratory, Hugo W. Moser Research Institute at Kennedy Krieger, Baltimore, MD, United States
| | - Shilpa D Kadam
- Neuroscience Laboratory, Hugo W. Moser Research Institute at Kennedy Krieger, Baltimore, MD, United States.,Department of Neurology and Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| |
Collapse
|
17
|
Brandt C, Seja P, Töllner K, Römermann K, Hampel P, Kalesse M, Kipper A, Feit PW, Lykke K, Toft-Bertelsen TL, Paavilainen P, Spoljaric I, Puskarjov M, MacAulay N, Kaila K, Löscher W. Bumepamine, a brain-permeant benzylamine derivative of bumetanide, does not inhibit NKCC1 but is more potent to enhance phenobarbital's anti-seizure efficacy. Neuropharmacology 2018; 143:186-204. [DOI: 10.1016/j.neuropharm.2018.09.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 08/30/2018] [Accepted: 09/16/2018] [Indexed: 01/01/2023]
|
18
|
Abstract
Neonatal seizures constitute the most frequent presenting neurologic sign encountered in the neonatal intensive care unit. Despite limited efficacy and safety data, phenobarbital continues to be used near-universally as the first-line anti-seizure drug (ASD) in neonates. The choice of second-line ASDs varies by provider and institution, and is still not supported by sufficient scientific evidence. In this review, we discuss the available evidence supporting the efficacy, mechanism of action, potential adverse effects, key pharmacokinetic characteristics such as interaction with therapeutic hypothermia, logistical issues, and rationale for use of neonatal ASDs. We describe the widely used neonatal ASDs, namely phenobarbital, phenytoin, midazolam, and levetiracetam, in addition to potential ASDs, including lidocaine, topiramate, and bumetanide.
Collapse
Affiliation(s)
- Mohamed El-Dib
- Neonatal Neurocritical Care, Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Janet S Soul
- Fetal-Neonatal Neurology Program, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
19
|
Effects of therapeutic hypothermia on white matter injury from murine neonatal hypoxia-ischemia. Pediatr Res 2017; 82:518-526. [PMID: 28561815 PMCID: PMC5570671 DOI: 10.1038/pr.2017.75] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 03/06/2017] [Indexed: 12/20/2022]
Abstract
BackgroundTherapeutic hypothermia (TH) is the standard of care for neonates with hypoxic-ischemic encephalopathy, but it is not fully protective in the clinical setting. Hypoxia-ischemia (HI) may cause white matter injury (WMI), leading to neurological and cognitive dysfunction.MethodsP9 mice were subjected to HI as previously described. Pups underwent 3.5 h of systemic hypothermia or normothermia. Cresyl violet and Perl's iron staining for histopathological scoring of brain sections was completed blindly on all brains. Immunocytochemical (ICC) staining for myelin basic protein (MBP), microglia (Iba1), and astrocytes (glia fibrillary acidic protein (GFAP)) was performed on adjacent sections. Volumetric measurements of MBP coverage were used for quantitative analysis of white matter.ResultsTH provided neuroprotection by injury scoring for the entire group (n=44; P<0.0002). ICC analysis of a subset of brains showed that the lateral caudate was protected from WMI (P<0.05). Analysis revealed decreased GFAP and Iba1 staining in hippocampal regions, mostly CA2/CA3. GFAP and Iba1 directly correlated with injury scores of normothermic brains.ConclusionTH reduced injury, and qualitative data suggest that hippocampus and lateral caudate are protected from HI. Mildly injured brains may better show the benefits of TH. Overall, these data indicate regional differences in WMI susceptibility and inflammation in a P9 murine HI model.
Collapse
|
20
|
Lowe DW, Fraser JL, Rollins LG, Bentzley J, Nie X, Martin R, Singh I, Jenkins D. Vitamin D improves functional outcomes in neonatal hypoxic ischemic male rats treated with N-acetylcysteine and hypothermia. Neuropharmacology 2017; 123:186-200. [PMID: 28599922 DOI: 10.1016/j.neuropharm.2017.06.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 04/21/2017] [Accepted: 06/05/2017] [Indexed: 12/29/2022]
Abstract
Hypothermia treatment neuroprotects approximately 50% of neonates who present with moderate to severe hypoxic ischemic encephalopathy (HIE). N-acetylcysteine (NAC), a potent antioxidant, is neuroprotective in combination with hypothermia in neonatal hypoxia-ischemia (HI) female rats, but less protective in males. Vitamin D is a neurosteroid, which may provide immunomodulation and improve outcomes for both sexes. We investigated the efficacy of this combination of drugs with hypothermia after severe HI, as well as potential mechanisms of vitamin D effects in the transition to chronic inflammation. DOL 7 rats were randomized to sham, or HI and hypothermia treated with either saline (HYPO), NAC (50 mg/kg/d, HNAC), or HNAC plus 1,25-dihydroxy-vitamin D3 (0.1 μg/kg/d, HNAC + VitD) daily for 2 weeks. A second set of animals were randomized and treated for 11 days to investigate vitamin D metabolism and inflammatory mediators. Rats treated with HNAC + VitD performed significantly better on tests of strength and use of affected limb, adaptive sensorimotor skills, motor sequence learning, and working memory than either HYPO or HNAC, particularly benefiting male rats. Significantly fewer rats in the HNAC + VitD group had severe hemispheric volume loss. HI injury decreased serum vitamin D at 11 days and induced the enzyme that deactivates vitamin D in the hippocampus, particularly in males. Persistent vitamin D dysregulation was seen in both hippocampi in males, which was not reversed by hypothermia. Vitamin D in combination with hypothermia and NAC supports functional recovery in both sexes of neonatal rats significantly better than hypothermia alone or hypothermia and NAC in this severe HI model.
Collapse
Affiliation(s)
- Danielle W Lowe
- Department of Pediatrics, Medical University of South Carolina, Charleston, SC, United States.
| | - Jamie L Fraser
- Division of Genetics and Metabolism, Children's National Medical Center, Washington, DC, United States.
| | - Laura Grace Rollins
- Department of Psychology, University of Massachusetts, Boston, MA, United States.
| | - Jessica Bentzley
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, United States.
| | - Xingju Nie
- Department of Radiology, Medical University of South Carolina, Charleston, SC, United States.
| | - Renee Martin
- Department of Public Health, Medical University of South Carolina, Charleston, SC, United States.
| | - Inderjit Singh
- Department of Pediatrics, Medical University of South Carolina, Charleston, SC, United States.
| | - Dorothea Jenkins
- Department of Pediatrics, Medical University of South Carolina, Charleston, SC, United States.
| |
Collapse
|
21
|
Glykys J, Dzhala V, Egawa K, Kahle KT, Delpire E, Staley K. Chloride Dysregulation, Seizures, and Cerebral Edema: A Relationship with Therapeutic Potential. Trends Neurosci 2017; 40:276-294. [PMID: 28431741 DOI: 10.1016/j.tins.2017.03.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 03/22/2017] [Accepted: 03/23/2017] [Indexed: 11/18/2022]
Abstract
Pharmacoresistant seizures and cytotoxic cerebral edema are serious complications of ischemic and traumatic brain injury. Intraneuronal Cl- concentration ([Cl-]i) regulation impacts on both cell volume homeostasis and Cl--permeable GABAA receptor-dependent membrane excitability. Understanding the pleiotropic molecular determinants of neuronal [Cl-]i - cytoplasmic impermeant anions, polyanionic extracellular matrix (ECM) glycoproteins, and plasmalemmal Cl- transporters - could help the identification of novel anticonvulsive and neuroprotective targets. The cation/Cl- cotransporters and ECM metalloproteinases may be particularly druggable targets for intervention. We establish here a paradigm that accounts for recent data regarding the complex regulatory mechanisms of neuronal [Cl-]i and how these mechanisms impact on neuronal volume and excitability. We propose approaches to modulate [Cl-]i that are relevant for two common clinical sequela of brain injury: edema and seizures.
Collapse
Affiliation(s)
- Joseph Glykys
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Medical School, Boston, MA 02115, USA.
| | - Volodymyr Dzhala
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Kiyoshi Egawa
- Department of Pediatrics, Hokkaido University Hospital, Sapporo 0010019, Japan
| | - Kristopher T Kahle
- Departments of Neurosurgery, Pediatrics, and Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Eric Delpire
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Kevin Staley
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
22
|
Barks JD, Liu Y, Shangguan Y, Djuric Z, Ren J, Silverstein FS. Maternal high-fat diet influences outcomes after neonatal hypoxic-ischemic brain injury in rodents. J Cereb Blood Flow Metab 2017; 37:307-318. [PMID: 26738750 PMCID: PMC5363747 DOI: 10.1177/0271678x15624934] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 11/25/2015] [Accepted: 12/07/2015] [Indexed: 12/17/2022]
Abstract
The typical US diet has >30% calories from fat; yet, typical laboratory diets contain 17% calories from fat. This disparity could confound the clinical relevance of findings in cerebral ischemia models. We compared outcomes after neonatal brain injury in offspring of rat dams fed standard low-fat chow (17% fat calories) or a higher fat diet (34% fat calories) from day 7 of pregnancy. On postnatal day 7, hypoxic-ischemic injury was induced by right carotid ligation, followed by 60, 75 or 90 min 8% oxygen exposure. Sensorimotor function, brain damage, and serum and brain fatty acid content were compared 1 to 4 weeks later. All lesioned animals developed left forepaw placing deficits; scores were worse in the high-fat groups (p < 0.0001, ANOVA). Similarly, reductions in left forepaw grip strength were more pronounced in the high-fat groups. Severity of right hemisphere damage increased with hypoxia-ischemia duration but did not differ between diet groups. Serum and brain docosahexaenoic acid fatty acid fractions were lower in high-fat progeny (p < 0.05, ANOVA). We speculate that the high-fat diet disrupted docosahexaenoic acid-dependent recovery mechanisms. These findings have significant implications both for refinement of neonatal brain injury models and for understanding the impact of maternal diet on neonatal neuroplasticity.
Collapse
Affiliation(s)
- John D Barks
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Yiqing Liu
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Yu Shangguan
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Zora Djuric
- Department of Family Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Jianwei Ren
- Department of Family Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Faye S Silverstein
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA.,Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
23
|
Treatment temperature and insult severity influence the neuroprotective effects of therapeutic hypothermia. Sci Rep 2016; 6:23430. [PMID: 26997257 PMCID: PMC4800445 DOI: 10.1038/srep23430] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 02/22/2016] [Indexed: 12/20/2022] Open
Abstract
Therapeutic hypothermia (HT) is standard care for moderate and severe neonatal hypoxic-ischaemic encephalopathy (HIE), the leading cause of permanent brain injury in term newborns. However, the optimal temperature for HT is still unknown, and few preclinical studies have compared multiple HT treatment temperatures. Additionally, HT may not benefit infants with severe encephalopathy. In a neonatal rat model of unilateral hypoxia-ischaemia (HI), the effect of five different HT temperatures was investigated after either moderate or severe injury. At postnatal-day seven, rat pups underwent moderate or severe HI followed by 5 h at normothermia (37 °C), or one of five HT temperatures: 33.5 °C, 32 °C, 30 °C, 26 °C, and 18 °C. One week after treatment, neuropathological analysis of hemispheric and hippocampal area loss, and CA1 hippocampal pyramidal neuron count, was performed. After moderate injury, a significant reduction in hemispheric and hippocampal loss on the injured side, and preservation of CA1 pyramidal neurons, was seen in the 33.5 °C, 32 °C, and 30 °C groups. Cooling below 33.5 °C did not provide additional neuroprotection. Regardless of treatment temperature, HT was not neuroprotective in the severe HI model. Based on these findings, and previous experience translating preclinical studies into clinical application, we propose that milder cooling should be considered for future clinical trials.
Collapse
|
24
|
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.
Collapse
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
| |
Collapse
|
25
|
Nie X, Lowe DW, Rollins LG, Bentzley J, Fraser JL, Martin R, Singh I, Jenkins D. Sex-specific effects of N-acetylcysteine in neonatal rats treated with hypothermia after severe hypoxia-ischemia. Neurosci Res 2016; 108:24-33. [PMID: 26851769 DOI: 10.1016/j.neures.2016.01.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 12/16/2015] [Accepted: 01/24/2016] [Indexed: 12/29/2022]
Abstract
Approximately half of moderate to severely hypoxic-ischemic (HI) newborns do not respond to hypothermia, the only proven neuroprotective treatment. N-acetylcysteine (NAC), an antioxidant and glutathione precursor, shows promise for neuroprotection in combination with hypothermia, mitigating post-HI neuroinflammation due to oxidative stress. As mechanisms of HI injury and cell death differ in males and females, sex differences must be considered in translational research of neuroprotection. We assessed the potential toxicity and efficacy of NAC in combination with hypothermia, in male and female neonatal rats after severe HI injury. NAC 50mg/kg/d administered 1h after initiation of hypothermia significantly decreased iNOS expression and caspase 3 activation in the injured hemisphere versus hypothermia alone. However, only females treated with hypothermia +NAC 50mg/kg showed improvement in short-term infarct volumes compared with saline treated animals. Hypothermia alone had no effect in this severe model. When NAC was continued for 6 weeks, significant improvement in long-term neuromotor outcomes over hypothermia treatment alone was observed, controlling for sex. Antioxidants may provide insufficient neuroprotection after HI for neonatal males in the short term, while long-term therapy may benefit both sexes.
Collapse
Affiliation(s)
- Xingju Nie
- Center for Biomedical Imaging, Medical University of South Carolina, 165 Ashley Ave, Charleston, SC 29425, United States.
| | - Danielle W Lowe
- Department of Pediatrics, Medical University of South Carolina, 165 Ashley Ave, Charleston, SC 29425, United States.
| | - Laura Grace Rollins
- Department of Psychology, University of Massachusetts, 100 Morrissey Blvd, Boston, MA 02125, United States.
| | - Jessica Bentzley
- Department of Pediatrics, Medical University of South Carolina, 165 Ashley Ave, Charleston, SC 29425, United States.
| | - Jamie L Fraser
- Medical Genetics Training Program, National Human Genome Research Institute, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892-2152, United States.
| | - Renee Martin
- Department of Biostatistics and Epidemiology, Medical University of South Carolina, 165 Ashley Ave, Charleston, SC 29425, United States.
| | - Inderjit Singh
- Department of Pediatrics, Medical University of South Carolina, 165 Ashley Ave, Charleston, SC 29425, United States.
| | - Dorothea Jenkins
- Department of Pediatrics, Medical University of South Carolina, 165 Ashley Ave, Charleston, SC 29425, United States.
| |
Collapse
|
26
|
In vitro bidirectional permeability studies identify pharmacokinetic limitations of NKCC1 inhibitor bumetanide. Eur J Pharmacol 2016; 770:117-25. [DOI: 10.1016/j.ejphar.2015.12.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 11/25/2015] [Accepted: 12/01/2015] [Indexed: 12/31/2022]
|
27
|
Wang B, Armstrong JS, Reyes M, Kulikowicz E, Lee JH, Spicer D, Bhalala U, Yang ZJ, Koehler RC, Martin LJ, Lee JK. White matter apoptosis is increased by delayed hypothermia and rewarming in a neonatal piglet model of hypoxic ischemic encephalopathy. Neuroscience 2015; 316:296-310. [PMID: 26739327 DOI: 10.1016/j.neuroscience.2015.12.046] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 10/12/2015] [Accepted: 12/24/2015] [Indexed: 11/29/2022]
Abstract
Therapeutic hypothermia is widely used to treat neonatal hypoxic ischemic (HI) brain injuries. However, potentially deleterious effects of delaying the induction of hypothermia and of rewarming on white matter injury remain unclear. We used a piglet model of HI to assess the effects of delayed hypothermia and rewarming on white matter apoptosis. Piglets underwent HI injury or sham surgery followed by normothermic or hypothermic recovery at 2h. Hypothermic groups were divided into those with no rewarming, slow rewarming at 0.5°C/h, or rapid rewarming at 4°C/h. Apoptotic cells in the subcortical white matter of the motor gyrus, corpus callosum, lateral olfactory tract, and internal capsule at 29h were identified morphologically and counted by hematoxylin & eosin staining. Cell death was verified by terminal deoxynucleotidyl transferase (TdT) dUTP nick end labeling (TUNEL) assay. White matter neurons were also counted, and apoptotic cells were immunophenotyped with the oligodendrocyte marker 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNPase). Hypothermia, slow rewarming, and rapid rewarming increased apoptosis in the subcortical white matter relative to normothermia (p<0.05). The number of white matter neurons was not lower in groups with more apoptosis after hypothermia or rapid rewarming, indicating that the apoptosis occurred among glial cells. Hypothermic piglets had more apoptosis in the lateral olfactory tract than those that were rewarmed (p<0.05). The promotion of apoptosis by hypothermia and rewarming in these regions was independent of HI. In the corpus callosum, HI piglets had more apoptosis than shams after normothermia, slow rewarming, and rapid rewarming (p<0.05). Many apoptotic cells were myelinating oligodendrocytes identified by CNPase positivity. Our results indicate that delaying the induction of hypothermia and rewarming are associated with white matter apoptosis in a piglet model of HI; in some regions these temperature effects are independent of HI. Vulnerable cells include myelinating oligodendrocytes. This study identifies a deleterious effect of therapeutic hypothermia in the developing brain.
Collapse
Affiliation(s)
- B Wang
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD (JHU), United States
| | - J S Armstrong
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD (JHU), United States
| | - M Reyes
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD (JHU), United States
| | - E Kulikowicz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD (JHU), United States
| | - J-H Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD (JHU), United States
| | - D Spicer
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD (JHU), United States
| | - U Bhalala
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD (JHU), United States
| | - Z-J Yang
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD (JHU), United States
| | - R C Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD (JHU), United States
| | - L J Martin
- Department of Pathology, Division of Neuropathology, JHU, United States
| | - J K Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD (JHU), United States.
| |
Collapse
|
28
|
Marguet SL, Le-Schulte VTQ, Merseburg A, Neu A, Eichler R, Jakovcevski I, Ivanov A, Hanganu-Opatz IL, Bernard C, Morellini F, Isbrandt D. Treatment during a vulnerable developmental period rescues a genetic epilepsy. Nat Med 2015; 21:1436-44. [PMID: 26594844 DOI: 10.1038/nm.3987] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 10/09/2015] [Indexed: 12/14/2022]
Abstract
The nervous system is vulnerable to perturbations during specific developmental periods. Insults during such susceptible time windows can have long-term consequences, including the development of neurological diseases such as epilepsy. Here we report that a pharmacological intervention timed during a vulnerable neonatal period of cortical development prevents pathology in a genetic epilepsy model. By using mice with dysfunctional Kv7 voltage-gated K(+) channels, which are mutated in human neonatal epilepsy syndromes, we demonstrate the safety and efficacy of the sodium-potassium-chloride cotransporter NKCC1 antagonist bumetanide, which was administered during the first two postnatal weeks. In Kv7 current-deficient mice, which normally display epilepsy, hyperactivity and stereotypies as adults, transient bumetanide treatment normalized neonatal in vivo cortical network and hippocampal neuronal activity, prevented structural damage in the hippocampus and restored wild-type adult behavioral phenotypes. Furthermore, bumetanide treatment did not adversely affect control mice. These results suggest that in individuals with disease susceptibility, timing prophylactically safe interventions to specific windows during development may prevent or arrest disease progression.
Collapse
Affiliation(s)
- Stephan Lawrence Marguet
- Experimental Neurophysiology, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Institute for Molecular and Behavioral Neuroscience, University of Cologne, Cologne, Germany.,Experimental Neuropediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Andrea Merseburg
- Experimental Neurophysiology, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Institute for Molecular and Behavioral Neuroscience, University of Cologne, Cologne, Germany.,Experimental Neuropediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Axel Neu
- Experimental Neuropediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ronny Eichler
- Experimental Neuropediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Igor Jakovcevski
- Experimental Neurophysiology, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Institute for Molecular and Behavioral Neuroscience, University of Cologne, Cologne, Germany
| | - Anton Ivanov
- Aix Marseille Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Institut de Neurosciences des Systèmes (INS), Unité Mixte de Recherche (UMR) S1106, Marseille, France
| | - Ileana Livia Hanganu-Opatz
- Developmental Neurophysiology, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christophe Bernard
- Aix Marseille Université, Institut National de la Santé et de la Recherche Médicale (INSERM), Institut de Neurosciences des Systèmes (INS), Unité Mixte de Recherche (UMR) S1106, Marseille, France
| | - Fabio Morellini
- Experimental Neuropediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Behavioral Biology Unit, Center for Molecular Neurobiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Dirk Isbrandt
- Experimental Neurophysiology, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Institute for Molecular and Behavioral Neuroscience, University of Cologne, Cologne, Germany.,Experimental Neuropediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| |
Collapse
|
29
|
Glykys J, Staley KJ. Diazepam effect during early neonatal development correlates with neuronal Cl(.). Ann Clin Transl Neurol 2015; 2:1055-70. [PMID: 26734658 PMCID: PMC4693588 DOI: 10.1002/acn3.259] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 09/16/2015] [Indexed: 11/09/2022] Open
Abstract
Objective Although benzodiazepines and other GABAA receptors allosteric modulators are used to treat neonatal seizures, their efficacy may derive from actions on subcortical structures. Side effects of benzodiazepines in nonseizing human neonates include myoclonus, seizures, and abnormal movements. Excitatory actions of GABA may underlie both side effects and reduced anticonvulsant activity of benzodiazepines. Neocortical organotypic slice cultures were used to study: (1) spontaneous cortical epileptiform activity during early development; (2) developmental changes in [Cl−]i and (3) whether diazepam's anticonvulsant effect correlated with neuronal [Cl−]i. Methods Epileptiform activity in neocortical organotypic slice cultures was measured by field potential recordings. Cl− changes during development were assessed by multiphoton imaging of neurons transgenically expressing a Cl‐sensitive fluorophore. Clinically relevant concentrations of diazepam were used to test the anticonvulsant effectiveness at ages corresponding to premature neonates through early infancy. Results (1) Neocortical organotypic slices at days in vitro 5 (DIV5) exhibited spontaneous epileptiform activity. (2) Epileptiform event duration decreased with age. (3) There was a progressive decrease in [Cl−]i over the same age range. (4) Diazepam was ineffective in decreasing epileptiform activity at DIV5‐6, but progressively more effective at older ages through DIV15. (5) At DIV5‐6, diazepam worsened epileptiform activity in 50% of the slices. Interpretation The neocortical organotypic slice is a useful model to study spontaneous epileptiform activity. Decreasing [Cl−]i during development correlates with decreasing duration of spontaneous epileptiform activity and increasing anticonvulsant efficacy of diazepam. We provide a potential explanation for the reports of seizures and myoclonus induction by benzodiazepines in newborn human neonates and the limited electrographic efficacy of benzodiazepines for the treatment of neonatal seizures.
Collapse
Affiliation(s)
- Joseph Glykys
- Department of Neurology Massachusetts General Hospital Boston Massachusetts; Harvard Medical School Boston Massachusetts
| | - Kevin J Staley
- Department of Neurology Massachusetts General Hospital Boston Massachusetts; Harvard Medical School Boston Massachusetts
| |
Collapse
|
30
|
Rewarming from therapeutic hypothermia induces cortical neuron apoptosis in a swine model of neonatal hypoxic-ischemic encephalopathy. J Cereb Blood Flow Metab 2015; 35:781-93. [PMID: 25564240 PMCID: PMC4420851 DOI: 10.1038/jcbfm.2014.245] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 12/05/2014] [Accepted: 12/08/2014] [Indexed: 11/08/2022]
Abstract
The consequences of therapeutic hypothermia for neonatal hypoxic-ischemic encephalopathy are poorly understood. Adverse effects from suboptimal rewarming could diminish neuroprotection from hypothermia. Therefore, we tested whether rewarming is associated with apoptosis. Piglets underwent hypoxia-asphyxia followed by normothermic or hypothermic recovery at 2 hours. Hypothermic groups were divided into those with no rewarming, rewarming at 0.5 °C/hour, or rewarming at 4 °C/hour. Neurodegeneration at 29 hours was assessed by hematoxylin and eosin staining, TUNEL assay, and immunoblotting for cleaved caspase-3. Rewarmed piglets had more apoptosis in motor cortex than did those that remained hypothermic after hypoxia-asphyxia. Apoptosis in piriform cortex was greater in hypoxic-asphyxic, rewarmed piglets than in naive/sham piglets. Caspase-3 inhibitor suppressed apoptosis with rewarming. Rapidly rewarmed piglets had more caspase-3 cleavage in cerebral cortex than did piglets that remained hypothermic or piglets that were rewarmed slowly. We conclude that rewarming from therapeutic hypothermia can adversely affect the newborn brain by inducing apoptosis through caspase mechanisms.
Collapse
|
31
|
Jantzie LL, Hu MY, Park HK, Jackson MC, Yu J, Maxwell JR, Jensen FE. Chloride cotransporter NKCC1 inhibitor bumetanide protects against white matter injury in a rodent model of periventricular leukomalacia. Pediatr Res 2015; 77:554-62. [PMID: 25585037 DOI: 10.1038/pr.2015.9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 10/25/2014] [Indexed: 01/19/2023]
Abstract
BACKGROUND Periventricular leukomalacia (PVL) is a major form of preterm brain injury. Na(+)-K(+)-Cl(-) 1 cotransporter (NKCC1) expression on neurons and astrocytes is developmentally regulated and mediates Cl(-) reversal potential. We hypothesized that NKCC1 is highly expressed on oligodendrocytes (OLs) and increases vulnerability to hypoxia-ischemia (HI) mediated white matter injury, and that the NKCC1 inhibitor bumetanide would be protective in a rodent PVL model. METHODS Immunohistochemistry in Long-Evans rats and PLP-EGFP transgenic mice was used to establish cell-specific expression of NKCC1 in the immature rodent brain. HI was induced on postnatal day 6 (P6) in rats and the protective efficacy of bumetanide (0.3 mg/kg/i.p. q12h × 60 h) established. RESULTS NKCC1 was expressed on OLs and subplate neurons through the first 2 postnatal weeks, peaking in white matter and the subplate between P3-7. Following HI, NKCC1 is expressed on OLs and neurons. Bumetanide treatment significantly attenuates myelin basic protein loss and neuronal degeneration 7 d post-HI. CONCLUSION Presence and relative overexpression of NKCC1 in rodent cerebral cortex coincides with a period of developmental vulnerability to HI white matter injury in the immature prenatal brain. The protective efficacy of bumetanide in this model of preterm brain injury suggests that Cl(-) transport is a factor in PVL and that its inhibition may have clinical application in premature human infants.
Collapse
Affiliation(s)
- Lauren L Jantzie
- 1] Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts [2] Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Melody Y Hu
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Hyun-Kyung Park
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Michele C Jackson
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Jenny Yu
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Jessie R Maxwell
- Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Frances E Jensen
- 1] Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts [2] Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| |
Collapse
|
32
|
Bialer M, Johannessen SI, Levy RH, Perucca E, Tomson T, White HS. Progress report on new antiepileptic drugs: A summary of the Twelfth Eilat Conference (EILAT XII). Epilepsy Res 2015; 111:85-141. [PMID: 25769377 DOI: 10.1016/j.eplepsyres.2015.01.001] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 01/09/2015] [Indexed: 10/24/2022]
|
33
|
Yang D, Kuan CY. Anti-tissue plasminogen activator (tPA) as an effective therapy of neonatal hypoxia-ischemia with and without inflammation. CNS Neurosci Ther 2014; 21:367-73. [PMID: 25475942 DOI: 10.1111/cns.12365] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 10/30/2014] [Accepted: 11/01/2014] [Indexed: 01/23/2023] Open
Abstract
Hypoxic-ischemic brain injury is an important cause of neurodevelopmental deficits in neonates. Intrauterine infection and the ensuing fetal inflammatory responses augment hypoxic-ischemic brain injury and attenuate the efficacy of therapeutic hypothermia. Here, we review evidences from preclinical studies suggesting that the induction of brain parenchymal tissue-type plasminogen activator (tPA) plays an important pathogenic role in these conditions. Moreover, administration of a stable-mutant form of plasminogen activator inhibitor-1 called CPAI confers potent protection against hypoxic-ischemic injury with and without inflammation via different mechanisms. Besides intracerebroventricular injection, CPAI can also be administered into the brain using a noninvasive intranasal delivery strategy, adding to its applicability in clinical use. In sum, the therapeutic potential of CPAI in neonatal care merits further investigation with large-animal models of hypoxia-ischemia and cerebral palsy.
Collapse
Affiliation(s)
- Dianer Yang
- Department of Pediatrics, Children's Healthcare of Atlanta; Center for Neurodegenerative Disease (CND), Emory University School of Medicine, Atlanta, GA, USA
| | | |
Collapse
|
34
|
Puskarjov M, Kahle KT, Ruusuvuori E, Kaila K. Pharmacotherapeutic targeting of cation-chloride cotransporters in neonatal seizures. Epilepsia 2014; 55:806-18. [PMID: 24802699 PMCID: PMC4284054 DOI: 10.1111/epi.12620] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/04/2014] [Indexed: 12/15/2022]
Abstract
Seizures are a common manifestation of acute neurologic insults in neonates and are often resistant to the standard antiepileptic drugs that are efficacious in children and adults. The paucity of evidence-based treatment guidelines, coupled with a rudimentary understanding of disease pathogenesis, has made the current treatment of neonatal seizures empiric and often ineffective, highlighting the need for novel therapies. Key developmental differences in γ-aminobutyric acid (GABA)ergic neurotransmission between the immature and mature brain, and trauma-induced alterations in the function of the cation-chloride cotransporters (CCCs) NKCC1 and KCC2, probably contribute to the poor efficacy of standard antiepileptic drugs used in the treatment of neonatal seizures. Although CCCs are attractive drug targets, bumetanide and other existing CCC inhibitors are suboptimal because of pharmacokinetic constraints and lack of target specificity. Newer approaches including isoform-specific NKCC1 inhibitors with increased central nervous system penetration, and direct and indirect strategies to enhance KCC2-mediated neuronal chloride extrusion, might allow therapeutic modulation of the GABAergic system for neonatal seizure treatment. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.
Collapse
Affiliation(s)
- Martin Puskarjov
- Department of Biosciences and Neuroscience Center, University of HelsinkiHelsinki, Finland
| | - Kristopher T Kahle
- Department of Neurosurgery, Harvard Medical School, Massachusetts General HospitalBoston, Massachusetts, U.S.A
| | - Eva Ruusuvuori
- Department of Biosciences and Neuroscience Center, University of HelsinkiHelsinki, Finland
| | - Kai Kaila
- Department of Biosciences and Neuroscience Center, University of HelsinkiHelsinki, Finland
| |
Collapse
|
35
|
Töllner K, Brandt C, Töpfer M, Brunhofer G, Erker T, Gabriel M, Feit PW, Lindfors J, Kaila K, Löscher W. A novel prodrug-based strategy to increase effects of bumetanide in epilepsy. Ann Neurol 2014; 75:550-62. [PMID: 24615913 DOI: 10.1002/ana.24124] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 10/21/2013] [Accepted: 12/21/2013] [Indexed: 11/07/2022]
Abstract
OBJECTIVE There is considerable interest in using bumetanide, a chloride importer Na-K-Cl cotransporter antagonist, for treatment of neurological diseases, such as epilepsy or ischemic and traumatic brain injury, that may involve deranged cellular chloride homeostasis. However, bumetanide is heavily bound to plasma proteins (~98%) and highly ionized at physiological pH, so that it only poorly penetrates into the brain, and chronic treatment with bumetanide is compromised by its potent diuretic effect. METHODS To overcome these problems, we designed lipophilic and uncharged prodrugs of bumetanide that should penetrate the blood-brain barrier more easily than the parent drug and are converted into bumetanide in the brain. The feasibility of this strategy was evaluated in mice and rats. RESULTS Analysis of bumetanide levels in plasma and brain showed that administration of 2 ester prodrugs of bumetanide, the pivaloyloxymethyl (BUM1) and N,N-dimethylaminoethylester (BUM5), resulted in significantly higher brain levels of bumetanide than administration of the parent drug. BUM5, but not BUM1, was less diuretic than bumetanide, so that BUM5 was further evaluated in chronic models of epilepsy in mice and rats. In the pilocarpine model in mice, BUM5, but not bumetanide, counteracted the alteration in seizure threshold during the latent period. In the kindling model in rats, BUM5 was more efficacious than bumetanide in potentiating the anticonvulsant effect of phenobarbital. INTERPRETATION Our data demonstrate that the goal of designing bumetanide prodrugs that specifically target the brain is feasible and that such drugs may resolve the problems associated with using bumetanide for treatment of neurological disorders.
Collapse
Affiliation(s)
- Kathrin Töllner
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Wang G, Huang H, He Y, Ruan L, Huang J. Bumetanide protects focal cerebral ischemia-reperfusion injury in rat. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2014; 7:1487-94. [PMID: 24817944 PMCID: PMC4014228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 02/27/2014] [Indexed: 06/03/2023]
Abstract
OBJECTIVE Bumetanide has been reported to attenuate ischemia-evoked cerebral edema. However, whether bumetanide can protect cerebral ischemia-reperfusion injury (IRI) in vivo is unclear. In the present study, we aim to determine whether intravenously injection bumetanide can attenuate cerebral IRI and if its protection effect might be related to the modification of cerebral NKCC1 and KCC2 protein expression. METHODS Focal cerebral ischemia was induced by occluding the right middle cerebral artery (MCAO) for 2-h, followed by 3-h, 24-h or 48-h of reperfusion respectively. Brain edema, neurological deficits, and infarction volume were determined by (wet weights-dry weights)/dry weights×100, 5-point neurological function score evaluation system, and TTC staining, respectively. The expression levels of NKCC1 and KCC2 were determined by immunohistochemical staining. RESULTS Reperfusion increased brain edema, neurological deficits, and infarction volume. Bumetanide decreased brain edema, attenuated the neurological defects and reduced post-ischemic cerebral infarction. Cerebral ischemia-reperfusion injury increased NKCC1 expression level and decreased KCC2 expression level. Interestingly, bumetanide down-regulated the NKCC1 protein expression level without changing the KCC2 protein expression level in rat brain cortex. CONCLUSION These results suggest that bumetanide protects focal cerebral ischemia-reperfusion injury in rat, which might through the inhibition of NKCC1.
Collapse
Affiliation(s)
- Genbao Wang
- Department of Anesthesiology, Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260, China
- Department of Anesthesiology, Affiliated Zhong San Chinese Hospital of Guang Zhou Chinese UniversityZhong San 528400, China
| | - Huansen Huang
- Department of Anesthesiology, Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260, China
| | - Yanbing He
- Department of Anesthesiology, Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260, China
| | - Lin Ruan
- Department of Anesthesiology, Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260, China
| | - Junjie Huang
- Department of Anesthesiology, Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260, China
| |
Collapse
|
37
|
Abstract
Seizures occur in approximately 1 to 5 per 1000 live births and are among the most common neurologic conditions managed by a neonatal neurocritical care service. There are several, age-specific factors that are particular to the developing brain, which influence excitability and seizure generation, response to medications, and impact of seizures on brain structure and function. Neonatal seizures are often associated with serious underlying brain injury such as hypoxia-ischemia, stroke, or hemorrhage. Conventional, prolonged, continuous video electroencephalogram is the gold standard for detecting seizures, whereas amplitude-integrated EEG is a convenient and useful bedside tool.
Collapse
Affiliation(s)
- Hannah C. Glass
- Departments of Neurology and Pediatrics University of California, San Francisco, United States of America
| |
Collapse
|
38
|
Abstract
The treatment of neonatal seizures has not changed significantly over the last 50 years despite advances in antiepileptic drug (AED) development for older children and adults. Recently new drugs have emerged some of which address age-specific challenges or mechanisms and will be discussed in this review. The loop diuretic bumetanide blocks the neuronal NKCC1 co-transporter and is thought specifically to supress seizures in the immature brain. Levetiracetam has been used in children and infants with good efficacy, an excellent safety profile, and near-ideal pharmacokinetic characteristics. Randomised controlled trials are now underway to test the efficacy of some newer AEDs for neonatal seizures. Topiramate has been shown to have neuroprotective properties in addition to its antiepileptic action and trials in babies with hypoxic-ischaemic encephalopathy are now planned. There is an urgent need to develop age-specific AEDs for preterm and term babies. These drugs must be evaluated with multicentre, collaborative trials using innovative methods and high ethical standards to overcome age-specific challenges with the ultimate aim of improving the outcome for neonates with seizures.
Collapse
|
39
|
Cleary RT, Sun H, Huynh T, Manning SM, Li Y, Rotenberg A, Talos DM, Kahle KT, Jackson M, Rakhade SN, Berry G, Jensen FE. Bumetanide enhances phenobarbital efficacy in a rat model of hypoxic neonatal seizures. PLoS One 2013; 8:e57148. [PMID: 23536761 PMCID: PMC3594228 DOI: 10.1371/journal.pone.0057148] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 01/17/2013] [Indexed: 01/30/2023] Open
Abstract
Neonatal seizures can be refractory to conventional anticonvulsants, and this may in part be due to a developmental increase in expression of the neuronal Na(+)-K(+)-2 Cl(-) cotransporter, NKCC1, and consequent paradoxical excitatory actions of GABAA receptors in the perinatal period. The most common cause of neonatal seizures is hypoxic encephalopathy, and here we show in an established model of neonatal hypoxia-induced seizures that the NKCC1 inhibitor, bumetanide, in combination with phenobarbital is significantly more effective than phenobarbital alone. A sensitive mass spectrometry assay revealed that bumetanide concentrations in serum and brain were dose-dependent, and the expression of NKCC1 protein transiently increased in cortex and hippocampus after hypoxic seizures. Importantly, the low doses of phenobarbital and bumetanide used in the study did not increase constitutive apoptosis, alone or in combination. Perforated patch clamp recordings from ex vivo hippocampal slices removed following seizures revealed that phenobarbital and bumetanide largely reversed seizure-induced changes in EGABA. Taken together, these data provide preclinical support for clinical trials of bumetanide in human neonates at risk for hypoxic encephalopathy and seizures.
Collapse
Affiliation(s)
- Ryan T. Cleary
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Hongyu Sun
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Thanhthao Huynh
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Simon M. Manning
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
- Division of Newborn Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
| | - Yijun Li
- Division of Genetics and Metabolism, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Alexander Rotenberg
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Delia M. Talos
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Kristopher T. Kahle
- Department of Neurosurgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Michele Jackson
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Sanjay N. Rakhade
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Gerard Berry
- Division of Genetics and Metabolism, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Frances E. Jensen
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
- Program in Neurobiology, Harvard Medical School, Boston, Massachusetts, United States of America
| |
Collapse
|
40
|
Berman DR, Mozurkewich E, Liu Y, Shangguan Y, Barks JD, Silverstein FS. Docosahexaenoic acid augments hypothermic neuroprotection in a neonatal rat asphyxia model. Neonatology 2013; 104:71-78. [PMID: 23817197 PMCID: PMC4721269 DOI: 10.1159/000351011] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Accepted: 03/01/2013] [Indexed: 12/18/2022]
Abstract
BACKGROUND In neonatal rats, early post-hypoxia-ischemia (HI) administration of the omega-3 fatty acid docosahexaenoic acid (DHA) improves sensorimotor function, but does not attenuate brain damage. OBJECTIVE To determine if DHA administration in addition to hypothermia, now standard care for neonatal asphyxial brain injury, attenuates post-HI damage and sensorimotor deficits. METHODS Seven-day-old (P7) rats underwent right carotid ligation followed by 90 min of 8% O2 exposure. Fifteen minutes later, pups received injections of DHA 2.5 mg/kg (complexed to 25% albumin) or equal volumes of albumin. After a 1-hour recovery, pups were cooled (3 h, 30°C). Sensorimotor and pathology outcomes were initially evaluated on P14. In subsequent experiments, sensorimotor function was evaluated on P14, P21, and P28; histopathology was assessed on P28. RESULTS At P14, left forepaw function scores (normal: 20/20) were near normal in DHA + hypothermia-treated animals (mean ± SD 19.7 ± 0.7 DHA + hypothermia vs. 12.7 ± 3.5 albumin + hypothermia, p < 0.0001) and brain damage was reduced (mean ± SD right hemisphere damage 38 ± 17% with DHA + hypothermia vs. 56 ± 15% with albumin + hypothermia, p = 0.003). Substantial improvements on three sensorimotor function measures and reduced brain damage were evident up to P28. CONCLUSION Unlike post-HI treatment with DHA alone, treatment with DHA + hypothermia produced both sustained functional improvement and reduced brain damage after neonatal HI.
Collapse
Affiliation(s)
- Deborah R Berman
- Department of Obstetrics and Gynecology; Division of Maternal Fetal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Ellen Mozurkewich
- Department of Obstetrics and Gynecology; Division of Maternal Fetal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Yiqing Liu
- Department of Pediatrics, University of Michigan, Ann Arbor, Michigan USA
| | - Yu Shangguan
- Department of Pediatrics, University of Michigan, Ann Arbor, Michigan USA
| | - John D Barks
- Department of Pediatrics, University of Michigan, Ann Arbor, Michigan USA
| | - Faye S Silverstein
- Department of Pediatrics, University of Michigan, Ann Arbor, Michigan USA.,Department of Neurology, University of Michigan, Ann Arbor, Michigan USA
| |
Collapse
|
41
|
Staley K. Neonatal encephalopathy, MRI lesions, and later epilepsy: no harm, no foul? Epilepsy Curr 2012; 12:128-30. [PMID: 22936880 PMCID: PMC3423207 DOI: 10.5698/1535-7511-12.4.128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|