1
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Schoknecht K, Maechler M, Wallach I, Dreier JP, Liotta A, Berndt N. Isoflurane lowers the cerebral metabolic rate of oxygen and prevents hypoxia during cortical spreading depolarization in vitro: An integrative experimental and modeling study. J Cereb Blood Flow Metab 2024; 44:1000-1012. [PMID: 38140913 PMCID: PMC11318408 DOI: 10.1177/0271678x231222306] [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] [Received: 05/05/2023] [Revised: 10/23/2023] [Accepted: 11/29/2023] [Indexed: 12/24/2023]
Abstract
Cortical spreading depolarization (SD) imposes a massive increase in energy demand and therefore evolves as a target for treatment following acute brain injuries. Anesthetics are empirically used to reduce energy metabolism in critical brain conditions, yet their effect on metabolism during SD remains largely unknown. We investigated oxidative metabolism during SD in brain slices from Wistar rats. Extracellular potassium ([K+]o), local field potential and partial tissue oxygen pressure (ptiO2) were measured simultaneously. The cerebral metabolic rate of oxygen (CMRO2) was calculated using a reaction-diffusion model. By that, we tested the effect of clinically relevant concentrations of isoflurane on CMRO2 during SD and modeled tissue oxygenation for different capillary pO2 values. During SD, CMRO2 increased 2.7-fold, resulting in transient hypoxia in the slice core. Isoflurane decreased CMRO2, reduced peak [K+]o, and prolonged [K+]o clearance, which indicates reduced synaptic transmission and sodium-potassium ATPase inhibition. Modeling tissue oxygenation during SD illustrates the need for increased capillary pO2 levels to prevent hypoxia. In the absence thereof, isoflurane could improve tissue oxygenation by lowering CMRO2. Therefore, isoflurane is a promising candidate for pre-clinical studies on neuronal survival in conditions involving SD.
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Affiliation(s)
- Karl Schoknecht
- Carl-Ludwig-Institute of Physiology, Medical Faculty, Leipzig University, Leipzig, Germany
| | - Mathilde Maechler
- Department of Anesthesiology and Intensive Care, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Institute of Neurophysiology, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Institute of Computer-Assisted Cardiovascular Medicine, Deutsches Herzzentrum der Charité (DHZC), Berlin, Germany
| | - Iwona Wallach
- Institute of Computer-Assisted Cardiovascular Medicine, Deutsches Herzzentrum der Charité (DHZC), Berlin, Germany
- Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Jens P Dreier
- Centre for Stroke Research Berlin, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Department of Experimental Neurology, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Department of Neurology, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Bernstein Centre for Computational Neuroscience Berlin, Berlin, Germany
- Einstein Centre for Neurosciences Berlin, Berlin, Germany
| | - Agustin Liotta
- Department of Anesthesiology and Intensive Care, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Institute of Neurophysiology, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Institute of Computer-Assisted Cardiovascular Medicine, Deutsches Herzzentrum der Charité (DHZC), Berlin, Germany
- Department of Experimental Neurology, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Institute of Health at Charité – Universitätsmedizin Berlin, Berlin
- Neuroscience Research Center, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Nikolaus Berndt
- Institute of Computer-Assisted Cardiovascular Medicine, Deutsches Herzzentrum der Charité (DHZC), Berlin, Germany
- Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), Department of Molecular Toxicology, Nuthetal, Germany
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2
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Mingazov B, Vinokurova D, Zakharov A, Khazipov R. Comparative Study of Terminal Cortical Potentials Using Iridium and Ag/AgCl Electrodes. Int J Mol Sci 2023; 24:10769. [PMID: 37445945 DOI: 10.3390/ijms241310769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 06/19/2023] [Accepted: 06/26/2023] [Indexed: 07/15/2023] Open
Abstract
Brain ischemia induces slow voltage shifts in the cerebral cortex, including waves of spreading depolarization (SD) and negative ultraslow potentials (NUPs), which are considered as brain injury markers. However, different electrode materials and locations yield variable SD and NUP features. Here, we compared terminal cortical events during isoflurane or sevoflurane euthanasia using intracortical linear iridium electrode arrays and Ag/AgCl-based electrodes in the rat somatosensory cortex. Inhalation of anesthetics caused respiratory arrest, associated with hyperpolarization and followed by SD and NUP on both Ir and Ag electrodes. Ag-NUPs were bell shaped and waned within half an hour after death. Ir-NUPs were biphasic, with the early fast phase corresponding to Ag-NUP, and the late absent on Ag electrodes, phase of a progressive depolarizing voltage shift reaching -100 mV by two hours after death. In addition, late Ir-NUPs were more ample in the deep layers than at the cortical surface. Thus, intracortical Ag and Ir electrodes reliably assess early manifestations of terminal brain injury including hyperpolarization, SD and the early phase of NUP, while the late, giant amplitude phase of NUP, which is present only on Ir electrodes, is probably related to the sensitivity of Ir electrodes to a yet unidentified factor related to brain death.
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Affiliation(s)
- Bulat Mingazov
- Laboratory of Neurobiology, Kazan Federal University, Kazan 420008, Russia
| | - Daria Vinokurova
- Laboratory of Neurobiology, Kazan Federal University, Kazan 420008, Russia
| | - Andrei Zakharov
- Laboratory of Neurobiology, Kazan Federal University, Kazan 420008, Russia
- Department of Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - Roustem Khazipov
- Laboratory of Neurobiology, Kazan Federal University, Kazan 420008, Russia
- Institut de Neurobiologie de la Méditerranée (Inserm U1249), Aix-Marseille Université, 13273 Marseille, France
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3
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Nourmohammadi A, Swift JR, de Pesters A, Guay CS, Adamo MA, Dalfino JC, Ritaccio AL, Schalk G, Brunner P. Passive functional mapping of receptive language cortex during general anesthesia using electrocorticography. Clin Neurophysiol 2023; 147:31-44. [PMID: 36634533 PMCID: PMC10267852 DOI: 10.1016/j.clinph.2022.11.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 09/30/2022] [Accepted: 11/10/2022] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To investigate the feasibility of passive functional mapping in the receptive language cortex during general anesthesia using electrocorticographic (ECoG) signals. METHODS We used subdurally placed ECoG grids to record cortical responses to speech stimuli during awake and anesthesia conditions. We identified the cortical areas with significant responses to the stimuli using the spectro-temporal consistency of the brain signal in the broadband gamma (BBG) frequency band (70-170 Hz). RESULTS We found that ECoG BBG responses during general anesthesia effectively identify cortical regions associated with receptive language function. Our analyses demonstrated that the ability to identify receptive language cortex varies across different states and depths of anesthesia. We confirmed these results by comparing them to receptive language areas identified during the awake condition. Quantification of these results demonstrated an average sensitivity and specificity of passive language mapping during general anesthesia to be 49±7.7% and 100%, respectively. CONCLUSION Our results demonstrate that mapping receptive language cortex in patients during general anesthesia is feasible. SIGNIFICANCE Our proposed protocol could greatly expand the population of patients that can benefit from passive language mapping techniques, and could eliminate the risks associated with electrocortical stimulation during an awake craniotomy.
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Affiliation(s)
- Amin Nourmohammadi
- National Center for Adaptive Neurotechnologies, Washington University School of Medicine, St. Louis, MO, USA; Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Sciences, State University of New York at Albany, Albany, NY, USA.
| | - James R Swift
- National Center for Adaptive Neurotechnologies, Washington University School of Medicine, St. Louis, MO, USA; Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Sciences, State University of New York at Albany, Albany, NY, USA.
| | - Adriana de Pesters
- National Center for Adaptive Neurotechnologies, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Sciences, State University of New York at Albany, Albany, NY, USA.
| | - Christian S Guay
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, USA.
| | - Matthew A Adamo
- Department of Neurosurgery, Albany Medical College, Albany, NY, USA.
| | - John C Dalfino
- Department of Neurosurgery, Albany Medical College, Albany, NY, USA.
| | - Anthony L Ritaccio
- Department of Neurology, Albany Medical College, Albany, NY, USA; Department of Neurology, Mayo Clinic, Jacksonville, FL, USA.
| | - Gerwin Schalk
- National Center for Adaptive Neurotechnologies, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Sciences, State University of New York at Albany, Albany, NY, USA; Chen Frontier Lab for Applied Neurotechnology, Tianqiao and Chrissy Chen Institute, Shanghai, P.R. China.
| | - Peter Brunner
- National Center for Adaptive Neurotechnologies, Washington University School of Medicine, St. Louis, MO, USA; Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Sciences, State University of New York at Albany, Albany, NY, USA; Department of Neurology, Albany Medical College, Albany, NY, USA.
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4
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Chu W, Hall J, Gurrala A, Becsey A, Raman S, Okun MS, Flores CT, Giasson BI, Vaillancourt DE, Vedam-Mai V. Evaluation of an Adoptive Cellular Therapy-Based Vaccine in a Transgenic Mouse Model of α-synucleinopathy. ACS Chem Neurosci 2022; 14:235-245. [PMID: 36571847 PMCID: PMC9853504 DOI: 10.1021/acschemneuro.2c00539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Aggregated α-synuclein, a major constituent of Lewy bodies plays a crucial role in the pathogenesis of α-synucleinopathies (SPs) such as Parkinson's disease (PD). PD is affected by the innate and adaptive arms of the immune system, and recently both active and passive immunotherapies targeted against α-synuclein are being trialed as potential novel treatment strategies. Specifically, dendritic cell-based vaccines have shown to be an effective treatment for SPs in animal models. Here, we report on the development of adoptive cellular therapy (ACT) for SP and demonstrate that adoptive transfer of pre-activated T-cells generated from immunized mice can improve survival and behavior, reduce brain microstructural impairment via magnetic resonance imaging (MRI), and decrease α-synuclein pathology burden in a peripherally induced preclinical SP model (M83) when administered prior to disease onset. This study provides preclinical evidence for ACT as a potential immunotherapy for LBD, PD and other related SPs, and future work will provide necessary understanding of the mechanisms of its action.
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Affiliation(s)
- Winston
T. Chu
- J.
Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida32611, United States,Department
of Applied Physiology and Kinesiology, University
of Florida, Gainesville, Florida32611, United States
| | - Jesse Hall
- Department
of Neurology, University of Florida, Gainesville, Florida32611, United States
| | - Anjela Gurrala
- Department
of Neurology, University of Florida, Gainesville, Florida32611, United States
| | - Alexander Becsey
- Department
of Neurology, University of Florida, Gainesville, Florida32611, United States
| | - Shreya Raman
- Department
of Neurology, University of Florida, Gainesville, Florida32611, United States
| | - Michael S. Okun
- Department
of Neurology, University of Florida, Gainesville, Florida32611, United States,Department
of Neurosurgery, University of Florida, Gainesville, Florida32611, United States,Norman
Fixel
Institute for Neurological Diseases, Gainesville, Florida32608, United States
| | - Catherine T. Flores
- Department
of Neurosurgery, University of Florida, Gainesville, Florida32611, United States
| | - Benoit I. Giasson
- Department
of Neuroscience, University of Florida, Gainesville, Florida32611, United States
| | - David E. Vaillancourt
- Department
of Applied Physiology and Kinesiology, University
of Florida, Gainesville, Florida32611, United States
| | - Vinata Vedam-Mai
- Department
of Neurology, University of Florida, Gainesville, Florida32611, United States,Norman
Fixel
Institute for Neurological Diseases, Gainesville, Florida32608, United States,. Phone: (352) 273-5557. Fax:(352) 273-5575
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5
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Fisch U, Jünger AL, Hert L, Rüegg S, Sutter R. Therapeutically induced EEG burst-suppression pattern to treat refractory status epilepticus—what is the evidence? ZEITSCHRIFT FÜR EPILEPTOLOGIE 2022. [DOI: 10.1007/s10309-022-00539-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
AbstractCurrent guidelines advocate to treat refractory status epilepticus (RSE) with continuously administered anesthetics to induce an artificial coma if first- and second-line antiseizure drugs have failed to stop seizure activity. A common surrogate for monitoring the depth of the artificial coma is the appearance of a burst-suppression pattern (BS) in the EEG. This review summarizes the current knowledge on the origin and neurophysiology of the BS phenomenon as well as the evidence from the literature for the presumed benefit of BS as therapy in adult patients with RSE.
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6
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Dobariya A, El Ahmadieh TY, Good LB, Hernandez-Reynoso AG, Jakkamsetti V, Brown R, Dunbar M, Ding K, Luna J, Kallem RR, Putnam WC, Shelton JM, Evers BM, Azami A, Geramifard N, Cogan SF, Mickey B, Pascual JM. Recording of pig neuronal activity in the comparative context of the awake human brain. Sci Rep 2022; 12:15503. [PMID: 36109613 PMCID: PMC9478131 DOI: 10.1038/s41598-022-19688-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 09/01/2022] [Indexed: 11/09/2022] Open
Abstract
Gyriform mammals display neurophysiological and neural network activity that other species exhibit only in rudimentary or dissimilar form. However, neural recordings from large mammals such as the pig can be anatomically hindered and pharmacologically suppressed by anesthetics. This curtails comparative inferences. To mitigate these limitations, we set out to modify electrocorticography, intracerebral depth and intracortical recording methods to study the anesthetized pig. In the process, we found that common forms of infused anesthesia such as pentobarbital or midazolam can be neurophysiologic suppressants acting in dose-independent fashion relative to anesthetic dose or brain concentration. Further, we corroborated that standard laboratory conditions may impose electrical interference with specific neural signals. We thus aimed to safeguard neural network integrity and recording fidelity by developing surgical, anesthesia and noise reduction methods and by working inside a newly designed Faraday cage, and evaluated this from the point of view of neurophysiological power spectral density and coherence analyses. We also utilized novel silicon carbide electrodes to minimize mechanical disruption of single-neuron activity. These methods allowed for the preservation of native neurophysiological activity for several hours. Pig electrocorticography recordings were essentially indistinguishable from awake human recordings except for the small segment of electrical activity associated with vision in conscious persons. In addition, single-neuron and paired-pulse stimulation recordings were feasible simultaneously with electrocorticography and depth electrode recordings. The spontaneous and stimulus-elicited neuronal activities thus surveyed can be recorded with a degree of precision similar to that achievable in rodent or any other animal studies and prove as informative as unperturbed human electrocorticography.
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Affiliation(s)
- Aksharkumar Dobariya
- Rare Brain Disorders Program, Department of Neurology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd. Mail Code 8813, Dallas, TX, 75390-8813, USA
| | - Tarek Y El Ahmadieh
- Department of Neurosurgery, Loma Linda University Medical Center, Loma Linda, CA, 92354, USA
| | - Levi B Good
- Rare Brain Disorders Program, Department of Neurology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd. Mail Code 8813, Dallas, TX, 75390-8813, USA
| | | | - Vikram Jakkamsetti
- Rare Brain Disorders Program, Department of Neurology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd. Mail Code 8813, Dallas, TX, 75390-8813, USA
| | - Ronnie Brown
- Department of Neurological Surgery, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Misha Dunbar
- Animal Resource Center, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Kan Ding
- Department of Neurology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Jesus Luna
- Department of Neurology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Raja Reddy Kallem
- Department of Pharmacy Practice and Clinical Pharmacology, Experimental Therapeutics Center, Texas Tech University Health Sciences Center, Dallas, TX, 75235, USA
| | - William C Putnam
- Department of Pharmacy Practice and Clinical Pharmacology, Experimental Therapeutics Center, Texas Tech University Health Sciences Center, Dallas, TX, 75235, USA
- Department of Pharmaceutical Science, School of Pharmacy, Texas Tech University Health Sciences Center, Dallas, TX, 75235, USA
| | - John M Shelton
- Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Bret M Evers
- Department of Pathology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Amirhossein Azami
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Negar Geramifard
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Stuart F Cogan
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Bruce Mickey
- Department of Neurological Surgery, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Juan M Pascual
- Rare Brain Disorders Program, Department of Neurology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd. Mail Code 8813, Dallas, TX, 75390-8813, USA.
- Department of Physiology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
- Department of Pediatrics, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
- Eugene McDermott Center for Human Growth and Development/Center for Human Genetics, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
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7
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Schmidt D, English G, Gent TC, Yanik MF, von der Behrens W. Machine learning reveals interhemispheric somatosensory coherence as indicator of anesthetic depth. Front Neuroinform 2022; 16:971231. [PMID: 36172256 PMCID: PMC9510780 DOI: 10.3389/fninf.2022.971231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 08/12/2022] [Indexed: 11/13/2022] Open
Abstract
The goal of this study was to identify features in mouse electrocorticogram recordings that indicate the depth of anesthesia as approximated by the administered anesthetic dosage. Anesthetic depth in laboratory animals must be precisely monitored and controlled. However, for the most common lab species (mice) few indicators useful for monitoring anesthetic depth have been established. We used electrocorticogram recordings in mice, coupled with peripheral stimulation, in order to identify features of brain activity modulated by isoflurane anesthesia and explored their usefulness in monitoring anesthetic depth through machine learning techniques. Using a gradient boosting regressor framework we identified interhemispheric somatosensory coherence as the most informative and reliable electrocorticogram feature for determining anesthetic depth, yielding good generalization and performance over many subjects. Knowing that interhemispheric somatosensory coherence indicates the effectively administered isoflurane concentration is an important step for establishing better anesthetic monitoring protocols and closed-loop systems for animal surgeries.
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Affiliation(s)
- Dominik Schmidt
- Institute of Neuroinformatics, Department of Information Technology and Electrical Engineering (D-ITET), ETH Zurich, University of Zurich, Zurich, Switzerland
| | - Gwendolyn English
- Institute of Neuroinformatics, Department of Information Technology and Electrical Engineering (D-ITET), ETH Zurich, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich (ZNZ), Eidgenössische Technische Hochschule Zürich (ETH), University of Zurich, Zurich, Switzerland
| | - Thomas C. Gent
- Institute of Neuroinformatics, Department of Information Technology and Electrical Engineering (D-ITET), ETH Zurich, University of Zurich, Zurich, Switzerland
- Anaesthesiology Section, Vetsuisse Faculty, Department of Clinical Diagnostics and Services, University of Zurich, Zurich, Switzerland
| | - Mehmet Fatih Yanik
- Institute of Neuroinformatics, Department of Information Technology and Electrical Engineering (D-ITET), ETH Zurich, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich (ZNZ), Eidgenössische Technische Hochschule Zürich (ETH), University of Zurich, Zurich, Switzerland
| | - Wolfger von der Behrens
- Institute of Neuroinformatics, Department of Information Technology and Electrical Engineering (D-ITET), ETH Zurich, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich (ZNZ), Eidgenössische Technische Hochschule Zürich (ETH), University of Zurich, Zurich, Switzerland
- *Correspondence: Wolfger von der Behrens
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8
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Eniwaye BP, Booth V, Hudetz AG, Zochowski M. Modeling cortical synaptic effects of anesthesia and their cholinergic reversal. PLoS Comput Biol 2022; 18:e1009743. [PMID: 35737717 PMCID: PMC9258872 DOI: 10.1371/journal.pcbi.1009743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 07/06/2022] [Accepted: 05/31/2022] [Indexed: 01/07/2023] Open
Abstract
General anesthetics work through a variety of molecular mechanisms while resulting in the common end point of sedation and loss of consciousness. Generally, the administration of common anesthetics induces reduction in synaptic excitation while promoting synaptic inhibition. Exogenous modulation of the anesthetics' synaptic effects can help determine the neuronal pathways involved in anesthesia. For example, both animal and human studies have shown that exogenously induced increases in acetylcholine in the brain can elicit wakeful-like behavior despite the continued presence of the anesthetic. However, the underlying mechanisms of anesthesia reversal at the cellular level have not been investigated. Here we apply a computational model of a network of excitatory and inhibitory neurons to simulate the network-wide effects of anesthesia, due to changes in synaptic inhibition and excitation, and their reversal by cholinergic activation through muscarinic receptors. We use a differential evolution algorithm to fit model parameters to match measures of spiking activity, neuronal connectivity, and network dynamics recorded in the visual cortex of rodents during anesthesia with desflurane in vivo. We find that facilitating muscarinic receptor effects of acetylcholine on top of anesthetic-induced synaptic changes predicts the reversal of anesthetic suppression of neurons' spiking activity, functional connectivity, as well as pairwise and population interactions. Thus, our model predicts a specific neuronal mechanism for the cholinergic reversal of anesthesia consistent with experimental behavioral observations.
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Affiliation(s)
- Bolaji P. Eniwaye
- Department of Applied Physics, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Victoria Booth
- Department of Mathematics and Department of Anesthesiology, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail: (VB); (AGH); (MZ)
| | - Anthony G. Hudetz
- Department of Applied Physics, University of Michigan, Ann Arbor, Michigan, United States of America
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail: (VB); (AGH); (MZ)
| | - Michal Zochowski
- Department of Applied Physics, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Physics and Biophysics Program, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail: (VB); (AGH); (MZ)
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9
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Ward-Flanagan R, Lo AS, Clement EA, Dickson CT. A Comparison of Brain-State Dynamics across Common Anesthetic Agents in Male Sprague-Dawley Rats. Int J Mol Sci 2022; 23:ijms23073608. [PMID: 35408973 PMCID: PMC8998244 DOI: 10.3390/ijms23073608] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/11/2022] [Accepted: 03/21/2022] [Indexed: 02/04/2023] Open
Abstract
Anesthesia is a powerful tool in neuroscientific research, especially in sleep research where it has the experimental advantage of allowing surgical interventions that are ethically problematic in natural sleep. Yet, while it is well documented that different anesthetic agents produce a variety of brain states, and consequently have differential effects on a multitude of neurophysiological factors, these outcomes vary based on dosages, the animal species used, and the pharmacological mechanisms specific to each anesthetic agent. Thus, our aim was to conduct a controlled comparison of spontaneous electrophysiological dynamics at a surgical plane of anesthesia under six common research anesthetics using a ubiquitous animal model, the Sprague-Dawley rat. From this direct comparison, we also evaluated which anesthetic agents may serve as pharmacological proxies for the electrophysiological features and dynamics of unconscious states such as sleep and coma. We found that at a surgical plane, pentobarbital, isoflurane and propofol all produced a continuous pattern of burst-suppression activity, which is a neurophysiological state characteristically observed during coma. In contrast, ketamine-xylazine produced synchronized, slow-oscillatory activity, similar to that observed during slow-wave sleep. Notably, both urethane and chloral hydrate produced the spontaneous, cyclical alternations between forebrain activation (REM-like) and deactivation (non-REM-like) that are similar to those observed during natural sleep. Thus, choice of anesthesia, in conjunction with continuous brain state monitoring, are critical considerations in order to avoid brain-state confounds when conducting neurophysiological experiments.
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Affiliation(s)
- Rachel Ward-Flanagan
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada; (R.W.-F.); (E.A.C.)
| | - Alto S. Lo
- Department of Psychology, University of Alberta, Edmonton, AB T6G 2R3, Canada;
| | - Elizabeth A. Clement
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada; (R.W.-F.); (E.A.C.)
| | - Clayton T. Dickson
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada; (R.W.-F.); (E.A.C.)
- Department of Psychology, University of Alberta, Edmonton, AB T6G 2R3, Canada;
- Department of Physiology, University of Alberta, Edmonton, AB T6G 2H7, Canada
- Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, AB T6G 2G3, Canada
- Correspondence: ; Tel.: +1-(780)-492-7860
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10
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Manzella FM, Covey DF, Jevtovic-Todorovic V, Todorovic SM. Synthetic neuroactive steroids as new sedatives and anaesthetics: Back to the future. J Neuroendocrinol 2022; 34:e13086. [PMID: 35014105 PMCID: PMC8866223 DOI: 10.1111/jne.13086] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 12/03/2021] [Accepted: 12/22/2021] [Indexed: 02/03/2023]
Abstract
Since the 1990s, there has been waning interest in researching general anaesthetics (anaesthetics). Although currently used anaesthetics are mostly safe and effective, they are not without fault. In paediatric populations and neonatal animal models, they are associated with learning impairments and neurotoxicity. In an effort to research safer anaesthetics, we have gone back to re-examine neuroactive steroids as anaesthetics. Neuroactive steroids are steroids that have direct, local effects in the central nervous system. Since the discovery of their anaesthetic effects, neuroactive steroids have been consistently used in human or veterinary clinics as preferred anaesthetic agents. Although briefly abandoned for clinical use due to unwanted vehicle side effects, there has since been renewed interest in their therapeutic value. Neuroactive steroids are safe sedative/hypnotic and anaesthetic agents across various animal species. Importantly, unlike traditional anaesthetics, they do not cause extensive neurotoxicity in the developing rodent brain. Similar to traditional anaesthetics, neuroactive steroids are modulators of synaptic and extrasynaptic γ-aminobutyric acid type A (GABAA ) receptors and their interactions at the GABAA receptor are stereo- and enantioselective. Recent work has also shown that these agents act on other ion channels, such as high- and low-voltage-activated calcium channels. Through these mechanisms of action, neuroactive steroids modulate neuronal excitability, which results in characteristic burst suppression of the electroencephalogram, and a surgical plane of anaesthesia. However, in addition to their interactions with voltage and ligand gated ions channels, neuroactive steroids interact with membrane bound metabotropic receptors and xenobiotic receptors to facilitate signaling of prosurvival, antiapoptotic pathways. These pathways play a role in their neuroprotective effects in neuronal injury and may also prevent extensive apoptosis in the developing brain during anaesthesia. The current review explores the history of neuroactive steroids as anaesthetics in humans and animal models, their diverse mechanisms of action, and their neuroprotective properties.
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Affiliation(s)
- Francesca M Manzella
- Department of Anesthesiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Douglas F Covey
- Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri, USA
- Taylor Family Institute for Innovative Psychiatric Research, Washington University in St. Louis School of Medicine, St. Louis, Missouri, USA
| | - Vesna Jevtovic-Todorovic
- Department of Anesthesiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Slobodan M Todorovic
- Department of Anesthesiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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11
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Kassab A, Hinnoutondji Toffa D, Robert M, Lesage F, Peng K, Khoa Nguyen D. Hemodynamic changes associated with common EEG patterns in critically ill patients: Pilot results from continuous EEG-fNIRS study. Neuroimage Clin 2021; 32:102880. [PMID: 34773798 PMCID: PMC8594770 DOI: 10.1016/j.nicl.2021.102880] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 11/21/2022]
Abstract
Functional near-infrared spectroscopy (fNIRS) is currently the only non-invasive method allowing for continuous long-term assessment of cerebral hemodynamic. We evaluate the feasibility of using continueous electroencephalgraphy (cEEG)-fNIRS to study the cortical hemodynamic associated with status epilepticus (SE), burst suppression (BS) and periodic discharges (PDs). Eleven adult comatose patients admitted to the neuroICU for SE were recruited, and cEEG-fNIRS monitoring was performed to measure concentration changes in oxygenated (HbO) and deoxygenated hemoglobin (HbR). Seizures were associated with a large increase HbO and a decrease in HbR whose durations were positively correlated with the seizures' length. Similar observations were made for hemodynamic changes associated with bursts, showing overall increases in HbO and decreases in HbR relative to the suppression periods. PDs were seen to induce widespread HbO increases and HbR decreases. These results suggest that normal neurovascular coupling is partially retained with the hemodynamic response to the detected EEG patterns in these patients. However, the shape and distribution of the response were highly variable. This work highlighted the feasibility of conducting long-term cEEG-fNIRS to monitor hemodynamic changes over a large cortical area in critically ill patients, opening new routes for better understanding and management of abnormal EEG patterns in neuroICU.
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Affiliation(s)
- Ali Kassab
- Department of Neurological Sciences, Université de Montréal, C.P. 6128, succ. Centre-ville, Montreal, Quebec H3C 3J7, Canada; Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Université de Montréal, 900 Saint Denis St., Montreal, Quebec H2X 0A9, Canada.
| | - Dènahin Hinnoutondji Toffa
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Université de Montréal, 900 Saint Denis St., Montreal, Quebec H2X 0A9, Canada.
| | - Manon Robert
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Université de Montréal, 900 Saint Denis St., Montreal, Quebec H2X 0A9, Canada.
| | - Frédéric Lesage
- Biomedical Engineering Institute, École Polytechnique de Montréal, 2500 Chemin de Polytechnique, Montréal, Quebec H3T 1J4, Canada; Research Center, Montreal Heart Institute, 5000 Rue Bélanger, Montreal, Quebec H1T 1C8, Canada.
| | - Ke Peng
- Department of Neurological Sciences, Université de Montréal, C.P. 6128, succ. Centre-ville, Montreal, Quebec H3C 3J7, Canada; Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Université de Montréal, 900 Saint Denis St., Montreal, Quebec H2X 0A9, Canada.
| | - Dang Khoa Nguyen
- Department of Neurological Sciences, Université de Montréal, C.P. 6128, succ. Centre-ville, Montreal, Quebec H3C 3J7, Canada; Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Université de Montréal, 900 Saint Denis St., Montreal, Quebec H2X 0A9, Canada; Division of Neurology, Centre Hospitalier de l'Université de Montréal, Université de Montréal, 1000 Saint Denis St, Montreal, Quebec (H2X OC1), Canada.
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12
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Joo P, Lee H, Wang S, Kim S, Hudetz AG. Network Model With Reduced Metabolic Rate Predicts Spatial Synchrony of Neuronal Activity. Front Comput Neurosci 2021; 15:738362. [PMID: 34690730 PMCID: PMC8529180 DOI: 10.3389/fncom.2021.738362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 09/01/2021] [Indexed: 11/25/2022] Open
Abstract
In a cerebral hypometabolic state, cortical neurons exhibit slow synchronous oscillatory activity with sparse firing. How such a synchronization spatially organizes as the cerebral metabolic rate decreases have not been systemically investigated. We developed a network model of leaky integrate-and-fire neurons with an additional dependency on ATP dynamics. Neurons were scattered in a 2D space, and their population activity patterns at varying ATP levels were simulated. The model predicted a decrease in firing activity as the ATP production rate was lowered. Under hypometabolic conditions, an oscillatory firing pattern, that is, an ON-OFF cycle arose through a failure of sustainable firing due to reduced excitatory positive feedback and rebound firing after the slow recovery of ATP concentration. The firing rate oscillation of distant neurons developed at first asynchronously that changed into burst suppression and global synchronization as ATP production further decreased. These changes resembled the experimental data obtained from anesthetized rats, as an example of a metabolically suppressed brain. Together, this study substantiates a novel biophysical mechanism of neuronal network synchronization under limited energy supply conditions.
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Affiliation(s)
- Pangyu Joo
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States.,Department of Physics, Pohang University of Science and Technology, Pohang, South Korea
| | - Heonsoo Lee
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
| | - Shiyong Wang
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
| | - Seunghwan Kim
- Department of Physics, Pohang University of Science and Technology, Pohang, South Korea
| | - Anthony G Hudetz
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
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13
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Silver NRG, Ward-Flanagan R, Dickson CT. Long-term stability of physiological signals within fluctuations of brain state under urethane anesthesia. PLoS One 2021; 16:e0258939. [PMID: 34695166 PMCID: PMC8544839 DOI: 10.1371/journal.pone.0258939] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 10/10/2021] [Indexed: 11/30/2022] Open
Abstract
Urethane, an acute laboratory anesthetic, produces distinct neurophysiological and physiological effects creating an effective model of the dynamics of natural sleep. As a model of both sleep-like neurophysiological activity and the downstream peripheral function urethane is used to model a variety of physiological and pathophysiological processes. As urethane is typically administered as a single-bolus dose, it is unclear the stability of peripheral physiological functions both within and between brain-states under urethane anesthesia. In this present study, we recorded respiration rate and heart rate concurrently with local field potentials from the neocortex and hippocampus to determine the stability of peripheral physiological functions within and between brain-states under urethane anesthesia. Our data shows electroencephalographic characteristics and breathing rate are remarkable stable over long-term recordings within minor reductions in heart rate on the same time scale. Our findings indicate that the use of urethane to model peripheral physiological functions associated with changing brain states are stable during long duration experiments.
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Affiliation(s)
| | - Rachel Ward-Flanagan
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
| | - Clayton T. Dickson
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
- Department of Psychology, University of Alberta, Edmonton, Canada
- Department of Physiology, University of Alberta, Edmonton, Canada
- Department of Anaesthesiology & Pain Medicine, University of Alberta, Edmonton, Canada
- * E-mail:
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14
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Pradier B, Wachsmuth L, Nagelmann N, Segelcke D, Kreitz S, Hess A, Pogatzki-Zahn EM, Faber C. Combined resting state-fMRI and calcium recordings show stable brain states for task-induced fMRI in mice under combined ISO/MED anesthesia. Neuroimage 2021; 245:118626. [PMID: 34637903 DOI: 10.1016/j.neuroimage.2021.118626] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 09/27/2021] [Indexed: 11/28/2022] Open
Abstract
For fMRI in animal models, the combination of low-dose anesthetic, isoflurane (ISO), and the sedative medetomidine (MED) has recently become an advocated regimen to achieve stable neuronal states and brain networks in rats that are required for reliable task-induced BOLD fMRI. However, in mice the temporal stability of neuronal states and networks in resting-state (rs)-fMRI experiments during the combined ISO/MED regimen has not been systematically investigated. Using a multimodal approach with optical calcium (Ca2+) recordings and rs-fMRI, we investigated cortical neuronal/astrocytic Ca2+activity states and brain networks at multiple time points while switching from anesthesia with 1% ISO to a combined ISO/MED regimen. We found that cortical activity states reached a steady-state 45 min following start of MED infusion as indicated by stable Ca2+ transients. Similarly, rs-networks were not statistically different between anesthesia with ISO and the combined ISO/MED regimen 45 and 100 min after start of MED. Importantly, during the transition time we identified changed rs-network signatures that likely reflect the different mode of action of the respective anesthetic; these included a dose-dependent increase in cortico-cortical functional connectivity (FC) presumably caused by reduction of ISO concentration and decreased FC in subcortical arousal nuclei due to MED infusion. Furthermore, we report detection of visual stimulation-induced BOLD fMRI during the stable ISO/MED neuronal state 45 min after induction. Based on our findings, we recommend a 45-minute waiting period after switching from ISO anesthesia to the combined ISO/MED regimen before performing rs- or task-induced fMRI experiments.
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Affiliation(s)
- Bruno Pradier
- Department of Clinical Radiology, Translational Research Imaging Center, University Hospital Münster, Münster 48149, Germany; Department of Anesthesiology Intensive Care and Pain Medicine, University Hospital Münster, Germany
| | - Lydia Wachsmuth
- Department of Clinical Radiology, Translational Research Imaging Center, University Hospital Münster, Münster 48149, Germany
| | - Nina Nagelmann
- Department of Clinical Radiology, Translational Research Imaging Center, University Hospital Münster, Münster 48149, Germany
| | - Daniel Segelcke
- Department of Anesthesiology Intensive Care and Pain Medicine, University Hospital Münster, Germany
| | - Silke Kreitz
- Institute of Experimental and Clinical Pharmacology and Toxicology, Emil Fischer Center, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Andreas Hess
- Institute of Experimental and Clinical Pharmacology and Toxicology, Emil Fischer Center, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Esther M Pogatzki-Zahn
- Department of Anesthesiology Intensive Care and Pain Medicine, University Hospital Münster, Germany
| | - Cornelius Faber
- Department of Clinical Radiology, Translational Research Imaging Center, University Hospital Münster, Münster 48149, Germany.
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15
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Gui S, Li J, Li M, Shi L, Lu J, Shen S, Li P, Mei W. Revealing the Cortical Glutamatergic Neural Activity During Burst Suppression by Simultaneous wide Field Calcium Imaging and Electroencephalography in Mice. Neuroscience 2021; 469:110-124. [PMID: 34237388 DOI: 10.1016/j.neuroscience.2021.06.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 06/26/2021] [Accepted: 06/28/2021] [Indexed: 10/20/2022]
Abstract
Burst suppression (BS) is an electroencephalogram (EEG) pattern in which signals alternates between high-amplitude slow waves (burst waves) and nearly flat low-amplitude waves (suppression waves). In this study, we used wide-field (8.32 mm × 8.32 mm) fluorescent calcium imaging to record the activity of glutamatergic neurons in the parietal and occipital cortex, in conjunction with EEG recordings under BS induced by different anesthetics (sevoflurane, isoflurane, and propofol), to investigate the spatiotemporal pattern of neural activity under BS. The calcium signal of all observed cortices was decreased during the phase of EEG suppression. However, during the phase of EEG burst, the calcium signal in areas of the medial cortex, such as the secondary motor and retrosplenial area, was excited, whereas the signal in areas of the lateral cortex, such as the hindlimb cortex, forelimb cortex, barrel field, and primary visual area, was still suppressed or only weakly excited. Correlation analysis showed a strong correlation between the EEG signal and the calcium signal in the medial cortex under BS (except for propofol induced signals). As the burst-suppression ratio (BSR) increased, the regions with strong correlation coefficients became smaller, but strong correlation coefficients were still noted in the medial cortex. Taken together, our results reveal the landscape of cortical activity underlying BS.
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Affiliation(s)
- Shen Gui
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Jiayan Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Miaowen Li
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Liang Shi
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Jinling Lu
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Shiqian Shen
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital/Harvard Medical School, 55 Fruit St, Boston, MA 02121, United States
| | - Pengcheng Li
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; HUST-Suzhou Institute for Brainsmatics, Suzhou, Jiangsu 215125, China.
| | - Wei Mei
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
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16
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Shanker A, Abel JH, Schamberg G, Brown EN. Etiology of Burst Suppression EEG Patterns. Front Psychol 2021; 12:673529. [PMID: 34177731 PMCID: PMC8222661 DOI: 10.3389/fpsyg.2021.673529] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 05/14/2021] [Indexed: 12/14/2022] Open
Abstract
Burst-suppression electroencephalography (EEG) patterns of electrical activity, characterized by intermittent high-power broad-spectrum oscillations alternating with isoelectricity, have long been observed in the human brain during general anesthesia, hypothermia, coma and early infantile encephalopathy. Recently, commonalities between conditions associated with burst-suppression patterns have led to new insights into the origin of burst-suppression EEG patterns, their effects on the brain, and their use as a therapeutic tool for protection against deleterious neural states. These insights have been further supported by advances in mechanistic modeling of burst suppression. In this Perspective, we review the origins of burst-suppression patterns and use recent insights to weigh evidence in the controversy regarding the extent to which burst-suppression patterns observed during profound anesthetic-induced brain inactivation are associated with adverse clinical outcomes. Whether the clinical intent is to avoid or maintain the brain in a state producing burst-suppression patterns, monitoring and controlling neural activity presents a technical challenge. We discuss recent advances that enable monitoring and control of burst suppression.
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Affiliation(s)
- Akshay Shanker
- Department of Anesthesiology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
- Department of Anesthesia, Critical Care, and Pain Medicine, Beth Israel Deaconess Medical Center, Boston, MA, United States
| | - John H. Abel
- Massachusetts Institute of Technology, Picower Institute for Learning and Memory, Cambridge, MA, United States
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, United States
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, United States
| | - Gabriel Schamberg
- Massachusetts Institute of Technology, Picower Institute for Learning and Memory, Cambridge, MA, United States
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, United States
| | - Emery N. Brown
- Massachusetts Institute of Technology, Picower Institute for Learning and Memory, Cambridge, MA, United States
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, United States
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17
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Effects of urethane and isoflurane on the sensory evoked response and local blood flow in the early postnatal rat somatosensory cortex. Sci Rep 2021; 11:9567. [PMID: 33953244 PMCID: PMC8099888 DOI: 10.1038/s41598-021-88461-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 03/31/2021] [Indexed: 01/01/2023] Open
Abstract
Functional studies in the central nervous system are often conducted using anesthesia. While the dose-dependent effects of anesthesia on neuronal activity have been extensively characterized in adults, little is known about the effects of anesthesia on cortical activity and cerebral blood flow in the immature central nervous system. Substitution of electrophysiological recordings with the less-invasive technique of optical intrinsic signal imaging (OIS) in vivo allowed simultaneous recordings of sensory-evoked functional response and local blood flow changes in the neonatal rat barrel cortex. Using OIS we characterize the effects of two widely used anesthetics—urethane and isoflurane. We found that both anesthetics suppressed the sensory-evoked optical intrinsic signal in a dose-dependent manner. Dependence of the cortical response suppression matched the exponential decay model. At experimental levels of anesthesia, urethane affected the evoked cortical response less than isoflurane, which is in agreement with the results of electrophysiological recordings demonstrated by other authors. Changes in oxygenation and local blood flow also showed negative correlation with both anesthetics. The high similarity in immature patterns of activity recorded in different regions of the developing cortex suggested similar principles of development regardless of the cortical region. Therefore the indicated results should be taken into account during functional explorations in the entire developing cortex. Our results also point to urethane as the anesthetic of choice in non-survival experimental recordings in the developing brain as it produces less prominent impairment of cortical neuronal activity in neonatal animals.
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Stenroos P, Pirttimäki T, Paasonen J, Paasonen E, Salo RA, Koivisto H, Natunen T, Mäkinen P, Kuulasmaa T, Hiltunen M, Tanila H, Gröhn O. Isoflurane affects brain functional connectivity in rats 1 month after exposure. Neuroimage 2021; 234:117987. [PMID: 33762218 DOI: 10.1016/j.neuroimage.2021.117987] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 02/16/2021] [Accepted: 03/16/2021] [Indexed: 10/21/2022] Open
Abstract
Isoflurane, the most commonly used preclinical anesthetic, induces brain plasticity and long-term cellular and molecular changes leading to behavioral and/or cognitive consequences. These changes are most likely associated with network-level changes in brain function. To elucidate the mechanisms underlying long-term effects of isoflurane, we investigated the influence of a single isoflurane exposure on functional connectivity, brain electrical activity, and gene expression. Male Wistar rats (n = 22) were exposed to 1.8% isoflurane for 3 h. Control rats (n = 22) spent 3 h in the same room without exposure to anesthesia. After 1 month, functional connectivity was evaluated with resting-state functional magnetic resonance imaging (fMRI; n = 6 + 6) and local field potential measurements (n = 6 + 6) in anesthetized animals. A whole genome expression analysis (n = 10+10) was also conducted with mRNA-sequencing from cortical and hippocampal tissue samples. Isoflurane treatment strengthened thalamo-cortical and hippocampal-cortical functional connectivity. Cortical low-frequency fMRI power was also significantly increased in response to the isoflurane treatment. The local field potential results indicating strengthened hippocampal-cortical alpha and beta coherence were in good agreement with the fMRI findings. Furthermore, altered expression was found in 20 cortical genes, several of which are involved in neuronal signal transmission, but no gene expression changes were noted in the hippocampus. Isoflurane induced prolonged changes in thalamo-cortical and hippocampal-cortical function and expression of genes contributing to signal transmission in the cortex. Further studies are required to investigate whether these changes are associated with the postoperative behavioral and cognitive symptoms commonly observed in patients and animals.
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Affiliation(s)
- Petteri Stenroos
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
| | - Tiina Pirttimäki
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
| | - Jaakko Paasonen
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
| | - Ekaterina Paasonen
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
| | - Raimo A Salo
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
| | - Hennariikka Koivisto
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
| | - Teemu Natunen
- Institute of Biomedicine, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
| | - Petra Mäkinen
- Institute of Biomedicine, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
| | - Teemu Kuulasmaa
- Institute of Biomedicine, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
| | - Mikko Hiltunen
- Institute of Biomedicine, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
| | - Heikki Tanila
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
| | - Olli Gröhn
- A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, FI,-70211 Kuopio, Finland
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19
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Ming Q, Liou JY, Yang F, Li J, Chu C, Zhou Q, Wu D, Xu S, Luo P, Liang J, Li D, Pryor KO, Lin W, Schwartz TH, Ma H. Isoflurane-Induced Burst Suppression Is a Thalamus-Modulated, Focal-Onset Rhythm With Persistent Local Asynchrony and Variable Propagation Patterns in Rats. Front Syst Neurosci 2021; 14:599781. [PMID: 33510621 PMCID: PMC7835516 DOI: 10.3389/fnsys.2020.599781] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 12/14/2020] [Indexed: 11/13/2022] Open
Abstract
Background: Inhalational anesthetic-induced burst suppression (BS) is classically considered a bilaterally synchronous rhythm. However, local asynchrony has been predicted in theoretical studies and reported in patients with pre-existing focal pathology. Method: We used high-speed widefield calcium imaging to study the spatiotemporal dynamics of isoflurane-induced BS in rats. Results: We found that isoflurane-induced BS is not a globally synchronous rhythm. In the neocortex, neural activity first emerged in a spatially shifting, variably localized focus. Subsequent propagation across the whole cortex was rapid, typically within <100 milliseconds, giving the superficial resemblance to global synchrony. Neural activity remained locally asynchronous during the bursts, forming complex recurrent propagating waves. Despite propagation variability, spatial sequences of burst propagation were largely preserved between the hemispheres, and neural activity was highly correlated between the homotopic areas. The critical role of the thalamus in cortical burst initiation was demonstrated by using unilateral thalamic tetrodotoxin injection. Conclusion: The classical impression that anesthetics-induced BS is a state of global brain synchrony is inaccurate. Bursts are a series of shifting local cortical events facilitated by thalamic projection that unfold as rapid, bilaterally asynchronous propagating waves.
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Affiliation(s)
- Qianwen Ming
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Jyun-You Liou
- Department of Anesthesiology, New York-Presbyterian Hospital/Weill Cornell Medicine, New York, NY, United States
| | - Fan Yang
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Jing Li
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Chaojia Chu
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Qingchen Zhou
- Department of Radiology, The First Hospital of Jilin University, Changchun, China
| | - Dan Wu
- Department of Radiology, The First Hospital of Jilin University, Changchun, China
| | - Shujia Xu
- Department of Radiology, The First Hospital of Jilin University, Changchun, China
| | - Peijuan Luo
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Jianmin Liang
- Department of Pediatrics, The First Hospital of Jilin University, Changchun, China
| | - Dan Li
- Department of Radiology, The First Hospital of Jilin University, Changchun, China
| | - Kane O Pryor
- Department of Anesthesiology, New York-Presbyterian Hospital/Weill Cornell Medicine, New York, NY, United States
| | - Weihong Lin
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Theodore H Schwartz
- Department of Neurological Surgery and Brain and Mind Research Institute, Weill Cornell Medicine of Cornell University, NewYork-Presbyterian Hospital, New York, NY, United States
| | - Hongtao Ma
- Department of Neurology, The First Hospital of Jilin University, Changchun, China.,Department of Neurological Surgery and Brain and Mind Research Institute, Weill Cornell Medicine of Cornell University, NewYork-Presbyterian Hospital, New York, NY, United States
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20
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Abstract
The anesthetic state and natural sleep share many neurobiological features and yet are two distinct states. The hallmarks of general anesthesia include hypnosis, analgesia, akinesia and anxiolysis. These are the principal parameters by which the anesthetic state differs from natural sleep. These properties are mediated by systemic administration of a combination of agents producing balanced anesthesia. The exact nature of anesthetic narcosis is dose dependent and agent specific. It exhibits a relative lack of nociceptive response and active suppression of motor and autonomic reflexes. Surgical anesthesia displays a signature electroencephalogram pattern of burst suppression that differs from rapid eye movement sleep, representing more widespread disruption of thalamocortical connectivity, impairing information integration and processing. These differences underpin successful anesthetic action. This review explores the differences between natural sleep and anesthetic-induced unconsciousness as induced by balanced anesthesia.
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Affiliation(s)
- Akshay Date
- Basildon & Thurrock University Hospital, Nethermayne, Basildon, Essex SS16 5NL, UK
| | - Khayam Bashir
- Basildon & Thurrock University Hospital, Nethermayne, Basildon, Essex SS16 5NL, UK
| | - Aaliya Uddin
- Basildon & Thurrock University Hospital, Nethermayne, Basildon, Essex SS16 5NL, UK
| | - Chandni Nigam
- Kings College Hospital, Denmark Hill, Brixton, London SE5 9RS, UK
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21
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Lobo FA, Vacas S, Rossetti AO, Robba C, Taccone FS. Does electroencephalographic burst suppression still play a role in the perioperative setting? Best Pract Res Clin Anaesthesiol 2020; 35:159-169. [PMID: 34030801 DOI: 10.1016/j.bpa.2020.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 10/21/2020] [Accepted: 10/27/2020] [Indexed: 12/18/2022]
Abstract
With the widespread use of electroencephalogram [EEG] monitoring during surgery or in the Intensive Care Unit [ICU], clinicians can sometimes face the pattern of burst suppression [BS]. The BS pattern corresponds to the continuous quasi-periodic alternation between high-voltage slow waves [the bursts] and periods of low voltage or even isoelectricity of the EEG signal [the suppression] and is extremely rare outside ICU and the operative room. BS can be secondary to increased anesthetic depth or a marker of cerebral damage, as a therapeutic endpoint [i.e., refractory status epilepticus or refractory intracranial hypertension]. In this review, we report the neurophysiological features of BS to better define its role during intraoperative and critical care settings.
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Affiliation(s)
- Francisco Almeida Lobo
- Anesthesiology Department, Centro Hospitalar de Trás-os-Montes e Alto Douro, Avenida da Noruega, Lordelo, 5000-508, Vila Real, Portugal.
| | - Susana Vacas
- Department of Anesthesiology and Perioperative Medicine, University of California Los Angeles, Reagan UCLA Medical Center, 757 Westwood Plaza #3325, Los Angeles, CA, 90095, USA.
| | - Andrea O Rossetti
- Department of Neurology, Lausanne University Hospital and University of Lausanne, CH-1011, Lausanne, Switzerland.
| | - Chiara Robba
- Azienda Ospedaliera Universitaria San Martino di Genova, Largo Rosanna Benzi,15, 16100, Genova, Italy.
| | - Fabio Silvio Taccone
- Hopital Érasme, Université Libre de Bruxelles, Department of Intensive Care Medicine, Route de Lennik, 808 1070, Brussels, Belgium.
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22
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Carton-Leclercq A, Lecas S, Chavez M, Charpier S, Mahon S. Neuronal excitability and sensory responsiveness in the thalamo-cortical network in a novel rat model of isoelectric brain state. J Physiol 2020; 599:609-629. [PMID: 33095909 DOI: 10.1113/jp280266] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 10/21/2020] [Indexed: 01/04/2023] Open
Abstract
KEY POINTS The neuronal and network properties that persist during an isoelectric coma remain largely unknown. We developed a new in vivo rat model to assess cell excitability and sensory responsiveness in the thalamo-cortical pathway during an isoflurane-induced isoelectric brain state. The isoelectric electrocorticogram reflected a complete interruption of spontaneous synaptic and firing activities in cortical and thalamic neurons. Cell excitability and sensory responses in the thalamo-cortical network persisted at a reduced level in the isoelectric condition and returned to control values after resumption of background brain activity. These findings could lead to a reassessment of the functional status of the drug-induced isoelectric state: a latent state in which individual neurons and networks retain to some extent the ability of being activated by external inputs. ABSTRACT The neuronal and network properties that persist in an isoelectric brain completely deprived of spontaneous electrical activity remain largely unexplored. Here, we developed a new in vivo rat model to examine cell excitability and sensory responsiveness in somatosensory thalamo-cortical networks during the interruption of endogenous brain activity induced by high doses of isoflurane. Electrocorticograms (ECoGs) from the barrel cortex were captured simultaneously with either intracellular recordings of subjacent cortical pyramidal neurons or extracellular records of the related thalamo-cortical neurons. Isoelectric ECoG periods reflected the disappearance of spontaneous synaptic and firing activities in cortical and thalamic neurons. This was associated with a sustained membrane hyperpolarization and a reduced intrinsic excitability in deep-layer cortical neurons, without significant changes in their membrane input resistance. Concomitantly, we found that whisker-evoked potentials in the ECoG and synaptic responses in cortical neurons were attenuated in amplitude and increased in latency. Impaired responsiveness in the barrel cortex paralleled with a lowering of the sensory-induced firing in thalamic cells. The return of endogenous brain electrical activities, after reinstatement of a control isoflurane concentration, led to the recovery of cortical neurons excitability and sensory responsiveness. These findings demonstrate the persistence of a certain level of cell excitability and sensory integration in the isoelectric state and the full recovery of cortico-thalamic functions after restoration of internal cerebral activities.
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Affiliation(s)
- Antoine Carton-Leclercq
- Institut du Cerveau, ICM, INSERM UMRS 1127, CNRS UMR 7225, Pitié-Salpêtrière Hospital, Paris, France
| | - Sarah Lecas
- Institut du Cerveau, ICM, INSERM UMRS 1127, CNRS UMR 7225, Pitié-Salpêtrière Hospital, Paris, France.,Sorbonne University, UPMC Université Paris, Paris, France
| | - Mario Chavez
- Institut du Cerveau, ICM, INSERM UMRS 1127, CNRS UMR 7225, Pitié-Salpêtrière Hospital, Paris, France
| | - Stéphane Charpier
- Institut du Cerveau, ICM, INSERM UMRS 1127, CNRS UMR 7225, Pitié-Salpêtrière Hospital, Paris, France.,Sorbonne University, UPMC Université Paris, Paris, France
| | - Séverine Mahon
- Institut du Cerveau, ICM, INSERM UMRS 1127, CNRS UMR 7225, Pitié-Salpêtrière Hospital, Paris, France
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23
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Proekt A, Kelz MB. Explaining anaesthetic hysteresis with effect-site equilibration. Br J Anaesth 2020; 126:265-278. [PMID: 33081972 DOI: 10.1016/j.bja.2020.09.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 08/16/2020] [Accepted: 09/07/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Anaesthetic induction occurs at higher plasma drug concentrations than emergence in animal studies. Some studies find evidence for such anaesthetic hysteresis in humans, whereas others do not. Traditional thinking attributes hysteresis to drug equilibration between plasma and the effect site. Indeed, a key difference between human studies showing anaesthetic hysteresis and those that do not is in how effect-site equilibration was modelled. However, the effect-site is a theoretical compartment in which drug concentration cannot be measured experimentally. Thus, it is not clear whether drug equilibration models with experimentally intractable compartments are sufficiently constrained to unequivocally establish evidence for the presence or absence of anaesthetic hysteresis. METHODS We constructed several models. One lacked hysteresis beyond effect-site equilibration. In another, neuronal dynamics contributed to hysteresis. We attempted to distinguish between these two systems using drug equilibration models. RESULTS Our modelling studies showed that one can always construct an effect-site equilibration model such that hysteresis collapses. So long as the concentration in the effect-site cannot be measured directly, the correct effect-site equilibration model and the one that erroneously collapses hysteresis are experimentally indistinguishable. We also found that hysteresis can naturally arise even in a simple network of neurones independently of drug equilibration. CONCLUSIONS Effect-site equilibration models can readily collapse hysteresis. However, this does not imply that hysteresis is solely attributable to the kinetics of drug equilibration.
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Affiliation(s)
- Alex Proekt
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Max B Kelz
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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24
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Collapse of Global Neuronal States in Caenorhabditis elegans under Isoflurane Anesthesia. Anesthesiology 2020; 133:133-144. [PMID: 32282426 DOI: 10.1097/aln.0000000000003304] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND A comprehensive understanding of how anesthetics facilitate a reversible collapse of system-wide neuronal function requires measurement of neuronal activity with single-cell resolution. Multineuron recording was performed in Caenorhabditis elegans to measure neuronal activity at varying depths of anesthesia. The authors hypothesized that anesthesia is characterized by dyssynchrony between neurons resulting in a collapse of organized system states. METHODS Using light-sheet microscopy and transgenic expression of the calcium-sensitive fluorophore GCaMP6s, a majority of neurons (n = 120) in the C. elegans head were simultaneously imaged in vivo and neuronal activity was measured. Neural activity and system-wide dynamics were compared in 10 animals, progressively dosed at 0%, 4%, and 8% isoflurane. System-wide neuronal activity was analyzed using principal component analysis. RESULTS Unanesthetized animals display distinct global neuronal states that are reflected in a high degree of correlation (R = 0.196 ± 0.070) between neurons and low-frequency, large-amplitude neuronal dynamics. At 4% isoflurane, the average correlation between neurons is significantly diminished (R = 0.026 ± 0.010; P < 0.0001 vs. unanesthetized) and neuron dynamics shift toward higher frequencies but with smaller dynamic range. At 8% isoflurane, interneuronal correlations indicate that neuronal activity remains uncoordinated (R = 0.053 ± 0.029; P < 0.0001 vs. unanesthetized) with high-frequency dynamics that are even further restricted. Principal component analysis of unanesthetized neuronal activity reveals distinct structure corresponding to known behavioral states. At 4% and 8% isoflurane this structure is lost and replaced with randomized dynamics, as quantified by the percentage of total ensemble variance captured by the first three principal components. In unanesthetized worms, this captured variance is high (88.9 ± 5.4%), reflecting a highly organized system, falling significantly at 4% and 8% isoflurane (57.9 ± 11.2%, P < 0.0001 vs. unanesthetized, and 76.0 ± 7.9%, P < 0.001 vs. unanesthetized, respectively) and corresponding to increased randomization and collapse of system-wide organization. CONCLUSIONS Anesthesia with isoflurane in C. elegans corresponds to high-frequency randomization of individual neuron activity, loss of coordination between neurons, and a collapse of system-wide functional organization.
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25
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Chu WT, DeSimone JC, Riffe CJ, Liu H, Chakrabarty P, Giasson BI, Vedam-Mai V, Vaillancourt DE. α-Synuclein Induces Progressive Changes in Brain Microstructure and Sensory-Evoked Brain Function That Precedes Locomotor Decline. J Neurosci 2020; 40:6649-6659. [PMID: 32669353 PMCID: PMC7486650 DOI: 10.1523/jneurosci.0189-20.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 04/13/2020] [Accepted: 06/08/2020] [Indexed: 02/06/2023] Open
Abstract
In vivo functional and structural brain imaging of synucleinopathies in humans have provided a rich new understanding of the affected networks across the cortex and subcortex. Despite this progress, the temporal relationship between α-synuclein (α-syn) pathology and the functional and structural changes occurring in the brain is not well understood. Here, we examine the temporal relationship between locomotor ability, brain microstructure, functional brain activity, and α-syn pathology by longitudinally conducting rotarod, diffusion magnetic resonance imaging (MRI), resting-state functional MRI (fMRI), and sensory-evoked fMRI on 20 mice injected with α-syn fibrils and 20 PBS-injected mice at three timepoints (10 males and 10 females per group). Intramuscular injection of α-syn fibrils in the hindlimb of M83+/- mice leads to progressive α-syn pathology along the spinal cord, brainstem, and midbrain by 16 weeks post-injection. Our results suggest that peripheral injection of α-syn has acute systemic effects on the central nervous system such that structural and resting-state functional activity changes occur in the brain by four weeks post-injection, well before α-syn pathology reaches the brain. At 12 weeks post-injection, a separate and distinct pattern of structural and sensory-evoked functional brain activity changes was observed that are co-localized with previously reported regions of α-syn pathology and immune activation. Microstructural changes in the pons at 12 weeks post-injection were found to predict survival time and preceded measurable locomotor deficits. This study provides preliminary evidence for diffusion and fMRI markers linked to the progression of synuclein pathology and has translational importance for understanding synucleinopathies in humans.SIGNIFICANCE STATEMENT α-Synuclein (α-syn) pathology plays a critical role in neurodegenerative diseases such as Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. The longitudinal effects of α-syn pathology on locomotion, brain microstructure, and functional brain activity are not well understood. Using high field imaging, we show preliminary evidence that peripheral injection of α-syn fibrils induces unique patterns of functional and structural changes that occur at different temporal stages of α-syn pathology progression. Our results challenge existing assumptions that α-syn pathology must precede changes in brain structure and function. Additionally, we show preliminary evidence that diffusion and functional magnetic resonance imaging (fMRI) are capable of resolving such changes and thus should be explored further as markers of disease progression.
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Affiliation(s)
- Winston T Chu
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida 32611
| | - Jesse C DeSimone
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida 32611
| | - Cara J Riffe
- Department of Neuroscience, University of Florida, Gainesville, Florida 32611
| | - Han Liu
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida 32611
| | | | - Benoit I Giasson
- Department of Neuroscience, University of Florida, Gainesville, Florida 32611
| | - Vinata Vedam-Mai
- Department of Neurology, University of Florida, Gainesville, Florida 32611
| | - David E Vaillancourt
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida 32611
- Department of Neurology, University of Florida, Gainesville, Florida 32611
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26
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Park Y, Han SH, Byun W, Kim JH, Lee HC, Kim SJ. A Real-Time Depth of Anesthesia Monitoring System Based on Deep Neural Network With Large EDO Tolerant EEG Analog Front-End. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2020; 14:825-837. [PMID: 32746339 DOI: 10.1109/tbcas.2020.2998172] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this article, we present a real-time electroencephalogram (EEG) based depth of anesthesia (DoA) monitoring system in conjunction with a deep learning framework, AnesNET. An EEG analog front-end (AFE) that can compensate ±380-mV electrode DC offset using a coarse digital DC servo loop is implemented in the proposed system. The EEG-based MAC, EEGMAC, is introduced as a novel index to accurately predict the DoA, which is designed for applying to patients anesthetized by both volatile and intravenous agents. The proposed deep learning protocol consists of four layers of convolutional neural network and two dense layers. In addition, we optimize the complexity of the deep neural network (DNN) to operate on a microcomputer such as the Raspberry Pi 3, realizing a cost-effective small-size DoA monitoring system. Fabricated in 110-nm CMOS, the prototype AFE consumes 4.33 μW per channel and has the input-referred noise of 0.29 μVrms from 0.5 to 100 Hz with the noise efficiency factor of 2.2. The proposed DNN was evaluated with pre-recorded EEG data from 374 subjects administrated by inhalational anesthetics under surgery, achieving an average squared and absolute errors of 0.048 and 0.05, respectively. The EEGMAC with subjects anesthetized by an intravenous agent also showed a good agreement with the bispectral index value, confirming the proposed DoA index is applicable to both anesthetics. The implemented monitoring system with the Raspberry Pi 3 estimates the EEGMAC within 20 ms, which is about thousand-fold faster than the BIS estimation in literature.
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27
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Theilmann W, Rosenholm M, Hampel P, Löscher W, Rantamäki T. Lack of antidepressant effects of burst-suppressing isoflurane anesthesia in adult male Wistar outbred rats subjected to chronic mild stress. PLoS One 2020; 15:e0235046. [PMID: 32579566 PMCID: PMC7313995 DOI: 10.1371/journal.pone.0235046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 05/04/2020] [Indexed: 11/30/2022] Open
Abstract
Post-ictal emergence of slow wave EEG (electroencephalogram) activity and burst-suppression has been associated with the therapeutic effects of the electroconvulsive therapy (ECT), indicating that mere “cerebral silence” may elicit antidepressant actions. Indeed, brief exposures to burst-suppressing anesthesia has been reported to elicit antidepressant effects in a subset of patients, and produce behavioral and molecular alterations, such as increased expression of brain-derived neurotrophic factor (BDNF), connected with antidepressant responses in rodents. Here, we have further tested the cerebral silence hypothesis by determining whether repeated exposures to isoflurane anesthesia reduce depressive-like symptoms or influence BDNF expression in male Wistar outbred rats (Crl:WI(Han)) subjected to chronic mild stress (CMS), a model which is responsive to repeated electroconvulsive shocks (ECS, a model of ECT). Stress-susceptible, stress-resilient, and unstressed rats were exposed to 5 doses of isoflurane over a 15-day time period, with administrations occurring every third day. Isoflurane dosing is known to reliably produce rapid EEG burst-suppression (4% induction, 2% maintenance; 15 min). Antidepressant and anxiolytic effects of isoflurane were assessed after the first, third, and fifth drug exposure by measuring sucrose consumption, as well as performance on the open field and the elevated plus maze tasks. Tissue samples from the medial prefrontal cortex and hippocampus were collected, and levels of BDNF (brain-derived neurotrophic factor) protein were assessed. We find that isoflurane anesthesia had no impact on the behavior of stress-resilient or anhedonic rats in selected tests; findings which were consistent—perhaps inherently related—with unchanged levels of BDNF.
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Affiliation(s)
- Wiebke Theilmann
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Marko Rosenholm
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, Laboratory of Neurotherapeutics, Drug Research Program, University of Helsinki, Helsinki, Finland
- SleepWell Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Philip Hampel
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Tomi Rantamäki
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, Laboratory of Neurotherapeutics, Drug Research Program, University of Helsinki, Helsinki, Finland
- SleepWell Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
- * E-mail:
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28
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Liou JY, Baird-Daniel E, Zhao M, Daniel A, Schevon CA, Ma H, Schwartz TH. Burst suppression uncovers rapid widespread alterations in network excitability caused by an acute seizure focus. Brain 2020; 142:3045-3058. [PMID: 31436790 DOI: 10.1093/brain/awz246] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 06/19/2019] [Accepted: 06/22/2019] [Indexed: 01/25/2023] Open
Abstract
Burst suppression is an electroencephalogram pattern of globally symmetric alternating high amplitude activity and isoelectricity that can be induced by general anaesthetics. There is scattered evidence that burst suppression may become spatially non-uniform in the setting of underlying pathology. Here, we induced burst suppression with isoflurane in rodents and then created a neocortical acute seizure focus with injection of 4-aminopyridine (4-AP) in somatosensory cortex. Burst suppression events were recorded before and after creation of the focus using bihemispheric wide-field calcium imaging and multielectrode arrays. We find that the seizure focus elicits a rapid alteration in triggering, initiation, and propagation of burst suppression events. Compared with the non-seizing brain, bursts are triggered from the thalamus, initiate in regions uniquely outside the epileptic focus, elicit marked increases of multiunit activity and propagate towards the seizure focus. These findings support the rapid, widespread impact of focal epilepsy on the extended brain network.
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Affiliation(s)
- Jyun-You Liou
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY, USA.,Department of Anesthesiology, Weill Cornell Medicine, New York, New York, NY, USA
| | - Eliza Baird-Daniel
- Department of Neurological Surgery, Feil Family Brain and Mind Research Institute, Sackler Brain and Spine Institute, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA
| | - Mingrui Zhao
- Department of Neurological Surgery, Feil Family Brain and Mind Research Institute, Sackler Brain and Spine Institute, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA
| | - Andy Daniel
- Department of Neurological Surgery, Feil Family Brain and Mind Research Institute, Sackler Brain and Spine Institute, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA
| | - Catherine A Schevon
- Department of Neurology, Columbia University Medical Center, New York, New York, USA
| | - Hongtao Ma
- Department of Neurological Surgery, Feil Family Brain and Mind Research Institute, Sackler Brain and Spine Institute, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA
| | - Theodore H Schwartz
- Department of Neurological Surgery, Feil Family Brain and Mind Research Institute, Sackler Brain and Spine Institute, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA
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Reimann HM, Niendorf T. The (Un)Conscious Mouse as a Model for Human Brain Functions: Key Principles of Anesthesia and Their Impact on Translational Neuroimaging. Front Syst Neurosci 2020; 14:8. [PMID: 32508601 PMCID: PMC7248373 DOI: 10.3389/fnsys.2020.00008] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 01/27/2020] [Indexed: 12/11/2022] Open
Abstract
In recent years, technical and procedural advances have brought functional magnetic resonance imaging (fMRI) to the field of murine neuroscience. Due to its unique capacity to measure functional activity non-invasively, across the entire brain, fMRI allows for the direct comparison of large-scale murine and human brain functions. This opens an avenue for bidirectional translational strategies to address fundamental questions ranging from neurological disorders to the nature of consciousness. The key challenges of murine fMRI are: (1) to generate and maintain functional brain states that approximate those of calm and relaxed human volunteers, while (2) preserving neurovascular coupling and physiological baseline conditions. Low-dose anesthetic protocols are commonly applied in murine functional brain studies to prevent stress and facilitate a calm and relaxed condition among animals. Yet, current mono-anesthesia has been shown to impair neural transmission and hemodynamic integrity. By linking the current state of murine electrophysiology, Ca2+ imaging and fMRI of anesthetic effects to findings from human studies, this systematic review proposes general principles to design, apply and monitor anesthetic protocols in a more sophisticated way. The further development of balanced multimodal anesthesia, combining two or more drugs with complementary modes of action helps to shape and maintain specific brain states and relevant aspects of murine physiology. Functional connectivity and its dynamic repertoire as assessed by fMRI can be used to make inferences about cortical states and provide additional information about whole-brain functional dynamics. Based on this, a simple and comprehensive functional neurosignature pattern can be determined for use in defining brain states and anesthetic depth in rest and in response to stimuli. Such a signature can be evaluated and shared between labs to indicate the brain state of a mouse during experiments, an important step toward translating findings across species.
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Affiliation(s)
- Henning M. Reimann
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max-Delbrück Center for Molecular Medicine, Helmholtz Association of German Research Centers (HZ), Berlin, Germany
| | - Thoralf Niendorf
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max-Delbrück Center for Molecular Medicine, Helmholtz Association of German Research Centers (HZ), Berlin, Germany
- Experimental and Clinical Research Center, A Joint Cooperation Between the Charité Medical Faculty and the Max-Delbrück Center for Molecular Medicine, Berlin, Germany
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30
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Gwilt M, Bauer M, Bast T. Frequency- and state-dependent effects of hippocampal neural disinhibition on hippocampal local field potential oscillations in anesthetized rats. Hippocampus 2020; 30:1021-1043. [PMID: 32396678 DOI: 10.1002/hipo.23212] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 03/09/2020] [Accepted: 04/09/2020] [Indexed: 11/11/2022]
Abstract
Reduced inhibitory GABA function, so-called neural disinhibition, has been implicated in cognitive disorders, including schizophrenia and age-related cognitive decline. We previously showed in rats that hippocampal disinhibition by local microinfusion of the GABA-A receptor antagonist picrotoxin disrupted memory and attention and enhanced hippocampal multi-unit burst firing recorded around the infusion site under isoflurane anesthesia. Here, we analyzed the hippocampal local field potential (LFP) recorded alongside the multi-unit data. We predicted frequency-specific LFP changes, based on previous studies implicating GABA in hippocampal oscillations, with the weight of evidence suggesting that disinhibition would facilitate theta and disrupt gamma oscillations. Using a new semi-automated method based on the kurtosis of the LFP peak-amplitude distribution as well as on amplitude envelope thresholding, we separated three distinct hippocampal LFP states under isoflurane anesthesia: "burst" and "suppression" states-high-amplitude LFP spike bursts and the interspersed low-amplitudeperiods-and a medium-amplitude "continuous" state. The burst state showed greater overall power than suppression and continuous states and higher relative delta/theta power, but lower relative beta/gamma power. The burst state also showed reduced functional connectivity across the hippocampal recording area, especially around theta and beta frequencies. Overall neuronal firing was higher in the burst than the other two states, whereas the proportion of burst firing was higher in burst and continuous states than the suppression state. Disinhibition caused state- and frequency-dependent LFP changes, tending to increase power at lower frequencies (<20 Hz), but to decrease power and connectivity at higher frequencies (>20 Hz) in burst and suppression states. The disinhibition-induced enhancement of multi-unit bursting was also state-dependent, tending to be more pronounced in burst and suppression states than the continuous state. Overall, we characterized three distinct hippocampal LFP states in isoflurane-anesthetized rats. Disinhibition changed hippocampal LFP oscillations in a state- and frequency-dependent way. Moreover, the disinhibition-induced enhancement of multi-unit bursting was also LFP state-dependent.
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Affiliation(s)
- Miriam Gwilt
- School of Psychology and Neuroscience@Nottingham, University of Nottingham, Nottingham, UK
| | - Markus Bauer
- School of Psychology and Neuroscience@Nottingham, University of Nottingham, Nottingham, UK
| | - Tobias Bast
- School of Psychology and Neuroscience@Nottingham, University of Nottingham, Nottingham, UK
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31
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Rantamäki T, Kohtala S. Encoding, Consolidation, and Renormalization in Depression: Synaptic Homeostasis, Plasticity, and Sleep Integrate Rapid Antidepressant Effects. Pharmacol Rev 2020; 72:439-465. [DOI: 10.1124/pr.119.018697] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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Maternal Fluoxetine Exposure Alters Cortical Hemodynamic and Calcium Response of Offspring to Somatosensory Stimuli. eNeuro 2019; 6:ENEURO.0238-19.2019. [PMID: 31843753 PMCID: PMC6978917 DOI: 10.1523/eneuro.0238-19.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 10/04/2019] [Accepted: 11/17/2019] [Indexed: 11/21/2022] Open
Abstract
Epidemiological studies have found an increased incidence of neurodevelopmental disorders in populations prenatally exposed to selective serotonin reuptake inhibitors (SSRIs). Optical imaging provides a minimally invasive way to determine if perinatal SSRI exposure has long-term effects on cortical function. Herein we probed the functional neuroimaging effects of perinatal SSRI exposure in a fluoxetine (FLX)-exposed mouse model. Epidemiological studies have found an increased incidence of neurodevelopmental disorders in populations prenatally exposed to selective serotonin reuptake inhibitors (SSRIs). Optical imaging provides a minimally invasive way to determine if perinatal SSRI exposure has long-term effects on cortical function. Herein we probed the functional neuroimaging effects of perinatal SSRI exposure in a fluoxetine (FLX)-exposed mouse model. While resting-state homotopic contralateral functional connectivity was unperturbed, the evoked cortical response to forepaw stimulation was altered in FLX mice. The stimulated cortex showed decreased activity for FLX versus controls, by both hemodynamic responses [oxyhemoglobin (HbO2)] and neuronal calcium responses (Thy1-GCaMP6f fluorescence). Significant alterations in both cortical HbO2 and calcium response amplitude were seen in the cortex ipsilateral to the stimulated paw in FLX as compared to controls. The cortical regions of largest difference in activation between FLX and controls also were consistent between HbO2 and calcium contrasts at the end of stimulation. Taken together, these results suggest a global loss of response signal amplitude in FLX versus controls. These findings indicate that perinatal SSRI exposure has long-term consequences on somatosensory cortical responses.
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Yin L, Li L, Deng J, Wang D, Guo Y, Zhang X, Li H, Zhao S, Zhong H, Dong H. Optogenetic/Chemogenetic Activation of GABAergic Neurons in the Ventral Tegmental Area Facilitates General Anesthesia via Projections to the Lateral Hypothalamus in Mice. Front Neural Circuits 2019; 13:73. [PMID: 31798420 PMCID: PMC6878851 DOI: 10.3389/fncir.2019.00073] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 10/31/2019] [Indexed: 12/26/2022] Open
Abstract
The ventral tegmental area (VTA) reportedly regulates sleep and wakefulness through communication with the lateral hypothalamus (LH). It has also been suggested that adequate anesthesia produced by administration of chloral hydrate, ketamine, or halothane significantly reduces the GABAergic neuronal firing rate within the VTA. However, the exact effects on GABAergic neurons in the VTA and the mechanisms through which these neurons modulate anesthesia through associated neural circuits is still unclear. Here, we used optogenetic and chemogenetic methods to specifically activate or inhibit GABAergic neuronal perikarya in the VTA or their projections to the LH in Vgat-Cre mice. Electroencephalogram (EEG) spectral analyses and burst suppression ratio (BSR) calculations were conducted following administration of 0.8 or 1.0% isoflurane, respectively; and loss of righting reflex (LORR), recovery of righting reflex (RORR), and anesthesia sensitivity were assessed under 1.4% isoflurane anesthesia. The results showed that activation of GABAergic neurons in the VTA increased delta wave power from 40.0 to 46.4% (P = 0.006) and decreased gamma wave power from 15.2 to 11.5% (P = 0.017) during anesthesia maintenance. BSR was increased from 51.8 to 68.3% (P = 0.017). Induction time (LORR) was reduced from 333 to 290 s (P = 0.019), whereas arousal time (RORR) was prolonged from 498 to 661 s (P = 0.007). Conversely, inhibition of VTA GABAergic neurons led to opposite effects. In contrast, optical activation of VTA-LH GABAergic projection neurons increased power of slow delta waves from 44.2 to 48.8% (P = 0.014) and decreased that of gamma oscillations from 10.2 to 8.0%. BSR was increased from 39.9 to 60.2% (P = 0.0002). LORR was reduced from 330 to 232 s (P = 0.002), and RORR increased from 396 to 565 s (P = 0.007). Optical inhibition of the projection neurons caused opposite effects in terms of both the EEG spectrum and the BSR, except that inhibition of this projection did not accelerate arousal time. These results indicate that VTA GABAergic neurons could facilitate the anesthetic effects of isoflurane during induction and maintenance while postponing anesthetic recovery, at least partially, through modulation of their projections to the LH.
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Affiliation(s)
- Lu Yin
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Long Li
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Jiao Deng
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Dan Wang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - YongXin Guo
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - XinXin Zhang
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - HuiMing Li
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - ShiYi Zhao
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - HaiXing Zhong
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - HaiLong Dong
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
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Burnsed J, Skwarzyńska D, Wagley PK, Isbell L, Kapur J. Neuronal Circuit Activity during Neonatal Hypoxic-Ischemic Seizures in Mice. Ann Neurol 2019; 86:927-938. [PMID: 31509619 DOI: 10.1002/ana.25601] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 09/09/2019] [Accepted: 09/09/2019] [Indexed: 12/19/2022]
Abstract
OBJECTIVE To identify circuits active during neonatal hypoxic-ischemic (HI) seizures and seizure propagation using electroencephalography (EEG), behavior, and whole-brain neuronal activity mapping. METHODS Mice were exposed to HI on postnatal day 10 using unilateral carotid ligation and global hypoxia. EEG and video were recorded for the duration of the experiment. Using immediate early gene reporter mice, active cells expressing cfos were permanently tagged with reporter protein tdTomato during a 90-minute window. After 1 week, allowing maximal expression of the reporter protein, whole brains were processed, lipid cleared, and imaged with confocal microscopy. Whole-brain reconstruction and analysis of active neurons (colocalized tdTomato/NeuN) were performed. RESULTS HI resulted in seizure behaviors that were bilateral or unilateral tonic-clonic and nonconvulsive in this model. Mice exhibited characteristic EEG background patterns such as burst suppression and suppression. Neuronal activity mapping revealed bilateral motor cortex and unilateral, ischemic somatosensory cortex, lateral thalamus, and hippocampal circuit activation. Immunohistochemical analysis revealed regional differences in myelination, which coincide with these activity patterns. Astrocytes and blood vessel endothelial cells also expressed cfos during HI. INTERPRETATION Using a combination of EEG, seizure semiology analysis, and whole-brain neuronal activity mapping, we suggest that this rodent model of neonatal HI results in EEG patterns similar to those observed in human neonates. Activation patterns revealed in this study help explain complex seizure behaviors and EEG patterns observed in neonatal HI injury. This pattern may be, in part, secondary to regional differences in development in the neonatal brain. ANN NEUROL 2019;86:927-938.
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Affiliation(s)
- Jennifer Burnsed
- Department of Pediatrics, University of Virginia, Charlottesville, VA.,Department of Neurology, University of Virginia, Charlottesville, VA
| | - Daria Skwarzyńska
- Department of Pediatrics, University of Virginia, Charlottesville, VA
| | - Pravin K Wagley
- Department of Pediatrics, University of Virginia, Charlottesville, VA
| | - Laura Isbell
- College of Arts and Sciences, University of Virginia, Charlottesville, VA
| | - Jaideep Kapur
- Department of Neurology, University of Virginia, Charlottesville, VA.,University of Virginia Brain Institute, University of Virginia, Charlottesville, VA.,Department of Neuroscience, University of Virginia, Charlottesville, VA
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Jiang X, Yan Y, Wang K, Wei J, Su W, Jia J. Brain state-dependent alterations of corticostriatal synchronized oscillations in awake and anesthetized parkinsonian rats. Brain Res 2019; 1717:214-227. [DOI: 10.1016/j.brainres.2019.04.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Revised: 04/16/2019] [Accepted: 04/17/2019] [Indexed: 12/29/2022]
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van Alst TM, Wachsmuth L, Datunashvili M, Albers F, Just N, Budde T, Faber C. Anesthesia differentially modulates neuronal and vascular contributions to the BOLD signal. Neuroimage 2019; 195:89-103. [DOI: 10.1016/j.neuroimage.2019.03.057] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 03/06/2019] [Accepted: 03/25/2019] [Indexed: 11/27/2022] Open
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Shortal BP, Hickman LB, Mak-McCully RA, Wang W, Brennan C, Ung H, Litt B, Tarnal V, Janke E, Picton P, Blain-Moraes S, Maybrier HR, Muench MR, Lin N, Avidan MS, Mashour GA, McKinstry-Wu AR, Kelz MB, Palanca BJ, Proekt A. Duration of EEG suppression does not predict recovery time or degree of cognitive impairment after general anaesthesia in human volunteers. Br J Anaesth 2019; 123:206-218. [PMID: 31202561 DOI: 10.1016/j.bja.2019.03.046] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 02/14/2019] [Accepted: 03/08/2019] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Burst suppression occurs in the EEG during coma and under general anaesthesia. It has been assumed that burst suppression represents a deeper state of anaesthesia from which it is more difficult to recover. This has not been directly demonstrated, however. Here, we test this hypothesis directly by assessing relationships between EEG suppression in human volunteers and recovery of consciousness. METHODS We recorded the EEG of 27 healthy humans (nine women/18 men) anaesthetised with isoflurane 1.3 minimum alveolar concentration (MAC) for 3 h. Periods of EEG suppression and non-suppression were separated using principal component analysis of the spectrogram. After emergence, participants completed the digit symbol substitution test and the psychomotor vigilance test. RESULTS Volunteers demonstrated marked variability in multiple features of the suppressed EEG. In order to test the hypothesis that, for an individual subject, inclusion of features of suppression would improve accuracy of a model built to predict time of emergence, two types of models were constructed: one with a suppression-related feature included and one without. Contrary to our hypothesis, Akaike information criterion demonstrated that the addition of a suppression-related feature did not improve the ability of the model to predict time to emergence. Furthermore, the amounts of EEG suppression and decrements in cognitive task performance relative to pre-anaesthesia baseline were not significantly correlated. CONCLUSIONS These findings suggest that, in contrast to current assumptions, EEG suppression in and of itself is not an important determinant of recovery time or the degree of cognitive impairment upon emergence from anaesthesia in healthy adults.
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Affiliation(s)
- B P Shortal
- Neuroscience Graduate Group, University of Pennsylvania, Philadelphia, PA, USA
| | - L B Hickman
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA
| | - R A Mak-McCully
- Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - W Wang
- Department of Mathematics, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - C Brennan
- Neuroscience Graduate Group, University of Pennsylvania, Philadelphia, PA, USA
| | - H Ung
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - B Litt
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA; Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - V Tarnal
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, USA
| | - E Janke
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, USA
| | - P Picton
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, USA
| | - S Blain-Moraes
- School of Physical and Occupational Therapy, McGill University, Montreal, QC, Canada
| | - H R Maybrier
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA
| | - M R Muench
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA
| | - N Lin
- Department of Mathematics, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - M S Avidan
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA
| | - G A Mashour
- Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, MI, USA
| | - A R McKinstry-Wu
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - M B Kelz
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - B J Palanca
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA
| | - A Proekt
- School of Physical and Occupational Therapy, McGill University, Montreal, QC, Canada; Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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- Department of Anesthesiology and Critical Care, University of Pennsylvania, USA; Department of Anesthesiology, Washington University, St. Louis, MO, USA; Center for Consciousness Science, Department of Anesthesiology, Ann Arbor, MI, USA
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Aggarwal A, Brennan C, Shortal B, Contreras D, Kelz MB, Proekt A. Coherence of Visual-Evoked Gamma Oscillations Is Disrupted by Propofol but Preserved Under Equipotent Doses of Isoflurane. Front Syst Neurosci 2019; 13:19. [PMID: 31139058 PMCID: PMC6519322 DOI: 10.3389/fnsys.2019.00019] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 04/18/2019] [Indexed: 12/15/2022] Open
Abstract
Previous research demonstrates that the underlying state of the brain influences how sensory stimuli are processed. Canonically, the state of the brain has been defined by quantifying the spectral characteristics of spontaneous fluctuations in local field potentials (LFP). Here, we utilized isoflurane and propofol anesthesia to parametrically alter the spectral state of the murine brain. With either drug, we produce slow wave activity, with low anesthetic doses, or burst suppression, with higher doses. We find that while spontaneous LFP oscillations were similar, the average visual-evoked potential (VEP) was always smaller in amplitude and shorter in duration under propofol than under comparable doses of isoflurane. This diminished average VEP results from increased trial-to-trial variability in VEPs under propofol. One feature of single trial VEPs that was consistent in all animals was visual-evoked gamma band oscillation (20-60 Hz). This gamma band oscillation was coherent between trials in the early phase (<250 ms) of the visual evoked potential under isoflurane. Inter trial phase coherence (ITPC) of gamma oscillations was dramatically attenuated in the same propofol anesthetized mice despite similar spontaneous oscillations in the LFP. This suggests that while both anesthetics lead to loss of consciousness (LOC), elicit slow oscillations and burst suppression, only the isoflurane permits phase resetting of gamma oscillations by visual stimuli. These results demonstrate that accurate characterization of a brain state must include both spontaneous as well as stimulus-induced perturbations of brain activity.
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Affiliation(s)
- Adeeti Aggarwal
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Connor Brennan
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Brenna Shortal
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Diego Contreras
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Max B Kelz
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Alex Proekt
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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Zhang Z, Cai DC, Wang Z, Zeljic K, Wang Z, Wang Y. Isoflurane-Induced Burst Suppression Increases Intrinsic Functional Connectivity of the Monkey Brain. Front Neurosci 2019; 13:296. [PMID: 31031580 PMCID: PMC6470287 DOI: 10.3389/fnins.2019.00296] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 03/13/2019] [Indexed: 12/22/2022] Open
Abstract
Animal functional magnetic resonance imaging (fMRI) has provided key insights into the physiological mechanisms underlying healthy and diseased brain states. In non-human primates, resting-state fMRI studies are commonly conducted under isoflurane anesthesia, where anesthetic concentration is used to roughly infer anesthesia depth. However, within the recommended isoflurane concentration range (1.00–1.50%), the brain state can switch from moderate anesthesia characterized by stable slow wave (SW) electroencephalogram (EEG) signals to deep anesthesia characterized by burst suppression (BS), which is electrophysiologically distinct from the resting state. To confirm the occurrence rate of BS activity in common setting of animal fMRI study, we conducted simultaneous resting-state EEG and fMRI experiments on 16 monkeys anesthetized using 0.80–1.30% isoflurane, and detected BS activity in two of them. Datasets either featured with BS or SW activity from these two monkeys were analyzed to investigate the intrinsic functional connectivity (FC) patterns during BS. In datasets with BS activity, we observed robust coupling between the BS pattern (the binary alternation between burst and suppression activity in EEG signal) and filtered BOLD signals in most brain areas, which was associated with a non-specific enhancement in whole brain connectivity. After eliminating the BS coupling effect by regressing out the BS pattern, we detected an overall increase in FC with a few decreased connectivity compared to datasets with SW activity. These affected connections were preferentially distributed within orbitofrontal cortex, between orbitofrontal and prefrontal/cingulate/occipital cortex, and between temporal and parietal cortex. Persistence of the default mode network and recovery of thalamocortical connections were also detected under deep anesthesia with BS activity. Taken together, the observed spatially specific alterations in BS activity induced by isoflurane not only highlight the necessity of EEG monitoring and careful data preprocessing in fMRI studies on anesthetized animals, but also advance our understanding of the underlying multi-phased mechanisms of anesthesia.
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Affiliation(s)
- Zhao Zhang
- Department of Anesthesiology, Huashan Hospital, Fudan University, Shanghai, China
| | - Dan-Chao Cai
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Zhiwei Wang
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Kristina Zeljic
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Zheng Wang
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Key Laboratory of Primate Neurobiology, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China.,Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Yingwei Wang
- Department of Anesthesiology, Huashan Hospital, Fudan University, Shanghai, China
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Williams AJ, Sun QQ. Cortical Layer and Spectrotemporal Architecture of Epileptiform Activity in vivo in a Mouse Model of Focal Cortical Malformation. Front Neural Circuits 2019; 13:2. [PMID: 30723398 PMCID: PMC6349724 DOI: 10.3389/fncir.2019.00002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Accepted: 01/07/2019] [Indexed: 12/15/2022] Open
Abstract
Our objective is to examine the layer and spectrotemporal architecture and laminar distribution of high-frequency oscillations (HFOs) in a neonatal freeze lesion model of focal cortical dysplasia (FCD) associated with a high prevalence of spontaneous spike-wave discharges (SWDs). Electrophysiological recording of local field potentials (LFPs) in control and freeze lesion animals were obtained with linear micro-electrode arrays to detect presence of HFOs as compared to changes in spectral power, signal coherence, and single-unit distributions during "hyper-excitable" epochs of anesthesia-induced burst-suppression (B-S). Result were compared to HFOs observed during spontaneous SWDs in animals during sleep. Micro-electrode array recordings from the malformed cortex indicated significant increases in the presence of HFOs above 100 Hz and associated increases in spectral power and altered LFP coherence of recorded signals across cortical lamina of freeze-lesioned animals with spontaneous bursts of high-frequency activity, confined predominately to granular and supragranular layers. Spike sorting of well-isolated single-units recorded from freeze-lesioned cortex indicated an increase in putative excitatory cell activity in the outer cortical layers that showed only a weak association with HFOs while deeper inhibitory units were strongly phase-locked to high-frequency ripple (HFR) oscillations (300-800 Hz). Both SWDs and B-S show increases in HFR activity that were phase-locked to the high-frequency spike pattern occurring at the trough of low frequency oscillations. The spontaneous cyclic spiking of cortical inhibitory cells appears to be the driving substrate behind the HFO patterns associated with SWDs and a hyperexcitable supragranular layer near the malformed cortex may play a key role in epileptogenesis in our model. These data, derived from a mouse model with a distinct focal cortical malformation, support recent clinical data that HFOs, particularly fast ripples, is a biomarker to help define the cortical seizure zone, and provide limited insights toward understanding cellular level changes underlying the HFOs.
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Affiliation(s)
- Anthony J Williams
- Department of Zoology & Physiology, University of Wyoming, Laramie, WY, United States
| | - Qian-Quan Sun
- Department of Zoology & Physiology, University of Wyoming, Laramie, WY, United States
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Hentschke H, Raz A, Krause BM, Murphy CA, Banks MI. Disruption of cortical network activity by the general anaesthetic isoflurane. Br J Anaesth 2019; 119:685-696. [PMID: 29121295 DOI: 10.1093/bja/aex199] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/02/2017] [Indexed: 02/03/2023] Open
Abstract
Background Actions of general anaesthetics on activity in the cortico-thalamic network likely contribute to loss of consciousness and disconnection from the environment. Previously, we showed that the general anaesthetic isoflurane preferentially suppresses cortically evoked synaptic responses compared with thalamically evoked synaptic responses, but how this differential sensitivity translates into changes in network activity is unclear. Methods We investigated isoflurane disruption of spontaneous and stimulus-induced cortical network activity using multichannel recordings in murine auditory thalamo-cortical brain slices. Results Under control conditions, afferent stimulation elicited short latency, presumably monosynaptically driven, spiking responses, as well as long latency network bursts that propagated horizontally through the cortex. Isoflurane (0.05-0.6 mM) suppressed spiking activity overall, but had a far greater effect on network bursts than on early spiking responses. At isoflurane concentrations >0.3 mM, network bursts were almost entirely blocked, even with increased stimulation intensity and in response to paired (thalamo-cortical + cortical layer 1) stimulation, while early spiking responses were <50% blocked. Isoflurane increased the threshold for eliciting bursts, decreased their propagation speed and prevented layer 1 afferents from facilitating burst induction by thalamo-cortical afferents. Conclusions Disruption of horizontal activity spread and of layer 1 facilitation of thalamo-cortical responses likely contribute to the mechanism by which suppression of cortical feedback connections disrupts sensory awareness under anaesthesia.
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Affiliation(s)
- H Hentschke
- Department of Anesthesiology, Experimental Anesthesiology Section, University Hospital of Tübingen, Tübingen, Germany
| | - A Raz
- Department of Anesthesiology, University of Wisconsin, Madison, WI, USA.,Department of Anesthesiology, Rambam Health Care Campus, Haifa, Israel
| | - B M Krause
- Department of Anesthesiology, University of Wisconsin, Madison, WI, USA
| | - C A Murphy
- Department of Anesthesiology, University of Wisconsin, Madison, WI, USA.,Physiology Graduate Training Program, University of Wisconsin, Madison, WI, USA
| | - M I Banks
- Department of Anesthesiology, University of Wisconsin, Madison, WI, USA
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Tang S, Powell EM, Zhu W, Lo FS, Erzurumlu RS, Xu S. Altered Forebrain Functional Connectivity and Neurotransmission in a Kinase-Inactive Met Mouse Model of Autism. Mol Imaging 2019; 18:1536012118821034. [PMID: 30799683 PMCID: PMC6322103 DOI: 10.1177/1536012118821034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 11/13/2018] [Accepted: 12/03/2018] [Indexed: 12/15/2022] Open
Abstract
MET, the gene encoding the tyrosine kinase receptor for hepatocyte growth factor, is a susceptibility gene for autism spectrum disorder (ASD). Genetically altered mice with a kinase-inactive Met offer a potential model for understanding neural circuit organization changes in autism. Here, we focus on the somatosensory thalamocortical circuitry because distinct somatosensory sensitivity phenotypes accompany ASD, and this system plays a major role in sensorimotor and social behaviors in mice. We employed resting-state functional magnetic resonance imaging and in vivo high-resolution proton MR spectroscopy to examine neuronal connectivity and neurotransmission of wild-type, heterozygous Met-Emx1, and fully inactive homozygous Met-Emx1 mice. Met-Emx1 brains showed impaired maturation of large-scale somatosensory network connectivity when compared with wild-type controls. Significant sex × genotype interaction in both network features and glutamate/gamma-aminobutyric acid (GABA) balance was observed. Female Met-Emx1 brains showed significant connectivity and glutamate/GABA balance changes in the somatosensory thalamocortical system when compared with wild-type brains. The glutamate/GABA ratio in the thalamus was correlated with the connectivity between the somatosensory cortex and the thalamus in heterozygous Met-Emx1 female brains. The findings support the hypothesis that aberrant functioning of the somatosensory thalamocortical system is at the core of the conspicuous somatosensory behavioral phenotypes observed in Met-Emx1 mice.
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Affiliation(s)
- Shiyu Tang
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Elizabeth M. Powell
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Wenjun Zhu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Fu-Sun Lo
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Reha S. Erzurumlu
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Su Xu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
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Gardner AT, Strathman HJ, Warren DJ, Walker RM. Impedance and Noise Characterizations of Utah and Microwire Electrode Arrays. ACTA ACUST UNITED AC 2018. [DOI: 10.1109/jerm.2018.2862417] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Michelson NJ, Kozai TDY. Isoflurane and ketamine differentially influence spontaneous and evoked laminar electrophysiology in mouse V1. J Neurophysiol 2018; 120:2232-2245. [PMID: 30067128 PMCID: PMC6295540 DOI: 10.1152/jn.00299.2018] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 07/23/2018] [Accepted: 07/25/2018] [Indexed: 12/20/2022] Open
Abstract
General anesthesia is ubiquitous in research and medicine, yet although the molecular mechanisms of anesthetics are well characterized, their ultimate influence on cortical electrophysiology remains unclear. Moreover, the influence that different anesthetics have on sensory cortexes at neuronal and ensemble scales is mostly unknown and represents an important gap in knowledge that has widespread relevance for neural sciences. To address this knowledge gap, this work explored the effects of isoflurane and ketamine/xylazine, two widely used anesthetic paradigms, on electrophysiological behavior in mouse primary visual cortex. First, multiunit activity and local field potentials were examined to understand how each anesthetic influences spontaneous activity. Then, the interlaminar relationships between populations of neurons at different cortical depths were studied to assess whether anesthetics influenced resting-state functional connectivity. Lastly, the spatiotemporal dynamics of visually evoked multiunit and local field potentials were examined to determine how each anesthetic alters communication of visual information. We found that isoflurane enhanced the rhythmicity of spontaneous ensemble activity at 10-40 Hz, which coincided with large increases in coherence between layer IV with superficial and deep layers. Ketamine preferentially increased local field potential power from 2 to 4 Hz, and the largest increases in coherence were observed between superficial and deep layers. Visually evoked responses across layers were diminished under isoflurane, and enhanced under ketamine anesthesia. These findings demonstrate that isoflurane and ketamine anesthesia differentially impact sensory processing in V1. NEW & NOTEWORTHY We directly compared electrophysiological responses in awake and anesthetized (isoflurane or ketamine) mice. We also proposed a method for quantifying and visualizing highly variable, evoked multiunit activity. Lastly, we observed distinct oscillatory responses to stimulus onset and offset in awake and isoflurane-anesthetized mice.
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Affiliation(s)
- Nicholas J Michelson
- Department of Bioengineering, University of Pittsburgh , Pittsburgh, Pennsylvania
| | - Takashi D Y Kozai
- Department of Bioengineering, University of Pittsburgh , Pittsburgh, Pennsylvania
- Center for the Neural Basis of Cognition, University of Pittsburgh , Pittsburgh, Pennsylvania
- Center for Neuroscience, University of Pittsburgh , Pittsburgh, Pennsylvania
- McGowan Institute of Regenerative Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania
- NeuroTech Center, University of Pittsburgh Brain Institute , Pittsburgh, Pennsylvania
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45
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Mickey BJ, White AT, Arp AM, Leonardi K, Torres MM, Larson AL, Odell DH, Whittingham SA, Beck MM, Jessop JE, Sakata DJ, Bushnell LA, Pierson MD, Solzbacher D, Kendrick EJ, Weeks HR, Light AR, Light KC, Tadler SC. Propofol for Treatment-Resistant Depression: A Pilot Study. Int J Neuropsychopharmacol 2018; 21:1079-1089. [PMID: 30260415 PMCID: PMC6276046 DOI: 10.1093/ijnp/pyy085] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 09/25/2018] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND We hypothesized that propofol, a unique general anesthetic that engages N-methyl-D-aspartate and gamma-aminobutyric acid receptors, has antidepressant properties. This open-label trial was designed to collect preliminary data regarding the feasibility, tolerability, and efficacy of deep propofol anesthesia for treatment-resistant depression. METHODS Ten participants with moderate-to-severe medication-resistant depression (age 18-45 years and otherwise healthy) each received a series of 10 propofol infusions. Propofol was dosed to strongly suppress electroencephalographic activity for 15 minutes. The primary depression outcome was the 24-item Hamilton Depression Rating Scale. Self-rated depression scores were compared with a group of 20 patients who received electroconvulsive therapy. RESULTS Propofol treatments were well tolerated by all subjects. No serious adverse events occurred. Montreal Cognitive Assessment scores remained stable. Hamilton scores decreased by a mean of 20 points (range 0-45 points), corresponding to a mean 58% improvement from baseline (range 0-100%). Six of the 10 subjects met the criteria for response (>50% improvement). Self-rated depression improved similarly in the propofol group and electroconvulsive therapy group. Five of the 6 propofol responders remained well for at least 3 months. In posthoc analyses, electroencephalographic measures predicted clinical response to propofol. CONCLUSIONS These findings demonstrate that high-dose propofol treatment is feasible and well tolerated by individuals with treatment-resistant depression who are otherwise healthy. Propofol may trigger rapid, durable antidepressant effects similar to electroconvulsive therapy but with fewer side effects. Controlled studies are warranted to further evaluate propofol's antidepressant efficacy and mechanisms of action. ClinicalTrials.gov: NCT02935647.
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Affiliation(s)
- Brian J Mickey
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
- Department of Psychiatry, University of Michigan, Ann Arbor, MI
- Correspondence: Brian J. Mickey, MD, PhD, 501 Chipeta Way, Salt Lake City, Utah, 84108 ()
| | - Andrea T White
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | - Anna M Arp
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
| | - Kolby Leonardi
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
| | - Marina M Torres
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
| | - Adam L Larson
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | - David H Odell
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | | | - Michael M Beck
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | - Jacob E Jessop
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | - Derek J Sakata
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | - Lowry A Bushnell
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
| | - Matthew D Pierson
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
| | - Daniela Solzbacher
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
| | - E Jeremy Kendrick
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
| | - Howard R Weeks
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | - Alan R Light
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | - Kathleen C Light
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | - Scott C Tadler
- Department of Psychiatry, University Neuropsychiatric Institute, University of Utah, Salt Lake City, UT
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
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46
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Chartier M, Malissin I, Tannous S, Labat L, Risède P, Mégarbane B, Chevillard L. Baclofen-induced encephalopathy in overdose - Modeling of the electroencephalographic effect/concentration relationships and contribution of tolerance in the rat. Prog Neuropsychopharmacol Biol Psychiatry 2018; 86:131-139. [PMID: 29782961 DOI: 10.1016/j.pnpbp.2018.05.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/16/2018] [Accepted: 05/17/2018] [Indexed: 12/31/2022]
Abstract
Baclofen, a γ-amino-butyric acid type-B receptor agonist with exponentially increased use at high-dose to facilitate abstinence in chronic alcoholics, is responsible for increasing poisonings. Baclofen overdose may induce severe encephalopathy and electroencephalographic (EEG) abnormalities. Whether prior prolonged baclofen treatment may influence the severity of baclofen-induced encephalopathy in overdose has not been established. We designed a rat study to characterize baclofen-induced encephalopathy, correlate its severity with plasma concentrations and investigate the contribution of tolerance. Baclofen-induced encephalopathy was assessed using continuous EEG and scored based on a ten-grade scale. Following the administration by gavage of 116 mg/kg baclofen, EEG rapidly and steadily impaired resulting in the successive onset of deepening sleep followed by generalized periodic epileptiform discharges and burst-suppressions. Thereafter, encephalopathy progressively recovered following similar phases in reverse. Periodic triphasic sharp waves, non-convulsive status epilepticus and even isoelectric signals were observed at the most critical stages. Prior repeated baclofen administration resulted in reduced severity (peak: grade 7 versus 9; peak effect length: 382 ± 40 versus 123 ± 14 min, P = 0.008) and duration of encephalopathy (18 versus > 24 h, P = 0.0007), supporting the acquisition of tolerance. The relationship between encephalopathy severity and plasma baclofen concentrations fitted a sigmoidal Emax model with an anticlockwise hysteresis loop suggesting a hypothetical biophase site of action. The baclofen concentration producing a response equivalent to 50% of Emax was significantly reduced (8947 μg/L, ±11.3% versus 12,728 μg/L, ±24.0% [mean, coefficient of variation], P = 0.03) with prior prolonged baclofen administration. In conclusion, baclofen overdose induces early-onset and prolonged marked encephalopathy that is significantly attenuated by prior repeated baclofen treatment. Our findings suggest a possible role for the blood-brain barrier in the development of tolerance; however, its definitive involvement remains to be demonstrated.
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Affiliation(s)
| | - Isabelle Malissin
- Department of Medical and Toxicological Critical Care, Lariboisière Hospital, Paris-Diderot University, Paris, France
| | - Salma Tannous
- Inserm UMRS-1144, Paris-Descartes University, Paris, France
| | - Laurence Labat
- Inserm UMRS-1144, Paris-Descartes University, Paris, France; Pharmacokinetics and Pharmaco-chemistry Unit, Cochin Hospital, Paris, France; Laboratory of Toxicology, Lariboisière Hospital, Paris, France
| | | | - Bruno Mégarbane
- Inserm UMRS-1144, Paris-Descartes University, Paris, France; Department of Medical and Toxicological Critical Care, Lariboisière Hospital, Paris-Diderot University, Paris, France.
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Stenroos P, Paasonen J, Salo RA, Jokivarsi K, Shatillo A, Tanila H, Gröhn O. Awake Rat Brain Functional Magnetic Resonance Imaging Using Standard Radio Frequency Coils and a 3D Printed Restraint Kit. Front Neurosci 2018; 12:548. [PMID: 30177870 PMCID: PMC6109636 DOI: 10.3389/fnins.2018.00548] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 07/20/2018] [Indexed: 11/13/2022] Open
Abstract
Functional magnetic resonance imaging (fMRI) is a powerful noninvasive tool for studying spontaneous resting state functional connectivity (RSFC) in laboratory animals. Brain function can be significantly affected by generally used anesthetics, however, rendering the need for awake imaging. Only a few different awake animal habituation protocols have been presented, and there is a critical need for practical and improved low-stress techniques. Here we demonstrate a novel restraint approach for awake rat RSFC studies. Our custom-made 3D printed restraint kit is compatible with a standard Bruker Biospin MRI rat bed, rat brain receiver coil, and volume transmitter coil. We also implemented a progressive habituation protocol aiming to minimize the stress experienced by the rats, and compared RSFC between awake, lightly sedated, and isoflurane-anesthetized rats. Our results demonstrated that the 3D printed restraint kit was suitable for RSFC studies of awake rats. During the short 4-day habituation period, the plasma corticosterone concentration, movement, and heart rate, which were measured as stress indicators, decreased significantly, indicating adaptation to the restraint protocol. Additionally, 10 days after the awake MRI session, rats exhibited no signs of depression or anxiety based on open-field and sucrose preference behavioral tests. The RSFC data revealed significant changes in the thalamo-cortical and cortico-cortical networks between the awake, lightly sedated, and anesthetized groups, emphasizing the need for awake imaging. The present work demonstrates the feasibility of our custom-made 3D printed restraint kit. Using this kit, we found that isoflurane markedly affected brain connectivity compared with that in awake rats, and that the effect was less pronounced, but still significant, when light isoflurane sedation was used instead.
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Affiliation(s)
- Petteri Stenroos
- Kuopio Biomedical Imaging Unit, A.I.V. Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jaakko Paasonen
- Kuopio Biomedical Imaging Unit, A.I.V. Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Raimo A Salo
- Kuopio Biomedical Imaging Unit, A.I.V. Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Kimmo Jokivarsi
- Kuopio Biomedical Imaging Unit, A.I.V. Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Artem Shatillo
- Charles River Discovery Research Services Finland Oy, Kuopio, Finland
| | - Heikki Tanila
- Kuopio Biomedical Imaging Unit, A.I.V. Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Olli Gröhn
- Kuopio Biomedical Imaging Unit, A.I.V. Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
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48
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Song C, Piscopo DM, Niell CM, Knöpfel T. Cortical signatures of wakeful somatosensory processing. Sci Rep 2018; 8:11977. [PMID: 30097603 PMCID: PMC6086870 DOI: 10.1038/s41598-018-30422-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 07/24/2018] [Indexed: 12/13/2022] Open
Abstract
Sensory inputs carry critical information for the survival of an organism. In mice, tactile information conveyed by the whiskers is of high behavioural relevance, and is broadcasted across cortical areas beyond the primary somatosensory cortex. Mesoscopic voltage sensitive dye imaging (VSDI) of cortical population response to whisker stimulations has shown that seemingly 'simple' sensory stimuli can have extended impact on cortical circuit dynamics. Here we took advantage of genetically encoded voltage indicators (GEVIs) that allow for cell type-specific monitoring of population voltage dynamics in a chronic dual-hemisphere transcranial windowed mouse preparation to directly compare the cortex-wide broadcasting of sensory information in wakening (lightly anesthetized to sedated) and awake mice. Somatosensory-evoked cortex-wide dynamics is altered across brain states, with anatomically sequential hyperpolarising activity observed in the awake cortex. GEVI imaging revealed cortical activity maps with increased specificity, high spatial coverage, and at the timescale of cortical information processing.
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Affiliation(s)
- Chenchen Song
- Laboratory for Neuronal Circuit Dynamics, Imperial College London, W12 0NN, London, UK
| | - Denise M Piscopo
- Institute of Neuroscience, University of Oregon, Eugene, Oregon, 97403, USA
| | - Cristopher M Niell
- Institute of Neuroscience, University of Oregon, Eugene, Oregon, 97403, USA
| | - Thomas Knöpfel
- Laboratory for Neuronal Circuit Dynamics, Imperial College London, W12 0NN, London, UK. .,Centre for Neurotechnology, Institute of Biomedical Engineering, Imperial College London, SW7 2AZ, London, UK.
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49
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Luan L, Sullender CT, Li X, Zhao Z, Zhu H, Wei X, Xie C, Dunn AK. Nanoelectronics enabled chronic multimodal neural platform in a mouse ischemic model. J Neurosci Methods 2018; 295:68-76. [PMID: 29203409 PMCID: PMC5801157 DOI: 10.1016/j.jneumeth.2017.12.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 11/22/2017] [Accepted: 12/01/2017] [Indexed: 01/22/2023]
Abstract
BACKGROUND Despite significant advancements of optical imaging techniques for mapping hemodynamics in small animal models, it remains challenging to combine imaging with spatially resolved electrical recording of individual neurons especially for longitudinal studies. This is largely due to the strong invasiveness to the living brain from the penetrating electrodes and their limited compatibility with longitudinal imaging. NEW METHOD We implant arrays of ultraflexible nanoelectronic threads (NETs) in mice for neural recording both at the brain surface and intracortically, which maintain great tissue compatibility chronically. By mounting a cranial window atop of the NET arrays that allows for chronic optical access, we establish a multimodal platform that combines spatially resolved electrical recording of neural activity and laser speckle contrast imaging (LSCI) of cerebral blood flow (CBF) for longitudinal studies. RESULTS We induce peri-infarct depolarizations (PIDs) by targeted photothrombosis, and show the ability to detect its occurrence and propagation through spatiotemporal variations in both extracellular potentials and CBF. We also demonstrate chronic tracking of single-unit neural activity and CBF over days after photothrombosis, from which we observe reperfusion and increased firing rates. COMPARISON WITH EXISTING METHOD(S) This multimodal platform enables simultaneous mapping of neural activity and hemodynamic parameters at the microscale for quantitative, longitudinal comparisons with minimal perturbation to the baseline neurophysiology. CONCLUSION The ability to spatiotemporally resolve and chronically track CBF and neural electrical activity in the same living brain region has broad applications for studying the interplay between neural and hemodynamic responses in health and in cerebrovascular and neurological pathologies.
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Affiliation(s)
- Lan Luan
- Department of Biomedical Engineering, The University of Texas at Austin, United States; Department of Physics, The University of Texas at Austin, United States.
| | - Colin T Sullender
- Department of Biomedical Engineering, The University of Texas at Austin, United States
| | - Xue Li
- Department of Biomedical Engineering, The University of Texas at Austin, United States
| | - Zhengtuo Zhao
- Department of Biomedical Engineering, The University of Texas at Austin, United States
| | - Hanlin Zhu
- Department of Biomedical Engineering, The University of Texas at Austin, United States
| | - Xiaoling Wei
- Department of Biomedical Engineering, The University of Texas at Austin, United States
| | - Chong Xie
- Department of Biomedical Engineering, The University of Texas at Austin, United States.
| | - Andrew K Dunn
- Department of Biomedical Engineering, The University of Texas at Austin, United States.
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50
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McKillop LE, Vyazovskiy VV. Sleep- and Wake-Like States in Small Networks In Vivo and In Vitro. Handb Exp Pharmacol 2018; 253:97-121. [PMID: 30443784 DOI: 10.1007/164_2018_174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Wakefulness and sleep are highly complex and heterogeneous processes, involving multiple neurotransmitter systems and a sophisticated interplay between global and local networks of neurons and non-neuronal cells. Macroscopic approaches applied at the level of the whole organism, view sleep as a global behaviour and allow for investigation into aspects such as the effects of insufficient or disrupted sleep on cognitive function, metabolism, thermoregulation and sensory processing. While significant progress has been achieved using such large-scale approaches, the inherent complexity of sleep-wake regulation has necessitated the development of methods which tackle specific aspects of sleep in isolation. One way this may be achieved is by investigating specific cellular or molecular phenomena in the whole organism in situ, either during spontaneous or induced sleep-wake states. This approach has greatly advanced our knowledge about the electrophysiology and pharmacology of ion channels, specific receptors, intracellular pathways and the small networks implicated in the control and regulation of the sleep-wake cycle. Importantly though, there are a variety of external and internal factors that influence global behavioural states which are difficult to control for using these approaches. For this reason, over the last few decades, ex vivo experimental models have become increasingly popular and have greatly advanced our understanding of many fundamental aspects of sleep, including the neuroanatomy and neurochemistry of sleep states, sleep regulation, the origin and dynamics of specific sleep oscillations, network homeostasis as well as the functional roles of sleep. This chapter will focus on the use of small neuronal networks as experimental models and will highlight the most significant and novel insights these approaches have provided.
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Affiliation(s)
- Laura E McKillop
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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