1
|
Yavuz M, İyiköşker P, Mutlu N, Kiliçparlar S, Şalci ÖH, Dolu G, Kaymakçilar EN, Akkol S, Onat F. Dexmedetomidine, an alpha 2A receptor agonist, triggers seizures unilaterally in GAERS during the pre-epileptic phase: does the onset of spike-and-wave discharges occur in a focal manner? Front Neurol 2023; 14:1231736. [PMID: 38146441 PMCID: PMC10749324 DOI: 10.3389/fneur.2023.1231736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 11/13/2023] [Indexed: 12/27/2023] Open
Abstract
Introduction The genetic absence epilepsy rat from Strasbourg (GAERS) is a rat model for infantile absence epilepsy with spike-and-wave discharges (SWDs). This study aimed to investigate the potential of alpha 2A agonism to induce seizures during the pre-epileptic period in GAERS rats. Methods Stereotaxic surgery was performed on male pups and adult GAERS rats to implant recording electrodes in the frontoparietal cortices (right/left) under anesthesia (PN23-26). Following the recovery period, pup GAERS rats were subjected to electroencephalography (EEG) recordings for 2 h. Before the injections, pup epileptiform activity was examined using baseline EEG data. Dexmedetomidine was acutely administered at 0.6 mg/kg to pup GAERS rats 2-3 days after the surgery and once during the post-natal (PN) days 25-29. Epileptiform activities before injections triggered unilateral SWDs and induced sleep durations, and power spectral density was evaluated based on EEG traces. Results The most prominent finding of this study is that unilateral SWD-like activities were induced in 47% of the animals with the intraperitoneal dexmedetomidine injection. The baseline EEGs of pup GAERS rats had no SWDs as expected since they are in the pre-epileptic period but showed low-amplitude non-rhythmic epileptiform activity. There was no difference in the duration of epileptiform activities between the basal EEG groups and DEX-injected unilateral SWD-like-exhibiting and non-SWD-like activities groups; however, the sleep duration of the unilateral SWD-like-exhibiting group was shorter. Power spectrum density (PSD) results revealed that the 1.75-Hz power in the left hemisphere peaks significantly higher than in the right. Discussion As anticipated, pup GAERS rats in the pre-epileptic stage showed no SWDs. Nevertheless, they exhibited sporadic epileptiform activities. Specifically, dexmedetomidine induced SWD-like activities solely within the left hemisphere. These observations imply that absence seizures might originate unilaterally in the left cortex due to α2AAR agonism. Additional research is necessary to explore the precise cortical focal point of this activity.
Collapse
Affiliation(s)
- Melis Yavuz
- Department of Pharmacology, Faculty of Pharmacy, Acibadem Mehmet Ali Aydinlar University, Istanbul, Türkiye
| | - Pelin İyiköşker
- Faculty of Pharmacy, Acibadem Mehmet Ali Aydinlar University, Istanbul, Türkiye
| | - Nursima Mutlu
- Department of Biotechnology and Genetics, Institute of Science, Istanbul University, Istanbul, Türkiye
| | - Serra Kiliçparlar
- Faculty of Pharmacy, Acibadem Mehmet Ali Aydinlar University, Istanbul, Türkiye
| | - Öykü Hazal Şalci
- Faculty of Pharmacy, Acibadem Mehmet Ali Aydinlar University, Istanbul, Türkiye
| | - Gökçen Dolu
- Faculty of Pharmacy, Acibadem Mehmet Ali Aydinlar University, Istanbul, Türkiye
| | | | - Serdar Akkol
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Filiz Onat
- Department of Medical Pharmacology, School of Medicine, Acibadem Mehmet Ali Aydinlar University, Istanbul, Türkiye
- Institute of Neurosciences, Acibadem Mehmet Ali Aydinlar University, Istanbul, Türkiye
| |
Collapse
|
2
|
Lindquist BE, Timbie C, Voskobiynyk Y, Paz JT. Thalamocortical circuits in generalized epilepsy: Pathophysiologic mechanisms and therapeutic targets. Neurobiol Dis 2023; 181:106094. [PMID: 36990364 PMCID: PMC10192143 DOI: 10.1016/j.nbd.2023.106094] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/02/2023] [Accepted: 03/19/2023] [Indexed: 03/29/2023] Open
Abstract
Generalized epilepsy affects 24 million people globally; at least 25% of cases remain medically refractory. The thalamus, with widespread connections throughout the brain, plays a critical role in generalized epilepsy. The intrinsic properties of thalamic neurons and the synaptic connections between populations of neurons in the nucleus reticularis thalami and thalamocortical relay nuclei help generate different firing patterns that influence brain states. In particular, transitions from tonic firing to highly synchronized burst firing mode in thalamic neurons can cause seizures that rapidly generalize and cause altered awareness and unconsciousness. Here, we review the most recent advances in our understanding of how thalamic activity is regulated and discuss the gaps in our understanding of the mechanisms of generalized epilepsy syndromes. Elucidating the role of the thalamus in generalized epilepsy syndromes may lead to new opportunities to better treat pharmaco-resistant generalized epilepsy by thalamic modulation and dietary therapy.
Collapse
Affiliation(s)
- Britta E Lindquist
- UCSF Department of Neurology, Division of Neurocritical Care, United States of America; UCSF Department of Neurology, Division of Pediatric Epilepsy, United States of America; UCSF Department of Neurology, United States of America
| | - Clare Timbie
- Gladstone Institute of Neurological Disease, United States of America; UCSF Department of Neurology, Division of Pediatric Epilepsy, United States of America; UCSF Department of Neurology, United States of America
| | - Yuliya Voskobiynyk
- Gladstone Institute of Neurological Disease, United States of America; UCSF Department of Neurology, United States of America
| | - Jeanne T Paz
- Gladstone Institute of Neurological Disease, United States of America; UCSF Department of Neurology, United States of America; Kavli Institute for Fundamental Neuroscience, UCSF, United States of America.
| |
Collapse
|
3
|
Sysoeva MV, Kuznetsova GD, Sysoev IV, Ngomba RT, Vinogradova LV, Grishchenko AA, van Rijn CM, van Luijtelaar G. NETWORK ANALYSIS REVEALS A ROLE OF THE HIPPOCAMPUS IN ABSENCE SEIZURES: THE EFFECTS OF A CANNABINOID AGONIST. Epilepsy Res 2023; 192:107135. [PMID: 37023553 DOI: 10.1016/j.eplepsyres.2023.107135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 02/27/2023] [Accepted: 03/30/2023] [Indexed: 04/04/2023]
Abstract
The role of the hippocampus (Hp) in absence epileptic networks and the effect of endocannabinoid system on this network remain enigmatic. Here, using adapted nonlinear Granger causality, we compared the differences in network strength in four intervals (baseline or interictal, preictal, ictal and postictal) in two hours before (Epoch 1) and six hours (epochs 2, 3 and 4) after the administration of three different doses of the endocannabinoid agonist WIN55,212-2 (WIN) or solvent. Local field potentials were recorded for eight hours in 23 WAG/Rij rats in the Frontal (FC), Parietal PC), Occipital Cortex (OC) and in the hippocampus (Hp). The four intervals were visually marked by an expert neurophysiologist and the strength of couplings between electrode pairs were calculated in both directions. Ictally, a strong decrease in coupling strength was found between Hp and FC, as well as a large increase bidirectionally between PC and FC and unidirectionally from FC and PC to OC, and from FC to Hp over all epochs. The highest dose of WIN increased the couplings strength from FC to Hp and from OC to PC during 4 and 2 hr respectively in all intervals, and decreased the FC to PC coupling strength postictally in epoch 2. A single rat showed generalized convulsive seizures after the highest dose: this rat shared not only coupling changes with the other rats in the same condition, but showed many more. WIN reduced SWD number in epoch 2 and 3, their mean duration increased in epochs 3 and 4. Conclusions:during SWDs FC and PC are strongly coupled and drive OC, while at the same time the influence of Hp to FC is diminished. The first is in agreement with the cortical focus theory, the latter demonstrates an involvement of the hippocampus in SWD occurrence and that ictally the hippocampal control of the cortico-thalamo-cortical system is lost. WIN causes dramatic network changes which have major consequences for the decrease of SWDs, the occurrence of convulsive seizures, and the normal cortico-cortical and cortico-hippocampal interactions.
Collapse
|
4
|
Luyao Yan A, Honghui Zhang B, Zhongkui Sun C, Zilu Cao D, Zhuan Shen E, Yuzhi Zhao F. Mechanism analysis for excitatory interneurons dominating poly-spike wave and optimization of electrical stimulation. CHAOS (WOODBURY, N.Y.) 2022; 32:033110. [PMID: 35364840 DOI: 10.1063/5.0076439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
In addition to inhibitory interneurons, there exist excitatory interneurons (EINs) in the cortex, which mainly have excitatory projections to pyramidal neurons. In this study, we improve a thalamocortical model by introducing EIN, investigate the dominant role of EIN in generating spike and slow wave discharges (SWDs), and consider a non-rectangular pulse to control absence seizures. First, we display here that the improved model can reproduce typical SWDs of absence seizures. Moreover, we focus on the function of EIN by means of bifurcation analysis and find that EIN can induce transition behaviors under Hopf-type and fold limit cycle bifurcations. Specifically, the system has three stable solutions composing a tri-stable region. In this region, there are three attraction basins, which hints that external stimulation can drive the system trajectory from one basin to another, thereby eliminating abnormal oscillations. Furthermore, we compare the increasing ramp with rectangular pulse and optimize stimulation waveforms from the perspective of electrical charges input. The controlling role of the single increasing ramp to absence seizures is remarkable and the optimal stimulus parameters have been found theoretically. This work provides a computational model containing EIN and a theoretical basis for future physiological experiments and clinical research studies.
Collapse
Affiliation(s)
- A Luyao Yan
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi'an, Shaanxi 710129, China
| | - B Honghui Zhang
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi'an, Shaanxi 710129, China
| | - C Zhongkui Sun
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi'an, Shaanxi 710129, China
| | - D Zilu Cao
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi'an, Shaanxi 710129, China
| | - E Zhuan Shen
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi'an, Shaanxi 710129, China
| | - F Yuzhi Zhao
- School of Mathematics and Statistics, Northwestern Polytechnical University, Xi'an, Shaanxi 710129, China
| |
Collapse
|
5
|
Deshpande G, Wang Y, Robinson J. Resting state fMRI connectivity is sensitive to laminar connectional architecture in the human brain. Brain Inform 2022; 9:2. [PMID: 35038072 PMCID: PMC8764001 DOI: 10.1186/s40708-021-00150-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 12/28/2021] [Indexed: 11/10/2022] Open
Abstract
Previous invasive studies indicate that human neocortical graymatter contains cytoarchitectonically distinct layers, with notable differences in their structural connectivity with the rest of the brain. Given recent improvements in the spatial resolution of anatomical and functional magnetic resonance imaging (fMRI), we hypothesize that resting state functional connectivity (FC) derived from fMRI is sensitive to layer-specific thalamo-cortical and cortico-cortical microcircuits. Using sub-millimeter resting state fMRI data obtained at 7 T, we found that: (1) FC between the entire thalamus and cortical layers I and VI was significantly stronger than between the thalamus and other layers. Furthermore, FC between somatosensory thalamus (ventral posterolateral nucleus, VPL) and layers IV, VI of the primary somatosensory cortex were stronger than with other layers; (2) Inter-hemispheric cortico-cortical FC between homologous regions in superficial layers (layers I-III) was stronger compared to deep layers (layers V-VI). These findings are in agreement with structural connections inferred from previous invasive studies that showed that: (i) M-type neurons in the entire thalamus project to layer-I; (ii) Pyramidal neurons in layer-VI target all thalamic nuclei, (iii) C-type neurons in the VPL project to layer-IV and receive inputs from layer-VI of the primary somatosensory cortex, and (iv) 80% of collosal projecting neurons between homologous cortical regions connect superficial layers. Our results demonstrate for the first time that resting state fMRI is sensitive to structural connections between cortical layers (previously inferred through invasive studies), specifically in thalamo-cortical and cortico-cortical networks.
Collapse
Affiliation(s)
- Gopikrishna Deshpande
- AU MRI Research Center, Department of Electrical & Computer Engineering, Auburn University, 560 Devall Dr, Suite 266D, Auburn, AL, 36849, USA. .,Department of Psychological Sciences, Auburn University, Auburn, AL, USA. .,Alabama Advanced Imaging Consortium, Birmingham, AL, USA. .,Center for Neuroscience, Auburn University, Auburn, AL, USA. .,Key Laboratory for Learning and Cognition, School of Psychology, Capital Normal University, Beijing, China. .,Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore, India. .,Centre for Brain Research, Indian Institute of Science, Bangalore, India.
| | - Yun Wang
- AU MRI Research Center, Department of Electrical & Computer Engineering, Auburn University, 560 Devall Dr, Suite 266D, Auburn, AL, 36849, USA.,Department of Psychiatry, Columbia University, New York, NY, USA
| | - Jennifer Robinson
- AU MRI Research Center, Department of Electrical & Computer Engineering, Auburn University, 560 Devall Dr, Suite 266D, Auburn, AL, 36849, USA.,Department of Psychological Sciences, Auburn University, Auburn, AL, USA.,Alabama Advanced Imaging Consortium, Birmingham, AL, USA.,Center for Neuroscience, Auburn University, Auburn, AL, USA
| |
Collapse
|
6
|
Dynamical mesoscale model of absence seizures in genetic models. PLoS One 2020; 15:e0239125. [PMID: 32991590 PMCID: PMC7524004 DOI: 10.1371/journal.pone.0239125] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 08/31/2020] [Indexed: 12/20/2022] Open
Abstract
A mesoscale network model is proposed for the development of spike and wave discharges (SWDs) in the cortico-thalamo-cortical (C-T-C) circuit. It is based on experimental findings in two genetic models of childhood absence epilepsy–rats of WAG/Rij and GAERS strains. The model is organized hierarchically into two levels (brain structures and individual neurons) and composed of compartments for representation of somatosensory cortex, reticular and ventroposteriomedial thalamic nuclei. The cortex and the two thalamic compartments contain excitatory and inhibitory connections between four populations of neurons. Two connected subnetworks both including relevant parts of a C-T-C network responsible for SWD generation are modelled: a smaller subnetwork for the focal area in which the SWD generation can take place, and a larger subnetwork for surrounding areas which can be only passively involved into SWDs, but which is mostly responsible for normal brain activity. This assumption allows modeling of both normal and SWD activity as a dynamical system (no noise is necessary), providing reproducibility of results and allowing future analysis by means of theory of dynamical system theories. The model is able to reproduce most time-frequency changes in EEG activity accompanying the transition from normal to epileptiform activity and back. Three different mechanisms of SWD initiation reported previously in experimental studies were successfully reproduced in the model. The model incorporates also a separate mechanism for the maintenance of SWDs based on coupling analysis from experimental data. Finally, the model reproduces the possibility to stop ongoing SWDs with high frequency electrical stimulation, as described in the literature.
Collapse
|
7
|
Doǧan E, Aygün H, Arslan G, Rzayev E, Avcı B, Ayyıldız M, Ağar E. The Role of NMDA Receptors in the Effect of Purinergic P2X7 Receptor on Spontaneous Seizure Activity in WAG/Rij Rats With Genetic Absence Epilepsy. Front Neurosci 2020; 14:414. [PMID: 32435183 PMCID: PMC7218146 DOI: 10.3389/fnins.2020.00414] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 04/06/2020] [Indexed: 12/14/2022] Open
Abstract
P2X7 receptors (P2X7Rs) are ATP sensitive cation channels and have been shown to be effective in various epilepsy models. Absence epilepsy is a type of idiopathic, generalized, non-convulsive epilepsy. Limited data exist on the role of P2X7Rs and no data has been reported regarding the interaction between P2X7Rs and glutamate receptor NMDA in absence epilepsy. Thus, this study was designed to investigate the role of P2X7 and NMDA receptors and their possible interaction in WAG/Rij rats with absence epilepsy. Permanent cannula and electrodes were placed on the skulls of the animals. After the healing period of the electrode and cannula implantation, ECoG recordings were obtained during 180 min before and after drug injections. P2X7R agonist BzATP, at doses of 50 μg and 100 μg (intracerebroventricular; i.c.v.) and antagonist A-438079, at doses of 20 μg and 40 μg (i.c.v.) were administered alone or prior to memantine (5 mg/kg, intraperitoneal; i.p.) injection. The total number (in every 20 min), the mean duration, and the amplitude of spike-wave discharges (SWDs) were calculated and compared. Rats were decapitated and the right and left hemisphere, cerebellum, and brainstem were separated for the measurements of the advanced oxidation protein product (AOPP), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), glutathione peroxide (GPx), and glutathione reductase (GR). BzATP and A-438079 did not alter measured SWDs parameters, whereas memantine reduced them, which is considered anticonvulsant. BzATP did not alter the anticonvulsant effect of memantine, while A-438079 decreased the effect of memantine. Administration of BzATP increased the levels of SOD and GR in cerebrum hemispheres. A-438079 did not alter any of the biochemical parameters. Memantine reduced the levels of MDA, GSH, and GR while increased the level of CAT in the cerebrum. Administration of BzATP before memantine abolished the effect of memantine on MDA levels. The evidence from this study suggests that P2X7Rs does not directly play a role in the formation of absence seizures. P2X7Rs agonist, reduced the antioxidant activity of memantine whereas agonist of P2X7Rs reduced the anticonvulsant action of memantine, suggesting a partial interaction between P2X7 and NMDA receptors in absence epilepsy model.
Collapse
Affiliation(s)
- Elif Doǧan
- Department of Physiology, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Hatice Aygün
- Department of Physiology, Faculty of Medicine, Gaziosmanpasa University, Tokat, Turkey
| | - Gökhan Arslan
- Department of Physiology, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Emil Rzayev
- Department of Clinical Biochemistry, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Bahattin Avcı
- Department of Clinical Biochemistry, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Mustafa Ayyıldız
- Department of Physiology, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Erdal Ağar
- Department of Physiology, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| |
Collapse
|
8
|
Ossenblok P, van Houdt P, Colon A, Stroink H, van Luijtelaar G. A network approach to investigate the bi-hemispheric synchrony in absence epilepsy. Clin Neurophysiol 2019; 130:1611-1619. [PMID: 31319290 DOI: 10.1016/j.clinph.2019.05.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/11/2019] [Accepted: 05/22/2019] [Indexed: 11/24/2022]
|
9
|
Yang DP, Robinson PA. Unified analysis of global and focal aspects of absence epilepsy via neural field theory of the corticothalamic system. Phys Rev E 2019; 100:032405. [PMID: 31639915 DOI: 10.1103/physreve.100.032405] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Indexed: 06/10/2023]
Abstract
Absence epilepsy is characterized by a sudden paroxysmal loss of consciousness accompanied by oscillatory activity propagating over many brain areas. Although primary generalized absence seizures are supported by the global corticothalamic system, converging experimental evidence supports a focal theory of absence epilepsy. Here a physiology-based corticothalamic model is investigated with spatial heterogeneity due to focal epilepsy to unify global and focal aspects of absence epilepsy. Numeric and analytic calculations are employed to investigate the emergent spatiotemporal dynamics as well as their underlying dynamical mechanisms. They can be categorized into three scenarios: suppressed epilepsy, focal seizures, or generalized seizures, as summarized from a phase diagram vs focal width and characteristic axon range. The corresponding temporal frequencies and spatial extents of cortical waves in generalized seizures and focal seizures agree well with experimental observations of global and focal aspects of absence epilepsy, respectively. The emergence of the spatiotemporal dynamics corresponding to focal seizures provides a biophysical explanation of the temporally higher frequency but spatially more localized cortical waves observed in genetic rat models that display characteristics of human absence epilepsy. Predictions are also presented for further experimental test.
Collapse
Affiliation(s)
- Dong-Ping Yang
- School of Physics, University of Sydney, New South Wales 2006, Australia and Center for Integrative Brain Function, University of Sydney, New South Wales 2006, Australia
| | - P A Robinson
- School of Physics, University of Sydney, New South Wales 2006, Australia and Center for Integrative Brain Function, University of Sydney, New South Wales 2006, Australia
| |
Collapse
|
10
|
Abstract
New treatment approaches in epilepsy - such as novel antiepileptic drugs and neurostimulation - generally at first are assessed in animal models in regard to feasibility, efficacy and safety. The aim of this review was to elucidate and summarize the available literature on in vivo experimental studies on radiofrequency thermoablation and laser interstitial thermal therapy. We have found two in vivo studies on radiofrequency ablation of an acute seizure focus, one assessed the conventional transcranial and the other one a transvenous approach. All other studies focused on technical issues of functional ablation of brain structures assessing parameters such as maximal temperature and duration of thermal ablation as well as electrode devices. As the concept of functional ablation is evident - destruction of the epileptogenic focus as performed in "open" resective surgery - general "proof of concept" experiments do not seem to be necessary.
Collapse
Affiliation(s)
- Martin Holtkamp
- Epilepsy-Center Berlin-Brandenburg, Department of Neurology, Charité - Universitätsmedizin Berlin, Germany.
| | - Lars Büntjen
- Department of Stereotactic Neurosurgery, University Hospital Magdeburg, Germany
| | | |
Collapse
|
11
|
Pathophysiology of absence epilepsy: Insights from genetic models. Neurosci Lett 2018; 667:53-65. [DOI: 10.1016/j.neulet.2017.02.035] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 02/08/2017] [Accepted: 02/12/2017] [Indexed: 11/21/2022]
|
12
|
Medvedeva TM, Sysoeva MV, van Luijtelaar G, Sysoev IV. Modeling spike-wave discharges by a complex network of neuronal oscillators. Neural Netw 2018; 98:271-282. [DOI: 10.1016/j.neunet.2017.12.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 10/02/2017] [Accepted: 12/04/2017] [Indexed: 10/18/2022]
|
13
|
Hall SP, Traub RD, Adams NE, Cunningham MO, Schofield I, Jenkins AJ, Whittington MA. Enhanced interlaminar excitation or reduced superficial layer inhibition in neocortex generates different spike-and-wave-like electrographic events in vitro. J Neurophysiol 2018; 119:49-61. [PMID: 28954894 PMCID: PMC5866469 DOI: 10.1152/jn.00516.2017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 09/26/2017] [Accepted: 09/26/2017] [Indexed: 12/19/2022] Open
Abstract
Acute in vitro models have revealed a great deal of information about mechanisms underlying many types of epileptiform activity. However, few examples exist that shed light on spike-and-wave (SpW) patterns of pathological activity. SpW are seen in many epilepsy syndromes, both generalized and focal, and manifest across the entire age spectrum. They are heterogeneous in terms of their severity, symptom burden, and apparent anatomical origin (thalamic, neocortical, or both), but any relationship between this heterogeneity and underlying pathology remains elusive. In this study we demonstrate that physiological delta-frequency rhythms act as an effective substrate to permit modeling of SpW of cortical origin and may help to address this issue. For a starting point of delta activity, multiple subtypes of SpW could be modeled computationally and experimentally by either enhancing the magnitude of excitatory synaptic events ascending from neocortical layer 5 to layers 2/3 or selectively modifying superficial layer GABAergic inhibition. The former generated SpW containing multiple field spikes with long interspike intervals, whereas the latter generated SpW with short-interval multiple field spikes. Both types had different laminar origins and each disrupted interlaminar cortical dynamics in a different manner. A small number of examples of human recordings from patients with different diagnoses revealed SpW subtypes with the same temporal signatures, suggesting that detailed quantification of the pattern of spikes in SpW discharges may be a useful indicator of disparate underlying epileptogenic pathologies. NEW & NOTEWORTHY Spike-and-wave-type discharges (SpW) are a common feature in many epilepsies. Their electrographic manifestation is highly varied, as are available genetic clues to associated underlying pathology. Using computational and in vitro models, we demonstrate that distinct subtypes of SpW are generated by lamina-selective disinhibition or enhanced interlaminar excitation. These subtypes could be detected in at least some noninvasive patient recordings, suggesting more detailed analysis of SpW may be useful in determining clinical pathology.
Collapse
Affiliation(s)
- Stephen P Hall
- Hull York Medical School, University of York , Heslington , United Kingdom
| | - Roger D Traub
- Department of Physical Sciences, IBM Thomas J. Watson Research Center , Yorktown Heights, New York
| | - Natalie E Adams
- Hull York Medical School, University of York , Heslington , United Kingdom
| | - Mark O Cunningham
- Institute of Neuroscience, Newcastle University , Newcastle upon Tyne , United Kingdom
| | - Ian Schofield
- Department of Clinical Neurophysiology, Royal Victoria Infirmary, Newcastle upon Tyne , United Kingdom
| | - Alistair J Jenkins
- Department of Clinical Neurophysiology, Royal Victoria Infirmary, Newcastle upon Tyne , United Kingdom
| | | |
Collapse
|
14
|
Maksimenko VA, Lüttjohann A, Makarov VV, Goremyko MV, Koronovskii AA, Nedaivozov V, Runnova AE, van Luijtelaar G, Hramov AE, Boccaletti S. Macroscopic and microscopic spectral properties of brain networks during local and global synchronization. Phys Rev E 2017; 96:012316. [PMID: 29347072 DOI: 10.1103/physreve.96.012316] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Indexed: 11/07/2022]
Abstract
We introduce a practical and computationally not demanding technique for inferring interactions at various microscopic levels between the units of a network from the measurements and the processing of macroscopic signals. Starting from a network model of Kuramoto phase oscillators, which evolve adaptively according to homophilic and homeostatic adaptive principles, we give evidence that the increase of synchronization within groups of nodes (and the corresponding formation of synchronous clusters) causes also the defragmentation of the wavelet energy spectrum of the macroscopic signal. Our methodology is then applied to getting a glance into the microscopic interactions occurring in a neurophysiological system, namely, in the thalamocortical neural network of an epileptic brain of a rat, where the group electrical activity is registered by means of multichannel EEG. We demonstrate that it is possible to infer the degree of interaction between the interconnected regions of the brain during different types of brain activities and to estimate the regions' participation in the generation of the different levels of consciousness.
Collapse
Affiliation(s)
- Vladimir A Maksimenko
- Yuri Gagarin State Technical University of Saratov, REC "Nonlinear Dynamics of Complex Systems," Saratov 410054, Russia
| | - Annika Lüttjohann
- University of Münster, Institute of Physiology I, Münster 48149, Germany
| | - Vladimir V Makarov
- Yuri Gagarin State Technical University of Saratov, REC "Nonlinear Dynamics of Complex Systems," Saratov 410054, Russia
| | - Mikhail V Goremyko
- Yuri Gagarin State Technical University of Saratov, REC "Nonlinear Dynamics of Complex Systems," Saratov 410054, Russia
| | - Alexey A Koronovskii
- Saratov State University, Faculty of Nonlinear Processes, Saratov 410012, Russia
| | - Vladimir Nedaivozov
- Yuri Gagarin State Technical University of Saratov, REC "Nonlinear Dynamics of Complex Systems," Saratov 410054, Russia
| | - Anastasia E Runnova
- Yuri Gagarin State Technical University of Saratov, REC "Nonlinear Dynamics of Complex Systems," Saratov 410054, Russia
| | | | - Alexander E Hramov
- Yuri Gagarin State Technical University of Saratov, REC "Nonlinear Dynamics of Complex Systems," Saratov 410054, Russia
| | - Stefano Boccaletti
- CNR-Institute for complex systems, Sesto Fiorentino 50019, Italy.,The Italian Embassy in Tel Aviv, Tel Aviv 68125, Israel
| |
Collapse
|
15
|
Russo E, Citraro R, Constanti A, Leo A, Lüttjohann A, van Luijtelaar G, De Sarro G. Upholding WAG/Rij rats as a model of absence epileptogenesis: Hidden mechanisms and a new theory on seizure development. Neurosci Biobehav Rev 2016; 71:388-408. [DOI: 10.1016/j.neubiorev.2016.09.017] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Revised: 09/19/2016] [Indexed: 02/06/2023]
|