Dynamic Transitions of Epilepsy Waveforms Induced by Astrocyte Dysfunction and Electrical Stimulation

Zhang, Honghui; Shen, Zhuan; Zhao, Qiangui; Yan, Liang; Du, Lin; Deng, Zichen

doi:10.1155/2020/8867509

Cited by 9 publications

(5 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This increase in frequency and amplitude can be used effectively for seizure prediction and abatement. Some recent studies [51,52] have explored in the thalamocortical circuitry the effect of pyramidal neurons and inhibitory neurons in seizure generation and propagation but they didn't investigate the role that excitatory interneurons can play in epileptic seizures. However, according to the bifurcation analysis of our model, excitatory interneurons has an important role in the transition from interictal to generalized seizures.…”

Section: Discussionmentioning

confidence: 99%

The critical modulatory role of spiny stellate cells in seizure onset based on dynamic analysis of a neural mass model

Tabatabaee

Bahrami

Janahmadi

2021

Preprint

View full text Add to dashboard Cite

Increasing evidence has shown that excitatory neurons in the brain play a significant role in seizure generation. However, spiny stellate cells are cortical excitatory non-pyramidal neurons in the brain which their basic role in seizure occurrence is not well understood. In the present research, we study the critical role of spiny stellate cells or the excitatory interneurons (EI), for the first time, in epileptic seizure generation using an extended neural mass model introduced originally by Taylor and colleagues in 2014. Applying bifurcation analysis on this modified model, we investigated the rich dynamics corresponding to the epileptic seizure onset and transition between interictal and ictal states due to the EI. Our results indicate that the transition is described by a supercritical Hopf bifurcation which shapes the preictal activity in the model and suggests why before seizure onset, the amplitude and frequency of neural activities increase gradually. Moreover, we showed that 1) the altered function of GABAergic and glutamatergic receptors of EI can cause seizure, and 2) the pathway between the thalamic relay nucleus and EI facilitates the transition from interictal to the ictal activity by decreasing the preictal period. Thereafter, we considered both sensory and cortical periodic inputs to drive the model responses to various harmonic stimulations. Our results from the bifurcation analysis of the model suggest that the initial stage of the brain might be the main cause for the transition between interictal and ictal states as the stimulus frequency changes. The extended thalamocortical model shows also that the amplitude jump phenomenon and nonlinear resonance behavior result from the preictal stage of the brain. These results can be considered as a step forward to a deeper understanding of the mechanisms underlying the transition from brain normal activities to epileptic activities.

show abstract

Section: Discussionmentioning

confidence: 99%

The critical modulatory role of spiny stellate cells in seizure onset based on dynamic analysis of a neural mass model

Tabatabaee

Bahrami

Janahmadi

2021

Preprint

View full text Add to dashboard Cite

show abstract

“…Astrocyte dysfunction has been implicated in the pathophysiology of epilepsy [66][67][68][69], post-traumatic aberrant neurogenesis [70,71], and interneuron degeneration [72]. To gain insight into the molecular pathways associated with astrocyte dysfunction in PTE, we performed RNA-Seq on astrocytes isolated from the ipsilateral and contralateral hippocampus of sham, PTE + , and PTE − mice at 4 months following CCI injury.…”

Section: Transcriptomic Signature Of Forebrain Pte + Astrocytes Follo...mentioning

confidence: 99%

Atypical Neurogenesis, Astrogliosis, and Excessive Hilar Interneuron Loss Are Associated with the Development of Post-Traumatic Epilepsy

Basso

Shandra

Volanth

et al. 2023

Cells

View full text Add to dashboard Cite

Background: Traumatic brain injury (TBI) remains a significant risk factor for post-traumatic epilepsy (PTE). The pathophysiological mechanisms underlying the injury-induced epileptogenesis are under investigation. The dentate gyrus—a structure that is highly susceptible to injury—has been implicated in the evolution of seizure development. Methods: Utilizing the murine unilateral focal control cortical impact (CCI) injury, we evaluated seizure onset using 24/7 EEG video analysis at 2–4 months post-injury. Cellular changes in the dentate gyrus and hilus of the hippocampus were quantified by unbiased stereology and Imaris image analysis to evaluate Prox1-positive cell migration, astrocyte branching, and morphology, as well as neuronal loss at four months post-injury. Isolation of region-specific astrocytes and RNA-Seq were performed to determine differential gene expression in animals that developed post-traumatic epilepsy (PTE+) vs. those animals that did not (PTE−), which may be associated with epileptogenesis. Results: CCI injury resulted in 37% PTE incidence, which increased with injury severity and hippocampal damage. Histological assessments uncovered a significant loss of hilar interneurons that coincided with aberrant migration of Prox1-positive granule cells and reduced astroglial branching in PTE+ compared to PTE- mice. We uniquely identified Cst3 as a PTE+-specific gene signature in astrocytes across all brain regions, which showed increased astroglial expression in the PTE+ hilus. Conclusions: These findings suggest that epileptogenesis may emerge following TBI due to distinct aberrant cellular remodeling events and key molecular changes in the dentate gyrus of the hippocampus.

show abstract

“…Astrocyte dysfunction has been implicated in the pathophysiology of epilepsy [64][65][66][67], post-traumatic aberrant neurogenesis [68,69], and interneuron degeneration [70]. To gain insight into the molecular pathways associated with astrocyte dysfunction in PTE, we performed RNA-seq on astrocytes isolated from the ipsilateral and contralateral hippocampus of sham, PTE + and PTEmice at 4 months post-CCI injury.…”

Section: Transcriptomic Signature Of Forebrain Pte + Astrocytes Follo...mentioning

confidence: 99%

Atypical Neurogenesis, Astrogliosis, and Excessive Hilar Interneuron Loss Are Associated With the Development of Post-Traumatic Epilepsy

Basso¹,

Shandra²,

Volanth³

et al. 2023

Preprint

View full text Add to dashboard Cite

Background: Traumatic brain injury (TBI) remains a significant risk factor for post-traumatic epilepsy (PTE). The pathophysiological mechanisms underlying the injury-induced epileptogenesis are under under investigation. The dentate gyrus, a structure highly susceptible to injury, and has been implicated in the evolution of seizure development. Methods: Utilizing the murine unilateral focal control cortical impact (CCI) injury, we evaluated seizure onset using 24/7 EEG video analysis at 2-4 months post-injury. Cellular changes in the dentate gyrus and hilus of the hippocampus were quantified by non-biased stereology and Imaris image analysis to evaluate Prox1-positive cell migration, astrocyte branching and morphology, as well as neuronal loss at four months post-injury. Isolation of region-specific astrocytes and RNA-seq was performed to determine differential gene expression in PTE+ vs. PTE- that may comport with the epileptogenic process. Results: CCI injury resulted in 37% PTE+-incidence, which increased with injury severity and hippocampal damage. Histological assessments uncovered a significant loss of hilar interneurons that coincided with aberrant migration of Prox1-positive granule cells and reduced astroglial branching in PTE+ compared to PTE- mice. We uniquely identified Cst3 as a PTE+-specific gene signature in astrocytes across all brain regions. Conclusions: These findings suggest that epileptogenesis may emerge following TBI due to distinct aberrant cellular remodeling events and key molecular changes in the dentate gyrus of the hippocampus.

show abstract

Dynamic Transitions of Epilepsy Waveforms Induced by Astrocyte Dysfunction and Electrical Stimulation

Cited by 9 publications

References 65 publications

The critical modulatory role of spiny stellate cells in seizure onset based on dynamic analysis of a neural mass model

The critical modulatory role of spiny stellate cells in seizure onset based on dynamic analysis of a neural mass model

Atypical Neurogenesis, Astrogliosis, and Excessive Hilar Interneuron Loss Are Associated with the Development of Post-Traumatic Epilepsy

Atypical Neurogenesis, Astrogliosis, and Excessive Hilar Interneuron Loss Are Associated With the Development of Post-Traumatic Epilepsy

Contact Info

Product

Resources

About