The role of inflammation in epileptogenesis

Potential of Khaya senegalensis to mitigate epileptogenesis and cognitive dysfunction on kainate-induced post-status epilepticus model

Background and aim

To date, there is no treatment to prevent the development of temporal lobe epilepsy, the most common form of drug-resistant epilepsy. A recent study revealed the antiepileptic-like effect of the aqueous extract of Khaya senegalensis. Given the potential of this extract, the antiepileptogenic- and learning and memory-facilitating-like effects of the aqueous extract of Khaya senegalensis were assessed using the kainate-induced post-status epilepticus model.

Methods

Epilepsy was induced by injecting a single dose of kainate (12 mg/kg, i.p.) in rats. Animals that developed 2 hours of status-epilepticus were randomized and treated as follows: a negative control group received distilled water (10 ml/kg, p.o.); two positive control groups received sodium valproate (300 mg/kg, p.o.) or phenobarbital (20 mg/kg, p.o.); and three test groups received the extract (50, 100, 200 mg/kg, p.o.). A sham group was added and received distilled water (10 ml/kg, p.o.). All treatments were performed twice daily until the occurrence of the first spontaneous seizure (stage 4 or 5) in the negative control group, on day 14. After the completion of treatments, memory impairment was assessed using the T-maze. Two weeks following behavioral analysis, the rats that received the most effective dose of the extract on spontaneous recurrent were challenged with pentylenetetrazole (30 mg/kg, i.p.). This is to assess their susceptibility to generalized tonic-clonic seizures (stage 5). Rats were finally euthanized, and pro-inflammatory cytokines, or neurogenesis markers were quantified in the hippocampus.

Results

The extract of Khaya senegalensis significantly prevented spontaneous recurrent seizures on day 14. It also reduced cognitive decline. Furthermore, it significantly decreased pro-inflammatory cytokines levels and increased those of neurotrophic factors.

Conclusions

These findings thus suggest that the extract is endowed with antiepileptogenic- and learning and memory-enhancing-like effects. These effects are likely mediated by anti-inflammatory and neurotrophic pathways. This justifies, therefore, its use to treat empirically epilepsy.

Preclinical PET imaging in epileptogenesis: towards identification of biomarkers and therapeutic targets

BACKGROUND

Epilepsy is a neurological disorder that affects a significant portion of the global population. However, its complexity and the lack of biomarkers hinder the study of its etiology, resulting in a lack of effective treatments to slow down or halt disease development, also called epileptogenesis.

MAIN BODY

Animal models have proven to be a crucial tool for studying epileptogenesis, many exhibiting cellular, molecular, and functional alterations that resemble those found in human patients. This review examines preclinical studies that have utilized positron emission tomography, a non-invasive neuroimaging technique that has demonstrated correlation with the pathological features and behavioral comorbidities of the disease and a high predictive value for the severity of epileptogenesis.

CONCLUSION

Positron emission tomography imaging has fostered the knowledge of the mechanisms driving epileptogenesis. This translational technique might be crucial for identifying biomarkers of epilepsy, identifying novel treatment targets and selecting and monitoring patients for potential future therapies.

Cynarin protects against seizures and neuronal death in a rat model of kainic acid-induced seizures

The potential therapeutic value of cynarin, a phenolic compound derived from artichoke, in treating epilepsy has not yet been reported. The present study evaluated the effects of cynarin on a kainic acid (KA)-induced seizure rat model and its potential mechanism. Cynarin was administered through oral gavage at a dosage of 10 mg kg-1 daily for 7 days before the induction of seizures with KA (15 mg kg-1) via intraperitoneal injection. The results showed that pretreatment with cynarin effectively attenuated the KA-induced seizure score and electroencephalogram (EEG) changes and prevented neuronal loss and glial cell activation in the hippocampi of KA-treated rats. In addition, pretreatment with cynarin dramatically prevented the aberrant levels of high mobility group box 1 (HMGB1), toll-like receptor-4 (TLR4), p-IκB, p65-NFκB, interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor (TNF-α) induced by KA administration in hippocampal tissues. Additionally, KA substantially increased hippocampal glutamate levels and decreased cerebral blood flow, which were significantly alleviated by pretreatment with cynarin. The observed effects of cynarin were comparable to those of the antiepileptic drug carbamazepine (CBZ). Furthermore, there was no significant difference in the serum AST, ALT, creatinine, or bilirubin levels between the cynarin-treated rats and the control rats. Cynarin has a neuroprotective effect on a rat model of seizures induced by KA, reducing seizures, gliosis, inflammatory cytokines, and glutamate elevation and increasing cerebral blood flow. Thus, cynarin has therapeutic potential for preventing epilepsy.

Dapagliflozin alleviated seizures and cognition impairment in pilocarpine induced status epilepticus via suppressing microglia-mediated neuroinflammation and oxidative stress

BACKGROUND

Status epilepticus (SE) is a neurological emergency with prolonged seizures leading to chronic epilepsy, cognitive impairment, and neuronal damage. Microglial activation, subsequent neuroinflammation and oxidative stress contribute to SE-induced neuronal injury. Single-cell sequencing has delineated the pro-inflammatory microenvironment in epileptic lesions, characterized by widespread microglial activation. Dapagliflozin, an inhibitor of sodium-glucose cotransporter 2 (SGLT2), has shown potential in modulating neuroinflammatory responses. This study aimed to investigate the effects of Dapagliflozin on seizure and cognitive impairment by alleviating microglia-mediated neuroinflammation, oxidative stress.

METHODS

Single-Cell Transcriptomic Analysis were used to reveal SLC5A2 cellular heterogeneity and subtype-specific signatures of Temporal lobe Epilepsy. Male C57BL/6 mice were administered pilocarpine. Dapagliflozin were injected immediately after the termination of SE and at 24-hour intervals after SE until sacrifice. The latency and seizure score were recorded. Morris water maze were used to evaluate cognitive function of mouse. The neuroinflammation cell model was induced by lipopolysaccharide(LPS) in BV2 cell. Immunofluorescent staining, immunohistochemistry, flow cytometry, western blot, RT-qPCR, ELISA etc were used to examine the activation of microglia, evaluate neuroinflammation and oxidative stress.

RESULTS

The expression of SLC5A2 is up-regulated in microglia of epileptic patients. Administration of Dapagliflozin significantly reduced seizure activity and improved cognitive performance in SE mouse. Dapagliflozin reduced microglial activation, as indicated by downregulation of CD86, iNOS expression and increased CD206, Arg-1 level. Dapagliflozin decreased oxidative stress, as evidenced by reduced levels of malondialdehyde (MDA), reactive oxygen species (ROS), increased superoxide dismutase (SOD) and Glutathione (GSH) activity. In addition, Dapagliflozin treatment can rescured the neuronal damage and suppressed the release of inflammatory cytokines such as IL-6, IL-18 and IL-1β.

CONCLUSION

Our findings suggest that Dapagliflozin exerts neuroprotective effects by modulating microglia-mediated neuroinflammation and oxidative stress. The inhibition of SGLT2 may represent a novel therapeutic strategy for the treatment of SE and associated cognitive impairments.

Hydrogen inhalation exerts anti-seizure effects by preventing oxidative stress and inflammation in the hippocampus in a rat model of kainic acid-induced seizures

Hydrogen gas (H2) is an antioxidant with demonstrated neuroprotective efficacy. In this study, we administered H2 via inhalation to rats to evaluate its effects on seizures induced by kainic acid (KA) injection and the underlying mechanism. The animals were intraperitoneally injected with KA (15 mg/kg) to induce seizures. H2 was inhaled 2 h once a day for 5 days before KA administration. The seizure activity was evaluated using Racine's convulsion scale and electroencephalography (EEG). Neuronal cell loss, glial cell activation, and the levels of inflammatory cytokines (TNF-α, IL-1β, IL-6, CCL2, and CCL3), reactive oxygen species (ROS) and nuclear factor erythroid 2-related factor 2 (Nrf2) in the hippocampus were assessed. The cerebral blood flow of the rats was also evaluated. The results revealed that KA-treated rats presented increased seizure intensity; increased neuronal loss and astrocyte activation; increased levels of ROS, TNF-α, IL-1β, IL-6, CCL2, and CCL3; and reduced Nrf2 phosphorylation levels. Pretreatment with H2 inhalation significantly attenuated seizure intensity; prevented neuronal loss; decreased microglial and astrocytic activation; decreased ROS, TNF-α, IL-1β, IL-6, CCL2 and CCL3 levels; and increased Nrf2 levels. Inhalation of H2 also prevented the KA-induced decrease in cerebral blood flow. These results suggest that pretreatment with H2 inhalation ameliorates KA-induced seizures and inhibits the inflammatory response and oxidative stress, which protects neurons.

Risk factors of posthemorrhagic seizure in spontaneous intracerebral hemorrhage

Seizure is a relatively common neurological consequence after spontaneous intracerebral hemorrhage (SICH). This study aimed to investigate risk factors of early, late, and overall seizures in patients with SICH. Retrospective analysis was performed on all patients with SICH who completed two years of follow-up. The variables collected were obtained from demographic, clinical, radiographic and treatment data, in-hospital complications, and follow-up results. Univariate and multivariate analyzes were used to identify risk factors for post-hemorrhagic stroke seizure. Of 400 SICH patients recruited, 30 (7.5%) and 40 (10%) developed early and late seizures during the 2-year follow-up period, respectively. In the final result of the multivariate analysis, factors associated with the occurrence of the early seizure included lobar location of hematoma (p = 0.018), and GCS ≤ 12 on initial clinical presentation (p = 0.007). Factors associated with the occurrence of the late seizure included lobar location of hematoma (p = 0.001), volume of hematoma greater than 10 ml (p = 0.009), and midline shift on initial cranial CT (p = 0.036). Risk factors of the overall seizure after SICH included lobar location of hematoma (p < 0.001), volume of hematoma greater than 10 ml (p < 0.001), and craniotomy with evacuation of hematoma (p = 0.007). Furthermore, seizure was also associated with a poor functional outcome 2 years after the onset of SICH. Several factors associated with the appearance of post-ICH seizures were revealed. In patients with increased risk of post-SICH seizures, appropriate surveillance and management of seizures should be carried out.

From Gut Microbiomes to Infectious Pathogens: Neurological Disease Game Changers

Gut microbiota and infectious diseases affect neurological disorders, brain development, and function. Compounds generated in the gastrointestinal system by gut microbiota and infectious pathogens may mediate gut-brain interactions, which may circulate throughout the body and spread to numerous organs, including the brain. Studies shown that gut bacteria and disease-causing organisms may pass molecular signals to the brain, affecting neurological function, neurodevelopment, and neurodegenerative diseases. This article discusses microorganism-producing metabolites with neuromodulator activity, signaling routes from microbial flora to the brain, and the potential direct effects of gut bacteria and infectious pathogens on brain cells. The review also considered the neurological aspects of infectious diseases. The infectious diseases affecting neurological functions and the disease modifications have been discussed thoroughly. Recent discoveries and unique insights in this perspective need further validation. Research on the complex molecular interactions between gut bacteria, infectious pathogens, and the CNS provides valuable insights into the pathogenesis of neurodegenerative, behavioral, and psychiatric illnesses. This study may provide insights into advanced drug discovery processes for neurological disorders by considering the influence of microbial communities inside the human body.

Neuroprotective effect of naringin by modulation of klotho and HMGB1- TLR4 axis in PTZ-induced kindling in mice

BACKGROUND

Naringin has demonstrated various neuroprotective effects; however, its anti-inflammatory and cognitive properties, particularly through the regulation of HMGB1-TLR4 and Klotho, have not been explored in the context of epilepsy.

METHOD

Kindling was induced in Swiss albino mice by administering pentylenetetrazole (PTZ) 25 mg/kg intraperitoneally (i.p.). Naringin (40 mg/kg and 80 mg/kg) was administered orally for 6 weeks. The severity of seizures was assessed using the Racine scale. Cognitive function was evaluated by measuring step-down latency and transfer latency. The levels of GABA, glutamate, IL-1β, IL-1R1, IL-6, HMGB1, TLR4, TNF-α, Klotho, and ADAM-10 were quantified using enzyme-linked immunosorbent assay (ELISA) techniques.

RESULTS

Naringin significantly attenuated PTZ-induced seizures at both doses (p < 0.01 for 40 mg/kg; p < 0.0001 for 80 mg/kg) compared to the PTZ group. Additionally, it enhanced retention latency in both step-down latency (p < 0.01 for 40 mg/kg; p < 0.0001 for 80 mg/kg) and transfer latency (p < 0.05 for both doses) compared to the PTZ group. Furthermore, it increased Klotho and ADAM-10 levels in both the hippocampus and cortex (p < 0.01 for 40 mg/kg; p < 0.001 for 80 mg/kg, respectively). Levels of HMGB1, TLR4, and pro-inflammatory cytokines were significantly decreased in both the hippocampus and cortex compared to the PTZ group.

CONCLUSION

Naringin exhibited anti-epileptic effects by regulating neurotransmitter levels and preventing PTZ-induced kindling. Additionally, it demonstrated neuroprotective effects on cognition and attenuated neuroinflammation. These findings suggest that naringin may be a potential therapeutic agent for epilepsy-associated cognitive dysfunction, warranting further studies for clinical translation.

Cytotoxicity and Immunomodulatory Effects of Cannabidiol on Canine PBMCs: A Study in LPS-Stimulated and Epileptic Dogs

Cannabidiol, the primary non-psychoactive phytocannabinoid found in cannabis, has generated significant research interest due to its potential for biological effects, such as anti-inflammatory, analgesic, immunomodulatory, and anticonvulsant properties. Several studies have demonstrated the potential of CBD to alter inflammatory cytokines; however, data on CBD's effects on cell viability and pro-inflammatory cytokines in target animals, such as dogs, are limited. Therefore, in this study, we investigated the effects of CBD on the cell viability and modulation of pro-inflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α), in canine PBMCs stimulated with LPS. To evaluate the effect of CBD on neuroinflammation in epilepsy pathology, an independent study of five refractory epileptic dogs co-treated with CBD for 30 days was conducted. The current findings revealed that CBD concentrations of 16 µg/mL had a statistically significant effect on the viability of canine PBMCs with a calculated IC50 of 15.54 µg/mL. The effect of CBD on inflammatory cytokines in LPS-stimulated PBMCs tended to be dose-dependent, with CBD concentrations of 5-30 μg/mL resulting in decreased production of the tested pro-inflammatory cytokines. Considering the effect of CBD on cytokine production by PBMCs from epileptic dogs, CBD has the potential to modulate immune responses and provide benefits when used in combination with antiepileptic drugs. The findings provided evidence of CBD cytotoxicity and its effect on the alteration of pro-inflammatory cytokines in canine PBMCs.

PET imaging identifies anti-inflammatory effects of fluoxetine and a correlation of glucose metabolism during epileptogenesis with chronic seizure frequency

The serotonergic system has shown to be altered during epileptogenesis and in chronic epilepsy, making selective serotonin reuptake inhibitors interesting candidates for antiepileptogenic therapy. In this study, we aimed to evaluate disease-modifying effects of fluoxetine during experimental epileptogenesis. Status epilepticus (SE) was induced by lithium-pilocarpine, and female rats were treated either with vehicle or fluoxetine over 15 days. Animals were subjected to 18F-FDG (7 days post-SE), 18F-GE180 (15 days post-SE) and 18F-flumazenil positron emission tomography (PET, 21 days post-SE). Uptake (18F-FDG), volume of distribution (18F-GE180) and binding potential (18F-flumazenil) were calculated. In addition, hyperexcitability testing and video-EEG monitoring were performed. Fluoxetine treatment did not alter brain glucose metabolism. 18F-GE180 PET indicated lower neuroinflammation in the hippocampus of treated animals (-22.6%, p = 0.042), but no differences were found in GABAA receptor density. Video-EEG monitoring did not reveal a treatment effect on seizure frequency. However, independently of the treatment, hippocampal FDG uptake 7 days after SE correlated with seizure frequency during the chronic phase (r = -0.58; p = 0.015). Fluoxetine treatment exerted anti-inflammatory effects in rats during epileptogenesis. However, this effect did not alter disease outcome. Importantly, FDG-PET in early epileptogenesis showed biomarker potential as higher glucose metabolism correlated to lower seizure frequency in the chronic phase.

Geraniol Ameliorates Pentylenetetrazol-Induced Epilepsy, Neuroinflammation, and Oxidative Stress via Modulating the GABAergic Tract: In vitro and in vivo studies

Introduction

Geraniol (Ger), a monoterpene, is a common constituent of several essential oils. This study explored the anticonvulsant effect of Ger in-vitro using nerve growth factor (NGF) prompted PC12 cell injured by Glutamate (Glu) and in-vivo using Pentylenetetrazole (PTZ)-induced kindling through the GABAergic pathway.

Materials

To assess the effect of Ger on NGF prompted PC12 cells injured by Glu, Ger at concentrations of 25, 50, 100, 200 and 400 μg/mL was used. GABA, 5-HT, IL-1β, IL-4, and TNF-α levels and the gene expressions of GABAA-Rα1, NMDAR1, GAD 65, GAD 67, GAT 1 and GAT 3 were measured in NGF-induced PC12 cells treated with Ger (100, and 200 μg/mL). Mice were randomly separated into five groups. Normal and PTZ groups in which mice were injected with saline or PTZ, respectively. PTZ + Ger 100, PTZ + Ger 200 and PTZ + SV groups in which mice orally administered Ger or sodium valproate (SV), respectively, then injected with PTZ.

Results

Ger up to 400 μg/mL did not display any toxicity or injury in PC12 cells. Ger (100 to 200 μg/mL) reduced the injury induced by Glu, increased the gene expression of GABAA-Rα1, GAD65 and GAD67 and decreased GAT 1, GAT 3 and NMDAR1 expression in NGF-induced PC12 cells damaged by Glu. Ger (100 to 200 μg/mL) increased GABA and reduced TNF-α, IL-4 and IL-1β levels in NGF-induced PC12 cells injured by Glu. As for the in-vivo results, Ger increased GABA, GAD, GAT 1 and 3 and lowered GABA T. Ger mitigated MDA, NO, IL-1β, IL-6, TNF-α and IFN-γ, GFAP, caspase-3, and -9 levels and Bax gene expression and escalated GSH, SOD, catalase, BDNF and Bcl2 gene expression.

Conclusion

Ger reduced the oxidative stress status, neuroinflammation and apoptosis and activated GABAergic neurotransmission, which might clarify its anticonvulsant. Ger protects animals against PTZ prompted kindling as established by the enhancement in short term as well as long-term memory. Ger mitigated the injury induced by Glu in NGF prompted PC12 cell.

S100A4 promotes experimental autoimmune encephalomyelitis by impacting microglial inflammation through TLR4/NF-κB signaling pathway

Multiple sclerosis (MS) is a neurodegenerating autoimmune disease with no clinical cure currently. The calcium-binding protein S100A4 has been demonstrated to exert regulatory roles in inflammatory disorders including MS. However, the precise mechanisms by which S100A4 regulates neuroinflammation in MS remains unknown. To investigate the regulatory effect of S100A4 on microglial inflammation and its impact on neuroinflammation, the mouse-derived microglia cell line BV2 cells were infected with lentivirus to knockout S100A4 for in vitro studies. Wild-type (WT) and S100A4-/- mice were induced to develop experimental autoimmune encephalomyelitis (EAE), an animal model of MS, for in vivo investigation. Results indicated that the frequencies of microglia in the spinal cord and brain and the expression of S100A4 in these tissues varied kinetically along with the progression of the disease in mice with EAE. S100A4-/- mice presented ameliorated clinical scores of EAE and exhibited less severe EAE signs, including inflammatory cell infiltration in the spinal cord and brain and demyelination of the spinal cord. Moreover, these mice demonstrated overall reduced levels of inflammatory cytokines in the spinal cord and brain. Compromised systematic inflammatory responses including circulating cytokines and frequencies of immune cells in the spleen were also observed in these mice. In addition, both exogenous and endogenous S100A4 could promote the microglial inflammation, affect the polarization of microglia and enhance inflamed microglia-mediated apoptosis of neuronal cells through TLR4/NF-κB signaling pathway. Thus, S100A4 may participate in the regulation of neuroinflammation at least partly through regulating the inflammation of microglia.

Presumed aetiologies and clinical outcomes of non-lesional late-onset epilepsy

BACKGROUND AND PURPOSE

Our objective was to define phenotypes of non-lesional late-onset epilepsy (NLLOE) depending on its presumed aetiology and to determine their seizure and cognitive outcomes at 12 months.

METHODS

In all, 146 newly diagnosed NLLOE patients, >50 years old, were prospectively included and categorized by four presumed aetiological subtypes: neurodegenerative subtype (patients with a diagnosis of neurodegenerative disease) (n = 31), microvascular subtype (patients with three or more cardiovascular risk factors and two or more vascular lesions on MRI) (n = 39), inflammatory subtype (patient meeting international criteria for encephalitis) (n = 9) and unlabelled subtype (all individuals who did not meet the criteria for other subtypes) (n = 67). Cognitive outcome was determined by comparing for each patient the proportion of preserved/altered scores between initial and second neuropsychological assessment.

RESULTS

The neurodegenerative subtype had the most severe cognitive profile at diagnosis with cognitive complaint dating back several years. The microvascular subtype was mainly evaluated through the neurovascular emergency pathway. Their seizures were characterized by transient phasic disorders. Inflammatory subtype patients were the youngest. They presented an acute epilepsy onset with high rate of focal status epilepticus. The unlabelled subtype presented fewer comorbidities with fewer lesions on brain imaging. The neurodegenerative subtype had the worst seizure and cognitive outcomes. In other groups, seizure control was good under antiseizure medication (94.7% seizure-free) and cognitive performance was stabilized or even improved.

CONCLUSION

This new characterization of NLLOE phenotypes raises questions regarding the current International League Against Epilepsy aetiological classification which does not individualize neurodegenerative and microvascular aetiology per se.

Inhibiting the soluble epoxide hydrolase increases the EpFAs and ERK1/2 expression in the hippocampus of LiCl-pilocarpine post-status epilepticus rat model

Purpose

This study aimed to investigate the enzyme activity of soluble epoxide hydrolase (sEH) and quantify its metabolic substrates, namely epoxygenated fatty acids (EpFAs), and products of sEH in the hippocampus after administering TPPU [1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl)urea], an inhibitor of sEH. Furthermore, it explored whether the extracellular signal-activated protein kinase 1/2 (ERK1/2) is involved in the anti-seizure effects of TPPU in the lithium chloride (LiCl)-pilocarpine induced post-status epilepticus (SE) rat model.

Methods

The rats were intraperitoneally (I.P.) injected with LiCl and pilocarpine to induce SE and then spontaneous recurrent seizures (SRS) were observed. Rats were randomly assigned into SRS + TPPU group (intragastrically administering 0.1 mg/kg/d TPPU), SRS + Vehicle group (administering the vehicle instead), and Control group. Enzyme-linked immunosorbent assay, Western-blot analysis, and ultra-high-performance liquid chromatography/mass spectrometry (LC/MS) were performed to measure the enzyme activity of sEH, the protein level of sEH and ERK1/2, and the concentration of TPPU and polyunsaturated fatty acids (PUFAs) metabolisms in the hippocampus.

Results

The frequency of SRS events of Racine stage 3 or higher ranged from 0 to 19 per week in the SRS + Vehicle group, compared to 0-5 per week in the SRS + TPPU group. sEH enzyme activity and protein levels were significantly elevated in the SRS + Vehicle group compared to the Control group. After TPPU administration, the hippocampal TPPU concentration reached 10.94 ± 4.37 nmol/kg. sEH enzyme activity was significantly reduced in the LiCl-pilocarpine-induced post-SE rat model, although sEH protein levels did not decrease significantly. The regioisomers 8,9-, 11,12-, and 14,15-EETs, total EETs, the EETs/DHETs ratio, other EpFAs including 16(17)-EpDPA, and the 19(20)-EpDPA/19,20-DiHDPA ratio in the hippocampus were significantly increased. Additionally, the p-ERK1/2 to ERK1/2 ratio in the hippocampus was significantly elevated following TPPU administration.

Conclusion

This study demonstrates that inhibiting sEH with TPPU increases the levels of EETs, other EpFAs, and ERK1/2 expression in the hippocampus of a LiCl-pilocarpine-induced post-SE rat model. These findings suggest that the anti-seizure effect of TPPU may be mediated through the EETs-ERK1/2 pathway.

WONOEP appraisal: The role of glial cells in focal malformations associated with early onset epilepsies

Epilepsy represents a common neurological disorder in patients with developmental brain lesions, particularly in association with malformations of cortical development and low-grade glioneuronal tumors. In these diseases, genetic and molecular alterations in neurons are increasingly discovered that can trigger abnormalities in the neuronal network, leading to higher neuronal excitability levels. However, the mechanisms underlying epilepsy cannot rely solely on assessing the neuronal component. Growing evidence has revealed the high degree of complexity underlying epileptogenic processes, in which glial cells emerge as potential modulators of neuronal activity. Understanding the role of glial cells in developmental brain lesions such as malformations of cortical development and low-grade glioneuronal tumors is crucial due to the high degree of pharmacoresistance characteristic of these lesions. This has prompted research to investigate the role of glial and immune cells in epileptiform activity to find new therapeutic targets that could be used as combinatorial drug therapy. In a special session of the XVI Workshop of the Neurobiology of Epilepsy (WONOEP, Talloires, France, July 2022) organized by the Neurobiology Commission of the International League Against Epilepsy, we discussed the evidence exploring the genetic and molecular mechanisms of glial cells and immune response and their implications in the pathogenesis of neurodevelopmental pathologies associated with early life epilepsies.

Disease modification upon brief exposure to tofacitinib during chronic epilepsy

All current drug treatments for epilepsy, a neurological disorder affecting over 50 million people( 1, 2 ) merely treat symptoms, and a third of patients do not respond to medication. There are no disease modifying treatments that may be administered briefly to patients to enduringly eliminate spontaneous seizures and reverse cognitive deficits( 3, 4 ). Applying network approaches to rodent models and human temporal lobectomy samples at both whole tissue and single-nuclei resolutions, we observe the well-characterized pattern of rapid induction and subsequent quenching exhibited of the JAK/STAT pathway within days of epileptogenic insult. This is followed by a resurgent activation weeks to months later with the onset of spontaneous seizures. Targeting the first wave of activation after epileptic insult does not prevent disease. However, brief inhibition of the second wave with CP690550 (Tofacitinib) ( 5, 6 ) enduringly suppresses seizures, rescues deficits in spatial memory, and alleviates epilepsy-associated histopathological alterations. Seizure suppression lasts for at least 2 months after the final dose. Using discovery-based transcriptomic analysis across models of epilepsy and validation of putative mechanisms with human data, we demonstrate a powerful approach to identifying disease modifying targets; this may be useful for other neurological disorders. With this approach, we find that reignition of inflammatory JAK/STAT3 signaling in chronic epilepsy opens a window for disease modification with the FDA-approved, orally available drug CP690550.

Human iPSC-derived microglia sense and dampen hyperexcitability of cortical neurons carrying the epilepsy-associated SCN2A-L1342P mutation

Neuronal hyperexcitability is a hallmark of epilepsy. It has been recently shown in rodent models of seizures that microglia, the brain's resident immune cells, can respond to and modulate neuronal excitability. However, how human microglia interact with human neurons to regulate hyperexcitability mediated by an epilepsy-causing genetic mutation found in patients is unknown. The SCN2A gene is responsible for encoding the voltage-gated sodium channel Nav1.2, one of the leading contributors to monogenic epilepsies. Previously, we demonstrated that the recurring Nav1.2-L1342P mutation leads to hyperexcitability in a male donor (KOLF2.1) hiPSC-derived cortical neuron model. Microglia originate from a different lineage (yolk sac) and are not naturally present in hiPSCs-derived neuronal cultures. To study how microglia respond to neurons carrying a disease-causing mutation and influence neuronal excitability, we established a co-culture model comprising hiPSC-derived neurons and microglia. We found that microglia display increased branch length and enhanced process-specific calcium signal when co-cultured with Nav1.2-L1342P neurons. Moreover, the presence of microglia significantly lowered the repetitive action potential firing and current density of sodium channels in neurons carrying the mutation. Additionally, we showed that co-culturing with microglia led to a reduction in sodium channel expression within the axon initial segment of Nav1.2-L1342P neurons. Furthermore, we demonstrated that Nav1.2-L1342P neurons release a higher amount of glutamate compared to control neurons. Our work thus reveals a critical role of human iPSCs-derived microglia in sensing and dampening hyperexcitability mediated by an epilepsy-causing mutation.Significance Statement Seizure studies in mouse models have highlighted the role of microglia in modulating neuronal activity, particularly in the promotion or suppression of seizures. However, a gap persists in comprehending the influence of human microglia on intrinsically hyperexcitable neurons carrying epilepsy-associated pathogenic mutations. This research addresses this gap by investigating human microglia and their impact on neuronal functions. Our findings demonstrate that microglia exhibit dynamic morphological alterations and calcium fluctuations in the presence of neurons carrying an epilepsy-associated SCN2A mutation. Furthermore, microglia suppressed the excitability of hyperexcitable neurons, suggesting a potential beneficial role. This study underscores the role of microglia in the regulation of abnormal neuronal activity, providing insights into therapeutic strategies for neurological conditions associated with hyperexcitability.

Enhancing glymphatic fluid transport by pan-adrenergic inhibition suppresses epileptogenesis in male mice

Epileptogenesis is the process whereby the previously normally functioning brain begins to generate spontaneous, unprovoked seizures. Status epilepticus (SE), which entails a massive release of neuronal glutamate and other neuroactive substances, is one of the best-known triggers of epileptogenesis. We here asked whether pharmacologically promoting glymphatic clearance during or after SE is beneficial and able to attenuate the subsequent epileptogenesis. We induced SE in adult male mice by intrahippocampal kainic acid (KA) infusion. Acute administration of a cocktail of adrenergic receptor antagonists (propranolol, prazosin, and atipamezole: PPA), enhanced glymphatic flow and effectively reduced the severity of spontaneous seizures in the chronic phase. The PPA treatment also reduced reactive gliosis and inhibited the loss of polarized expression of AQP4 water channels in the vascular endfeet of astrocytes. Administration of PPA after cessation of SE (30 hours post KA) also effectively suppressed epileptogenesis and improved outcome. Conversely, mice with constitutively low glymphatic transport due to genetic deletion of the aquaporin 4 (AQP4) water channel showed exacerbation of KA-induced epileptogenesis. We conclude that the pharmacological modulation of glymphatic fluid transport may represent a potential strategy to dampen epileptogenesis and the occurrence of spontaneous seizures following KA-induced SE.

Translocator protein (18 kDa) positron emission tomography imaging as a biomarker of neuroinflammation in epilepsy

Increasing evidence indicate that neuroinflammation triggered by glial cells plays a significant role in epileptogenesis. To this effect, the overexpression of translocator protein 18 kDa (TSPO) in activated microglia and astrocytes has been identified as an inflammatory biomarker in epilepsy. It is now possible to quantify neuroinflammation using non-invasive positron emission tomography (PET) imaging of TSPO. With the advancement of radiotracers, TSPO PET has become an innovative tool in elucidating the "neuroinflammatory machinery" of drug-resistant epilepsy. Furthermore, TSPO PET has demonstrated potential in detecting MRI-negative epileptogenic zones (EZ) and provided an innovative perspective in epileptic medical treatment. This manuscript presents a comprehensive exploration of the neuroinflammatory mechanisms of epilepsy, alongside a thorough review of TSPO PET studies conducted in clinical and preclinical settings. The primary objective is to deepen our understanding of epilepsy progression and to establish TSPO PET as an effective monitoring tool for treatment efficacy.

Riluzole attenuates acute neural injury and reactive gliosis, hippocampal-dependent cognitive impairments and spontaneous recurrent generalized seizures in a rat model of temporal lobe epilepsy

Background

Riluzole exhibits neuroprotective and therapeutic effects in several neurological disease models associated with excessive synaptic glutamate (Glu) release. We recently showed riluzole prevents acute excitotoxic hippocampal neural injury at 3 days in the kainic acid (KA) model of temporal lobe epilepsy (TLE). Currently, it is unknown if preventing acute neural injury and the neuroinflammatory response is sufficient to suppress epileptogenesis.

Methods

The KA rat model of TLE was used to determine if riluzole attenuates acute hippocampal neural injury and reactive gliosis. KA was administered to adult male Sprague-Dawley (250 g) rats at 5 mg/kg/hr until status epilepticus (SE) was observed, and riluzole was administered at 10 mg/kg 1 h and 4 h after SE and once per day for the next 2 days. Immunostaining was used to assess neural injury (FJC and NeuN), microglial activation (Iba1 and ED-1/CD68) and astrogliosis (GFAP and vimentin) at day 7 and day 14 after KA-induced SE. Learning and memory tests (Y-maze, Novel object recognition test, Barnes maze), behavioral hyperexcitability tests, and spontaneous generalized recurrent seizure (SRS) activity (24-hour video monitoring) were assessed at 11-15 weeks.

Results

Here we show that KA-induced hippocampal neural injury precedes the neuroimmune response and that riluzole attenuates acute neural injury, microglial activation, and astrogliosis at 7 and 14 days. We find that reducing acute hippocampal injury and the associated neuroimmune response following KA-induced SE by riluzole attenuates hippocampal-dependent cognitive impairment, behavioral hyperexcitability, and tonic/clonic generalized SRS activity after 3 months. We also show that riluzole attenuates SE-associated body weight loss during the first week after KA-induced SE.

Discussion

Riluzole acts on multiple targets that are involved to prevent excessive synaptic Glu transmission and excitotoxic neuronal injury. Attenuating KA-induced neural injury and subsequent microglia/astrocyte activation in the hippocampus and extralimbic regions with riluzole reduces TLE-associated cognitive deficits and generalized SRS and suggests that riluzole could be a potential antiepileptogenic drug.

Dexamethasone attenuates low-frequency brainwave disturbances following acute seizures induced by pentylenetetrazol in Wistar rats

Seizures are neurological disorders triggered by an imbalance in the activity of excitatory and inhibitory neurotransmitters in the brain. When triggered chronically, this imbalance can lead to epilepsy. Critically, many of the affected individuals are refractory to treatment. Given this, anti-inflammatory drugs, in particular glucocorticoids, have been considered as a potential antiepileptogenic therapy. Glucocorticoids are currently used in the treatment of refractory patients, although there have been contradictory results in terms of their use in association with antiepileptic drugs, which reinforces the need for a more thorough investigation of their effects. In this context, the present study evaluated the effects of dexamethasone (DEX, 0.6 mg/kg) on the electroencephalographic (EEG) and histopathological parameters of male Wistar rats submitted to acute seizure induced by pentylenetetrazol (PTZ). The EEG monitoring revealed that DEX reduced the total brainwave power, in comparison with PTZ, in 12 h after the convulsive episode, exerting this effect in up to 36 h (p < 0.05 for all comparisons). An increase in the accommodation of the oscillations of the delta, alpha, and gamma frequencies was also observed from the first 12 h onwards, with the accommodation of the theta frequency occurring after 36 h, and that of the beta frequency 24 h after the seizure. The histopathological analyses showed that the CA3 region and hilum of the hippocampus suffered cell loss after the PTZ-induced seizure (control vs. PTZ, p < 0.05), although DEX was not able to protect these regions against cell death (PTZ vs. DEX + PTZ, p > 0.05). While DEX did not reverse the cell damage caused by PTZ, the data indicate that DEX has beneficial properties in the EEG analysis, which makes it a promising candidate for the attenuation of the epileptiform wave patterns that can precipitate refractory seizures.

Ferroptosis and Pyroptosis in Epilepsy

Epilepsy is sudden, recurrent, and transient central nervous system dysfunction caused by abnormal discharge of neurons in the brain. Ferroptosis and pyroptosis are newly discovered ways of programmed cell death. One of the characteristics of ferroptosis is the oxidative stress generated by lipid peroxides. Similarly, pyroptosis has unique pro-inflammatory properties. As both oxidative stress and neuroinflammation are significant contributors to the pathogenesis of epilepsy, increasing evidence shows that ferroptosis and pyroptosis are closely related to epilepsy. This article reviews the current comprehension of ferroptosis and pyroptosis and elucidates potential mechanisms by which ferroptosis and pyroptosis may contribute to epilepsy. In addition, we also highlight the possible interactions between ferroptosis and pyroptosis because they reportedly coexist in many diseases, and increasing studies have demonstrated the convergence of pathways between the two. This is of great significance for explaining the occurrence and development of epilepsy and provides a new therapeutic perspective for the treatment of epilepsy.

The correlation of GluR3B antibody with T lymphocyte subsets and inflammatory factors and their role in the progression of epilepsy

OBJECTIVE

To investigate changes in proportions of peripheral blood lymphocyte subsets, the correlation between the lymphocyte subsets and cytokine levels in patients with GluR3B antibody-positive epilepsy, analyze the role of GluR3B antibodies and cytokines in the progression of epilepsy. In addition, the immunotherapeutic effect in patients with GluR3B antibody-positive epilepsy will be evaluated.

METHODS

Patients with epilepsy hospitalized in the Department of Neurology of the affiliated Hospital of Xuzhou Medical University from December 2016 to May 2023 were recruited. GluR3B antibody levels were measured by enzyme-linked immunosorbent assay (ELISA). Lymphocyte subset proportions were determined using flow cytometry, and serum concentrations of 12 cytokines were measured using cytometric beads array. Differences in T lymphocyte subsets and inflammatory factors were analysed between GluR3B antibody positive and negative patients. Structural equation modeling (SEM) was used to analyse the role of GluR3B antibodies and inflammatory factors in drug-resistant epilepsy (DRE). Finally, the therapeutic effect of immunotherapy on epilepsy patients with GluR3B antibodies was assessed.

RESULTS

In this study, sixty-four cases of DRE, sixty-six cases of drug-naïve epilepsy (DNE), and forty-one cases of drug-responsive epilepsy were recruited. (1) DRE patients with positive GluR3B antibody were characterized by a significant increase in the proportion of cluster of differentiation (CD)4+ T lymphocytes, a decrease in CD8+ T lymphocytes, and an increase of CD4+/CD8+ ratio. Similar alterations in T lymphocyte subsets were observed in GluR3B antibody-positive patients with DNE. GluR3B antibody levels correlated positively with CD4+ T lymphocytes (r = 0.23) and negatively with CD8+ T lymphocytes (r=-0.18). (2) In patients with DRE, the serum concentrations of interleukin-1β (IL-1β), IL-8, and interferon-gamma (IFN-γ) were significantly higher in those with positive GluR3B antibody compared to those with negative GluR3B antibody. Serum IL-1β levels were also higher in GluR3B antibody-positive DNE patients compared to antibody-negative DNE patients. In drug-responsive epilepsy patients with GluR3B antibody-positive, both serum IL-1β and IFN-γ levels were higher than those with GluR3B antibody-negative. Moreover, the concentrations of serum GluR3B antibody were positively correlated with the levels of IL-1β, IL-8, and IFN-γ. (3) SEM analysis indicated that GluR3B antibody may be a direct risk factor for DRE (direct effect = 4.479, 95%CI 0.409-8.503), or may be involved in DRE progression through affecting IFN-γ and IL-8 levels (total indirect effect = 5.101, 95%CI 1.756-8.818). (4) Immunotherapy significantly decreased seizure frequency and serum GluR3B antibody levels, and the seizure frequency was positively correlated with the levels of GluR3B antibody levels in patients receiving immunotherapy.

CONCLUSIONS

This study demonstrates that GluR3B antibody may influence the progression of epilepsy through altering the proportion of CD4+ and CD8+ lymphocyte subsets and increasing proinflammatory cytokines. The seizure suppression of immunotherapy is associated with the decrease of GluR3B antibody levels. Thus, the present study contributes to a better understanding of the immunoregulatory mechanisms of autoimmune-associated epilepsy and provides a potential target for DRE.

Biological significance and pathophysiological role of Matrix Metalloproteinases in the Central Nervous System

Matrix Metalloproteinases (MMPs), which are endopeptidase reliant on zinc, are low in embryonic tissues but increases in response to a variety of physiological stimulus and pathological stresses. Neuro-glial cells, endothelial cells, fibroblasts, and leucocytes secrete MMPs, which cleave extracellular matrix proteins in a time-dependent manner. MMPs affect synaptic plasticity and the development of short-term memory by controlling the size, shape, and excitatory synapses' function through the lateral diffusion of receptors. In addition, MMPs influence the Extracellular Matrix proteins in the Peri-Neuronal Net at the Neuro-glial interface, which aids in the establishment of long-term memory. Through modulating neuronal, and glial cells migration, differentiation, Neurogenesis, and survival, MMPs impact brain development in mammals. In adult brains, MMPs play a beneficial role in physiological plasticity, which includes learning, memory consolidation, social interaction, and complex behaviors, by proteolytically altering a wide variety of factors, including growth factors, cytokines, receptors, DNA repair enzymes, and matrix proteins. Additionally, stress, depression, addiction, hepatic encephalopathy, and stroke may all have negative effects on MMPs. In addition to their role in glioblastoma development, MMPs influence neurological diseases such as epilepsy, schizophrenia, autism spectrum disorder, brain damage, pain, neurodegeneration, and Alzheimer's and Parkinson's. To help shed light on the potential of MMPs as a therapeutic target for neurodegenerative diseases, this review summarizes their regulation, mode of action, and participation in brain physiological plasticity and pathological damage. Finally, by employing different MMP-based nanotools and inhibitors, MMPs may also be utilized to map the anatomical and functional connectome of the brain, analyze its secretome, and treat neurodegenerative illnesses.

Matrix metalloproteinase-9: A magic drug target in neuropsychiatry?

Neuropsychiatric conditions represent a major medical and societal challenge. The etiology of these conditions is very complex and combines genetic and environmental factors. The latter, for example, excessive maternal or early postnatal inflammation, as well as various forms of psychotrauma, often act as triggers leading to mental illness after a prolonged latent period (sometimes years). Matrix metalloproteinase-9 (MMP-9) is an extracellularly and extrasynaptic operating protease that is markedly activated in response to the aforementioned environmental insults. MMP-9 has also been shown to play a pivotal role in the plasticity of excitatory synapses, which, in its aberrant form, has repeatedly been implicated in the etiology of mental illness. In this conceptual review, we evaluate the experimental and clinical evidence supporting the claim that MMP-9 is uniquely positioned to be considered a drug target for ameliorating the adverse effects of environmental insults on the development of a variety of neuropsychiatric conditions, such as schizophrenia, bipolar disorder, major depression, autism spectrum disorders, addiction, and epilepsy. We also identify specific challenges and bottlenecks hampering the translation of knowledge on MMP-9 into new clinical treatments for the conditions above and suggest ways to overcome these barriers.

Causal relationship between immune cells and epilepsy mediated by metabolites analyzed through Mendelian randomization

Our study investigated the causal relationship between immune cells, metabolites, and epilepsy using two-sample Mendelian Randomization (MR) and mediation MR analysis of 731 immune cell traits and 1400 metabolites. Our core methodology centered on inverse-variance weighted MR, supplemented by other methods. This approach was crucial in clarifying the potential intermediary functions of metabolites in the genetic links between traits of immune cells and epilepsy. We found a causal relationship between immune cells and epilepsy. Specifically, the genetically predicted levels of CD64 on CD14-CD16- are positively correlated with the risk of epilepsy (p < 0.001, OR = 1.0826, 95% CI 1.0361-1.1312). Similarly, metabolites also exhibit a causal relationship with both immune cells (OR = 1.0438, 95% CI 1.0087-1.0801, p = 0.0140) and epilepsy (p = 0.0334, OR = 1.0897, 95% CI 1.0068-1.1795), and sensitivity analysis was conducted to further validate these relationships. Importantly, our intermediate MR results suggest that the metabolite Paraxanthine to linoleate (18:2n6) ratio may mediate the causal relationship between immune cell CD64 on CD14-CD16- and epilepsy, with a mediation effect of 5.05%. The results suggest the importance of specific immune cell levels and metabolites in understanding epilepsy's pathogenesis, which is significant for its prevention and treatment.

In Silico Screening Identification of Fatty Acids and Fatty Acid Derivatives with Antiseizure Activity: In Vitro and In Vivo Validation

High fat diets have been used as complementary treatments for seizure disorders for more than a century. Moreover, many fatty acids and derivatives, including the broad-spectrum antiseizure medication valproic acid, have been explored and used as pharmacological agents to treat epilepsy. In this work, we have explored the anticonvulsant potential of a large library of fatty acids and fatty acid derivatives, the LIPID MAPS Structure Database, using structure-based virtual screening to assess their ability to block the voltage-gated sodium channel 1.2 (NaV1.2), a validated target for antiseizure medications. Four of the resulting in silico hits were submitted for experimental confirmation using in vitro patch clamp experiments, and their protective role was evaluated in an acute mice seizure model, the Maximal Electroshock seizure model. These four compounds were found to protect mice against seizures. Two of them exhibited blocking effects on NaV1.2, CaV2.2, and CaV3.1.

Incidence of seizures in ICU patients with diffuse encephalopathy and its predictors

Encephalopathy is a diffuse brain dysfunction that results from systemic disorder. Patients with diffuse encephalopathy are at risk of developing clinical and electrographic seizures. The aim of this study is to assess the prevalence of electrographic seizures in a setting of encephalopathy and the clinical and electroencephalogram predictors. We retrospectively reviewed all continuous electroencephalograms done between 2019 and 2022. Continuous electroencephalograms with diffuse encephalopathy were included in the study. A total of 128 patients with diffuse encephalopathy were included in this study. Patients' ages ranged from 18 to 96 years old with a mean age of 55.3 ± 19.2 years old. Nine out of 128 patients had seizures with an incidence of 7%. Sixty-six point six percent were nonconvulsive electrographic seizures. Fourteen point three percent of the female patients with diffuse encephalopathy had seizures as compared to none of the male patients (P = .002). Also, 12% of patients with a history of epilepsy experienced seizures versus 5.8% of patients without this history (P = .049). Among electrographic features, 25% of patients with delta background had seizures versus 2.3% of the other patients (P = .048). Likewise, 90% of patients with periodic discharges developed seizures in comparison with none of the patients without (P = .001). Seizures are seen in 7% of patients with diffuse encephalopathy. Female gender, past history of epilepsy, delta background and periodic discharges are significant predictors of seizure development in patients with diffuse encephalopathy.

Futile recanalization is associated with increased risk of post-stroke epilepsy

BACKGROUND

Endovascular treatment (EVT) is the standard of care of ischaemic stroke due to occlusion of large vessels. Although EVT can significantly improve short- and long-term outcomes, functional dependence can persist despite the achievement of a successful recanalization. The evidence about the predictors of post-stroke epilepsy (PSE) in patients with stroke treated by EVT is limited. We aimed to evaluate the relationship between futile recanalization and the risk of PSE.

METHODS

We retrospectively identified consecutive adults with first-ever ischaemic stroke of anterior circulation who were treated with EVT. Futile recanalization was defined as poor 3-month functional status (modified Rankin scale score ≥ 3) despite complete or near-complete recanalization. Study outcome was the occurrence of PSE during the follow-up.

RESULTS

The study included 327 patients with anterior circulation ischaemic stroke treated with EVT. Futile recanalization occurred in 116 (35.5%) patients and 26 (8.0%) developed PSE during a median follow-up of 35 [interquartile range, 22.7-55.2] months. Futile recanalization was more common among patients who developed PSE compared to those who did not (76.9% versus 31.9%; p < 0.001). Futile recanalization [hazard ratio (HR) = 5.63, 95% confidence interval (CI): 1.88-16.84; p = 0.002], large artery atherosclerosis (HR = 3.48, 95% CI: 1.44-8.40; p = 0.006), cortical involvement (HR = 15.51, 95% CI: 2.06-116.98; p = 0.008), and acute symptomatic status epilepticus (HR = 14.40, 95% CI: 2.80-73.98; p = 0.001) increased the risk of PSE.

CONCLUSIONS

Futile recanalization after EVT is associated with increased risk of PSE in patients with ischaemic stroke due to occlusion of large vessel of the anterior circulation.

Incidence and predictors of posttraumatic epilepsy and cognitive impairment in patients with traumatic brain injury: A retrospective cohort study in Malaysia

OBJECTIVE

Posttraumatic epilepsy (PTE) significantly impacts morbidity and mortality, yet local PTE data remain scarce. In addition, there is a lack of evidence on cognitive comorbidity in individuals with PTE in the literature. We sought to identify potential PTE predictors and evaluate cognitive comorbidity in patients with PTE.

METHODS

A 2-year retrospective cohort study was employed, in which adults with a history of admission for traumatic brain injury (TBI) in 2019 and 2020 were contacted. Three hundred one individuals agreed to participate, with a median follow-up time of 30.75 months. The development of epilepsy was ascertained using a validated tool and confirmed by our neurologists during visits. Clinical psychologists assessed the patients' cognitive performance.

RESULTS

The 2-year cumulative incidence of PTE was 9.3% (95% confidence interval [CI] 5.9-12.7). The significant predictors of PTE were identified as a previous history of brain injury [hazard ratio [HR] 4.025, p = .021], and intraparenchymal hemorrhage (HR: 2.291, p = .036), after adjusting for other confounders. TBI patients with PTE performed significantly worse on the total ACE-III cognitive test (73.5 vs 87.0, p = .018), CTMT (27.5 vs 33.0, p = .044), and PSI (74.0 vs 86.0, p = .006) than TBI patients without PTE. A significantly higher percentage of individuals in the PTE group had cognitive impairment, compared to the non-PTE group based on ACE-III (53.6% vs 46.4%, p = .001) and PSI (70% vs 31.7%, p = .005) scores at 2 years post-TBI follow-up.

SIGNIFICANCE

This study emphasizes the link between TBI and PTE and the chance of developing cognitive impairment in the future. Clinicians can target interventions to prevent PTE by identifying specific predictors, which helps them make care decisions and develop therapies to improve patients' quality of life.

Understanding epileptogenesis from molecules to network alteration

Epilepsy is characterized by recurrent seizures. Following an initial insult, a latent period precedes the onset of spontaneous seizures, a process referred to as epileptogenesis. This period plays a critical role in halting the progression toward epilepsy before the onset of abnormal molecular and network alterations. In this study, the fundamental concepts of epileptogenesis as well as the associated molecular and cellular targets are reviewed.

Pharmacological elevation of glutathione inhibits status epilepticus-induced neuroinflammation and oxidative injury

Glutathione (GSH) is a major endogenous antioxidant, and its depletion has been observed in several brain diseases including epilepsy. Previous studies in our laboratory have shown that dimercaprol (DMP) can elevate GSH via post-translational activation of glutamate cysteine ligase (GCL), the rate limiting GSH biosynthetic enzyme and inhibit neuroinflammation in vitro. Here we determined 1) the role of cysteamine as a new mechanism by which DMP increases GSH biosynthesis and 2) its ability to inhibit neuroinflammation and neuronal injury in the rat kainate model of epilepsy. DMP depleted cysteamine in a time- and concentration-dependent manner in a cell free system. To guide the in vivo administration of DMP, its pharmacokinetic profile was determined in the plasma, liver, and brain. The results confirmed DMP's ability to cross the blood-brain-barrier. Treatment of rats with DMP (30 mg/kg) depleted cysteamine in the liver and hippocampus that was associated with increased GCL activity in these tissues. GSH levels were significantly increased (20 %) in the hippocampus 1 h after 30 mg/kg DMP administration. Following DMP (30 mg/kg) administration once daily, a marked attenuation of GSH depletion was seen in the SE model. SE-induced inflammatory markers including cytokine release, microglial activation, and neuronal death were significantly attenuated in the hippocampus with DMP treatment. Taken together, these results highlight the importance of restoring redox status with rescue of GSH depletion by DMP in post epileptogenic insults.

Sodium Houttuyfonate Prevents Seizures and Neuronal Cell Loss by Maintaining Glutamatergic System Stability in Male Rats with Kainic Acid-Induced Seizures

The present study evaluated the antiseizure and neuroprotective effects of sodium houttuyfonate (SH), a derivative of Houttuynia cordata Thunb. (H. cordata), in a kainic acid (KA)- induced seizure rat model and its underlying mechanism. Sprague Dawley rats were administered normal saline, SH (50 or 100 mg/kg), or carbamazepine (300 mg/kg) by oral gavage for seven consecutive days before the intraperitoneal administration of KA (15 mg/kg). SH showed antiseizure effects at a dose of 100 mg/kg; it prolonged seizure latency and decreased seizure scores. SH also significantly decreased neuronal loss in the hippocampi of KA-treated rats, which was associated with the prevention of glutamate level increase, the upregulation of glutamate reuptake-associated proteins (excitatory amino acid transporters 1-3), glutamate metabolism enzyme glutamine synthetase, the downregulation of the glutamate synthesis enzyme glutaminase, and significant alterations in the expression of AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor) and NMDA (N-methyl-D-aspartic acid receptor) receptor subunits in the hippocampus. Furthermore, the effects of SH were similar to those of the antiseizure drug carbamazepine. Therefore, the results of the present study suggest that SH has antiseizure effects on KA-induced seizures, possibly through the prevention of glutamatergic alterations. Our findings suggest that SH is a potential alternative treatment that may prevent seizures by preserving the normal glutamatergic system.

A Systematic Review of the Predictive and Diagnostic Uses of Neuroinflammation Biomarkers for Epileptogenesis

A central role for neuroinflammation in epileptogenesis has recently been suggested by several investigations. This systematic review explores the role of inflammatory mediators in epileptogenesis, its association with seizure severity, and its correlation with drug-resistant epilepsy (DRE). The study analysed articles published in JCR journals from 2019 to 2024. The search strategy comprised the MESH, free terms of "Neuroinflammation", and selective searches for the following single biomarkers that had previously been selected from the relevant literature: "High mobility group box 1/HMGB1", "Toll-Like-Receptor 4/TLR-4", "Interleukin-1/IL-1", "Interleukin-6/IL-6", "Transforming growth factor beta/TGF-β", and "Tumour necrosis factor-alpha/TNF-α". These queries were all combined with the MESH terms "Epileptogenesis" and "Epilepsy". We found 243 articles related to epileptogenesis and neuroinflammation, with 356 articles from selective searches by biomarker type. After eliminating duplicates, 324 articles were evaluated, with 272 excluded and 55 evaluated by the authors. A total of 21 articles were included in the qualitative evaluation, including 18 case-control studies, 2 case series, and 1 prospective study. As conclusion, this systematic review provides acceptable support for five biomarkers, including TNF-α and some of its soluble receptors (sTNFr2), HMGB1, TLR-4, CCL2 and IL-33. Certain receptors, cytokines, and chemokines are examples of neuroinflammation-related biomarkers that may be crucial for the early diagnosis of refractory epilepsy or may be connected to the control of epileptic seizures. Their value will be better defined by future studies.

Interictal interleukin-6 and tumor necrosis factor α levels are associated with seizure recurrence in adults with epilepsy

BACKGROUND

Although there are models predicting epilepsy recurrence under different clinical conditions, few studies have examined blood biomarkers. Inflammation plays a crucial role in the occurrence and development of epilepsy. We analyzed inflammatory mediators in a regional hospital-based epilepsy cohort and investigated their relationship with subsequent epilepsy recurrence.

METHODS

Interictal inflammatory mediators were measured in 128 patients diagnosed with epilepsy participating in a prospective study. Inflammatory mediators were compared during the follow-up period between patients who experienced epilepsy recurrence and those who did not. We also assessed the correlation between inflammatory mediators and the time interval until the next recurrence.

RESULTS

Over a median 4-month follow-up period, 41 patients experienced seizure recurrence. Differences in interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) levels were observed between seizure recurrence and non-recurrence groups. After adjusting for covariates through multivariate Cox regression analysis, the patients in the third IL-6 tertile (>2.31 pg/mL; HR: 2.49; 95 % CI: 1.00-6.16; P = 0.049) and in the third TNF-α tertile (>0.74 pg/mL; HR: 2.80; 95 % CI: 1.13-6.92; P = 0.026) had higher risk of seizure recurrence. The time until the next recurrence was negatively correlated with IL-6 level (ρ =  - 0.392, P = 0.011).

CONCLUSION

High levels of IL-6 and TNF-α are associated with a higher possibility of seizure recurrence. Future predictive models should also include inflammatory mediators in addition to clinical variables.

Effect of prednisolone in a kindling model of epileptic seizures in rats on cytokine and intestinal microbiota diversity

Epilepsy is a neurological disease characterized by spontaneous and recurrent seizures. Epileptic seizures can be initiated and facilitated by inflammatory mechanisms. As the dysregulation of the immune system would be involved in epileptogenesis, it is suggested that anti-inflammatory medications could impact epileptic seizures. These medications could potentially have a side effect by altering the structure and composition of the intestinal microbiota. These changes can disrupt microbial homeostasis, leading to dysbiosis and potentially exacerbating intestinal inflammation. We hypothesize that prednisolone may affect the development of epileptic seizures, potentially influencing the diversity of the intestinal microbiota and the regulation of pro-inflammatory cytokines in intestinal tissue. This study aimed to evaluate the effects of prednisolone treatment on epileptic seizures and investigate the effect of this drug on the bacterial diversity of the intestinal microbiota and markers of inflammatory processes in intestinal tissue. We used Male Wistar rat littermates (n = 31, 90-day-old) divided into four groups: positive control treated with 2 mg/kg of diazepam (n = 6), negative control treated with 0.9 g% sodium chloride (n = 6), and the remaining two groups were subjected to treatment with prednisolone, with one receiving 1 mg/kg (n = 9) and the other 5 mg/kg (n = 10). All administrations were performed intraperitoneally (i.p.) over 14 days. To induce the chronic model of epileptic seizures, we administered pentylenetetrazole (PTZ) 25 mg/kg i.p. on alternate days. Seizure latency (n = 6 - 10) and TNF-α and IL-1β concentrations from intestinal samples were measured by ELISA (n = 6 per group), and intestinal microbiota was evaluated with intergenic ribosomal RNA (rRNA) spacer (RISA) analysis (n = 6 per group). The prednisolone treatment demonstrated an increase in the latency time of epileptic seizures and TNF-α and IL-1β concentrations compared to controls. There was no statistically significant difference in intestinal microbiota diversity between the different treatments. However, there was a strong positive correlation between microbial diversity and TNF-α and IL-1β concentrations. The administration of prednisolone yields comparable results to diazepam on increasing latency between seizures, exhibiting promise for its use in clinical studies. Although there were no changes in intestinal microbial diversity, the increase in the TNF-α and IL-1β cytokines in intestinal tissue may be linked to immune system signaling pathways involving the intestinal microbiota. Additional research is necessary to unravel the intricacies of these pathways and to understand their implications for clinical practice.

A high seizure burden increases several prostaglandin species in the hippocampus of a Scn1a+/- mouse model of Dravet syndrome

Dravet syndrome is an intractable epilepsy with a high seizure burden that is resistant to current anti-seizure medications. There is evidence that neuroinflammation plays a role in epilepsy and seizures, however few studies have specifically examined neuroinflammation in Dravet syndrome under conditions of a higher seizure burden. Here we used an established genetic mouse model of Dravet syndrome (Scn1a+/- mice), to examine whether a higher seizure burden impacts the number and morphology of microglia in the hippocampus. Moreover, we examined whether a high seizure burden influences classical inflammatory mediators in this brain region. Scn1a+/- mice with a high seizure burden induced by thermal priming displayed a localised reduction in microglial cell density in the granule cell layer and subgranular zone of the dentate gyrus, regions important to postnatal neurogenesis. However, microglial cell number and morphology remained unchanged in other hippocampal subfields. The high seizure burden in Scn1a+/- mice did not affect hippocampal mRNA expression of classical inflammatory mediators such as interleukin 1β and tumour necrosis factor α, but increased cyclooxygenase 2 (COX-2) expression. We then quantified hippocampal levels of prostanoids that arise from COX-2 mediated metabolism of fatty acids and found that Scn1a+/- mice with a high seizure burden displayed increased hippocampal concentrations of numerous prostaglandins, notably PGF2α, PGE2, PGD2, and 6-K-PGF1A, compared to Scn1a+/- mice with a low seizure burden. In conclusion, a high seizure burden increased hippocampal concentrations of various prostaglandin mediators in a mouse model of Dravet syndrome. Future studies could interrogate the prostaglandin pathways to further better understand their role in the pathophysiology of Dravet syndrome.

Causal links between gut microbiomes, cytokines and risk of different subtypes of epilepsy: a Mendelian randomization study

Objective

Recent research suggests a potential link between the gut microbiome (GM) and epilepsy. We undertook a Mendelian randomization (MR) study to determine the possible causal influence of GM on epilepsy and its various subtypes, and explore whether cytokines act as mediators.

Methods

We utilized Genome-Wide Association Study (GWAS) summary statistics to examine the causal relationships between GM, cytokines, and four epilepsy subtypes. Furthermore, we assessed whether cytokines mediate the relationship between GM and epilepsy. Significant GMs were further investigated using transcriptomic MR analysis with genes mapped from the FUMA GWAS. Sensitivity analyses and reverse MR were conducted for validation, and false discovery rate (FDR) correction was applied for multiple comparisons.

Results

We pinpointed causal relationships between 30 GMs and various epilepsy subtypes. Notably, the Family Veillonellaceae (OR:1.03, 95%CI:1.02-1.05, p = 0.0003) consistently showed a strong positive association with child absence epilepsy, and this causal association endured even after FDR correction (p-FDR < 0.05). Seven cytokines were significantly associated with epilepsy and its subtypes. A mediating role for cytokines has not been demonstrated. Sensitivity tests validated the primary MR analysis outcomes. Additionally, no reverse causality was detected between significant GMs and epilepsy. Of the mapped genes of notable GMs, genes like BLK, FDFT1, DOK2, FAM167A, ZSCAN9, RNGTT, RBM47, DNAJC21, SUMF1, TCF20, GLO1, TMTC1, VAV2, and RNF14 exhibited a profound correlation with the risk factors of epilepsy subtypes.

Conclusion

Our research validates the causal role of GMs and cytokines in various epilepsy subtypes, and there has been no evidence that cytokines play a mediating role between GM and epilepsy. This could provide fresh perspectives for the prevention and treatment of epilepsy.

Anti-epileptic and Neuroprotective Effects of Ultra-low Dose NADPH Oxidase Inhibitor Dextromethorphan on Kainic Acid-induced Chronic Temporal Lobe Epilepsy in Rats

Neuroinflammation mediated by microglia and oxidative stress play pivotal roles in the development of chronic temporal lobe epilepsy (TLE). We postulated that kainic acid (KA)-Induced status epilepticus triggers microglia-dependent inflammation, leading to neuronal damage, a lowered seizure threshold, and the emergence of spontaneous recurrent seizures (SRS). Extensive evidence from our laboratory suggests that dextromethorphan (DM), even in ultra-low doses, has anti-inflammatory and neuroprotective effects in many animal models of neurodegenerative disease. Our results showed that administration of DM (10 ng/kg per day; subcutaneously via osmotic minipump for 4 weeks) significantly mitigated the residual effects of KA, including the frequency of SRS and seizure susceptibility. In addition, DM-treated rats showed improved cognitive function and reduced hippocampal neuronal loss. We found suppressed microglial activation-mediated neuroinflammation and decreased expression of hippocampal gp91phox and p47phox proteins in KA-induced chronic TLE rats. Notably, even after discontinuation of DM treatment, ultra-low doses of DM continued to confer long-term anti-seizure and neuroprotective effects, which were attributed to the inhibition of microglial NADPH oxidase 2 as revealed by mechanistic studies.

TNF-α: A serological marker for evaluating the severity of hippocampal sclerosis in medial temporal lobe epilepsy?

OBJECTIVE

By analysing the difference in TNF-α levels in the peripheral blood of patients with medial temporal lobe epilepsy (mTLE) with or without hippocampal sclerosis and the correlation between TNF-α and N-acetylaspartate levels in the hippocampus, we explored the relationship between TNF-α and the degree of damage to hippocampal sclerosis neurons in medial temporal lobe epilepsy.

METHODS

This is a prospective, population-based study. A total of 71 Patients with medial temporal lobe epilepsy diagnosed by clinical seizures, video-EEG, epileptic sequence MRI, and other imaging examinations were recruited from October 2020 to July 2022 in the Department of Neurology, Affiliated Hospital of Xuzhou Medical University. Twenty age-matched healthy subjects were selected as the control group. The patients were divided into two groups: the medial temporal epilepsy with hippocampal sclerosis group (positive group, mTLE-HS-P group) and the medial temporal epilepsy without hippocampal sclerosis group (negative group, mTLE-HS-N group). The levels of IL-1β, IL-5, IL-6, IL-8, IL-17, IFN-γ and TNF-α in the peripheral blood of the patients in the three groups were detected by multimicrosphere flow immunofluorescence assay. The level of N-acetylaspartate (NAA) in the hippocampus was measured by 1H-MRS. The differences in cytokine levels among the three groups were analysed, and the correlation between cytokine and NAA levels was analysed.

RESULTS

The level of TNF-α in the peripheral blood of the patients in the mTLE-HS-P group was significantly higher than that of the patients in the mTLE-HS-N and healthy control groups, and the level of TNF-α in the patients in the mTLE-HS-N group was significantly higher than that of the patients in the healthy control group. The NAA level in mTLE-HS-P group patients was significantly lower than that of mTLE-HS-N patients and healthy controls, but there was no significant difference between mTLE-HS-N patients and healthy controls (P > 0.05). Spearman correlation analysis showed that TNF-α level (rs = -0.437, P < 0.05) and the longest duration of a single seizure (rs = -0.398, P < 0.05) were negatively correlated with NAA level. Logistic regression analysis showed that there was no significant correlation between the longest duration of a single seizure and hippocampal sclerosis, but TNF-α level was closely related to hippocampal sclerosis in patients with mTLE (OR = 1.315, 95 % CI 1.084-1.595, P = 0.005).

CONCLUSION

The level of TNF-α in the peripheral blood of patients with medial temporal lobe epilepsy with hippocampal sclerosis was higher, and it was correlated with NAA and hippocampal sclerosis. The high expression of TNF-α may be of important value in the evaluation of hippocampal sclerosis patients.

Neuroprotective potential of pyrazole benzenesulfonamide derivative T1 in targeted intervention against PTZ-induced epilepsy-like condition in in vivo zebrafish model

Epilepsy is a chronic neurological disease characterized by a persistent susceptibility to seizures. Pharmaco-resistant epilepsies, impacting around 30 % of patients, highlight the urgent need for improved treatments. Neuroinflammation, prevalent in epileptogenic brain regions, is a key player in epilepsy, prompting the search for new mechanistic therapies. Hence, in this study, we explored the anti-inflammatory potential of pyrazole benzenesulfonamide derivative (T1) against pentylenetetrazole (PTZ) induced epilepsy-like conditions in in-vivo zebrafish model. The results from the survival assay showed 79.97 ± 6.65 % at 150 µM of T1 compared to PTZ-group. The results from reactive oxygen species (ROS), apoptosis and histology analysis showed that T1 significantly reduces cellular damage due to oxidative stress in PTZ-exposed zebrafish. The gene expression analysis and neutral red assay results demonstrated a notable reduction in the inflammatory response in zebrafish pre-treated with T1. Subsequently, the open field test unveiled the anti-convulsant activity of T1, particularly at a concentration of 150 μM. Moreover, both RT-PCR and immunohistochemistry findings indicated a concentration-dependent potential of T1, which inhibited COX-2 in zebrafish exposed to PTZ. In summary, T1 protected zebrafish against PTZ-induced neuronal damage, and behavioural changes by mitigating the inflammatory response through the inhibition of COX-2.

The effect of ferroptosis-related mitochondrial dysfunction in the development of temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is the most common form of epileptic syndrome. It has been established that due to its complex pathogenesis, a considerable proportion of TLE patients often progress to drug-resistant epilepsy. Ferroptosis has emerged as an important neuronal death mechanism in TLE, which is primarily influenced by lipid accumulation and oxidative stress. In previous studies of ferroptosis, more attention has been focused on the impact of changes in the levels of proteins related to the redox equilibrium and signaling pathways on epileptic seizures. However, it is worth noting that the oxidative-reduction changes in different organelles may have different pathophysiological significance in the process of ferroptosis-related diseases. Mitochondria, as a key organelle involved in ferroptosis, its structural damage and functional impairment can lead to energy metabolism disorders and disruption of the excitatory inhibitory balance, significantly increasing the susceptibility to epileptic seizures. Therefore, secondary mitochondrial dysfunction in the process of ferroptosis could play a crucial role in TLE pathogenesis. This review focuses on ferroptosis and mitochondria, discussing the pathogenic role of ferroptosis-related mitochondrial dysfunction in TLE, thus aiming to provide novel insights and potential implications of ferroptosis-related secondary mitochondrial dysfunction in epileptic seizures and to offer new insights for the precise exploration of ferroptosis-related therapeutic targets for TLE patients.

Epilepsy and demyelination: Towards a bidirectional relationship

Demyelination stands out as a prominent feature in individuals with specific types of epilepsy. Concurrently, individuals with demyelinating diseases, such as multiple sclerosis (MS) are at a greater risk of developing epilepsy compared to non-MS individuals. These bidirectional connections raise the question of whether both pathological conditions share common pathogenic mechanisms. This review focuses on the reciprocal relationship between epilepsy and demyelination diseases. We commence with an overview of the neurological basis of epilepsy and demyelination diseases, followed by an exploration of how our comprehension of these two disorders has evolved in tandem. Additionally, we discuss the potential pathogenic mechanisms contributing to the interactive relationship between these two diseases. A more nuanced understanding of the interplay between epilepsy and demyelination diseases has the potential to unveiling the molecular intricacies of their pathological relationships, paving the way for innovative directions in future clinical management and treatment strategies for these diseases.

Astragalus polysaccharides ameliorate epileptogenesis, cognitive impairment, and neuroinflammation in a pentylenetetrazole-induced kindling mouse model

Background: Epilepsy is a prevalent neurological disease where neuroinflammation plays a significant role in epileptogenesis. Recent studies have suggested that Astragalus polysaccharides (APS) have anti-inflammatory properties, which make them a potential candidate for neuroprotection against central nervous system disease. Nevertheless, the extent of their effectiveness in treating epilepsy remains enigmatic. Therefore, our study aims to investigate the potential of APS to mitigate epileptogenesis and its comorbidities by exploring its underlying mechanism. Methods: Initially, we employed pentylenetetrazol-induced seizure mice to validate APS' effectiveness. Subsequently, we employed network pharmacology analysis to probe the possible targets and signaling pathways of APS in treating epilepsy. Ultimately, we verified the key targets and signaling pathways experimentally, predicting their mechanisms of action. Results: APS have been observed to disturb the acquisition process of kindling, leading to reduced seizure scores and a lower incidence of complete kindling. Moreover, APS has been found to improve cognitive impairments and prevent hippocampal neuronal damage during the pentylenetetrazole (PTZ)-kindling process. Subsequent network pharmacology analysis revealed that APS potentially exerted their anti-epileptic effects by targeting cytokine and toll-like receptor 4/nuclear factor kappa B (TLR4/NF-κB) signaling pathways. Finally, experimental findings showed that APS efficiently inhibited the activation of astrocytes and reduced the release of pro-inflammatory mediators, such as interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). In addition, APS impeded the activation of the TLR4/NF-κB signaling cascade in a PTZ-induced kindling mouse model. Conclusion: The outcomes of our study suggest that APS exerts an impact on epileptogenesis and mitigates cognitive impairment by impeding neuroinflammatory processes. The mechanism underlying these observations may be attributed to the modulation of the TLR4/NF-κB signaling pathway, resulting in a reduction of the release of inflammatory mediators. These findings partially agree with the predictions derived from network pharmacology analyses. As such, APS represents a potentially innovative and encouraging adjunct therapeutic option for epileptogenesis and cognitive deficit.

Epidemiology, Risk Factors, and Biomarkers of Post-Traumatic Epilepsy: A Comprehensive Overview

This paper presents an in-depth exploration of Post-Traumatic Epilepsy (PTE), a complex neurological disorder following traumatic brain injury (TBI), characterized by recurrent, unprovoked seizures. With TBI being a global health concern, understanding PTE is crucial for effective diagnosis, management, and prognosis. This study aims to provide a comprehensive overview of the epidemiology, risk factors, and emerging biomarkers of PTE, thereby informing clinical practice and guiding future research. The epidemiological aspect of the study reveals PTE as a significant contributor to acquired epilepsies, with varying incidence influenced by injury severity, age, and intracranial pathologies. The paper delves into the multifactorial nature of PTE risk factors, encompassing clinical, demographic, and genetic elements. Key insights include the association of injury severity, intracranial hemorrhages, and early seizures with increased PTE risk, and the roles of age, gender, and genetic predispositions. Advancements in neuroimaging, electroencephalography, and molecular biology are presented, highlighting their roles in identifying potential PTE biomarkers. These biomarkers, ranging from radiological signs to electroencephalography EEG patterns and molecular indicators, hold promise for enhancing PTE pathogenesis understanding, early diagnosis, and therapeutic guidance. The paper also discusses the critical roles of astrocytes and microglia in PTE, emphasizing the significance of neuroinflammation in PTE development. The insights from this review suggest potential therapeutic targets in neuroinflammation pathways. In conclusion, this paper synthesizes current knowledge in the field, emphasizing the need for continued research and a multidisciplinary approach to effectively manage PTE. Future research directions include longitudinal studies for a better understanding of TBI and PTE outcomes, and the development of targeted interventions based on individualized risk profiles. This research contributes significantly to the broader understanding of epilepsy and TBI.

The longitudinal effects of cannabidiol on brain temperature in patients with treatment-resistant epilepsy

Neuroinflammation (NI) is a key pathophysiological contributor to treatment-resistant epilepsy (TRE) that remains challenging to observe in vivo. Magnetic resonance spectroscopic imaging and thermometry (MRSI-t) is an emerging technique that can be used to non-invasively map brain temperature, whereby brain temperature elevations serve as a surrogate for the cellular and biochemical processes associated with NI. In a previous multimodal imaging study of focal epilepsy patients, we observed MRSI-t-based brain temperature elevations ipsilateral to the seizure onset zone (SOZ) that were concordant with evidence of edema (Sharma et al., 2023). Despite its potential as tool, it is unclear if MRSI-t can monitor changes in brain temperature in response to treatment. We imaged 25 participants approximately 12-weeks apart. Eight patients with TRE were imaged before receiving highly-purified pharmaceutical grade cannabidiol (CBD; pre-CBD) and after 12-weeks of CBD (on-CBD) therapy. Seventeen healthy controls (HCs) were also imaged twice. Repeated measures t-tests computed changes in TRE patients' seizure symptoms, mood, and brain temperature within their respective SOZs. Repeated measures ANOVAs tested Group*Time changes in imaging data. Participants with TRE had abnormally high peak brain temperatures within their SOZs that decreased after CBD initiation (p < 0.0001). Seizure severity scores also improved after CBD initiation (p < 0.001). These findings provide insights into the possible neural effects of CBD, and further demonstrate MRSI-t's potential as a tool for delineating SOZ. Further investigations into MRSI-t as a longitudinal measure of therapy-induced changes in NI are warranted.

A meta-analysis of the changes in the Gut microbiota in patients with intractable epilepsy compared to healthy controls

OBJECTIVE

To explore gut microbiota changes in intractable epilepsy patients compared to healthy control individuals through meta-analysis.

METHODS

PubMed, Web of Science, CNKI, Wanfang, medRxiv, bioRxiv, ilae.org, clinical trial databases, and papers from the International Epilepsy Congress (IEC) were searched, and the literature on the correlation between intractable epilepsy and the gut microbiota reported from database establishment to June 2023 was included. Literature meeting the inclusion criteria was screened, and meta-analysis of the included literature was performed using RevMan5.4 software.

RESULTS

Ten case-control studies were included in the meta-analysis. There were 183 patients with intractable epilepsy and 283 healthy control subjects. The analysis results indicated that Bacteroidetes (MD = -0.64, 95 %-CI = -1.21 to -0.06) and Ruminococcaceae (MD = -1.44, 95 % CI = -1.96 to -0.92) were less abundant in the patients with intractable epilepsy than in the normal population. Proteobacteria (MD = 0.53, 95 % CI = 0.02 to 1.05) and Verrucomicrobia (MD = 0.26, 95 % CI = 0.06 to 0.45) were more abundant in the patients with intractable epilepsy than in the normal population.

CONCLUSION

This meta-analysis indicated that the abundances of Bacteroidetes and Ruminococcaceae were reduced while those of Proteobacteria and Verrucomicrobia were significantly increased in patients with intractable epilepsy. The above changes in these four taxa of the gut microbiota may have been induced by intractable epilepsy, which may increase the risk of seizures. Their roles in the pathogenesis of intractable epilepsy need to be further explored, and related factors that influence microbiota changes should be considered in future studies.

Anti-inflammatory and Antimicrobial Potential of 1, 3, 4-oxadiazoles and its Derivatives: A Review

1, 3, 4-oxadiazole and its derivatives have significant anti-inflammatory and antimicrobial property. Their precise mechanism of action is not known but it is postulated that they act by inhibiting the biosynthesis of certain prostaglandins. 1, 3, 4-oxadiazoles are a class of heterocyclic compounds with wide variety of biological and pharmacological activities. They have been reported to possess analgesic, antimicrobial, antipyretic and anti-inflammatory properties. These compounds are also active against a number of other inflammatory conditions such as arthritis, gout etc. A wide variety of these compounds have been synthesized and some of them are under clinical trials. In this review article, anti-inflammatory and antimicrobial activity of the 1, 3, 4- oxadiazole shall be discussed.

Celecoxib treatment alleviates cerebral injury in a rat model of post-traumatic epilepsy

Background

An important factor contributing to the development and occurrence of post-traumatic epilepsy (PTE) is neuroinflammation and oxidative stress. The effects of celecoxib include inhibiting inflammatory reactions and antioxidant stress and reducing seizures, making it a potential epilepsy treatment solution.

Objective

To observe the effect of celecoxib on early epilepsy in post-traumatic epilepsy rats. Methods: Twenty-four adult healthy male Sprague-Dawley rats were randomly assigned to three groups: sham-operated, PTE, and celecoxib. A rat model of PTE was established by injecting ferrous chloride into the right frontal cortex. Afterward, the behavior of rats was observed and recorded. 3.0T superconducting magnetic resonance imaging (MRI) was used to describe the changes in ADC values of the brain. HE and Nissl staining were also used to detect the damage to frontal lobe neurons. Furthermore, the expression of COX-2 protein in the right frontal lobe was detected by Western blot. Moreover, the contents of IL-1 and TNF-α in the right frontal lobe were detected by enzyme-linked immunosorbent assay.

Results

Compared with the PTE group, the degree of seizures in rats treated with celecoxib declined dramatically (P < 0.05). Celecoxib-treated rats had significant decreases in tissue structural damage and cell death in the brain. The results of the MRI showed that celecoxib reduced the peripheral edema zone and ADC value of the cortex around the damaged area of the right frontal lobe in the celecoxib-treatment group, which was significantly decreased compared with the PTE group (P < 0.05). Furthermore, celecoxib decreased the expression of COX-2, IL-1β, and TNF-α in brain tissue (P < 0.05).

Conclusions

In PTE rats, celecoxib significantly reduced brain damage and effectively reduced seizures. As a result of celecoxib's ability to inhibit inflammation, it can reduce the edema caused by injury in rat brain tissue.

Immunomodulatory and endocrine effects of deep brain stimulation and spinal cord stimulation - A systematic review

INTRODUCTION

Deep Brain Stimulation (DBS) and Spinal Cord Stimulation (SCS) represent burgeoning treatments for diverse neurological disorders. This systematic review aims to consolidate findings on the immunological and endocrine effects of DBS and SCS, shedding light on the intricate mechanisms of neuromodulation.

MATERIALS AND METHODS

This systematic review, aligned with PRISMA protocols, synthesizes findings from 33 references-20 on DBS and 13 on SCS-to unravel the immunological and endocrine impacts of neuromodulation.

RESULTS

DBS interventions exhibited divergent effects on cytokines, with an increase in hepcidin levels and a variable impact on the IL-6/IL-10 ratio. While some studies reported elevated IL-6, animal studies consistently demonstrated a reduction in IL-1β and IL-6, with no significant changes in TNF-α and an increase in IL-10. Noteworthy hormonal changes included decreased corticosterone and ACTH concentrations and increased oxytocin levels following DBS of the hypothalamus. SCS mirrored similar effects on interleukins, indicating a reduction in IL-6 and IL-1β and an increase in IL-10 levels. Additionally, SCS led to reduced VEGF levels and elevated expression of neurotrophic factors such as BDNF and GDNF, particularly under burst stimulation.

CONCLUSIONS

Both DBS and SCS exert anti-inflammatory effects, manifesting as a decrease in pro-inflammatory cytokines alongside the stimulation of anti-inflammatory cytokine synthesis. These findings, observed in both animal and human models, imply that neurostimulation may modify the trajectory of neurological diseases by modulating local immune responses in an immunomodulatory and endocrine manner. This comprehensive exploration sets the stage for future research endeavors in this evolving domain.