Unraveling the Mechanisms of Cannabidiol's Pharmacological Actions: A Comprehensive Research Overview.

Cannabis sativa has long been used for neurological and psychological healing. Recently, cannabidiol (CBD) extracted from cannabis sativa has gained prominence in the medical field due to its non-psychotropic therapeutic effects on the central and peripheral nervous systems. CBD, also acting as a potent antioxidant, displays diverse clinical properties such as anticancer, antiinflammatory, antidepressant, antioxidant, antiemetic, anxiolytic, antiepileptic, and antipsychotic effects. In this review, we summarized the structural activity relationship of CBD with different receptors by both experimental and computational techniques and investigated the mechanism of interaction between related receptors and CBD. The discovery of structural activity relationship between CBD and target receptors would provide a direction to optimize the scaffold of CBD and its derivatives, which would give potential medical applications on CBD-based therapies in various illnesses.

Multi-target Phenylpropanoids Against Epilepsy.

Epilepsy is a neurological disease with no defined cause, characterized by recurrent epileptic seizures. These occur due to the dysregulation of excitatory and inhibitory neurotransmitters in the central nervous system (CNS). Psychopharmaceuticals have undesirable side effects; many patients require more than one pharmacotherapy to control crises. With this in mind, this work emphasizes the discovery of new substances from natural products that can combat epileptic seizures. Using in silico techniques, this review aims to evaluate the antiepileptic and multi-target activity of phenylpropanoid derivatives. Initially, ligand-based virtual screening models (LBVS) were performed with 468 phenylpropanoid compounds to predict biological activities. The LBVS were developed for the targets alpha- amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), voltage-gated calcium channel Ttype (CaV), gamma-aminobutyric acid A (GABAA), gamma-aminobutyric acid transporter type 1 (GAT-1), voltage-gated potassium channel of the Q family (KCNQ), voltage-gated sodium channel (NaV), and N-methyl D-aspartate (NMDA). The compounds that had good results in the LBVS were analyzed for the absorption, distribution, metabolism, excretion, and toxicity (ADMET) parameters, and later, the best molecules were evaluated in the molecular docking consensus. The TR430 compound showed the best results in pharmacokinetic parameters; its oral absorption was 99.03%, it did not violate any Lipinski rule, it showed good bioavailability, and no cytotoxicity was observed either from the molecule or from the metabolites in the evaluated parameters. TR430 was able to bind with GABAA (activation) and AMPA (inhibition) targets and demonstrated good binding energy and significant interactions with both targets. The studied compound showed to be a promising molecule with a possible multi-target activity in both fundamental pharmacological targets for the treatment of epilepsy.

CBD in the Treatment of Epilepsy.

It has been several years since highly purified cannabidiol (CBD) was registered as a medication that can be used in children of at least 2 years of age to treat different types of seizures related to Lennox-Gastaut syndrome (LGS), Dravet syndrome (DS), and more recently tuberous sclerosis complex (TSC). During this time, 39 randomized clinical trials (RCTs) and 13 meta-analyses on the efficacy and safety of CBD treatment have been published. Each of the meta-analyses had its own criteria for the RCTs' inclusion and, therefore, slightly different interpretations of the analyzed data. Each of them contributed in its own way to the understanding of CBD pharmacology, mechanisms of therapeutic action, development of adverse reactions, and drug-drug interactions. Hence, it seemed reasonable to gather the most relevant data in one article and present all the current knowledge on the use of CBD in epilepsy. The results of the 13 meta-analyses presented herein confirmed the effectiveness and safety of CBD in children and adolescents with DREs. In adults, reliable conclusions cannot be drawn due to insufficient data.

Interactions between antiepileptic drugs and direct oral anticoagulants for primary and secondary stroke prevention.

INTRODUCTION: Direct oral anticoagulants (DOAC) are the guideline-recommended therapy for prevention of stroke in atrial fibrillation (AF) and venous thromboembolism. Since approximately 10% of patients using antiepileptic drugs (AED) also receive DOAC, aim of this review is to summarize data about drug-drug interactions (DDI) of DOAC with AED by using data from PubMed until December 2023. AREAS COVERED: Of 49 AED, only 16 have been investigated regarding DDI with DOAC by case reports or observational studies. No increased risk for stroke was reported only for topiramate, zonisamide, pregabalin, and gabapentin, whereas for the remaining 12 AED conflicting results regarding the risk for stroke and bleeding were found. Further 16 AED have the potential for pharmacodynamic or pharmacokinetic DDI, but no data regarding DOAC are available. For the remaining 17 AED it is unknown if they have DDI with DOAC. EXPERT OPINION: Knowledge about pharmacokinetic and pharmacodynamic DDI of AED and DOAC is limited and frequently restricted to in vitro and in vivo findings. Since no data about DDI with DOAC are available for 67% of AED and an increasing number of patients have a combined medication of DOAC and AED, there is an urgent need for research on this topic.

Twenty-first century antiepileptic drugs. An overview of their targets and synthetic approaches.

The therapeutic use of the traditional drugs against epilepsy has been hindered by their toxicity and low selectivity. These limitations have stimulated the design and development of new generations of antiepileptic drugs. This review explores the molecular targets and synthesis of the antiepileptic drugs that have entered the market in the 21st century, with a focus on manufacturer synthesis.

Hippocampal transcriptomic analyses reveal the potential antiapoptotic mechanism of a novel anticonvulsant agent Q808 on pentylenetetrazol-induced epilepsy in rats.

Brain apoptosis is one of the main causes of epileptogenesis. The antiapoptotic effect and potential mechanism of Q808, an innovative anticonvulsant chemical, have never been reported. In this study, the seizure stage and latency to reach stage 2 of pentylenetetrazol (PTZ) seizure rat model treated with Q808 were investigated. The morphological change and neuronal apoptosis in the hippocampus were detected by hematoxylin and eosin (HE) and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining, respectively. The hippocampal transcriptomic changes were observed using RNA sequencing (RNA-seq). The expression levels of hub genes were verified by quantitative reverse-transcription PCR (qRT-PCR). Results revealed that Q808 could allay the seizure score and prolong the stage 2 latency in seizure rats. The morphological changes of neurons and the number of apoptotic cells in the DG area were diminished by Q808 treatment. RNA-seq analysis revealed eight hub genes, including Map2k3, Nfs1, Chchd4, Hdac6, Siglec5, Slc35d3, Entpd1, and LOC103690108, and nine hub pathways among the control, PTZ, and Q808 groups. Hub gene Nfs1 was involved in the hub pathway sulfur relay system, and Map2k3 was involved in the eight remaining hub pathways, including Amyotrophic lateral sclerosis, Cellular senescence, Fc epsilon RI signaling pathway, GnRH signaling pathway, Influenza A, Rap1 signaling pathway, TNF signaling pathway, and Toll-like receptor signaling pathway. qRT-PCR confirmed that the mRNA levels of these hub genes were consistent with the RNA-seq results. Our findings might contribute to further studies exploring the new apoptosis mechanism and actions of Q808.

Oridonin exerts anticonvulsant profile and neuroprotective activity in epileptic mice by inhibiting NLRP3-mediated pyroptosis.

BACKGROUND: Epilepsy is a chronic disabling disease poorly controlled by available antiseizure medications. Oridonin, a bioactive alkaloid with anti-inflammatory properties and neuroprotective effects, can inhibit the increased excitability of neurons caused by glutamate accumulation at the cellular level. However, whether oridonin affects neuronal excitability and whether it has antiepileptic potential has not been reported in animal models or clinical studies. METHOD: Pentylenetetrazol was injected into mice to create a model of chronic epilepsy. Seizure severity was assessed using the Racine scale, and the duration and latency of seizures were observed. Abnormal neuronal discharge was detected using electroencephalography, and neuronal excitability was assessed using calcium imaging. Damage to hippocampal neurons was evaluated using Hematoxylin-Eosin and Nissl staining. The expression of the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome and other pyroptosis-related proteins was determined using western blotting and immunofluorescence. A neuronal pyroptosis model was established using the supernatant of BV2 cells treated with lipopolysaccharide and adenosine triphosphate to stimulate hippocampal neurons. RESULTS: Oridonin (1 and 5 mg/kg) reduced neuronal damage, increased the latency of seizures, and shortened the duration of fully kindled seizures in chronic epilepsy model mice. Oridonin decreased abnormal discharge during epileptic episodes and suppressed increased neuronal excitability. In vitro experiments showed that oridonin alleviated pyroptosis in hippocampal HT22 neurons. CONCLUSION: Oridonin exerts neuroprotective effects by inhibiting pyroptosis through the NLRP3/caspase-1 pathway in chronic epilepsy model mice. It also reduces pyroptosis in hippocampal neurons in vitro, suggesting its potential as a therapy for epilepsy.

Ameliorative effect of Nyctanthes arbor-tristis L. by suppression of pentylenetetrazole-induced kindling in mice: An insight from EEG, neurobehavioral and in-silico studies.

Epilepsy is an abiding condition associated with recurrent seizure attacks along with associated neurological and psychological emanation owing to disparity of excitatory and inhibitory neurotransmission. The current study encompasses the assessment of the Nyctanthes arbor-tristis L. methanolic extract (Na.Cr) in the management of convulsive state and concomitant conditions owing to epilepsy. The latency of seizure incidence was assessed using pentylenetetrazol (PTZ) kindling models along with EEG in Na.Cr pretreated mice, trailed by behavior assessment (anxiety and memory), biochemical assay, histopathological alterations, chemical profiling through GCMS, and molecular docking. The chronic assessment of PTZ-induced kindled mice depicted salvation in a dose-related pattern and outcomes were noticeable with extract at 400 mg/kg. The extract at 400 mg/kg defends the progress of kindling seizures and associated EEG. Co-morbid conditions in mice emanating owing to epileptic outbreaks were validated by behavioral testing and the outcome depicted a noticeable defense related to anxiety (P<0.001) and cognitive deficit (P<0.001) at 400 mg/kg. The isolated brains were evaluated for oxidative stress and the outcome demonstrated a noticeable effect in a dose-dependent pattern. Treatment with Na.Cr. also preserved the brain from PTZ induced neuronal damage as indicated by histopathological analysis. Furthermore, the GCMS outcome predicted 28 compounds abundantly found in the plant. The results congregated in the current experiments deliver valued evidence about the defensive response apportioned by Na.Cr which might be due to decline in oxidative stress, AChE level, and GABAergic modulation. These activities may contribute to fundamental pharmacology and elucidate some mechanisms behind the activities of Nyctanthes arbor-tristis.

Synaptic vesicle protein 2A mitigates parthanatos via apoptosis-inducing factor in a rat model of pharmacoresistant epilepsy.

AIMS: Synaptic vesicle protein 2A (SV2A) is a unique therapeutic target for pharmacoresistant epilepsy (PRE). As seizure-induced neuronal programmed death, parthanatos was rarely reported in PRE. Apoptosis-inducing factor (AIF), which has been implicated in parthanatos, shares a common cytoprotective function with SV2A. We aimed to investigate whether parthanatos participates in PRE and is mitigated by SV2A via AIF. METHODS: An intraperitoneal injection of lithium chloride-pilocarpine was used to establish an epileptic rat model, and phenytoin and phenobarbital sodium were utilized to select PRE and pharmacosensitive rats. The expression of SV2A was manipulated via lentivirus delivery into the hippocampus. Video surveillance was used to assess epileptic ethology. Biochemical tests were employed to test hippocampal tissues following a successful SV2A infection. Molecular dynamic calculations were used to simulate the interaction between SV2A and AIF. RESULTS: Parthanatos core index, PARP1, PAR, nuclear AIF and MIF, γ-H2AX, and TUNEL staining were all increased in PRE. SV2A is bound to AIF to form a stable complex, successfully inhibiting AIF and MIF nuclear translocation and parthanatos and consequently mitigating spontaneous recurrent seizures in PRE. Moreover, parthanatos deteriorated after the SV2A reduction. SIGNIFICANCE: SV2A protected hippocampal neurons and mitigated epileptic seizures by inhibiting parthanatos via binding to AIF in PRE.

Synthesis, evaluation of biological activity and SAR of new thioalkyl derivatives of pyridine.

BACKGROUND: Pyridine and its derivatives play a vital role in medicinal chemistry, serving as key scaffolds for drugs. The ability to bind to biological targets makes pyridine compounds significant, sparking interest in creating new pyridine-based drugs. Thus, the purpose of the research is to synthesize new thioalkyl derivatives of pyridine, predict their biological spectrum, study their psychotropic properties, and based on these findings, perform structure-activity relationships to assess pharmacophore functional groups. METHODS: Classical organic methods were employed for synthesizing new thioalkyl derivatives of pyridine, with a multifaceted pharmacological profiles. Various software packages and methods were employed to evaluate the biological spectrum of the newly synthesized compounds. For the evaluation of neurotropic activity of new synthesized compounds, some biological methods were used according to indicators characterizing anticonvulsant, sedative and antianxiety activity as well as side effects. RESULTS: Effective synthetic methods for 6-amino-4-phenyl-2-thio-2H-thiopyran-5-carboxylic acid ethyl ester, 2-amino substituted thiopyridine derivatives and 6-cycloamino-2-thioalkyl-4-phenylnicotinate derivatives were obtained in high yield. Predicted biological spectra and pharmacokinetic data indicated high gastrointestinal absorption and low blood-brain barrier passage for most compounds and demonstrated potential various biological effects, particularly psychotropic properties. Studied compounds demonstrated high anticonvulsant activity through antagonism with pentylenetetrazole. They exhibited low toxicity without inducing muscle relaxation in the studied doses. In psychotropic studies, the compounds displayed activating, sedative, and anxiolytic effects. Notably, the 6-amino-2-thioalkyl-4-phenylnicotinate derivatives demonstrated significant anxiolytic activity (about four times more compared to diazepam). They also exhibited pronounced sedative effects. Ethyl 2-({2-[(diphenylmethyl)amino]-2-oxoethyl}thio)-4-phenyl-6-pyrrolidin-1-ylnicotinate exhibited anxiolytic activity even two times greater than diazepam. Moreover, all studied compounds showed statistically significant antidepressant effects. Noteworthy ethyl 2-({2-oxo-2-[(tetrahydrofuran-2-ylmethyl)amino]ethyl}thio)-4-phenyl-6-pyrrolidin-1-ylnicotinate showcasing its unique psychotropic effect. CONCLUSIONS: The selected compounds demonstrate anticonvulsant properties, activating behavior, and anxiolytic effects, while simultaneously exhibiting antidepressant effects and these compounds as promising candidates for further exploration in the development of therapeutics with a broad spectrum of neuropsychiatric applications.

Conventional and novel anti-seizure medications reveal a particular role for GABAA in a North Sea progressive myoclonus Epilepsy Drosophila model.

OBJECTIVE: North Sea Progressive Myoclonus Epilepsy (NS-PME) is a rare genetic disorder characterized by ataxia, myoclonus and seizures with a progressive course. Although the cause of NS-PME is known, namely a homozygous mutation in the GOSR2 gene (c.430 G>T; p. Gly144Trp), sufficient treatment is lacking. Despite combinations of on average 3-5 anti-seizure medications (ASMs), debilitating myoclonus and seizures persist. Here we aimed to gain insight into the most effective anti-convulsive target in NS-PME by evaluating the individual effects of ASMs in a NS-PME Drosophila model. METHOD: A previously generated Drosophila model for NS-PME was used displaying progressive heat-sensitive seizures. We used this model to test 1. a first-generation ASM (sodium barbital), 2. common ASMs used in NS-PME (clonazepam, valproic acid, levetiracetam, ethosuximide) and 3. a novel third-generation ASM (ganaxolone) with similar mode of action to sodium barbital. Compounds were administered by adding them to the food in a range of concentrations. After 7 days of treatment, the percentage of heat-induced seizures was determined and compared to non-treated but affected controls. RESULTS: As previously reported in the NS-PME Drosophila model, sodium barbital resulted in significant seizure suppression, with increasing effect at higher dosages. Of the commonly prescribed ASMs, clonazepam and ethosuximide resulted in significant seizure suppression, whereas both valproic acid and levetiracetam did not show any changes in seizures. Interestingly, ganaxolone did result in seizure suppression as well. CONCLUSION: Of the six drugs tested, three of the four that resulted in seizure suppression (sodium barbital, clonazepam, ganaxolone) are primary known for their direct effect on GABAA receptors. This suggests that GABAA could be a potentially important target in the treatment of NS-PME. Consequently, these findings add rationale to the exploration of the clinical effect of ganaxolone in NS-PME and other progressive myoclonus epilepsies.

Novel Alaninamide Derivatives with Drug-like Potential for Development as Antiseizure and Antinociceptive Therapies─In Vitro and In Vivo Characterization.

In the present study, a series of original alaninamide derivatives have been designed applying a combinatorial chemistry approach, synthesized, and characterized in the in vivo and in vitro assays. The obtained molecules showed potent and broad-spectrum activity in basic seizure models, namely, the maximal electroshock (MES) test, the 6 Hz (32 mA) seizure model, and notably, the 6 Hz (44 mA) model of pharmacoresistant seizures. Most potent compounds 26 and 28 displayed the following pharmacological values: ED50 = 64.3 mg/kg (MES), ED50 = 15.6 mg/kg (6 Hz, 32 mA), ED50 = 29.9 mg/kg (6 Hz, 44 mA), and ED50 = 34.9 mg/kg (MES), ED50 = 12.1 mg/kg (6 Hz, 32 mA), ED50 = 29.5 mg/kg (6 Hz, 44 mA), respectively. Additionally, 26 and 28 were effective in the ivPTZ seizure threshold test and had no influence on the grip strength. Moreover, lead compound 28 was tested in the PTZ-induced kindling model, and then, its influence on glutamate and GABA levels in the hippocampus and cortex was evaluated by the high-performance liquid chromatography (HPLC) method. In addition, 28 revealed potent efficacy in formalin-induced tonic pain, capsaicin-induced pain, and oxaliplatin- and streptozotocin-induced peripheral neuropathy. Pharmacokinetic studies and in vitro ADME-Tox data proved favorable drug-like properties of 28. The patch-clamp recordings in rat cortical neurons showed that 28 at a concentration of 10 µM significantly inhibited fast sodium currents. Therefore, 28 seems to be an interesting candidate for future preclinical development in epilepsy and pain indications.

Synthesis, In Vivo Anticonvulsant Activity Evaluation and In Silico Studies of Some Quinazolin-4(3H)-One Derivatives.

Two series, "a" and "b", each consisting of nine chemical compounds, with 2,3-disubstituted quinazolin-4(3H)-one scaffold, were synthesized and evaluated for their anticonvulsant activity. They were investigated as dual potential positive allosteric modulators of the GABAA receptor at the benzodiazepine binding site and inhibitors of carbonic anhydrase II. Quinazolin-4(3H)-one derivatives were evaluated in vivo (D1-3 = 50, 100, 150 mg/kg, administered intraperitoneally) using the pentylenetetrazole (PTZ)-induced seizure model in mice, with phenobarbital and diazepam, as reference anticonvulsant agents. The in silico studies suggested the compounds act as anticonvulsants by binding on the allosteric site of GABAA receptor and not by inhibiting the carbonic anhydrase II, because the ligands-carbonic anhydrase II predicted complexes were unstable in the molecular dynamics simulations. The mechanism targeting GABAA receptor was confirmed through the in vivo flumazenil antagonism assay. The pentylenetetrazole experimental anticonvulsant model indicated that the tested compounds, 1a-9a and 1b-9b, present a potential anticonvulsant activity. The evaluation, considering the percentage of protection against PTZ, latency until the onset of the first seizure, and reduction in the number of seizures, revealed more favorable results for the "b" series, particularly for compound 8b.

Novel diarylated tacrine derivatives: Synthesis, characterization, anticancer, antiepileptic, antibacterial, and antifungal activities.

In this study, our goal was to synthesize novel aryl tacrine derivatives and assess their potential as anticancer, antibacterial agents, and enzyme inhibitors. We adopted a two-step approach, initiating with the synthesis of dibromotacrine derivatives 3 and 4 through the Friedlander reaction. These intermediates underwent further transformation into diarylated tacrine derivatives 3a-e and 4a-e using a Suzuki-Miyaura cross-coupling reaction. Thorough characterization of these novel diarylated tacrines was achieved using various spectroscopic techniques. Our findings highlighted the potent anticancer effects of these innovative compounds across a range of cancer cell lines, including lung, gynecologic, bone, colon, and breast cancers, while demonstrating low cytotoxicity against normal cells. Notably, these compounds surpassed the control drug, 5-Fluorouracil, in terms of antiproliferative activity in numerous cancer cell lines. Moreover, our investigation included an analysis of the inhibitory properties of these novel compounds against various microorganisms and cytosolic carbonic anhydrase enzymes. The results suggest their potential for further exploration as cancer-specific, enzyme inhibitory, and antibacterial therapeutic agents. Notably, four compounds, namely, 5,7-bis(4-(methylthio)phenyl)tacrine (3d), 5,7-bis(4-(trifluoromethoxy)phenyl)tacrine (3e), 2,4-bis(4-(trifluoromethoxy)phenyl)-7,8,9,10-tetrahydro-6H-cyclohepta[b]quinolin-11-amine (4e), and 6,8-dibromotacrine (3), emerged as the most promising candidates for preclinical studies.

Anticonvulsant effects of Paeonia daurica subsp. macrophylla root extracts in pentylenetetrazol-induced seizure models in mice.

INTRODUCTION: In the present study, anticonvulsant effects of aqueous extract (AE), hydro-alcoholic crude extract (HE), and its fractions (F-CHCl3, F-EtOAc, F-MeOH) of Paeonia daurica subsp. macrophylla (P. daurica ssp. macrophylla) root examined by using a pentylenetetrazol-induced model (PTZ) on mice. METHODS: HE and its fractions as well as AE, in concentrations of (100, 200 and 400mg/kg), valproate (Val) (100 and 200mg/kg), and saline (negative control) (10mg/kg) were injected intraperitoneally (i.p.) 30min before PTZ (80mg/kg, i.p.). The time taken before the onset of myoclonic convulsions (MC), MC duration, time taken before the onset of generalized tonic-clonic seizures (GTCS), the duration of GTCS, and the percentage of GTCS and mortality protection recorded. The plant's anticonvulsant mechanisms were assessed using flumazenil (5mg/kg, i.p.) before AE (100, 200, and 400mg/kg, i.p.) injection. GraphPad Prism software was used to compare the differences between various treatment groups with one-way analysis of variance (ANOVA) followed by Tukey-Krammer multiple comparison tests. RESULTS: All the plant samples except F-EtOAc significantly delayed the onset and decreased the duration of PTZ-induced MCS and GTCS, and significantly reduced the GTCS and mortality rate. Pretreatment with flumazenil diminished the significant anticonvulsant effects of AE against PTZ-induced seizures. CONCLUSIONS: It can report that extract of P. daurica ssp. macrophylla might be a helpful guide for future studies in the treatment of epilepsy.

Berberine and hesperidin prevent the memory consolidation impairment induced by pentylenetetrazole in zebrafish.

This study verified the effects of the natural compounds berberine and hesperidin on seizure development and cognitive impairment triggered by pentylenetetrazole (PTZ) in zebrafish. Adult animals were submitted to a training session in the inhibitory avoidance test and, after 10 minutes, they received an intraperitoneal injection of 25, 50, or 100 mg/kg berberine or 100 or 200 mg/kg hesperidin. After 30 minutes, the animals were exposed to 7.5 mM PTZ for 10 minutes. Animals were submitted to the test session 24 h after the training session to verify their cognitive performance. Zebrafish larvae were exposed to 100 µM or 500 µM berberine or 10 µM or 50 µM hesperidin for 30 minutes. After, larvae were exposed to PTZ and had the seizure development evaluated by latency to reach the seizure stages I, II, and III. Adult zebrafish pretreated with 50 mg/kg berberine showed a longer latency to reach stage III. Zebrafish larvae pretreated with 500 µM berberine showed a longer latency to reach stages II and III. Hesperidin did not show any effect on seizure development both in larvae and adult zebrafish. Berberine and hesperidin pretreatments prevented the memory consolidation impairment provoked by PTZ-induced seizures. There were no changes in the distance traveled in adult zebrafish pretreated with berberine or hesperidin. In larval stage, berberine caused no changes in the distance traveled; however, hesperidin increased the locomotion. Our results reinforce the need for investigating new therapeutic alternatives for epilepsy and its comorbidities.

Modulation index predicts the effect of ethosuximide on developmental and epileptic encephalopathy with spike-and-wave activation in sleep.

PURPOSE: In developmental and epileptic encephalopathy with spike-and-wave activation in sleep (DEE-SWAS), the thalamocortical network is suggested to play an important role in the pathophysiology of the progression from focal epilepsy to DEE-SWAS. Ethosuximide (ESM) exerts effects by blocking T-type calcium channels in thalamic neurons. With the thalamocortical network in mind, we studied the prediction of ESM effectiveness in DEE-SWAS treatment using phase-amplitude coupling (PAC) analysis. METHODS: We retrospectively enrolled children with DEE-SWAS who had an electroencephalogram (EEG) recorded between January 2009 and September 2022 and were prescribed ESM at Okayama University Hospital. Only patients whose EEG showed continuous spike-and-wave during sleep were included. We extracted 5-min non-rapid eye movement sleep stage N2 segments from EEG recorded before starting ESM. We calculated the modulation index (MI) as the measure of PAC in pair combination comprising one of two fast oscillation types (gamma, 40-80 Hz; ripples, 80-150 Hz) and one of five slow-wave bands (delta, 0.5-1, 1-2, 2-3, and 3-4 Hz; theta, 4-8 Hz), and compared it between ESM responders and non-responders. RESULTS: We identified 20 children with a diagnosis of DEE-SWAS who took ESM. Fifteen were ESM responders. Regarding gamma oscillations, significant differences were seen only in MI with 0.5-1 Hz slow waves in the frontal pole and occipital regions. Regarding ripples, ESM responders had significantly higher MI in coupling with all slow waves in the frontal pole region, 0.5-1, 3-4, and 4-8 Hz slow waves in the frontal region, 3-4 Hz slow waves in the parietal region, 0.5-1, 2-3, 3-4, and 4-8 Hz slow waves in the occipital region, and 3-4 Hz slow waves in the anterior-temporal region. SIGNIFICANCE: High MI in a wider area of the brain may represent the epileptic network mediated by the thalamus in DEE-SWAS and may be a predictor of ESM effectiveness.

A profile of azetukalner for the treatment of epilepsy: from pharmacology to potential for therapy.

INTRODUCTION: Epilepsies are a group of heterogeneous brain disorder, and antiseizure medications (ASMs) are the mainstay of treatment. Despite the availability of more than 30 drugs, at least one third of individuals with epilepsy are drug-resistant. This emphasizes the need for novel compounds that combine efficacy with improved tolerability. AREAS COVERED: A literature review on the pharmacology, efficacy, tolerability, and safety of azetukalner (XEN1101), a second-generation opener of neuronal potassium channels currently in Phase 3 development as ASM. EXPERT OPINION: Results from the phase 2b clinical trial strongly support the ongoing clinical development of azetukalner as a new ASM. Its pharmacokinetic properties support convenient once-daily dosing, eliminating the need for titration at initiation or tapering at the conclusion of treatment. CYP3A4 is the main enzyme involved in its metabolism and drug-drug interactions can affect the drug exposure. Preliminary analysis of an ongoing open-label study reveals no reported pigmentary abnormalities. The upcoming Phase 3 clinical trials are expected to provide further insight into the efficacy, tolerability, and safety of azetukalner in treating focal-onset and primary generalized tonic-clonic seizures. Structurally distinct from currently marketed ASMs, azetukalner has the potential to be the only-in-class Kv7.2/7.3 opener on the market upon regulatory approval.

Role of non-receptor tyrosine kinases in epilepsy: significance and potential as therapeutic targets.

INTRODUCTION: Epilepsy is a chronic neurological condition characterized by a persistent propensity for seizure generation. About one-third of patients do not achieve seizure control with the first-line treatment options, which include >20 antiseizure medications. It is therefore imperative that new medications with novel targets and mechanisms of action are developed. AREAS COVERED: Clinical studies and preclinical research increasingly implicate Non-receptor tyrosine kinases (nRTKs) in the pathogenesis of epilepsy. To date, several nRTK members have been linked to processes relevant to the development of epilepsy. Therefore, in this review, we provide insight into the molecular mechanisms by which the various nRTK subfamilies can contribute to the pathogenesis of epilepsy. We further highlight the prospective use of specific nRTK inhibitors in the treatment of epilepsy deriving evidence from existing literature providing a rationale for their use as therapeutic targets. EXPERT OPINION: Specific small-molecule inhibitors of NRTKs can be employed for the targeted therapy as already seen in other diseases by examining the precise molecular pathways regulated by them contributing to the development of epilepsy. However, the evidence supporting NRTKs as therapeutic targets are limiting in nature thus, necessitating more research to fully comprehend their function in the development and propagation of seizures.

Pharmacological evaluation of E2730, a novel selective uncompetitive GAT1 inhibitor, on epileptiform activities in resected brain tissues from human focal cortical dysplasia ex vivo.

Focal cortical dysplasia (FCD) is an important etiology of focal epilepsy in children and adults. However, only a few preclinical models sufficiently reproduce the characteristic histopathologic features of FCD. To improve the success rate of clinical trials for antiseizure medications (ASMs) in patients with FCD, more human-relevant preclinical models are needed, and epileptic foci resected from patients are a powerful tool for this purpose. Here, we conducted ex vivo studies using epileptic foci resected from patients with FCD type II to evaluate the pharmacologic effects of the ASM candidate E2730, a selective uncompetitive inhibitor of γ-aminobutyric acid transporter 1. We used the same ex vivo assay system to assess carbamazepine (CBZ), an ASM often prescribed for focal epilepsy, as a reference. At the higher dose tested (200 µM), both E2730 and CBZ suppressed spontaneous epileptiform activities almost completely. At the lower dose (100 µM), CBZ reduced the area of brain tissue showing epileptiform activity, whereas E2730 significantly decreased the number of epileptiforms. These findings suggest that E2730-both as a single agent and in combination with CBZ-merits evaluation in clinical trials involving patients with FCD.