Efficacy Of Antiepileptic Drugs Research Articles

Nano-formulations for the Management of Epilepsy: Synthetic and Herbal Drug Perspectives

Introduction: Epilepsy is a multifaceted neurological disorder impacting many individuals globally. Although the main treatment method is through medicines, many patients do not respond to existing drugs. This has spurred extensive research for new therapeutic targets and drug delivery methods. Inflammation and oxidative stress have been associated with the development and progression of epilepsy. Nanomedicine-based treatments focussing on these pathways could provide a promising way to enhance treatment results. Objective: This review aims to provide insights into enhancing antiepileptic therapy through the development of nanoformulations of synthetic and herbal drugs. Methods: A comprehensive review of existing literature was conducted to evaluate the potential of nanoformulations in improving the delivery and efficacy of antiepileptic drugs. The review covers the pathophysiological hypotheses of epilepsy, including the glutamatergic, GABAergic, oxidative stress, and neuroinflammation hypotheses, and examines the role of neurotransmitter imbalances in seizure activity. Results: Nanoformulations offer promising advantages for epilepsy treatment by enhancing drug delivery across the blood-brain barrier, reducing required dosages, and minimizing side effects. The utilization of nanoparticles can improve the bioavailability and targeting of AEDs, potentially leading to better seizure control. However, challenges such as ensuring biocompatibility and optimizing nanoparticle characteristics remain. Conclusion: While significant progress has been made in understanding epilepsy and developing treatments, the disorder continues to pose challenges. Nanoformulations represent a promising area of research that could lead to more effective and targeted therapies for epilepsy, although further studies are needed to address the associated challenges and fully realize their potential.

Prospects for the use of perampanel in the treatment of epilepsy in patients with malignant gliomas of the brain

Epilepsy occurs in 35-95% of patients with malignant cerebral gliomas of low malignancy and in 29-71% of patients with gliomas of high malignancy. Seizures can be both the first manifestation of malignant cerebral glioma and appear in the postoperative period and during chemoradiotherapy. This requires the use of antiepileptic drugs, which should control the seizure syndrome, provide control and secondary prevention of seizures, without reducing the response of anti-tumour therapy and the the patient QoL. The processes of epileptogenesis and oncogenesis are closely interrelated through common developmental mechanisms in which glutamate plays a key role. Hypersecretion of glutamate is accompanied by increased expression and activation of its receptors, which increases convulsive readiness. This is accompanied by increased level of brain neurotrophic growth factor, the number of synapses between peritumoral neurons and glioma cells, and increased expression of a number of growth factors, which contributes to tumourous proliferation. In this regard, special attention when treating epilepsy in patients with malignant cerebral gliomas is given to perampanel, a glutamate receptor blocker, a 3rd generation antiepileptic drug. The findings show that perampanel not only effectively controls seizures in patients with malignant cerebral gliomas, but also suppresses tumourous proliferation. Perampanel is able to dose-dependently enhance apoptosis and disrupt cell migration in malignant glioma cell lines. The findings have revealed synergistic effect of perampanel in combination with temozolamide. In conditions of chemoradiation therapy perampanel has a protective effect on healthy peritumoral tissues. Undesirable drug reactions during the use of perampanel are infrequent and insignificant. Additional studies are needed to further research the anticonvulsant and antitumour efficacy of perampanel to treat epilepsy in patients with malignant brain tumours.

Systematic Review and Network Meta-Analysis: Efficacy and Safety of Antipsychotics vs Antiepileptics or Lithium for Acute Mania in Children and Adolescents

To compare second-generation antipsychotics (SGAs) and mood stabilizers (MSs) in youth with a bipolar disorder type I (BD-I) manic/mixed episode. A systematic PubMed/Embase/PsycInfo literature search until December 31, 2023, for randomized trials of SGAs or MSs in patients≤18 years of age with BD-I manic/mixed episode was conducted. The study included a network meta-analysis comparing treatments regarding mania symptoms and mania response (co-primary outcomes), and secondary efficacy and tolerability outcomes. Eighteen studies (n= 2844, mean age= 11.74, female participants= 48.0%, mean study duration= 5.4 weeks) comparing 6 SGAs (aripiprazole, asenapine, olanzapine, quetiapine, risperidone, and ziprasidone) and 4 MSs (lithium, oxcarbazepine, topiramate, and valproate) were meta-analyzed. All 6 SGAs outperformed placebo in reducing manic symptomatology, including risperidone (standardized mean difference [SMD]=-1.18, 95% CI=-0.92,-1.45, Confidence in Network Meta-Analysis [CINeMA]= moderate confidence), olanzapine (SMD=-0.77, 95% CI=-0.36,-1.18, low confidence), aripiprazole (SMD=-0.67, 95% CI=-0.33,-1.01, moderate confidence), quetiapine (SMD=-0.60, 95% CI=-0.32,-0.87, high confidence), asenapine (SMD=-0.54, 95% CI=-0.19,-0.89, moderate confidence), and ziprasidone (SMD=-0.43, 95% CI=-0.17, 0.70, low confidence), whereas no mood stabilizer outperformed placebo. Concerning mania response, risperidone (RR= 2.58, 95% CI= 1.88, 3.54, low confidence), olanzapine (RR= 2.42, 95% CI= 1.33, 3.54, very low confidence), aripiprazole (RR= 2.05, 95% CI= 1.44, 2.92, low confidence), quetiapine (RR= 1.89, 95% CI= 1.45n 2.47, moderate confidence), asenapine (RR= 1.81, 95% CI= 1.28, 2.55, very low confidence) and lithium (RR= 1.35, 95% CI= 1.00, 1.83, p= .049, very low confidence) outperformed placebo, without superiority of other MSs vs placebo. Individually, risperidone was more efficacious in reducing manic symptomatology than all other comparators, except olanzapine and topiramate, yet with low/very low confidence, and was associated with increased prolactin and glucose. Pooled together, SGAs outperformed both placebo and MSs for mania symptom reduction (SMD=-0.68, 95% CI=-0.86,-0.51 and SMD=-0.61, 95% CI=-0.82,-0.40, moderate confidence), and mania response (RR= 1.85, 95% CI= 1.53, 2.24 and RR= 1.65, 95% CI= 1.33, 2.04, moderate confidence) without differences between MSs and placebo. There were no significant treatment-placebo differences for all-cause discontinuation, whereas lithium, ziprasidone, and oxcarbazepine were associated with more adverse event-related drop-outs than placebo. Most SGAs were associated with more sedation, weight gain, and metabolic issues vs placebo and MSs. SGAs were more efficacious than placebo and MSs in treating acute mania symptoms, however, their use must be carefully weighed against important side effects.

Use of antiepileptic medications for seizures' prevention during subarachnoid hemorrhage: A retrospective observational study.

The use of prophylactic antiepileptic drugs (AEDs) post-subarachnoid hemorrhage (SAH), particularly aneurysmal SAH, is controversial, with limited data available. This has led the new American Heart Association/American Stroke Association (AHA/ASA) guidelines to recommend against using AEDs. This study is aimed at determining whether the use of AEDs for primary prophylaxis is effective in reducing the incidence of seizures post-SAH. A retrospective observational study was conducted utilizing a reviewing chart for the period starting from June 2015 to the end of 2021. The reviews were conducted in the acute care areas of 2 tertiary hospitals primarily to assess the efficacy of AEDs against seizures in patients with SAH (particularly aneurysmal SAH). This was done by comparing the occurrence of early, late, and overall incidence of seizures between patients who received AEDs versus those who did not. Of the 62 patients, who mostly presented with aneurysmal SAH (71%), 42 received AEDs and 20 did not. Mostly, the baseline characteristics between the 2 groups were comparable. A few patients on AEDs developed early (n = 4/38), late (n = 3/29), and overall seizures (n = 6/33), whereas no early, late, or overall incidence of seizures was presented in the group who did not receive AEDs. However, this difference showed no significance (P > .05). The subjects who were given AEDs showed significantly longer hospital stays (42.11 ± 51.43 vs 14.10 ± 7.17; P = .002) and higher mortality rates (7/11 vs 0/11; P = .026). For all patients who received AEDs for prophylaxis, the overall incidence of seizures was negatively associated with the Glasgow coma scale (OR: 0.798; 95% CI 0.657-0.978; P = .022). Our findings support the 2023 AHA/ASA guideline recommendation to avoid using routine AEDs for prophylaxis for all SAH patients. Proper and careful stratification methods should be implemented in each given scenario.

Antiepileptic Drugs as Prophylaxis for Seizures after Excision of Brain Tumors

Abstract Background Seizures are the most common & most serious side effect of cranial surgery. The latter condition requires chronic treatment with Antiepileptic drugs (AEDs) and comes with relevant socioeconomic sequelae. The routine prophylactic use of AEDs for people undergoing tumor resection has remained controversial due to the risk of postoperative seizures. Some Neurosurgeons are advocates to the use of AEDs to reduce the risk of these seizures. Objective To evaluate the efficacy of prophylactic AEDs routinely in brain tumor patients without previous history of seizures. Primary objective has been to identify the efficacy of AEDs in perioperative seizure prophylaxis. Secondary objective has been to highlight the most common type of post-operative AEDs. Methods All available studies from 2000-2021 including randomized or non-randomized clinical trials, prospective or retrospective observational cohort studies, and case series of six or more cases that address these criteria have been collected. Results Our search concluded that the most common type of post-operative seizure is the Early seizure which is of total 87 patients representing 12.3% of seizure reported patients, yet when comparing the P-value between the Early & late seizure it has a P-value of 0.415 which is nonsignificant rendering the comparison redundant. The Most common types of AED used are Phenytoin (PHT) 89 (71.8%) & Levetiracetam (LEV) 109 (81.8%). To measure the efficacy of AEDs two groups of patients with no history of AED administration or seizures preoperatively were created, one the control group of 268 participants were not administered AEDs postoperatively only 32 (11.94%) of them suffered from seizures postoperatively. The other group of 171 participants were administered the AEDs postoperatively only 25 (14.62%) of these participants suffered from postoperative seizure. Comparing both of these results statistically it had a P-value of 0.416 which is non-Significant statistically. On interpreting these results was that the AED have no influence in controlling the seizures. Conclusion Postoperative seizures are one of the main complications of brain tumor surgery. Neurosurgeons have a strong belief more of tradition that preventing seizures with Anti-Epileptic Drugs (AEDs) as a sort of seizure prophylaxis is not only effective but also necessary. Finally, there is not enough evidence of sufficient quality available to suggest that antiepileptic drugs AEDs treatment can or cannot be recommended to reduce Post-craniotomy seizures.

Sustained Inhibition of GABA-AT by OV329 Enhances Neuronal Inhibition and Prevents Development of Benzodiazepine Refractory Seizures.

γ-Aminobutyric acid (GABA) is the principal inhibitory neurotransmitter in the adult brain which mediates its rapid effects on neuronal excitability via ionotropic GABAA receptors. GABA levels in the brain are critically dependent upon GABA-aminotransferase (GABA-AT) which promotes its degradation. Vigabatrin, a low-affinity GABA-AT inhibitor, exhibits anticonvulsant efficacy, but its use is limited due to cumulative ocular toxicity. OV329 is a rationally designed, next-generation GABA-AT inhibitor with enhanced potency. We demonstrate that sustained exposure to OV329 in mice reduces GABA-AT activity and subsequently elevates GABA levels in the brain. Parallel increases in the efficacy of GABAergic inhibition were evident, together with elevations in electroencephalographic delta power. Consistent with this, OV329 exposure reduced the severity of status epilepticus and the development of benzodiazepine refractory seizures. Thus, OV329 may be of utility in treating seizure disorders and associated pathologies that result from neuronal hyperexcitability.

Effect of carbamazepine-beta-cyclodextrin inclusion complex on seizure-like events in an in vitro model of temporal lobe epilepsy

Abstract Objective: Pharmacoresistant epilepsy represents a significant global health challenge, necessitating novel therapeutic approaches. Despite advances in antiseizure medications, many patients remain treatment-resistant partially due to complex pharmacokinetic issues. Beta-cyclodextrin, known for enhancing drug solubility and stability, offers potential solutions by forming inclusion complexes, thereby improving anti-seizure medication’s efficacy. This study aimed to investigate the effect of beta-cyclodextrin and beta-cyclodextrin-complexed carbamazepine on epileptiform activities, using an in vitro model of temporal lobe epilepsy. Methods: Seizure-like neuronal activity was induced using the low-magnesium model. Local field potentials were recorded from transverse rat hippocampal slices immersed in epileptogenic artificial cerebrospinal fluid, followed by the administration of either beta-cyclodextrin or carbamazepine, the latter in 100 micromolar concentration. Results: Beta cyclodextrin, applied alone, significantly reduced the duration of interictal and ictal phases while increasing the frequency of seizure-like events. Carbamazepine exhibited an important anticonvulsant effect, significantly reducing ictal and postictal phase durations. However, the frequency of seizure-like events was increased. Notably, in some of the slices, carbamazepine completely suppressed epileptiform activity. Conclusions: Beta cyclodextrin had an effect on its own; it shortened seizure durations and increased their frequency. Carbamazepine in complexed form, as used in our study, exhibited anticonvulsant efficacy, emphasizing the feasibility of solubility enhancement by this method. This study provides insights into potential therapeutic strategies for pharmacoresistant temporal lobe epilepsy, improving the pharmacological properties of the drugs. As cyclodextrins emerge as promising excipients for antiepileptic drugs with poor solubility, more effort is needed in order to elucidate the underlying mechanisms of their effects.

Seizure suppression and neuroprotection in soman-exposed rats following delayed intramuscular treatment of adenosine A1 receptor agonist as an adjunct to standard medical treatment

Soman produces excitotoxic effects by inhibiting acetylcholinesterase in the cholinergic synapses and neuromuscular junctions, resulting in soman-induced sustained status epilepticus (SSE). Our previous work showed delayed intramuscular (i.m.) treatment with A1 adenosine receptor agonist N-bicyclo-[2.2.1]-hept-2-yl-5′-chloro-5′-deoxyadenosine (ENBA) alone suppressed soman-induced SSE and prevented neuropathology. Using this same rat soman seizure model, we tested if delayed therapy with ENBA (60 mg/kg, i.m.) would terminate seizure, protect neuropathology, and aid in survival when given in conjunction with current standard medical countermeasures (MCMs): atropine sulfate, 2-PAM, and midazolam (MDZ). Either 15- or 30-min following soman-induced SSE onset, male rats received atropine and 2-PAM plus either MDZ or MDZ + ENBA. Electroencephalographic (EEG) activity, physiologic parameters, and motor function were recorded. Either 2- or 14-days following exposure surviving rats were euthanized and perfused for histology. All animals treated with MDZ + ENBA at both time points had 100% EEG seizure termination and reduced total neuropathology compared to animals treated with MDZ (2-day, p = 0.015 for 15-min, p = 0.002 for 30-min; 14-day, p < 0.001 for 15-min, p = 0.006 for 30-min), showing ENBA enhanced MDZ's anticonvulsant and neuroprotectant efficacy. However, combined MDZ + ENBA treatment, when compared to MDZ treatment groups, had a reduction in the 14-day survival rate regardless of treatment time, indicating possible enhancement of MDZ's neuronal inhibitory effects by ENBA. Based on our findings, ENBA shows promise as an anticonvulsant and neuroprotectant in a combined treatment regimen following soman exposure; when given as an adjunct to standard MCMs, the dose of ENBA needs to be adjusted.

Anticonvulsants in the Treatment of Behavioral and Psychological Symptoms in Dementia: A Systematic Review

ObjectivesBehavioral and psychological symptoms of dementia (BPSD) are common and impart a significant burden to patients, caregivers, and the health system. However, there are few pharmacological options for treating BPSD. We conducted a systematic review of clinical trials examining the efficacy of anticonvulsants in BPSD. MethodsWe searched five electronic databases through January 2023, for randomized controlled trials and systematic reviews evaluating the efficacy of non-benzodiazepine anticonvulsants for the treatment of BPSD. We used the Cochrane risk of bias tool to ascertain the risk of bias in included trials. Because statistical pooling of results using meta-analysis was not feasible, we synthesized findings using the Cochrane Synthesis Without Meta-analysis reporting guidelines. ResultsWe identified 12 studies, including randomized controlled trials (RCTs) and 1 systematic review. Five RCTs evaluating valproic acid were synthesized by a recent Cochrane review which concluded that this drug is likely ineffective for BPSD. We extracted data from 6 trials involving 248 individuals comparing non-benzodiazepine anticonvulsants to either placebo or risperidone. Four trials (n = 97 participants) evaluated carbamazepine, only one of which demonstrated an improvement in the Brief Psychiatric Rating Scale measuring agitation, hostility, psychosis, and withdrawal/depression (effect size: 1.13; 95% confidence interval [CI]: 0.54–1.73) relative to placebo. Adverse effects were more common in patients receiving carbamazepine (20/27; 74%) relative to placebo (5/24; 21%). There is low quality evidence that oxcarbazepine is likely ineffective and that topiramate may be comparable to risperidone. ConclusionAnticonvulsants are unlikely to be effective in BPSD, although the quality of existing evidence is low.

The Role of Pharmacists' Interventions in Increasing Medication Adherence of Patients With Epilepsy: A Scoping Review.

Epilepsy is a chronic disease that requires long-term treatment and intervention from health workers. Medication adherence is a factor that influences the success of therapy for patients with epilepsy. Therefore, this study aimed to analyze the role of pharmacists in improving the clinical outcomes of epilepsy patients, focusing on medication adherence. A scoping literature search was conducted through the ScienceDirect, PubMed, and Google Scholar databases. The literature search included all original articles published in English until August 2023 for which the full text was available. This scoping review was carried out by a team consisting of pharmacists and neurologists following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) Extension for Scoping Reviews and the Joanna Briggs Institute guidelines, including 5 steps: identifying research questions, finding relevant articles, selecting articles, presenting data, and compiling the results. The literature search yielded 10 studies that discussed pharmacist interventions for patients with epilepsy. Five articles described educational interventions involving drug-related counseling with pharmacists. Two articles focused on similar pharmacist interventions through patient education, both verbal and written. Three articles discussed an epilepsy review service, a multidisciplinary intervention program involving pharmacists and other health workers, and a mixed intervention combining education and training with therapy-based behavioral interventions. Pharmacist interventions have been shown to be effective in improving medication adherence in patients with epilepsy. Furthermore, these interventions play a crucial role in improving other therapeutic outcomes, including patients' knowledge of self-management, perceptions of illness, the efficacy of antiepileptic drugs in controlling seizures, and overall quality of life.

Effect of a Declined Plasma Concentration of Valproic Acid Induced by Meropenem on the Antiepileptic Efficacy of Valproic Acid.

This study aimed to indicate whether a declined plasma concentration of valproic acid (VPA) induced by co-administration of meropenem (MEPM) could affect the antiepileptic efficacy of VPA. We retrospectively reviewed data of hospitalized patients who were diagnosed with status epilepticus or epilepsy between 2010 and 2019. Patients co-administered VPA and MEPM during hospitalization were screened and assigned to the exposure group, while those co-administerd VPA and other broad-spectrum antibiotics were allocated to the control group. The exposure group and control group included 50 and 11 patients, respectively. With a similar dosage of VPA, the plasma concentration of VPA significantly decreased during co-administration (24.6 ± 4.3 μg/mL) compared with that before co-administration (88.8 ± 13.6 μg/mL, p < 0.0001), and it was partly recovered with the termination of co-administration (39.8 ± 13.2 μg/mL, p = 0.163) in the exposure group. The inverse probability of treatment weighting estimated the treatment efficacy via changes in seizure frequency, seizure duration, and concomitant use of antiepileptic drugs, which were not significantly different between the exposure and control groups. In the exposure group, there was no significant differences in seizure frequency between the periods of before-during and before-after (p = 0.074 and 0.153, respectively). Seizure duration during VPA-MEPM co-administration was not significantly different from that before co-administration (p = 0.291). In this study, the reduced plasma concentration of VPA induced by the co-administration of MEPM did not affect the antiepileptic efficacy of VPA. This conclusion should be interpreted with caution, and more research is warranted. Chinese Clinical Trial Registry: ChiCTR2000034567. Registered on 10 July 2020.

Unveiling the effects of nanoparticles-based antiepileptic drugs: Systematic review of in vivo studies

Background: Resistance and side effects of antiepileptic drugs (AEDs) pose a challenge in epilepsy therapy due to the limited drug bioavailability in penetrating the Blood-Brain Barrier (BBB). Nanoparticles can be one solution by encapsulating AEDs to enhance drug distribution to target cells. This study systematically assesses 1) the characteristics of nanoparticles, and 2) the potential of nanoparticle AEDs in managing seizures in experimental animal models. Methods: This systematic literature review is limited to studies published between 2013 and July 2023 in the PubMed, ScienceDirect, ProQuest, MEDLINE, and Scopus databases. Inclusion criteria encompass studies involving animal models of epilepsy, that exploring nanoparticle-based of AEDs. These studies compare the characteristics of nanoparticles and their antiepileptic efficacy with non-nanoparticle groups. Review articles, publications in non-English languages, and ongoing studies without published results are excluded. Result and Discussion: Fourteen studies met the inclusion criteria for this research. All studies utilized nanoparticles (n = 14). Lipid nanoparticles have a more compact size than any other nanoparticle, while the combination preparation method has an optimal nanoparticle formation in both lipid and polymeric nanoparticles. In animal model results indicated that nanoparticle-based drugs were beneficial in reducing seizure scores, improving seizure onset latency, and providing neuroprotective effects. Conclusion: The characteristics of nanoparticle drug delivery varied, influenced by formulation factors and preparation methods. Nanoparticle-based AEDs exhibit higher efficacy compared to conventional AEDs. All studies included present an opportunity for the development of epilepsy therapies, although future studies are needed to confirm these findings.

Deferasirox exerts anti-epileptic effects by improving brain iron homeostasis via regulation of ITPRIP

Epilepsy constitutes a global health concern, affecting millions of individuals and approximately one-third of patients exhibit drug resistance. Recent investigations have revealed alterations in cerebral iron content in both epilepsy patients and animal models. However, the extant literature lacks a comprehensive exploration into the ramifications of modulating iron homeostasis as an intervention in epilepsy. This study investigated the impact of deferasirox, a iron ion chelator, on epilepsy. This study unequivocally substantiated the antiepileptic efficacy of deferasirox in a kainic acid-induced epilepsy model. Furthermore, deferasirox administration mitigated seizure susceptibility in a pentylenetetrazol-induced kindling model. Conversely, the augmentation of iron levels through supplementation has emerged as a potential exacerbating factor in the precipitating onset of epilepsy. Intriguingly, our investigation revealed a hitherto unreported discovery: ITPRIP was identified as a pivotal modulator of excitatory synaptic transmission, regulating seizures in response to deferasirox treatment. In summary, our findings indicate that deferasirox exerts its antiepileptic effects through the precise targeting of ITPRIP and amelioration of cerebral iron homeostasis, suggesting that deferasirox is a promising and novel therapeutic avenue for interventions in epilepsy.

The efficacy and safety of novel antiepileptic drugs in treatment of epilepsy of patients with brain tumors.

This meta-analysis aimed to assess the effectiveness and safety of novel antiepileptic drugs (AEDs) in treating epilepsy in patients with brain tumors (BTRE). A search was conducted on PubMed, EMBASE, Web of Science, and the Cochrane Library from inception to February 2023, with English language restriction. In this meta-analysis, 18 clinical trials involving 755 BTRE patients were included to assess the efficacy and safety of novel AEDs in BTRE treatment. At the last follow-up, a ≥50% reduction in seizure frequency was experienced by 72% of patients (random-effects model, 95% CI = 0.64-0.78) using novel AEDs. At the last follow-up, seizure freedom was experienced by 34% of patients (random-effects model, 95% CI = 0.28-0.41) using novel AEDs. The pooled incidence of AEs was found to be 19% (95% CI: 13%-26%), with a withdrawal rate due to adverse effects of only 3%. Comparable efficacy and incidence of adverse effects were observed between lacosamide and perampanel. This meta-analysis suggests that novel antiepileptic drugs are deemed effective for seizure control in brain tumor patients, particularly when used as adjunctive therapy. Although lacosamide and perampanel received more focus in studies, no significant difference was observed in the efficacy and adverse reactions of these two drugs in seizure control. Further randomized controlled trials are deemed necessary to validate our findings.

An Update on Stiripentol Mechanisms of Action: A Narrative Review.

Stiripentol (Diacomit®) (STP) is an orally active antiseizure medication (ASM) indicated as adjunctive therapy, for the treatment of seizures associated with Dravet syndrome (DS), a severe form of childhood epilepsy, in conjunction with clobazam and, in some regions valproic acid. Since the discovery of STP, several mechanisms of action (MoA) have been described that may explain its specific effect on seizures associated with DS. STP is mainly considered as a potentiator of gamma-aminobutyric acid (GABA) neurotransmission: (i) via uptake blockade, (ii) inhibition of degradation, but also (iii) as a positive allosteric modulator of GABAA receptors, especially those containing α3 and δ subunits. Blockade of voltage-gated sodium and T-type calcium channels, which is classically associated with anticonvulsant and neuroprotective properties, has also been demonstrated for STP. Finally, several studies indicate that STP could regulate glucose energy metabolism and inhibit lactate dehydrogenase. STP is also an inhibitor of several cytochrome P450 enzymes involved in the metabolism of other ASMs, contributing to boost their anticonvulsant efficacy as add-on therapy. These different MoAs involved in treatment of DS and recent data suggest a potential for STP to treat other neurological or non-neurological diseases.

Ketogenic diet-produced β-hydroxybutyric acid accumulates brain GABA and increases GABA/glutamate ratio to inhibit epilepsy

Ketogenic diet (KD) alleviates refractory epilepsy and reduces seizures in children. However, the metabolic/cell biologic mechanisms by which the KD exerts its antiepileptic efficacy remain elusive. Herein, we report that KD-produced β-hydroxybutyric acid (BHB) augments brain gamma-aminobutyric acid (GABA) and the GABA/glutamate ratio to inhibit epilepsy. The KD ameliorated pentetrazol-induced epilepsy in mice. Mechanistically, KD-produced BHB, but not other ketone bodies, inhibited HDAC1/HDAC2, increased H3K27 acetylation, and transcriptionally upregulated SIRT4 and glutamate decarboxylase 1 (GAD1). BHB-induced SIRT4 de-carbamylated and inactivated glutamate dehydrogenase to preserve glutamate for GABA synthesis, and GAD1 upregulation increased mouse brain GABA/glutamate ratio to inhibit neuron excitation. BHB administration in mice inhibited epilepsy induced by pentetrazol. BHB-mediated relief of epilepsy required high GABA level and GABA/glutamate ratio. These results identified BHB as the major antiepileptic metabolite of the KD and suggested that BHB may serve as an alternative and less toxic antiepileptic agent than KD.

“Three-in-one” strategy of trifluoromethyl regulated blood-brain barrier permeable fluorescent probe for peroxynitrite and antiepileptic evaluation of edaravone

Epilepsy, as a chronic neurological disease of the brain, is closely related to oxidative stress, and the peroxynitrite (ONOO−) significantly rise up in this event. Therefore, ONOO− is considered as a potential biomarker for early prediction of epilepsy. However, some potential diagnostic reagents for epilepsy are hindered by the blood-brain barrier (BBB). Meanwhile, “drug repurposing” is attracting a growing interest. Edaravone (EDA), as a first-line drug in the clinical treatment of cerebral ischemia, plays antioxidant roles in scavenging free radicals, promising potential antiepileptic activity. Thus, it is imperative to develop fluorescent probes for monitoring ONOO− fluctuations in the epileptic brain. Hence, we proposed a novel fluorescent probe with the thiocarbonate as the promising recognition unit for ONOO− and dicyanoisophorone derivative as the fluorophore. Moreover, by the “three-in-one” strategy, the introduction of trifluoromethyl into DCI-ONOO-3 can extend the emission wavelength of the fluorophore, shorten the response and increase lipophilicity. Consequently, DCI-ONOO-3 was used for monitoring ONOO− fluxes in brain of epileptic mice and evaluating the antiepileptic efficacy of EDA. It opens up a new way for the design of BBB permeable fluorescent probes, and provides a convincing new method for the diagnosis and treatment of epilepsy.

Management strategies for refractory status epilepticus

Refractory status epilepticus (RSE) is defined as the persistence of either clinical or electrographic seizures despite the administration of appropriate doses of an initial benzodiazepine and suitable second-line antiepileptic drugs (AEDs). The Neurocritical Care Society and the American Epilepsy Society have proposed a treatment paradigm for the management of convulsive status epilepticus (CSE). The third-line therapy in refractory CSE may involve general anesthesia using intravenous midazolam, propofol, or other agents, while recent evidence supports the use of ketamine to manage RSE in both adults and children. However, although these treatment strategies are frequently employed in nonconvulsive status epilepticus (NCSE), the efficacy of AEDs and anesthetics in NCSE has not been thoroughly investigated. Recent evidence has demonstrated the safety and efficacy of newer AEDs, including levetiracetam and lacosamide, in the treatment of status epilepticus (SE) and RSE, which also encompasses NCSE. Use of multiple combinations of various intravenous AEDs can also be considered in NCSE before the administration of general anesthesia. In addition, AEDs alone exhibit limited effectiveness in managing SE for new-onset RSE (NORSE) and its subset, febrile infection-related epilepsy syndrome. Therefore, in cases of refractory status, it is imperative to explore treatment options beyond AEDs, including immunotherapy and the incorporation of a ketogenic diet. The present review suggests treatment approaches for RSE based on subgroups, including CSE, NCSE, and NORSE. A discussion of recent clinical studies on AEDs and anesthetics in the management of RSE, as well as proposed treatment methods for NORSE, is also provided.

TAT-Modified Martentoxin Displays Intravenous Antiseizure Activities.

Epilepsy is a chronic disease of brain dysfunction, which arises from imbalance between excitatory and inhibitory activities in neural circuits. Previously, we reported that peptide Martentoxin (MarTX), from scorpion Buthus martensii Karsch, displayed antiseizure activities by specifically inhibiting BK(α + β4) channel currents. Injection of MarTX into the hippocampal region of mice significantly alleviated convulsive seizures. However, intravenous injection of MarTX had no antiepileptic efficacy due to the blood-brain barrier (BBB). To address this, here, we designed cell-penetrating peptide TAT-modified MarTX, in which the linker containing three glycines was put between TAT and the N-terminus of MarTX (forming MTX-N-TAT) or between TAT and the C-terminus of MarTX (forming MTX-C-TAT), respectively. We prepared them in a large amount through Escherichia coli overexpression system and then probed their antiseizure activities. Our results indicated that intravenous injection of MTX-C-TAT showed significant therapeutic efficacy of antiseizure. It increased seizure latency, reduced the total seizure duration and the number of seizures at stages 3, 4, and 5, inhibited hippocampal neuronal hyperexcitability, and exhibited neuroprotective effects on hippocampal neurons. These studies implied that MTX-C-TAT displayed intravenous antiseizure activities properly through crossing BBB and would be a potential antiepileptic drug in the future.

KRM–II–81 suppresses epileptifom activity across the neural network of cortical tissue from a patient with pharmacoresistant epilepsy

A clinical case of a 19-year-old male patient with pharmacoresistant seizures occurring following parieto-occipital tumor-resection at age 6 is described. Seizure surgery work-up included prolonged video EEG monitoring and head CT without contrast. Seizure focus was localized to the left temporal lobe, and we felt that the patient was an excellent candidate for seizure surgery. The patient underwent a left frontotemporal craniotomy for removal of the seizure focus with intraoperative electrocorticography (ECoG) conducted pre and post resection. ECoG recordings pre- and post-resection confirmed resolution of seizure generation. Imaging obtained immediately postoperatively showed complete resection of the residual tumor with no evidence of recurrence in follow-ups. A year after the surgery the patient is seizure-free but remains on seizure medication. With the patient's consent the excised epileptogenic tissue was used for ex-vivo research studies. The microelectrode recordings confirmed epileptiform activity in the excised tissue incubated in excitatory artificial cerebrospinal fluid. The epileptiform activity in the epileptogenic tissue was suppressed by addition of KRM–II–81, a novel α2/3 subtype preferring GABAA receptor (GABAAR) potentiator with previously demonstrated antiepileptic efficacy in multiple animal models of epilepsy and with reduced potential for CNS side-effects compared to classical benzodiazepine GABAAR potentiators. These findings support the proposition that KRM–II–81 might reduce seizure burden in pharmacoresistant patients.