Combination antioxidant therapy prevents epileptogenesis and modifies chronic epilepsy

The effects of leptin and cannabinoid CB1 receptor agonist/antagonist in cerebral tissues of epileptic rats

OBJECTIVE

In this study, the effects of leptin, cannabinoid-1 (CB1) receptor agonist ACEA and antagonist AM251, and the interactions between leptin and CB1 receptor agonist/antagonist on oxidant and antioxidant enzymes in the cerebrum, cerebellum, and pedunculus cerebri tissue samples were investigated in the penicillin-induced epileptic model.

METHODS

Male Wistar albino rats (n=56) were included in this study. In anesthetized animals, 500 IU penicillin-G potassium was injected into the cortex to induce epileptiform activity. Leptin (1 μg), ACEA (7.5 μg), AM251 (0.25 μg), and the combinations of the leptin+ACEA and leptin+AM251 were administered intracerebroventricularly (i.c.v.) after penicillin injections. Malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx) levels were measured in the cerebral tissue samples and plasma with the ELISA method.

RESULTS

MDA levels increased, while SOD and GPx levels decreased after penicillin injection in the cerebrum and cerebellum. The efficacy of penicillin on SOD, MDA and GPx levels was further enhanced after leptin or AM251 injections. Whereas, ACEA decreased the MDA levels and increased GPx levels compared with the penicillin group. Administration of AM251+leptin did not change any oxidation parameter compared with the AM251. Furthermore, co-administration of ACEA and leptin significantly increased oxidative stress compared with the ACEA-treated group by increasing MDA and decreasing GPx levels.

CONCLUSION

It was concluded that leptin reversed the effect of ACEA on oxidative stress. Co-administration of AM251 and leptin did not change oxidative stress compared with the AM251-treated group suggesting AM251 and leptin affect oxidative stress using the same pathways.

The Contributions of Thrombospondin-1 to Epilepsy Formation

Epilepsy is a neural network disorder caused by uncontrolled neuronal hyperexcitability induced by an imbalance between excitatory and inhibitory networks. Abnormal synaptogenesis plays a vital role in the formation of overexcited networks. Recent evidence has confirmed that thrombospondin-1 (TSP-1), mainly secreted by astrocytes, is a critical cytokine that regulates synaptogenesis during epileptogenesis. Furthermore, numerous studies have reported that TSP-1 is also involved in other processes, such as angiogenesis, neuroinflammation, and regulation of Ca2+ homeostasis, which are closely associated with the occurrence and development of epilepsy. In this review, we summarize the potential contributions of TSP-1 to epilepsy development.

Diet-derived circulating antioxidants and risk of epilepsy: A study combining metabolomics and mendelian randomization

Background

Previous studies offer inconclusive results on the association between diet-derived circulating antioxidants and epilepsy.

Objective

This study aims to assess oxidative stress presence in epilepsy patients' circulation and investigate the causal link between diet-derived circulating antioxidants and epilepsy.

Methods

Untargeted metabolomics analysis was conducted on plasma samples from 62 epileptic patients and 20 healthy individuals to evaluate oxidative stress based on metabolite alterations in epilepsy patients' circulation. Two-sample Mendelian Randomization (MR) analysis examined the causation between diet-derived circulating antioxidants (measured by absolute levels and relative metabolite concentrations) and epilepsy, utilizing the inverse-variance weighted (IVW) method as the primary outcome, with complementary MR analysis methods (MR Egger, weighted median, weighted mode, and simple mode).

Results

Untargeted metabolomics analysis revealed elevated circulating oxidizing metabolites (palmitic acid, oleic acid, linoleic acid, and myristic acid) and reduced reducing metabolites (glutamine) in epilepsy patients, providing robust evidence of oxidative stress. The IVW analysis indicated significantly reduced epilepsy risk (odds ratio: 0.552; 95% confidence interval: 0.335-0.905, P = 0.018) with genetically determined higher absolute circulating β-carotene. However, other diet-derived circulating antioxidants (lycopene, retinol, ascorbic acid, and selenium) and antioxidant metabolites (α-tocopherol, γ-tocopherol, ascorbic acid, and retinol) did not significantly associate with epilepsy risk. Additional MR analysis methods and heterogeneity assessments confirmed the results' robustness.

Conclusion

This study provides compelling evidence of oxidative stress in epilepsy patients' circulation. However, the majority of diet-derived circulating antioxidants (lycopene, retinol, ascorbic acid, vitamin E, and selenium) are unlikely to causally associate with reduced epilepsy risk, except for β-carotene.

NOX-induced oxidative stress is a primary trigger of major neurodegenerative disorders

Neurodegenerative diseases (NDDs) causing cognitive impairment and dementia are difficult to treat due to the lack of understanding of primary initiating factors. Meanwhile, major sporadic NDDs share many risk factors and exhibit similar pathologies in their early stages, indicating the existence of common initiation pathways. Glucose hypometabolism associated with oxidative stress is one such primary, early and shared pathology, and a likely major cause of detrimental disease-associated cascades; targeting this common pathology may therefore be an effective preventative strategy for most sporadic NDDs. However, its exact cause and trigger remain unclear. Recent research suggests that early oxidative stress caused by NADPH oxidase (NOX) activation is a shared initiating mechanism among major sporadic NDDs and could prove to be the long-sought ubiquitous NDD trigger. We focus on two major NDDs - Alzheimer's disease (AD) and Parkinson's disease (PD), as well as on acquired epilepsy which is an increasingly recognized comorbidity in NDDs. We also discuss available data suggesting the relevance of the proposed mechanisms to other NDDs. We delve into the commonalities among these NDDs in neuroinflammation and NOX involvement to identify potential therapeutic targets and gain a deeper understanding of the underlying causes of NDDs.

Repurposing dimethyl fumarate as an antiepileptogenic and disease-modifying treatment for drug-resistant epilepsy

BACKGROUND

Epilepsy affects over 65 million people worldwide and significantly burdens patients, caregivers, and society. Drug-resistant epilepsy occurs in approximately 30% of patients and growing evidence indicates that oxidative stress contributes to the development of such epilepsies. Activation of the Nrf2 pathway, which is involved in cellular defense, offers a potential strategy for reducing oxidative stress and epilepsy treatment. Dimethyl fumarate (DMF), an Nrf2 activator, exhibits antioxidant and anti-inflammatory effects and is used to treat multiple sclerosis.

METHODS

The expression of Nrf2 and its related genes in vehicle or DMF treated rats were determined via RT-PCR and Western blot analysis. Neuronal cell death was evaluated by immunohistochemical staining. The effects of DMF in preventing the onset of epilepsy and modifying the disease were investigated in the kainic acid-induced status epilepticus model of temporal lobe epilepsy in rats. The open field, elevated plus maze and T-Maze spontaneous alteration tests were used for behavioral assessments.

RESULTS

We demonstrate that administration of DMF following status epilepticus increased Nrf2 activity, attenuated status epilepticus-induced neuronal cell death, and decreased seizure frequency and the total number of seizures compared to vehicle-treated animals. Moreover, DMF treatment reversed epilepsy-induced behavioral deficits in the treated rats. Moreover, DMF treatment even when initiated well after the diagnosis of epilepsy, reduced symptomatic seizures long after the drug was eliminated from the body.

CONCLUSIONS

Taken together, these findings suggest that DMF, through the activation of Nrf2, has the potential to serve as a therapeutic target for preventing epileptogenesis and modifying epilepsy.

Ethnic, Botanic, Phytochemistry and Pharmacology of the Acorus L. Genus: A Review

The genus Acorus, a perennial monocotyledonous-class herb and part of the Acoraceae family, is widely distributed in the temperate and subtropical zones of the Northern and Southern Hemispheres. Acorus is rich in biological activities and can be used to treat various diseases of the nervous system, cardiovascular system, and digestive system, including Alzheimer's disease, depression, epilepsy, hyperlipidemia, and indigestion. Recently, it has been widely used to improve eutrophic water and control heavy-metal-polluted water. Thus far, only three species of Acorus have been reported in terms of chemical components and pharmacological activities. Previously published reviews have not further distinguished or comprehensively expounded the chemical components and pharmacological activities of Acorus plants. By carrying out a literature search, we collected documents closely related to Acorus published from 1956 to 2022. We then performed a comprehensive and systematic review of the genus Acorus from different perspectives, including botanical aspects, ethnic applications, phytochemistry aspects, and pharmacological aspects. Our aim was to provide a basis for further research and the development of new concepts.

The Interplay between Mitochondrial Dysfunction and Ferroptosis during Ischemia-Associated Central Nervous System Diseases

Cerebral ischemia, a leading cause of disability and mortality worldwide, triggers a cascade of molecular and cellular pathologies linked to several central nervous system (CNS) disorders. These disorders primarily encompass ischemic stroke, Alzheimer's disease (AD), Parkinson's disease (PD), epilepsy, and other CNS conditions. Despite substantial progress in understanding and treating the underlying pathological processes in various neurological diseases, there is still a notable absence of effective therapeutic approaches aimed specifically at mitigating the damage caused by these illnesses. Remarkably, ischemia causes severe damage to cells in ischemia-associated CNS diseases. Cerebral ischemia initiates oxygen and glucose deprivation, which subsequently promotes mitochondrial dysfunction, including mitochondrial permeability transition pore (MPTP) opening, mitophagy dysfunction, and excessive mitochondrial fission, triggering various forms of cell death such as autophagy, apoptosis, as well as ferroptosis. Ferroptosis, a novel type of regulated cell death (RCD), is characterized by iron-dependent accumulation of lethal reactive oxygen species (ROS) and lipid peroxidation. Mitochondrial dysfunction and ferroptosis both play critical roles in the pathogenic progression of ischemia-associated CNS diseases. In recent years, growing evidence has indicated that mitochondrial dysfunction interplays with ferroptosis to aggravate cerebral ischemia injury. However, the potential connections between mitochondrial dysfunction and ferroptosis in cerebral ischemia have not yet been clarified. Thus, we analyzed the underlying mechanism between mitochondrial dysfunction and ferroptosis in ischemia-associated CNS diseases. We also discovered that GSH depletion and GPX4 inactivation cause lipoxygenase activation and calcium influx following cerebral ischemia injury, resulting in MPTP opening and mitochondrial dysfunction. Additionally, dysfunction in mitochondrial electron transport and an imbalanced fusion-to-fission ratio can lead to the accumulation of ROS and iron overload, which further contribute to the occurrence of ferroptosis. This creates a vicious cycle that continuously worsens cerebral ischemia injury. In this study, our focus is on exploring the interplay between mitochondrial dysfunction and ferroptosis, which may offer new insights into potential therapeutic approaches for the treatment of ischemia-associated CNS diseases.

Insights on antioxidant therapeutic strategies in type 2 diabetes mellitus: A narrative review of randomized control trials

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a metabolic disease of impaired glucose utilization. Imbalance in generation and elimination of free radicals generate oxidative stress which modulates glucose metabolism and insulin regulation, resulting in the occurrence and progression of diabetes and associated complications. Antioxidant supplements in T2DM can be seen as a potential preventive and effective therapeutic strategy.

AIM

To compare randomized controlled trials (RCTs) in which antioxidants have been shown to have a therapeutic effect in T2DM patients.

METHODS

We systematically searched the electronic database PubMed by keywords. RCTs evaluating the effect of antioxidant therapy on glycaemic control as well as oxidant and antioxidant status as primary outcomes were included. The outcomes considered were: A reduction in blood glucose; changes in oxidative stress and antioxidant markers. Full-length papers of the shortlisted articles were assessed for the eligibility criteria and 17 RCTs were included.

RESULTS

The administration of fixed-dose antioxidants significantly reduces fasting blood sugar and glycated hemoglobin and is associated with decreased malondialdehyde, advanced oxidation protein products, and increased total antioxidant capacity.

CONCLUSION

Antioxidant supplements can be a beneficial approach for the treatment of T2DM.

Therapeutic Strategies to Ameliorate Neuronal Damage in Epilepsy by Regulating Oxidative Stress, Mitochondrial Dysfunction, and Neuroinflammation

Epilepsy is a central nervous system disorder involving spontaneous and recurring seizures that affects 50 million individuals globally. Because approximately one-third of patients with epilepsy do not respond to drug therapy, the development of new therapeutic strategies against epilepsy could be beneficial. Oxidative stress and mitochondrial dysfunction are frequently observed in epilepsy. Additionally, neuroinflammation is increasingly understood to contribute to the pathogenesis of epilepsy. Mitochondrial dysfunction is also recognized for its contributions to neuronal excitability and apoptosis, which can lead to neuronal loss in epilepsy. This review focuses on the roles of oxidative damage, mitochondrial dysfunction, NAPDH oxidase, the blood-brain barrier, excitotoxicity, and neuroinflammation in the development of epilepsy. We also review the therapies used to treat epilepsy and prevent seizures, including anti-seizure medications, anti-epileptic drugs, anti-inflammatory therapies, and antioxidant therapies. In addition, we review the use of neuromodulation and surgery in the treatment of epilepsy. Finally, we present the role of dietary and nutritional strategies in the management of epilepsy, including the ketogenic diet and the intake of vitamins, polyphenols, and flavonoids. By reviewing available interventions and research on the pathophysiology of epilepsy, this review points to areas of further development for therapies that can manage epilepsy.

ROS/Electro Dual-Reactive Nanogel for Targeting Epileptic Foci to Remodel Aberrant Circuits and Inflammatory Microenvironment

Medicinal treatment against epilepsy is faced with intractable problems, especially epileptogenesis that cannot be blocked by clinical antiepileptic drugs (AEDs) during the latency of epilepsy. Abnormal circuits of neurons interact with the inflammatory microenvironment of glial cells in epileptic foci, resulting in recurrent seizures and refractory epilepsy. Herein, we have selected phenytoin (PHT) as a model drug to derive a ROS-responsive and consuming prodrug, which is combined with an electro-responsive group (sulfonate sodium, SS) and an epileptic focus-recognizing group (α-methyl-l-tryptophan, AMT) to form hydrogel nanoparticles (i.e., a nanogel). The nanogel will target epileptic foci, release PHT in response to a high concentration of reactive oxygen species (ROS) in the microenvironment, and inhibit overexcited circuits. Meanwhile, with the clearance of ROS, the nanogel can also reduce oxidative stress and alleviate microenvironment inflammation. Thus, a synergistic regulation of epileptic lesions will be achieved. Our nanogel is expected to provide a more comprehensive strategy for antiepileptic treatment.

Protective Effect of Sulforaphane on Oxidative Stress and Mitochondrial Dysfunction Associated with Status Epilepticus in Immature Rats

The present study aimed to elucidate the effect of sulforaphane (a natural isothiocyanate) on oxidative stress and mitochondrial dysfunction during and at selected periods following status epilepticus (SE) induced in immature 12-day-old rats by Li-pilocarpine. Dihydroethidium was employed for the detection of superoxide anions, immunoblot analyses for 3-nitrotyrosine (3-NT) and 4-hydroxynonenal (4-HNE) levels and respiratory chain complex I activity for evaluation of mitochondrial function. Sulforaphane was given i.p. in two doses (5 mg/kg each), at PD 10 and PD 11, respectively. The findings of the present study indicate that both the acute phase of SE and the early period of epileptogenesis (1 week and 3 weeks following SE induction) are associated with oxidative stress (documented by the enhanced superoxide anion production and the increased levels of 3-NT and 4-HNE) and the persisting deficiency of complex I activity. Pretreatment with sulforaphane either completely prevented or significantly reduced markers of both oxidative stress and mitochondrial dysfunction. Since sulforaphane had no direct anti-seizure effect, the findings suggest that the ability of sulforaphane to activate Nrf2 is most likely responsible for the observed protective effect. Nrf2-ARE signaling pathway can be considered a promising target for novel therapies of epilepsy, particularly when new compounds, possessing inhibitory activity against protein-protein interaction between Nrf2 and its repressor protein Keap1, with less "off-target" effects and, importantly, with an optimal permeability and bioavailability properties, become available commercially.

Nrf2 is expressed more extensively in neurons than in astrocytes following an acute epileptic seizure in rats

The modulation of the nuclear factor erythroid 2-like 2 (Nrf2) activity has been reported to be implicated in the pathology of various neurological disorders, including epilepsy. Previous studies have demonstrated that Nrf2 is activated in the post-status epilepticus rat model; however, the spatiotemporal as well as cell type-specific expression of Nrf2 following brief epileptic seizures remains unclear. Here, we evaluated how an acute epileptic seizure affected the expression of Nrf2 and its downstream genes in the rats' cortex and the hippocampus up to 1 week following the induced seizure. We found that after a pentylenetetrazol-induced seizure, Nrf2 significantly increased at 24 h at the mRNA level and 3 h at the protein level in the cortex. In the hippocampus, the Nrf2 mRNA level peaked at 3 h after the seizure, and no significant changes were observed in the protein level. Interestingly, the mRNA level of Nrf2 downstream genes peaked at 3-6 h after seizure in both the cortex and the hippocampus. A significant increase in the expression of Nrf2 was observed in the neuronal population of CA1 and CA3 regions of the hippocampus, as well as in the cortex. Moreover, we observed no change in the co-localization of Nrf2 with astrocytes neither in the cortex nor in CA1 and CA3. Our results revealed that following a brief acute epileptic seizure, the expression of Nrf2 and its downstream genes is transiently increased and peaked at early timepoints after the seizure predominantly in the hippocampus, and this expression is restricted to the neuronal population.

Allopurinol and ellagic acid decrease epileptiform activity and the severity of convulsive behavior in a model of status epilepticus

BACKGROUND

During status epilepticus, severe seizures can occur, generating recurrent cycles of excitotoxicity and oxidative stress that cause neuronal damage and cell death. The administration of agents with antioxidant properties represents a therapeutic alternative aimed at reducing the severity of status epilepticus and mitigating the neurobiological consequences that precede them.

OBJECTIVE

The objective of this work was to evaluate the antiseizure effect of the antioxidants allopurinol (ALL) and ellagic acid during status epilepticus induced by pilocarpine (PILO).

METHODS

Male Wistar rats (200-250 g) were injected with ALL (50 mg/kg) or ellagic acid (50 mg/kg), 30 min before PILO administration (pretreatment) or 60 min after the beginning of status epilepticus, to evaluate the antiseizure effect of these drugs on epileptiform activity and convulsive behavior.

RESULTS

ALL or ellagic acid administration before or after PILO significantly decreased the epileptiform activity and the severity of convulsive behavior. Better efficacy was observed when the drugs were administered as a pretreatment, increasing the latency time of the appearance of status epilepticus from 27.2 ± 2.6 to 45.8 ± 3.31 min, and significantly reducing the amplitude of epileptiform discharges by 53.5% with ALL and 68.9% with ellagic acid.

CONCLUSION

The antioxidants ALL and ellagic acid showed an antiseizure effect, representing an alternative to reduce epileptiform activity and severity of convulsive behavior during status epilepticus, an effect that may be used as adjuvants to mitigate or reduce oxidative damage processes.

Reactive oxygen species in status epilepticus

It has long been recognized that status epilepticus can cause considerable neuronal damage, and this has become one of its defining features. The mechanisms underlying this damage are less clear. Excessive activation of NMDA receptors results in large rises in internal calcium, which eventually lead to neuronal death. Between NMDA receptor activation and neuronal death are a number of intermediary steps, key among which is the generation of free radicals and reactive oxygen and nitrogen species. Although it has long been thought that mitochondria are the primary source for reactive oxygen species, more recent evidence has pointed to a prominent role of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, an enzyme localized in cell membranes. There is burgeoning in vivo and in vitro evidence that therapies that target the production or removal of reactive oxygen species are not only effective neuroprotectants following status epilepticus, but also potently antiepileptogenic. Moreover, combining therapies targeted at inhibiting NADPH oxidase and at increasing endogenous antioxidants seems to offer the greatest benefits.

Nrf2 is predominantly expressed in hippocampal neurons in a rat model of temporal lobe epilepsy

BACKGROUND

Drug resistance is a particular problem in patients with temporal lobe epilepsy, where seizures originate mainly from the hippocampus. Many of these epilepsies are acquired conditions following an insult to the brain such as a prolonged seizure. Such conditions are characterized by pathophysiological mechanisms including massive oxidative stress that synergistically mediate the secondary brain damage, contributing to the development of epilepsy. The transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2) has emerged in recent years as an attractive therapeutic approach targeting to upregulate the antioxidative defenses in the cell, to ameliorate the oxidative stress-induced damage. Thus, it is important to understand the characteristics of Nrf2 activation during epileptogenesis and epilepsy. Here, we studied the temporal, regional, and cell-type specific expression of Nrf2 in the brain, in a rat model of temporal lobe epilepsy.

RESULTS

Early after status-epilepticus, Nrf2 is mainly activated in the hippocampus and maintained during the whole period of epileptogenesis. Only transient expression of Nrf2 was observed in the cortex. Nevertheless, the expression of several Nrf2 antioxidant target genes was increased within 24 h after status-epilepticus in both the cortex and the hippocampus. We demonstrated that after status-epilepticus in rats, Nrf2 is predominantly expressed in neurons in the CA1 and CA3 regions of the hippocampus, and only astrocytes in the CA1 increase their Nrf2 expression.

CONCLUSIONS

In conclusion, our data identify previously unrecognized spatial and cell-type dependent activation of Nrf2 during epilepsy development, highlighting the need for a time-controlled, and cell-type specific activation of the Nrf2 pathway for mediating anti-oxidant response after brain insult, to modify the development of epilepsy.

Attenuation of Seizures, Cognitive Deficits, and Brain Histopathology by Phytochemicals of Imperata cylindrica (L.) P. Beauv (Poaceae) in Acute and Chronic Mutant Drosophila melanogaster Epilepsy Models

Imperata cylindrica is a globally distributed plant known for its antiepileptic attributes, but there is a scarcity of robust evidence for its efficacy. The study investigated neuroprotective attributes of Imperata cylindrica root extract on neuropathological features of epilepsy in a Drosophila melanogaster mutant model of epilepsy. It was conducted on 10-day-old (at the initiation of study) male post-eclosion bang-senseless paralytic Drosophila (parabss1) involved acute (1-3 h) and chronic (6-18 days) experiments; n = 50 flies per group (convulsions tests); n = 100 flies per group (learning/memory tests and histological examination). Administrations were done in 1 g standard fly food, per os. The mutant flies of study (parabss1) showed marked age-dependent progressive brain neurodegeneration and axonal degeneration, significant (P < 0.05) bang sensitivity and convulsions, and cognitive deficits due to up-regulation of the paralytic gene in our mutants. The neuropathological findings were significantly (P < 0.05) alleviated in dose and duration-dependent fashions to near normal/normal after acute and chronic treatment with extract similar to sodium valproate. Therefore, para is expressed in neurons of brain tissues in our mutant flies to bring about epilepsy phenotypes and behaviors of the current juvenile and old-adult mutant D. melanogaster models of epilepsy. The herb exerts neuroprotection by anticonvulsant and antiepileptogenic mechanisms in mutant D. melanogaster due to plant flavonoids, polyphenols, and chromones (1 and 2) which exert antioxidative and receptor or voltage-gated sodium ion channels' inhibitory properties, and thus causing reduced inflammation and apoptosis, increased tissue repair, and improved cell biology in the brain of mutant flies. The methanol root extract provides anticonvulsant and antiepileptogenic medicinal values which protect epileptic D. melanogaster. Therefore, the herb should be advanced for more experimental and clinical studies to confirm its efficacy in treating epilepsy.

The inhibition of PGAM5 suppresses seizures in a kainate-induced epilepsy model via mitophagy reduction

Background

Epilepsy is a common neurological disease, and excessive mitophagy is considered as one of the major triggers of epilepsy. Mitophagy is a crucial pathway affecting reactive oxygen species. Phosphoglycerate mutase 5 (PGAM5) is a protein phosphatase present in mitochondria that regulates many biological processes including mitophagy and cell death. However, the mechanism of PGAM5 in epilepsy remains unclear. The purpose of the present study was to examine whether PGAM5 affects epilepsy through PTEN-induced putative kinase 1 (PINK1)-mediated mitophagy.

Methods

After the knockdown of PGAM5 expression by the adeno-associated virus, an epilepsy model was created by kainic acid. Next, the seizure activity was recorded by local field potentials before evaluating the level of mitochondrial autophagy marker proteins. Lastly, the ultrastructure of mitochondria, neuronal damage and oxidative stress levels were further observed.

Results

A higher PGAM5 level was found in epilepsy, and its cellular localization was in neurons. The interactions between PGAM5 and PINK1 in epilepsy were further found. After the knockdown of PGAM5, the level of PINK1 and light chain 3B was decreased and the expression of the translocase of the inner mitochondrial membrane 23 and translocase of the outer mitochondrial membrane 20 were both increased. Knockdown of PGAM5 also resulted in reduced neuronal damage, decreased malondialdehyde levels, decreased reactive oxygen species production and increased superoxide dismutase activity. In addition, the duration of spontaneous seizure-like events (SLEs), the number of SLEs and the time spent in SLEs were all reduced in the epilepsy model after inhibition of PGAM5 expression.

Conclusion

Inhibition of PGAM5 expression reduces seizures via inhibiting PINK1-mediated mitophagy.

Specific inhibition of NADPH oxidase 2 modifies chronic epilepsy

Recent work by us and others has implicated NADPH oxidase (NOX) enzymes as main producers of reactive oxygen species (ROS) following a brain insult such as status epilepticus, contributing to neuronal damage and development of epilepsy. Although several NOX isoforms have been examined in the context of epilepsy, most attention has focused on NOX2. In this present study, we demonstrate the effect of gp91ds-tat, a specific competitive inhibitor of NOX2, in in vitro epileptiform activity model as well as in temporal lobe epilepsy (TLE) model in rats. We showed that in in vitro seizure model, gp91ds-tat modulated Ca²⁺ oscillation, prevented epileptiform activity-induced ROS generation, mitochondrial depolarization, and neuronal death. Administration of gp91ds-tat 1 h after kainic acid-induced status epilepticus significantly decreased the expression of NOX2, as well as the overall NOX activity in the cortex and the hippocampus. Finally, we showed that upon continuous intracerebroventricular administration to epileptic rats, gp91ds-tat significantly reduced the seizure frequency and the total number of seizures post-treatment compared to the scrambled peptide-treated animals. The results of the study suggest that NOX2 may have an important effect on modulation of epileptiform activity and has a critical role in mediating seizure-induced NOX activation, ROS generation and oxidative stress in the brain, and thus significantly contributes to development of epilepsy following a brain insult.

Pharmacotherapeutic potential of walnut (Juglans spp.) in age-related neurological disorders

Global and regional trends of population aging spotlight major public health concerns. As one of the most common adverse prognostic factors, advanced age is associated with a remarkable incidence risk of many non-communicable diseases, affecting major organ systems of the human body. Age-dependent factors and molecular processes can change the nervous system's normal function and lead to neurodegenerative disorders. Oxidative stress results from of a shift toward reactive oxygen species (ROS) production in the equilibrium between ROS generation and the antioxidant defense system. Oxidative stress and neuroinflammation caused by Amyloid-ß protein deposition in the human brain are the most likely pathogenesis of Alzheimer's disease (AD). Walnut extracts could reduce Amyloid-ß fibrillation and aggregation, indicating their beneficial effects on memory and cognition. Walnut can also improve movement disabilities in Parkinson's disease due to their antioxidant and neuroprotective effect by reducing ROS and nitric oxide (NO) generation and suppressing oxidative stress. It is noteworthy that Walnut compounds have potential antiproliferative effects on Glioblastoma (the most aggressive primary cerebral neoplasm). This effective therapeutic agent can stimulate apoptosis of glioma cells in response to oxidative stress, concurrent with preventing angiogenesis and migration of tumor cells, improving the quality of life and life expectancy of patients with glioblastoma. Antioxidant Phenolic compounds of the Walnut kernel could explain the significant anti-convulsion ability of Walnut to provide good prevention and treatment for epileptic seizures. Moreover, the anti-inflammatory effect of Walnut oil could be beneficial in treating multiple sclerosis. In this study, we review the pharmaceutical properties of Walnut in age-related neurological disorders.

ROS-removing nano-medicine for navigating inflammatory microenvironment to enhance anti-epileptic therapy

As a neurological disorder in the brain, epilepsy is not only associated with abnormal synchronized discharging of neurons, but also inseparable from non-neuronal elements in the altered microenvironment. Anti-epileptic drugs (AEDs) merely focusing on neuronal circuits frequently turn out deficient, which is necessitating comprehensive strategies of medications to cover over-exciting neurons, activated glial cells, oxidative stress and chronic inflammation synchronously. Therefore, we would report the design of a polymeric micelle drug delivery system that was functioned with brain targeting and cerebral microenvironment modulation. In brief, reactive oxygen species (ROS)-sensitive phenylboronic ester was conjugated with poly-ethylene glycol (PEG) to form amphiphilic copolymers. Additionally, dehydroascorbic acid (DHAA), an analogue of glucose, was applied to target glucose transporter 1 (GLUT1) and facilitate micelle penetration across the blood‒brain barrier (BBB). A classic hydrophobic AED, lamotrigine (LTG), was encapsulated in the micelles via self-assembly. When administrated and transferred across the BBB, ROS-scavenging polymers were expected to integrate anti-oxidation, anti-inflammation and neuro-electric modulation into one strategy. Moreover, micelles would alter LTG distribution in vivo with improved efficacy. Overall, the combined anti-epileptic therapy might provide effective opinions on how to maximize neuroprotection during early epileptogenesis.

Spatial, temporal, and cell-type-specific expression of NADPH Oxidase isoforms following seizure models in rats

The NADPH Oxidase (NOX) enzymes are key producers of reactive oxygen species (ROS) and consist of seven different isoforms, distributed across the tissues and cell types. The increasing level of ROS induces oxidative stress playing a crucial role in neuronal death and the development of epilepsy. Recently, NOX2 was reported as a primary source of ROS production, activated by NMDA receptor, a crucial marker of epilepsy development. Here, we demonstrate spatial, temporal, and cellular expression of NOX2 and NOX4 complexes in in-vitro and in-vivo seizure models. We showed that the expression of NOX2 and NOX4 was increased in the initial 24 h following a brief seizure induced by pentylenetetrazol. Interestingly, while this elevated level returns to baseline 48 h following seizure in the cortex, in the hippocampus these levels remain elevated up to one week following the seizure. Moreover, we showed that 1- and 2- weeks following status epilepticus (SE), expression of NOX2 and NOX4 remains significantly elevated both in the cortex and the hippocampus. Furthermore, in in-vitro seizure model, NOX2 and NOX4 isoforms were overexpressed in neurons and astrocytes following seizures. These results suggest that NOX2 and NOX4 in the brain have a transient response to seizures, and these responses temporally vary depending on, seizure duration, brain region (cortex or hippocampus), and cell types.

Crosstalk between neuroinflammation and oxidative stress in epilepsy

The roles of both neuroinflammation and oxidative stress in the pathophysiology of epilepsy have begun to receive considerable attention in recent years. However, these concepts are predominantly studied as separate entities despite the evidence that neuroinflammatory and redox-based signaling cascades have significant crosstalk. Oxidative post-translational modifications have been demonstrated to directly influence the function of key neuroinflammatory mediators. Neuroinflammation can further be controlled on the transcriptional level as the transcriptional regulators NF-KB and nrf2 are activated by reactive oxygen species. Further, neuroinflammation can induce the increased expression and activity of NADPH oxidase, leading to a highly oxidative environment. These factors additionally influence mitochondria function and the metabolic status of neurons and glia, which are already metabolically stressed in epilepsy. Given the implication of this relationship to disease pathology, this review explores the numerous mechanisms by which neuroinflammation and oxidative stress influence one another in the context of epilepsy. We further examine the efficacy of treatments targeting oxidative stress and redox regulation in animal and human epilepsies in the literature that warrant further investigation. Treatment approaches aimed at rectifying oxidative stress and aberrant redox signaling may enable control of neuroinflammation and improve patient outcomes.

Ellagic acid and allopurinol decrease H2O2 concentrations, epileptiform activity and astrogliosis after status epilepticus in the hippocampus of adult rats

Status epilepticus (SE) can result in an overproduction of hydrogen peroxide (H₂O₂), which contributes to oxidative stress and brain injury during different phases of epileptogenesis and seizures. The purpose of this study was to evaluate the effects of ellagic acid and allopurinol administered after SE on H₂O₂ concentrations, electrical activity and GFAP immunoreactivity in the hippocampus of rats evaluated on Day 18 after SE. H₂O₂ levels were measured using an online technique with high temporal resolution and simultaneous electrical activity recording. For this purpose, the lateral ventricles of male Wistar rats (200-250 g) were injected with pilocarpine (2.4 mg/2 µl) to induce SE. After SE, rats were injected with ellagic acid (50 mg/kg i.p., and two additional doses at 24 and 48 h) or allopurinol (50 mg/kg i.p., single dose). Administration of ellagic acid or allopurinol after SE significantly reduced the H₂O₂ concentrations and decreased the presence of epileptiform activity and GFAP immunoreactivity in the hippocampus 18 days after SE. In conclusion, the administration of antioxidants potentially reduces oxidative stress, which indicates the possible attenuation of the neurobiological consequences after SE.

Pathological Targets for Treating Temporal Lobe Epilepsy: Discoveries From Microscale to Macroscale

Temporal lobe epilepsy (TLE) is one of the most common and severe types of epilepsy, characterized by intractable, recurrent, and pharmacoresistant seizures. Histopathology of TLE is mostly investigated through observing hippocampal sclerosis (HS) in adults, which provides a robust means to analyze the related histopathological lesions. However, most pathological processes underlying the formation of these lesions remain elusive, as they are difficult to detect and observe. In recent years, significant efforts have been put in elucidating the pathophysiological pathways contributing to TLE epileptogenesis. In this review, we aimed to address the new and unrecognized neuropathological discoveries within the last 5 years, focusing on gene expression (miRNA and DNA methylation), neuronal peptides (neuropeptide Y), cellular metabolism (mitochondria and ion transport), cellular structure (microtubule and extracellular matrix), and tissue-level abnormalities (enlarged amygdala). Herein, we describe a range of biochemical mechanisms and their implication for epileptogenesis. Furthermore, we discuss their potential role as a target for TLE prevention and treatment. This review article summarizes the latest neuropathological discoveries at the molecular, cellular, and tissue levels involving both animal and patient studies, aiming to explore epileptogenesis and highlight new potential targets in the diagnosis and treatment of TLE.

The Interconnected Mechanisms of Oxidative Stress and Neuroinflammation in Epilepsy

One of the most important characteristics of the brain compared to other organs is its elevated metabolic demand. Consequently, neurons consume high quantities of oxygen, generating significant amounts of reactive oxygen species (ROS) as a by-product. These potentially toxic molecules cause oxidative stress (OS) and are associated with many disorders of the nervous system, where pathological processes such as aberrant protein oxidation can ultimately lead to cellular dysfunction and death. Epilepsy, characterized by a long-term predisposition to epileptic seizures, is one of the most common of the neurological disorders associated with OS. Evidence shows that increased neuronal excitability—the hallmark of epilepsy—is accompanied by neuroinflammation and an excessive production of ROS; together, these factors are likely key features of seizure initiation and propagation. This review discusses the role of OS in epilepsy, its connection to neuroinflammation and the impact on synaptic function. Considering that the pharmacological treatment options for epilepsy are limited by the heterogeneity of these disorders, we also introduce the latest advances in anti-epileptic drugs (AEDs) and how they interact with OS. We conclude that OS is intertwined with numerous physiological and molecular mechanisms in epilepsy, although a causal relationship is yet to be established.

Unifying mechanism behind the onset of acquired epilepsy

Acquired epilepsy (AE) can result from a number of brain insults and neurological diseases with wide etiological diversity sharing one common outcome of brain epileptiform activity. This implies that despite their disparity, all these initiating pathologies affect the same fundamental brain functions underlying network excitability. Identifying such mechanisms and their availability as therapeutic targets would help develop an effective strategy for epileptogenesis prevention. In this opinion article, we propose that the vicious cycle of NADPH oxidase (NOX)-mediated oxidative stress and glucose hypometabolism is the underlying cause of AE, as available data reveal a critical role for both pathologies in epileptogenesis and the process of seizure initiation. Altogether, here we present a novel view on the mechanisms behind the onset of AE and identify therapeutic targets for potential clinical applications.

Zafirlukast ameliorates Docetaxel-induced activation of NOD-like receptor protein 3 (NLRP3) inflammasome, mediated by sirtuin1 (SIRT1) in hepatocytes

Docetaxel-associated liver injury has become a serious public health problem, resulting in therapy discontinuation, liver failure, and death. Zafirlukast is a typical leukotriene receptor antagonist used for prophylaxis and chronic treatment of asthma. In this study, we investigate whether treatment with Zafirlukast could alleviate Docetaxel-induced cytotoxicity in hepatocytes. Our results indicate that Zafirlukast mitigated Docetaxel-induced toxicity in LO-2 hepatocytes. Firstly, Zafirlukast reduced the production of 8-hydroxy-2p-deoxyguanosine (8-OHdG) and increased the levels of reduced glutathione (GSH) against Docetaxel. Secondly, Zafirlukast elevated the levels of mitochondrial membrane potential (ΔΨm) and adenosine triphosphate (ATP). Thirdly, Zafirlukast prevented Docetaxel-induced release of lactate dehydrogenase (LDH) and increased cell viability of LO-2 hepatocytes against Docetaxel. We also found that Zafirlukast ameliorated Docetaxel-induced apoptosis by reducing Caspase-3 and Caspase-9 activity. Mechanistically, our results demonstrate that Zafirlukast inhibited the activation of NOD-like receptor protein 3 (NLRP3), mediated by SIRT1. Based on these findings, we conclude that the administration of Zafirlukast might have a protective effect against Docetaxel-induced cytotoxicity in hepatocytes.

Induction of the Nrf2 Pathway by Sulforaphane Is Neuroprotective in a Rat Temporal Lobe Epilepsy Model

Epilepsy is a chronic disease of the brain that affects over 65 million people worldwide. Acquired epilepsy is initiated by neurological insults, such as status epilepticus, which can result in the generation of ROS and induction of oxidative stress. Suppressing oxidative stress by upregulation of the transcription factor, nuclear factor erythroid 2-related factor 2 (Nrf2) has been shown to be an effective strategy to increase endogenous antioxidant defences, including in brain diseases, and can ameliorate neuronal damage and seizure occurrence in epilepsy. Here, we aim to test the neuroprotective potential of a naturally occurring Nrf2 activator sulforaphane, in in vitro epileptiform activity model and a temporal lobe epilepsy rat model. Sulforaphane significantly decreased ROS generation during epileptiform activity, restored glutathione levels, and prevented seizure-like activity-induced neuronal cell death. When given to rats after 2 h of kainic acid-induced status epilepticus, sulforaphane significantly increased the expression of Nrf2 and related antioxidant genes, improved oxidative stress markers, and increased the total antioxidant capacity in both the plasma and hippocampus. In addition, sulforaphane significantly decreased status epilepticus-induced neuronal cell death. Our results demonstrate that Nrf2 activation following an insult to the brain exerts a neuroprotective effect by reducing neuronal death, increasing the antioxidant capacity, and thus may also modify epilepsy development.

Single-Target Versus Multi-Target Drugs Versus Combinations of Drugs With Multiple Targets: Preclinical and Clinical Evidence for the Treatment or Prevention of Epilepsy

Rationally designed multi-target drugs (also termed multimodal drugs, network therapeutics, or designed multiple ligands) have emerged as an attractive drug discovery paradigm in the last 10-20 years, as potential therapeutic solutions for diseases of complex etiology and diseases with significant drug-resistance problems. Such agents that modulate multiple targets simultaneously are developed with the aim of enhancing efficacy or improving safety relative to drugs that address only a single target or to combinations of single-target drugs. Although this strategy has been proposed for epilepsy therapy >25 years ago, to my knowledge, only one antiseizure medication (ASM), padsevonil, has been intentionally developed as a single molecular entity that could target two different mechanisms. This novel drug exhibited promising effects in numerous preclinical models of difficult-to-treat seizures. However, in a recent randomized placebo-controlled phase IIb add-on trial in treatment-resistant focal epilepsy patients, padsevonil did not separate from placebo in its primary endpoints. At about the same time, a novel ASM, cenobamate, exhibited efficacy in several randomized controlled trials in such patients that far surpassed the efficacy of any other of the newer ASMs. Yet, cenobamate was discovered purely by phenotype-based screening and its presumed dual mechanism of action was only described recently. In this review, I will survey the efficacy of single-target vs. multi-target drugs vs. combinations of drugs with multiple targets in the treatment and prevention of epilepsy. Most clinically approved ASMs already act at multiple targets, but it will be important to identify and validate new target combinations that are more effective in drug-resistant epilepsy and eventually may prevent the development or progression of epilepsy.

Seizure-mediated iron accumulation and dysregulated iron metabolism after status epilepticus and in temporal lobe epilepsy

Neuronal dysfunction due to iron accumulation in conjunction with reactive oxygen species (ROS) could represent an important, yet underappreciated, component of the epileptogenic process. However, to date, alterations in iron metabolism in the epileptogenic brain have not been addressed in detail. Iron-related neuropathology and antioxidant metabolic processes were investigated in resected brain tissue from patients with temporal lobe epilepsy and hippocampal sclerosis (TLE-HS), post-mortem brain tissue from patients who died after status epilepticus (SE) as well as brain tissue from the electrically induced SE rat model of TLE. Magnetic susceptibility of the presumed seizure-onset zone from three patients with focal epilepsy was compared during and after seizure activity. Finally, the cellular effects of iron overload were studied in vitro using an acute mouse hippocampal slice preparation and cultured human fetal astrocytes. While iron-accumulating neurons had a pyknotic morphology, astrocytes appeared to acquire iron-sequestrating capacity as indicated by prominent ferritin expression and iron retention in the hippocampus of patients with SE or TLE. Interictal to postictal comparison revealed increased magnetic susceptibility in the seizure-onset zone of epilepsy patients. Post-SE rats had consistently higher hippocampal iron levels during the acute and chronic phase (when spontaneous recurrent seizures are evident). In vitro, in acute slices that were exposed to iron, neurons readily took up iron, which was exacerbated by induced epileptiform activity. Human astrocyte cultures challenged with iron and ROS increased their antioxidant and iron-binding capacity, but simultaneously developed a pro-inflammatory phenotype upon chronic exposure. These data suggest that seizure-mediated, chronic neuronal iron uptake might play a role in neuronal dysfunction/loss in TLE-HS. On the other hand, astrocytes sequester iron, specifically in chronic epilepsy. This function might transform astrocytes into a highly resistant, pro-inflammatory phenotype potentially contributing to pro-epileptogenic inflammatory processes.

Association between the Serum Coenzyme Q10 Level and Seizure Control in Patients with Drug-Resistant Epilepsy

Drug-resistant epilepsy (DRE) is a chronic neurological disorder with somatic impacts and increased risk of metabolic comorbidities. Oxidative stress might play an important role in metabolic effects and as a regulator of seizure control, while coenzyme Q10 (CoQ10) could improve insulin sensitivity through antioxidant effects. We aimed to investigate the association between CoQ10 level and clinical outcome, represented by the seizure frequency and quality of life, in DRE patients. DRE patients (N = 33) had significantly higher serum insulin levels and lower scores on the physical domain of the World Health Organization Quality of Life questionnaire (WHOQoL) than gender-age matched controls. The serum CoQ10 level (2910.4 ± 1163.7 ng/mL) was much higher in DRE patients than the normal range. Moreover, the serum CoQ10 level was significantly correlated with the seizure frequency (r = −0.412, p = 0.037) and insulin level (r = 0.409, p = 0.038). Based on stratification by insulin resistance (HOMA-IR > 2.4), the subgroup analysis showed that patients with a greater HOMA-IR had higher CoQ10 levels and lower seizure frequency, and had a significantly worse quality of life. In summary, CoQ10 could be a mediator involved in the mechanism of epilepsy and serve as a biomarker of the clinical outcome in DER patients.

Imbalance of Systemic Redox Biomarkers in Children with Epilepsy: Role of Ferroptosis

To assess if ferroptosis, a new type of programmed cell death accompanied by iron accumulation, lipid peroxidation, and glutathione depletion, occurs in children with epilepsy, and in order to identify a panel of biomarkers useful for patient stratification and innovative-targeted therapies, we measured ferroptosis biomarkers in blood from 83 unrelated children with a clinical diagnosis of epilepsy and 44 age-matched controls. We found a marked dysregulation of three ferroptosis key markers: a consistent increase of 4-hydroxy-2-nonenal (4-HNE), the main by-product of lipid peroxidation, a significant decrease of glutathione (GSH) levels, and a partial inactivation of the enzyme glutathione peroxidase 4 (GPX4), the mediator of lipid peroxides detoxification. Furthermore, we found a significant increase of NAPDH oxidase 2 (NOX2) in the blood of children, supporting this enzyme as a primary source of reactive oxygen species (ROS) in epilepsy. Additionally, since the nuclear factor erythroid 2-related factor 2 (NRF2) induction protects the brain from epileptic seizure damage, we also evaluated the NRF2 expression in the blood of children. The antioxidant and anti-inflammatory transcription factor was activated in patients, although not enough to re-establish a correct redox homeostasis for counteracting ferroptosis. Ferroptosis-mediated oxidative damage has been proposed as an emergent mechanism underlying the pathogenesis of epilepsy. Overall, our study confirms a crucial role for ferroptosis in epilepsy, leading to the identification of a panel of biomarkers useful to find new therapeutic targets. Developing innovative drugs, which act by inhibiting the ferroptosis signaling axis, may represent a promising strategy for new anti-seizure medications.

Anti-seizure effects of walnut peptides in mouse models of induced seizure: The involvement of GABA and nitric oxide pathways

Epilepsy is one of the foremost medical disorders. Oxidative stress is a well-known mechanism in epileptogenesis, and many studies suggest that oxidative stress affects the onset and evolution of epilepsy. Here we evaluated the walnut peptide extracts' anti-seizure property in three different mouse seizure models including pentylenetetrazole-induced clonic seizure, chemical kindling, and maximal electroshock. Walnut peptides (20 mg/Kg) were administered by intraperitoneal (IP) injection of mice 60 min before seizure induction in the three models. To delineate the mechanisms of walnut peptides anti-seizure activity, we evaluated the impact of diazepam, flumazenil, and a NOS inhibitor on this activity. Intraperitoneal administration of walnut peptides significantly increased the seizure threshold. Our results also demonstrated that walnut peptides exert their anti-seizure properties through the modulation of benzodiazepine receptors. Thus, walnut peptides may be considered as a new anti-convulsion agent, which can reduce seizure occurrence and slow down seizure progression.

Ferroptosis and Its Role in Epilepsy

Epilepsy is one of the most common symptoms of many neurological disorders. The typical excessive, synchronous and aberrant firing of neurons originating from different cerebral areas cause spontaneous recurrent epileptic seizures. Prolonged epilepsy can lead to neuronal damage and cell death. The mechanisms underlying epileptic pathogenesis and neuronal death remain unclear. Ferroptosis is a newly defined form of regulated cell death that is characterized by the overload of intracellular iron ions, leading to the accumulation of lethal lipid-based reactive oxygen species (ROS). To date, studies have mainly focused on its role in tumors and various neurological disorders, including epilepsy. Current research shows that inhibition of ferroptosis is likely to be an effective therapeutic approach for epilepsy. In this review, we outline the pathogenesis of ferroptosis, regulatory mechanisms of ferroptosis, related regulatory molecules, and their effects on epilepsy, providing a new direction for discovering new therapeutic targets in epilepsy.

Succinate accumulation contributes to oxidative stress and iron accumulation in pentylenetetrazol-induced epileptogenesis and kainic acid-induced seizure

This study explored the role of succinate accumulation in the oxidative stress and iron accumulation in both pentylenetetrazol (PTZ)-induced epileptogenesis and kainic acid (KA)-induced status epilepticus (SE). The levels of succinate, oxidative stress, iron content, iron-related protein expression, and the severity of neuronal injury and seizures were measured in both models. We found that increased concentrations of succinate were associated with increased levels of oxidative stress, iron content, iron regulator protein, and iron importer divalent metal transporter 1, as well as decreased levels of iron exporter ferropotin 1. Aggravated neuronal injury was observed in the hippocampi and cortices of both models. The cell-permeable molecule dimethyl malonate (DM), a competitive inhibitor of succinate dehydrogenase (SDH), significantly attenuated succinate accumulation, reduced the oxidative stress and iron levels, and mitigated the severity of the seizures and neuronal injury. Our results thus indicate that the accumulation of succinate due to the reverse catalysis of SDH may exacerbate oxidative stress and thus induce iron accumulation and neuronal injury in both models. Targeting succinate accumulation may achieve neuroprotective and anti-seizure effects.

New approaches for developing multi-targeted drug combinations for disease modification of complex brain disorders. Does epilepsy prevention become a realistic goal?

Over decades, the prevailing standard in drug discovery was the concept of designing highly selective compounds that act on individual drug targets. However, more recently, multi-target and combinatorial drug therapies have become an important treatment modality in complex diseases, including neurodegenerative diseases such as Alzheimer's and Parkinson's disease. The development of such network-based approaches is facilitated by the significant advance in our understanding of the pathophysiological processes in these and other complex brain diseases and the adoption of modern computational approaches in drug discovery and repurposing. However, although drug combination therapy has become an effective means for the symptomatic treatment of many complex diseases, the holy grail of identifying clinically effective disease-modifying treatments for neurodegenerative and other brain diseases remains elusive. Thus, despite extensive research, there remains an urgent need for novel treatments that will modify the progression of the disease or prevent its development in patients at risk. Here we discuss recent approaches with a focus on multi-targeted drug combinations for prevention or modification of epilepsy. Over the last ~10 years, several novel promising multi-targeted therapeutic approaches have been identified in animal models. We envision that synergistic combinations of repurposed drugs as presented in this review will be demonstrated to prevent epilepsy in patients at risk within the next 5-10 years.

Progress on mitochondrial silence information regulator family in epilepsy

SIRT3, SIRT4 and SIRT5 are located in mitochondria and also known as mitochondrial sirtuins. They play important roles in regulating many cellular functions including cell survival, cell cycle or apoptosis, DNA repair and metabolism. Mitochondrial sirtuins are involved in the protection of mitochondrial integrity and energy metabolism under stress regulating the expression of neurotransmitter receptors, neurotrophins, extracellular matrix proteins and various transcription factors, thus involved in epileptogenesis triggered by both genetic or acquired factors. Here we review research progress on the actions of mitochondrial sirtuin in epilepsy; and discuss the challenges and perspectives of mitochondrial sirtuin as a potential therapeutic target for epilepsy.

The protective effect of hydroxylated fullerene pretreatment on pilocarpine-induced status epilepticus

Status epilepticus (SE) is a neurological emergency. The pathological hallmark of neuronal damage after epileptic seizures could be the chain reaction of oxygen free radicals. Hydroxylated fullerenes (HFs) are novel and effective free radical scavengers, which play an important role in various neurological diseases. However, whether they have a protective effect against epileptic seizures remains elusive. Our study explores the effect of pretreatment with HFs in different doses (0.5, 5, and 10 mg/kg) on SEmodels induced by pilocarpine (PILO). The results suggest that HFs have a protective effect on SE in a dose-dependent manner. HFs significantly reduce the incidence of SE, prolong the latency to SE, reduce the malondialdehyde (MDA) levels, and increase the glutathione (GSH) and superoxide dismutase (SOD) levels. In addition, HFs significantly raise the expression of B-cell lymphoma-2 (Bcl-2) and reduce the expression of Bcl-2-associated X protein (Bax). We found that expressions of nuclear NF-E2-related factor 2 (nNrf2), heme oxygenase-1 (HO-1) and NADPH: quinone oxidoreductase-1 (NQO1) were upregulated 24 h after the onset of SE, but the increase was not enough to combat oxidative stress damage, nor to attenuate lipid peroxidation and apoptosis. The expressions of these proteins in HFs pretreatment groups increased more significantly than those in the epilepsy (EP) group, which effectively reduced lipid peroxidation and apoptosis in the hippocampus. In summary, these findings highlight that HFs pretreatment has a protective effect against PILO-induced SE in rats. It may relieve oxidative stress damage by activating the Nrf2-ARE signaling pathway. It provides evidence that fullerene derivatives may have therapeutic potential for epileptic seizures.

Inhibitors of Src Family Kinases, Inducible Nitric Oxide Synthase, and NADPH Oxidase as Potential CNS Drug Targets for Neurological Diseases

Neurological diseases share common neuroinflammatory and oxidative stress pathways. Both phenotypic and molecular changes in microglia, astrocytes, and neurons contribute to the progression of disease and present potential targets for disease modification. Src family kinases (SFKs) are present in both neurons and glial cells and are upregulated following neurological insults in both human and animal models. In neurons, SFKs interact with post-synaptic protein domains to mediate hyperexcitability and neurotoxicity. SFKs are upstream of signaling cascades that lead to the modulation of neurotransmitter receptors and the transcription of pro-inflammatory cytokines as well as producers of free radicals through the activation of glia. Inducible nitric oxide synthase (iNOS/NOS-II) and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2), the major mediators of reactive nitrogen/oxygen species (RNS/ROS) production in the brain, are also upregulated along with the pro-inflammatory cytokines following neurological insult and contribute to disease progression. Persistent neuronal hyperexcitability, RNS/ROS, and cytokines can exacerbate neurodegeneration, a common pathognomonic feature of the most prevalent neurological disorders such as Alzheimer's disease, Parkinson's disease, and epilepsy. Using a wide variety of preclinical disease models, inhibitors of the SFK-iNOS-NOX2 signaling axis have been tested to cure or modify disease progression. In this review, we discuss the SFK-iNOS-NOX2 signaling pathway and their inhibitors as potential CNS targets for major neurological diseases.

Antioxidants Targeting Mitochondrial Oxidative Stress: Promising Neuroprotectants for Epilepsy

Mitochondria are major sources of reactive oxygen species (ROS) within the cell and are especially vulnerable to oxidative stress. Oxidative damage to mitochondria results in disrupted mitochondrial function and cell death signaling, finally triggering diverse pathologies such as epilepsy, a common neurological disease characterized with aberrant electrical brain activity. Antioxidants are considered as promising neuroprotective strategies for epileptic condition via combating the deleterious effects of excessive ROS production in mitochondria. In this review, we provide a brief discussion of the role of mitochondrial oxidative stress in the pathophysiology of epilepsy and evidences that support neuroprotective roles of antioxidants targeting mitochondrial oxidative stress including mitochondria-targeted antioxidants, polyphenols, vitamins, thiols, and nuclear factor E2-related factor 2 (Nrf2) activators in epilepsy. We point out these antioxidative compounds as effectively protective approaches for improving prognosis. In addition, we specially propose that these antioxidants exert neuroprotection against epileptic impairment possibly by modulating cell death interactions, notably autophagy-apoptosis, and autophagy-ferroptosis crosstalk.

Rosiglitazone Prevents Autophagy by Regulating Nrf2-Antioxidant Response Element in a Rat Model of Lithium-pilocarpine-induced Status Epilepticus

Status epilepticus (SE) leads to irreversible neuronal damage and consists of a complex pathogenesis that involves oxidative stress and subsequent autophagy. Rosiglitazone has recently been considered as a potential neuroprotective factor in epilepsy because of its antioxidative function. The aim of this study was to assess the effects of rosiglitazone in SE rat models and investigate whether its mechanisms of action involve autophagy via the antioxidant factor, nuclear factor erythroid 2-related factor 2 (Nrf2). The male Sprague-Dawley rats (200-220 g) were used to establish lithium-pilocarpine-induced SE model. We found that rosiglitazone markedly improved neuronal survival at 24-h post-SE as indicated via Hematoxylin-Eosin and Nissl staining. Furthermore, along with a reduction in reactive oxygen species, rosiglitazone pretreatment enhanced the antioxidative activity of superoxide dismutase and the expression level of Nrf2, as detected via chemical assay kits and Western blotting, respectively. In addition, the microtubule-associated protein light chain 3II (LC3II)/LC3I ratio was increased and peaked at 24 h after SE, whereas p62 mRNA levels were sharply elevated at 72 h after SE, both SE-induced increases of which were reversed via rosiglitazone pretreatment. To further test our hypothesis of the key role of Nrf2 in this process, small-interfering RNA for Nrf2 (siNrf2) was then transfected into SE rats to knockdown Nrf2 expression. We found that siNrf2 partially blocked the above effects of rosiglitazone on autophagy-related proteins in SE rats. Taken together, our findings suggest that rosiglitazone attenuates oxidative-stress-induced autophagy via increasing Nrf2 in SE rats and may be used as a promising therapeutic strategy for SE treatment.

Diapocynin, an NADPH oxidase inhibitor, counteracts diisopropylfluorophosphate-induced long-term neurotoxicity in the rat model

Organophosphate (OP) nerve agents are a threat to both the military and civilians. OP exposure causes cholinergic crisis and status epilepticus (SE) because of irreversible inhibition of acetylcholinesterase that can be life-threatening if left untreated. OP survivors develop long-term morbidity, such as cognitive impairment and motor dysfunction, because of oxidative stress and progressive neuroinflammation and neurodegeneration, which act as disease promoters. Current medical countermeasures (MCMs) do not mitigate these pathologies. Therefore, our goal was to target these disease promoters using diapocynin (DPO), an NADPH oxidase inhibitor, in addition to MCMs, in a rat diisopropylfluorophosphate (DFP) model. The DFP-intoxicated rats were treated with DPO (300 mg/kg, oral, six doses, 12-h intervals) or vehicle 2 h following behavioral SE termination with diazepam. The DPO treatment significantly rescued DFP-induced motor impairment and attenuated epileptiform spiking during the first 72 h after DFP exposure in severely seizing rats despite no difference in epileptiform spike rate between the vehicle and DPO groups in mild SE rats. DPO significantly reduced DFP-induced reactive astrogliosis, neurodegeneration, GP91phox , glutathiolated protein, serum nitrite, and proinflammatory cytokines and chemokines, such as interleukins (ILs) IL-1α, IL-6, IL-2, IL-17A, leptin, and IP-10, in the hippocampus. Collectively, these data support a neuroprotective role of DPO in an OP-induced neurotoxicity model.

Ketogenic diet, neuroprotection, and antiepileptogenesis

High fat, low carbohydrate ketogenic diets (KD) have been in use for the treatment of epilepsy for almost a hundred years. Remarkably, seizures that are resistant to conventional anti-seizure drugs can in many cases be controlled by the KD therapy, and it has been shown that many patients with epilepsy become seizure free even after discontinuation of the diet. These findings suggest that KD combine anti-seizure effects with disease modifying effects. In addition to the treatment of epilepsy, KDs are now widely used for the treatment of a wide range of conditions including weight reduction, diabetes, and cancer. The reason for the success of metabolic therapies is based on the synergism of at least a dozen different mechanisms through which KDs provide beneficial activities. Among the newest findings are epigenetic mechanisms (DNA methylation and histone acetylation) through which KD exerts long-lasting disease modifying effects. Here we review mechanisms through which KD can affect neuroprotection in the brain, and how a combination of those mechanisms with epigenetic alterations can attenuate and possibly reverse the development of epilepsy.

Seizure-Induced Oxidative Stress in Status Epilepticus: Is Antioxidant Beneficial?

Epilepsy is a common neurological disorder which affects patients physically and mentally and causes a real burden for the patient, family and society both medically and economically. Currently, more than one-third of epilepsy patients are still under unsatisfied control, even with new anticonvulsants. Other measures may be added to those with drug-resistant epilepsy. Excessive neuronal synchronization is the hallmark of epileptic activity and prolonged epileptic discharges such as in status epilepticus can lead to various cellular events and result in neuronal damage or death. Unbalanced oxidative status is one of the early cellular events and a critical factor to determine the fate of neurons in epilepsy. To counteract excessive oxidative damage through exogenous antioxidant supplements or induction of endogenous antioxidative capability may be a reasonable approach for current anticonvulsant therapy. In this article, we will introduce the critical roles of oxidative stress and further discuss the potential use of antioxidants in this devastating disease.

Proceedings of the 15th Antiepileptic Drug and Device Trials Meeting: State of the Science

On May 22-24, 2019, the 15th Antiepileptic Drug and Device (AEDD) Trials Conference was held, which focused on current issues related to AEDD development from preclinical models to clinical prognostication. The conference featured regulatory agencies, academic laboratories, and healthcare companies involved in emerging epilepsy therapies and research. The program included discussions around funding and support for investigations in epilepsy and neurologic research, clinical trial design and integrated outcome measures for people with epilepsy, and drug development and upcoming disease-modifying therapies. Finally, the conference included updates from the preclinical, clinical, and device pipeline. Summaries of the talks are provided in this paper, with the various pipeline therapeutics in the listed tables to be outlined in a subsequent publication.

Anxiety Therapeutic Interventions of β-Caryophyllene: A Laboratory-Based Study

The bicyclic sesquiterpene β-caryophyllene (BCP) has diverse biological activities, including antioxidant, anti-inflammatory, antidiabetic, and analgesic effects. This study evaluates anxiolytic, toxicity, and antioxidant effects of BCP using in vitro and in vivo test models. The anxiolytic effects were tested in Swiss albino mice ( Mus musculus) by applying the elevated plus-maze, rota-rod, light and dark, and hiding sphere models, while the toxicity was evaluated by brine shrimp ( Artemia salina) lethality bioassay. Additionally, the antioxidant capacity was tested by using 2,2-diphenyl-1-picrylhydrazyl radical, 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid hydroxyl radical scavenging, and the Saccharomyces cerevisiae test model. The results suggest that BCP exerted a dose-dependent anxiolytic-like effect on the experimental animals. It did not show toxicity in A. salina at 24 hours. BCP showed a concentration-dependent free-radical-scavenging capacity, similar to the standard antioxidant Trolox. It also showed protective and repair capacities against hydrogen peroxide-induced damaging effects in isogenic and wild-type S. cerevisiae strains. Taken together, BCP exerted antioxidant and protective effects, which can be targeted to treat neurological diseases and disorders such as anxiety.