Evaluation of the Influence of Antiepileptic Therapy on Antioxidant Enzyme Activity and Lipid Peroxidation in Erythrocytes of Children With Epilepsy

Upregulation of ACSL, ND75, Vha26 and sesB genes by antiepileptic drugs resulted in genotoxicity in drosophila

Clobazam (CLB) and Vigabatrin (VGB) are commonly used antiepileptic drugs (AEDs) in the treatment of epilepsy. Here, we have examined the genotoxic effect of these AEDs in Drosophila melanogaster. The Drosophila larvae were exposed to different concentrations of CLB and VGB containing food media. The assessment encompassed oxidative stress, DNA damage, protein levels, and gene expression profiles. In the CLB-treated group, a reduction in reactive oxygen species (ROS) and lipid peroxidation (LPO) levels was observed, alongside increased levels of superoxide dismutase (SOD), catalase (CAT), and nitric oxide (NO). Conversely, the VGB-treated group displayed contrasting results, with increased ROS and LPO and decreased SOD, CAT, and NO levels. However, both CLB and VGB induced DNA damage in Drosophila. Proteomic analysis (SDS-PAGE and OHRLCMS) in the CLB and VGB groups identified numerous proteins, including Acyl-CoA synthetase long-chain, NADH-ubiquinone oxidoreductase 75 kDa subunit, V-type proton ATPase subunit E, ADP/ATP carrier protein, malic enzyme, and DNA-binding protein modulo. These proteins were found to be associated with pathways like growth promotion, notch signaling, Wnt signaling, neuromuscular junction (NMJ) signaling, bone morphogenetic protein (BMP) signaling, and other GABAergic mechanisms. Furthermore, mRNA levels of ACSL, ND75, Vha26, sesB, and Men genes were upregulated in both CLB and VGB-treated groups. These findings suggest that CLB and VGB could have the potential to induce genotoxicity and post-transcriptional modifications in humans, highlighting the importance of monitoring their effects when used as AEDs.

A Cross-Sectional Study Comparing Oxidative Stress in Patients with Epilepsy Treated with Old and New Generation Antiseizure Medications

Background and Objectives: Oxidative stress resulting from a disturbance of the endogenous redox system is suspected in numerous diseases of the central nervous system, including epilepsy. In addition, antiseizure medications (ASMs), especially those of the old generation, may further increase oxidative stress. To evaluate the effects of ASM generation on oxidative stress, we conducted a cross-sectional study in patients with epilepsy treated with old, new, and polytherapy. Materials and Methods: The antioxidant activity of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase, as well as the concentrations of malondialdehyde, protein carbonyl, nitrate, nitrite, and glutathione in reduced and oxidized forms, were measured in 49 patients with epilepsy and 14 healthy controls. In addition, the plasma concentrations of ASMs and metabolites of carbamazepine and valproic acid were measured in the patients. Results: Patients with epilepsy showed increased activities of superoxide dismutase and catalase (p < 0.001), concentrations of glutathione disulfide and markers of nitric oxide metabolism (p < 0.001), and decreased activities of glutathione peroxidase, glutathione reductase, glutathione, and nitrite concentrations (p ≤ 0.005) compared to healthy controls. A comparison of ASM generations revealed increased levels of superoxide dismutase and catalase (p ≤ 0.007) and decreased levels of glutathione peroxidase and glutathione reductase (p ≤ 0.01) in patients treated with old ASMs compared to those treated with new generation ASMs. In addition, an increase in protein carbonyl and nitric oxide metabolites (p ≤ 0.002) was observed in patients treated with old generation ASMs compared to those treated with new generation ASMs. Most oxidative stress parameters in patients receiving polytherapy with ASMs were intermediate between the results of patients treated with the old and new generations of ASMs. Conclusions: An increase in oxidative stress markers and modulation of antioxidant enzyme activities was observed in patients with epilepsy compared to controls. The results of our study showed significantly higher oxidative stress in patients treated with old ASMs compared to those treated with new generation ASMs.

Evaluation of oxidative stress and its association with drug therapy in inpatients treated for cocaine dependence

The use of cocaine affects several systems and organs of the human body and the consumption of this substance leads to an increase in the production of reactive oxygen species, and to the reduction of antioxidant defenses. The aim of this study was to evaluate the oxidative stress (OS), biochemical and hematological parameters in patients hospitalized for treatment of cocaine addiction, comparing levels at hospital admission and discharge. Forty patients were included in the study. OS was evaluated using catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GPx), total antioxidant power (FRAP), malondialdehyde (MDA), and sulfhydryl group (GS). The medications used during hospitalization were registered and their influence on the parameters of OS was analyzed. After the hospitalization period, there was an increase in GGT levels, a reduction in SOD activity, and an increase in GPx activity and FRAP levels. Carbamazepine users had higher SOD values and lower FRAP values at hospital discharge. The use of chlorpromazine caused differences in creatinine and gamma-glutamyltransferase (GGT) serum leves, and the levels of glutamic oxalacetic transaminase (TGO), MDA, and FRAP were increased at hospital discharge. Haloperidol and thiamine during hospitalization interfered with alkaline phosphatase levels. The use of risperidone caused an increase in the levels of SOD, and folic acid use was associated with lower levels of GPx and higher levels of glutamic-pyruvic transaminase (TGP) and alkaline phosphatase. Drug rehabilitation treatment was effective in decreasing oxidative damage represented by the reduction of biological markers.

Increased levels of lipid and protein oxidation in rat prefrontal cortex after treatment by lithium, valproic acid, and olanzapine

Oxidative stress is widely accepted to contribute to the pathogenesis of several psychiatric diseases. Many antipsychotic drugs and mood stabilizers act through restoration of the dysregulated oxidative homeostasis in the brain. However, the long-term effect of these drugs per se in terms of their potential to interfere with the oxidative status in the brain remains largely controversial. The present study aimed to investigate the sole effect of three commonly used psychoactive drugs, lithium, valproic acid, and olanzapine, on lipid and protein oxidation status in the prefrontal cortex of healthy rats. A total of 80 adult male albino Wistar rats were used, and groups were treated with saline (control), lithium, valproic acid, or olanzapine daily for 30 days. Following sacrification, right prefrontal cortexes were dissected and homogenized. Lipid peroxidation (LPO) and protein oxidation (AOPP) assays were performed by ELISA. LPO levels were significantly higher in lithium and valproic acid-treated rats by 45% and 40%, respectively. Olanzapine treatment caused a mild 26% increase in LPO levels, but the effect was non-significant. Lithium, valproic acid, and olanzapine treatments significantly increased AOPP levels by 58%, 54%, and 36.5%, respectively. There was a strong positive correlation between the lipid peroxidation and protein oxidation levels. Our results call attention to the need to consider the pro-oxidative capacity of antipsychotic drugs per se and their potential to disturb the oxidative homeostasis in the brain during long-term medication for psychiatric diseases.

The effects of regular swimming exercise during sodium valproate treatment on seizure behaviors and EEG recordings in pentylenetetrazole-kindled rats

We investigated the effects of alone/combined regular swimming exercise and sodium valproate on epileptic seizure behaviors and EEG recordings, anti-oxidative mechanism, learning, and memory in pentylenetetrazole (PTZ)-kindled rats. Forty-eight healthy rats were randomly divided into eight equal groups as control (CONT), swimming exercise (EX), sodium valproate (SV), SV+EX, PTZ, EX+PTZ, SV+PTZ and SV+EX+PTZ. The rats were forced to regular swimming exercise for 60 min every other day, 13 doses of PTZ (40 mg/kg) were given to induce epileptic seizures and 200 mg/kg SV was given for 28 days. Epileptic seizures were evaluated by visual observation and EEG recordings (total spike numbers and number of epileptiform discharges). Memory and learning skills were assessed with passive avoidance test. According to our visual seizure observations, seizure latency was prolonged only in SV+EX+PTZ (p < 0.001) group, seizure severity score decreased in SV+PTZ (p < 0.05) and SV+EX+PTZ (p < 0.001) groups and seizure frequency was reduced in SV+PTZ (p < 0,001), EX+PTZ (p < 0,001), and SV+EX+PTZ (p < 0,001) groups. Total spike numbers and number of epileptiform discharges highly increased in PTZ group, whereas they decreased in swimming exercise and/or SV treatment groups. The most effective result was seen in the combined therapy group. Memory deficit was observed in PTZ -kindling group, but it didn't change with exercise or SV. Based on our results, regular swimming exercise had positive effects on PTZ-induced seizure frequency, and combined therapy of regular swimming exercise and SV is the most effective way to ameliorate visual seizure behaviors and decrease spike numbers and number of epileptiform discharges according to EEG recordings. Regular swimming exercise could be an alternative option to reduce the dose of SV and the side effects of SV can be avoided in clinical aspects.

Effect of antiepileptic drug (Topiramate) and cold pressed ginger oil on testicular genes expression, sexual hormones and histopathological alterations in mice

Sexual dysfunction in the epileptic patient is difficult to confirm whether it is ailment or therapy related. Antiepileptic drugs often use in reproductive age, through reproductive progress and maturation. On the other side, cold-pressed oils are rich in bioactive phytochemicals with health-promoting traits. The target of this work was to appraise the sexual dysfunction of antiepileptic Topiramate (TPM) and cold pressed ginger oil (CPGO) as antiepileptic alternative medicine in male mice. Fifty-four adult male albino mice were divided into nine groups (n = 6 mice). One group given saline and used as negative control; another one was given corn oil as vehicle. Six groups administered orally with TPM or CPGO at 100, 200 and 400 mg/kg. Moreover, group of animals co-administrated orally CPGO with TPM (400 mg/kg) to study their interaction. Fatty acid profile and tocols composition of CPGO were determined. in vitro assays were undertaken to evaluate radical scavenging traits of CPGO utilizing sable 1,1-diphenyl-2-picrylhydrazyl (DPPH·) and galvinoxyl radicals. The study investigated antioxidant and oxidative stress markers, sexual hormones levels, mRNA levels of vascular endothelial growth factor (Vegfa), synaptonemal complex protein (Sycp3), Wilms tumor gene (Wt1) as well as histopathological and immunohistochemical examination. Strong radical scavenging potential of CPGO against stable DPPH· and galvinoxyl radicals was recorded. The results revealed that TPM caused a dose-dependent reduction in the antioxidant activities and testosterone content, while, malonaldehyde (MDA) and nitric oxide (NO) as oxidative stress markers were elevated. Vegfa and Sycp3 mRNA expression down-regulated at all Topiramate tested doses, but Wt1 up-regulated at 400 mg/kg. TPM (400 mg/kg) revealed histological alterations associated with strong positive Bax immune reactive spermatogoneal and Leydig cells. Ginger oil elevated the CAT and SOD (antioxidant enzymes), serum testosterone and diminished the oxidative stress, up regulated the expression of Vegfa and Sycp3 and down-regulated the Wt1 expression. Meanwhile, CPGO revealed no histopathological alterations and no Bax immune-reactive cells. CPGO co-administration with TPM (400 mg/kg) attenuated the TPM toxicity. High doses of TPM may exhibit sexual dysfunction but CPGO is safe and has androgenic property. CPGO co-administration could protect the antiepileptic patient from the TPM sexual dysfunction.

Effects of Valproate Monotherapy on the Oxidant-Antioxidant Status in Mexican Epileptic Children: A Longitudinal Study

Epilepsy is a neurological disorder that can produce brain injury and neuronal death. Several factors such as oxidative stress have been implicated in epileptogenesis. Valproic acid (VPA) is a widely used drug for the treatment of epilepsy, but the mechanisms underlying these benefits are complex and still not fully understood. The objective of this study was to evaluate, for the first time, the effects of VPA on the oxidant-antioxidant status in Mexican epileptic children before and after 6 or 12 months of treatment with VPA by determining the activities of several plasmatic antioxidant enzymes (glutathione reductase (GR), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT)) and oxidant marker (malondialdehyde (MDA), hydrogen peroxide (H2O2), 8-hydroxy-2-deoxyguanosine (8-OHdG), and 3-nitrotyrosine (3-NT) levels) profiles. The possible relationships between these markers and some clinicopathological factors were also evaluated. Plasma samples were obtained from the peripheral blood of 16 healthy children and 32 patients diagnosed with epilepsy, and antioxidant/oxidant markers were measured spectrometrically. Significant decreases in all antioxidant enzyme activities, with the exception of GPx, and increases in all oxidant markers in epileptic subjects versus healthy children were observed. Interestingly, all these effects reverted after VPA monotherapy, although the results were different depending on the treatment period (6 or 12 months). These changes were contingent upon brain imaging findings, type of epilepsy, etiology of epilepsy, and the efficacy of 6 months of VPA monotherapy. Significant and positive correlations of GPx and SOD activities and H2O2 and 8-OHdG levels with the age of children at the beginning of treatment were observed. H2O2 levels were also positively correlated with number of seizures before VPA monotherapy. VPA showed significant antioxidant effects decreasing seizure activity, possibly depending on the presence of cerebral structural alterations, treatment time, and age.

Sleem A, Abd El Baset Mohamed Sayed M, A. Khadrawy Y, A. Morsy F. Cannabis sativa Increases Seizure Severity and Brain Lipid Peroxidation in Pentylenetetrazole-Induced Kindling in Rats

The effect of Cannabis sativa extract on chemical kindling induced in rats by the repeated intraperitoneal (ip) injections of pentylenetetrazole (PTZ) was studied. Rats were treated with PTZ (35 mg/kg) once every 48 hours for 12 times alone or with ip Cannabis sativa (20 mg/kg expressed as Δ9-THC content) 30 min prior to PTZ injection. Seizures were recorded for 20 minutes. Control rats received ip saline. Cannabis treatment caused significant elevation of mean seizure score as compared to PTZ only group after the 5th, 6th and 7th PTZ repeated injections during seizure development. In particular, cannabis caused significant elevation in the frequency of myoclonic jerks, rearing (stage 3), turn over onto one side position and back position (stage 4), and generalized tonic-clonic seizures (stage 5) compared with the PTZ only group. PTZ caused significant elevations in brain lipid peroxidation (malondialdehyde), and nitric oxide along with deceased reduced glutathione level. In addition, brain acetylcholinesterase (AChE) activity significantly decreased compared to control value after PTZ treatment. Cannabis given to PTZ treated rats caused significant increase in brain malondialdehyde and AChE activity compared to PTZ only group. Reduced glutathione level was restored by cannabis. Histopathological studies indicated the presence of spongiform changes, degenerated and necrotic neurons, inflammatory cells, and gliosis in cerebral cortex and degeneration of some Purkinje cells in the cerebellum in both PTZ- and cannabis-PTZ-treated groups. It is concluded that in an epilepsy model induced by repeated PTZ administration, cannabis increased lipid peroxidation and mean seizure score.

Involvement of AMPA/kainate and GABAA receptors in topiramate neuroprotective effects against methylphenidate abuse sequels involving oxidative stress and inflammation in rat isolated hippocampus

Abuses of methylphenidate (MPH) as psychostimulant cause neural damage of brain cells. Neuroprotective properties of topiramate (TPM) have been indicated in several studies but its exact mechanism of action remains unclear. The current study evaluates protective role of various doses of TPM and its mechanism of action in MPH induced oxidative stress and inflammation. The neuroprotective effects of various doses of TPM against MPH induced oxidative stress and inflammation were evaluated and then the action of TPM was studied in presence of domoic acid (DOM), as AMPA/kainate receptor agonist and bicuculline (BIC) as GABAA receptor antagonist, in isolated rat hippocampus. Open Field Test (OFT) was used to investigate motor activity changes. Oxidative, antioxidant and inflammatory factors were measured in isolated hippocampus. TPM (70 and 100mg/kg) decreased MPH induced motor activity disturbances and inhibit MPH induced oxidative stress and inflammation. On the other hand pretreatment of animals with DOM or BIC, inhibit this effect of TPM and potentiate MPH induced motor activity disturbances and increased lipid peroxidation, mitochondrial oxidized form of glutathione (GSSG) level, interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in isolated hippocampal cells and decreased reduced form of glutathione (GSH) level, superoxide dismutase, glutathione peroxidase and glutathione reductase activity. It seems that TPM can protect cells of hippocampus from oxidative stress and neuroinflammation and it could be partly by activation of GABAA receptor and inhibition of AMPA/kainite receptor.

Exploring the possible link between MeCP2 and oxidative stress in Rett syndrome

Rett syndrome (RTT, MIM 312750) is a rare and orphan progressive neurodevelopmental disorder affecting girls almost exclusively, with a frequency of 1/15,000 live births of girls. The disease is characterized by a period of 6 to 18 months of apparently normal neurodevelopment, followed by early neurological regression, with a progressive loss of acquired cognitive, social, and motor skills. RTT is known to be caused in 95% of the cases by sporadic de novo loss-of-function mutations in the X-linked methyl-CpG-binding protein 2 (MECP2) gene encoding methyl-CpG binding protein 2 (MeCP2), a nuclear protein able to regulate gene expression. Despite almost two decades of research into the functions and role of MeCP2, little is known about the mechanisms leading from MECP2 mutation to the disease. Oxidative stress (OS) is involved in the pathogenic mechanisms of several neurodevelopmental and neurodegenerative disorders, although in many cases it is not clear whether OS is a cause or a consequence of the pathology. Fairly recently, the presence of a systemic OS has been demonstrated in RTT patients with a strong correlation with the patients' clinical status. The link between MECP2 mutation and the redox imbalance found in RTT is not clear. Animal studies have suggested a possible direct correlation between Mecp2 mutation and increased OS levels. In addition, the restoration of Mecp2 function in astrocytes significantly improves the developmental outcome of Mecp2-null mice and reexpression of Mecp2 gene in the brain of null mice restored oxidative damage, suggesting that Mecp2 loss of function can be involved in oxidative brain damage. Starting from the evidence that oxidative damage in the brain of Mecp2-null mice precedes the onset of symptoms, we evaluated whether, based on the current literature, the dysfunctions described in RTT could be a consequence or, in contrast, could be caused by OS. We also analyzed whether therapies that at least partially treated some RTT symptoms can play a role in defense against OS. At this stage we can propose that OS could be one of the main causes of the dysfunctions observed in RTT. In addition, the major part of the therapies recommended to alleviate RTT symptoms have been shown to interfere with oxidative homeostasis, suggesting that MeCP2 could somehow be involved in the protection of the brain from OS.

Effect of saffron (Crocus sativus L.) on sodium valporate induced cytogenetic and testicular alterations in albino rats

The present study investigated the cytogenetic and testicular damage induced by the antiepileptic drug, sodium valporate (SVP) in albino rats and the effect of saffron aqueous extracts. Treating rats with SVP caused a significant increase in the chromosomal aberrations either structural or numerical and decreased the mitotic index. Besides, animals administered SVP showed DNA damage appeared in the single strand breaks (comet assay). Testis of SVP-treated rats showed many histopathological changes. A significant decrease in seminiferous tubules and their epithelial heights diameters and inhibition of spermatogenesis was recorded. In addition, the number of sperm head abnormalities was increased. Biochemical results revealed an increase in malondialdhyde (MDA) which is lipid peroxidation marker and a significant decrease in the level of serum antioxidant enzyme, catalase (CAT) and reducing antioxidant power (RAP). Animals given SVP and saffron showed an improvement in chromosomal aberrations, mitotic index, DNA damage and testicular alterations caused by SVP. Moreover, MDA decreased and CAT and RAP increased. It is concluded from the present results that the ameliorative effects of saffron extract against SVP-induced cytogenetic and testicular damage in albino rats may be due to the presence of one or more antioxidant components of saffron.

Relationship between oxidative stress and chronic daily headache in children

The aim of this study was to investigate the relationship between oxidative stress and chronic daily headache (CDH) in children. Although there are reports that oxidative injury may play a role in the pathophysiology of some neurologic disorders, such as migraine and epilepsy, by disrupting or destroying cell membranes through the formation of free radical and reactive oxygen species, the pathophysiology of headache is not clearly established. A total of 38 children (16 boys and 22 girls) with CDH, aged between 7 and 15 years, were enrolled in the study. The control group consisted of 39 healthy children (17 boys and 22 girls), aged between 7 and 14 years. The mean age was 10.9 ± 2.2 years for both the groups. Activities of erythrocyte superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) as well as malondialdehyde (MDA) levels in all the children of both the groups were measured. Mean activities of erythrocyte SOD, CAT, and GPx as well as MDA levels were significantly higher in the study group than in the control group (p < 0.001). The findings of this study suggest that oxidative stress may play a causal or consequential role in children with CDH.

Oxidative stress-associated hypertension in surgically induced brain injury patients: effects of β-blocker and angiotensin-converting enzyme inhibitor

BACKGROUND

Postoperative hypertension is a common problem in patients undergoing surgical procedures, and the modification of this response could result in improved surgical outcome. Although it is recognized that the incidence of postoperative hypertension is higher in neurosurgical procedures, mechanisms behind this are not well understood. Oxidative stress is an important component of brain injury, and free radicals can influence blood pressure by a number of mechanisms. This study examined the effect of pretreatment with antihypertensive agents on postoperative hypertension in patients undergoing neurosurgery for supratentorial brain tumors and the role of oxidative stress in the process.

METHODS

Forty-nine consecutive patients who underwent surgery for supratentorial brain tumors were divided in to three groups (control, Tab. Glucose; atenolol; and lisinopril groups). Blood was drawn at three time points (1 d before the surgery, at the time of dura opening, and at the time of extubation). Hemodynamic parameters in all three groups and levels of malondialdehyde, protein carbonyl content, nitrate, and α-tocopherol in serum at various time points were analyzed.

RESULTS

The results showed that perioperative hemodynamic changes were highly associated with oxidative stress parameters in all the three groups. It was seen that atenolol and lisinopril significantly decreased levels of malondialdehyde, protein carbonyl content, and nitrate in the intraoperative period (P < 0.05), an effect which continued postoperatively.

CONCLUSIONS

The results demonstrate that pretreatment with β-receptor blocker (atenolol) or angiotensin-converting enzyme inhibitor (lisinopril) reduces postoperative hypertension in patients undergoing neurosurgery, and inhibition of oxidative stress may be a potential mechanism for this effect.

Oxidative stress-related biomarkers in autism: systematic review and meta-analyses

Autism spectrum disorders (ASDs) are rarely diagnosed in children younger than 2 years, because diagnosis is based entirely on behavioral tests. Oxidative damage may play a central role in this pathogenesis, together with the interconnected transmethylation cycle and transsulfuration pathway. In an attempt to clarify and quantify the relationship between oxidative stress-related blood biomarkers and ASDs, a systematic literature review was carried out. For each identified study, mean biomarker levels were compared in cases and controls providing a point estimate, the mean ratio, for each biomarker. After meta-analysis, the ASD patients showed decreased blood levels of reduced glutathione (27%), glutathione peroxidase (18%), methionine (13%), and cysteine (14%) and increased concentrations of oxidized glutathione (45%) relative to controls, whereas superoxide dismutase, homocysteine, and cystathionine showed no association with ASDs. For the C677T allele in the methylene tetrahydrofolate reductase gene (MTHFR), homozygous mutant subjects (TT) showed a meta-OR of 2.26 (95% CI 1.30-3.91) of being affected by ASD with respect to the homozygous nonmutant (CC). Case-control studies on blood levels of vitamins suggest a lack of association (folic acid and vitamin B12) or rare association (vitamins A, B6, C, D, E). Sparse results were available for other biomarkers (ceruloplasmin, catalase, cysteinylglycine, thiobarbituric acid-reactive substances, nitric oxide) and for polymorphisms in other genes. Existing evidence is heterogeneous and many studies are limited by small sample size and effects. In conclusion, existing evidence suggests a role for glutathione metabolism, the transmethylation cycle, and the transsulfuration pathway, although these findings should be interpreted with caution, and larger, more standardized studies are warranted.

Coenzyme Q10 enhances the anticonvulsant effect of phenytoin in pilocarpine-induced seizures in rats and ameliorates phenytoin-induced cognitive impairment and oxidative stress

Conventional antiepileptic drugs fail to adequately control seizures and predispose to cognitive impairment and oxidative stress with chronic usage in a significant proportion of patients with epilepsy. Coenzyme Q10 (CoQ10), an antioxidant compound, exhibits a wide range of therapeutic effects that are attributed to its potent antioxidant capacity. To evaluate the neuroprotective effects of CoQ10 in rats against the observed oxidative stress during seizures induced by pilocarpine, and to study its interactions with the conventional antiepileptic drug phenytoin, two experiments were performed. Experiment 1 was conducted to test the effect of phenytoin, CoQ10, or both on seizure severity and oxidative markers in the pilocarpine model of epilepsy. Experiment 2 was conducted to test the effect of 2 weeks of chronic treatment with phenytoin, CoQ10, or both on oxidative markers and behavioral tests in rats. Overall, CoQ10 reduced the severity of pilocarpine-induced seizures and the severity of oxidative stress. Moreover, it potentiated the antiepileptic effects afforded by phenytoin treatment, with the potential safety and efficacy in ameliorating oxidative stress and cognitive impairment caused by chronic phenytoin therapy. Our findings strongly suggest that CoQ10 can be considered a safe and effective adjuvant to phenytoin therapy in epilepsy both to ameliorate seizure severity and to protect against seizure-induced oxidative damage by reducing the cognitive impairment and oxidative stress associated with chronic use of phenytoin.

Role of oxidative stress in epileptic seizures

Oxidative stress resulting from excessive free-radical release is likely implicated in the initiation and progression of epilepsy. Therefore, antioxidant therapies aimed at reducing oxidative stress have received considerable attention in epilepsy treatment. However, much evidence suggests that oxidative stress does not always have the same pattern in all seizures models. Thus, this review provides an overview aimed at achieving a better understanding of this issue. We summarize work regarding seizure models (i.e., genetic rat models, kainic acid, pilocarpine, pentylenetetrazol, and trimethyltin), oxidative stress as an etiologic factor in epileptic seizures (i.e., impairment of antioxidant systems, mitochondrial dysfunction, involvement of redox-active metals, arachidonic acid pathway activation, and aging), and antioxidant strategies for seizure treatment. Combined, this review highlights pharmacological mechanisms associated with oxidative stress in epileptic seizures and the potential for neuroprotection in epilepsy that targets oxidative stress and is supported by effective antioxidant treatment.