Oxidative stress in patients with epilepsy is independent of antiepileptic drugs

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.

Sex Differences in Hepatic Inflammation, Lipid Metabolism, and Mitochondrial Function Following Early Lipopolysaccharide Exposure in Epileptic WAG/Rij Rats

Among the non-communicable neurological diseases, epilepsy is characterized by abnormal brain activity with several peripheral implications. The role of peripheral inflammation in the relationship between seizure development and nonalcoholic fatty liver disease based on sex difference remains still overlooked. Severe early-life infections lead to increased inflammation that can aggravate epilepsy and hepatic damage progression, both related to increased odds of hospitalization for epileptic patients with liver diseases. Here, we induced a post-natal-day 3 (PND3) infection by LPS (1 mg/kg, i.p.) to determine the hepatic damage in a genetic model of young epileptic WAG/Rij rats (PND45). We evaluated intra- and inter-gender differences in systemic and liver inflammation, hepatic lipid dysmetabolism, and oxidative damage related to mitochondrial functional impairment. First, epileptic rats exposed to LPS, regardless of gender, displayed increased serum hepatic enzymes and altered lipid profile. Endotoxin challenge triggered a more severe inflammatory and immune response in male epileptic rats, compared to females in both serum and liver, increasing pro-inflammatory cytokines and hepatic immune cell recruitment. Conversely, LPS-treated female rats showed significant alterations in systemic and hepatic lipid profiles and reduced mitochondrial fatty acid oxidation. The two different sex-dependent mechanisms of LPS-induced liver injury converge in increased ROS production and related mitochondrial oxidative damage in both sexes. Notably, a compensatory increase in antioxidant defense was evidenced only in female rats. Our study with a translational potential demonstrates, for the first time, that early post-natal infections in epileptic rats induced or worsened hepatic disorders in a sex-dependent manner, amplifying inflammation, lipid dysmetabolism, and mitochondrial impairment.

A preclinical study to determine the anti-epileptic effect of biotin on maximal electroshock (MES) and pentylenetetrazole (PTZ) models in albino rats

OBJECTIVES

Vitamin B7(biotin) is not synthesized in our body and is retrieved from some food products like eggs, liver, pork and leafy vegetables and as well as microbes of gut. Deficiency of biotin majorly leads to loss of hair, rashes over skin, lethargy and seizures. It is noted that biotin is an anti-oxidant and negates free radical effects. Biotin is also involved in carbon dioxide metabolism and it might alter seizure threshold. Studies also suggest its effect on lipid metabolism as well. So, the primary objective of this study was to assess the efficacy of biotin in maximal electric shock (MES) induced generalized tonic-clonic seizures (GTCS) and pentylenetetrazole (PTZ) induced absence seizures. The secondary objective is to study the effect of combined treatment of biotin and sodium valproate on seizures as well as plasma lipid profile in rats.

METHODS

In our study 30 albino Wistar rats each were used in MES and PTZ model respectively. 30 rats were divided equally into following groups: I - distilled water (negative control) II - distilled water (positive control) III - sodium valproate (300 mg/kg) IV - biotin (10 mg/kg/day) V - biotin (10 mg/kg) + sodium valproate (150 mg/kg).

RESULTS

We observed that the tonic hind limb extension was significantly reduced in the treatment group in MES model. Nitric oxide levels were also seen raised in combination group in MES model and all the treated groups in PTZ model. Biotin treated group showed increased high-density lipoproteins and reduced low density lipoproteins and triglycerides.

CONCLUSIONS

Biotin had an additive effect to sodium valproate in both the models of epilepsy in rats. Further, it was also able to counteract hyperlipidemia cause by sodium valproate.

Determination of oxidative stress level and some antioxidant activities in refractory epilepsy patients

The aim of this study was to determine the levels of superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and malondialdehyde (MDA) in patients with refractory epilepsy. Serum superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and malondialdehyde (MDA) levels were determined using the spectrophotometer method. Refractory epilepsy patients' serum superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and malondialdehyde (MDA) levels were statistically significant compared to the healthy control group (p < 0.05). In conclusion, superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and malondialdehyde (MDA) levels may play an important role in the etiopathogenesis of refractory epilepsy. This study was the first to investigate some parameters in refractory epilepsy disease.

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.

Role of Neurogenesis and Oxidative Stress in Epilepsy (Study on Plasma Brain Derived Neurotrophic Factor and Malondialdehyde Level)

BACKGROUND: Epilepsy is a neurological disorder. Its incidence in Indonesia was 700,000–1,400,000 cases and 40–50% occurred in children. About 30–40% of cases in children had uncontrolled seizures. Biomarkers are needed to assess the prognostic value of patients with uncontrolled epilepsy. Malondialdehyde (MDA) and brain-derived neurotrophic factor (BDNF) are one of the prognostic biomarkers related to uncontrolled epilepsy to see the effect of oxidative stress and neuroplasticity. AIM: The objective of the study was to examine cut off value of plasma BDNF and MDA level; and to compare plasma BDNF and MDA levels in uncontrolled and controlled epilepsy patients. METHODS: The research usedanalytic observational with cross-sectional approach. Number of respondents was 30 patients of epilepsy who came to Ulin Hospital Banjarmasin. Respondents were divided into two groups (controlled and uncontrolled epilepsy). Blood plasma was examined for MDA with a spectrophotometer and BDNF with ELISA. Data were analyzed by t-test with 95% confidence level. RESULTS: 11 children were found in the uncontrolled epilepsy group and 19 children with controlled epilepsy. The result showed that there were significant differences between type of therapy and developmental disorders/other diseases with epilepsy status. There was no significant differences of plasma BDNF in epilepsy status (controlled and uncontrolled epilepsy), and there was also no significant differences of plasma MDA in epilepsy status (controlled and uncontrolled epilepsy). CONCLUSION: There were no significant differences of plasma BDNF and MDA in epilepsy status.

4-Phenylbutyric Acid Plus Valproic Acid Exhibits the Therapeutic and Neuroprotective Effects in Acute Seizures Induced by Pentylenetetrazole

Endoplasmic reticulum (ER) stress and apoptosis are implicated in the pathogenesis of epilepsy. Here we examine the effects of valproic acid (VA) plus 4-phenylbutyric acid (4-PBA) on abnormal electrical brain activity, ER stress and apoptosis in acute seizures induced by pentylenetetrazole (PTZ). Forty male rats were randomly divided into five groups, each consisting of 8 rats as follows: Sham, PTZ, VA+PTZ, 4-PBA+PTZ, and VA plus 4-PBA+PTZ. The treated groups received VA, 4-PBA and VA plus 4-PBA by intraperitoneal application for 7 days prior to PTZ-induced seizure. On the 8th day, acute epileptic seizures were induced by PTZ (50 mg/kg, i.p.) injection, except for the sham group. Then, the seizure stage was observed and ECoG activities were recorded during the 30 min. At 24th post seizures, the hippocampus and blood samples were collected for biochemical and histopathological examinations. Administration of VA plus 4-PBA prior to PTZ-induced seizures significantly decreased seizure stage, the duration of generalized tonic-clonic seizure and the total number of spikes as increased the latency to the first myoclonic jerk when compared to the PTZ group. 4-PBA suppressed the increased levels of ER stress markers GRP78 and CHOP in the hippocampus. VA plus 4-PBA treatment before seizures significantly inhibited PTZ-induced elevations of apoptosis-related indicators caspase-3 and caspase-12, and significantly reduced the number of histopathological lesions of the hippocampus region at 24th post seizures. These findings suggest that administration of VA plus 4-PBA prior to PTZ-induced seizures may be involved in the neuroprotective potential of these agents for seizures.

Malondialdehyde and superoxide dismutase levels in patients with epilepsy: a case–control study

Background

Oxidative stress has a significant influence in the initiation and progression of epileptic seizures. It was reported that inhibiting oxidative stress could protect against epilepsy. The aim of the current research is to estimate some biomarkers that reflect the oxidative stress in epileptics, its relation to seizure control as well as to study the impact of antiepileptic drugs (AEDs) on these biomarkers. This case–control study included 62 epileptic patients beside 62 age and gender-matched healthy controls. The epileptic patients subjected to detailed history taking with special regards to disease duration, seizure frequency, and the current AEDs. Laboratory evaluation of serum malondialdehyde (a lipid peroxidation byproduct) and superoxide dismutase (an endogenous antioxidant) were done.

Results

Malondialdehyde (MDA) was significantly higher, and superoxide dismutase (SOD) was lower in epileptic patients than in the controls (p < 0.001). Seizure frequency was directly correlated with MDA (r = 0.584, p < 0.001) while inversely correlated with SOD (r = − 0.432, p = 0.008). High MDA and low SOD were recorded in epileptic patients receiving polytherapy as compared to monotherapy (p < 0.001).

Conclusions

Epileptic patients had higher oxidative stress biomarkers than healthy individuals. Frequent seizures, long disease duration, and AEDs were associated with higher MDA and lower SOD that reflects an imbalance in the oxidant–antioxidant status among these patients.

A Novel Pathway Phenotype of Temporal Lobe Epilepsy and Comorbid Psychiatric Disorders: Results of Precision Nomothetic Medicine

No precision medicine models of temporal lobe epilepsy (TLE) and associated mental comorbidities have been developed to date. This observational study aimed to develop a precision nomothetic, data-driven comorbid TLE model with endophenotype classes and pathway phenotypes that may have prognostic and therapeutical implications. We recruited forty healthy controls and 108 TLE patients for this research and assessed TLE and psychopathology (PP) features as well as oxidative stress (OSTOX, e.g., malondialdehyde or MDA, lipid hydroperoxides, and advanced oxidation protein products) and antioxidant (paraoxonase 1 or PON1 status, -SH groups, and total radical trapping potential or TRAP) biomarkers. A large part (57.2%) of the variance in a latent vector (LV) extracted from the above TLE and PP features was explained by these OSTOX and antioxidant biomarkers. The PON1 Q192R genetic variant showed indirect effects on this LV, which were completely mediated by PON1 activity and MDA. Factor analysis showed that a common core could be extracted from TLE, PP, OSTOX and antioxidant scores, indicating that these features are manifestations of a common underlying construct, i.e., a novel pathway phenotype of TLE. Based on the latter, we constructed a new phenotype class that is characterized by increased severity of TLE, PP and OSTOX features and lowered antioxidant defenses. A large part of the variance in episode frequency was explained by increased MDA, lowered antioxidant, and nitric oxide metabolite levels. In conclusion, (a) PP symptoms belong to the TLE phenome, and the signal increased severity; and (b) cumulative effects of aldehyde formation and lowered antioxidants determine epileptogenic kindling.

Reduced paraoxonase 1 activities may explain the comorbidities between temporal lobe epilepsy and depression, anxiety and psychosis

BACKGROUND

Temporal lobe epilepsy (TLE) is the most common focal epilepsy subtype in adults and is frequently accompanied by depression, anxiety and psychosis. Aberrations in total paraoxonase 1 (PON1) status may occur in TLE and these psychiatric conditions.

AIM

To examine PON1 status, namely Q192R PON1 genotypes and PON1 enzymatic activities, in TLE.

METHODS

We recruited 40 normal controls and 104 TLE patients, 27 without comorbidities and 77 with comorbidities including mood disorders (n = 25), anxiety disorders (n = 27) and psychosis (n = 25).

RESULTS

Four-(chloromethyl)phenyl acetate hydrolysis (CMPAase) and arylesterase activities were significantly lower in TLE and mesial temporal sclerosis (MTS) with and without psychiatric comorbidities than those in normal controls. The areas under the receiver operating characteristic curve of CMPAase were 0.893 (0.037) for TLE and 0.895 (± 0.037) for MTS. Partial least squares path analysis showed that there were specific indirect effects of PON1 genotype on TLE severity (P < 0.0001) and psychopathology (P < 0.0001), which were both mediated by lowered CMPAase activity, while arylesterase activity was not significant. The severity of TLE was significantly associated with psychopathology scores. Furthermore, PON1 CMPAase activity was inversely associated with Mini Mental State Examination score.

CONCLUSION

The severity of TLE and comorbidities are to a large extent explained by reduced PON1 enzyme activities and by effects of the Q192R genotype, which are mediated by reduced CMPAase activity. Total PON1 status plays a key role in the pathophysiology of TLE, MTS and psychiatric comorbidities by increasing the risk of oxidative toxicity. PON1 enzyme activities are new drug targets in TLE to treat seizure frequency and psychiatric comorbidities.

Evaluation of serum thiol-disulphide homeostasis parameters as oxidative stress markers in epilepsy patients

The present study focuses on the investigation of the dynamic thiol-disulphide homeostasis in patients with epilepsy and understanding the effects of antiepileptic drugs on thiol levels. A total of 148 participants, 75 of whom had epilepsy and 73 were healthy volunteers, were included in the study. Total thiol and native thiol levels of all epilepsy patients and healthy volunteers were measured. Disulphide level, disulphide/native thiol, disulphide/total thiol and native/total thiol ratios were calculated from these values. The results were compared between epilepsy patients and healthy volunteers. A statistically significant difference was found between native thiol level, total thiol level, disulphide level, disulfide/total thiol, disulphide/native thiol and native/total thiol ratios between patients with epilepsy and healthy volunteers (p = 0.002, p = 0.035, p < 0.001, p < 0.001, p < 0.001, p < 0.001, respectively). The drugs used had a significant effect on disulphide, disulphide/total thiol, native/total thiol levels (p values 0.004, 0.009, 0.009, respectively). Decreased levels of serum native, total thiol and increased disulfide levels as parameters of oxidative stress may be considered as parameters to explain the pathogenesis or consequences of epilepsy.

Atherogenic Risk Factors among Young Indian Adults with Epilepsy on Treatment with Phenytoin: Need for Novel Therapeutic Strategies

Background

Risk for the development of coronary heart disease and diabetes is found to be more among people with epilepsy especially when on treatment. Redox imbalance contributes to this risk especially in India as it is the diabetic capital of the world with higher prevalence of inflammation.

Objectives

The aim of this study was to evaluate atherogenic risk factors; dyslipidemia, oxidative stress, and systemic inflammation among young Indian adults with epilepsy on treatment with Phenytoin.

Material and Methods

Three groups of age and gender-matched young subjects were recruited. Group 1-Healthy control subjects, Group 2- Newly diagnosed epileptic young adults with recent epileptic seizures, Group 3- Epileptic adults on treatment with Phenytoin for more than 6 months were recruited.

Results

Dyslipidemia was found among the newly diagnosed epileptic subjects in comparison to healthy subjects. The LDL-cholesterol further increased, and HDL-cholesterol further decreased in the third group treated with Phenytoin. Body mass index of these treated epileptic subjects was more in comparison to healthy control. Low-grade inflammation as assessed by hsCRP and oxidative stress were significantly higher among the newly diagnosed epileptic subjects when compared to the healthy controls which further increased on treatment with phenytoin. We found dyslipidemia, oxidative stress, and low-grade inflammation among newly diagnosed epileptic subjects which further increased on treatment with Phenytoin for more than 6 months.

Conclusion

From this study, we conclude that dyslipidemia, oxidative stress and low-grade inflammation are identified among the newly diagnosed young adult Indian epileptic patients. Phenytoin treatment further augmented these complications.

Interweaving epilepsy and neurodegeneration: Vitamin E as a treatment approach

Epilepsy is the most common neurological disorder, affecting nearly 50 million people worldwide. The condition can be manifested either due to genetic predisposition or acquired from acute insult which leads to alteration of cellular and molecular mechanisms. Evaluating the latest and the current knowledge in regard to the mechanisms underlying molecular and cellular alteration, hyperexcitability is a consequence of an imbalanced state wherein enhance excitatory glutamatergic and reduced inhibitory GABAergic signaling is considered to be accountable for seizures associated damage. However, neurodegeneration contributing to epileptogenesis has become increasingly appreciated. The components at the helm of neurodegenerative alterations during epileptogenesis include GABAergic neuronal and receptor changes, neuroinflammation, alteration in axonal transport, oxidative stress, excitotoxicity, and other cellular as well as functional changes. Targeting neurodegeneration with vitamin E as an antioxidant, anti-inflammatory and neuroprotective may prove to be one of the therapeutic approaches useful in managing epilepsy. In this review, we discuss and converse about the seizure-induced episodes as a link for the development of neurodegenerative and pathological consequences of epilepsy. We also put forth a summary of the potential intervention with vitamin E therapy in the management of epilepsy.

Is oxidative stress an overlooked player in pyridoxine-dependent epilepsy? A focused review

Pyridoxine-dependent epilepsy (PDE) is a rare autosomal recessive developmental and epileptic encephalopathy that is responsive to pharmacologic doses of vitamin B₆. The deficiency of antiquitin, an enzyme involved in the catabolism of lysine, is believed to be its key molecular basis. Research to date has tended to focus on two known catabolic pathways of lysine, namely, saccharopine and pipecolic acid. However, the occurrence of oxidative stress and the presence of its metabolites have been only briefly highlighted in the literature. Owing to the importance of the topic and its potential for future diagnosis, prognosis and therapy, this paper reviews the suggested mechanisms of oxidative stress in antiquitin deficiency along with the proposed reactions and intermediates, and finally, discusses the challenges and opportunities.

Effects of the Calcium Channel Blocker Otilonium Bromide on Seizure Activity in Rats With Pentylenetetrazole-Induced Convulsions

Millions of people suffer from drug-resistant epilepsy. New therapeutic approaches for removing this life-affecting disease are required. The activation of T-type calcium channels (TTCC) is one of the epileptogenesis mechanisms that cause epilepsy. So, we researched the effects of Otilonium bromide (OB), an antisposmolytic drug that inhibits TTCC, on seizure activity in rats with pentylenetetrazol (PTZ) induced convulsion. Randomly, 48 rats were divided into two groups; for electroencephalography (EEG) recordings and for behavioral assesment. Rats were treated with either intraperitoneal (IP) OB at two separate doses (25 mg/kg and 50 mg/kg) or placebo, and then pentylenetetrazole (IP), a potent seizure-inducing chemical administered to them. In our model we have measured rat seizure activity with EEG, the convulsion scala of Racine (RCS), the time of first myoclonic jerk (FMJ) and MDA levels to assess if OB has antiepileptic properties. The mean EEG spike wave percentage score reduced from 79.5% (placebo) to 59.2% (lower-dose) and 35.2% (higher-dose). FMJ had increased from a mean of 67.2 s (placebo), to 105.2 (lower-dose), 150.6 (higher-dose). RCS reduced from a mean of 5.12 (placebo) to 4.4 (lower-dose), 3.8 (higher-dose). MDA leves reduced from 84.5 nmol/gr to 51.09 nmol/gr (lower-dose), 33.2 nmol/gr (higher-dose). Compared to placebo, OB reduced significantly seizure activity at both doses, probably through blocking T-type calcium channels. All these results were statistically significant with < 0.0001 p-values. Otilonium bromide reduced seizure activity in rats with PTZ-induced convulsion. Therefore, the clinical role of OB and other TTCC inhibitors as potential anti-seizure drugs should be further investigated.

Evaluation of IL-10, IFN-γ, and thiol-disulfide homeostasis in patients with drug-resistant epilepsy

AIM

This study compared dynamic thiol-disulfide homeostasis (an oxidative stress marker), anti-inflammatory interleukin-10 (IL-10) levels, and proinflammatory interferon gamma (IFN-γ) levels in drug-resistant epilepsy patients with those in patients with well-controlled epilepsy and healthy controls.

METHOD

This prospective cross-sectional study enrolled 89 people: 27 with drug-resistant epilepsy, 30 with well-controlled epilepsy, and 32 healthy controls matched in demographic characteristics.

RESULTS

The mean serum IL-10 levels were significantly lower and the mean serum IFN-γ levels significantly higher in the drug-resistant epilepsy patients compared to the well-controlled epilepsy and healthy control groups. The mean serum native thiol (SH) and total thiol (TT) levels were significantly lower, and the disulfide (SS) levels were significantly higher in the drug-resistant group than in the other two groups.

CONCLUSIONS

The significant differences in thiol-disulfide homeostasis and IL-10 and IFN-γ levels in the drug-resistant epilepsy group suggest that these markers indicate a poor prognosis in epilepsy.

Melatonin as an Antiepileptic Molecule: Therapeutic Implications via Neuroprotective and Inflammatory Mechanisms

Epilepsy is a result of unprovoked, uncontrollable, and repetitive outburst of abnormal and excessive electrical discharges, known as seizures, in the neurons. Epilepsy is a devastating neurological condition that affects 70 million people globally. Unfortunately, only two-thirds of epilepsy patients respond to antiepileptic drugs while others become drug resistant and may be more prone to epilepsy comorbidities such as SUDEP. Oxidative stress, mitochondrial dysfunction, imbalance in the excitatory and inhibitory neurotransmitters, and neuroinflammation are some of the common pathologies of neurological disorders and epilepsy. Studies suggests that melatonin, a pineal hormone that governs sleep-wake cycles, may be neuroprotective against neurological disorders and thus may be translated as an antiepileptic as well. Melatonin has been shown to be an antioxidant, antiexcitotoxic, and anti-inflammatory hormone/molecule in neurodegenerative diseases, which may contribute to its antiepileptic and neuroprotective properties in epilepsy as well. In addition, melatonin has evidently been shown to play a regulatory role in the cardiorespiratory system and sleep-wake cycles, which may have positive implications toward epilepsy associated comorbidities, such as SUDEP. However, studies investigating the changes in melatonin release due to epilepsy and melatonin's antiepileptic role have been inconclusive and scarce, respectively. Thus, this comprehensive review aims to summarize and elucidate the potential role of melatonin in the pathogenesis of epilepsy and its comorbidities, in hopes to develop new diagnostic and therapeutic approaches that will improve the lives of epileptic patients, particularly those who are drug resistant.

Neuroprotective Effect of Protaetia brevitarsis seulensis' Water Extract on Trimethyltin-Induced Seizures and Hippocampal Neurodegeneration

This study aimed to investigate whether the Protaetia brevitarsis seulensis (PB)’ water extract (PBWE) ameliorates trimethyltin (TMT)-induced seizures and hippocampal neurodegeneration. To investigate the potential neuroprotective effect of the PBWE in vitro, a lactate dehydrogenase (LDH) assay was conducted in TMT-treated primary cultures of mouse hippocampal neurons. In TMT-treated adult C57BL/6 mice, behavioral and histopathological changes were evaluated by seizure scoring and Fluoro-Jade C staining, respectively. In our in vitro assay, we observed that pretreating mice hippocampal neuron cultures with the PBWE reduced TMT-induced cytotoxicity, as indicated by the decreased LDH release. Furthermore, pretreatment with the PBWE alleviated seizures and hippocampal neurodegeneration in TMT-treated mice. The antioxidant activity of the PBWE increased in a dose-dependent manner; moreover, pretreatment with the PBWE mitigated the TMT-induced Nrf2 stimulation. In addition, six major compounds, including adenine, hypoxanthine, uridine, adenosine, inosine, and benzoic acid, were isolated from the PBWE, and among them, inosine and benzoic acid have been confirmed to have an essential antioxidative activity. In conclusion, the PBWE ameliorated TMT-induced toxicity in hippocampal neurons in both in vitro and in vivo assays, through a potential antioxidative effect. Our findings suggest that the PBWE may have pharmacotherapeutic potential in neurodegenerative diseases such as seizures or epilepsy.

Approaches for Reactive Oxygen Species and Oxidative Stress Quantification in Epilepsy

Oxidative stress (OS) and excessive reactive oxygen species (ROS) production have been implicated in many neurological pathologies, including acute seizures and epilepsy. Seizure-induced damage has been demonstrated both in vitro and in several in vivo seizure and epilepsy models by direct determination of ROS, and by measuring indirect markers of OS. In this manuscript, we review the current reliable methods for quantifying ROS-related and OS-related markers in pre-clinical and clinical epilepsy studies. We first provide pieces of evidence for the involvement of different sources of ROS in epilepsy. We then discuss general methods and assays used for the ROS measurements, mainly superoxide anion, hydrogen peroxide, peroxynitrite, and hydroxyl radical in in vitro and in vivo studies. In addition, we discuss the role of these ROS and markers of oxidative injury in acute seizures and epilepsy pre-clinical studies. The indirect detection of secondary products of ROS such as measurements of DNA damage, lipid peroxidation, and protein oxidation will also be discussed. This review also discusses reliable methods for the assessment of ROS, OS markers, and their by-products in epilepsy clinical studies.

Increased Oxidative Stress Toxicity and Lowered Antioxidant Defenses in Temporal Lobe Epilepsy and Mesial Temporal Sclerosis: Associations with Psychiatric Comorbidities

Oxidative stress toxicity (OSTOX), as well as lowered antioxidant defenses (ANTIOX), plays a role in temporal lobe epilepsy (TLE). Nevertheless, the associations between OSTOX/ANTIOX and psychiatric comorbidities in TLE are largely unknown. Thus, this study examines plasma malondialdehyde (MDA), lipid hydroperoxides (LOOH), advanced oxidation protein products (AOPP), nitric oxide metabolites (NO_x), total radical-trapping antioxidant parameter (TRAP), and sulfhydryl (-SH) groups in depression due to TLE (n = 25); anxiety disorders due to TLE (n = 27); psychotic disorder due to TLE (n = 25); "pure TLE" (n = 27); and healthy controls (n = 40). TLE and mesial temporal sclerosis (MTS) were characterized by significant increases in OSTOX (MDA, AOPP, LOOH) and lowered ANTIOX (-SH groups, TRAP). The discrimination of pure TLE from controls yielded a significant area under the ROC curve for MDA (0.999), AOPP (0.851), -SH groups (0.899), and the OSTOX/ANTIOX ratio (0.996). Seizure frequency is significantly associated with increased MDA and lowered LOOH and NO_x levels. Increased MDA was associated with the severity of depressive and physiosomatic symptoms, while increased AOPP levels predicted suicidal ideation. Depression and anxiety disorders co-occurring with TLE showed significantly lower MDA levels than TLE without any comorbidities. The psychotic and negative symptoms of TLE are associated with increased MDA levels and excitation with increased LOOH and lowered TRAP levels. These results indicate that oxidative stress toxicity especially protein oxidation and aldehyde formation coupled with lowered -SH groups plays a key role in the pathophysiology of TLE/MTS. Increased aldehyde formation also impacts psychopathology and psychosis, as well as negative and depressive symptoms.

Effect of levetiracetam drug on antioxidant and liver enzymes in epileptic patients: case-control study

BACKGROUND

There is a limited amount of data regarding levetiracetam (LEV), an antiepileptic drug.

OBJECTIVE

This study was conducted to assess the effect of LEV on antioxidant status and liver enzymes.

METHODS

In this case-control study, 33 epileptic patients under treatment with LEV for at least 6 months were compared with 35 healthy subjects. We measured serum total antioxidant capacity (TAC), salivary superoxide dismutase (SOD), alanine aminoteransferase (ALT), and aspartate aminoteransferase (AST) levels in both groups. Dietary intakes were collected using a Food Frequency Questionnaire (FFQ).

RESULT

The level of TAC in the healthy subjects was significantly higher than it was in the patients (P=0.02), but the mean of ALT (P=0.02) and AST (P=0.03) was significantly higher in the patients in comparison with the controls. Mean salivary SOD showed no difference between the two groups. In the patients, the duration of drug use was inversely correlated with serum TAC (p=0.04) and had a direct correlation with ALT (p=0.01) and AST (p=0.03.).

CONCLUSION

The results of our study indicated that LEV increased liver enzymes Also, treatment with this drug did not improve oxidative stress, but this could be due to the different in the dietary antioxidant intake. Routine screening of the liver and antioxidant enzymes in patients with chronic use of LEV is recommended.

Determination of levels of oxidative stress and nitrosative stress in patients with epilepsy

BACKGROUND

Epilepsy is one of the most common neurological diseases. The underlying pathophysiological mechanisms in epilepsy are still unknown. Oxidative stress is believed to be one of the factors involved in the pathogenesis of epileptogenesis. In various pathophysiological conditions, reactive nitrogen species (RNS) such as nitrogen and peroxynitrite are produced and these RNSs can bind to free nucleosides and nucleotides or to nucleosides and nucleotides existing in the DNA/RNA structure. 8-Nitroguanine (8-NG) is a typical DNA nucleobase product of nitrosative damage generated by RNS. It has been proposed that F2-isoprostanes, in particular 8-iso-Prostaglandin F2α (8-isoPGF2α), are specific, reliable and non-invasive biomarkers of lipid peroxidation in vivo. In the present study, we compared the levels of lipid oxidative stress biomarker 8-isoPGF2α and nitrosative stress DNA biomarker 8-NG in patients with epilepsy undergoing antiepileptic drug (AEDs) treatment and with those in healthy participants.

METHODS

The present study comprised 90 patients aged between 17 and 53 who were admitted to the Neurology Clinic of Cumhuriyet University and diagnosed with epilepsy. The patients were assigned into the intervention (n = 45) and control (n = 45) groups. Of the participants in the intervention group, 37.7% (n = 17) were treated with levetiracetam (LEV), 33.3% (n = 15) with valproic acid (VA) and 29% (n = 13) with carbamazepine. Serum 8-iso-PGF2α and 8-NG levels of the participants in the intervention and control groups were determined by ELISA.

RESULTS

There was no significant difference between the medication (LEV, VA, Carbamazepine) used by the participants and their 8-iso-PGF2α and 8-NG levels (p > 0.05). However, 8-iso-PGF2α and 8-NG were significantly higher in the participants in the intervention than in the participants in the control group (p < 0.001).

CONCLUSION

Our study demonstrated that there was an increase in oxidative and nitrosative stres markers in patients with epilepsy. There was no significant difference between the 8-iso-PGF2α and 8-NG levels of the participants taking three different AEDs.

Apoptotic Markers Are Increased in Epilepsy Patients: A Relation with Manganese Superoxide Dismutase Ala16Val Polymorphism and Seizure Type through IL-1β and IL-6 Pathways

The MnSOD Ala16Val single nucleotide polymorphism (SNP) has been associated with different diseases. However, there are scarcely studies relating this SNP in epilepsy, a neurologic disease that involves some interacting pathways, such as apoptotic and inflammatory factors. In this sense, we decided to investigate the relationship of MnSOD Ala16Val SNP with apoptotic markers in epilepsy and its relation with inflammatory pathway and seizure type. Ninety subjects were evaluated (47 epilepsies; 43 controls) by questionnaires and laboratorial exams. We observed a higher percentage of VV genotype in the epilepsy group when compared to the control group. IL-1β, IL-6, caspase-1, and caspase-3 levels were increased in the epilepsy group (VV genotype). Furthermore, an important correlation between IL-1β vs. caspase-1 and IL-6 vs. caspase-3 was observed in the epilepsy group (VV genotype). The epilepsy group which presented generalized seizures also demonstrated a positive correlation between IL-1β vs. CASP1 and IL-6 vs. CASP3. Thus, it is a plausible propose that epilepsy patients with VV genotype and generalized seizures present a worse inflammatory and apoptotic status. Our findings suggest that the knowledge of MnSOD Ala16Val polymorphism existence is important to evaluate molecular mechanisms associated to seizure and improve the treatment of these patients.

Inflammation and reactive oxygen species in status epilepticus: Biomarkers and implications for therapy

Preclinical studies in immature and adult rodents and clinical observations show that neuroinflammation and oxidative stress are rapid onset phenomena occurring in the brain during status epilepticus and persisting thereafter. Notably, both neuroinflammation and oxidative stress contribute to the acute and long-term sequelae of status epilepticus thus representing potential druggable targets. Antiinflammatory drugs that interfere with the IL-1β pathway, such as anakinra, can control benzodiazepine-refractory status epilepticus in animals, and there is recent proof-of-concept evidence for therapeutic effects in children with Febrile infection related epilepsy syndrome (FIRES). Inhibitors of monoacylglycerol lipase and P2X7 receptor antagonists are also promising antiinflammatory drug candidates for rapidly aborting de novo status epilepticus and provide neuroprotection. Antiinflammatory and antioxidant drugs administered to rodents during status epilepticus and transiently thereafter, prevent long-term sequelae such as cognitive deficits and seizure progression in animals developing epilepsy. Some drugs are already in medical use and are well-tolerated, therefore, they may be considered for treating status epilepticus and its neurological consequences. Finally, markers of neuroinflammation and oxidative stress are measureable in peripheral blood and by neuroimaging, which offers an opportunity for developing prognostic and predictive mechanistic biomarkers in people exposed to status epilepticus. This article is part of the Special Issue "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures.

NMR-based metabolomics in pediatric drug resistant epilepsy - preliminary results

Epilepsy in children is the most frequent, heterogeneous and difficult to classify chronic neurologic condition with the etiology found in 35–40% of patients. Our aim is to detect the metabolic differences between the epileptic children and the children with no neurological abnormalities in order to define the metabolic background for therapy monitoring. The studied group included 28 epilepsy patients (median age 12 months) examined with a diagnostic protocol including EEG, videoEEG, 24-hour-EEG, tests for inborn errors of metabolism, chromosomal analysis and molecular study. The reference group consisted of 20 patients (median age 20 months) with no neurological symptoms, no development delay nor chronic diseases. ¹H-NMR serum spectra were acquired on 400 MHz spectrometer and analyzed using multivariate and univariate approach with the application of correction for age variation. The epilepsy group was characterized by increased levels of serum N-acetyl-glycoproteins, lactate, creatine, glycine and lipids, whereas the levels of citrate were decreased as compared to the reference group. Choline, lactate, formate and dimethylsulfone were significantly correlated with age. NMR-based metabolomics could provide information on the dynamic metabolic processes in drug-resistant epilepsy yielding not only disease-specific biomarkers but also profound insights into the disease course, treatment effects or drug toxicity.

Effect of probiotic supplementation on seizure activity and cognitive performance in PTZ-induced chemical kindling

Epilepsy is one of the most common neurological disorders that severely affect life quality of many people worldwide. Ion transport in the neuronal membrane, inhibitory-excitatory mechanisms, and regulatory modulator systems have been implicated in the pathogenesis of epilepsy. A bidirectional communication is proposed between brain and gut where the brain modulates the gastrointestinal tract, and the gut can affect brain function and behavior. The gut microbiome takes an important role in health and disease where dysbiosis is involved in several neurological disorders. Probiotics as living microorganisms are beneficial to humans and animals when adequately administered. In the present work, we evaluated the effect of a probiotic bacteria mixture on seizure activity, cognitive function, and gamma-aminobutyric acid (GABA), nitric oxide (NO), malondealdehyde (MDA), and total antioxidant capacity (TAC) level of the brain tissue in the pentylenetetrazole (PTZ)-induced kindled rats. The Racine score and performance in water maze were considered as indices of the epileptic severity and the spatial learning and memory, respectively. We found that the probiotic supplementation substantially reduces seizure severity so that almost no probiotic-treated animals showed full kindling. The oral bacteriotherapy partially improved the spatial learning and memory in the kindled rats. The intervention decreased NO and MDA and increased TAC concentration of the brain. The probiotic treatment also increased the inhibitory neurotransmitter GABA. Our findings are the first preclinical report to show positive effect of probiotic bacteria on seizure-induced neurological disorders. Further investigation is required to answer the questions raised about the probable mechanisms involved.

The Neuroprotective Effect of Astaxanthin on Pilocarpine-Induced Status Epilepticus in Rats

Cognitive dysfunction is one of the serious complications induced by status epilepticus (SE), which has a significant negative impact on patients’ quality of life. Previous studies demonstrated that the pathophysiological changes after SE such as oxidative stress, inflammatory reaction contribute to neuronal damage. A recent study indicated that preventive astaxanthin (AST) alleviated epilepsy-induced oxidative stress and neuronal apoptosis in the brain. In the present study, rats were treated with vehicle or AST 1 h after SE onset and were injected once every other day for 2 weeks (total of seven times). The results showed that the cognitive function in SE rats was significantly impaired, and AST treatment improved cognitive function in the Morris water maze (MWM). Magnetic resonance imaging (MRI), hematoxylin-eosin (HE) staining and TdT-mediated dUTP Nick-End Labeling (TUNEL) staining showed obvious damage in the hippocampus of SE rats, and AST alleviated the damage. Subsequently, we evaluated the effect of AST on relative pathophysiology to elucidate the possible mechanisms. To evaluate the oxidative stress, the expression of malondialdehyde (MDA) and superoxide dismutase (SOD) in plasma were detected using commercially available kits. NADPH oxidase-4 (Nox-4), p22phox, NF-E2-related factor 2 (Nrf-2), heme oxygenase 1 (Ho-1) and sod1 in the parahippocampal cortex and hippocampus were detected using western blot and real-time polymerase chain reaction (RT-PCR). The levels of MDA in plasma and Nox-4 and p22phox in the brain increased in SE rats, and the levels of SOD in plasma and Nrf-2, Ho-1 and sod1 in the brain decreased. Treatment with AST alleviated these changes. We also detected the levels of inflammatory mediators like cyclooxygenase-2 (cox-2), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and NF-κB phosphorylation p65 (p-p65)/p65 in the brain. The inflammatory reaction was significantly activated in the brain of SE rats, and AST alleviated neuroinflammation. We detected the levels of p-Akt, Akt, B-cell lymphoma-2 (Bcl-2), Bax, cleaved caspase-3, and caspase-3 in the parahippocampal cortex and hippocampus using western blot. The levels of p-Akt/Akt and Bcl-2 decreased in SE rats, Bax and cleaved caspase-3/caspase-3 increased, while AST alleviated these changes. The present study indicated that AST exerted an reobvious neuroprotective effect in pilocarpine-induced SE rats.

Targeting ferroptosis: A novel therapeutic strategy for the treatment of mitochondrial disease-related epilepsy

BACKGROUND

Mitochondrial disease is a family of genetic disorders characterized by defects in the generation and regulation of energy. Epilepsy is a common symptom of mitochondrial disease, and in the vast majority of cases, refractory to commonly used antiepileptic drugs. Ferroptosis is a recently-described form of iron- and lipid-dependent regulated cell death associated with glutathione depletion and production of lipid peroxides by lipoxygenase enzymes. Activation of the ferroptosis pathway has been implicated in a growing number of disorders, including epilepsy. Given that ferroptosis is regulated by balancing the activities of glutathione peroxidase-4 (GPX4) and 15-lipoxygenase (15-LO), targeting these enzymes may provide a rational therapeutic strategy to modulate seizure. The clinical-stage therapeutic vatiquinone (EPI-743, α-tocotrienol quinone) was reported to reduce seizure frequency and associated morbidity in children with the mitochondrial disorder pontocerebellar hypoplasia type 6. We sought to elucidate the molecular mechanism of EPI-743 and explore the potential of targeting 15-LO to treat additional mitochondrial disease-associated epilepsies.

METHODS

Primary fibroblasts and B-lymphocytes derived from patients with mitochondrial disease-associated epilepsy were cultured under standardized conditions. Ferroptosis was induced by treatment with the irreversible GPX4 inhibitor RSL3 or a combination of pharmacological glutathione depletion and excess iron. EPI-743 was co-administered and endpoints, including cell viability and 15-LO-dependent lipid oxidation, were measured.

RESULTS

EPI-743 potently prevented ferroptosis in patient cells representing five distinct pediatric disease syndromes with associated epilepsy. Cytoprotection was preceded by a dose-dependent decrease in general lipid oxidation and the specific 15-LO product 15-hydroxyeicosatetraenoic acid (15-HETE).

CONCLUSIONS

These findings support the continued clinical evaluation of EPI-743 as a therapeutic agent for PCH6 and other mitochondrial diseases with associated epilepsy.

Immunohistochemical Study of Antioxidant Enzymes Regulated by Nrf2 in the Models of Epileptic Seizures (KA and PTZ)

Epilepsy is a neurological disorder characterized by recurrent spontaneous seizures due to an imbalance between cerebral excitability and inhibition, with a tendency towards uncontrolled excitability. Epilepsy has been associated with oxidative and nitrosative stress due to prolonged neuronal hyperexcitation and loss neurons during seizures. The experimental animal models report level of ATP diminished and increase in lipid peroxidation, catalase, and glutathione altered activity in the brain. We studied the immunohistochemical expression and localization of antioxidant enzymes GPx, SOD, and CAT in the rat brains treated with KA and PTZ. A significant decrease was observed in the number of immunoreactive cells to GPx, without significant changes for SOD and CAT in KA-treated rats, and decrease in the number of immunoreactive cells to SOD, without significant changes for GPx and only CAT in PTZ-treated rats. Evident immunoreactivity of GPx, SOD, and CAT was observed mainly in astrocytes and neurons of the hippocampal brain region in rats exposed at KA; similar results were observed in rats treated with PTZ at the first hours. These results provide evidence supporting the role of activation of the Nrf2 antioxidant system pathway against oxidative stress effects in the experimental models of epileptic seizures.

Effects of levetiracetam and valproic acid treatment on liver function tests, plasma free carnitine and lipid peroxidation in childhood epilepsies

BACKGROUND AND AIMS

The relationship between anti-epileptic usage and oxidative damage has not yet been clearly understood. In our study, we investigated oxidative stress parameters, carnitine levels, liver function tests (LFT) and their relationship in epileptic children treated with valproic acid or levetiracetam.

METHOD

LFTs, serum free carnitine and oxidative damage markers and their relations with each other were determined in patients who are on valproic acid or levetiracetam treatment at least for 6 months. 25 patients on therapeutic doses of valproic acid, 26 patients on therapeutic doses of levetiracetam and 26 healthy volunteers as controls were included. LFTs, ammonia, carnitine, lipid peroxidation biomarker malondialdehyde (MDA) and a sensitive marker of DNA damage, 8-hydroxy-2-deoxyguanosine (8-OHdG) levels were measured. Results of patients are compared to healthy controls. The data is evaluated with IBM SPSS Statistics 22.0.

RESULTS

Ammonia and MDA levels were elevated in patients using levetiracetam; 8-OHdG levels were elevated in both patient groups. Carnitine levels were significantly low in patients under valproic acid therapy, however they were not found to be correlated with MDA, 8-OHdG or LFTs. MDA showed positive correlation with ammonia and 8-OHdG in the levetiracetam group.

CONCLUSION

We did not observe hepatotoxicity in patients under therapeutic doses of valproic acid. However, epileptic children under therapeutic doses of levetiracetam showed significantly elevated levels of MDA and 8-OHdG, which is supportive for oxidative damage under levetiracetam therapy. This result was observed for the first time in childhood epilepsies and further studies are needed to understand its mechanism.

Oxidative stress contribution to attention deficit hyperactivity disorder in children with epilepsy

Children with epilepsy have a high incidence of attention deficit hyperactivity disorder (ADHD). Oxidation stress and disturbed neurotransmitters are suggested mechanisms; however, their role is not fully explored. This study evaluates the association between circulating malondialdehyde as an oxidation stress marker, apelin neuropeptide, and ADHD in children with epilepsy. Fifty children with epilepsy of unknown etiology, of which 25 have ADHD, as well as 35 healthy children were included. Serum levels of malondialdehyde and apelin were estimated. We investigated the association between seizure severity, response to medications, malondialdehyde, apelin levels, and ADHD in children with epilepsy. Serum malondialdehyde and apelin levels were higher in children with epilepsy, especially those with ADHD. Malondialdehyde and apelin levels have significant positive correlation with the Chalfont Seizure Severity Score. Regression analysis showed that elevated malondialdehyde is an independent risk factor for ADHD in children with epilepsy (OR: 1.401, 95%CI: 1.056-1.859, p= 0.02). No significant association was found between malondialdehyde and apelin levels and the type of epilepsy or ADHD. Longer duration of epilepsy, increased seizure severity, and uncontrolled seizures are associated with increased oxidation stress, which further increased susceptibility for ADHD. In spite of elevated apelin in children with ADHD, the elevation did not increase the risk of ADHD in children with epilepsy.

Comparison of cytokines and prooxidants/antioxidants markers among adults with refractory versus well-controlled epilepsy: A cross-sectional study

PURPOSE

This study aims to investigate the serum adiponectin, interleukin (IL)-6 and oxidative stress in epilepsy patients who are refractory or non-refractory to treatments.

METHOD

The study comprised 31 refractory epilepsy, 29 well-controlled epilepsy patients and control group including 29 healthy individuals. The serum adiponectin, IL-6, total antioxidant status (TAS), total oxidant status levels (TOS) and oxidative stress index (OSİ) were determined.

RESULTS

The mean serum adiponectin and TAS levels were significantly lower in the refractory epilepsy patients than in the healty controls, and mean IL-6, TOS and OSİ levels were significantly higher. The serum adiponectin, IL-6, TAS, TOS and OSI levels were not significantly different between the well-controlled epilepsy patients and the healthy controls.

CONCLUSIONS

The mean serum IL-6 and oxidative stress levels in refractory epilepsy patients were higher and the serum adiponectin level was lower than the healthy control group. These findings may be associated with an increased risk of seizures, atherosclerosis and cardiovascular disease in refractory epilepsy patients.

Oxidative Stress in Patients with Drug Resistant Partial Complex Seizure

Oxidative stress (OS) has been implicated as a pathophysiological mechanism of drug-resistant epilepsy, but little is known about the relationship between OS markers and clinical parameters, such as the number of drugs, age onset of seizure and frequency of seizures per month. The current study’s aim was to evaluate several oxidative stress markers and antioxidants in 18 drug-resistant partial complex seizure (DRPCS) patients compared to a control group (age and sex matched), and the results were related to clinical variables. We examined malondialdehyde (MDA), advanced oxidation protein products (AOPP), advanced glycation end products (AGEs), nitric oxide (NO), uric acid, superoxide dismutase (SOD), glutathione, vitamin C, 4-hydroxy-2-nonenal (4-HNE) and nitrotyrosine (3-NT). All markers except 4-HNE and 3-NT were studied by spectrophotometry. The expressions of 4-HNE and 3-NT were evaluated by Western blot analysis. MDA levels in patients were significantly increased (p ≤ 0.0001) while AOPP levels were similar to the control group. AGEs, NO and uric acid concentrations were significantly decreased (p ≤ 0.004, p ≤ 0.005, p ≤ 0.0001, respectively). Expressions of 3-NT and 4-HNE were increased (p ≤ 0.005) similarly to SOD activity (p = 0.0001), whereas vitamin C was considerably diminished (p = 0.0001). Glutathione levels were similar to the control group. There was a positive correlation between NO and MDA with the number of drugs. The expression of 3-NT was positively related with the frequency of seizures per month. There was a negative relationship between MDA and age at onset of seizures, as well as vitamin C with seizure frequency/month. We detected an imbalance in the redox state in patients with DRCPS, supporting oxidative stress as a relevant mechanism in this pathology. Thus, it is apparent that some oxidant and antioxidant parameters are closely linked with clinical variables.

Anxiolytic effect of anacardic acids from cashew (Anacardium occidentale) nut shell in mice

Antianxiety drugs currently in use are associated with a number of serious side effects. Present study was designed to evaluate the efficacy of anacardic acids (AAs) isolated from cashew nut (Anacardium occidentale L.) shell liquid (CNSL) to treat anxiety as well as its role in oxidative stress in mice model. Anxiolytic effect of AA was evaluated using rota-rod and a set of behavioral tests in male Swiss albino mice at the doses of 10, 25, and 50 mg/kg. Flumazenil was used to evaluate the possible involvement of GABAergic system in the mechanism of action of AA. The effect of AA on oxidative stress in mice was evaluated by determining the concentration of malondialdehyde (MDA), reduced glutathione, and catalase (CAT) activity. The detection of DNA damage of the treated animals was performed using alkaline comet test in the hippocampus and frontal cortex of the animals. The results demonstrated that AA did not produce myorelaxant and sedative effects, nor did it cause a decrease in locomotor activity. The anxiolytic effect of AA was well-evident in all tests, especially at higher dose levels (25 and 50 mg/mg). Flumazenil reversed the anxiolytic effect of AA at all doses. In addition, AA reduced oxidative stress by decreasing the concentration of MDA and increasing the levels of reduced glutathione (GSH) and CAT activity. Statistical analysis by Pearson's correlation indicated a positive correlation between anxiolytic effect of AA to its antioxidant and lipid peroxidation inhibitory activity. Furthermore, increased CAT activity and GSH concentrations in the hippocampus and frontal cortex of mice was also complementary to the reduced genotoxic damage observed in the study. In comet assay, AA did not increase in DNA damage. In conclusion, the results supported that AA possesses GABA_A receptor mediated anxiolytic activity with the lack of myorelaxation and genotoxicity. © 2018 IUBMB Life, 70(5):420-431, 2018.

Resveratrol for Easing Status Epilepticus Induced Brain Injury, Inflammation, Epileptogenesis, and Cognitive and Memory Dysfunction-Are We There Yet?

Status epilepticus (SE) is a medical emergency exemplified by self-sustaining, unceasing seizures or swiftly recurring seizure events with no recovery between seizures. The early phase after SE event is associated with neurodegeneration, neuroinflammation, and abnormal neurogenesis in the hippocampus though the extent of these changes depends on the severity and duration of seizures. In many instances, over a period, the initial precipitating injury caused by SE leads to temporal lobe epilepsy (TLE), typified by spontaneous recurrent seizures, cognitive, memory and mood impairments associated with chronic inflammation, reduced neurogenesis, abnormal synaptic reorganization, and multiple molecular changes in the hippocampus. While antiepileptic drugs are efficacious for terminating or greatly reducing seizures in most cases of SE, they have proved ineffective for easing SE-induced epileptogenesis and TLE. Despite considerable advances in elucidating SE-induced multiple cellular, electrophysiological, and molecular changes in the brain, efficient strategies that prevent SE-induced TLE development are yet to be discovered. This review critically confers the efficacy and promise of resveratrol, a phytoalexin found in the skin of red grapes, for easing SE-induced neurodegeneration, neuroinflammation, aberrant neurogenesis, and for restraining the evolution of SE-induced brain injury into a chronic epileptic state typified by spontaneous recurrent seizures, and learning, memory, and mood impairments.

Anticonvulsant and Antioxidant Effects of Pitavastatin Against Pentylenetetrazol-Induced Kindling in Mice

Purpose: The pleiotropic effects of statins (antioxidant and anti-inflammation) have been reported by previous studies. Therefore, we aimed to determine whether pitavastatin has protective effects against pentylenetetrazol (PTZ)-induced kindling in mice and also whether pitavastatin improves the brain antioxidant capacity and attenuates the oxidative injuries in kindled mice.

Methods: Twenty-four mice were randomly divided into four groups (each group n=6); control, PTZ-kindling and PTZ-kindled rats treated with pitavastatin (1&4 mg/kg). PTZ kindling seizures were induced by repetitive intraperitoneal injections of PTZ (65 mg/kg) every 48 hours till day twenty-one. Animals received daily oral pitavastatin for twenty-one days. Latency, score and duration of the seizures were recorded. The activities of catalase (CAT) ad superoxide dismutase (SOD), and likewise the contents of malondialdehyde (MDA) and nitrate were assessed in the brains of all rats.

Results: There was a progressive reduction in latency of the kindled rats in the next injections of PTZ. Pitavastatin reduced this value (latency) particularly at higher dose. Seizures duration and score also decreased in treatment groups. SOD and CAT activities significantly decreased in PTZ-kindling group by 62% and 64%, respectively, but pitavastatin did not significantly change the SOD and CAT activities. Brain MDA and nitrate significantly increased in PTZ-kindling group by 53% and 30%, respectively. Pitavastatin at higher dose significantly decreased the MDA and nitrate contents of PTZ-kindling rats by 45% and 32%, respectively.

Conclusion: Our findings revealed that pitavastatin can improve the behavioral expression of the PTZ-kindling rats and attenuate the seizure-induced oxidative/nitrosative damage.

Anticonvulsant effect of ethanolic extract of Cyperus articulatus L. leaves on pentylenetetrazol induced seizure in mice

Cyperus articulatus (CA) rhizomes have demonstrated different properties on nervous system. However, the leaves still have not studied to treat epilepsy. The aim of this study was to determine the effect of CA ethanolic extract on pentylenetetrazol (PTZ) induced seizures in mice as well as measuring its antioxidant activity in vivo and in vitro. Mice were divided into five groups: (1) control (PTZ 80 mg/kg; i.p.), (2) PTZ-Diazepam (1 mg/kg; i.p.), (3-5) PTZ-CA 50, PTZ-CA 150 and PTZ-CA 300 (50, 150 and 300 mg/kg of CA extract, 30 min prior to each PTZ injection). The PTZ-CA 150 group showed lower seizure scores (P < 0.01), latency (P < 0.01), frequency (P < 0.01) and duration (P < 0.01) than control group. The antioxidant activity of CA extract scavenged DPPH radical showed IC 50 = 16.9 ± 0.1 μg/mL and TEAC = 2.28 ± 0.08, mmol trolox/g of extract, the content of gamma amino butyric acid (GABA) and malondialdehyde (MDA) were significantly high (P < 0.01) at dose of 150 mg/kg (82 ± 1.2 ng/g tissue; 1.0 ± 2.2 mol/g tissue, respectively). The present research demonstrated that CA extract possesses a potential effect to prevent PTZ induced seizures, antioxidant activity in addition to increase GABA levels.

Effect of Oxidative Stress on ABC Transporters: Contribution to Epilepsy Pharmacoresistance

Epilepsy is a neurological disorder affecting around 1%–2% of population worldwide and its treatment includes use of antiepileptic drugs to control seizures. Failure to respond to antiepileptic drug therapy is a major clinical problem and over expression of ATP-binding cassette transporters is considered one of the major reasons for pharmacoresistance. In this review, we have summarized the regulation of ABC transporters in response to oxidative stress due to disease and antiepileptic drugs. Further, ketogenic diet and antioxidants were examined for their role in pharmacoresistance. The understanding of signalling pathways and mechanism involved may help in identifying potential therapeutic targets and improving drug response.

Selenium in the Therapy of Neurological Diseases. Where is it Going?

Selenium (₃₄Se), an antioxidant trace element, is an important regulator of brain function. These beneficial properties that Se possesses are attributed to its ability to be incorporated into selenoproteins as an amino acid. Several selenoproteins are expressed in the brain, in which some of them, e.g. glutathione peroxidases (GPxs), thioredoxin reductases (TrxRs) or selenoprotein P (SelP), are strongly involved in antioxidant defence and in maintaining intercellular reducing conditions. Since increased oxidative stress has been implicated in neurological disorders, including Parkinson’s disease, Alzheimer’s disease, stroke, epilepsy and others, a growing body of evidence suggests that Se depletion followed by decreased activity of Se-dependent enzymes may be important factors connected with those pathologies. Undoubtedly, the remarkable progress that has been made in understanding the biological function of Se in the brain has opened up new potential possibilities for the treatment of neurological diseases by using Se as a potential drug. However, further research in the search for optimal Se donors is necessary in order to achieve an effective and safe therapeutic income.

Glycyrrhizin ameliorates oxidative stress and inflammation in hippocampus and olfactory bulb in lithium/pilocarpine-induced status epilepticus in rats

Glycyrrhizin (GL) is a triterpene present in the roots and rhizomes of Glycyrrhiza glabra that has anti-inflammatory, hepatoprotective and neuroprotective effects. Recently, it was demonstrated that GL produced neuroprotective effects on the postischemic brain as well as on the kainic acid injury model in rats. In addition to this, GL also prevented excitotoxic effects on primary cultures. The aims of the present study were to evaluate GL scavenging properties and to investigate GL's effect on oxidative stress and inflammation in the lithium/pilocarpine-induced seizure model in two cerebral regions, hippocampus and olfactory bulb, at acute time intervals (3 or 24h) after status epilepticus (SE). Fluorometric methods showed that GL scavenged three reactive oxygen species: hydrogen peroxide, peroxyl radicals and superoxide anions. In contrast, GL was unable to scavenge peroxynitrite, hydroxyl radicals, singlet oxygen and 2,2-diphenil-1-picrylhydrazyl (DPPH) radicals suggesting that GL is a weak scavenger. Additionally, administration of GL (50mg/kg, i.p.) 30min before pilocarpine administration significantly suppressed oxidative stress. Moreover, malondialdehyde levels were diminished and glutathione levels were maintained at control values in both cerebral regions at 3 and 24 after SE. At 24h after SE, glutathione S-transferase and superoxide dismutase activity increased in the hippocampus, while both glutathione reductase and glutathione peroxidase activity were unchanged in the olfactory bulb at that time. In addition, GL suppressed the induction of the proinflammatory cytokines interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) in both cerebral regions evaluated. These results suggest that GL confers protection against pilocarpine damage via antioxidant and anti-inflammatory effects.

Oxidative Stress Measurement and Prediction of Epileptic Seizure in Children and Adults With Severe Motor and Intellectual Disabilities

BACKGROUND

The medical care of severe motor and intellectual disabilities (SMID) depends on the empirical medical care. Epileptic seizure specific to SMID is difficult to suppress using anti-epileptic drugs, and its tendency to persist for long periods poses an issue. The present study was undertaken to evaluate the relationship between epileptic seizure in cases with SMID and oxidative stress in the living body by examining endogenous antioxidants, the degree of oxidation (reactive oxygen metabolites (d-ROMs)), and the biological antioxidant potential (BAP) as indicators.

METHODS

Target patients were 43 SMID epilepsy patients. Blood was sampled before breakfast and medication. As for the specimen, d-ROMs and BAP were measured using the free radical analyzer.

RESULTS

The present study did not reveal any correlation between endogenous antioxidants (albumin) and the frequency of epileptic seizures. On the other hand, d-ROMs were correlated with the frequency of epileptic seizure. In particular, strong correlations between the frequency of epileptic seizures and the d-ROMs/BAP ratio as well as the BAP/d-ROMs ratio were noted.

CONCLUSIONS

These results indicate that the use of d-ROMs and BAP as biomarkers can provide a tool for predicting the prognosis of epileptic seizures in patients with SMID.

Blood oxidative stress and metallothionein expression in Rett syndrome: Probing for markers

OBJECTIVES

Oxidative stress seems to be involved in Rett syndrome (RTT). The aim of this study was to assess the antioxidant status in RTT children with MECP2 gene mutations with respect to healthy controls, and to explore novel blood antioxidant markers for RTT severity.

METHODS

In erythrocytes from RTT females aged 2-14 years (n = 27) and age-matched controls (n = 27), we measured the levels of malonaldehyde and the activity of two antioxidant enzymes, Cu/Zn-superoxide dismutase and catalase, by spectrophotometric assays. In leukocytes, the expression of metallothioneins, the main non-enzymatic antioxidants, was assessed by real-time RT-PCR. In nine selected RTT children, methylome analysis was also performed.

RESULTS

Blood of RTT patients showed increased lipid peroxidation and a dysregulated pattern of MT expression, while enzymatic activities did not change significantly with respect to controls. Moreover, we observed no epigenetic dysregulation in CpG-enriched promoter regions of the analysed genes but significant hypomethylation in the random loci.

CONCLUSIONS

As the haematic level of MT-1A directly correlates with the phenotype severity, this metallothionein can represent a marker for RTT severity. Moreover, the attempt to link the level of blood oxidative stress with MECP2 mutation and specific clinical features led us to draw some interesting conclusions.