Levetiracetam protects against kainic acid-induced toxicity

Oligoprotective Activity of Levetiracetam against Glutamate Toxicity: An In vitro Study

INTRODUCTION

The role of glutamate in the development of some brain pathological conditions, such as multiple sclerosis, has been well described. Levetiracetam (LEV), a new broad-spectrum antiseizure medicine, is widely used to control certain types of seizures. Apart from its anti-seizure activity, LEV exerts neuroprotection via anti-inflammatory, antioxidant, and antiapoptotic effects. The current study was designed to evaluate the protective potential of LEV against glutamate-induced injury in OLN-93 oligodendrocytes.

METHODS

At first, the potential negative impact of LEV on OLN-93 viability was evaluated. After that, the cells were concurrently treated with LEV (0-100 μM) and glutamate (8 mM) for 24 h. The viability, redox status, and the rate of apoptosis of OLN-93 cells were then assessed using 3-[4,5-dimethylthiazol- 2-yl]-2,5-diphenyl-2H-tetrazolium bromide (MTT), 2',7' dichlorodihydrofluorescein diacetate (H2DCFDA), 2-thiobarbituric acid reactive substances (TBARS) and annexin V/propidium iodide (PI) assays, respectively. Moreover, caspase-3 expression, as a marker of cell apoptosis, was evaluated by Western blotting.

RESULTS

LEV at 1-800 μM did not have any negative effect on cell survival. Treatment with LEV (50 and 100 μM) substantially enhanced the cell viability following glutamate insult. The cytoprotective activity of LEV (50 and 100 μM) against glutamate toxicity was accompanied by reduced reactive oxygen species (ROS) accumulation and malondialdehyde (MDA) level. Moreover, 100 μM of LEV inhibited apoptosis and decreased the expression level of cleaved caspase-3 following glutamate exposure.

CONCLUSION

Taken together, the results suggested that LEV has protective effects against glutamate-mediated cytotoxicity in OLN-93 cells. The oligoprotective action of LEV was shown to be exerted via inhibition of oxidative stress and cellular apoptosis.

Impact of levetiracetam and ethanol on memory, selected neurotransmitter levels, oxidative stress parameters, and essential elements in rats

BACKGROUND

Ethanol disrupts brain activity and memory. There is evidence supporting the beneficial effect of levetiracetam on alcohol consumption. Therefore, the aim of the study was to examine whether levetiracetam has a protective activity against ethanol-induced memory impairment, alterations in selected neurotransmission activities, oxidative stress, and selected essential elements in rats.

METHODS

The rats were given levetiracetam (300 mg/kg b.w. po) with ethanol for three weeks prior to behavioral tests. Spatial memory was tested using the Morris water maze, while recognition memory was evaluated using the Novel object recognition test. The GABA and glutamate concentration was determined in three rat brain regions (cerebellum, hippocampus, and cerebral cortex). Serum oxidative stress parameters and selected essential elements concentration (Cu, Mn, Zn, Fe, Mg) in the rat brain were analyzed.

RESULTS

Levetiracetam administered with ethanol improved spatial memory, but did not affect abstinence-induced impairment. The drug also decreased ethanol-induced long-term recognition memory impairment. No alterations in glutamate levels were observed. GABA levels were elevated by levetiracetam in the cerebral cortex and by ethanol in the cerebellum. Ethanol increased catalase activity (CAT) and decreased superoxide dismutase activity (SOD) in the serum. Levetiracetam significantly increased the activity of SOD. Alcohol disrupted the levels of trace elements (Mn, Zn, Mg) in the rat brain. Additionally, levetiracetam alone increased Mg, Fe, and Cu concentrations while all animals receiving the drug also had significantly lower concentrations of Zn.

CONCLUSIONS

Levetiracetam had differential effects against ethanol-induced impairments. These findings could have important implications for future levetiracetam treatment in patients.

Therapeutic Effect of Levetiracetam Against Thioacetamide-Induced Hepatic Encephalopathy Through Inhibition of Oxidative Stress and Downregulation of NF-κB, NLRP3, iNOS/NO, Pro-Inflammatory Cytokines and Apoptosis

Hepatic encephalopathy (HE) is a serious brain disorder which associated with neurological and psychiatric manifestations. Oxidative stress and neuroinflammation and apoptosis play main roles in the development of brain damage in HE. Levetiracetam is an antiseizure drug with established antioxidant and anti-inflammatory activities. In the present study we investigated the therapeutic effects of levetiracetam against brain injury in HE and its underlying mechanisms of action. Male C57BL/6 mice were subjected to the induction of HE by the injection of thioacetamide (200 mg/kg) for 2 days. Mice were treated with levetiracetam at two doses (50 or 100 mg/kg/day) for 3 days in the treatment groups. Animals were subjected to a behavioral test and the brain tissues were dissected for histopathological, biochemical, gene expression and immunofluorescence analysis. The results showed that levetiracetam alleviated body weight loss and improved locomotor activity of mice with HE. Levetiracetam treatment decreased the histopathological changes, lipid peroxidation and protein carbonylation while restored the antioxidants (GSH, SOD and CAT) in the brain. Levetiracetam decreased the expression and activity of NF-κB, NOD-like receptor pyrin domain-containing protein 3 (NLRP3) and pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, and IFN-γ) in the brain tissue. Administration of levetiracetam inhibited iNOS/NO pathway and myeloperoxidase (MPO) activity in the brain. Moreover, caspase-3 was decreased and the ratio of Bcl2/Bax was increased in the brain of mice treated with levetiracetam. These findings suggest that levetiracetam may be a promising therapeutic agent for brain injury in HE through inhibiting the oxidative, inflammatory and apoptotic pathways.

Oxidative Stress and Neurodegeneration in Animal Models of Seizures and Epilepsy

Free radicals are generated in the brain, as well as in other organs, and their production is proportional to the brain activity. Due to its low antioxidant capacity, the brain is particularly sensitive to free radical damage, which may affect lipids, nucleic acids, and proteins. The available evidence clearly points to a role for oxidative stress in neuronal death and pathophysiology of epileptogenesis and epilepsy. The present review is devoted to the generation of free radicals in some animal models of seizures and epilepsy and the consequences of oxidative stress, such as DNA or mitochondrial damage leading to neurodegeneration. Additionally, antioxidant properties of antiepileptic (antiseizure) drugs and a possible use of antioxidant drugs or compounds in patients with epilepsy are reviewed. In numerous seizure models, the brain concentration of free radicals was significantly elevated. Some antiepileptic drugs may inhibit these effects; for example, valproate reduced the increase in brain malondialdehyde (a marker of lipid peroxidation) concentration induced by electroconvulsions. In the pentylenetetrazol model, valproate prevented the reduced glutathione concentration and an increase in brain lipid peroxidation products. The scarce clinical data indicate that some antioxidants (melatonin, selenium, vitamin E) may be recommended as adjuvants for patients with drug-resistant epilepsy.

Levetiracetam attenuates experimental ulcerative colitis through promoting Nrf2/HO-1 antioxidant and inhibiting NF-κB, proinflammatory cytokines and iNOS/NO pathways

Ulcerative colitis (UC) is a serious inflammatory disease of the colon. The pathogenic mechanisms of UC involve the activation of inflammatory and oxidative stress responses in the colon. Levetiracetam is an antiepileptic drug with anti-inflammatory and antioxidant effects. The aim of this study was to investigate the potential protective effect of levetiracetam against UC in a mouse model. UC was induced in mice by intrarectal administration of acetic acid and then mice were treated with levetiracetam (50 or 100 mg/kg/day, i.p.) for three days. The colonic tissue samples were dissected for biochemical, RT-PCR and immunofluorescence analysis. Results showed that levetiracetam treatment significantly decreased colonic mucosal injury as evidenced by the macroscopic and histopathological analysis. Levetiracetam induced Nrf2/HO-1 and antioxidants while reduced lipid peroxidation and myeloperoxidase activity in colon tissue. Levetiracetam treatment decreased NF-κB activity and the expression of proinflammatory mediators TNF-α, IL-6, IL-1β, IFN-γ, MCP-1 and ICAM-1. The colonic levels of anti-inflammatory cytokines IL-10 and TGF-β1 were increased by levetiracetam treatment. Furthermore, levetiracetam significantly diminished iNOS expression and NO production in colon tissue. These findings suggest that levetiracetam ameliorates the severity of UC in mice through the regulation of inflammatory and oxidative responses.

The differential effect of levetiracetam on memory and anxiety in rats

OBJECTIVE

One of the newest antiseizure medication is levetiracetam (LEV). It might be effective in various indications, not only related to convulsions. Central nervous system disorders are common during anticonvulsant therapy. The aim of this study was to assess the effect of LEV on various types of memory and anxiety in rats.

METHODS

Adult male Wistar rats (n = 58) were given LV p.o. as a single (100 mg/kg or 500 mg/kg) or repeated doses (300 mg/kg). The effect of the drug on memory was assessed in the Morris water maze (MWM) (spatial memory), the passive avoidance (PA) (emotional memory) and the novel object recognition (NOR) (recognition memory). The anxiety was evaluated in the elevated plus maze (EPM).

RESULTS

LEV administered as repeated doses disturbed the long-term recognition memory in NOR and locomotor activity in EPM. A single dose affected emotional memory in PA. LEV did not alter spatial memory in MWM.

CONCLUSIONS

LEV may cause memory and locomotor disturbances, but some of these adverse effects seem to be temporary and limited to the effect of acute dose.

Beneficial effects of levetiracetam in streptozotocin-induced rat model of Alzheimer's disease

Alzheimer's disease (AD) is the most common neurodegenerative disorder among the elderly. In the light of increasing AD prevalence and lack of effective treatment, new strategies to prevent or reverse this condition are needed. Levetiracetam (LEV) is a newer antiepileptic drug that is commonly used to treat certain types of seizures. Researches indicated that LEV has several other pharmacological activities, including improvement of cognitive function. In this study, the recovery effects of chronic (28 days) administration of LEV (50, 100, and 150 mg/kg, ip) on cognitive deficits caused by the intracerebroventricular (icv) injection of streptozotocin (STZ), as a model for sporadic AD, were evaluated in rats. We also considered the protective effects of LEV against hippocampal cell loss, oxidative damage, acetylcholinesterase (AChE) activity, neuroinflammation, and tauopathy caused by STZ. LEV (100 and 150 mg/kg) significantly attenuated the STZ-induced learning and memory impairments in the passive avoidance and Morris water maze (MWM) tasks. In addition, LEV suppressed STZ-induced hippocampal neuronal loss, while restored alterations in the redox status (lipid peroxides and glutathione), AChE activity, proinflammatory cytokines (IL-1β, IL-6, TNF-α), and hyperphosphorylation of tau linked to STZ administration. In conclusion, our study demonstrated that LEV alleviated hippocampal cell death and memory deficits in STZ-AD rats, through mitigating oxidative damage, suppression of proinflammatory cytokines expression, and inhibition of abnormal tau hyperphosphorylation.

Preparation of Nanocrystals for Insoluble Drugs by Top-Down Nanotechnology with Improved Solubility and Bioavailability

Midazolam is a rapidly effective benzodiazepine drug that is widely used as a sedative worldwide. Due to its poor solubility in a neutral aqueous solution, the clinical use of midazolam is significantly limited. As one of the most promising formulations for poorly water-soluble drugs, nanocrystals have drawn worldwide attention. We prepared a stable nanosuspension system that causes little muscle irritation. The particle size of the midazolam nanocrystals (MDZ/NCs) was 286.6 ± 2.19 nm, and the crystalline state of midazolam did not change in the size reduction process. The dissolution velocity of midazolam was accelerated by the nanocrystals. The pharmacokinetics study showed that the AUC0-t of the MDZ/NCs was 2.72-fold (p < 0.05) higher than that of the midazolam solution (MDZ/S), demonstrating that the bioavailability of the MDZ/NC injection was greater than that of MDZ/S. When midazolam was given immediately after the onset of convulsions, the ED50 for MDZ/NCs was significantly more potent than that for MDZ/S and DZP/S. The MDZ/NCs significantly reduced the malondialdehyde content in the hippocampus of the seizures model rats and significantly increased the glutathione and superoxide dismutase levels. These results suggest that nanocrystals significantly influenced the dissolution behavior, pharmacokinetic properties, anticonvulsant effects, and neuroprotective effects of midazolam and ultimately enhanced their efficacy in vitro and in vivo.

[Assessment of neurodevelopment in children of different gestational age with neonatal seizures]

AIM

To assess psychomotor development in infants with neonatal seizures (NS) born with different gestational age, by means of Bayley-III scales of infant and toddler development, in their corrected age of 1 year.

MATERIAL AND METHODS

The study included 52 infants, who had NS and were born with different gestational age: 28 weeks or less (n=26) - group I, 29-32 weeks (n=16) - group II, 33-36 weeks (n=3) - group III, 37-41 weeks (n=7) - group IV. The infants' neurodevelopment was evaluated in their corrected age of 1 year by means of N. Bayley scales of infant and toddler development, third edition: Cognitive, Language, Motor, Social-Emotional, and Adaptive Behavior.

RESULTS AND CONCLUSION

Only 17 (32,7%) of 52 examined infants did not demonstrate any developmental delay on each of five Bayley-III scales. Significant developmental delay (composite score <70) on at least one scale was revealed in 23 (44,2%) patients, including 12 (46,2%) in group I, 5 (31,3%) in group II, 6 (60%) of 10 in the combined group III-IV. In most cases, neurodevelopmental delays were attributed to only one domain and could be indicated as partial. The conclusion about global developmental retardation (the composite scores 55 or less on all five scales) was done in 3 patients, each of whom had a co-morbidity of cerebral palsy and epilepsy.

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.

Neuroprotective Effects of Polydeoxyribonucleotide in a Murine Model of Cadmium Toxicity

Cadmium (Cd) is a harmful heavy metal, which causes severe brain damage and neurotoxic effects. Polydeoxyribonucleotide (PDRN) stimulates adenosine A_2A receptor, thus contrasting several deleterious mechanisms in course of tissue damages. We aimed to investigate the possible neuroprotective effect of PDRN in a murine model of Cd-induced brain toxicity. Male C57 BL/6J mice were treated as follows: vehicle (0.9% NaCl, 1 ml/kg/day), PDRN (8 mg/kg/day), CdCl₂ (2 mg/kg/day), and CdCl₂ + PDRN. Animals were tested with the Morris water maze test to assess spatial memory and learning. After 14 days of treatment, brains were processed to evaluate the presence of edema in the cerebral tissue, the expression of mammalian target of rapamycin kinase (mTOR) and brain-derived neurotrophic factor (BDNF), and the morphological behavior of the hippocampal structures. After CdCl₂ administration, the escape latency was high, protein expression of BDNF was significantly decreased if compared to controls, mTOR levels were higher than normal controls, and brain edema and neuronal damages were evident. The coadministration of CdCl₂ and PDRN significantly diminished the escape latency, increased BDNF levels, and decreased protein expression of mTOR. Furthermore, brain edema was reduced and the structural organization and the number of neurons, particularly in the CA1 and CA3 hippocampal areas, were improved. In conclusion, a functional, biochemical, and morphological protective effect of PDRN against Cd induced toxicity was demonstrated in mouse brain.

Does Levetiracetam Administration Prevent Cardiac Damage in Adulthood Rats Following Neonatal Hypoxia/Ischemia-Induced Brain Injury?

Cardiovascular abnormalities are widespread when a newborn is exposed to a hypoxic-ischemic injury in the neonatal period. Although the neuroprotective effects of levetiracetam (LEV) have been reported after hypoxia, the cardioprotective effects of LEV have not been documented. Therefore, we aimed to investigate whether levetiracetam (LEV) has a protective effect on cardiac-contractility and ultrastructure of heart muscle in rats exposed to hypoxia-ischemia (HI) during the neonatal period. A total of 49 seven-day-old rat pups were separated into four groups. For HI induction, a combination of right common carotid artery ligation with 8% oxygen in seven-day-old rat pups for 2 h was performed for saline, LEV100, and LEV200 groups. Just after hypoxia, LEV100 and LEV200 groups were administered with 100 mg/kg and 200 mg/kg of LEV, respectively. The arteries of rats in the control group were only detected; no ligation or hypoxia was performed. At the end of the 16th week after HI, cardiac mechanograms were recorded, and samples of tissue were explored by electronmicroscopy.While ventricular contractility in the control group was similar to LEV100, there were significant decreases in both saline and LEV200 groups (p < 0.05). Although ventricular contractile duration of the control and saline groups was found to be similar, durations in the LEV100 and LEV200 groups were significantly higher (p < 0.05). After HI, mitochondrial damage and ultrastructural deteriorative alterations in ventricles and atriums of the LEV-administered groups were significantly less severe than the saline group. The present study showed that neonatal HI caused long-term cardiac dysfunction and ultrastructural deteriorations in cardiac muscles. LEV administration just after HI might possess some protective effects against myocardial damage and contractility.

Efficacy of levetiracetam for neonatal seizures in preterm infants

Background

Neonatal seizures remain a significant clinical problem, and therapeutic options are still not diverse with limited efficacy. Levetiracetam (LEV) is a relatively new and wide spectrum anti-seizure medication with favorable pharmacokinetics and safety profile. In the recent decades, LEV has been increasingly used for the treatment of neonatal seizures. The aim of this study was to describe the experience of using LEV as the first line anti-seizure medication for preterm infants.

Methods

A retrospective analysis of 37 preterm infants who were treated with LEV as the first-line anti-seizure medication was performed.

Results

Mean gestational age of the 37 preterm infants was 31.5 ± 1.9 weeks (range, 26 to 36^+ 6 weeks). Twenty-one infants (57%) were seizure-free while given LEV at the end of the first week, and no additional anti-seizure medication was required. Loading doses of LEV ranged from 40 to 60 mg/kg (mean 56 mg/kg) and the maintenance dose ranged from 20 to 30 mg/kg (mean 23 mg/kg). No adverse effect was observed.

Conclusions

Levetiracetam can be a good and safe choice for treatment of neonatal seizures in preterm infants. Prospective double blind controlled studies are needed in the future.

Impact of Oxidative Stress and Newer Antiepileptic Drugs on the Albumin and Cortisol Value in Severe Motor and Intellectual Disabilities With Epilepsy

Background

Epilepsy is a common complication in patients with severe motor and intellectual disabilities (SMID). There are no reports as yet of the effects of these medications in vivo other than their epileptic efficacy. The purpose of this study was to clarify the effects of the newer antiepileptic drugs (AEDs) on the blood biochemical parameters and oxidative stress in SMID with epilepsy by comparing the therapeutic effects between a group of patients receiving lamotrigine (LTG) and levetiracetam (LEV) in addition to the conventional AEDs (newer AED group) and a group receiving conventional AEDs alone (old AED group).

Methods

The study population consisted of 44 SMID patients with epilepsy, of which 23 were allocated to the newer AED group and 21 were allocated to the old AED group. In the newer AED group, measurements of the reactive oxygen metabolites (d-ROMs), biological antioxidant potential (BAP) and serum albumin were carried out at the following two time points: 1 week before and 1 year after the start of administration of the newer AEDs. In the old AED group, measurements of the same variables were performed at two time points 1 year apart.

Results

A significant decrease of the d-ROM levels and a significant increase of the BAP were noted in the newer AED group. A significant elevation of the serum albumin was also evident. In the old AED group, a significant increase of the d-ROMs levels was noted at the second measurement. Cortisol levels which have been described to be related to the albumin, revealed a significant decrease of the serum cortisol in relation to elevation of serum albumin in the newer AED group.

Conclusions

The present study results suggest that the addition of newer AEDs reduces the oxidative stress load and improves the antioxidant potential of the body. Furthermore, the present data also demonstrate that the newer AEDs have indirect impact on biological parameters.

Divergent effects of levetiracetam and tiagabine against spontaneous seizures in adult rats following neonatal hypoxia

Animal models are valuable tools for screening novel therapies for patients who suffer from epilepsy. However, a wide array of models are necessary to cover the diversity of human epilepsies. In humans, neonatal hypoxia (or hypoxia-ischemia) is one of the most common causes of epilepsy early in life. Hypoxia-induced seizures (HS) during the neonatal period can also lead to spontaneous seizures in adulthood. This phenomenon, i.e., early-life hypoxia leading to adult epilepsy - is also seen in experimental models, including rats. However, it is not known which anti-seizure medications are most effective at managing adult epilepsy resulting from neonatal HS. Here, we examined the efficacy of three anti-seizure medications against spontaneous seizures in adult rats with a history of neonatal HS: (1) phenobarbital (PHB), the oldest epilepsy medicine still in use today; (2) levetiracetam (LEV); and (3) tiagabine (TGB). Both LEV and TGB are relatively new anticonvulsant drugs that are ineffective in traditional seizure models, but strikingly effective in other models. We found that PHB and LEV decreased seizures in adult rats with a history of HS, whereas TGB exacerbated seizures. These divergent drug effects indicate that the HS model may be useful for differentiating the clinical efficacy of putative epilepsy therapies.

The Antiepileptic Drug Levetiracetam Protects Against Quinolinic Acid-Induced Toxicity in the Rat Striatum

Levetiracetam (LVT) is a relatively novel antiepileptic drug (AED) known to act through binding with the synaptic vesicular 2A (SV2A) protein, thus modulating the presynaptic neurotransmitter release. The tryptophan metabolite quinolinic acid (QUIN) acts as an excitotoxin when its brain concentrations reach toxic levels under pathological conditions. Since increased neuronal excitability induced by QUIN recruits degenerative events in the brain, and novel AED is also expected to exert neuroprotective effects in their pharmacological profiles, in this work the effect of LVT (54 mg/kg, i.p., administered for seven consecutive days) was tested as a pretreatment against the toxicity evoked by the bilateral intrastriatal injection of QUIN (60 nmol/μl) to adult rats. QUIN increased the striatal levels of peroxidized lipids and carbonylated proteins as indexes of oxidative damage 24 h after its infusion. In addition, in synaptosomal fractions isolated from QUIN-lesioned rats 24 h after the toxin infusion, γ-aminobutyric acid (GABA) release was decreased, whereas glutamate (Glu) release was increased. QUIN also decreased motor activity and augmented the rate of cell damage at 7 days post-lesion. All these alterations were significantly prevented by pretreatment of rats with LVT. The results of this study show a neuroprotective role and antioxidant action of LVT against the brain damage induced by excitotoxic events.

Reproductive toxicity after levetiracetam administration in male rats: Evidence for role of hormonal status and oxidative stress

Levetiracetam (LEV) is an antiepileptic drug commonly used in the treatment of epilepsy because of its excellent safety profile in all age groups. It is remarkable that there are no studies evaluating the toxic effects of this drug on the male reproductive system, as it is commonly used in male patients of reproductive age. From this point of view, our aim was to evaluate the possible toxic effects of LEV on the male reproductive system. Therefore, LEV was administered to male rats orally at 50, 150, and 300 mg/kg for 70 consecutive days. At the end of this period, alterations to body and organ weights were calculated, and sperm concentration, motility, and morphology were investigated by a computer-assisted sperm analysis system. Sperm DNA damage was determined by comet assay and histopathological examination of the testes was carried out. Serum testosterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) levels were measured by ELISAs to determine the effects of hormonal status, while glutathione, superoxide dismutase, catalase, and malondialdehyde levels in the testes were measured by colorimetric assay kits to determine the role of oxidative status in potential toxicity. According to the results, sperm quality was decreased by LEV treatment in a dose-dependent manner. LEV induced significant DNA damage in the 150 and 300 mg/kg LEV-administered groups. Histopathology of the testes showed that LEV resulted in testicular injury in the 300 mg/kg LEV-administered group. Serum testosterone, FSH, and LH levels were significantly decreased in the 300 mg/kg LEV-administered group. Glutathione, superoxide dismutase, and catalase levels were significantly decreased in all experimental groups while malondialdehyde levels were significantly increased in 150 and 300 mg/kg LEV-administered groups. According to these results, it was determined that LEV administration decreased sperm quality and it was alleged that hormonal alteration and oxidative stress are potential contributors to reproductive toxicity.

Comparative studies on the effects of clinically used anticonvulsants on the oxidative stress biomarkers in pentylenetetrazole-induced kindling model of epileptogenesis in mice

BACKGROUND

Oxidative stress plays a key role in the pathogenesis of epilepsy and contributes in underlying epileptogenesis process. Anticonvulsant drugs targeting the oxidative stress domain of epileptogenesis may provide better control of seizure. The present study was carried out to investigate the effect of clinically used anti-epileptic drugs (AEDs) on the course of pentylenetetrazole (PTZ)-induced kindling and oxidative stress markers in mice.

METHODS

Six mechanistically heterogeneous anticonvulsants: phenobarbital, phenytoin, levetiracetam, pregabalin, topiramate, and felbamate were selected and their redox profiles were determined. Diazepam was used as a drug control for comparison. Kindling was induced by repeated injections of a sub-convulsive dose of PTZ (50 mg/kg, s.c.) on alternate days until seizure score 5 was evoked in the control kindled group. Anticonvulsants were administered daily. Following PTZ kindling, oxidative stress biomarkers were assessed in homogenized whole brain samples and estimated for the levels of nitric oxide, peroxide, malondialdehyde, protein carbonyl, reduced glutathione, and activities of nitric oxide synthase and superoxide dismutase.

RESULTS

Biochemical analysis revealed a significant increase in the levels of reactive oxygen species with a parallel decrease in endogenous anti-oxidants in PTZ-kindled control animals. Daily treatment with levetiracetam and felbamate significantly decreased the PTZ-induced seizure score as well as the levels of nitric oxide (p<0.001), nitric oxide synthase activity (p<0.05), peroxide levels (p<0.05), and malondialdehyde (p<0.05). Levetiracetam and felbamate significantly decreased lipid and protein peroxidation whereas topiramate was found to reduce lipid peroxidation only.

CONCLUSIONS

An AED that produces anticonvulsant effect by the diversified mechanism of action such as levetiracetam, felbamate, and topiramate exhibited superior anti-oxidative stress activity in addition to their anticonvulsant activity.

Dose-dependent effects of levetiracetam after hypoxia and hypothermia in the neonatal mouse brain

Perinatal asphyxia to the developing brain remains a major cause of morbidity. Hypothermia is currently the only established neuroprotective treatment available for term born infants with hypoxic-ischemic encephalopathy, saving one in seven to eight infants from developing severe neurological deficits. Therefore, additional treatments with clinically applicable drugs are indispensable. This study investigates a potential additive neuroprotective effect of levetiracetam combined with hypothermia after hypoxia-induced brain injury in neonatal mice. 9-day-old C57BL/6-mice (P9) were subjected either to acute hypoxia or room-air. After 90min of systemic hypoxia (6% O2), pups were randomized into six groups: 1) vehicle, 2) low-dose levetiracetam (LEV), 3) high-dose LEV, 4) hypothermia (HT), 5) HT combined with low-dose LEV and 6) HT combined with high-dose LEV. Pro-apoptotic factors, neuronal structures, and myelination were analysed by histology and on protein level at appropriate time points. On P28 to P37 long-term outcome was assessed by neurobehavioral testing. Hypothermia confers acute and long-term neuroprotection by reducing apoptosis and preservation of myelinating oligodendrocytes and neurons in a model of acute hypoxia in the neonatal mouse brain. Low-dose LEV caused no adverse effects after neonatal hypoxic brain damage treated with hypothermia whereas administration of high-dose LEV alone or in combination with hypothermia increased neuronal apoptosis after hypoxic brain injury. LEV in low- dosage had no additive neuroprotective effect following acute hypoxic brain injury.

Neuroprotective effects of chronic administration of levetiracetam in a rat model of diabetic neuropathy

OBJECTIVE

Diabetic neuropathy (DNP) is a frequent and serious complication of diabetes mellitus (DM) that leads to progressive and length-dependent loss of peripheral nerve axons. The purpose of the present study is to assess the neuroprotective effects of levetiracetam (LEV) on DNP in a streptozotocin (STZ)-induced DM model in rats.

METHODS

Adult Sprague-Dawley rats were administered with STZ (60mg/kg) to induce diabetes. DNP was confirmed by electromyography (EMG) and motor function test on 21st day following STZ injection. Study groups were assigned as follows; Group 1: Naïve control (n=8), Group 2: DM+1mL/kg saline (n=12), Group 3: DM+300mg/kg LEV (n=10), Group 4: DM+600mg/kg LEV (n=10). LEV was administered i.p. for 30 consecutive days. Then, EMG, motor function test, biochemical analysis (plasma lipid peroxides and total anti-oxidant capacity), histological and immunohistochemical analysis of sciatic nerves (TUNEL assay, bax, caspase 3, caspase 8 and NGF) were performed to evaluate the efficacy of LEV.

RESULTS

Treatment of diabetic rats with LEV significantly attenuated the inflammation and fibrosis in sciatic nerves and prevented electrophysiological alterations. Immunohistochemistry of sciatic nerves showed a considerable increase in bax, caspase 3 and caspase 8 and a decrease in NGF expression in saline-treated rats whereas LEV significantly suppressed apoptosis markers and prevented the reduction in NGF expression. Besides, LEV considerably reduced plasma lipid peroxides and increased total anti-oxidant capacity in diabetic rats.

CONCLUSIONS

The results of the present study suggest that LEV may have therapeutic effects in DNP through modulation of anti-oxidant and anti-apoptotic pathways.

Levetiracetam attenuates rotenone-induced toxicity: A rat model of Parkinson's disease

Levetiracetam (LEV), a second-generation anti-epileptic drug, is used for treatment of both focal and generalized epilepsy. Growing body of evidence suggests that LEV may have neuroprotective effects. The present study was undertaken to investigate the neuroprotective effects of LEV on rotenone-induced Parkinson's disease (PD) in rats. Twenty-four adult Sprague-Dawley rats were infused with rotenone (3 μg/μl in DMSO) or vehicle (1 μl DMSO) into the left substantia nigra pars compacta (SNc) under stereotaxic surgery. PD model was assessed by rotational test ten days after drug infusion. The valid PD rats were randomly distributed into two groups; Group 1 (n=8) and Group 2 (n=8) were administered saline (1 ml/kg/day, i.p.) and LEV (600 mg/kg/day, i.p.) through 21 days, respectively. The effects of LEV treatment were evaluated by behavioral (rotation score), biochemical (brain homovalinic acid level and oxidant/antioxidant status) and immunohistochemical (tyrosine hydroxylase) parameters. Apomorphine-induced rotations in PD rats were significantly suppressed by LEV treatment. While unilateral rotenone lesion induced a dramatic loss of dopaminergic neurons both in the striatum and SNc, LEV treatment significantly attenuated the degenerative changes in dopaminergic neurons. Furthermore, LEV significantly decreased lipid peroxide levels, a marker of lipid peroxidation, and induced glutathione levels, catalase and superoxide dismutase activity in PD rats compared with saline group. We conclude that LEV may have beneficial effects on dopaminergic neurons against rotenone-induced injury. The underlying mechanism may be associated with the attenuation of oxidative stress.

Neuroprotection as a Potential Therapeutic Perspective in Neurodegenerative Diseases: Focus on Antiepileptic Drugs

Neuroprotection is conceived as one of the potential tool to prevent or slow neuronal death and hence a therapeutic hope to treat neurodegenerative diseases, like Parkinson's and Alzheimer's diseases. Increase of oxidative stress, mitochondrial dysfunction, excitotoxicity, inflammatory changes, iron accumulation, and protein aggregation have been identified as main causes of neuronal death and adopted as targets to test experimentally the putative neuroprotective effects of various classes of drugs. Among these agents, antiepileptic drugs (AEDs), both the old and the newer generations, have shown to exert protective effects in different experimental models. Their mechanism of action is mediated mainly by modulating the activity of sodium, calcium and potassium channels as well as the glutamatergic and GABAergic (gamma-aminobutyric acid) synapses. Neurological pathologies in which a neuroprotective action of AEDs has been demonstrated in specific experimental models include: cerebral ischemia, Parkinson's disease, and Alzheimer's disease. Although the whole of experimental data indicating that neuroprotection can be achieved is remarkable and encouraging, no firm data have been produced in humans so far and, at the present time, neuroprotection still remains a challenge for the future.

Omega 3 polyunsaturated fatty acids enhance the protective effect of levetiracetam against seizures, cognitive impairment and hippocampal oxidative DNA damage in young kindled rats

Levetiracetam (LEV) is a unique, effective, relatively safe antiepileptic drug that preferentially interacts with synaptic vesicle protein 2A (SV2A). This study aimed to explore the effect of combined treatment of LEV with omega 3 (OM3) on cognitive impairment and hippocampal oxidative stress and DNA damage induced by seizures in the PTZ-kindled young rat model. Cognitive functions, biomarkers of oxidative stress, and DNA damage were assessed in PTZ-kindled young rats pretreated with single and combined treatment of LEV (30mg/kg, i.p.) and OM3 (200mg/kg, p.o.). Pretreatment with LEV and OM3 at the tested doses significantly attenuated PTZ-induced seizures and decreased cognitive impairment in both passive avoidance and elevated plus maze tests in the PTZ-kindled rats. Moreover, the increase in hippocampal glutamate, malondialdehyde and 8-hydroxy-2-deoxyguanosine (8-OHdG) levels, as well as the decrease in reduced glutathione (GSH) levels and GSH-peroxidase and superoxide dismutase activities induced by PTZ kindling, significantly decreased. These effects were higher with combined treatment of LEV with OM3 and significantly more than the observed effects of single LEV or OM3. In conclusion, the combined treatment of LEV with OM3 is more effective in seizure control and alleviating the cognitive impairment induced by PTZ kindling in the young rat model, the effects that result from the decrease in hippocampal oxidative stress and DNA damage which can be attributed to the antioxidant properties of both LEV and OM3. These results may be promising for the use of LEV and OM3 combination in the treatment of epileptic children.

Levetiracetam ameliorates ovarian function in streptozotocin-induced diabetic rats

Diabetes mellitus can adversely affect gonadal function. In the present study, we aimed to investigate the protective effects and mechanism of action of levetiracetam (LEV) on the ovaries in a streptozotocin (STZ)-induced diabetes model in rats. Twenty-one adult female rats were assigned to three groups as control, diabetes group treated with 1 mL/kg/d saline (STZ + SP) and diabetes group treated with 600 mg/kg/d LEV (STZ + LEV). Following 4 weeks treatment, blood samples were collected for biochemical analysis and ovariectomy was performed for histopathological examination. Plasma anti-Mullerian hormone (AMH), glutathione and total anti-oxidant capacity values were significantly lower whereas lipid peroxides and transforming growth factor-β (TGF-β) values were significantly higher in STZ + SP group compared to control. LEV treatment successfully decreased lipid peroxidation and TGF-β levels, and also increased anti-oxidant parameters and AMH levels in diabetic rats. Saline-treated rats significantly displayed ovarian degeneration and decreased counts of follicles. However, treatment of diabetic rats with LEV effectively prevented the degenerative changes and follicle loss. Also, LEV suppressed ovarian nuclear factor-kappa B (NF-kB) immunoexpression in diabetic rats. Taken together, we propose that LEV can ameliorate the adverse effects of diabetes on ovarian function via decreasing NF-kB expression and oxidative stress and increasing anti-oxidant status in rats.

Neuroprotective effect of levetiracetam on hypoxic ischemic brain injury in neonatal rats

PURPOSE

Hypoxic-ischemic brain injury that occurs in the perinatal period is one of the leading causes of mental retardation, visual and auditory impairment, motor defects, epilepsy, cerebral palsy, and death in neonates. The severity of apoptosis that develops after ischemic hypoxia and reperfusion is an indication of brain injury. Thus, it may be possible to prevent or reduce injury with treatments that can be given before the reperfusion period following hypoxia and ischemia. Levetiracetam is a new-generation antiepileptic drug that has begun to be used in the treatment of epilepsy.

METHODS

The present study investigated the effects of levetiracetam on neuronal apoptosis with histopathological and biochemical tests in the early period and behavioral experiments in the late period.

RESULTS

This study showed histopathologically that levetiracetam reduces the number of apoptotic neurons and has a neuroprotective effect in a neonatal rat model of hypoxic-ischemic brain injury in the early period. On the other hand, we demonstrated that levetiracetam dose dependently improves behavioral performance in the late period.

CONCLUSIONS

Based on these results, we believe that one mechanism of levetiracetam's neuroprotective effects is due to increases in glutathione peroxidase and superoxide dismutase enzyme levels. To the best of our knowledge, this study is the first to show the neuroprotective effects of levetiracetam in a neonatal rat model of hypoxic-ischemic brain injury using histopathological, biochemical, and late-period behavioral experiments within the same experimental group.

The antiepileptic drug levetiracetam suppresses non-convulsive seizure activity and reduces ischemic brain damage in rats subjected to permanent middle cerebral artery occlusion

The antiepileptic drug Levetiracetam (Lev) has neuroprotective properties in experimental stroke, cerebral hemorrhage and neurotrauma. In these conditions, non-convulsive seizures (NCSs) propagate from the core of the focal lesion into perilesional tissue, enlarging the damaged area and promoting epileptogenesis. Here, we explore whether Lev neuroprotective effect is accompanied by changes in NCS generation or propagation. In particular, we performed continuous EEG recordings before and after the permanent occlusion of the middle cerebral artery (pMCAO) in rats that received Lev (100 mg/kg) or its vehicle immediately before surgery. Both in Lev-treated and in control rats, EEG activity was suppressed after pMCAO. In control but not in Lev-treated rats, EEG activity reappeared approximately 30-45 min after pMCAO. It initially consisted in single spikes and, then, evolved into spike-and-wave and polyspike-and-wave discharges. In Lev-treated rats, only rare spike events were observed and the EEG power was significantly smaller than in controls. Approximately 24 hours after pMCAO, EEG activity increased in Lev-treated rats because of the appearance of polyspike events whose power was, however, significantly smaller than in controls. In rats sacrificed 24 hours after pMCAO, the ischemic lesion was approximately 50% smaller in Lev-treated than in control rats. A similar neuroprotection was observed in rats sacrificed 72 hours after pMCAO. In conclusion, in rats subjected to pMCAO, a single Lev injection suppresses NCS occurrence for at least 24 hours. This electrophysiological effect could explain the long lasting reduction of ischemic brain damage caused by this drug.

Additional antiepileptic mechanisms of levetiracetam in lithium-pilocarpine treated rats

Several studies have addressed the antiepileptic mechanisms of levetiracetam (LEV); however, its effect on catecholamines and the inflammatory mediators that play a role in epilepsy remain elusive. In the current work, lithium (Li) pretreated animals were administered LEV (500 mg/kg i.p) 30 min before the induction of convulsions by pilocarpine (PIL). Li-PIL-induced seizures were accompanied by increased levels of hippocampal prostaglandin (PG) E2, myeloperoxidase (MPO), tumor necrosis factor-α, and interleukin-10. Moreover, it markedly elevated hippocampal lipid peroxides and nitric oxide levels, while it inhibited the glutathione content. Li-PIL also reduced hippocampal noradrenaline, as well as dopamine contents. Pretreatment with LEV protected against Li-PIL-induced seizures, where it suppressed the severity and delayed the onset of seizures in Li-PIL treated rats. Moreover, LEV reduced PGE2 and MPO, yet it did not affect the level of both cytokines in the hippocampus. LEV also normalized hippocampal noradrenaline, dopamine, glutathione, lipid peroxides, and nitric oxide contents. In conclusion, alongside its antioxidant property, LEV anticonvulsive effect involves catecholamines restoration, as well as inhibition of PGE2, MPO, and nitric oxide.

The beneficial effects of levetiracetam on polyneuropathy in the early stage of sepsis in rats: electrophysiological and biochemical evidence

ABSTRACT Critical illness polyneuropathy (CIP) is a common complication in long (≥1 week) critical/intensive care hospitalizations. Rapidly progressing atrophy and weakness of the limb, trunk and, particularly, respiratory muscles may lead to severe morbidity or mortality. The aim of the present study was to investigate the protective effects of levetiracetam (LEV) on CIP in the early stage of sepsis in rats. We simulated CIP by a surgically induced sepsis model and verified it by lower-limb electromyography (EMG) (amplitude and duration of CMAP, and distal latency). We evaluated the effects of various doses of LEV treatment (300, 600, and 1200 mg/kg i.p.) on CIP by performing electrophysiology, and determining plasma tumor necrosis factor (TNF)-α, lipid peroxides (malondialdehyde, MDA) levels, and total antioxidant capacity (TAC). Our data showed: (1) significant suppression of CMAP amplitude and prolongation of distal latency in the saline-treated sepsis group, and distal latency as well as CMAP amplitudes benefiting best from the 600 mg/kg LEV treatment; (2) significant rise in plasma TNF-α and MDA levels in the saline-treated sepsis group, but significant ameliorations by the 600 and 1200 mg/kg LEV treatment; (3) highly significant suppression of TAC in the saline-treated group, but profound reversals in all LEV-treated groups. We conclude that 300, 600, and 1200 mg/kg i.p. doses of post-septic treatment by LEV has possibly acted in a dose-dependent manner to both protect and restore the affected peripheral nerves' axon and myelin following surgical disturbance of the cecum to induce sepsis and consequent polyneuropathy.

Levetiracetam in brain ischemia: clinical implications in neuroprotection and prevention of post-stroke epilepsy

Several new antiepileptic drugs (AEDs) have been introduced for clinical use recently. These new AEDs, like the classic AEDs, target multiple cellular sites both pre- and postsynaptically. The use of AEDs as a possible neuroprotective strategy in brain ischemia is receiving increasing attention and the antiepileptic drug levetiracetam, a 2S-(2-oxo-1-pyrrolidiny1) butanamide, belonging to the pyrrolidone family, could have a crucial role in regulation of epileptogenesis and neuroprotection. Recent observations suggest that levetiracetam is both safe and effective against post-stroke seizures. In this review, the potential neuroprotective role in brain ischemia and the therapeutic implications of levetiracetam in post-stroke epilepsy are discussed.

Levetiracetam: safety and efficacy in neonatal seizures

PURPOSE

Neonatal seizures are common, especially in prematurity. Phenobarbital (PB) currently represents the antiepileptic drug (AED) of choice, despite being related to increased neuronal apoptosis in animal models and cognitive impairment in human subjects. Levetiracetam (LEV) may have a more favorable profile since it does not cause neuronal apoptosis in infant rodents.

METHODS

In a prospective feasibility study, LEV was applied as first-line treatment in 38 newborns with EEG-confirmed seizures, after ruling out hypoglycemia, hypocalcaemia, hypomagnesaemia and pyridoxin dependency. Initial intravenous doses of 10 mg/kg LEV were gradually increased to 30 mg/kg over 3 days with a further titration to 45-60 mg/kg at the end of the week. Acute intervention with up to 2 intravenous doses of PB 20 mg/kg was tolerated during LEV titration. LEV was switched to oral as soon as the infants' condition allowed. Based on clinical observation, EEG tracings (aEEG/routine EEGs), and lab data, drug safety and anticonvulsant efficacy were assessed over 12 months.

RESULTS

In 19 newborns a single PB dose of 20 mg/kg was administered, while 3 newborns received 2 PB doses. 30 infants were seizure free under LEV at the end of the first week and 27 remained seizure free at four weeks, while EEGs markedly improved in 24 patients at 4 weeks. In 19 cases, LEV was discontinued after 2-4 weeks, while 7 infants received LEV up to 3 months. No severe adverse effects were observed.

CONCLUSIONS

These results illustrate the safety of LEV treatment in neonatal seizures, including prematurity and suggest LEV anticonvulsant efficacy. Additional PB treatment admittedly constitutes a methodological shortcoming due to the prolonged anticonvulsive efficacy of PB. Double blind prospective controlled studies and long-term evaluation of cognitive outcome are called for.

Prospective, randomized, single-blinded comparative trial of intravenous levetiracetam versus phenytoin for seizure prophylaxis

BACKGROUND

Anti-epileptic drugs are commonly used for seizure prophylaxis after neurological injury. We performed a study comparing intravenous (IV) levetiracetam (LEV) to IV phenytoin (PHT) for seizure prophylaxis after neurological injury.

METHODS

In this prospective, single-center, randomized, single-blinded comparative trial of LEV versus PHT (2:1 ratio) in patients with severe traumatic brain injury (sTBI) or subarachnoid hemorrhage (NCT00618436) patients received IV load with either LEV or fosphenytoin followed by standard IV doses of LEV or PHT. Doses were adjusted to maintain therapeutic serum PHT concentrations or if patients had seizures. Continuous EEG (cEEG) monitoring was performed for the initial 72 h; outcome data were collected.

RESULTS

A total of 52 patients were randomized (LEV = 34; PHT = 18); 89% with sTBI. When controlling for baseline severity, LEV patients experienced better long-term outcomes than those on PHT; the Disability Rating Scale score was lower at 3 months (P = 0.042) and the Glasgow Outcomes Scale score was higher at 6 months (P = 0.039). There were no differences between groups in seizure occurrence during cEEG (LEV 5/34 vs. PHT 3/18; P = 1.0) or at 6 months (LEV 1/20 vs. PHT 0/14; P = 1.0), mortality (LEV 14/34 vs. PHT 4/18; P = 0.227). There were no differences in side effects between groups (all P > 0.15) except for a lower frequency of worsened neurological status (P = 0.024), and gastrointestinal problems (P = 0.043) in LEV-treated patients.

CONCLUSIONS

This study of LEV versus PHT for seizure prevention in the NSICU showed improved long-term outcomes of LEV-treated patients vis-à-vis PHT-treated patients. LEV appears to be an alternative to PHT for seizure prophylaxis in this setting.

Levetiracetam in the treatment of neonatal seizures: a pilot study

PURPOSE

At present, neonatal seizures are usually treated with Phenobarbital (PB) despite the limited efficacy and the potential risk this treatment holds for the developing brain. We report here a prospective pilot feasibility study on the use of Levetiracetam as monotherapy in the treatment of neonatal seizures.

METHODS

Six newborns (body weight>2000 g, gestational age>30 weeks) presenting with neonatal seizures were enrolled. Patients whose seizures were caused by electrolyte disturbances or hypoglycemia, or whose seizures did respond to pyridoxine were excluded. Patients previously treated with other antiepileptic drugs (AEDs), with the exception of single PB doses before and during titration, were excluded. LEV was administered orally, increasing the dose by 10mg/(kg day) over 3 days. Endpoint was the need of any additional AEDs (or PB) after day 3, or 3 months of LEV treatment. A decision regarding further treatment was made on an individual basis and follow-up was documented up to 8 months of age.

RESULTS

No severe adverse effects were observed. Mild sedation was reported in one infant. All six patients treated with oral LEV became seizure free within 6 days. Five patients remained seizure free after 3 months with ongoing LEV monotherapy. One infant developed pharmacoresistant epilepsy. Seizures relapsed later in the clinical course of two more patients, one of whom was no longer under LEV therapy.

DISCUSSION

Results from our small patient group indicate that LEV may be an alternative therapeutic option in neonatal seizures.

Effects of glucocorticoids on mood, memory, and the hippocampus. Treatment and preventive therapy

Corticosteroids, such as prednisone and dexamethasone, are commonly prescribed medications that suppress the immune system and decrease inflammation. Common side effects of long-term treatment with corticosteroids include weight gain, osteoporosis, and diabetes mellitus. This paper reviews the literature on psychiatric and cognitive changes during corticosteroid therapy and potential treatment options. Hypomania and mania are the most common mood changes during acute corticosteroid therapy, although depression has also been reported. However, depression is reported to be more common than mania during long-term treatment with corticosteroids. A decline in declarative and working memory is also reported during corticosteroid therapy. Corticosteroids are associated with changes in the temporal lobe, detected by structural, functional, and spectroscopic imaging. The mood and cognitive symptoms are dose dependent and frequently occur during the first few weeks of therapy. Other risk factors are not well characterized. Controlled trials suggest that lithium and phenytoin can prevent mood symptoms associated with corticosteroids. Lamotrigine and memantine also have been shown to reverse, at least partially, the declarative memory effects of corticosteroids. Uncontrolled trials suggest that antipsychotics, anti-seizure medications, and perhaps some antidepressants can also be useful for normalizing mood changes associated with corticosteroids. Thus, both the symptoms and treatment response are similar to those of bipolar disorder. Moreover, corticosteroid-induced mood and cognitive alterations have been shown to be reversible with dose reduction or discontinuation of treatment.

Levetiracetam for managing neurologic and psychiatric disorders

PURPOSE

The role of levetiracetam in different epileptic, nonepileptic, neurologic, and psychiatric disorders is discussed.

SUMMARY

Levetiracetam, an antiepileptic drug (AED), was first approved as an adjunctive therapy for the treatment of partial epilepsy in adults. It is currently being used in the treatment of multiple seizure disorders, including generalized tonic-clonic; absence; myoclonic, especially juvenile myoclonic; Lennox-Gastaut syndrome; and refractory epilepsy in children and adults. Data are emerging on possible uses of levetiracetam outside the realm of epilepsy because of its unique mechanisms of action. There is preliminary evidence about the efficacy of levetiracetam in the treatment of different psychiatric disorders, including anxiety, panic, stress, mood and bipolar, autism, and Tourette's syndrome. The most serious adverse effects associated with levetiracetam use are behavioral in nature and might be more common in patients with a history of psychiatric and neurobehavioral problems.

CONCLUSION

Levetiracetam is an effective AED with potential benefits in other neurologic and psychiatric disorders. The benefit-risk ratio in an individual patient with a specific condition should be used to determine its optimal use. Levetiracetam's use in nonepileptic conditions is not recommended until more data become available from larger trials.

Levetiracetam decreases the seizure activity and blood-brain barrier permeability in pentylenetetrazole-kindled rats with cortical dysplasia

This study investigates the effects of levetiracetam (LEV) on the functional and structural properties of blood-brain barrier (BBB) in pentylenetetrazole (PTZ)-kindled rats with cortical dysplasia (CD). Pregnant rats were exposed to 145 cGy of gamma-irradiation on embryonic day 17. In offsprings, kindling was induced by giving subconvulsive doses of PTZ three times per week for 45 days. While all kindled rats with CD died during epileptic seizures evoked by the administration of a convulsive dose of PTZ in 15 to 25 min, one week LEV (80 mg/kg) pretreatment decreased the mortality to 38% in the same setting. LEV caused a remarkable decrease (p<0.01) in extravasation of sodium fluorescein dye into the brain tissue of kindled animals with CD treated with convulsive dose of PTZ. Occludin immunoreactivity and expression remained essentially unchanged in all groups. Immunoreactivity for glial fibrillary acidic protein (GFAP) was observed to be slightly increased by acute convulsive challenge in kindled rats with CD while LEV pretreatment led to GFAP immunoreactivity comparable to that of controls. An increased c-fos immunoreactivity in kindled rats with CD exposed to convulsive PTZ challenge was also observed with LEV pretreatment. Tight junctions were ultrastructurally intact, whereas LEV decreased the increased pinocytotic activity in brain endothelium of kindled rats with CD treated with convulsive dose of PTZ. The present study showed that LEV decreased the increased BBB permeability considerably by diminishing vesicular transport in epileptic seizures induced by convulsive PTZ challenge in kindled animals with CD.

Mechanistic and pharmacologic aspects of status epilepticus and its treatment with new antiepileptic drugs

We review recent advances in our understanding and treatment of status epilepticus (SE). Repeated seizures cause an internalization of gamma-aminobutyric acid (GABA)(A) receptors, together with a movement of N-methyl-d-aspartate (NMDA) receptors to the synapse. As a result, the response of experimental SE to treatment with GABAergic drugs (but not with NMDA antagonists) fades with increasing seizure duration. Prehospital treatment, which acts before these changes are established, is finding increased acceptance, and solid evidence of its efficacy is available, particularly in children. Rational polypharmacy aims at multiple receptors or ion channels to increase inhibition and simultaneously reduce excitation. Combining GABA(A) agonists with NMDA antagonists and with agents acting at other sites is successful in treating experimental SE, and in reducing SE-induced brain damage and epileptogenesis. The relevance of these experimental data to clinical SE is actively debated. Valproate and levetiracetam have recently become available for intravenous use, and the use of ketamine and of other agents (topiramate, felbamate, etc.) have seen renewed interest. A rapidly increasing but largely anecdotal body of literature reports success in seizure control at the price of relatively few complications with the clinical use of those agents in refractory SE.

The role of interleukin-1 in seizures and epilepsy: a critical review

Interleukin-1 (IL-1) has a multitude of functions in the central nervous system. Some of them involve mechanisms that are related to epileptogenesis. The role of IL-1 in seizures and epilepsy has been investigated in both patients and animal models. This review aims to synthesize, based on the currently available literature, the consensus role of IL-1 in epilepsy. Three lines of evidence suggest a role for IL-1: brain tissue from epilepsy patients and brain tissue from animal models shows increased IL-1 expression after seizures, and IL-1 has proconvulsive properties when applied exogeneously. However, opposing results have been published as well. More research is needed to fully establish the role of IL-1 in seizure generation and epilepsy, and to explore possible new treatment strategies that are based on interference with intracellular signaling cascades that are initiated when IL-1 binds to its receptor.

Seizures, antiepileptics, antioxidants and oxidative stress: an insight for researchers

BACKGROUND

Neuronal hyperexcitability and excessive production of free radicals have been implicated in the pathogenesis of a considerable range of neurological disorders, including epilepsy. The high rate of oxidative metabolism, coupled with the low antioxidant defenses and the richness in polyunsaturated fatty acids, makes the brain highly vulnerable to free radical damage. The increased susceptibility of the brain to oxidative damage highlights the importance of understanding the role of oxidative stress in the pathophysiology of seizures.

OBJECTIVES

The present review aims not only to address the link between mitochondrial dysfunction, oxidative stress and seizures, but also the modulation of the pro-oxidant/antioxidant balance following seizures and treatment with antioxidants and antiepileptic drugs.

METHODS

A literature review revealed that there are articles that address the role of oxidative stress and mitochondrial dysfunction in neurological disorders, including those involving different seizure models where the modulation of the pro-oxidant/antioxidant balance by seizures per se and by antioxidant agents is discussed. However, the critical role of oxidative stress in all seizure models is not uniform. Therefore, there is a need for a review article that will address all these issues together.

RESULTS/CONCLUSIONS

The experimental and clinical data suggest a putative role of oxidative stress in the pathophysiology of certain seizure types. The pro-oxidant/antioxidant balance is not only modulated by seizures per se, but also by antiepileptic drugs. The ability of antioxidants for reducing the seizure manifestations and the accompanying biochemical changes (i.e., markers of oxidative stress) further supports a role of free radicals in seizures and highlights a possible role of antioxidants as adjuncts to antiepileptic drugs for better seizure control.

Neurodevelopmental impact of antiepileptic drugs and seizures in the immature brain

Seizure incidence during the neonatal period is higher than any other period in the lifespan, yet we know little about this period in terms of the effect of seizures or of the drugs used in their treatment. The fact that several antiepileptic drugs (AEDs) induce pronounced apoptotic neuronal death in specific regions of the immature brain prompts a search for AEDs that may be devoid of this action. Furthermore, there is a clear need to find out if a history of seizures alters the proapoptotic action of the AEDs. Our studies are aimed at both of these issues. Phenytoin, valproate, phenobarbital, and MK801 each induced substantial regionally specific cell death, whereas levetiracetam even in high doses (up to 1,500 mg/kg) did not have this action. In view of our previously findings of neuroprotective actions of repeated seizures in the adult brain, we also examined repeated seizures for a possible antiapoptotic action in the infant rat. Rat pups were preexposed to electroshock seizures (ECS) for 3 days (age 5-7 days) before receiving MK801 on day 7. The effect of ECS, which was consistently a 30% decrease in MK801-induced programmed cell death (PCD), suggests that repeated seizures can exert an antiapoptotic action in the infant brain. In contrast, PCD induced by valproate was not attenuated by ECS preexposure, suggesting that valproate-induced PCD is mechanistically distinct from that induced by MK801 and may not be activity-dependent. Presently, we do not know if this neuroprotective effect of seizures is deleterious or beneficial. If the seizures also enhance the survival of neurons that are destined to undergo naturally occurring PCD, early childhood seizures may have deleterious effects by preventing this necessary component of normal development. While this effect of seizures might be counteracted by AEDs, the fact that several AEDs shift the PCD to the other extreme, and trigger excessive neuronal cell loss, raises concern about whether the drug therapy may be more detrimental than the seizures. In this context, it is encouraging that we have identified at least one AED that is devoid of a proapoptotic action in the infant brain, even in high doses. It is now important to evaluate the long-term consequences of the changes in PCD in infancy by examining behavioral outcomes and seizure susceptibility in the AED- and seizure-exposed neonates when they reach adulthood.

Impact of levetiracetam on mood and cognition during prednisone therapy

PURPOSE

Corticosteroid excess is associated with impairment in declarative memory and hippocampal changes. In animals, phenytoin blocks the effects of stress on memory and hippocampal histology. Levetiracetam also shows neuroprotective properties in some animal models. This report examines whether levetiracetam prevents mood or cognitive changes secondary to prescription corticosteroids.

MATERIALS AND METHODS

Thirty outpatients given systemic corticosteroid therapy for asthma were randomized to either levetiracetam (1500 mg/day) or placebo given concurrently with the corticosteroids. Mood was assessed with the Hamilton rating scale for depression (HRSD), Young mania rating scale (YMRS) and activation (ACT) subscale of the internal state scale, declarative memory with the Rey auditory verbal learning test (RAVLT), and attention and executive functioning with the Stroop color and word test at baseline and after approximately 7 days of corticosteroid plus levetiracetam or placebo therapy.

RESULTS

Levetiracetam and placebo groups showed significant improvement from baseline to exit on RAVLT total words recalled with a non-significant change on other outcomes. No significant between-group differences were found. Initial prednisone dose showed a significant correlation with change in some cognitive domains.

CONCLUSIONS

Levetiracetam was well tolerated when combined with prednisone. Significant between-group differences in mood and cognition were not found.

Levetiracetam: the profile of a novel anticonvulsant drug-part I: preclinical data

The objective of this article was to review and summarize the available reports on the preclinical profile of the novel anticonvulsant drug levetiracetam (LEV). Therefore, a careful search was conducted in the MEDLINE database and combined with guidelines from regulatory agencies, proceedings of professional scientific meetings, and information provided by the manufacturers. This article provides detailed information on the anticonvulsant effects of LEV in various animal models of epilepsy and on its pharmacology in laboratory animals. The mechanism of action of LEV is reviewed, with special regard to its recently discovered binding site, the synaptic vesicle protein 2A. In general, LEV is shown to be a safe, broad-spectrum anticonvulsant drug with highly beneficial pharmacokinetic properties and a distinct mechanism of action. The clinical studies with LEV will be discussed in the second part of this review article to be published subsequently.

Effects of levetiracetam in lipid peroxidation level, nitrite-nitrate formation and antioxidant enzymatic activity in mice brain after pilocarpine-induced seizures

: Oxidative stress has been implicated in a large number of human degenerative diseases, including epilepsy. Levetiracetam (LEV) is a new antiepileptic agent with broad-spectrum effects on seizures and animal models of epilepsy. Recently, it was demonstrated that the mechanism of LEV differs from that of conventional antiepileptic drugs. Objectifying to investigate if LEV mechanism of action involves antioxidant properties, lipid peroxidation levels, nitrite-nitrate formation, catalase activity, and glutathione (GSH) content were measured in adult mice brain. The neurochemical analyses were carried out in hippocampus of animals pretreated with LEV (200 mg/kg, i.p.) 60 min before pilocarpine-induced seizures (400 mg/kg, s.c.). The administration of alone pilocarpine, 400 mg/kg, s.c. (P400) produced a significant increase of lipid peroxidation level in hippocampus. LEV pretreatment was able to counteract this increase, preserving the lipid peroxidation level in normal value. P400 administration also produced increase in the nitrite-nitrate formation and catalase activity in hippocampus, beyond a decrease in GSH levels. LEV administration before P400 prevented the P400-induced alteration in nitrite-nitrate levels and preserved normal values of catalase activity in hippocampus. Moreover, LEV administration prevented the P400-induced loss of GSH in this cerebral area. The present data suggest that the protective effects of LEV against pilocarpine-induced seizures can be mediated, at least in part, by reduction of lipid peroxidation and hippocampal oxidative stress.