The Interconnected Mechanisms of Oxidative Stress and Neuroinflammation in Epilepsy

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

Self-compassion and depression, anxiety, and resilience in adults with epilepsy

BACKGROUND

Research suggests that people with epilepsy (PWE) are more likely to experience depression and anxiety than the general population. Given the adversity associated with the condition, resilience may also be important. However, to date, resilience has been largely overlooked in the epilepsy literature. Self-compassion has been widely associated with improved psychological wellbeing and, to a lesser extent, resilience. However, the relationship between self-compassion and depression, anxiety, and resilience in PWE has not been examined.

OBJECTIVES

Using a quantitative cross-sectional survey design, the aim of the present study was to examine the extent to which self-compassion predicted depression, anxiety, and resilience when controlling for demographic and illness-related variables.

METHODS

Adults with epilepsy were invited to take part in a survey online or in epilepsy or neurology clinics. Two-hundred and seventy participants completed the survey, and data were analyzed using hierarchical multiple regression models.

RESULTS

In this sample of PWE, self-compassion significantly predicted lower depression and anxiety and higher resilience when other significant sociodemographic and illness-related variables had been taken into account.

CONCLUSIONS

The findings of the present study indicate that self-compassion could be an important factor in determining psychological outcomes for adults with epilepsy, and its role is worthy of further exploration to help improve psychological outcomes for PWE.

Pharmacokinetic drug evaluation of lacosamide for the treatment of partial-onset seizures

The goal of pharmacologic therapy with antiepileptic drugs (AEDs) is to reduce the frequency of seizures and achieve a seizure-free state with minimal side effects. However 30% of patients treated with available AEDs continue to experience uncontrolled seizures. There is still need for new AEDs with enhanced effectiveness and tolerability. Areas covered: The present manuscript is based on an extensive Internet and PubMed search from 1992 to 2017. It is focused on the pharmacokinetic properties of lacosamide (LCM) for the treatment of partial-onset seizures. Expert opinion: LCM is an anticonvulsant approved as add-on treatment or monotherapy of partial-onset seizures with or without secondary generalization. LCM shares many of the pharmacokinetic characteristics of an ideal AED. LCM displays linear and dose-proportional pharmacokinetics, rapid and complete absorption from the gastrointestinal tract, low plasma-protein binding, renal excretion and a terminal half-life that supports twice-daily dosing. Because the bioavailability and tolerability of oral and intravenous LCM are comparable, LCM offers the advantage of direct conversion from oral to intravenous administration, and vice versa, without the need for titration or dose adjustment. Further studies are needed to determine optimal timing, dosing, as well as the safety and efficacy of LCM in status epilepticus.

Efficacy and Safety of Levetiracetam and Carbamazepine as Monotherapy in Partial Seizures

Introduction. Levetiracetam (LEV) is a newer antiepileptic drug with better pharmacokinetic profile. Currently, it is frequently used for the treatment of partial seizures. The present study was undertaken to compare the efficacy and safety of LEV and Carbamazepine (CBZ) in partial epilepsy. Methods. This was a prospective, open labeled, randomized study. It was conducted in participants suffering from partial seizures after the approval of ethics committee and written informed consent. The first group received Tab LEV (500 to 3000 mg/day) and the second group received Tab CBZ (300 to 600 mg/day). The primary outcomes were efficacy and safety. The secondary outcome was the Quality of Life (QOL). Efficacy was assessed by comparing the seizure freedom rates at the end of 6 months. Safety profile was evaluated by comparing the adverse effects. QOL was assessed by QOLIE-10 scale. Results. The overall seizure freedom rate at the end of 6 months was 71.42% in CBZ group compared to 78.57% in LEV group (p = 0.2529). Both LEV and CBZ reported a similar incidence of adverse reactions. LEV group reported more behavioral changes like increased aggression and anxiety. Also, it showed better QOL compared to the CBZ group. Conclusion. LEV monotherapy and CBZ monotherapy demonstrated similar efficacy for treatment of partial epilepsy and were found to be well tolerated.

Zonisamide: a review of its use as adjunctive therapy in the management of partial seizures in pediatric patients aged ≥6 years

Oral zonisamide (Zonegran®) is a benzisoxazole derivative chemically unrelated to other antiepileptic drugs (AEDs). It is approved in the EU as an adjunct to other AEDs in the treatment of pediatric patients aged ≥6 years with partial seizures, with or without secondary generalization. In a randomized, double-blind, multinational, phase III study in pediatric patients aged 6-17 years with partial seizures, the proportion of patients achieving a ≥50 % reduction from baseline in seizure frequency per 28 days during the maintenance treatment period was significantly higher with adjunctive therapy with zonisamide than placebo. The antiepileptic efficacy of zonisamide was sustained during a 59-week extension study in this patient population. Zonisamide was generally well tolerated in these studies, with the majority of adverse events being mild or moderate in severity. Thus, oral zonisamide as an adjunctive therapy to other AEDs provides a useful option in the treatment of pediatric patients aged ≥6 years with partial seizures.

Lacosamide: a review of its use as adjunctive therapy in the management of partial-onset seizures

Lacosamide (Vimpat(®)) is a functionalized amino acid available orally (as a syrup or tablet) and as an intravenous infusion. It is believed to exert its antiepileptic effect by selectively enhancing the slow inactivation of voltage-gated sodium channels. Lacosamide is approved in several countries worldwide as an adjunctive therapy for the treatment of partial-onset seizures; however, prescribing regulations differ between countries. This article reviews the use of lacosamide as indicated in adults and adolescents (aged 16-18 years) in the EU, where it is approved in this patient population as an adjunctive therapy to other AEDs in the treatment of partial-onset seizures, with or without secondary generalization. In three randomized, double-blind, placebo-controlled, multicentre studies in adults and adolescents (aged 16-18 years) with partial-onset seizures, adjunctive therapy with oral lacosamide (administered for an initial titration period followed by 12 weeks' maintenance therapy) generally reduced the frequency of seizures to a significantly greater extent than placebo, with antiepileptic efficacy sustained following longer-term treatment (up to 8 years) in this patient population. Oral and intravenous lacosamide were generally well tolerated in clinical studies, with the majority of adverse events being mild or moderate in severity. Very common adverse reactions following adjunctive therapy with oral lacosamide included diplopia, dizziness, headache and nausea; the tolerability profile of intravenous lacosamide appeared consistent with that of oral lacosamide, although intravenous administration was associated with local adverse events, such as injection site discomfort or pain, irritation and erythema. Thus, oral and intravenous lacosamide as an adjunctive therapy to other AEDs provides a useful option in the treatment of patients with partial-onset seizures.

Levetiracetam: a review of its use in epilepsy

Levetiracetam (Keppra®, E Keppra®) is an established second-generation antiepileptic drug (AED). Worldwide, levetiracetam is most commonly approved as adjunctive treatment of partial onset seizures with or without secondary generalization; other approved indications include monotherapy treatment of partial onset seizures with or without secondary generalization, and adjunctive treatment of myoclonic seizures associated with juvenile myoclonic epilepsy and primary generalized tonic-clonic (GTC) seizures associated with idiopathic generalized epilepsy. Levetiracetam has a novel structure and unique mechanisms of action. Unlike other AEDs, the mechanisms of action of levetiracetam appear to involve neuronal binding to synaptic vesicle protein 2A, inhibiting calcium release from intraneuronal stores, opposing the activity of negative modulators of GABA- and glycin-gated currents and inhibiting excessive synchronized activity between neurons. In addition, levetiracetam inhibits N-type calcium channels. Levetiracetam is associated with rapid and complete absorption, high oral bioavailability, minimal metabolism that consists of hydrolysis of the acetamide group, and primarily renal elimination. It lacks cytochrome P450 isoenzyme-inducing potential and is not associated with clinically significant pharmacokinetic interactions with other drugs, including other AEDs. The efficacy of oral immediate-release levetiracetam in controlling seizures has been established in numerous randomized, double-blind, controlled, multicentre trials in patients with epilepsy. Adjunctive levetiracetam reduced the frequency of seizures in paediatric and adult patients with refractory partial onset seizures to a significantly greater extent than placebo. Monotherapy with levetiracetam was noninferior to that with carbamazepine controlled release in controlling seizures in patients with newly diagnosed partial onset seizures. Levetiracetam also provided seizure control relative to placebo as adjunctive therapy in patients with idiopathic generalized epilepsy with myoclonic seizures or GTC seizures. In addition, patients receiving oral levetiracetam showed improvements in measures of health-related quality of life relative to those receiving placebo. Although treatment-emergent adverse events were commonly reported in the clinical trials of levetiracetam, the overall proportion of patients who experienced at least one treatment-emergent adverse event was broadly similar in the levetiracetam and placebo treatment groups, with most events being mild to moderate in severity. Levetiracetam is not associated with cognitive impairment or drug-induced weight gain, but has been associated with behavioural adverse effects in some patients.