Personalized medicine approaches in epilepsy

Potential merits and flaws of large language models in epilepsy care: A critical review

The current pace of development and applications of large language models (LLMs) is unprecedented and will impact future medical care significantly. In this critical review, we provide the background to better understand these novel artificial intelligence (AI) models and how LLMs can be of future use in the daily care of people with epilepsy. Considering the importance of clinical history taking in diagnosing and monitoring epilepsy-combined with the established use of electronic health records-a great potential exists to integrate LLMs in epilepsy care. We present the current available LLM studies in epilepsy. Furthermore, we highlight and compare the most commonly used LLMs and elaborate on how these models can be applied in epilepsy. We further discuss important drawbacks and risks of LLMs, and we provide recommendations for overcoming these limitations.

X-linked neuronal migration disorders: Gender differences and insights for genetic screening

Cortical development depends on neuronal migration of both excitatory and inhibitory interneurons. Neuronal migration disorders (NMDs) are conditions characterised by anatomical cortical defects leading to varying degrees of neurocognitive impairment, developmental delay and seizures. Refractory epilepsy affects 15 million people worldwide, and it is thought that cortical developmental disorders are responsible for 25% of childhood cases. However, little is known about the epidemiology of these disorders, nor are their aetiologies fully understood, though many are associated with sporadic genetic mutations. In this review, we aim to highlight X-linked NMDs including lissencephaly, periventricular nodular heterotopia and polymicrogyria because of their mostly familial inheritance pattern. We focus on the most prominent genes responsible: including DCX, ARX, FLNA, FMR1, L1CAM, SRPX2, DDX3X, NSHDL, CUL4B and OFD1, outlining what is known about their prevalence among NMDs, and the underlying pathophysiology. X-linked disorders are important to recognise clinically, as females often have milder phenotypes. Consequently, there is a greater chance they survive to reproductive age and risk passing the mutations down. Effective genetic screening is important to prevent and treat these conditions, and for this, we need to know gene mutations and have a clear understanding of the function of the genes involved. This review summarises the knowledge base and provides clear direction for future work by both scientists and clinicians alike.

Tetramethylpyrazine contributes to the neuroprotection in a rodent epileptic model of pentylenetetrazole-induced kindling

OBJECTIVES

In this study, tetramethylpyrazine (TMP) was evaluated for its therapeutic potential as an alternative therapy for epileptogenesis and its associated comorbidities in rats.

METHODS

The sub-convulsant dose of pentylenetetrazole (PTZ) (35 mg/kg, intraperitoneally) was injected on alternative days to produce kindling for 32 days and observed for seizure score percent of kindled animals in each group. After kindling, the animals were evaluated in models of anxiety, memory and predictive of depression. The neuroprotective effect of TMP was assessed by estimating the biochemical parameters in the cortex and hippocampus of the brain. Histopathological alterations were also observed in the cortex and hippocampus (CA1, CA3 and DG).

KEY FINDINGS

The administration of TMP reduced the seizure score and percentage of kindled animals dose-dependently. Furthermore, TMP significantly improved the behavioural parameters measured in the predictive models of depression but not in the anxiety and cognitive performances of the animals. The oxidative-nitrosative stress, excitotoxicity, neuroinflammation and histological alterations in the brain induced by PTZ were significantly mitigated by administering the TMP high dose of 60 mg/kg.

CONCLUSION

In conclusion, the TMP attenuated the depression behaviour in the PTZ-induced kindled rats, and reduced the oxidative-nitrosative stress, excitotoxicity, neuroinflammation and histological alterations of the brain.

Novel Near-Infrared Fluorescence Probe for Bioimaging and Evaluating Superoxide Anion Fluctuations in Ferroptosis-Mediated Epilepsy

Ferroptosis is an iron-regulated, caspase-mediated pathway of cell death that is associated with the excessive aggregation of lipid-reactive oxygen species and is extensively involved in the evolution of many diseases, including epilepsy. The superoxide anion (O2•-), as the primary precursor of ROS, is closely related to ferroptosis-mediated epilepsy. Therefore, it is crucial to establish a highly effective and convenient method for the real-time dynamic monitoring of O2•- during the ferroptosis process in epilepsy for the diagnosis and therapy of ferroptosis-mediated epilepsy. Nevertheless, no probes for detecting O2•- in ferroptosis-mediated epilepsy have been reported. Herein, we systematically conceptualized and developed a novel near-infrared (NIR) fluorescence probe, NIR-FP, for accurately tracking the fluctuation of O2•- in ferroptosis-mediated epilepsy. The probe showed exceptional sensitivity and outstanding selectivity toward O2•-. In addition, the probe has been utilized effectively to bioimage and evaluate endogenous O2•- variations in three types of ferroptosis-mediated epilepsy models (the kainic acid-induced chronic epilepsy model, the pentylenetetrazole-induced acute epilepsy model, and the pilocarpine-induced status epilepticus model). The above applications illustrated that NIR-FP could serve as a reliable and suitable tool for guiding the accurate diagnosis and therapy of ferroptosis-mediated epilepsy.

Fighting Epilepsy with Nanomedicines-Is This the Right Weapon?

Epilepsy is a chronic and complex condition and is one of the most common neurological diseases, affecting about 50 million people worldwide. Pharmacological therapy has been, and is likely to remain, the main treatment approach for this disease. Although a large number of new antiseizure drugs (ASDs) has been introduced into the market in the last few years, many patients suffer from uncontrolled seizures, demanding the development of more effective therapies. Nanomedicines have emerged as a promising approach to deliver drugs to the brain, potentiating their therapeutic index. Moreover, nanomedicine has applied the knowledge of nanoscience, not only in disease treatment but also in prevention and diagnosis. In the current review, the general features and therapeutic management of epilepsy will be addressed, as well as the main barriers to overcome to obtain better antiseizure therapies. Furthermore, the role of nanomedicines as a valuable tool to selectively deliver drugs will be discussed, considering the ability of nanocarriers to deal with the less favourable physical-chemical properties of some ASDs, enhance their brain penetration, reduce the adverse effects, and circumvent the concerning drug resistance.

Cytogenomic epileptology

Molecular cytogenetic and cytogenomic studies have made a contribution to genetics of epilepsy. However, current genomic research of this devastative condition is generally focused on the molecular genetic aspects (i.e. gene hunting, detecting mutations in known epilepsy-associated genes, searching monogenic causes of epilepsy). Nonetheless, chromosomal abnormalities and copy number variants (CNVs) represent an important part of genetic defects causing epilepsy. Moreover, somatic chromosomal mosaicism and genome/chromosome instability seem to be a possible mechanism for a wide spectrum of epileptic conditions. This idea becomes even more attracting taking into account the potential of molecular neurocytogenetic (neurocytogenomic) studies of the epileptic brain. Unfortunately, analyses of chromosome numbers and structure in the affected brain or epileptogenic brain foci are rarely performed. Therefore, one may conclude that cytogenomic area of genomic epileptology is poorly researched. Accordingly, molecular cytogenetic and cytogenomic studies of the clinical cohorts and molecular neurocytogenetic analyses of the epileptic brain appear to be required. Here, we have performed a theoretical analysis to define the targets of the aforementioned studies and to highlight future directions for molecular cytogenetic and cytogenomic research of epileptic disorders in the widest sense. To succeed, we have formed a consortium, which is planned to perform at least a part of suggested research. Taking into account the nature of the communication, "cytogenomic epileptology" has been introduced to cover the research efforts in this field of medical genomics and epileptology. Additionally, initial results of studying cytogenomic variations in the Russian neurodevelopmental cohort are reviewed with special attention to epilepsy. In total, we have concluded that (i) epilepsy-associated cytogenomic variations require more profound research; (ii) ontological analyses of epilepsy genes affected by chromosomal rearrangements and/or CNVs with unraveling pathways implicating epilepsy-associated genes are beneficial for epileptology; (iii) molecular neurocytogenetic (neurocytogenomic) analysis of postoperative samples are warranted in patients suffering from epileptic disorders.

New Trends and Most Promising Therapeutic Strategies for Epilepsy Treatment

Background: Despite the wide availability of novel anti-seizure medications (ASMs), 30% of patients with epilepsy retain persistent seizures with a significant burden in comorbidity and an increased risk of premature death. This review aims to discuss the therapeutic strategies, both pharmacological and non-, which are currently in the pipeline.

Methods: PubMed, Scopus, and EMBASE databases were screened for experimental and clinical studies, meta-analysis, and structured reviews published between January 2018 and September 2021. The terms “epilepsy,” “treatment” or “therapy,” and “novel” were used to filter the results.

Conclusions: The common feature linking all the novel therapeutic approaches is the spasmodic rush toward precision medicine, aiming at holistically evaluating patients, and treating them accordingly as a whole. Toward this goal, different forms of intervention may be embraced, starting from the choice of the most suitable drug according to the type of epilepsy of an individual or expected adverse effects, to the outstanding field of gene therapy. Moreover, innovative insights come from in-vitro and in-vivo studies on the role of inflammation and stem cells in the brain. Further studies on both efficacy and safety are needed, with the challenge to mature evidence into reliable assets, ameliorating the symptoms of patients, and answering the challenges of this disease.

Epilepsy Syndromes: Current Classifications and Future Directions

This review describes the clinical presentations and treatment options for commonly recognized epilepsy syndromes in the pediatric age group, based on the 2017 International League Against Epilepsy classification. Structural epilepsies that are amenable to surgical intervention are discussed. Lastly, emerging technologies are reviewed that are expanding our knowledge of underlying epilepsy pathologies and will guide future syndromic classification systems including genetic testing and tissue repositories.

Induced Pluripotent Stem Cell-Based Systems for Personalising Epilepsy Treatment: Research Ethics Challenges and New Insights for the Ethics of Personalised Medicine

ABSTRACTThis paper examines potential ethical and legal issues arising during the research, development and clinical use of a proposed strategy in personalized medicine (PM): using human induced pluripotent stem cell (iPSC)-derived tissue cultures as predictive models of individual patients to inform treatment decisions. We focus on epilepsy treatment as a likely early application of this strategy, for which early-stage stage research is underway. In relation to the research process, we examine issues associated with biological samples; data; health; vulnerable populations; neural organoids; and what level of accuracy justifies using the iPSC-derived neural tissue system. In relation to clinical use, we examine potential uses in pre-natal screening, and effects on clinical decision-making. Although our focus is providing recommendations for researchers developing work in this area, we identify the novel issue of deciding on an acceptable accuracy level for the system. We also emphasize an issue thus far neglected in the ethics of PM: PM tends to represent treatment decisions as though they should be directed solely by biomedical information, but this in itself could be detrimental to best personalizing treatment decisions in the clinic.

Potential for improved retention rate by personalized antiseizure medication selection: A register-based analysis

OBJECTIVE

The first antiseizure medication (ASM) is ineffective or intolerable in 50% of epilepsy cases. Selection between more than 25 available ASMs is guided by epilepsy factors, but also age and comorbidities. Randomized evidence for particular patient subgroups is seldom available. We asked whether register data could be used for retention rate calculations based on demographics, comorbidities, and ASM history, and quantified the potential improvement in retention rates of the first ASM in several large epilepsy cohorts. We also describe retention rates in patients with epilepsy after traumatic brain injury and dementia, patient groups with little available evidence.

METHODS

We used medical, demographic, and drug prescription data from epilepsy cohorts from comprehensive Swedish registers, containing 6380 observations. By analyzing 381 840 prescriptions, we studied retention rates of first- and second-line ASMs for patients with epilepsy in multiple sclerosis (MS), brain infection, dementia, traumatic brain injury, or stroke. The rank of retention rates of ASMs was validated by comparison to published randomized control trials. We identified the optimal stratification for each brain disease, and quantified the potential improvement if all patients had received the optimal ASM.

RESULTS

Using optimal stratification for each brain disease, the potential improvement in retention rate (percentage points) was MS, 20%; brain infection, 21%; dementia, 14%; trauma, 21%; and stroke, 14%. In epilepsy after trauma, levetiracetam had the highest retention rate at 80% (95% confidence interval [CI] = 65-89), exceeding that of the most commonly prescribed ASM, carbamazepine (p = .04). In epilepsy after dementia, lamotrigine (77%, 95% CI = 68-84) and levetiracetam (74%, 95% CI = 68-79) had higher retention rates than carbamazepine (p = .006 and p = .01, respectively).

SIGNIFICANCE

We conclude that personalized ASM selection could improve retention rates and that national registers have potential as big data sources for personalized medicine in epilepsy.

A hydrogen sulfide donor suppresses pentylenetetrazol-induced seizures in rats via PKC signaling

Epilepsy is a serious neurological disorder. Available antiepileptic drugs are still lacking. Hydrogen sulfide (H2S), a neuron-protective endogenous gasotransmitter, is reported to have effect on epilepsy. But it remains to be determined for its mechanism. In the present study, we found that a novel carbazole-based H2S donor could effectively suppress pentylenetetrazol-induced seizures in rats. The H2S donor could alleviate not only the epileptic behavior of animals but also the hippocampal EEG activity of seizures. The H2S donor down-regulated the expression of aquaporin 4 in the hippocampus of epilepsy rats. The H2S donor also decreased the seizure-induced release of inflammatory cytokines including IL-1β, IL-6 and TNF-α. In addition, the H2S donor increased protein kinase C (PKC) expression in the hippocampus of epilepsy rats. These effects of the H2S donor on epilepsy rats were attenuated after blockade of PKC signaling by Go6983, suggesting that PKC signaling participated in the antiepileptic process of H2S donor. Taken together, the H2S donor has a beneficial effect on epilepsy control in a PKC-dependent manner.

WITHDRAWN: Evaluation of the factors that may contribute to the responsiveness of anti-epileptic treatments in pediatric patients, a study from Jordan

This article has been withdrawn at the request of the editor and publisher. The publisher regrets that an error occurred which led to the publication of this paper, which had been rejected by the editor. This error bears no reflection on the editor. The publisher apologizes to the authors, editor and the readers for this unfortunate error. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

The Concept of an Epilepsy Brain Bank

Epilepsy comprises more than 40 clinical syndromes affecting millions of patients and families worldwide. To decode the molecular and pathological framework of epilepsy researchers, need reliable human epilepsy and control brain samples. Brain bank organizations collecting and supplying well-documented clinically and pathophysiologically tissue specimens are important for high-quality neurophysiology and neuropharmacology studies for epilepsy and other neurological diseases. New development in molecular mechanism and new treatment methods for neurological disorders have evoked increased demands for human brain tissue. An epilepsy brain bank is a storage source for both the frozen samples as well as the formaldehyde fixed paraffin embedded (FFPE) tissue from epilepsy surgery resections. In 2014, the University of Saskatchewan have started collecting human epilepsy brain tissues for the first time in Canada. This review highlights the necessity and importance of Epilepsy Brain bank that provides unique access for research to valuable source of brain tissue and blood samples from epilepsy patients.

Novel therapies for epilepsy in the pipeline

Despite the availability of many antiepileptic drugs (AEDs) (old and newly developed) and, as recently suggested, their optimization in the treatment of patients with uncontrolled seizures, more than 30% of patients with epilepsy continue to experience seizures and have drug-resistant epilepsy; the management of these patients represents a real challenge for epileptologists and researchers. Resective surgery with the best rates of seizure control is not an option for all of them; therefore, research and discovery of new methods of treating resistant epilepsy are of extreme importance. In this article, we will discuss some innovative approaches, such as P-glycoprotein (P-gp) inhibitors, gene therapy, stem cell therapy, traditional and novel antiepileptic devices, precision medicine, as well as therapeutic advances in epileptic encephalopathy in children; these treatment modalities open up new horizons for the treatment of patients with drug-resistant epilepsy.

Sex-Dependent Signaling Pathways Underlying Seizure Susceptibility and the Role of Chloride Cotransporters

Seizure incidence, severity, and antiseizure medication (ASM) efficacy varies between males and females. Differences in sex-dependent signaling pathways that determine network excitability may be responsible. The identification and validation of sex-dependent molecular mechanisms that influence seizure susceptibility is an emerging focus of neuroscience research. The electroneutral cation-chloride cotransporters (CCCs) of the SLC12A gene family utilize Na⁺-K⁺-ATPase generated electrochemical gradients to transport chloride into or out of neurons. CCCs regulate neuronal chloride gradients, cell volume, and have a strong influence over the electrical response to the inhibitory neurotransmitter GABA. Acquired or genetic causes of CCCs dysfunction have been linked to seizures during early postnatal development, epileptogenesis, and refractoriness to ASMs. A growing number of studies suggest that the developmental expression of CCCs, such as KCC2, is sex-dependent. This review will summarize the reports of sexual dimorphism in epileptology while focusing on the role of chloride cotransporters and their associated modulators that can influence seizure susceptibility.

Microporous polymer based on the new compound "bi-(4-vinyl phenylquinoline) amide" for enrichment and quantitative determination of lamotrigine in rat and human serum

Lamotrigine is one of the most widely used antiepileptic drugs in the treatment of epilepsy. This kind of drug needs to be used in the long term and should be quantitatively detected in the blood of patients to avoid drug toxicity caused by individual differences and environmental and pathological changes in the process of taking. The detection of antiepileptic drugs in human blood is challenging because of their low contents and the interference of complex matrices. Thus, the sample enrichment method has been commonly used to improve the sensitivity of detection. In this work, we have synthesized a new "bi-(4-vinyl phenylquinoline) amide" compound and used it as the monomer to produce the hyper-cross-linked microporous polymer for the enrichment of lamotrigine. This material has a high adsorption capacity, specificity, and linearity, which can improve the detection sensitivity of lamotrigine by high-performance liquid chromatography (HPLC). The mechanism of this phenomenon has also been investigated. Finally, we have developed the microporous polymer enrichment coupled with HPLC method for the quantitative determination of lamotrigine in rat and human serum samples. This method has excellent precision, accuracy, and recovery, meeting the test of biological sample. The low limit of quantitation was 0.625 μg/mL. Graphical abstract.

Adverse drug reactions associated with six commonly used antiepileptic drugs in southern China from 2003 to 2015

BACKGROUND

This active, open observational study aimed to investigate adverse drug reactions (ADRs) associated with six commonly used antiepileptic drugs (AEDs) in southern Chinese outpatients with epilepsy from 2003 to 2015.

METHODS

The Wenzhou Epilepsy Follow-Up Registry Database (WEFURD) was established by a single epilepsy center in China in January 2003 to record AED efficacy and the associated ADRs by registered outpatients diagnosed with epilepsy. We reviewed the data of outpatients who had only taken one or more of six commonly used AEDs, namely, carbamazepine (CBZ), valproate (VPA), lamotrigine (LTG), oxcarbazepine (OXC), topiramate (TPM) and levetiracetam (LEV), and were registered in the WEFURD between 2003 and 2015. We evaluated the ADRs caused by the single or combined use of the above six specific AEDs based on the WHO-UMC scale. The data of the ADRs were categorized by age, sex, number of AEDs related to ADRs, medications, seriousness of ADRs, causality levels of the WHO-UMC scale and system organ class (SOC). The unit of analysis was one ADR.

RESULTS

A total of 3069 epilepsy outpatients (1807 outpatients with 5049 eligible ADRs and 1262 outpatients without ADRs) were included. The overall ADR rate was 58.88% (1807/3069). An average of 2.79 ADRs (5049/1807) occurred per patient with an ADR; 53.8% of the 5049 ADRs were recorded in females, and 50.4% were caused by monotherapy. Of the ADRs, 10.6% (537/5049) were severe adverse reactions (SARs), including 34 serious adverse effects (SAEs). The SAR rates caused by one, two and three or more AEDs were 9.9, 10.0 and 19.6%, respectively (p <  0.001). Eighteen SOC categories were identified, and the top three were psychiatric disorders (1633/5049, 32.3%), neurological disorders (1222/5049, 24.2%) and gastrointestinal disorders (564/5049, 11.2%). Of the 537 SARs, skin and appendage disorders accounted for 24.4% (131/537). Among the 34 SAEs, serious allergies, fetal malformations, renal calculus and pancreatitis accounted for the majority.

CONCLUSIONS

Our findings suggest that clinicians should pay attention to psychiatric ADRs and be alert for SARs, especially when three or more AEDs are used together. Moreover, active surveillance might provide another method of pharmacovigilance in China.

Molecular mechanisms of neuroprotective effect of adjuvant therapy with phenytoin in pentylenetetrazole-induced seizures: Impact on Sirt1/NRF2 signaling pathways

Current anticonvulsant therapies are principally aimed at suppressing neuronal hyperexcitability to prevent or control the incidence of seizures. However, the role of oxidative stress processes in seizures led to the proposition that antioxidant compounds may be considered as promising candidates for limiting the progression of epilepsy. Accordingly, the aim of this study is to determine if coenzyme Q10 (CoQ10) and alpha-tocopherol (α-Toc) have a neuroprotective effect in rats against the observed oxidative stress and inflammation during seizures induced by pentylenetetrazole (PTZ) in rats, and to study their interactions with the conventional antiseizure drug phenytoin (PHT), either alone or in combination. Overall, the data revealed that α-Toc and CoQ10 supplementation can ameliorate PTZ-induced seizures and recommended that nuclear factor erythroid 2-related factor 2 (NRF2) and silencing information regulator 1 (Sirt1) signaling pathways may exemplify strategic molecular targets for seizure therapies. The results of the present study provide novel mechanistic insights regarding the protective effects of antioxidants and suggest an efficient therapeutic strategy to attenuate seizures. Additionally, concurrent supplementation of CoQ10 and α-Toc may be more effective than either antioxidant alone in decreasing inflammation and oxidative stress in both cortical and hippocampal tissues. Also, CoQ10 and α-Toc effectively reverse the PHT-mediated alterations in the brain antioxidant status when compared to PHT only.

Personalized Dietary Management of Overweight and Obesity Based on Measures of Insulin and Glucose

During the past several decades, numerous trials have compared various diets for the management of overweight and obesity, assuming that a single dietary strategy would be appropriate for all individuals. These studies have failed to provide strong evidence for the efficacy of any particular diet, and it is likely that different people will have different levels of success on different diets. We identified studies investigating pretreatment glycemia or insulinemia status, or both, of the individual as prognostic markers of weight loss during periods in which the composition of a participant's diet was known. Overall, research suggests that providing specific diets for weight management based on pretreatment glycemia and insulinemia statuses holds great promise for advancing personalized nutrition.

Individualizing Treatment Approaches for Epileptic Patients with Glucose Transporter Type1 (GLUT-1) Deficiency

Monogenic and polygenic mutations are important contributors in patients suffering from epilepsy, including metabolic epilepsies which are inborn errors of metabolism with a good respond to specific dietetic treatments. Heterozygous variation in solute carrier family 2, facilitated glucose transporter member 1 (SLC2A1) and mutations of the GLUT1/SLC2A2 gene results in the failure of glucose transport, which is related with a glucose type-1 transporter (GLUT1) deficiency syndrome (GLUT1DS). GLUT1 deficiency syndrome is a treatable disorder of glucose transport into the brain caused by a variety of mutations in the SLC2A1 gene which are the cause of different neurological disorders also with different types of epilepsy and related clinical phenotypes. Since patients continue to experience seizures due to a pharmacoresistance, an early clinical diagnosis associated with specific genetic testing in SLC2A1 pathogenic variants in clinical phenotypes could predict pure drug response and might improve safety and efficacy of treatment with the initiation of an alternative energy source including ketogenic or analog diets in such patients providing individualized strategy approaches.

Molecular cloning and characterization of the family of feline leucine-rich glioma-inactivated (LGI) genes, and mutational analysis in familial spontaneous epileptic cats

BACKGROUND

Leucine-rich glioma-inactivated (LGI) proteins play a critical role in synaptic transmission. Dysfunction of these genes and encoded proteins is associated with neurological disorders such as genetic epilepsy or autoimmune limbic encephalitis in animals and human. Familial spontaneous epileptic cats (FSECs) are the only feline strain and animal model of familial temporal lobe epilepsy. The seizure semiology of FSECs comprises recurrent limbic seizures with or without evolution into generalized epileptic seizures, while cats with antibodies against voltage-gated potassium channel complexed/LGI1 show limbic encephalitis and recurrent limbic seizures. However, it remains unclear whether the genetics underlying FSECs are associated with LGI family genes. In the present study, we cloned and characterized the feline LGI1-4 genes and examined their association with FSECs. Conventional PCR techniques were performed for cloning and mutational analysis. Characterization was predicted using bioinformatics software.

RESULTS

The cDNAs of feline LGI1-4 contained 1674-bp, 1650-bp, 1647-bp, and 1617-bp open reading frames, respectively, and encoded proteins comprising 557, 549, 548, and 538 amino acid residues, respectively. The feline LGI1-4 putative protein sequences showed high homology with Homo sapiens, Canis familiaris, Bos taurus, Sus scrofa, and Equus caballus (92%-100%). Mutational analysis in 8 FSECs and 8 controls for LGI family genes revealed 3 non-synonymous and 14 synonymous single nucleotide polymorphisms in the coding region. Only one non-synonymous single nucleotide polymorphism in LGI4 was found in 3 out of 8 FSECs. Using three separate computational tools, this mutation was not predicted to be disease causing. No co-segregation of the disease was found with any variant.

CONCLUSIONS

We cloned the cDNAs of the four feline LGI genes, analyzed the amino acid sequences, and revealed that epilepsy in FSEC is not a monogenic disorder associated with LGI genes.

Pharmacogenomics in epilepsy

•

Genetic variation can influence response to antiepileptic drug (AED) treatment through various effector processes.

•

Metabolism of many AEDs is mediated by the cytochrome P450 (CYP) family; some of the CYPs have allelic variants that may affect serum AED concentrations.

•

‘Precision medicine’ focuses on the identification of an underlying genetic aetiology allowing personalised therapeutic choices.

•

Certain human leukocyte antigen, HLA, alleles are associated with an increased risk of idiosyncratic adverse drug reactions.

•

New results are emerging from large-scale multinational efforts, likely imminently to add knowledge of value from a pharmacogenetic perspective.

There is high variability in the response to antiepileptic treatment across people with epilepsy. Genetic factors significantly contribute to such variability. Recent advances in the genetics and neurobiology of the epilepsies are establishing the basis for a new era in the treatment of epilepsy, focused on each individual and their specific epilepsy. Variation in response to antiepileptic drug treatment may arise from genetic variation in a range of gene categories, including genes affecting drug pharmacokinetics, and drug pharmacodynamics, but also genes held to actually cause the epilepsy itself.

From a purely pharmacogenetic perspective, there are few robust genetic findings with established evidence in epilepsy. Many findings are still controversial with anecdotal or less secure evidence and need further validation, e.g. variation in genes for transporter systems and antiepileptic drug targets. The increasing use of genetic sequencing and the results of large-scale collaborative projects may soon expand the established evidence.

Precision medicine treatments represent a growing area of interest, focussing on reversing or circumventing the pathophysiological effects of specific gene mutations. This could lead to a dramatic improvement of the effectiveness and safety of epilepsy treatments, by targeting the biological mechanisms responsible for epilepsy in each specific individual.

Whilst much has been written about epilepsy pharmacogenetics, there does now seem to be building momentum that promises to deliver results of use in clinic.

Whole Exome Sequencing in Pediatric Neurology Patients: Clinical Implications and Estimated Cost Analysis

Genetic heterogeneity in neurologic disorders has been an obstacle to phenotype-based diagnostic testing. The authors hypothesized that information compiled via whole exome sequencing will improve clinical diagnosis and management of pediatric neurology patients. The authors performed a retrospective chart review of patients evaluated in the University of Michigan Pediatric Neurology clinic between 6/2011 and 6/2015. The authors recorded previous diagnostic testing, indications for whole exome sequencing, and whole exome sequencing results. Whole exome sequencing was recommended for 135 patients and obtained in 53 patients. Insurance barriers often precluded whole exome sequencing. The most common indication for whole exome sequencing was neurodevelopmental disorders. Whole exome sequencing improved the presumptive diagnostic rate in the patient cohort from 25% to 48%. Clinical implications included family planning, medication selection, and systemic investigation. Compared to current second tier testing, whole exome sequencing can result in lower long-term charges and more timely diagnosis. Overcoming barriers related to whole exome sequencing insurance authorization could allow for more efficient and fruitful diagnostic neurological evaluations.

Therapeutic Approaches to Genetic Ion Channelopathies and Perspectives in Drug Discovery

In the human genome more than 400 genes encode ion channels, which are transmembrane proteins mediating ion fluxes across membranes. Being expressed in all cell types, they are involved in almost all physiological processes, including sense perception, neurotransmission, muscle contraction, secretion, immune response, cell proliferation, and differentiation. Due to the widespread tissue distribution of ion channels and their physiological functions, mutations in genes encoding ion channel subunits, or their interacting proteins, are responsible for inherited ion channelopathies. These diseases can range from common to very rare disorders and their severity can be mild, disabling, or life-threatening. In spite of this, ion channels are the primary target of only about 5% of the marketed drugs suggesting their potential in drug discovery. The current review summarizes the therapeutic management of the principal ion channelopathies of central and peripheral nervous system, heart, kidney, bone, skeletal muscle and pancreas, resulting from mutations in calcium, sodium, potassium, and chloride ion channels. For most channelopathies the therapy is mainly empirical and symptomatic, often limited by lack of efficacy and tolerability for a significant number of patients. Other channelopathies can exploit ion channel targeted drugs, such as marketed sodium channel blockers. Developing new and more specific therapeutic approaches is therefore required. To this aim, a major advancement in the pharmacotherapy of channelopathies has been the discovery that ion channel mutations lead to change in biophysics that can in turn specifically modify the sensitivity to drugs: this opens the way to a pharmacogenetics strategy, allowing the development of a personalized therapy with increased efficacy and reduced side effects. In addition, the identification of disease modifiers in ion channelopathies appears an alternative strategy to discover novel druggable targets.

Pharmacogenetics of antiepileptic drugs: A brief review

The goal of pharmacogenetic research is to assist clinicians in predicting patient response to medications when genetic variations are identified. The pharmacogenetic variation of antiepileptic drug response and side effects has yielded findings that have been included in drug labeling and guidelines. The goal of this review is to provide a brief overview of the pharmacogenetic research on antiepileptic drugs. It will focus on findings that have been included in drug labeling, guidelines, and candidate pharmacogenetic variation. Overall, several genes have been included in guidelines by national and international organizations; however, much work is needed to implement and evaluate their use in clinical settings.

Pharmacological considerations in the use of stiripentol for the treatment of epilepsy

INTRODUCTION

Despite the fact that more than 20 antiepileptic drugs (AEDs) are currently available, about one-third of patients still present drug resistance. Further efforts are required to develop novel and more efficacious therapeutic strategies, especially for refractory epileptic syndromes showing few and anecdotic therapeutic options.

AREAS COVERED

Stiripentol (STP) is a second generation AED that shows GABAergic activity, with immature brain selectivity, and an indirect metabolic action on co-administered AEDs. Two pivotal studies demonstrated STP efficacy in patients with Dravet syndrome with refractory partial seizures, and marketing authorization in Europe, Canada and Japan was granted thereafter. Post-marketing surveys reported a good efficacy and tolerability profile. In addition, interesting data is currently emerging regarding off-label experimentation of STP in other forms of epilepsy.

EXPERT OPINION

STP is an important addition to the limited treatment options available for patients resistant to common AEDs. The possibility to inhibit seizures through the metabolic pathway of lactate dehydrogenase and the inhibitory effects on the entry of Na(+) and Ca(2+) are the most recent findings to emerge about STP and could be proof of its neuroprotective action. Moreover, its positive effects on cognitive function, its good safety and tolerability profile and the increasing data about STP efficacy on other refractory epileptic syndromes may prove to be fertile grounds for further investigation.

Incorporating Natural Products, Pharmaceutical Drugs, Self-Care and Digital/Mobile Health Technologies into Molecular-Behavioral Combination Therapies for Chronic Diseases

Merging pharmaceutical and digital (mobile health, mHealth) ingredients to create new therapies for chronic diseases offers unique opportunities for natural products such as omega-3 polyunsaturated fatty acids (n-3 PUFA), curcumin, resveratrol, theanine, or α-lipoic acid. These compounds, when combined with pharmaceutical drugs, show improved efficacy and safety in preclinical and clinical studies of epilepsy, neuropathic pain, osteoarthritis, depression, schizophrenia, diabetes and cancer. Their additional clinical benefits include reducing levels of TNFα and other inflammatory cytokines. We describe how pleiotropic natural products can be developed as bioactive incentives within the network pharmacology together with pharmaceutical drugs and self-care interventions. Since approximately 50% of chronically-ill patients do not take pharmaceutical drugs as prescribed, psychobehavioral incentives may appeal to patients at risk for medication non-adherence. For epilepsy, the incentive-based network therapy comprises anticonvulsant drugs, antiseizure natural products (n-3 PUFA, curcumin or/and resveratrol) coupled with disease-specific behavioral interventions delivered by mobile medical apps. The add-on combination of antiseizure natural products and mHealth supports patient empowerment and intrinsic motivation by having a choice in self-care behaviors. The incentivized therapies offer opportunities: (1) to improve clinical efficacy and safety of existing drugs, (2) to catalyze patient-centered, disease self-management and behavior-changing habits, also improving health-related quality-of-life after reaching remission, and (3) merging copyrighted mHealth software with natural products, thus establishing an intellectual property protection of medical treatments comprising the natural products existing in public domain and currently promoted as dietary supplements. Taken together, clinical research on synergies between existing drugs and pleiotropic natural products, and their integration with self-care, music and mHealth, expands precision/personalized medicine strategies for chronic diseases via pharmacological-behavioral combination therapies.

The pharmacogenomics of epilepsy

Genetic factors contribute to the high interindividual variability in response to antiepileptic drugs. However, most genetic markers identified to date have limited sensitivity and specificity, and the value of genetic testing in guiding antiepileptic drug (AED) therapy is limited. The best defined indication for testing relates to HLA-B*15:02 genotyping to identify those individuals of South Asian ethnicity who are at high risk for developing serious adverse cutaneous reactions to carbamazepine. The indication for HLA-A*31:01 testing to identify individuals at risk for skin reactions from carbamazepine, or for CYP2C9 genotyping to identify individuals at risk for serious skin reactions from phenytoin is less compelling. The use of genetic testing to guide epilepsy treatment is likely to increase in the future, as better understanding of the function of epilepsy genes will permit the application of precision medicine targeting the biological mechanisms responsible for epilepsy in the specific individual.