Evaluation of the anticonvulsant and neuroprotective effect of intracerebral administration of growth hormone in rats / Evaluación del efecto anticonvulsivante y neuroprotector de la administración intracerebral de la hormona de crecimiento en ratas

Introduction The growth hormone (GH) has been reported as a crucial neuronal survival factor in the hippocampus against insults of diverse nature. Status epilepticus (SE) is a prolonged seizure that produces extensive neuronal cell death. The goal of this study was to evaluate the effect of intracerebroventricular administration of GH on seizure severity and SE-induced hippocampal neurodegeneration. Methodology Adult male rats were implanted with a guide cannula in the left ventricle and different amounts of GH (70, 120 or 220 ng/3 μl) were microinjected for 5 days; artificial cerebrospinal fluid was used as the vehicle. Seizures were induced by the lithium–pilocarpine model (3 mEq/kg LiCl and 30 mg/kg pilocarpine hydrochloride) one day after the last GH administration. Neuronal injury was assessed by Fluoro-Jade B (F-JB) staining. Results Rats injected with 120 ng of GH did not had SE after 30 mg/kg pilocarpine, they required a higher number of pilocarpine injections to develop SE than the rats pretreated with the vehicle, 70 ng or 220 ng GH. Prefrontal and parietal cortex EEG recordings confirmed that latency to generalized seizures and SE was also significantly higher in the 120 ng group when compared with all the experimental groups. FJ-B positive cells were detected in the hippocampus after SE in all rats, and no significant differences in the number of F-JB cells in the CA1 area and the hilus was observed between experimental groups. Conclusion Our results indicate that, although GH has an anticonvulsive effect in the lithium–pilocarpine model of SE, it does not exert hippocampal neuroprotection after SE. (AU)

Introducción La hormona de crecimiento (HC) es un factor que favorece la supervivencia neuronal en el hipocampo ante agresiones de diversa naturaleza. El status epilepticus (SE) es un tipo de crisis epiléptica de larga duración que produce muerte neuronal. El objetivo de este estudio fue evaluar el efecto de la administración intracerebroventricular de HC en la severidad de las convulsiones y la neurodegeneración hipocampal debida al SE. Metodología A ratas macho adultas se les implantó una cánula guía en el ventrículo lateral izquierdo y se les microinyectaron diferentes cantidades de HC (70, 120 o 220 ng/3 μl) durante 5 días; como vehículo se inyectó líquido cefalorraquídeo artificial. Las convulsiones se generaron con el modelo de litio-pilocarpina (3 mEq/kg LiCl y 30 mg/kg clorhidrato pilocarpina) un día después de la última inyección de HC. La neurodegeneración se identificó con la tinción de Fluoro-Jade B (F-JB). Resultados Las ratas a las que se les inyectaron 120 ng de HC requirieron 2 o 3 inyecciones de pilocarpina para desarrollar SE, en comparación con el resto de los grupos experimentales que requirieron solo una aplicación del convulsivante. Los registros EEG de la corteza prefrontal y parietal confirmaron que la latencia a las crisis generalizadas y al SE fue mayor en dicho grupo experimental. Todas las ratas con SE presentaron células positivas al FJ-B en el área CA1 e hilus del hipocampo, y no se identificaron diferencias entre los tratamientos. Conclusión Nuestros resultados muestran que, aunque la HC tiene un efecto anticonvulsivante, una vez que se ha desarrollado el SE no promueve neuroprotección en el hipocampo. (AU)

Transient targeting of hypothalamic orexin neurons alleviates seizures in a mouse model of epilepsy.

Lateral hypothalamic (LH) hypocretin/orexin neurons (HONs) control brain-wide electrical excitation. Abnormally high excitation produces epileptic seizures, which affect millions of people and need better treatments. HON population activity spikes from minute to minute, but the role of this in seizures is unknown. Here, we describe correlative and causal links between HON activity spikes and seizures. Applying temporally-targeted HON recordings and optogenetic silencing to a male mouse model of acute epilepsy, we found that pre-seizure HON activity predicts and controls the electrophysiology and behavioral pathology of subsequent seizures. No such links were detected for HON activity during seizures. Having thus defined the time window where HONs influence seizures, we targeted it with LH deep brain stimulation (DBS), which inhibited HON population activity, and produced seizure protection. Collectively, these results uncover a feature of brain activity linked to seizures, and demonstrate a proof-of-concept treatment that controls this feature and alleviates epilepsy.

Electroencephalographic profile of Salvia amarissima Ortega and amarisolide A in the absence and presence of PTZ-induced seizures in mice.

Salvia amarissima Ortega is a plant used in traditional medicine to treat CNS's affections. Despite its depressant properties in anxiety and fibromyalgia, there is no scientific evidence about its capability to control seizure activity. This study aimed to investigate the effects of the S. amarissima aqueous extract (SAAE) and its metabolite amarisolide A (AMA) on the electrocorticographic (ECoG) activity. The ECoG profiles were previously and concurrently analyzed to the pentylenetetrazole (85 mg/kg, i.p.)-induced seizure behavior after thirty min of the administration of several doses of the SAAE (1, 10, 30, and 100 mg/kg, i.p.) and two doses of AMA (0.5 and 1 mg/kg, i.p.). A dosage of AMA (1 mg/kg,i.p.) was selected to explore a possible mechanism of action by using antagonists of inhibitory receptors such as GABAA (picrotoxin, 1 mg/kg, i.p.) or 5-HT1A of serotonin (WAY100635, 1 mg/kg, i.p.). Significant changes in the frequency bands and the spectral power were observed after the treatment alone. Additionally, SAAE and AMA produced significant and dose-dependent anticonvulsant effects by reducing the incidence and severity of seizures and increasing latency or survival. Both antagonists prevented the effects of AMA in the severity score of seizures and survival during the tonic-clonic seizures. In conclusion, our preclinical data support that S. amarissima possesses anticonvulsant properties, in part due to the presence of amarisolide A, mediated by different inhibitory mechanisms of action. Our scientific evidence suggests that this Salvia species and amarisolide A are potential neuroprotective alternatives to control seizures in epilepsy therapy.

Polysaccharide-rich extract of Genipa americana leaves protects seizures and oxidative stress in the mice model of pentylenetetrazole-induced epilepsy.

Plant polysaccharides have biological activities in the brain and those obtained from Genipa americana leaves present antioxidant and anticonvulsant effects in the mice model of pentylenetetrazole (PTZ)-induced acute seizures. This study aimed to evaluate the polysaccharide-rich extract of Genipa americana leaves (PRE-Ga) in the models of acute seizures and chronic epilepsy (kindling) induced by PTZ. In the acute seizure model, male Swiss mice (25-35 g) received PRE-Ga (1 or 9 mg/kg; intraperitoneal- IP), alone or associated with diazepam (0.01 mg/kg), 30 min before induction of seizures with PTZ (70 mg/kg; IP). In the chronic epilepsy model, seizures were induced by PTZ (40 mg/kg) 30 min after treatment and in alternated days up to 30 days and evaluated by video. Brain areas (prefrontal cortex, hippocampus, striatum) were assessed for inflammatory and oxidative stress markers. Diazepam associated to PRE-Ga (9 mg/kg; i.p.) increased the latency of seizures in acute (222.4 ± 47.57 vs. saline: 62.00 ± 4.709 s) and chronic models (6.267 ± 0.502 vs. saline: 4.067 ± 0.407 s). In hippocampus, PRE-Ga (9 mg/kg) inhibited TNF-α (105.9 ± 5.38 vs. PTZ: 133.5 ± 7.62 pmol/g) and malondialdehyde (MDA) (473.6 ± 60.51) in the chronic model. PTZ increased glial fibrillar acid proteins (GFAP) and Iba-1 in hippocampus, which was reversed by PRE-Ga (GFAP: 1.9 ± 0.23 vs PTZ: 3.1 ± 1.3 and Iba-1: 2.2 ± 0.8 vs PTZ: 3.2 ± 1.4). PRE-Ga presents neuroprotector effect in the mice model of epilepsy induced by pentylenetetrazole reducing seizures, gliosis, inflammatory cytokines and oxidative stress.

Herb pair of Polygala tenuifolia Willd and Acorus tatarinowii Schott decoction attenuates seizures and alleviates anxiety in mice: Evidence for modulating inflammation, alleviating oxidative stress and mediating GABA pathway.

Currently, prolong use of standard anti-epileptics may cause tolerance and ineffective for about 30% of epileptic patients. Medicinal plants provide an attractive therapeutic effect in preventing and treating seizures in traditional and folk medicine. In this study, we investigate the antiepileptic effects of PTAT decoction on acute and chronic seizure models in mice and explore the potential mechanisms. PTAT decoction dose-dependently protected mice against MES and PTZ induced seizure. Meanwhile, it decreased the seizure severity and reduced seizure-caused anxious behavior in the PTZ-kindling mice, suggesting a significant antiepileptic activity and anxiolytic/anxiogenic potential. PTAT decoction dose-dependently increased the levels of GSH and the activity SOD and CAT, while decreased the level of MDA in the hippocampi of treated mice. Furthermore, a significant decrease in the proinflammatory cytokine levels, including TNF-α, IL-1ß, IL-6 and MCP-1 was found in treated mice compared with the mice in the vehicle + PTZ group. Moreover, PTAT decoction dose-dependently reversed the alterations induced by PTZ in GABA, GABA-T, L-GAD and glutamate levels in kindling mice, showing an effect on the modulation of the GABA neurotransmission. Thus, PTAT decoction has a promising anticonvulsant activity mediated via multiple mechanisms, which might be used as an up-and-coming phytotherapy strategy in the management of epilepsy and its complications.

Ameliorative effects of Albizia adianthifolia aqueous extract against pentylenetetrazole-induced epilepsy and associated memory loss in mice: Role of GABAergic, antioxidant defense and anti-inflammatory systems.

Albizia adianthifolia (Schumach.) (Fabaceae) is a medicinal herb used for the treatment of epilepsy and memory impairment. This study aims to investigate the anticonvulsant effects of Albizia adianthifolia aqueous extract against pentylenetetrazole (PTZ)-induced spontaneous convulsions in mice; and determine whether the extract could mitigate memory impairment, oxidative/nitrergic stress, GABA depletion and neuroinflammation. Ultra-high performance liquid chromatography/mass spectrometry analysis was done to identify active compounds from the extract. Mice were injected with PTZ once every 48 h until kindling was developed. Animals received distilled water for the normal group and negative control groups, doses of extract (40, 80, or 160 mg/kg) for the test groups and sodium valproate (300 mg/kg) for the positive control group. Memory was measured using Y maze, novel object recognition (NOR) and open field paradigms, while the oxidative/nitrosative stresses (MDA, GSH, CAT, SOD and NO), GABAergic transmission (GABA, GABA-T and GAD) and neuro-inflammation (TNF-α, IFN-γ, IL- 1ß, and IL-6) were determined. Brain photomicrograph was also studied. Apigenin, murrayanine and safranal were identified in the extract. The extract (80-160 mg/kg) significantly protected mice against seizures and mortality induced by PTZ. The extract significantly increased the spontaneous alternation and the discrimination index in the Y maze and NOR tests, respectively. PTZ kindling induced oxidative/nitrosative stress, GABA depletion, neuroinflammation and neuronal cells death was strongly reversed by the extract. The results suggest that the anticonvulsant activity of Albizia adianthifolia extract is accompanied by its anti-amnesic property, and may be supported by the amelioration of oxidative stress, GABAergic transmission and neuroinflammation.

Supplementation of n-3 PUFAs in Adulthood Attenuated Susceptibility to Pentylenetetrazol Induced Epilepsy in Mice Fed with n-3 PUFAs Deficient Diet in Early Life.

The growth and development of the fetus and newborn throughout pregnancy and lactation are directly related to the nutritional status of the mother, which has a significant impact on the health of the offspring. The purpose of this experiment was to investigate the susceptibility of n-3 polyunsaturated fatty acid deficiency in early life to seizures in adulthood. The n-3 PUFAs-deficient mice's offspring were established and then fed with α-LNA diet, DHA-enriched ethyl ester, and DHA-enriched phospholipid-containing diets for 17 days at the age of eight weeks. During this period, animals received intraperitoneal injections of 35 mg/kg of pentylenetetrazol (PTZ) every other day for eight days. The results showed that dietary n-3 PUFA-deficiency in early life could aggravate PTZ-induced epileptic seizures and brain disorders. Notably, nutritional supplementation with n-3 PUFAs in adulthood for 17 days could significantly recover the brain n-3 fatty acid and alleviate the epilepsy susceptibility as well as raise seizure threshold to different levels by mediating the neurotransmitter disturbance and mitochondria-dependent apoptosis, demyelination, and neuroinflammation status of the hippocampus. DHA-enriched phospholipid possessed a superior effect on alleviating the seizure compared to α-LNA and DHA-enriched ethyl ester. Dietary n-3 PUFA deficiency in early life increases the susceptibility to PTZ-induced epilepsy in adult offspring, and nutritional supplementation with n-3 PUFAs enhances the tolerance to the epileptic seizure.

Chemical composition and anticonvulsant activities of herb pair of Gastrodia elata Blume-Acorus tatarinowii Schott decoction on experimentally induced seizures in mice.

Epilepsy is a serious public health problem in the world. At present, over 30% of affected patients remain refractory to currently available treatment. Medicinal plants as pharmaceuticals and healthcare treatments have been frequently used in the management of epilepsy in China for many centuries. Gastrodia elata-Acous tatarinowii (GEAT), as a classic and most commonly used herb pair in traditional Chinese medicine (TCM), has been employed to control seizures for thousands of years. However, the animal experiment data on its anticonvulsant effect is limited in the literature. Thus, this study aimed to reveal the therapeutic actions of GEAT decoction against seizures in mice. UHPLC-MS/MS was performed to analyze the chemical components of GEAT decoction. The mice were given GEAT decoction for 7 days, and MES, PTZ, and 3-MP injection was given 30 min after the last administration. Video monitoring was performed for comparisons. In addition, the PTZ-induced kindling models were conducted to investigate the seizure severity, anxiety and cognitive profile, inflammation, and oxidative stress parameters in mice. The results showed that GEAT decoction dose-dependently protected mice against MES, 3-MP, and PTZ-induced acute seizures. Furthermore, GEAT decoction significantly ameliorated seizure severity, decreased the accumulation of inflammatory mediators TNF-α, IL-1ß, and IL-6, mitigated oxidative stress, as well as alleviated anxious-like behavior and cognitive deficits in PTZ-kindled mice. These results suggest that GEAT decoction possesses certain anticonvulsant properties, which might be clinically useful as phytotherapy alone or as an adjunct therapy for the prevention and treatment of seizures and epilepsy.

A randomized controlled trial of loading dose alone versus pritchard regimen of magnesium sulphate, for seizure prophylaxis in severe preeclampsia.

Background: Preeclampsia poses a significant risk of maternal and neonatal morbidity and mortality. Magnesium sulfate superiority for seizure prophylaxis in severe preeclampsia has been proven globally. However, the search for the lowest effective dose is an area of continuing research. Aim: The aim of this study was to compare the effectiveness of loading dose with the Pritchard regimen of magnesium sulfate for seizure prophylaxis in severe preeclampsia. Materials and Methods: A total of 138 eligible women after 28-week gestation with severe preeclampsia were randomized to either receiving a single loading dose of MgSO4 (study arm: n = 69) or Pritchard regimen of MgSO4 (control: n = 69). The effectiveness was assessed by the development of seizure. The results obtained were analyzed using SPSS version 21. Categorical variables were analyzed using the Chi-square test and normally distributed continuous variables were analyzed with t-test and Fisher's exact test. P < 0.05 was considered statistical significance. Results: There were no significant differences between those who received only the loading dose when compared with those who had Pritchard regimen other than a single recorded convulsion among the control group (P = 0.316). Similarly, except for the duration of hospital stay which was significantly longer in the Pritchard group (P = 0.019), both the arms of the study shared similar maternal and fetal outcomes. Conclusion: This study suggests the effectiveness of just the loading dose of magnesium sulfate when compared with the standardized Pritchard regimen in the prevention of seizure among women with severe preeclampsia. The study also demonstrated safety and similarity in fetal-maternal outcome. The loading dose only had an added advantage of shorter duration of hospital stay.

Résumé Contexte: La prééclampsie pose un risque important de morbidité et de mortalité maternelle et néonatale. La supériorité du sulfate de magnésium pour 15 prophylaxies épileptiques dans la prééclampsie sévère a été prouvée à l'échelle mondiale. Cependant, la recherche de la dose efficace la plus faible est un domaine de recherche continue. Objectif: L'objectif de cette étude était de comparer l'efficacité de la dose de charge avec le schéma de Pritchard de sulfate de magnésium pour la prophylaxie de 17 épilepsies dans la prééclampsie sévère. Matériels et méthodes: Un total de 138 femmes éligibles après 28 semaines de gestation atteintes de 18 prééclampsie ont été randomisés pour recevoir soit une dose de charge unique de MgSO4 (groupe d'étude : n = 69) soit un régime de Pritchard de MgSO4 (contrôle : n = 69). L'efficacité a été évaluée par le développement de saisie. Les résultats obtenus ont été analysés à l'aide de SPSS version 21. Les 19 variables catégorielles ont été analysées à l'aide du test du chi carré et les variables continues normalement distribuées ont été analysées à l'aide du test t et du test exact de Fisher. 20 P < 0,05 était considéré comme une signification statistique. Résultats: Il n'y avait pas de différences significatives entre ceux qui n'avaient reçu que la dose de charge 21 par rapport à ceux qui avaient reçu le régime de Pritchard autre qu'une seule convulsion enregistrée parmi le groupe témoin (P = 0,316). 22 De même, à l'exception de la durée du séjour à l'hôpital qui était significativement plus longue dans le groupe Pritchard (P = 0,019), les deux bras de l'étude 23 partageaient des résultats maternels et fœtaux similaires. Conclusion: Cette étude suggère l'efficacité de la seule dose de charge de sulfate de magnésium par rapport au régime de Pritchard standardisé dans la prévention des convulsions chez les femmes atteintes de prééclampsie sévère. L'étude a également démontré 24 l'innocuité et la similarité des résultats fœto-maternels. La dose de charge n'avait qu'un avantage supplémentaire de durée d'hospitalisation plus courte. 25. Mots-clés: Éclampsie, dose de charge, sulfate de magnésium, régime de Pritchard, prophylaxie des crises, prééclampsie sévère.

Zinc Water Prevents Autism-Like Behaviors in the BTBR Mice.

This study aims to explore the effects of zinc water on autism-like behavior, convulsion threshold, and neurogenesis in ASD model animals. This study used the young BTBR ASD mouse model to explore the effect of a 6-week zinc water supplementation on ASD-like behaviors such as repetitive behavior and social communication disorder, seizure threshold, and the correlation with excitability regulation. The mice were divided into four groups of normal controls (B6) and models (BTBR) who did and did not receive zinc supplementation in water (B6, B6 + zinc, BTBR, and BTBR + zinc). For morphological changes in the hippocampus, we selected two indicators: hippocampal mossy fiber sprouting and neurogenesis. ASD-like behavior testing, seizure threshold determination, Timm staining, and neurogenesis-related assays-represented by Ki67 and DCX-were performed after 6 weeks of zinc supplementation. Our results show that zinc water can prevent autism-like behavior, reduce susceptibility to convulsions, and increase the proliferation of hippocampal progenitor cells in BTBR mice but has less effect on mossy fiber sprouting and neural progenitor cell differentiation. Zinc water reduces autism-like behavior in a partially inherited autism model mice-BTBR-which may be associated with hippocampal neural precursor cell proliferation and reversed hyperexcitability.

The Neuroprotective Effect Associated with Echinops spinosus in an Acute Seizure Model Induced by Pentylenetetrazole.

Echinops spinosus (ES) is a medicinal plant with a wide range of pharmacological and biological effects. It is a medicinal herb having a variety of therapeutic characteristics, including antioxidant, anti-inflammatory, and antibacterial capabilities. The primary goal of this research is to investigate the neuroprotective and anticonvulsant characteristics of E. spinosa extract (ESE) against pentylenetetrazole (PTZ)-induced acute seizures. Negative control rats, ESE treatment rats, PTZ acute seizure model rats, ESE + PTZ rats, and Diazepam + PTZ rats were used in the study. The rats were given a 7-day treatment. ESE pretreatment elevated the latency to seizure onset and lowered seizure duration after PTZ injection. By reducing Bax levels and enhancing antiapoptotic Bcl-2 production, ESE prevented the release of interleukin-1ß, tumor necrosis factor-α, and cyclooxygenase-2, as well as preventing hippocampal cell death after PTZ injection. ESE corrected the PTZ-induced imbalance in gamma-aminobutyric acid levels and increased the enzyme activity of Na+/K+-ATPase. Echinops spinosus is a potent neuromodulatory, antioxidant, antiinflammatory, and antiapoptotic plant that could be employed as a natural anticonvulsant in the future.

Stem bark chloroform extract of Bombax costatum Pellegr. & Vuillet exhibit anticonvulsant and neuroprotective effects in pentylenetetrazole-induced seizures in rats.

AIM OF THE STUDY: The study aimed at evaluating the potentials of stem bark extracts of Bombax costatum (B. costatum) on seizure, pentylenetetrazole (PTZ) induced kindling and associated changes in wistar albino rats. MATERIALS AND METHODS: Phase 1 evaluated which extract of B. costatum (chloroform, ethanol and n-hexane) is most effective in preventing seizure in acute PTZ-induced (85mg/kg) seizure in rats. Phase 2 evaluated the potentials of stem bark chloroform extract of B. costatum in PTZ-kindled rats at a dose 250 and 500mg/kg in comparison to diazepam. As its effects on memory, oxidative stress markers, neurotransmitters and brain histology were evaluated. Phase 3 determined the probable curative effects of B. costatum on fully kindled rats. RESULTS: In phase 1, Chloroform extract of B. coststum 500mg/kg is the most effective (P<0.05) in preventing seizure as compared to ethanol and n-hexane extracts. In phase 2, chloroform extract of B. costatum delayed the development of kindling, improved kindling associated cognitive impairment and alterations of glutamate and gamma-aminobutyric acid (GABA). Further, it attenuated oxidative stress besides the maintenance of neuronal architecture of the hippocampus. CONCLUSION: Conclusively, chloroform stem bark extract of B. costatum antagonizes PTZ-induced seizure progression, protects against kindling induced cognitive impairment and oxidative stress. Additionally, it also increases the brain level of GABA at high dose and prevented against kindling-induced hippocampal disruptions. Hence, this justifies its use traditionally in the treatment of epileptic seizures.

Efficacy of supplemental MCT oil on seizure reduction of adult drug-resistant epilepsy - a single-center open-label pilot study.

OBJECTIVE: We set out to determine whether adding medium chain triglyceride (MCT) oil as a dietary supplement to standard diet in adult subjects with intractable epilepsy in a U.S. neurology clinical practice was associated with a reduction in number of seizures. We secondarily aimed to determine whether subjects experienced any side effects and whether there was a presence of urinary ketones while using MCT oil as a dietary supplement. METHODS: Adult patients with intractable epilepsy were recruited at standard of care clinical visits with their epileptologist. Once enrolled, subjects were instructed to supplement their diet with MCT oil as tolerated twice daily for three months (including a 1-2 week titration period, followed by a 1-2 week tapering off window) while keeping a seizure diary to record total number of seizures, presence of urinary ketones, and any side effects. RESULTS: Our data although limited by small sample size, shows that there is an estimated 42% reduction (p < 0.0001) in the rate of seizures. The MCT oil supplementation was well tolerated by most subjects except for minor GI side effects like nausea and loose stools. Most subjects developed ketones in their urine at some point during the trial. CONCLUSIONS: MCT oil supplementation reduced seizure frequency in study participants. The reported side effects included mild nausea, stomachache, loose stools. A placebo-controlled study will be more informative.

Digoxin at sub-cardiotonic dose modulates the anticonvulsive potential of valproate, levetiracetam and topiramate in experimental primary generalized seizures.

The prevalence of epilepsy in the world population together with a high percentage of patients resistant to existing antiepileptic drugs (AEDs) stimulates the constant search for new approaches to the treatment of the disease. Previously a significant anticonvulsant potential of cardiac glycoside digoxin has been verified by enhancing a weak activity of AEDs in low doses under screening models of seizures induced by pentylenetetrazole and maximal electroshock. The aim of the present study is to investigate the influence of digoxin at a sub-cardiotonic dose on the anticonvulsant activity of valproate, levetiracetam, and topiramate in models of primary generalized seizures with different neurochemical mechanisms. A total of 264 random-bred male albino mice have been used. AEDs were administered 30 min before seizure induction once intragastrically at conditionally effective (ED50) and sub-effective (½ ED50) doses: sodium valproate and topiramate - at doses of 300 and 150 mg/kg; levetiracetam - at doses of 100 and 50 mg/kg. Digoxin was administered once subcutaneously at a dose of 0.8 mg/kg body weight (1/10 LD50) 10-15 min before seizure induction. Picrotoxin (aqueous solution 2.5 mg/kg, subcutaneously), thiosemicarbazide (aqueous solution 25 mg/kg, intraperitoneally), strychnine (aqueous solution 1.2 mg/kg, subcutaneously), camphor (oil solution 1000 mg/kg, intraperitoneally) have been used as convulsive agents for seizure induction. It was found that under the conditions of primary generalized seizures induced by picrotoxin, thiosemicarbazide, strychnine, and camphor, digoxin not only shows its own strong anticonvulsant activity but also significantly enhances the anticonvulsant potential of classical AEDs sodium valproate, levetiracetam, and topiramate. The obtained results substantiate the expediency of further in-depth study of digoxin as an anticonvulsant drug, in particular, the in-depth study of neurochemical mechanisms of its action.

Incident epilepsy in the cognitively normal geriatric population, irrespective of seizure control, impairs quality of life.

PURPOSE OF THE RESEARCH: The geriatric population is the fastest-growing population in the United States and the impact of incident epilepsy on the cognitively intact geriatric population is not well-studied. Understanding how epilepsy affects the elderly is important to improve the quality of treatment and care for our aging population. This study sought to address the impact of incident epilepsy on the perceived Quality of Life (QOL) in cognitively intact elderly using the SF-36 questionnaire. METHODS: Nine hundred and twenty-seven participants were assessed from a community-based cohort. Based on a history of subsequent development of new-onset seizures, participants were divided into two groups, an incident seizure group that developed new-onset seizures after 65 years of age and the control group without incident seizures. Of this, six hundred eleven were analyzed with the SF-36 questionnaire after excluding for cognitive decline and inconsistent medical data. PRINCIPAL RESULTS: Statistically significant differences were found in 9 items on SF-36, involving perception of increased physical disability (p < 0.01; t-test), frailty (p < 0.04; t-test), emotional health limitations (p < 0.03; t-test), anxiety and sadness (p < 0.04; t-test), problems interfering with social activities (p < 0.0001; t-test). No between-group differences were found for demographic variables including age, education, gender, or minority status. Among the 611 subjects who remained cognitively normal across all longitudinal visits, 12 reported a history of new-onset seizures. Ten of these 12 subjects were seizure free as a result of treatment, with only 2 experiencing recent seizures. The incidence of seizures in our population was 300 per 100,000 person years. MAJOR CONCLUSIONS: This study identified the elderly population with incident epilepsy as a subgroup with an unmet health need, and healthcare professionals should address the potential impact of seizures with their geriatric patients to ensure comprehensive care.

The bee venom active compound melittin protects against bicuculline-induced seizures and hippocampal astrocyte activation in rats.

Epilepsy is a chronic neuropathology characterized by an abnormal hyperactivity of neurons that generate recurrent, spontaneous, paradoxical and synchronized nerve impulses, leading or not to seizures. This neurological disorder affects around 70 million individuals worldwide. Pharmacoresistance is observed in about 30% of the patients and long-term use of antiepileptics may induce serious side effects. Thus, there is an interest in the study of the therapeutic potential of bioactive substances isolated from natural products in the treatment of epilepsy. Arthropod venoms contain neurotoxins that have high affinity for molecular structures in the neural tissue such as receptors, transporters and ion channels both in glial and neuronal membranes. This study evaluated the potential neuroprotective effect of melittin (MEL), an active compound of bee venom, in the bicuculline-induced seizure model (BIC) in rats. Male Wistar rats (3 months, 250-300 g) were submitted to surgery for the implantation of a unilateral cannula in the lateral ventricle. After the recovery period, rats received a microinjection of saline solution or MEL (0.1 mg per animal). Firstly, rats were evaluated in the open field (20 min) and in the elevated plus maze (5 min) tests after received microinjection of saline or MEL. After, 30 min later animals received BIC (100 mg/ml) or saline, and their behaviors were analyzed for 20 min in the open field according to a seizure scale. At the end, rats were euthanized, brains collected and processed to glial fibrillary acidic protein (GFAP) immunohistochemistry evaluation. No changes were observed in MEL-treated rats in the open field and elevated plus maze. However, 90% of MEL-treated animals were protected against seizures induced by BIC. There was an increase in the latency for the onset of seizures, accompanied by a reduction of GFAP-immunoreactivity cells in the dentate gyrus and CA1. Thus, our study suggests that MEL has an anticonvulsant potential, and further studies are needed to elucidate the mechanisms involved in this action.

Dietary omega-3 fatty acids prevent neonatal seizure-induced early alterations in the hippocampal glutamatergic system and memory deficits in adulthood.

OBJECTIVE: We investigated the influence of dietary omega-3 polyunsaturated fatty acids (n-3 PUFAs) on glutamatergic system modulation after a single episode of neonatal seizures and their possible effects on seizure-induced long-lasting behavioral deficits. METHODS: Male Wistar rats receiving an omega-3 diet (n-3) or an n-3 deficient diet (D) from the prenatal period were subjected to a kainate-induced seizure model at P7. Glutamate transporter activity and immunocontents (GLT-1 and GLAST) were assessed in the hippocampus at 12, 24, and 48 h after the seizure episode. Fluorescence intensity for glial cells (GFAP) and neurons (NeuN) was assessed 24 h after seizure in the hippocampus. Behavioral analysis (elevated-plus maze and inhibitory avoidance memory task) was performed at 60 days of age. RESULTS: The D group showed a decrease in glutamate uptake 24 h after seizure. In this group only, the GLT1 content increased at 12 h, followed by a decrease at 24 h. GLAST increased up to 24 h after seizure. GFAP fluorescence was higher, and NeuN fluorescence decreased, in the D group independent of seizures. In adulthood, the D group presented memory deficits independent of seizures, but short-term memory (1.5 h after a training session) was abolished in the D group treated with kainate. SIGNIFICANCE: N-3 PUFA positively influenced the glutamatergic system during seizure and prevented seizure-related memory deficits in adulthood.

The effect of omega-3 fatty acid supplementation on seizure frequency in individuals with epilepsy: a systematic review and meta-analysis.

BACKGROUND: Although there is ample evidence for the effect of omega-3 supplementation on seizure frequency in individuals with epilepsy, the results are inconsistent. Therefore, we conducted this systematic review and meta-analysis to elucidate the potential effect of omega-3 supplementation in the adult and pediatric population. METHODS: Clinical trials articles were searched in electronic databases (Web of Science, Scopus, PubMed/Medline, Embase, and Google Scholar database up to October 2020). No language limitation was imposed in the literature search. Moreover, gray literature search was done via searching the references of identified review papers to find more potentially relevant articles. RESULTS: In order, the duration of the intervention and dosage of omega-3 fatty acid supplement of the included studies ranged from 12 to 42 weeks and 1000-2880 mg/day. Pooled results from the random-effects model indicated that seizure frequency following supplementation of omega-3 fatty acid decreased significantly (WMD: -6.15, 95% CI: -7.78, -4.53, P < 0.001). Furthermore, the results of the subgroup analysis revealed that seizure frequency was more alleviated in studies that used a daily dose of 1500 mg or less of omega-3 fatty acids as well as studies that had an intervention duration of more than 16 weeks. More importantly, our findings also showed that the effect of omega-3 intervention was greater in adults than in children with epilepsy. CONCLUSION: The current meta-analysis on available trials suggested that omega-3 supplementation resulted in beneficial effects on seizure frequency in adult and children with epilepsy.

Thalamic deep brain stimulation modulates cycles of seizure risk in epilepsy.

Chronic brain recordings suggest that seizure risk is not uniform, but rather varies systematically relative to daily (circadian) and multiday (multidien) cycles. Here, one human and seven dogs with naturally occurring epilepsy had continuous intracranial EEG (median 298 days) using novel implantable sensing and stimulation devices. Two pet dogs and the human subject received concurrent thalamic deep brain stimulation (DBS) over multiple months. All subjects had circadian and multiday cycles in the rate of interictal epileptiform spikes (IES). There was seizure phase locking to circadian and multiday IES cycles in five and seven out of eight subjects, respectively. Thalamic DBS modified circadian (all 3 subjects) and multiday (analysis limited to the human participant) IES cycles. DBS modified seizure clustering and circadian phase locking in the human subject. Multiscale cycles in brain excitability and seizure risk are features of human and canine epilepsy and are modifiable by thalamic DBS.

Comparative Antiseizure Analysis of Diverse Natural Coumarin Derivatives in Zebrafish.

Coumarins are a well-known group of plant secondary metabolites with various pharmacological activities, including antiseizure activity. In the search for new antiseizure drugs (ASDs) to treat epilepsy, it is yet unclear which types of coumarins are particularly interesting as a systematic analysis has not been reported. The current study performed behavioral antiseizure activity screening of 18 different coumarin derivatives in the larval zebrafish pentylenetetrazole (PTZ) model using locomotor measurements. Activity was confirmed for seven compounds, which lowered seizure-like behavior as follows: oxypeucedanin 38%, oxypeucedanin hydrate 74%, notopterol 54%, nodakenetin 29%, hyuganin C 35%, daphnoretin 65%, and pimpinellin 60%. These coumarins, together with nodakenin, underwent further antiepileptiform analysis by local field potential recordings from the zebrafish opticum tectum (midbrain). All of them, except for nodakenetin, showed pronounced antiepileptiform activity, decreasing PTZ-induced elevation in power spectral density (PSD) by 83-89% for oxypeucedanin, oxypeucedanin hydrate, and notopterol, 77% for nodakenin, 26% for nodakenetin, 65% for hyuganin C, 88% for daphnoretin, and 81% for pimpinellin. These data demonstrate the potential of diverse coumarin scaffolds for ASD discovery. Finally, the structural differences between active and inactive coumarins were investigated in silico for oxypeucedanin hydrate and byacangelicin for their interaction with GABA-transaminase, a hypothetical target.