Evaluating a Venom-Bioinspired Peptide, NOR-1202, as an Antiepileptic Treatment in Male Mice Models.

Epilepsy, a neurological disorder characterized by excessive neuronal activity and synchronized electrical discharges, ranks among the most prevalent global neurological conditions. Despite common use, antiepileptic drugs often result in adverse effects and lack effectiveness in controlling seizures in temporal lobe epilepsy (TLE) patients. Recent research explored the potential of occidentalin-1202, a peptide inspired by Polybia occidentalis venom, in safeguarding Wistar rats from chemically induced seizures. The present study evaluated the new analog from occidentalin-1202 named NOR-1202 using acute and chronic pilocarpine-induced models and an acute kainic acid (KA) male mice model. NOR-1202 was administered through the intracerebroventricular (i.c.v.), subcutaneous, or intraperitoneal routes, with stereotaxic procedures for the i.c.v. injection. In the acute pilocarpine-induced model, NOR-1202 (i.c.v.) protected against generalized seizures and mortality but lacked systemic antiepileptic activity. In the KA model, it did not prevent generalized seizures but improved survival. In the chronic TLE model, NOR-1202's ED50 did not differ significantly from the epileptic or healthy groups regarding time spent in spontaneous recurrent seizures during the five-day treatment. However, the NOR-1202 group exhibited more seizures than the healthy group on the second day of treatment. In summary, NOR-1202 exhibits antiepileptic effects against chemoconvulsant-induced seizures, but no effect was observed when administered systemically.

Silencing of the GluN1-NMDA Glutamate Receptor Subunit by Intranasal siRNA Increases the Latency Time for Seizures in the Pilocarpine Rodent Model of Epilepsy.

Temporal lobe epilepsy (TLE) is the most prevalent and treatment-refractory type of epilepsy. Among the different mechanisms associated with epileptogenesis, overstimulation of glutamatergic neurotransmission has been associated with the onset and progression of seizures in TLE. Experimental evidence indicates that blocking the N-methyl-D-aspartate (NMDA) receptor or suppressing the expression of its subunit, mainly GluN1, may be effective in preventing epileptic seizures. Small interfering RNA (siRNA) has received attention as a potential therapeutic tool due to the inhibition of gene expression in some diseases. The present work evaluated the potential silencing effect of intranasal administration of an siRNA conjugate against the GluN1 subunit in animals submitted to the pilocarpine model of epilepsy. The results showed that the siRNA conjugate transfection system silences the GluN1 subunit in the hippocampus of rats when administered intranasally. As demonstrated by the RT-qPCR and Western blotting approaches, the silencing of GluN1 was specific for this subunit without affecting the amount of mRNA for other subunits. Silencing increased the latency time for the first tonic-clonic seizure when compared to controls. The overlapping of findings and the validation of the intranasal route as a pharmacological route of siRNA targeting the GluN1 subunit give the work a significant biotechnological interest.

Pilocarpine-induced seizures associate with modifications of LSD1/CoREST/HDAC1/2 epigenetic complex and repressive chromatin in mice hippocampus.

Epilepsy is a neurological disorder of genetic or environmental origin characterized by recurrent spontaneous seizures. A rodent model of temporal lobe epilepsy is induced by a single administration of pilocarpine, a non-selective cholinergic muscarinic receptor agonist. The molecular changes associated with pilocarpine-induced seizures are still poorly described. Epigenetic multiprotein complexes that regulate gene expression by changing the structure of chromatin impose transcriptional memories. Among the epigenetic enzymes relevant to the epileptogenic process is lysine-specific demethylase 1 (LSD1, KDM1A), which regulates the expression of genes that control neuronal excitability. LSD1 forms complexes with the CoREST family of transcriptional corepressors, which are molecular bridges that bring HDAC1/2 and LSD1 enzymes to deacetylate and demethylate the tail of nucleosomal histone H3. To test the hypothesis that LSD1-complexes are involved in initial modifications associated with pilocarpine-induced epilepsy, we studied the expression of main components of LSD1-complexes and the associated epigenetic marks on isolated neurons and the hippocampus of pilocarpine-treated mice. Using a single injection of 300 mg/kg of pilocarpine and after 24 h, we found that protein levels of LSD1, CoREST2, and HDAC1/2 increased, while CoREST1 decreased in the hippocampus. In addition, we observed increased histone H3 lysine 9 di- and trimethylation (H3K9me2/3) and decreased histone H3 lysine 4 di and trimethylation (H3K4me2/3). Similar findings were observed in cultured hippocampal neurons and HT-22 hippocampal cell line treated with pilocarpine. In conclusion, our data show that muscarinic receptor activation by pilocarpine induces a global repressive state of chromatin and prevalence of LSD1-CoREST2 epigenetic complexes, modifications that could underlie the pathophysiological processes leading to epilepsy.

Determination of the Initial Abnormal Discharge Site in Temporal Lobe Epilepsy Through Combined EEG and Neuroimaging. What Is Next?

Objective: The objective of this study was to determine the relationship between atrophy of the hippocampus and severity of epilepsy in patients with temporal lobe epilepsy (TLE) as the first step to evaluate the possibility of surgery for epilepsy and analyze why patients cannot undergo epilepsy surgery. Methods: Volumetric MRI of the hippocampus was performed in 51 consecutive patients (29 men; mean age 40) with TLE. TLE diagnosis, lateralization, and severity (mild, moderate, severe) of seizures were based on a comprehensive evaluation that included neurologic examination and EEG in all patients. Patients with evidence of a lesion other than hippocampal sclerosis were not included in the study. We assessed the relationship between hippocampal volumes and electrophysiological evidence of seizure severity. Results: According to the affected side based on the EEG, a statistically significant difference (p < 0.001) in volume and a positive correlation between epilepsy and hippocampal atrophy were found. Conclusion: Our results confirm that volume loss to the hippocampus in patients with TLE correlates with the severity of epilepsy based on the EEG. Therefore, surgical treatment is considered early when hippocampal atrophy is evident in patients with refractory TLE. However, in Latin American countries, it is a challenge to get a patient to undergo epilepsy surgery. Therefore, we try to analyze the sad situation in our hospital.

Behavioral and EEGraphic Characterization of the Anticonvulsant Effects of the Predator Odor (TMT) in the Amygdala Rapid Kindling, a Model of Temporal Lobe Epilepsy.

Background: Clinical and experimental evidence indicates that olfactory stimulation modulates limbic seizures, either blocking or inducing ictal activity. Objective: We aim to evaluate the behavioral and electroencephalographic (EEGraphic) effects of dihydro-2,4,5-trimethylthiazoline (TMT) olfactory exposure on limbic seizures induced by amygdala rapid kindling (ARK). Materials and Methods: Wistar male rats (280-300 g) underwent stereotaxic surgery for electrode implantation in piriform cortex (PC), hippocampal formation (HIP), and amygdaloid complex (AMYG). Part of the animals was exposed to a saturated chamber with water or TMT, while others had ARK and olfactory exposure prior to the 21st stimulus. Behavioral responses were measured by traditional seizure severity scales (Racine and Pinel and Rovner) and/or by sequential analysis/neuroethology. The electrographic activity of epileptogenic limbic networks was quantified by the occurrence of the first and second EEG afterdischarges, comparing the 1st and 21st stimulus. The spectral analysis [Fast Fourier Transform (FFT)] of the first afterdischarge was performed at the 21st stimulus. Results: TMT olfactory exposure reduced the seizure severity in kindled rats, altering the displayed behavioral sequence. Moreover, TMT decreased the occurrence of first and second afterdischarges, at the 21st stimulus, and altered the spectral features. Conclusions: Both behavioral and EEGraphic evaluations indicated that TMT, a potent molecule with strong biological relevance, in fact, "predator odor," suppressed the epileptiform activity in limbic networks.

New Insights on Temporal Lobe Epilepsy Based on Plasticity-Related Network Changes and High-Order Statistics.

Epilepsy is a disorder of the brain characterized by the predisposition to generate recurrent unprovoked seizures, which involves reshaping of neuronal circuitries based on intense neuronal activity. In this review, we first detailed the regulation of plasticity-associated genes, such as ARC, GAP-43, PSD-95, synapsin, and synaptophysin. Indeed, reshaping of neuronal connectivity after the primary, acute epileptogenesis event increases the excitability of the temporal lobe. Herein, we also discussed the heterogeneity of neuronal populations regarding the number of synaptic connections, which in the theoretical field is commonly referred as degree. Employing integrate-and-fire neuronal model, we determined that in addition to increased synaptic strength, degree correlations might play essential and unsuspected roles in the control of network activity. Indeed, assortativity, which can be described as a condition where high-degree correlations are observed, increases the excitability of neural networks. In this review, we summarized recent topics in the field, and data were discussed according to newly developed or unusual tools, as provided by mathematical graph analysis and high-order statistics. With this, we were able to present new foundations for the pathological activity observed in temporal lobe epilepsy.

Aspectos epidemiológicos e distribuição anatômica das diferentes formas clínicas do sarcoide equino no Rio Grande do Sul: 40 casos / Epidemiological aspects and anatomic distribuition of equine sarcoid in the state of Rio Grande do Sul, Brazil: 40 cases

The files of histopathological exams carried out by the Laboratório de Patologia Veterinária of the Universidade Federal de Santa Maria (LPV-UFSM), between January 2000 and March 2010, were reviewed in search of cases of equine sarcoid. Forty cases were selected to determine epidemiological aspects and anatomical distribution of the various clinical forms of these neoplasms in horses from Rio Grande do Sul. Out of the cases in which the ages were registered in the histopathological reports, 73.0 percent (27/37) were 1 to 5-year-old horses. Multiple sarcoids were observed in most of the affected horses (29/40 [72.5 percent]). The fibroblastic form was most frequently observed and occurred in 42.2 percent (27/64) of the cases. In more than half of the cases (22/40 [55.0 percent]), sarcoids had a multifocal distribution. Twenty two (55 percent) out of the 40 horses evaluated had the tumors in the limbs.(AU)

Foram revisados todos os protocolos de exames histopatológicos, arquivados no Laboratório de Patologia Veterinária da Universidade Federal de Santa Maria (LPV-UFSM), realizados entre janeiro de 2000 e março de 2010, na busca de casos de sarcoide equino. Quarenta casos foram selecionados com o objetivo de determinar os aspectos epidemiológicos e a distribuição anatômica das diferentes formas clínicas deste tumor em equinos no Rio Grande do Sul. Dos casos que tiveram suas idades anotadas nos protocolos, 73,0 por cento (27/37) eram de equinos entre 1 e 5 anos de idade. Múltiplos sarcoides foram observados na maioria dos equinos afetados (29/40 [72,5 por cento]). A forma clínica mais observada foi a fibroblástica, que ocorreu em 42,2 por cento (27/64) dos casos. Em mais da metade dos casos (22/40 [55,0 por cento]), os sarcoides tinham distribuição multifocal. Equinos que apresentavam tumores nos membros totalizaram 22 dos 40 (55 por cento) casos analisados.(AU)

Quality of life and the self-perception impact of epilepsy in three different epilepsy types

PURPOSE: This study aimed to evaluate the quality of life (QOL) and verify the domains of greater impact in patients with focal and generalized epilepsies. METHODS: The sample, composed by 57 subjects from Hospital São Paulo da Universidade Federal de São Paulo, was divided into 3 groups, temporal lobe epilepsies (TLE), extra-temporal epilepsies (Extra-TLE) and idiopathic generalized epilepsy (IGE). They answered a preliminary self-reported questionnaire to identify the perception of the most impaired aspects in their lives. The QOL was evaluated through the validated Brazilian version of the Quality of Life Epilepsy Inventory 31 (QOLIE-31). The correlation of the QOLIE-31 domains with epilepsy duration and seizure frequency was defined by dispersion graphics and also Pearson’s and Spearman’s correlation. RESULTS: The most frequently identified impact of epilepsy was related to interpersonal, familial and social relationships mentioned by 13 (22.81 percent) patients. The seizure frequency per patient in Extra-TLE group was significantly greater (p = 0.007) than in the other groups. The Cognition Functioning scores were lower for the Extra-TLE group (38.4) when compared with TLE (52.6) and IGE (62.6) (p = 0.01). The correlation between epilepsy duration and QOLIE-31 domains did not demonstrate statistical significance; however, seizure frequency was correlated with Seizures Worry (p = 0.0463, alpha = 0.05) and Medication Effects (p = 0.0476, alpha = 0.05) domains. CONCLUSIONS: 1) Interpersonal, familial, and social relationships were the dimension which most impacted daily life; 2) Cognition domain in Extra-TLE group showed the worst scores; 3) QOL scores were similar in the three groups for the majority of the QOLIE-31 domains; 4) The seizure frequency in the Extra-TLE group was significantly greater; 5) Seizure frequency was associated with worse QOLIE-31 scores in the domains Seizure Worry and Medication Effects.

OBJETIVO: Este estudo teve como objetivo avaliar a qualidade de vida (QV) em três diferentes grupos de epilepsia e verificar a esfera percebida como de maior impacto na vida diária. METODOLOGIA: A amostra foi composta por 57 pacientes com epilepsias focais e generalizadas do Hospital São Paulo, Universidade Federal de São Paulo, divididos em três grupos, epilepsias do lobo temporal (ELT), extratemporais (Extra-ELT) e generalizadas idiopáticas (EGI). Os pacientes responderam a um questionário preliminar para identificar a percepção sobre os aspectos mais comprometidos em suas vidas. A QV foi avaliada por meio da versão brasileira do Quality of Life in Epilepsy Inventory 31 (QOLIE-31). A correlação dos domínios do QOLIE-31 com a duração da epilepsia e freqüência de crises foi definida pela inspeção dos gráficos de dispersão e pela correlação de Pearson e de Spearman. Foram considerados significantes os valores de p < 0,05. RESULTADOS: Dificuldades nas relações interpessoais, familiares e sociais foram apontadas como a esfera de maior impacto relacionado à epilepsia, citada por 13 (22,81 por cento) pacientes. O QOLIE-31 mostrou resultado semelhante nos três diferentes tipos de epilepsia, com exceção do domínio Funcionamento Cognitivo. Os escores deste domínio foram significativamente menores (p = 0,01) no grupo com Extra-ELT (38,4) do que nos grupos ELT (52,6) e EGI (62,6). A duração da epilepsia não influenciou na QOL nesta amostra, porém foi observada uma correlação estatística significante entre a freqüência de crises e os domínios Efeitos da Medicação (p = 0,0476, alfa = 0,05) e Preocupação com Crises (p = 0,0463, alfa = 0,05). A freqüência de crises mostrou ainda uma diferença estatisticamente significante (p = 0.007) no grupo com Extra-ELT, que apresentou mais crises/paciente, quando comparado aos demais grupos. CONCLUSÕES: Os pacientes identificaram as relações interpessoais, familiares e sociais como sendo a área mais afetada pela...