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1.
J Oncol Pharm Pract ; 30(2): 257-262, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37151079

RESUMO

Pharmacy personnel that manipulate cytotoxic drugs are under continuous exposure risk. Therefore, training and strict adherence to recommended practices should always be promoted. The main objective of this study was to develop and apply a safe, effective and low-cost method for the training and assessment of the safe handling of cytotoxic drugs, using commercially available tonic water. To evaluate the potential of tonic water as a replacement marker for quinine hydrochloride, deliberate spills of 1 mL of four different tonic waters (one coloured and three non-coloured) were analysed under ultraviolet light (300-400 nm). The pigmented sample did not produce fluorescence under ultraviolet (UV) light. The three commercially available tonic waters that exhibited fluorescence were further analysed by UV/Vis spectrophotometry (300-500 nm). Afterwards, a protocol of simulated manipulation of cytotoxic drugs was developed and applied to 12 pharmacy technicians, that prepared 24 intravenous bags according to recommended routine procedures using tonic water. Participants responded to a brief questionnaire to evaluate the adequacy and applicability of the activity. Seven of the participants had spillages during manipulation, the majority of which recorded during manipulation with needles. All participants scored the tonic water manipulation simulation with 4 or 5 points for simplicity, efficiency and feasibility. The obtained results suggest that tonic water can be used to simulate the manipulation of cytotoxic drugs in training and assessment programs. By using this replacement marker for quinine hydrochloride, it is possible to perform a more cost-effective, yet equally effective, assessment.


Assuntos
Antineoplásicos , Exposição Ocupacional , Farmácia , Humanos , Quinina/análise , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/análise , Antineoplásicos/uso terapêutico , Água/análise
2.
Epilepsia ; 64(11): 2891-2908, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37676719

RESUMO

Despite progress in the development of anti-seizure medications (ASMs), one third of people with epilepsy have drug-resistant epilepsy (DRE). The working definition of DRE, proposed by the International League Against Epilepsy (ILAE) in 2010, helped identify individuals who might benefit from presurgical evaluation early on. As the incidence of DRE remains high, the TASK1 workgroup on DRE of the ILAE/American Epilepsy Society (AES) Joint Translational Task Force discussed the heterogeneity and complexity of its presentation and mechanisms, the confounders in drawing mechanistic insights when testing treatment responses, and barriers in modeling DRE across the lifespan and translating across species. We propose that it is necessary to revisit the current definition of DRE, in order to transform the preclinical and clinical research of mechanisms and biomarkers, to identify novel, effective, precise, pharmacologic treatments, allowing for earlier recognition of drug resistance and individualized therapies.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Humanos , Estados Unidos , Epilepsia/tratamento farmacológico , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Resistência a Medicamentos , Comitês Consultivos , Incidência
3.
Nitric Oxide ; 129: 82-101, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36280191

RESUMO

The systemic cardiovascular effects of major trauma, especially neurotrauma, contribute to death and permanent disability in trauma patients and treatments are needed to improve outcomes. In some trauma patients, dysfunction of the autonomic nervous system produces a state of adrenergic overstimulation, causing either a sustained elevation in catecholamines (sympathetic storm) or oscillating bursts of paroxysmal sympathetic hyperactivity. Trauma can also activate innate immune responses that release cytokines and damage-associated molecular patterns into the circulation. This combination of altered autonomic nervous system function and widespread systemic inflammation produces secondary cardiovascular injury, including hypertension, damage to cardiac tissue, vascular endothelial dysfunction, coagulopathy and multiorgan failure. The gasotransmitters nitric oxide (NO) and hydrogen sulfide (H2S) are small gaseous molecules with potent effects on vascular tone regulation. Exogenous NO (inhaled) has potential therapeutic benefit in cardio-cerebrovascular diseases, but limited data suggests potential efficacy in traumatic brain injury (TBI). H2S is a modulator of NO signaling and autonomic nervous system function that has also been used as a drug for cardio-cerebrovascular diseases. The inhaled gases NO and H2S are potential treatments to restore cardio-cerebrovascular function in the post-trauma period.


Assuntos
Doenças Cardiovasculares , Sistema Cardiovascular , Gasotransmissores , Sulfeto de Hidrogênio , Humanos , Sulfeto de Hidrogênio/uso terapêutico , Sulfeto de Hidrogênio/farmacologia , Óxido Nítrico , Gasotransmissores/uso terapêutico
4.
Metab Brain Dis ; 37(6): 1863-1874, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35759072

RESUMO

Hydrogen sulfide (H2S) is a gasotransmitter endogenously synthesized by cystathionine-γ-lyase (CSE), cystathionine-ß-synthase (CBS), and 3-mercaptopiruvate sulfurtransferase (3-MST) enzymes. H2S exogenous administration prevents the development of hemodynamic impairments after traumatic brain injury (TBI). Since the hypothalamus and the brainstem highly regulate the cardiovascular system, this study aimed to evaluate the effect of NaHS subchronic treatment on the changes of H2S-sythesizing enzymes in those brain areas after TBI and in physiological conditions. For that purpose, animals were submitted to a lateral fluid percussion injury, and the changes in CBS, CSE, and 3-MST protein expression were measured by western blot at days 1, 2, 3, 7, and 28 in the vehicle group, and 7 and 28 days after NaHS treatment. After severe TBI induction, we found a decrease in CBS and CSE protein expression in the hypothalamus and brainstem; meanwhile, 3-MST protein expression diminished only in the hypothalamus compared to the Sham group. Remarkably, i.p. daily injections of NaHS, an H2S donor, (3.1 mg/kg) during seven days: (1) restored CBS and CSE but no 3-MST protein expression in the hypothalamus at day 28 post-TBI; (2) reestablished only CSE in brainstem 7 and 28 days after TBI; and (3) did not modify H2S-sythesizing enzymes protein expression in uninjured animals. Mainly, our results show that the NaHS effect on CBS and CSE protein expression is observed in a time- and tissue-dependent manner with no effect on 3-MST expression, which may suggest a potential role of H2S synthesis in hypothalamus and brainstem impairments observed after TBI.


Assuntos
Lesões Encefálicas Traumáticas , Sulfeto de Hidrogênio , Animais , Lesões Encefálicas Traumáticas/tratamento farmacológico , Tronco Encefálico , Cistationina , Cistationina beta-Sintase/metabolismo , Sulfeto de Hidrogênio/farmacologia , Hipotálamo/metabolismo
5.
Gac Med Mex ; 158(3): 157-159, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35894750

RESUMO

Due to sanitary restrictions secondary to the COVID-19 pandemic, various interactions between the pharmaceutical industry and physicians have changed. One of them has been the method for promoting medicinal products through academic meetings around diseases of financial interest. A recent modality has been unilateral promotion by the pharmaceutical industry through academic events with the invitation of so-called "experts" for the promotion of a specific drug. These meetings are often biased not towards optimal care of a disease, but rather towards commercial promotion of a specific drug, which may or may not be the best option, without considering associated therapeutic alternatives. The Committee of Ethics and Transparency in the Physician-Industry Relationship, of the National Academy of Medicine, analyzes this new circumstance and proposes some considerations to the medical community.


Debido a las restricciones sanitarias secundarias a la pandemia de COVID-19, diversas interacciones entre la industria farmacéutica y los médicos cambiaron. Una de ellas ha sido el método promocional de medicamentos a través de reuniones académicas en torno a padecimientos de interés financiero. Una modalidad reciente ha sido la promoción unilateral de un fármaco determinado por parte de la industria farmacéutica por medio de eventos académicos con la invitación de aparentes "expertos". Estas reuniones frecuentemente están sesgadas no hacia la atención óptima de un padecimiento, sino a la promoción comercial de un medicamento específico que pudiera o no ser la mejor opción o sin la consideración de alternativas terapéuticas asociadas. El Comité de Ética y Transparencia en la Relación Médico-Industria, de la Academia Nacional de Medicina de México, analiza esta nueva circunstancia y propone algunas consideraciones a la comunidad médica.


Assuntos
COVID-19 , Medicina , Médicos , Indústria Farmacêutica , Humanos , Pandemias
6.
Epilepsy Behav ; 121(Pt B): 106430, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-31378558

RESUMO

Drug-resistant epilepsy affects approximately one-third of the patients with epilepsy. The pharmacoresistant condition in epilepsy is mainly explained by six hypotheses. In addition, several experimental models have been used to understand the mechanisms involved in pharmacoresistant epilepsy and to identify novel therapies to control this condition. However, the global prevalence of this disease persists without changes. Several factors can explain this situation. First of all, the pharmacoresistant epilepsy is explained by different and independent hypotheses. Each hypothesis indicates specific mechanisms to explain the drug-resistant condition in epilepsy. However, there are different findings suggesting common mechanisms between the different hypotheses. Other important situation is that the experimental models designed for the screening of drugs with potential anticonvulsant effect do not consider factors such as age, gender, type of epilepsy, and comorbid disorders. The present review focuses on indicating the limitations for each hypothesis and the relationships among them. The relevance to consider central and peripheral phenomena associated with the drug-resistant condition in different types of epilepsy is also indicated. The necessity to establish a global hypothesis that integrates all the phenomena associated with the pharmacoresistant epilepsy is proposed. This article is part of the Special Issue "NEWroscience 2018".


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Preparações Farmacêuticas , Anticonvulsivantes/uso terapêutico , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Epilepsia/tratamento farmacológico , Humanos
7.
Epilepsy Behav ; 115: 107659, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33334719

RESUMO

Transcranial focal stimulation (TFS) is a noninvasive neuromodulation strategy that reduces seizure activity in different experimental models. Nevertheless, there is no information about the effects of TFS in the drug-resistant phenotype associated with P-glycoprotein (Pgp) overexpression. The present study focused on determining the effects of TFS on Pgp expression after an acute seizure induced by 3-mercaptopropionic acid (MPA). P-glycoprotein expression was analyzed by western blot in the cerebral cortex and hippocampus of rats receiving 5 min of TFS (300 Hz, 50 mA, 200 µs, biphasic charge-balanced squared pulses) using a tripolar concentric ring electrode (TCRE) prior to administration of a single dose of MPA. An acute administration of MPA induced Pgp overexpression in cortex (68 ±â€¯13.4%, p < 0.05 vs the control group) and hippocampus (48.5 ±â€¯14%, p < 0.05, vs the control group). This effect was avoided when TFS was applied prior to MPA. We also investigated if TFS augments the effects of phenytoin in an experimental model of drug-resistant seizures induced by repetitive MPA administration. Animals with MPA-induced drug-resistant seizures received TFS alone or associated with phenytoin (75 mg/kg, i.p.). TFS alone did not modify the expression of the drug-resistant seizures. However, TFS combined with phenytoin reduced seizure intensity, an effect associated with a lower prevalence of major seizures (50%, p = 0.03 vs phenytoin alone). Our experiments demonstrated that TFS avoids the Pgp overexpression induced after an acute convulsive seizure. In addition, TFS augments the phenytoin effects in an experimental model of drug-resistant seizures. According with these results, it is indicated that TFS may represent a new neuromodulatory strategy to revert the drug-resistant phenotype.


Assuntos
Hipocampo , Convulsões , Subfamília B de Transportador de Cassetes de Ligação de ATP , Animais , Modelos Animais de Doenças , Eletrodos , Ratos , Convulsões/induzido quimicamente
8.
Epilepsy Behav ; 121(Pt B): 106451, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-31420290

RESUMO

Despite the approval of a considerable number of last generation antiepileptic drugs (AEDs) (only in the last decade, six drugs have gained Food and Drug Administration approval), the global figures of seizure control have seemingly not improved, and available AED can still be regarded as symptomatic treatments. Fresh thinking in AEDs drug discovery, including the development of drugs with novel mechanisms of action, is required to achieve truly innovative antiepileptic medications. The transporter hypothesis proposes that inadequate penetration of AEDs across the blood-brain barrier, caused by increased expression of efflux transporters such as P-glycoprotein (P-gp), contributes to drug-resistant epilepsy. Neuroinflammation due to high levels of glutamate has been identified as one of the causes of P-gp upregulation, and several studies in animal models of epilepsy suggest that antiinflammatory drugs might prevent P-gp overexpression and, thus, avoid the development of refractory epilepsy. We have applied ligand-based in silico screening to select compounds that exert dual anticonvulsant and antiinflammatory effects. Five of the hits were tested in animal models of seizure, with protective effects. Later, two of them (sebacic acid (SA) and gamma-decanolactone) were submitted to the recently described MP23 model of drug-resistant seizures. All in all, SA displayed the best profile, showing activity in the maximal electroshock seizure (MES) and pentylenetetrazol (PTZ) seizure models, and reversing resistance to phenytoin (PHT) and decreasing the P-gp upregulation in the MP23 model. Furthermore, pretreatment with SA in the pilocarpine status epilepticus (SE) model resulted in decreased histamine release in comparison with nontreated animals. This is the first report of the use of the MP23 model to screen for novel anticonvulsant compounds that may avoid the development of P-gp-related drug resistance.


Assuntos
Anticonvulsivantes , Preparações Farmacêuticas , Subfamília B de Transportador de Cassetes de Ligação de ATP/uso terapêutico , Animais , Anticonvulsivantes/uso terapêutico , Modelos Animais de Doenças , Camundongos , Convulsões/tratamento farmacológico
9.
An Acad Bras Cienc ; 93(2): e20190861, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729379

RESUMO

Autism spectrum disorder is associated with alterations in GABAergic and glutamatergic neurotransmission. Here, we aimed to determine the concentration of GABA, glutamate, glutamine, aspartate, taurine, and glycine in brain tissue and plasma of rats prenatally exposed to valproic acid (VPA), a well-characterized experimental model of autism. Pregnant rats were injected with VPA (600mg/Kg) during the twelfth-embryonic-day. Control rats were injected with saline. On the fourteen-postnatal-day, rats from both groups (males and females) were anesthetized, euthanized by decapitation and their brain dissected out. The frontal cortex, hippocampus, amygdala, brain stem and cerebellum were dissected and homogenized. Homogenates were centrifuged and supernatants were used to quantify amino acid concentrations by HPLC coupled with fluorometric detection. Blood samples were obtained by a cardiac puncture; plasma was separated and deproteinized to quantify amino acid concentration by HPLC. We found that, in VPA rats, glutamate and glutamine concentrations were increased in hippocampus and glycine concentration was increased in cortex. We did not find changes in other regions or in plasma amino acid concentration in the VPA group with respect to control group. Our results suggest that VPA exposure in utero may impair inhibitory and excitatory amino acid transmission in the infant brain.


Assuntos
Transtorno do Espectro Autista , Efeitos Tardios da Exposição Pré-Natal , Aminoácidos , Animais , Encéfalo , Feminino , Masculino , Plasma , Gravidez , Ratos , Ácido Valproico/toxicidade
10.
Microvasc Res ; 132: 104059, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32798551

RESUMO

The blood-brain barrier (BBB) maintains the optimal microenvironment for brain function. Tight junctions (TJs) allow endothelial cells to adhere to each other, leading to the formation of a barrier that prevents the penetration of most molecules via transcellular routes. Evidence has indicated that seizure-induced vascular endothelial growth factor (VEGF) type 2 receptor (VEGFR-2) pathway activation weakens TJs, inducing vasodilatation and increasing vascular permeability and subsequent brain injury. The present study focused on investigating the expression levels of VEGF-related (VEGF-A and VEGFR-2) and TJ-related proteins (claudin-5, occludin and ZO-1) in the neocortical microvasculature of patients with drug-resistant temporal lobe epilepsy (TLE). The results obtained from hippocampal sclerosis TLE (HS-TLE) patients were compared with those obtained from patients with TLE secondary to lesions (lesion-TLE) and autopsy samples. The Western blotting and immunofluorescence results showed that VEGF-A and VEGFR-2 protein expression levels were increased in HS-TLE and lesion-TLE patients compared to autopsy group. On the other hand, claudin-5 expression was higher in HS-TLE patients and lesion-TLE patients than autopsies. The expression level of occludin and ZO-1 was decreased in HS-TLE patients. Our study described modifications to the integrity of the BBB that may contribute to the pathogenesis of TLE, in which the VEGF system may play an important role. We demonstrated that the same modifications were present in both HS-TLE and lesion-TLE patients, which suggests that seizures modify these systems and that they are not associated with the establishment of epilepsy.


Assuntos
Barreira Hematoencefálica/metabolismo , Epilepsia Resistente a Medicamentos/metabolismo , Epilepsia do Lobo Temporal/metabolismo , Microvasos/metabolismo , Neocórtex/irrigação sanguínea , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adolescente , Adulto , Barreira Hematoencefálica/patologia , Claudina-5/metabolismo , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Epilepsia Resistente a Medicamentos/patologia , Epilepsia do Lobo Temporal/tratamento farmacológico , Epilepsia do Lobo Temporal/patologia , Feminino , Humanos , Masculino , Microvasos/patologia , Pessoa de Meia-Idade , Ocludina/metabolismo , Transdução de Sinais , Junções Íntimas/patologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Adulto Jovem , Proteína da Zônula de Oclusão-1/metabolismo
11.
Int J Mol Sci ; 21(9)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32366006

RESUMO

Benzodiazepines (BZDs) are widely used in patients of all ages. Unlike adults, neonatal animals treated with BZDs exhibit a variety of behavioral deficits later in life; however, the mechanisms underlying these deficits are poorly understood. This study aims to examine whether administration of clonazepam (CZP; 1 mg/kg/day) in 7-11-day-old rats affects Gama aminobutyric acid (GABA)ergic receptors in both the short and long terms. Using RT-PCR and quantitative autoradiography, we examined the expression of the selected GABAA receptor subunits (α1, α2, α4, γ2, and δ) and the GABAB B2 subunit, and GABAA, benzodiazepine, and GABAB receptor binding 48 h, 1 week, and 2 months after treatment discontinuation. Within one week after CZP cessation, the expression of the α2 subunit was upregulated, whereas that of the δ subunit was downregulated in both the hippocampus and cortex. In the hippocampus, the α4 subunit was downregulated after the 2-month interval. Changes in receptor binding were highly dependent on the receptor type, the interval after treatment cessation, and the brain structure. GABAA receptor binding was increased in almost all of the brain structures after the 48-h interval. BZD-binding was decreased in many brain structures involved in the neuronal networks associated with emotional behavior, anxiety, and cognitive functions after the 2-month interval. Binding of the GABAB receptors changed depending on the interval and brain structure. Overall, the described changes may affect both synaptic development and functioning and may potentially cause behavioral impairment.


Assuntos
Clonazepam/farmacologia , Receptores de GABA-A/metabolismo , Receptores de GABA-B/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Animais Recém-Nascidos , Benzodiazepinas/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Ligação Proteica , Ratos , Ratos Endogâmicos WF , Reação em Cadeia da Polimerase em Tempo Real
13.
Epilepsy Behav ; 94: 118-123, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30903955

RESUMO

The Repressor Element-1 Silencing Transcription factor or Neuron-Restrictive Silencer Factor (REST/NRSF) is a zinc finger repressor transcription factor of the Kruppel family. Several studies in experimental models have shown that overexpression of REST/NRSF occurs after the induction of seizures. In the present study, the expression of REST/NRSF (messenger ribonucleic acid (mRNA) and protein) was evaluated in the hippocampus of 28 patients with drug-resistant mesial temporal lobe epilepsy (MTLE) and their correlation with clinical variables and comorbid anxiety and depression. The REST/NRSF protein expression was augmented in an age-dependent manner in the hippocampus of autopsied subjects. However, this condition was not observed in patients with MTLE, in whom overexpression of this transcription factor occurred at both the mRNA and protein levels. The correlations with clinical variables showed that the frequency of epileptic seizures was proportional to the protein expression of REST/NRSF. The results revealed that the overexpression of REST/NRSF was more evident in patients with MTLE without anxiety and depression. Our data indicate that the expression of REST/NRSF is modified in patients with MTLE. This condition has implications in the pathophysiology of this disorder, making it a potential candidate for the optimization of clinical treatments.


Assuntos
Epilepsia Resistente a Medicamentos/metabolismo , Epilepsia do Lobo Temporal/metabolismo , Hipocampo/metabolismo , Neurônios/metabolismo , Proteínas Repressoras/metabolismo , Adolescente , Adulto , Ansiedade/complicações , Ansiedade/genética , Ansiedade/metabolismo , Depressão/complicações , Depressão/genética , Depressão/metabolismo , Epilepsia Resistente a Medicamentos/complicações , Epilepsia Resistente a Medicamentos/genética , Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/genética , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Repressoras/genética , Adulto Jovem
14.
Epilepsy Behav ; 87: 200-206, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30115604

RESUMO

Several studies indicate that sodium cromoglycate (CG) induces neuroprotective effects in acute neurological conditions. The present study focused on investigating if the use of CG in rats during the post-status epilepticus (post-SE) period reduces the acute and long-term consequences of seizure activity. Our results revealed that animals that received a single dose of CG (50 mg/kg s.c.: subcutaneously) during the post-SE period showed a lower number of neurons in the process of dying in the dentate gyrus, hilus, cornu ammonis 1 (CA1), and CA3 of the dorsal hippocampus than the rats that received the vehicle. However, this effect was not evident in layers V-VI of the sensorimotor cortex or the lateral-posterior thalamic nucleus. A second experiment showed that animals that received CG subchronically (50 mg/kg s.c. every 12 h for 5 days followed by 24 mg/kg/day s.c. for 14 days using osmotic minipumps) after SE presented fewer generalized convulsive seizures and less neuronal damage in the lateral-posterior thalamic nucleus but not in the hippocampus or cortex. Our data indicate that CG can be used as a therapeutic strategy to reduce short- and long-term neuronal damage in the hippocampus and thalamus, respectively. The data also indicate that CG can reduce the expression of generalized convulsive spontaneous seizures when it is given during the latent period of epileptogenesis.


Assuntos
Cromolina Sódica/uso terapêutico , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/patologia , Animais , Cromolina Sódica/farmacologia , Giro Denteado/efeitos dos fármacos , Giro Denteado/patologia , Giro Denteado/fisiopatologia , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Hipocampo/fisiopatologia , Masculino , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ratos , Ratos Wistar , Estado Epiléptico/fisiopatologia , Fatores de Tempo
15.
Epilepsy Behav ; 88: 283-294, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30336420

RESUMO

Synaptic vesicle protein 2A (SV2A) has become an attractive target of investigation because of its role in the pathophysiology of epilepsy; SV2A is expressed ubiquitously throughout the brain in all nerve terminals independently of their neurotransmitter content and plays an important but poorly defined role in neurotransmission. Previous studies have shown that modifications in the SV2A protein expression could be a direct consequence of disease severity. Furthermore, these SV2A modifications may depend on specific changes in the nerve tissue following the induction of epilepsy and might be present in both excitatory and inhibitory terminals. Thus, we evaluated SV2A protein expression throughout the hippocampi of lithium-pilocarpine rats after status epilepticus (SE) and during early and late epilepsy. In addition, we determined the γ-aminobutyric acid (GABA)ergic or glutamatergic nature associated with SV2A modifications. Wistar rats were treated with lithium-pilocarpine to induce SE and subsequently were shown to present spontaneous recurrent seizures (SRS). Later, we conducted an exhaustive semi-quantitative analysis of SV2A optical density (OD) throughout the hippocampus by immunohistochemistry. Levels of the SV2A protein were substantially increased in layers formed by principal neurons after SE, mainly because of GABAergic activity. No changes were observed in the early stage of epilepsy. In the late stage of epilepsy, there were minor changes in SV2A OD compared with the robust modifications of SE; however, SV2A protein expression generally showed an increment reaching significant differences in two dendritic layers and hilus, without clear modifications of GABAergic or glutamatergic systems. Our results suggest that the SV2A variations may depend on several factors, such as neuronal activity, and might appear in both excitatory and inhibitory systems depending on the epilepsy stage.


Assuntos
Hipocampo/metabolismo , Cloreto de Lítio/toxicidade , Glicoproteínas de Membrana/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Pilocarpina/toxicidade , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/metabolismo , Animais , Modelos Animais de Doenças , Expressão Gênica , Hipocampo/efeitos dos fármacos , Masculino , Glicoproteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Ratos Wistar , Estado Epiléptico/genética
16.
Epilepsia ; 57(4): e76-80, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26915454

RESUMO

Experiments were designed to evaluate the tissue content of tele-methylhistamine (t-MeHA) and histamine as well as H3 receptor (H3 Rs) binding and activation of the heterotrimeric guanine nucleotide binding αi/o proteins (Gαi/o) coupled to these receptors in the hippocampus and temporal neocortex of patients (n = 10) with pharmacoresistant mesial temporal lobe epilepsy (MTLE). Patients with MTLE showed elevated tissue content of t-MeHA in the hippocampus. Analyses revealed that a younger age at seizure onset was correlated with a higher tissue content of t-MeHA, lower H3 R binding, and lower efficacy of Gαi/o protein activation in the hippocampus. We conclude that the hippocampus shows a reduction in the H3 R function associated with enhanced histamine. In contrast, the temporal neocortex displayed a high efficacy of H3 Rs Gαi/o protein activation that was associated with low tissue contents of histamine and t-MeHA. These results indicate an overactivation of H3 Rs leading to decreased histamine in the temporal neocortex. However, this situation was lessened in circumstances such as a longer duration of epilepsy or higher seizure frequency. It is concluded that decrease in H3 Rs function and enhanced levels of histamine may contribute to the epileptic activity in the hippocampus and temporal neocortex of patients with pharmacoresistant MTLE.


Assuntos
Epilepsia Resistente a Medicamentos/metabolismo , Epilepsia do Lobo Temporal/metabolismo , Hipocampo/metabolismo , Histamina/metabolismo , Receptores Histamínicos H3/metabolismo , Lobo Temporal/metabolismo , Adulto , Epilepsia Resistente a Medicamentos/patologia , Epilepsia do Lobo Temporal/patologia , Feminino , Hipocampo/patologia , Humanos , Masculino , Neocórtex/metabolismo , Lobo Temporal/patologia , Adulto Jovem
17.
J Neurochem ; 132(2): 206-17, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25330347

RESUMO

Physical exercise stimulates the release of endogenous opioid peptides supposed to be responsible for changes in mood, anxiety, and performance. Exercise alters sensitivity to these effects that modify the efficacy at the opioid receptor. Although there is evidence that relates exercise to neuropeptide expression in the brain, the effects of exercise on opioid receptor binding and signal transduction mechanisms downstream of these receptors have not been explored. Here, we characterized the binding and G protein activation of mu opioid receptor, kappa opioid receptor or delta opioid receptor in several brain regions following acute (7 days) and chronic (30 days) exercise. As regards short- (acute) or long-term effects (chronic) of exercise, overall, higher opioid receptor binding was observed in acute-exercise animals and the opposite was found in the chronic-exercise animals. The binding of [(35) S]GTPγS under basal conditions (absence of agonists) was elevated in sensorimotor cortex and hippocampus, an effect more evident after chronic exercise. Divergence of findings was observed for mu opioid receptor, kappa opioid receptor, and delta opioid receptor receptor activation in our study. Our results support existing evidence of opioid receptor binding and G protein activation occurring differentially in brain regions in response to diverse exercise stimuli. We characterized the binding and G protein activation of mu, kappa, and delta opioid receptors in several brain regions following acute (7 days) and chronic (30 days) exercise. Higher opioid receptor binding was observed in the acute exercise animal group and opposite findings in the chronic exercise group. Higher G protein activation under basal conditions was noted in rats submitted to chronic exercise, as visible in the depicted pseudo-color autoradiograms.


Assuntos
Química Encefálica , Condicionamento Físico Animal , Receptores Opioides/metabolismo , Tonsila do Cerebelo/metabolismo , Animais , Benzenoacetamidas/metabolismo , Córtex Cerebral/metabolismo , Eletrochoque , D-Penicilina (2,5)-Encefalina/metabolismo , Ativação Enzimática , Proteínas de Ligação ao GTP/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Hipocampo/metabolismo , Hipotálamo/metabolismo , Naloxona/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Peptídeos Opioides/metabolismo , Ligação Proteica , Pirrolidinas/metabolismo , Ratos , Transdução de Sinais , Fatores de Tempo
18.
Epilepsy Behav ; 49: 33-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26006058

RESUMO

The aim of the present study was to evaluate the effects of transcranial focal electrical stimulation (TFS) on γ-aminobutyric acid (GABA) and glutamate release in the hippocampus under basal conditions and during pilocarpine-induced status epilepticus (SE). Animals were previously implanted with a guide cannula attached to a bipolar electrode into the right ventral hippocampus and a concentric ring electrode placed on the skull surface. The first microdialysis experiment was designed to determine, under basal conditions, the effects of TFS (300 Hz, 200 µs biphasic square pulses, for 30 min) on afterdischarge threshold (ADT) and the release of GABA and glutamate in the hippocampus. The results obtained indicate that at low current intensities (<2800 µA), TFS enhances and decreases the basal extracellular levels of GABA and glutamate, respectively. However, TFS did not modify the ADT. During the second microdialysis experiment, a group of animals was subjected to SE induced by pilocarpine administration (300 mg/kg, i.p.; SE group). The SE was associated with a significant rise of GABA and glutamate release (up to 120 and 182% respectively, 5h after pilocarpine injection) and the prevalence of high-voltage rhythmic spikes and increased spectral potency of delta, gamma, and theta bands. A group of animals (SE-TFS group) received TFS continuously during 2h at 100 µA, 5 min after the establishment of SE. This group showed a significant decrease in the expression of the convulsive activity and spectral potency in gamma and theta bands. The extracellular levels of GABA and glutamate in the hippocampus remained at basal conditions. These results suggest that TFS induces anticonvulsant effects when applied during the SE, an effect associated with lower amino acid release. This article is part of a Special Issue entitled "Status Epilepticus".


Assuntos
Ácido Glutâmico/metabolismo , Hipocampo/metabolismo , Estado Epiléptico/terapia , Estimulação Transcraniana por Corrente Contínua , Ácido gama-Aminobutírico/metabolismo , Animais , Modelos Animais de Doenças , Masculino , Pilocarpina , Ratos , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/metabolismo
19.
Epilepsy Behav ; 38: 25-31, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24472685

RESUMO

It is well known that mood disorders are highly prevalent in patients with epilepsy. Although several studies have aimed to characterize alterations in different types of receptors associated with both disturbances, there is a lack of studies focused on identifying the causes of this comorbidity. Here, we described some changes at the biochemical level involving serotonin, dopamine, and γ-aminobutyric acid (GABA) receptors as well as signal transduction mechanisms that may explain the coexistence of both epilepsy and mood disorders. Finally, the identification of common pathophysiological mechanisms associated with receptor-receptor interaction (heterodimers) could allow designing new strategies for treatment of patients with epilepsy and comorbid mood disorders.


Assuntos
Comorbidade , Epilepsia/metabolismo , Transtornos do Humor/metabolismo , Transdução de Sinais/fisiologia , Epilepsia/epidemiologia , Humanos , Transtornos do Humor/epidemiologia
20.
Arch Med Res ; 55(3): 102985, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38520880

RESUMO

BACKGROUND: Toll-like receptors (TLRs) play a critical role in initiating the innate immune response to infection or injury. Recent studies have uncovered their intriguing functions as moonlighting proteins involved in various biological processes, including development, learning, and memory. However, the specific functions of individual TLRs are still largely unknown. AIMS: We investigated the effects of TLR3 and TLR9 receptor deficiency on motor, cognitive, and behavioral functions during development using genetically modified male mice of different ages. METHODS: We evaluated the motor coordination, anxiety-like behavior, spatial learning, and working memory of male mice lacking the TLR3 and TLR9 genes at different ages (two, four, six, and eight months) using the rotarod, open field, water maze, and T-maze tests. RESULTS: We observed that the deletion of either TLR3 or TLR9 resulted in impaired motor performance. Furthermore, young TLR3-deficient mice exhibited reduced anxiety-like behavior and spatial learning deficits; however, their working memory was unaffected. In contrast, young TLR9-knockout mice showed hyperactivity and a tendency toward decreased working memory. CONCLUSIONS: These findings provide valuable insights into the broader roles of the TLR system beyond the innate immune response, revealing its involvement in pathways associated with the central nervous system. Importantly, our results establish a strong association between the endosomal receptors TLR3 and TLR9 and the performance of motor, cognitive, and behavioral tasks that change over time. This study contributes to the growing body of research on the multifaceted functions of TLRs and enhances our understanding of their participation in non-immune-related processes.


Assuntos
Receptor 3 Toll-Like , Receptor Toll-Like 9 , Animais , Masculino , Camundongos , Cognição , Camundongos Knockout , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo , Receptor Toll-Like 9/genética , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
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