RESUMEN
Kruppel-like factor 4 (Klf4) is a transcription factor that is involved in neuronal regeneration and the development of glutamatergic systems. However, it is unknown whether Klf4 is involved in acute seizure. To investigate the potential role of Klf4 in pentylenetetrazol (PTZ)-induced seizure, western blotting, immunofluorescence, behaviour test and electrophysiology were conducted in this study. We found that Klf4 protein and mRNA expression were increased in both the hippocampus (HP) and prefrontal cortex (PFC) after PTZ-induced seizure in mice. HP-specific knockout (KO) of Klf4 in mice decreased protein expression of Klf4 and the down-stream Klf4 target tumour protein 53 (TP53/P53). These molecular changes are accompanied by increased seizure latency, reduced immobility time in the forced swimming test and tail suspension test. Reduced hippocampal protein levels for synaptic proteins, including glutamate receptor 1 (GRIA1/GLUA1) and postsynaptic density protein 95 (DLG4/PSD95), were also observed after Klf4-KO, while increased mRNA levels of complement proteins were observed for complement component 1q subcomponent A (C1qa), complement component 1q subcomponent B (C1qb), complement component 1q subcomponent C (C1qc), complement component 3 (C3), complement component 4A (C4a) and complement component 4B (C4b). Moreover, c-Fos expression induced by PTZ was reduced by hippocampal conditional KO of Klf4. Electrophysiology showed that PTZ-induced action potential frequency was decreased by overexpression of Klf4. In conclusion, these findings suggest that Klf4 plays an important role in regulating PTZ-induced seizures and therefore constitutes a new molecular target that should be explored for the development of antiepileptic drugs.
Asunto(s)
Hipocampo , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel , Ratones Noqueados , Pentilenotetrazol , Convulsiones , Animales , Factor 4 Similar a Kruppel/metabolismo , Convulsiones/metabolismo , Convulsiones/inducido químicamente , Convulsiones/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Factores de Transcripción de Tipo Kruppel/genética , Ratones , Hipocampo/metabolismo , Masculino , Corteza Prefrontal/metabolismo , Ratones Endogámicos C57BL , Modelos Animales de EnfermedadRESUMEN
BACKGROUND: Epilepsy is a paroxysmal abnormal hypersynchronous electrical discharge characterized by recurrent seizures. It affects more than 50 million people worldwide. Stress is the leading cause of neurodegeneration and can produce seizures that may lead to or aggravate epilepsy. Inflammation plays a vital role in epilepsy by modulating oxidative stress, and levels of neuroinflammatory cytokines including NF-κB, TNF-α, and IL-1ß. METHODS: Stress-induced changes in behavior were evaluated in mice by employing behavioral assessment tests such as an elevated plus maze, light-dark box, open field test, tail suspension test, Y-maze, novel object recognition test, and Morris water maze in pentylenetetrazole (PTZ) kindled mice. Behavioral changes in all these paradigms including seizure score, latency, and frequency showed an increase in symptoms in PTZ (35 mg/kg) induced seizures in stressed mice (RS-PTZ) as compared to PTZ, Stress, and normal animals. RESULTS: The Enzyme-linked immunosorbent assay (ELISA) results confirmed increased in serum cortisol levels. Histological examinations showed neurodegenerative changes in the hippocampus and cortex regions. The spectrophotometric evaluation showed an increase in oxidative stress by decreasing antioxidant production i.e. reduced glutathione, glutathione -s- transferase, and catalase (CAT), and increasing oxidant levels such as maloaldehyde and nitric oxide. Immunohistochemistry results showed increased expression of NF-κB, TNF-α, and IL-1ß in the cortex and hippocampus of mice brains. CONCLUSIONS: Results from the study conclude that stress increases the likelihood of eliciting an epileptic attack by increasing the level of reactive oxygen species and neuroinflammation.
Asunto(s)
Enfermedades Neuroinflamatorias , Estrés Oxidativo , Pentilenotetrazol , Convulsiones , Animales , Ratones , Convulsiones/metabolismo , Convulsiones/inducido químicamente , Convulsiones/patología , Masculino , Enfermedades Neuroinflamatorias/metabolismo , Enfermedades Neuroinflamatorias/etiología , Enfermedades Neuroinflamatorias/patología , Estrés Psicológico/complicaciones , Estrés Psicológico/metabolismo , Hipocampo/metabolismo , Hipocampo/patología , Enfermedad Crónica , Conducta AnimalRESUMEN
BACKGROUND: Status epilepticus is a common and potentially life-threatening neurological emergency with a high risk for cognitive and neurobiological impairment. Our aim was to evaluate the neuroprotective effects of centrally administered irisin and acute exhausting exercise against oxidative brain injury and memory dysfunction due to a pentylenetetrazole (PTZ)-induced single seizure. Male Sprague Dawley rats with intracerebroventricular (icv) cannulas were randomly divided into intraperitoneally (ip) saline-injected control and PTZ-injected (45 mg/kg) seizure groups. Both the control and PTZ groups were then treated with irisin (7.5 µg/kg, 2 µl, icv), saline (2 µl, icv) or were forced to an acute bout of strenuous exercise before the ip injection of saline (control) or PTZ. Seizures were evaluated using the Racine score. To evaluate memory performance, a passive avoidance test was performed before and after PTZ injection. Following euthanasia at the 24th hour of seizure induction, brain tissues were removed for histopathological examination and for evaluating oxidative damage, antioxidant capacity, and neurotransmitter levels. RESULTS: Glutamate/GABA imbalance observed in PTZ rats was corrected by irisin administration (p < 0.001/p < 0.01), while irisin prevented the generation of reactive oxygen species and lipid peroxidation (p < 0.05 - 0.001) and replenished the antioxidant catalase and glutathione levels (p < 0.01-0.01) in the cerebral tissue, and reduced the histologically evident neuronal injury due to a single seizure (p < 0.05 - 0.01). Irisin also delayed the onset of seizures (p < 0.05) and improved memory dysfunction (p < 0.05), but did not affect the severity of seizures. The acute exhaustive swimming exercise completed before PTZ-seizure depressed glutamate level (p < 0.001), maintained the oxidant/antioxidant balance, alleviated neuronal injury (p < 0.05 - 0.01) and upregulated cerebral BDNF expression (p < 0.05). CONCLUSION: In conclusion, acute high-intensity exercise or exogenously administered irisin provides neuroprotection by maintaining the balance of excitatory/inhibitory neurotransmitters and oxidant/antioxidant systems.
Asunto(s)
Fibronectinas , Trastornos de la Memoria , Pentilenotetrazol , Condicionamiento Físico Animal , Ratas Sprague-Dawley , Convulsiones , Animales , Masculino , Trastornos de la Memoria/etiología , Condicionamiento Físico Animal/fisiología , Condicionamiento Físico Animal/métodos , Fibronectinas/metabolismo , Fibronectinas/administración & dosificación , Ratas , Enfermedades Neuroinflamatorias , Epilepsia , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/administración & dosificación , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiologíaRESUMEN
BACKGROUND: Epilepsy is a neurological disease characterized by recurrent seizures, hyperexcitable neurons and various behavioral comorbidities. The electrical charge during seizures depletes the antioxidant defense mechanism in the epileptic brain and increases the oxidative burden. Natural antioxidant compounds are potential therapeutics in the treatment of two major pathologies of epilepsy with their anticonvulsant and anxiolytic effects and can modulate these targets. Gum Arabic is one of the natural plant polysaccharides that is non-toxic and biodegradable. METHODS AND RESULTS: A total of 30 Wistar albino male rats (8-12 weeks, 350-500 g), were randomly divided into 5 groups with 6 animals in each group: 1-Control, 2-Sham (Phosphate buffer saline (PBS)), 3-PTZ, 4-Gum Arabic, 5-PTZ + Gum Arabic. PTZ was administered i.p at 35 mg/kg/day for 11 days. After 48 h, the injection was completed with 75 mg/kg PTZ. Locomotor activity, immobilization, rearing, grooming, eating, and drinking behaviors were recorded with the LABORAS behavior system for 30 min after kindling. Animals were treated with Gum Arabic (2 mg/kg/day, oral gavage) for 10 days. At the end of the period, animal behavior was recorded again. Then the hippocampus tissues were removed. Oxidative parameters (TAS and TOS), early growth response 1 (EGR1) and nuclear receptor subfamily 1 group D member 1 (Rev-erbα) gene expressions and behaviors were analyzed. CONCLUSION: Gum Arabic increased TAS levels (P = 0.000), decreased TOS levels (P = 0.000), and thus exhibited antioxidant properties by reducing oxidative stress burden. EGR1, which was upregulated in the seizure group, was downregulated after treatment (P = 0.000), and Rev-erbα was downregulated in seizure and upregulated after treatment (P = 0.000). Gum arabic may be an antiepileptic and anxiolytic therapeutic in improving epileptic seizures by reducing oxidative stress burden through EGR1 and Rev-erbα.0.
Asunto(s)
Ansiolíticos , Proteína 1 de la Respuesta de Crecimiento Precoz , Epilepsia , Miembro 1 del Grupo D de la Subfamilia 1 de Receptores Nucleares , Animales , Ratas , Anticonvulsivantes , Antioxidantes , Goma Arábiga , Ratas Wistar , Convulsiones , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Miembro 1 del Grupo D de la Subfamilia 1 de Receptores Nucleares/genéticaRESUMEN
Natural compounds are increasingly being studied for their potential neuroprotective effects against inflammatory neurological diseases. Epilepsy is a common neurological disease associated with inflammatory processes, and around 30% of people with epilepsy do not respond to traditional treatments. Some flavonoids, when taken along with antiseizure medications can help reduce the likelihood of drug-resistant epilepsy. Baicalin, a plant-based compound, has been shown to possess pharmacological properties such as anti-inflammatory, neuroprotective, anticonvulsant, and antioxidant activities. In this study, we tested the effect of baicalin on an established model of pharmacologically induced seizure in zebrafish using measures of both locomotor behavior and calcium imaging of neuronal activity. The results of our study showed that, at the tested concentration, and contrary to other studies in rodents, baicalin did not have an anti-seizure effect in zebrafish larvae. However, given its known properties, other concentrations and approaches should be explored to determine if it could potentially have other beneficial effects, either alone or when administered in combination with classic antiseizure medications.
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Calcio , Flavonoides , Larva , Neuronas , Pentilenotetrazol , Convulsiones , Pez Cebra , Animales , Flavonoides/farmacología , Convulsiones/tratamiento farmacológico , Convulsiones/inducido químicamente , Larva/efectos de los fármacos , Calcio/metabolismo , Neuronas/efectos de los fármacos , Modelos Animales de Enfermedad , Anticonvulsivantes/farmacología , Relación Dosis-Respuesta a Droga , Convulsivantes/toxicidad , Locomoción/efectos de los fármacos , Actividad Motora/efectos de los fármacosRESUMEN
Epilepsy ranks as the second-most prevalent neurological disease, and is characterized by seizures resulting in neurobiological and behavioral impairment. Naturally occurring in coffee beans or tea leaves, the alkaloid caffeine (CAF) is the most prevalent global stimulant. Caffeine has been observed to influence epileptic seizures and the efficacy of antiepileptic medications, with a notable impact on topiramate (TPM). This study aimed to explore the influence of CAF on TPM's anticonvulsant effects in zebrafish larvae within a PTZ-induced seizure model, concurrently determining TPM concentrations through a sophisticated analytical approach based on ultrahigh-performance liquid chromatography and subsequent mass spectrometric detection. Zebrafish larvae four days post-fertilization were incubated for 18 h with varying doses of TPM or combinations of CAF + TPM, and locomotor activity was then assessed. Seizures were induced by introducing a PTZ solution to achieve a final concentration of 20 mM. Utilizing liquid chromatography-mass spectrometry (LC-MS/MS), TPM levels in the larvae were quantified. CAF co-administration (especially in higher doses) with TPM caused a decrease in the average locomotor activity in the larvae compared to TPM alone. Moreover, CAF decreased TPM levels in the larvae at all investigated doses. In conclusion, these findings offer a novel perspective on the interplay between CAF and TPM, shedding light on previously unexplored facets. The potential impact of CAF consumption in assisting with epileptic seizure control, unless proven otherwise, suggests a noteworthy consideration for future research and clinical practices.
Asunto(s)
Epilepsia , Pez Cebra , Animales , Topiramato/uso terapéutico , Pentilenotetrazol/toxicidad , Cafeína/farmacología , Cafeína/uso terapéutico , Cromatografía Liquida , Fructosa/efectos adversos , Espectrometría de Masas en Tándem , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico , Anticonvulsivantes/efectos adversos , Epilepsia/tratamiento farmacológicoRESUMEN
Epilepsy is a chronic neurological disorder characterized by recurrent seizures that affects over 70 million people worldwide. Although many antiepileptic drugs that block seizures are available, they have little effect on preventing and curing epilepsy, and their side effects sometimes lead to serious morbidity. Therefore, prophylactic agents with anticonvulsant properties and no adverse effects need to be identified. Recent studies on probiotic administration have reported a variety of beneficial effects on the central nervous system via the microbiota-gut-brain axis. In this study, we investigated the effects of the oral administration of Bifidobacterium breve strain A1 [MCC1274] (B. breve A1) on tonic-clonic seizure in a pentylenetetrazole (PTZ)-induced kindling mouse (KD mouse) model. We found that the oral administration of B. breve A1 every other day for 15 days significantly reduced the seizure score, which gradually increased with repetitive injections of PTZ in KD mice. The administration of B. breve A1, but not saline, to KD mice significantly increased the level of Akt Ser473 phosphorylation (p-Akt) in the hippocampus; this increase was maintained for a minimum of 24 h after PTZ administration. Treatment of B. breve A1-administered KD mice with the selective inhibitor of integrin-linked kinase (ILK) Cpd22 significantly increased the seizure score and blocked the antiepileptic effect of B. breve A1. Moreover, Cpd22 blocked the B. breve A1-induced increase in hippocampal p-Akt levels. These results suggest that the ILK-induced phosphorylation of Akt Ser473 in the hippocampus might be involved in the antiepileptic effect of B. breve A1.
Asunto(s)
Bifidobacterium breve , Modelos Animales de Enfermedad , Excitación Neurológica , Pentilenotetrazol , Probióticos , Proteínas Serina-Treonina Quinasas , Convulsiones , Transducción de Señal , Animales , Probióticos/administración & dosificación , Probióticos/farmacología , Ratones , Convulsiones/metabolismo , Convulsiones/tratamiento farmacológico , Convulsiones/inducido químicamente , Bifidobacterium breve/metabolismo , Masculino , Transducción de Señal/efectos de los fármacos , Administración Oral , Excitación Neurológica/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/metabolismo , Hipocampo/metabolismo , Hipocampo/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , FosforilaciónRESUMEN
Perampanel (PER), a novel 3rd-generation antiseizure drug that modulates altered post-synaptic glutamatergic storming by selectively inhibiting AMPA receptors, is recently approved to treat intractable forms of seizures. However, to date, presumably consequences of long-term PER therapy on the comorbid deleterious psychiatric disturbances and its correlation with neuroinflammatory parameters are not fully investigated in chronic models of epilepsy. Therefore, we investigated the real-time effect of PER on brain electroencephalographic (EEG) activity, behavioral alterations, redox balance, and relative mRNA expression in pentylenetetrazole (PTZ) induced kindling. Male BALB/c mice were pretreated with PER (0.125, 0.25, and 0.5 mg/kg) for 3 weeks and challenged with 11 injections of PTZ at the sub-threshold dose of 40 mg/kg every other day. vEEG from implanted cortical electrodes was monitored to elucidate seizure propagation and behavioral manifestations. Recorded EEG signals exhibited that PER 0.5 mg/kg pretreatment exceptionally impeded the onset of sharp epileptic spike-wave discharges and associated motor symptoms. Additionally, qEEG analysis showed that PER prevented alterations in absolute mean spectral power and reduced RMS amplitude of epileptogenic spikes vs PTZ control. Furthermore, our outcomes illustrated that PER dose-dependently attenuated PTZ-evoked anxiety-like behavior, memory deficits, and depressive-like behavior that was validated by a series of behavioral experiments. Moreover PER, significantly reduced lipid peroxidation, AChE, and increased levels of SOD and total thiol in the mice brain via AMPAR antagonism. Post-PTZ kindling provoked overstimulation of BDNF/TrkB signaling and increased release of pro-inflammatory cytokines that were reversed by PER with suppression of iNOS in brain immune cells. In conclusion, our findings highlight that PER might play an auspicious preventive role in the proepileptic transformation of brain circuits via suppression of BDNF/TrkB signaling and reduced transcriptional levels of neuroinflammatory markers leading to improvised epilepsy-induced neurobehavioral and neurochemical effects.
RESUMEN
This study endeavoured to assess the effect of hemopressin (Hp), a nano peptide obtained from the alpha chain of hemoglobin, on chronic epileptic activity and its potential correlation with cannabinoid receptor type 1 (CB1). Male Wistar albino rats (230-260 g) were used. The kindling process was conducted by administering a sub-convulsant dose of pentylenetetrazol (PTZ) (35 mg/kg, i.p) three times a week for a maximum of 10 weeks. Tripolar electrodes and external cannula guides for intracerebroventricular (i.c.v) injections were surgically implanted in the skulls of kindled rats. On the day of the experiment, doses of Hp, AM-251, and ACEA were administered prior to the PTZ injections. Electroencephalography recordings and behavioural observations were conducted simultaneously for 30 min after the PTZ injection. The administration of Hp (0.6 µg, i.c.v) resulted in a decrease in epileptic activity. The CB1 receptor agonist ACEA (7.5 µg, i.c.v) showed an anticonvulsant effect, but the CB1 receptor antagonist AM-251 (0.5 µg, i.c.v) displayed a proconvulsant effect. The co-administration of Hp (0.6 µg, i.c.v) and ACEA (7.5 µg, i.c.v) and of Hp (0.6 µg, i.c.v) and AM-251 (0.5 µg, i.c.v) produced an anticonvulsant effect. However, when AM-251 was administered prior to Hp, it produced a proconvulsant impact that overrode Hp's intended anticonvulsant effect. Interestingly, the co-administration of Hp (0.03 µg) + AM-251 (0.125 µg) unexpectedly exhibited an anticonvulsant effect. Electrophysiological and behavioural evaluations demonstrated the anticonvulsant effect of Hp in the present model, highlighting the possibility that Hp may act as an agonist for the CB1 receptor.
Asunto(s)
Cannabinoides , Epilepsia , Animales , Ratas , Masculino , Agonistas de Receptores de Cannabinoides/farmacología , Agonistas de Receptores de Cannabinoides/uso terapéutico , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Pentilenotetrazol/farmacología , Receptor Cannabinoide CB1 , Ratas Wistar , Epilepsia/inducido químicamente , Epilepsia/tratamiento farmacológico , Hemoglobinas , Relación Dosis-Respuesta a DrogaRESUMEN
To investigate the molecular mechanism of communication network factor 1 (CCN1) regulating pentylenetetrazol (PTZ)-induced epileptogenesis, deepen the understanding of epilepsy seizure pathogenesis, and provide new drug action targets for its clinical prevention and treatment. Differentially expressed genes (DEGs) on microarrays GSE47516 and GSE88992 were analyzed online using GEO2R. Pathway enrichment and protein-protein interaction network (PPI) analysis of DEGs were carried out using Metascape. Brain tissue samples of severe traumatic brain injury patients (named Healthy group) and refractory epilepsy patients (named Epilepsy group) were obtained and analyzed by qRT-PCR and immunohistochemistry (IHC) staining. A PTZ-induced epilepsy mouse model was established and verified. Morphological changes of neurons in mouse brain tissue were detected using hematoxylin and eosin (HE) staining. qRT-PCR was conducted to detect the mRNA expressions of apoptosis-associated proteins Bax, Caspase-3 and bcl2. TUNEL staining was performed to detect brain neuron apoptosis. The levels of myocardial enzymology, GSH, MDA and ROS in blood of mouse were detected by biochemical assay. CCN1 expression was increased in epilepsy brain tissue samples. CCN1 decreasing effectively prolongs seizure incubation period and decreases seizure duration. Silencing of CCN1 also reduces neuronal damage and apoptosis, decreases mRNA and protein expression of proapoptotic proteins Bax and Caspase-3, increases mRNA expression of antiapoptotic protein Bcl2. Moreover, decrease of CCN1 decreases myocardial enzymatic indexes CK and CK-MB levels, reduces myocardial tissue hemorrhage, and relieves oxidative stress response in hippocampal and myocardial tissue. CCN1 expression is increased in epileptic samples. CCN1 decreasing protects brain tissue by attenuating oxidative stress and inhibiting neuronal apoptosis triggered by PTZ injection, which probably by regulating Nrf2/HO-1 pathway.
Asunto(s)
Epilepsia , Pentilenotetrazol , Humanos , Ratones , Animales , Pentilenotetrazol/efectos adversos , Caspasa 3/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Epilepsia/inducido químicamente , Epilepsia/genética , Epilepsia/tratamiento farmacológico , Convulsiones/inducido químicamente , Estrés Oxidativo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , ARN Mensajero/metabolismoRESUMEN
There is an unmet need to develop alternative therapeutic strategies to not only restrain seizures but also to alleviate the underlying pathologies and sequelae. Berberine (BBR), an isoquinoline alkaloid, has shown promising effect in the kindling model of epileptogenesis, but due to the poor oral bioavailability its clinical application is limited. So, the present study was designed to study the neuroprotective effect of BBR nanoparticles (enhanced bioavailability as compared to BBR) against seizures in pentylenetetrazole (PTZ) induced kindling model of epileptogenesis. Kindling model was established in male Wistar rats by intraperitoneal (i.p.) administration of PTZ (30 mg/kg) on every alternate day till the animal became fully kindled or till 6 weeks. Three doses of BBR (50, 100, and 200 mg/kg) and nano-BBR (25, 50, 100 mg/kg) were studied for seizure score, percentage of animal kindled, histopathological score, oxidative stress, inflammation, and apoptosis in PTZ treated rats by conducting cytokines, gene expression and protein expression analysis. BBR nanoparticles showed significant effect on the seizure score and percentage of animal kindled, histopathological score, neurobehavioral parameters (Forced swim test, Rotarod), oxidative (MDA, SOD, GSH, GPx) and inflammatory (IL-1beta, TNF-alpha) parameters, apoptotic parameters (Bax and iNOS), and gene (Nrf2, NQO1, HO1) and protein expression (Nrf2) as compared to both PTZ and BBR. BBR nanoparticles showed neuroprotective effect in PTZ induced kindling model of epileptogenesis and proves to be a promising antiepileptogenic therapy for the patients who are at high risk of developing seizures.
Asunto(s)
Berberina , Excitación Neurológica , Fármacos Neuroprotectores , Masculino , Ratas , Animales , Pentilenotetrazol/toxicidad , Berberina/farmacología , Berberina/uso terapéutico , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Factor 2 Relacionado con NF-E2/metabolismo , Ratas Wistar , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico , Antiinflamatorios/farmacología , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéuticoRESUMEN
Alchemilla kiwuensis Engl. (Rosaceae) (A. kiwuensis) is an herbaceous plant traditionally used by Cameroonians to treat epilepsy and other central nervous system disorders. The present study evaluated the antiepileptogenic and antiepileptic effects of A. kiwuensis (40 mg/kg, 80 mg/kg) following Pentylenetetrazole (PTZ)-induced kindling as well as its sub-chronic toxicity. Following an initial i.p administration of a challenge dose (70 mg/kg), Wistar rats of both sexes received sub convulsive doses (35 mg/kg) of PTZ every other day, one hour after the oral gavage of animals with treatments, until two consecutive stage 4, in all animals of negative control. Seizure progression, latency, duration, and repetition were noted. Twenty-four hours later, animals were dissected to extract their hippocampi. The resulting homogenates were used to evaluate Malondialdehyde, reduced glutathione, catalase activity, GABA, GABA-Transaminase, glutamate, glutamate transporter 2, IL-1ß and TGF-1 ß. Sub-chronic toxicity was conducted according to OECD 407 guidelines. The lyophilisate of A. kiwuensis significantly increased the latency of seizure appearance, delayed seizure progression and decreased seizure repetition and duration. Biochemical analysis revealed that the lyophilisate significantly increased the catalase activity, reduced glutathione, GABA, glutamate transporter 2 and TGF-1B levels. The lyophilisate equally caused a significant decreased in the GABA-Transaminase activity, malondialdehyde, and IL-1 ß levels. There was no noticeable sign of toxicity. A. kiwuensis possesses antiepileptic and antiepiletogenic effects by enhancing GABAergic neurotransmission and antioxidant properties, coupled to modulation of glutamatergic and neuroinflammatory pathways and is innocuous in a sub-chronic model. These justifies its local use for the treatment of epilepsy.
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Alchemilla , Epilepsia , Excitación Neurológica , Rosaceae , Masculino , Femenino , Ratas , Animales , Pentilenotetrazol/toxicidad , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Catalasa/metabolismo , Rosaceae/metabolismo , Ratas Wistar , Estrés Oxidativo , Epilepsia/inducido químicamente , Epilepsia/tratamiento farmacológico , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico , Convulsiones/prevención & control , Glutatión/metabolismo , Malondialdehído/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Transaminasas/metabolismoRESUMEN
In search of new-structure compounds with good anticonvulsant activity and low neurotoxicity, a series of 3-(1,2,3,6-tetrahydropyridine)-7-azaindole derivatives was designed and synthesized. Their anticonvulsant activities were evaluated by maximal electroshock (MES) and pentylenetetrazole (PTZ) test, and neurotoxicity was determined by the rotary rod method. In the PTZ-induced epilepsy model, compounds 4i, 4p and 5 k showed significant anticonvulsant activities with ED50 values at 30.55 mg/kg, 19.72 mg/kg and 25.46 mg/kg, respectively. However, these compounds did not show any anticonvulsant activity in the MES model. More importantly, these compounds have lower neurotoxicity with protective index (PI = TD50/ED50) values at 8.58, 10.29 and 7.41, respectively. In order to obtain a clearer structure-activity relationship, more compounds were designed rationally based on 4i, 4p and 5 k and their anticonvulsant activities were evaluated on PTZ models. The results demonstrated that the N-atom at the 7-position of the 7-azaindole and the double-bond in the 1,2,3,6-tetrahydropyridine skeleton was essential for antiepileptic activities.
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Anticonvulsivantes , Indoles , Convulsiones , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Anticonvulsivantes/química , Electrochoque , Indoles/uso terapéutico , Pentilenotetrazol , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico , Relación Estructura-Actividad , Ratones , AnimalesRESUMEN
Epilepsy is a chronic condition characterized by recurrent spontaneous seizures. The interaction between astrocytes and neurons has been suggested to play a role in the abnormal neuronal activity observed in epilepsy. However, the exact way astrocytes influence neuronal activity in the epileptogenic brain remains unclear. Here, using the PTZ-induced kindling mouse model, we evaluated the interaction between astrocyte and synaptic function by measuring astrocytic Ca2+ activity, neuronal excitability, and the excitatory/inhibitory balance in the hippocampus. Compared to control mice, hippocampal slices from PTZ-kindled mice displayed an increase in glial fibrillary acidic protein (GFAP) levels and an abnormal pattern of intracellular Ca2+-oscillations, characterized by an increased frequency of prolonged spontaneous transients. PTZ-kindled hippocampal slices also showed an increase in the E/I ratio towards excitation, likely resulting from an augmented release probability of excitatory inputs without affecting inhibitory synapses. Notably, the alterations in the release probability seen in PTZ-kindled slices can be recovered by reducing astrocyte hyperactivity with the reversible toxin fluorocitrate. This suggests that astroglial hyper-reactivity enhances excitatory synaptic transmission, thereby impacting the E/I balance in the hippocampus. Altogether, our findings support the notion that abnormal astrocyte-neuron interactions are pivotal mechanisms in epileptogenesis.
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Epilepsia , Excitación Neurológica , Ratones , Animales , Pentilenotetrazol/efectos adversos , Astrocitos/metabolismo , Epilepsia/metabolismo , Excitación Neurológica/metabolismo , Convulsiones/metabolismo , Hipocampo/metabolismoRESUMEN
Epilepsy is a common neurological disorder characterized by seizures that cause neurobiological and behavioral impairment. Caffeine (CAF), which is the most widely consumed stimulant in the world, is reported to influence epileptic seizures and antiepileptic drugs, especially topiramate (TPM). The aim of the study was to optimize the zebrafish larvae pentylenetetrazol-induced seizure model for the study of CAF and TPM interactions, which include the determination of dose space, and the delivery of an analytical method for monitoring CAF, TPM, and CAF metabolite paraxanthine (PAR) in Zebrafish larvae. Methods: The zebrafish larvae, 4 days post-fertilization, were incubated for 18 h with CAF, TPM, or CAF + TPM, with subsequent locomotor activity assessment. Seizures were evoked by adding PTZ solution to obtain a final concentration of 20 mM. Subsequently, the liquid chromatography-mass spectrometry (LC-MS/MS) analytical method was used to simultaneously assess the levels of both CAF and TPM in the larvae. CAF (50 mg/L) and TPM (75 µM) given separately decreased the average larvae locomotor activity compared to the PTZ group but, however, were not able to lower it to the control level. Co-administration of 25 mg/L CAF and 50 µM TPM suppressed the activity to the same level. Adding 25 µM TPM to 50 mg/L CAF decrease the measured CAF level in the larvae. Until proven otherwise, CAF consumption should be regarded as a potential determinant in the modulation of TPM's efficacy in the management of epileptic seizures. The optimized model will contribute to the standardization of studying CAF and TPM interactions and building the understanding of the molecular bases of the interaction.
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Cafeína , Pentilenotetrazol , Animales , Topiramato/farmacología , Cafeína/farmacología , Pez Cebra , Cromatografía Liquida , Espectrometría de Masas en Tándem , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico , LarvaRESUMEN
The aim of this study was to understand the expression of big potassium (BK, KCa1.1) channels in epileptic seizures under magnetic field application. Forty Wistar albino adult male rats were divided into five groups (n = 8). First group rats were control group. Pentylenetetrazole (PTZ) administrated to second group rats to induce the seizures with 35 mg/kg intraperitoneally injection every two days. Levetiracetam (LEV) i.p. at a dose of 108 mg/kg was given to third group rats as positive control group (PC) before 20 minutes PTZ administration. Pulsed magnetic field with 1.5 mT was exposed to the fourth group rats for 3 hours a day for 1 month as magnetic field (MF) group. 1.5 mT pulsed magnetic field was exposed to the fifth group rats for 3 hours a day for 1 month in addition to PTZ administration (PTZ+MF). KCa1.1 not changed in hippocampus of PTZ rats while increased in frontal cortex and pons for PTZ group but not changed with magnetic field exposure. KCa1.1 increased in heart of PTZ animals and turned back to mean control values with magnetic field exposure. Suppressing the expected increase of c-fos protein expression in seizures with magnetic field application but not being able to change the KCa1.1 expression shows that new studies can be done by increasing the frequency of 1.5 mT magnetic field.
Asunto(s)
Proteínas Proto-Oncogénicas c-fos , Convulsiones , Animales , Masculino , Ratas , Levetiracetam , Campos Magnéticos , Proteínas Proto-Oncogénicas c-fos/genética , Ratas Wistar , Convulsiones/inducido químicamenteRESUMEN
The GABAergic and glutamatergic neurotransmission systems are involved in seizures and other disorders of the central nervous system (CNS). Benzofuran derivatives often serve as the core in drugs used to treat such neurological disorders. The aim of this study was to synthesize new γ-amino acids structurally related to GABA and derived from 2,3-disubstituted benzofurans, analyze in silico their potential toxicity, ADME properties, and affinity for the GluN1-GluN2A NMDA receptor, and evaluate their potential activity and neuronal mechanisms in a murine model of pentylenetetrazol (PTZ)- and 4-aminopyridine (4-AP)-induced seizures. The in silico analysis evidenced a low risk of toxicity for the test compounds as well as the probability that they can cross the blood-brain barrier (BBB) to reach their targets in the CNS. According to docking simulations, these compounds bind at the active site of the NMDA glutamate receptor with high affinity. The in vivo assays demonstrated that 4 protects against 4-AP-induced seizure episodes, suggesting negative allosteric modulation (NAMs) at the glutamatergic NMDA receptor. Contrarily, 3 (the regioisomer of 4) and its racemic derivatives (cis-2,3-dihydrobenzofurans) were previously described to exacerbate such episodes, pointing to their positive allosteric modulation (PAMs) of the same receptor.
Asunto(s)
Benzofuranos , Receptores de N-Metil-D-Aspartato , Aminoácidos , Animales , Benzofuranos/farmacología , Ligandos , Ratones , Pentilenotetrazol , Receptores de N-Metil-D-Aspartato/metabolismoRESUMEN
3-benzyl-5-((2-nitrophenoxy) methyl)-dihydrofuran-2(3 H)-one (3BDO) is a mTOR agonist that inhibits autophagy. The main purpose of this study is to investigate the effects of 3BDO on seizure and cognitive function by autophagy regulation in pentylenetetrazol (PTZ)-kindled epileptic mice model. The PTZ-kindled epileptic mice model was used in study. The behavioral changes and electroencephalogram (EEG) of the mice in each group were observed. The cognitive functions were tested by Morris water maze test. The loss of hippocampal neurons was detected by hematoxylin-eosin (HE) staining and immunofluorescence analysis. Immunohistochemistry, western blot and q-PCR were employed to detect the expression of autophagy-related proteins and mTOR in the hippocampus and cortex. Less seizures, increased hippocampal neurons and reduced astrocytes of hippocampus were observed in the 3BDO-treated epileptic mice than in the PTZ-kindled epileptic mice. Morris water maze test results showed that 3BDO significantly improved the cognitive function of the PTZ-kindled epileptic mice. Western blot analyses and q-PCR revealed that 3BDO inhibited the expression of LC3, Beclin-1, Atg5, Atg7 and p-ULK1/ULK1, but increased that of p-mTOR/mTOR, p-P70S6K/P70S6K in the hippocampus and temporal lobe cortex of epileptic mice. Immunohistochemistry and immunofluorescence also showed 3BDO inhibited the LC3 expression and increased the mTOR expression in the hippocampus of epileptic mice. In addition, the autophagy activator EN6 reversed the decrease in the 3BDO-induced autophagy and aggravated the seizures and cognitive dysfunction in the epileptic mice. 3BDO regulates autophagy by activating the mTOR signaling pathway in PTZ-kindled epileptic mice model, thereby alleviating hippocampus neuronal loss and astrocytes proliferation, reducing seizures and effectively improving cognitive function. Therefore, 3BDO may have potential value in the treatment of epilepsy.
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4-Butirolactona , Epilepsia , Excitación Neurológica , Animales , Ratones , Autofagia , Cognición , Modelos Animales de Enfermedad , Epilepsia/metabolismo , Hipocampo/metabolismo , Pentilenotetrazol , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico , Convulsiones/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , 4-Butirolactona/uso terapéuticoRESUMEN
Pentylenetetrazol (PTZ) blocks the inhibitory action of GABA, triggering a Glu-mediated hyperexcitation of the dendritic spines in hippocampal CA1 pyramidal neurons that leads to the generation of epileptiform seizures. The aim of this work was to determine the effect of PTZ on the electrical activity of the hippocampal pyramidal neurons in male rats. Bipolar electrodes were implanted stereotaxically in the right and left hippocampal CA1 fields of adults, and PTZ (65 mg/kg) was administered i.p. Simultaneous recordings of the field activity and the firing rate (multiunitary activity, MUA) were analyzed at 10, 20, and 30 min post-administration of PTZ. Only rats that presented tonic-clonic seizures during the first 1-5 min after PTZ treatment were included in the study. The recordings of the field activity were analyzed in 4 frequency bands. In both the right and left hippocampal CA1 fields, the relative power corresponding to the slow waves (4-7 Hz) increased, while in the bands 13-30 Hz and 31-50 Hz, it decreased at 10, 20, and 30 min post-PTZ. MUA recordings were analyzed at four levels. The highest levels corresponded to larger amplitudes of the action potentials in the pyramidal neurons. The firing rates of the PTZ-treated rats did not differ from baseline but presented a significant decrement at 10, 20, and 30 min post-PTZ. The decreased firing rate of the hippocampal CA1 pyramidal neurons after PTZ treatment could be associated with plastic changes of dendritic spines along with some microenvironmental adaptations at synaptic level, after neuronal PTZ-mediated hyperexcitation.
Asunto(s)
Pentilenotetrazol , Células Piramidales , Ratas , Masculino , Animales , Pentilenotetrazol/farmacología , Convulsiones/inducido químicamente , Hipocampo , Potenciales de AcciónRESUMEN
Epilepsy is the most common neurological condition worldwide and is largely associated with memory impairment, both in human as well as animal models. Furthermore, differences in seizure onset and severity have already been observed between the sexes. The induction of epilepsy through multiple systemic injections of pentylenetetrazole (PTZ), a protocol known as chemical kindling, is a well-established tool for studies regarding epileptogenesis, as well as the efficacy of antiseizure medication. The aim of this study was to compare possible sex-related differences in seizure severity, memory, neuronal damage as well as the effects of the estrous cycle on seizure severity. Male (nâ¯=â¯10) and Female (nâ¯=â¯11) animals received 30â¯mg/kg i.p. injections three days a week for 6â¯weeks and, after the last application, were tested for short and long-term memory. Control, Male (nâ¯=â¯8) and Female (nâ¯=â¯5) groups did not receive PTZ injections. Although PTZ did not promote important changes into the estrous cycle phases throughout the entire experiment, female animals presented lower seizure scores but had both short and long-term memory impairments associated with cell loss in the hippocampus and anterior cingulate area. Male rats presented higher seizure scores associated with pronounced cell loss, but only long-term memory deficits. Our results demonstrate that the PTZ kindling protocol results in higher seizure scores with increased vulnerability in male rats, but female rats displayed more intense memory deficits.