Pentylenetetrazole-induced Seizures Research Articles

Quercetin Exerts Anticonvulsant Effect through Mitigation of Neuroinflammatory Response in Pentylenetetrazole-induced Seizure in Mice.

Epilepsy is a chronic disease of the brain characterized by seizures. The currently available anticonvulsants only treat symptoms with serious adverse drug reactions. Therefore, there is need for new therapeutic intervention that will prevent epileptogenesis with greater therapeutic success. Quercetin (QT) is a flavonoid with known neuroprotective and anti-inflammatory properties. The study aimed to investigate its effects against pentylenetetrazole (PTZ)-induced seizures. Animals were divided into four groups (n = 10). Group 1(control) only received vehicle (10 mL/kg), group 2 received vehicle, groups 3 and 4 received QT 12.5 mg/kg and 25 mg/kg respectively. Sixty minutes after treatments, animals in groups 2 to 4 were injected with sub-convulsive dose of pentylenetetrazole (35 mg/kg, i.p.) on every alternate day (48±2h) for 21 days. The mice were observed for 30 minutes after each PTZ injection for seizure activity. Brain samples were collected for biochemical assays. Administration of PTZ caused significant increase in the intensity of seizures, neuronal degeneration and level of proinflammatory cytokines in animals compared to control. These behavioural alterations were attenuated significantly by QT (12.5 and 25 mg/kg). The PTZ-induced increase in IL-12, TNF-α and IFN-ɣ were significantly reduced by pre-treatment with the QT (12.5 and 25 mg/kg, p.o). Quercetin also reduced neuronal loss compared to control. Quercetin attenuates seizures in kindled mice and reduces neuroinflammation and neurodegeneration. This neuroprotective effect may be attributed to its ability to inhibit inflammatory mediators in the brain.

Lippia origanoides essential oil possesses anticonvulsant effect in pentylenetetrazol-induced seizures in rats: a behavioral, electroencephalographic, and electromyographic study

Epilepsy is a neuronal disorder characterized by abnormal excitability of the brain, leading to seizures. Only around 66% of the epileptic patients respond adequately to treatment with existing conventional anticonvulsants, making it necessary to investigate new antiepileptic drugs. The growing research into natural products and their pharmacological properties has become increasingly promising, particularly in the study of essential oils, which are already widely used in popular culture for treating various diseases. The present study evaluated the anticonvulsant effects of Lippia origanoides essential oil (LOEO) (100 mg/kg i. p.) compared to diazepam (DZP) (5 mg/kg i. p.), and the combined administration of these two substances to control convulsions induced by pentylenetetrazol (PTZ) (60 mg/kg i. p.). This evaluation was carried out using 108 male Wistar rats, which were divided into two experiments. Experiment 1–Behavioral assessment: The animals were divided into 4 groups (n = 9): (I) saline solution + PTZ, (II) DZP + PTZ, (III) LOEO + PTZ, (IV) LOEO + DZP + PTZ. The convulsive behavior was induced 30 min after the administration of the tested anticonvulsant drugs, and the observation period lasted 30 min. Experiment 2- Electrocorticographic evaluation: The animals were divided into 8 groups (n = 9): (I) saline solution; (II) LOEO; (III) DZP; (IV) LOEO + DZP; (V) saline + PTZ, (VI) DZP + PTZ (VII) LOEO + PTZ, (VIII) LOEO + DZP + PTZ. PTZ was administered 30 min after LOEO and DZP treatments and electrocorticographic activity was assessed for 15 min. For the control groups, electromyographic recordings were performed in the 10th intercostal space to assess respiratory rate. The results demonstrated that Lippia origanoides essential oil increased the latency time for the appearance of isolated clonic seizures without loss of the postural reflex. The animals had a more intense decrease in respiratory rate when combined with LOEO + DZP. EEG recordings showed a reduction in firing amplitude in the LOEO-treated groups. The combining treatment with diazepam resulted in increased anticonvulsant effects. Therefore, treatment with Lippia origanoides essential oil was effective in controlling seizures, and its combination with diazepam may represent a future option for the treatment of difficult-to-control seizures.

Exploring the neuroprotective potential of antimicrobial peptides from Dinoponera quadriceps venom against pentylenetetrazole-induced seizures in vivo

Epilepsy affects around 50 million people worldwide and 30% of patients have difficulty controlling the disease. The search for substances that can fill the existing gaps in the treatment of epilepsy is of great importance. Arthropod venoms are promising sources for this purpose due to the presence of small peptides that modulate the activity of ion channels and neuron receptors. The aim of this study was to investigate dinoponeratoxins from the Dinoponera quadriceps ant venom (M-PONTX-Dq3a, M-PONTX-Dq3b and M-PONTX-Dq3c) as potential anticonvulsants. We evaluated them in a seizure model induced by pentylenetetrazole (PTZ) in male swiss mice. Interestingly, intraperitoneal treatment with each peptide increased the time until the first seizure and the percentage of survival, with M-PONTX-Dq3b showing the best results. M-PONTX-Dq3a was discarded due to the appearance of some signs of toxicity with the increase in malondialdehyde (MDA) levels in the striatum. Both, M-PONTX-Dq3b and M-PONTX-Dq3c decreased iNOS and TNF-α in the hippocampus. Notably, M-PONTX-Dq3c treatment decreased the levels of MDA and nitrite in the cortex and hippocampus. Our results indicate that, M-PONTX-Dq3b and M-PONTX-Dq3c have anticonvulsant activity and exhibit anti-inflammatory effects in epilepsy, offering new perspectives for biopharmaceutical development.

Neuropharmacological Activity of the Acetonic Extract of Malpighia mexicana A. Juss. and Its Phytochemical Profile

Mental and neurological disorders are conditions that affect thoughts, emotions, behavior, and relationships. Malpighia mexicana A. Juss. is a plant used in Mexican traditional medicine for the treatment of such disorders. This work aimed to investigate the antidepressant, anxiolytic, sedative, hypnotic, and anticonvulsant effects of the acetonic extract (MmAE) of M. mexicana and its fractions (F3, F4-10, F14) using the forced swimming test (FST), elevated plus maze (EPM), open field test (OFT), pentobarbital-induced sleep test (PBTt), and pentylenetetrazol-induced seizure test (PTZt). MmAE, F3, F4-10, F14, and vehicle were administrated orally 24, 18, and 1 h prior to the evaluations. Imipramine (15 mg/kg, p.o.) was administrated 1 h prior to the evaluations as a positive control for the FST, while diazepam (1 mg/kg, p.o.) was administrated 1 h prior to the evaluations as a positive control for the EPM, OFT, PBTt, and PTZt. MmAE had an anxiolytic effect; MmAE and F3, F4-10, and F14 showed an antidepressant effect, sedative effect, hypnotic effect, and anticonvulsant effect. Using HPLC, we identified the compounds quercetin 3-O-rutinoside (1), kaempferol 3-O-glucoside (2), luteolin 7-O-glucoside (3), quercetin (4), and kaempferol (5) in MmAE and compounds (1), (2), and (3) in F14. Using GC-MS, we identified α-tocopherol, phytol, and β-amyrin in F3; β-tocopherol, phytol, β-sitosterol, and β-amyrin in F4-10; and α- tocopherol, phytol, β-sitosterol, and β-amyrin in F4-10. The neuropharmacological effects found in this work may be due to the presence of vitamins, phytosterols, terpenes, and flavonoids. This research requires further study to clarify the mechanisms of action of the identified compounds.

Functioning and Gene Expression of Adenosine A1 Receptor During Zebrafish (Danio rerio) Development.

The A1 adenosine receptor is the most widely expressed P1 receptor in vertebrates, performing inhibitory tone of the nervous system. Increased levels of adenosine are crucial to promote tissue protection in threatening situations, such as convulsion and hypoxia. Zebrafish is an established model organism for studies on health and disease. In this study, we evaluated the functionality of A1 adenosine receptor through development of zebrafish (6-7-day-, 3-, 8-, and 24-month-old), assessing: (I) the effects of the agonist N6-cyclopenthyladenosine (CPA) over locomotor parameters, (II) the anticonvulsant properties of CPA and adenosine per se in the pentylenetetrazol-induced seizure, and (III) the gene expression of adora1b through development. CPA promoted decreased distance traveled in the highest concentrations/doses tested (larvae: 75 to 500 μM; adults: 20 mg.kg-1), altered mean velocity (larvae: 50-500 μM; adults: 20 mg.kg-1) and time in the bottom zone of apparatus (adults: decrease in 20 mg.kg-1). Adenosine increased the latency of the larvae to reach stage II at 5 and 10 μM. CPA anticonvulsant effect against convulsive stage II was reached at 75 μM, although it decreased basal locomotor activity in larvae. For adults, CPA 10 mg.kg-1 was effective as anticonvulsant without locomotory effects. Adenosine had minor anticonvulsant effects in the concentration tested (larvae: 5 and 10 μM). The level of gene expression of adora1b was stable in brain from adult animals (8- and 24-month-old animals). These results suggest that zebrafish has similar responses to CPA as mammals. To avoid confounding factors, such as locomotor effects, during any brain function investigation using A1 adenosine receptor as a target, the concentration below 75 μM or below the dose of 20 mg.kg-1 of CPA is ideal for zebrafish at larval and adult stages, respectively.

(-)-α-bisabolol exerts neuroprotective effects against pentylenetetrazole-induced seizures in rats by targeting inflammation and oxidative stress

Epilepsy is the most common neurological disorder which is accompanied with behavioral and psychiatric alternations. Current evidences have shown that (-)-α-bisabolol (BSB) possess anti-inflammatory and antioxidative effects in several animal studies. Here, we conducted present study to evaluate its neuroprotective effects against pentylenetetrazole (PTZ)-induced seizures in rats. We used fifty male rats and they were randomly assigned into 5 groups control, BSB100, PTZ, BSB50 + PTZ, BSB100 + PTZ. The animals intraperitoneally received PTZ (45 mg/kg) for ten consecutive days to induce epilepsy model. BSB in doses of 50 and 100 mg/kg was administrated orally one hour before PTZ administration for ten days. The elevated plus maze (EPM) test was carried out to assess anxiety-like behavior. The seizure intensity was evaluated according to modifies Racine's convulsion scale (RCS). Y-maze and passive avoidance were utilized to assess working memory and aversive memory. The expression of pro-inflammatory cytokines and oxidative stress factors were measured using the enzyme-linked immunosorbent assay (ELISA). The neuronal cell loss in the hilar region was assessed using Nissl staining. Results showed that PTZ-treated rats had more seizure intensity, anxiety-like behavior, memory deficits, higher levels of TNF-α, IL-1β, and oxidative markers. Pre-treatment with BSB 100 significantly inhibited seizure intensity, anxiety-like behavior, and memory deficits; reduced levels of TNF-α, IL-1β, and MDA oxidative markers. Collectively, outcome of this work shows that BSB at the dose of 100 mg/kg may exert neuroprotective effects by mitigating seizures, oxidative stress, and neuroinflammation, and ameliorates memory and anxiety disorders in the PTZ-induced seizure rats.

The Role of Captopril on Pentylenetetrazole-Induced Seizures in Rats

ABSTRACT: 
 Purpose: In recent years, experimental studies have shown that some angiotensin-converting enzyme (ACE) inhibitors with antihypertensive effects have anticonvulsant effects against seizures. After the seizure, the process of inflammation begins in the brain and body, with the production of free radicals. Renin has some effects on the central nervous system of the angiotensin system. The current study's objective was to examine how captopril, an ACE inhibitor, affects neuroinflammation in the hippocampus and cortical areas in acute epileptic seizures and post-seizures induced by pentylenetetrazole (PTZ).
 Material and Methods: Eighteen Wistar Albino rats were separated into three groups: control, PTZ (serum physiologic 1 ml/kg as solvent), and captopril (50 mg/kg/day for 7days). To produce epileptic seizures, PTZ (45 mg/kg) was delivered thirty minutes after the drug was administered. The animals were monitored during 30 minutes to record seizures scoring scale and the onset time of first myoclonic jerk (FMJ). In the brain tissue, the activity of TNF- α, IL-1 β, NF-kB, COX-1, and COX-2 were examined.
 Results: Captopril increased FMJ onset time and reduced seizure stage as compared to the PTZ group (p

Optimization of the Zebrafish Larvae Pentylenetetrazol-Induced Seizure Model for the Study of Caffeine and Topiramate Interactions.

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.

Pentylenetetrazole-Induced Seizures Are Increased after Kindling, Exhibiting Vitamin-Responsive Correlations to the Post-Seizures Behavior, Amino Acids Metabolism and Key Metabolic Regulators in the Rat Brain.

Epilepsy is characterized by recurrent seizures due to a perturbed balance between glutamate and GABA neurotransmission. Our goal is to reveal the molecular mechanisms of the changes upon repeated challenges of this balance, suggesting knowledge-based neuroprotection. To address this goal, a set of metabolic indicators in the post-seizure rat brain cortex is compared before and after pharmacological kindling with pentylenetetrazole (PTZ). Vitamins B1 and B6 supporting energy and neurotransmitter metabolism are studied as neuroprotectors. PTZ kindling increases the seizure severity (1.3 fold, p < 0.01), elevating post-seizure rearings (1.5 fold, p = 0.03) and steps out of the walls (2 fold, p = 0.01). In the kindled vs. non-kindled rats, the post-seizure p53 level is increased 1.3 fold (p = 0.03), reciprocating a 1.4-fold (p = 0.02) decrease in the activity of 2-oxoglutarate dehydrogenase complex (OGDHC) controlling the glutamate degradation. Further, decreased expression of deacylases SIRT3 (1.4 fold, p = 0.01) and SIRT5 (1.5 fold, p = 0.01) reciprocates increased acetylation of 15 kDa proteins 1.5 fold (p < 0.01). Finally, the kindling abrogates the stress response to multiple saline injections in the control animals, manifested in the increased activities of the pyruvate dehydrogenase complex, malic enzyme, glutamine synthetase and decreased malate dehydrogenase activity. Post-seizure animals demonstrate correlations of p53 expression to the levels of glutamate (r = 0.79, p = 0.05). The correlations of the seizure severity and duration to the levels of GABA (r = 0.59, p = 0.05) and glutamate dehydrogenase activity (r = 0.58, p = 0.02), respectively, are substituted by the correlation of the seizure latency with the OGDHC activity (r = 0.69, p < 0.01) after the vitamins administration, testifying to the vitamins-dependent impact of the kindling on glutamate/GABA metabolism. The vitamins also abrogate the correlations of behavioral parameters with seizure duration (r 0.53-0.59, p < 0.03). Thus, increased seizures and modified post-seizure behavior in rats after PTZ kindling are associated with multiple changes in the vitamin-dependent brain metabolism of amino acids, linked to key metabolic regulators: p53, OGDHC, SIRT3 and SIRT5.

Seizure-induced increase in microglial cell population in the developing zebrafish brain

Epilepsy is a chronic brain disorder characterized by unprovoked and recurrent seizures, of which 60% are of unknown etiology. Recent studies implicate microglia in the pathophysiology of epilepsy. However, their role in this process, in particular following early-life seizures, remains poorly understood due in part to the lack of suitable experimental models allowing the in vivo imaging of microglial activity. Given the advantage of zebrafish larvae for minimally-invasive imaging approaches, we sought for the first time to describe the microglial responses after acute seizures in two different zebrafish larval models: a chemically-induced epileptic model by the systemic injection of kainate at 3 days post-fertilization, and the didys552 genetic epilepsy model, which carries a mutation in scn1lab that leads to spontaneous epileptiform discharges. Kainate-treated larvae exhibited transient brain damage as shown by increased numbers of apoptotic nuclei as early as one day post-injection, which was followed by an increase in the number of microglia in the brain. A similar microglial phenotype was also observed in didys552-/- mutants, suggesting that microglia numbers change in response to seizure-like activity in the brain. Interestingly, kainate-treated larvae also displayed a decreased seizure threshold towards subsequent pentylenetetrazole-induced seizures, as shown by higher locomotor and encephalographic activity in comparison with vehicle-injected larvae. These results are comparable to kainate-induced rodent seizure models and suggest the suitability of these zebrafish seizure models for future studies, in particular to elucidate the links between epileptogenesis and microglial dynamic changes after seizure induction in the developing brain, and to understand how these modulate seizure susceptibility.

Effects of berberine on pentylenetetrazole-induced seizures during estrus cycle in rats

Effects of berberine on pentylenetetrazole-induced seizures during estrus cycle in rats

Pharmacometabolic Effects of Pteryxin and Valproate on Pentylenetetrazole-Induced Seizures in Zebrafish Reveal Vagus Nerve Stimulation.

Zebrafish (Danio rerio) assays provide a versatile pharmacological platform to test compounds on a wide range of behaviors in a whole organism. A major challenge lies in the lack of knowledge about the bioavailability and pharmacodynamic effects of bioactive compounds in this model organism. Here, we employed a combined methodology of LC-ESI-MS/MS analytics and targeted metabolomics with behavioral experiments to evaluate the anticonvulsant and potentially toxic effects of the angular dihydropyranocoumarin pteryxin (PTX) in comparison to the antiepileptic drug sodium valproate (VPN) in zebrafish larvae. PTX occurs in different Apiaceae plants traditionally used in Europe to treat epilepsy but has not been investigated so far. To compare potency and efficacy, the uptake of PTX and VPN into zebrafish larvae was quantified as larvae whole-body concentrations together with amino acids and neurotransmitters as proxy pharmacodynamic readout. The convulsant agent pentylenetetrazole (PTZ) acutely reduced the levels of most metabolites, including acetylcholine and serotonin. Conversely, PTX strongly reduced neutral essential amino acids in a LAT1 (SLCA5)-independent manner, but, similarly to VPN specifically increased the levels of serotonin, acetylcholine, and choline, but also ethanolamine. PTX dose and time-dependent manner inhibited PTZ-induced seizure-like movements resulting in a ~70% efficacy after 1 h at 20 µM (the equivalent of 4.28 ± 0.28 µg/g in larvae whole-body). VPN treated for 1 h with 5 mM (the equivalent of 18.17 ± 0.40 µg/g in larvae whole-body) showed a ~80% efficacy. Unexpectedly, PTX (1-20 µM) showed significantly higher bioavailability than VPN (0.1-5 mM) in immersed zebrafish larvae, possibly because VPN in the medium dissociated partially to the readily bioavailable valproic acid. The anticonvulsive effect of PTX was confirmed by local field potential (LFP) recordings. Noteworthy, both substances specifically increased and restored whole-body acetylcholine, choline, and serotonin levels in control and PTZ-treated zebrafish larvae, indicative of vagus nerve stimulation (VNS), which is an adjunctive therapeutic strategy to treat refractory epilepsy in humans. Our study demonstrates the utility of targeted metabolomics in zebrafish assays and shows that VPN and PTX pharmacologically act on the autonomous nervous system by activating parasympathetic neurotransmitters.

In silico molecular modeling, neuro-behavioral profile, and toxicity assessment of the essential oil of Ferula gummosa Boiss. as an anti-seizure agent.

Ferula gummosa Boiss., known in Persian as "Baridje," belongs to the Apiaceae family. All parts of this plant, especially the root, contain galbanum. Galbanum, the oleo-gum resin of F. gummosa, is one of the essential traditional herbal medicines in Iran, which is used as a tonic for epilepsy and chorea, memory enhancement, gastrointestinal diseases, and wound healing. We investigated the toxicity, anticonvulsant effects, and molecular modeling of the essential oil (EO) distilled from the oleo-gum resin of F. gummosa. Gas chromatography-mass spectrometry was used to identify the EO components. The cytotoxicity of EO on HepG2 cell lines was assessed by the MTT method. Male mice were arranged as follows: negative control groups (sunflower oil (10ml/kg, i.p.) or saline (10ml/kg, p.o.)), EO groups (0.5, 1, 1.5, and 2.5ml/kg, p.o.), and positive control groups (ethosuximide (150mg/kg, p.o.) or diazepam (1.0 or 2mg/kg, i.p.)). The motor coordination and neurotoxicity of EO were studied using the rota-rod test. Open-field, novel object recognition, and passive avoidance learning tests were used to investigate the effect of EO on locomotor activity and memory function. An acute pentylenetetrazole-induced seizure model was utilized to evaluate the anticonvulsant properties of the EO. The interaction of the EO main components with the GABAA receptor was investigated by coarse-grained molecular dynamics simulations. β-pinene, sabinene, α-pinene, and ρ-cymene were the main components of EO. The IC50 of the EO at 24, 48, and 72h was found to be 59.90, 12.96, and 3.93μl/ml, respectively. No adverse effects were observed in memory, motor coordination, and locomotor activity in mice treated with EO. Administration of EO (1, 1.5, and 2.5ml/kg) improved survival rates in mice receiving pentylenetetrazole (PTZ; to induce an epileptic seizure). Sabinene was able to bind to the binding site of benzodiazepines at the GABAA receptor. Acute treatment with the EO of F. gummosa caused antiepileptic effects and could effectively increase the survival rate in PTZ-treated mice with no significant toxicity.

Pharmacological Analysis of GABAA Receptor and Sigma1R Chaperone Interaction: Research Report I-Investigation of the Anxiolytic, Anticonvulsant and Hypnotic Effects of Allosteric GABAA Receptors' Ligands.

Two groups of facts have been established in previous drug development studies of the non-benzodiazepine anxiolytic fabomotizole. First, fabomotizole prevents stress-induced decrease in binding ability of the GABAA receptor's benzodiazepine site. Second, fabomotizole is a Sigma1R chaperone agonist, and exposure to Sigma1R antagonists blocks its anxiolytic effect. To prove our main hypothesis of Sigma1R involvement in GABAA receptor-dependent pharmacological effects, we performed a series of experiments on BALB/c and ICR mice using Sigma1R ligands to study anxiolytic effects of benzodiazepine tranquilizers diazepam (1 mg/kg i.p.) and phenazepam (0.1 mg/kg i.p.) in the elevated plus maze test, the anticonvulsant effects of diazepam (1 mg/kg i.p.) in the pentylenetetrazole-induced seizure model, and the hypnotic effects of pentobarbital (50 mg/kg i.p.). Sigma1R antagonists BD-1047 (1, 10, and 20 mg/kg i.p.), NE-100 (1 and 3 mg/kg i.p.), and Sigma1R agonist PRE-084 (1, 5, and 20 mg/kg i.p.) were used in the experiments. Sigma1R antagonists have been found to attenuate while Sigma1R agonists can enhance GABAARs-dependent pharmacological effects.

The Effect of Hydroalcoholic Extract of Salep on Pentylenetetrazole-Induced Seizure in Adult Male Rats

Background and Aim: Epilepsy as a neurological disorder is characterized by unpredictable and periodic seizures. In the present study, the anticonvulsant effect of different doses of salep hydroalcoholic extract on pentylenetetrazole (PTZ) induced seizures was investigated. Methods and Materials/Patients: The animal model of seizure was established by the intraperitoneal injection of pentylenetetrazole (PTZ- 85 mg/kg). Hydroalcoholic extract of salep was administered to the animals in 3 doses (80, 160, and 320 mg/kg). The parameters of the onset and duration of tonic-clonic seizure, total seizure time, balance (falling), and jumping during seizure mortality rate were measured. The results were analyzed by ANOVA test at a significant level of p≤0.05. Results: The results of the current study indicated that salep extract increased the delay in the onset of seizure in the PTZ + extract group in comparison with the PTZ group. The duration of tonic-clonic seizure and the number of falling, jumping, and total seizure times were significantly decreased by salep extract compared to the PTZ group. In the seizure + salep extract, the number and percentage of 24-hour mortality among animals decreased with increasing dosage. All changes were dose-dependent and 320 mg/kg showed the most effect. Conclusion: Extract of salep can probably have anticonvulsant properties, however, further studies are needed to clarify the exact mechanisms.

The sub-chronic Administration of Echium Oil Attenuates the Seizure Threshold and Improves Antioxidant Activity in Pentylenetetrazol-induced Seizure Model of Mice.

Recently polyunsaturated fatty acids (PUFAs) have been considered as the supplementation with no side effects for epilepsy treatment. Echium oil (EO) has been recommended as a novel plant-based source with a significant amount of omega-3 and omega-6. This study evaluates the effects of the sub-chronic consumption of Iranian EO on seizure threshold, antioxidant status, and biochemical parameters in mice with pentylenetetrazol (PTZ)-induced seizures. The study was performed on 5 groups of mice (10 in each group). Group1 and control, had no treatment. Group 2 received sesame oil as a vehicle and groups 3-5 received EO doses of 1gr/kg, 3gr/kg and 5gr/kg, respectively. Administration was performed daily by gavage for 4 weeks. Then, the mice received intravenous PTZ for induction seizure and the threshold of seizure was evaluated. Finally, the animals were sacrificed and the concentration of lipid, Alkaline Phosphatase (ALP), Alanine aminotransferase (ALT), Aspartate Transaminase (AST), Creatinine, and the SOD activity of the serum were determined. Compared to vehicle groups, the sub-chronic administration of EO could increase the seizure threshold dose-dependently. The level of ALT, AST, ALP, Creatinine, HDL, and LDL in EO treatment groups did not change significantly. The level of cholesterol, VLDL (P<0.05), and TG (P<0.01) decreased in the 3gr/kg and 5gr/kg of EO groups. Moreover, the level of SOD activity increased in groups with EO of 1gr/kg and 3gr/kg (P<0.01) but had no change in the group with 5gr/kg EO. We found that the supplementation of Echium Oil attenuated the seizure induced by iv PTZ and had beneficial effects on the blood lipids and antioxidant system with no side effects on effects on the liver and kidney.

Effect of Rosiglitazone, the Peroxisome Proliferator-Activated Receptor (PPAR)-γ Agonist, on Apoptosis, Inflammatory Cytokines and Oxidative Stress in pentylenetetrazole-Induced Seizures in Kindled Mice.

A growing body of evidence has shown that seizure can trigger inflammatory cascades through increasing the expression of several inflammatory cytokines. It has been proved that peroxisome proliferator-activated receptor-γ agonists have immunomodulatory, anti-inflammatory, and neuroprotective effects beyond the putative hypoglycemic effects. Thus, we investigated the inhibitory effect of rosiglitazone on the development of pentylenetetrazol (PTZ)-induced kindling via affecting the inflammatory pathway. Male C57BL/6 mice were randomly divided into vehicle group (0.1% DMSO), PTZ-group and rosiglitazone-PTZ-group. Kindling was induced by the administration of PTZ (40mg/kg, i.p) every other day and mice were observed for 20min after each PTZ injection. Twenty-four hours after the last dose, animals were euthanized and hippocampus was isolated. The level of Malondialdehyde (MDA), Superoxide Dismutase (SOD), and Catalase (CAT) activity were quantified in hippocampus by biochemical methods. The protein levels of IL-1β, IL-6, IL-10, IFN-γ, TNF-α, caspase-3, iNOS, PPAR-γ, Bcl-2, or Bax factors were measured with western blotting. Also, the quantitative real-time PCR were used to evaluate the mRNA expression of those factors. Pretreatment with rosiglitazone significantly prevented the progression of kindling in comparison with control group. The rosiglitazone significantly decreased the MDA level and increased the CAT, and SOD levels in the rosiglitazone treated mice compared to those in the PTZ group (P < 0.01). Using real-time PCR and Western blotting assay, similar results were obtained. The expression levels of IL-1β, IL-6, IL-10, IFN-γ, TNF-α, Bax or PPAR-γ were significantly changed in the brain. The results of this study suggest that effect of rosiglitazone may be crucial in its ability to protect against the neuronal damage caused by PTZ induced seizure.

Reduced uterine perfusion increases hippocampal cannabinoid receptor 1 expression and reduces pentylenetetrazol-induced seizures after rimonabant pre-treatment

Eclampsia, new-onset seizures in pregnant women, can affect women with preeclampsia, a hypertensive pregnancy disorder. Eclampsia is associated with high maternal and fetal morbidity and mortality. The mechanisms contributing to increased risk of seizures in preeclampsia patients are not fully known. One potential mechanism could be abnormal endocannabinoid system activity, and abnormal neuro-modulation. Indeed, increased placental cannabinoid receptor 1 (CB1R) expression and reduced serum concentration of anandamide, a ligand that activates the CB1R, have been reported in preeclampsia patients. We hypothesized that reduced uterine perfusion pressure (RUPP) in mice leads to differences in hippocampal CB1R expression and that inhibiting CB1R activity will increase seizure sensitivity in RUPP mice. Pregnant mice underwent sham (n=5) or RUPP (n=5) surgery on gestational day (GD) 13.5. On GD 18.5, the hippocampus was harvested and processed for Western blot to analyze the expression of CB1R in homogenates, synaptosomal fraction, and cytosolic fraction of the hippocampus. To determine if blocking CB1R increases sensitivity to pentylenetetrazol (PTZ)-induced seizures, additional sham (n=7) and RUPP (n=7) mice were pretreated with 10 mg/kg of rimonabant, video monitored for 15 minutes, injected with 40 mg/kg of PTZ and video monitored for an additional 30 minutes before being sacrificed. Seizures were scored using a modified 7-point Racine scale. In hippocampal homogenates, CB1R expression increased in RUPP mice (p=0.056). There was no difference in CB1R expression in the synaptosomal fraction (p=0.095); however, there was an increase in CB1R expression in the cytosolic fraction of RUPP mice (p=0.016). Immunofluorescence analysis showed increased CB1R colocalization on both glutamate- and GABA- releasing neurons within hippocampal CA1 (p=0.029; p=0.057, respectively). CB1R blockade induced a maximum seizure score of 4 in both groups but led to higher seizure scores over time in RUPP mice (p=0.025). PTZ injection after rimonabant pretreatment increased seizure scores in sham (p&lt;0.05), non-significantly increased scores in RUPP (p=0.075), increased duration of seizures in sham but not RUPP mice (p=0.021; p=0.245, respectively), and reduced latency to seizures in sham mice (p=0.019) while there was no further decrease in seizure latency in RUPP (p=0.374) mice. Furthermore, during the first 15 minutes of PTZ exposure, RUPP mice had lower seizure scores over time than sham [p(TimexRUPP)=0.002] following CB1R blockade. These data suggest that RUPP induces abnormal CB1R expression, resulting in increased sensitivity to seizures after CB1R blockade, while protecting against worse seizures when challenged with the pro-convulsant, PTZ. NIH R00HL129192, R00HL129192-S1, COBRE Pilot Grant, T32HL105324, William Townsend Porter Pre-Doctoral Fellowship from the American Physiological Society, 1F99NS129125-01. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Antiepileptic Properties of Scyllo-Inositol on Pentylenetetrazol-Induced Seizures.

Epilepsy, with about 70 million affected people worldwide, is one of the biggest challenges of medicine today. It is estimated that about one-third of epileptic patients receive inadequate treatment. Inositols have proved effective in many disorders; hence, in the current study, we tested potential antiepileptic properties of scyllo-inositol (SCI)-one of the most common commercially available inositols-in zebrafish larvae with pentylenetetrazol-induced seizures. First, we studied the general effect of SCI on zebrafish motility, and then we tested SCI antiepileptic properties over short (1 h) and long (120 h) exposure protocols. Our results demonstrated that SCI alone does not reduce zebrafish motility regardless of the dose. We also observed that short-term exposure to SCI groups reduced PTZ-treated larva motility compared to controls (p < 0.05). In contrast, prolonged exposure did not produce similar results, likely due to the insufficient concentration of SCI given. Our results highlight the potential of SCI use in epilepsy treatment and warrant further clinical studies with inositols as potential seizure-reducing drugs.

In Vivo Neuropharmacological Effects of Neophytadiene.

Neophytadiene (NPT) is a diterpene found in the methanolic extracts of Crataeva nurvala and Blumea lacera, plants reported with anxiolytic-like activity, sedative properties, and antidepressant-like actions; however, the contribution of neophytadiene to these effects is unknown. This study determined the neuropharmacological (anxiolytic-like, antidepressant-like, anticonvulsant, and sedative) effects of neophytadiene (0.1-10 mg/kg p.o.) and determined the mechanisms of action involved in the neuropharmacological actions using inhibitors such as flumazenil and analyzing the possible interaction of neophytadiene with GABA receptors using a molecular docking study. The behavioral tests were evaluated using the light-dark box, elevated plus-maze, open field, hole-board, convulsion, tail suspension, pentobarbital-induced sleeping, and rotarod. The results showed that neophytadiene exhibited anxiolytic-like activity only to the high dose (10 mg/kg) in the elevated plus-maze and hole-board tests, and anticonvulsant actions in the 4-aminopyridine and pentylenetetrazole-induced seizures test. The anxiolytic-like and anticonvulsant effects of neophytadiene were abolished with the pre-treatment with 2 mg/kg flumazenil. In addition, neophytadiene showed low antidepressant effects (about 3-fold lower) compared to fluoxetine. On other hand, neophytadiene had no sedative or locomotor effects. In conclusion, neophytadiene exerts anxiolytic-like and anticonvulsant activities with the probable participation of the GABAergic system.