ABSTRACT
Camphor, a common aromatic hydrocarbon, is known to be potentially hazardous due to its acute harmful effects primarily on the central nervous system. Contrastingly, camphor is an integral component of various indigenous medicinal potions owing to its medicinal value. Camphor neurotoxicity has been reported in children. However, accidental or voluntary ingestion in adults is rare. We report a patient with voluntary ingestion of camphor, in a relatively large dose for alleviation of a medical condition.
Subject(s)
Camphor , Seizures , Humans , Camphor/poisoning , Seizures/chemically induced , Seizures/drug therapy , Male , AdultABSTRACT
INTRODUCTION: Carbamazepine causes dose-dependent toxicity in overdose. Resources commonly state that severe toxicity occurs with ingestions >50 mg/kg without supporting evidence. We aimed to compare ingested dose with clinical toxicity. METHODS: This was a retrospective series of patients reportedly ingesting carbamazepine >2,000 mg referred to a clinical toxicology unit and state poisons information centre. Medical records were reviewed to extract patient demographics, ingestion details, clinical effects and management. Severe toxicity was defined as the presence of coma (Glasgow Coma Scale <9), seizure, or hypotension (systolic blood pressure <90 mmHg). RESULTS: There were 69 presentations in 42 patients with a median ingested carbamazepine dose of 113 mg/kg (IQR: 71-151 mg/kg). Coma occurred in 10 cases, eight having ingested >200 mg/kg and the remaining two ingesting 113 mg/kg and 151 mg/kg, respectively. Seizures occurred in four cases (lowest ingested dose 143 mg/kg). Hypotension occurred in five cases (lowest ingested dose 113 mg/kg). DISCUSSION: Severe carbamazepine toxicity did not occur with reported ingestions <100 mg/kg and was uncommon in ingestions <200 mg/kg. CONCLUSION: Severe toxicity was common in ingestions >200 mg/kg. Using the suggested threshold of severe toxicity of >50 mg/kg appeared overly conservative in this series.
Subject(s)
Anticonvulsants , Carbamazepine , Dose-Response Relationship, Drug , Drug Overdose , Hypotension , Seizures , Humans , Carbamazepine/poisoning , Carbamazepine/administration & dosage , Retrospective Studies , Male , Female , Adult , Seizures/chemically induced , Middle Aged , Anticonvulsants/poisoning , Anticonvulsants/administration & dosage , Hypotension/chemically induced , Young Adult , Poison Control Centers/statistics & numerical data , Coma/chemically induced , Adolescent , AgedABSTRACT
To present the expression of calsyntenin-1 (Clstn1) in the brain and investigate the potential mechanism of Clstn1 in lithium-pilocarpine rat seizure models. Thirty-five male SD adult rats were induced to have seizures by intraperitoneal injection of lithium chloride pilocarpine. Rats exhibiting spontaneous seizures were divided into the epilepsy (EP) group (n = 15), whereas those without seizures were divided into the control group (n = 14). Evaluate the expression of Clstn1 in the temporal lobe of two groups using Western blotting, immunohistochemistry, and immunofluorescence. Additionally, 55 male SD rats were subjected to status epilepticus (SE) using the same induction method. Rats experiencing seizures exceeding Racine's level 4 (n = 48) were randomly divided into three groups: SE, SE + control lentivirus (lentiviral vector expressing green fluorescent protein [LV-GFP]), and SE + Clstn1-targeted RNA interference lentivirus (LV-Clstn1-RNAi). The LV-GFP group served as a control for the lentiviral vector, whereas the LV-Clstn1-RNAi group received a lentivirus designed to silence Clstn1 expression. These lentiviral treatments were administered via hippocampal stereotactic injection 2 days after SE induction. Seven days after SE, Western blot analysis was performed to evaluate the expression of Clstn1 in the hippocampus and temporal lobe. Meanwhile, we observed the latency of spontaneous seizures and the frequency of spontaneous seizures within 8 weeks among the three groups. The expression of Clstn1 in the cortex and hippocampus of the EP group was significantly increased compared to the control group (p < .05). Immunohistochemistry and immunofluorescence showed that Clstn1 was widely distributed in the cerebral cortex and hippocampus of rats, and colocalization analysis revealed that it was mainly co expressed with neurons in the cytoplasm. Compared with the SE group (11.80 ± 2.17 days) and the SE + GFP group (12.40 ± 1.67 days), there was a statistically significant difference (p < .05) in the latency period of spontaneous seizures (15.14 ± 2.41 days) in the SE + Clstn1 + RNAi group rats. Compared with the SE group (4.60 ± 1.67 times) and the SE + GFP group (4.80 ± 2.05 times), the SE + Clstn1 + RNAi group (2.0 ± .89 times) showed a significant reduction in the frequency of spontaneous seizures within 2 weeks of chronic phase in rats (p < .05). Elevated Clstn1 expression in EP group suggests its role in EP onset. Targeting Clstn1 may be a potential therapeutic approach for EP management.
Subject(s)
Disease Models, Animal , Pilocarpine , Rats, Sprague-Dawley , Seizures , Animals , Male , Pilocarpine/toxicity , Rats , Seizures/metabolism , Seizures/chemically induced , Seizures/genetics , Status Epilepticus/chemically induced , Status Epilepticus/metabolism , Neurocalcin/metabolism , Neurocalcin/genetics , Hippocampus/metabolism , Lithium Chloride , Temporal Lobe/metabolism , Brain/metabolismABSTRACT
Pantoprazole is an extensively used proton pump inhibitor (PPI) for acid peptic disease. PPI rarely cause hypomagnesemia. Hypomagnesemia is commonly associated with hypokalemia and hypocalcemia. Severe hypomagnesemia and hypocalcemia can cause seizures. Here, we report a patient on long-term pantoprazole who presented with generalized tonic-clonic seizures and had severe hypomagnesemia, hypocalcemia, hypokalemia, and secondary hyperparathyroidism. When patients on long-term PPI present with seizures, hypomagnesemia/hypocalcemia has to be excluded.
Subject(s)
Hypocalcemia , Pantoprazole , Proton Pump Inhibitors , Seizures , Pantoprazole/adverse effects , Humans , Proton Pump Inhibitors/adverse effects , Seizures/chemically induced , Hypocalcemia/chemically induced , 2-Pyridinylmethylsulfinylbenzimidazoles/adverse effects , Male , Hypokalemia/chemically induced , Middle Aged , Magnesium Deficiency/chemically inducedABSTRACT
The interplay between circadian rhythms and epilepsy has gained increasing attention. The suprachiasmatic nucleus (SCN), which acts as the master circadian pacemaker, regulates physiological and behavioral rhythms through its complex neural networks. However, the exact role of the SCN and its Bmal1 gene in the development of epilepsy remains unclear. In this study, we utilized a lithium-pilocarpine model to induce epilepsy in mice and simulated circadian disturbances by creating lesions in the SCN and specifically knocking out the Bmal1 gene in the SCN neurons. We observed that the pilocarpine-induced epileptic mice experienced increased daytime seizure frequency, irregular oscillations in core body temperature, and circadian gene alterations in both the SCN and the hippocampus. Additionally, there was enhanced activation of GABAergic projections from the SCN to the hippocampus. Notably, SCN lesions intensified seizure activity, concomitant with hippocampal neuronal damage and GABAergic signaling impairment. Further analyses using the Gene Expression Omnibus database and gene set enrichment analysis indicated reduced Bmal1 expression in patients with medial temporal lobe epilepsy, potentially affecting GABA receptor pathways. Targeted deletion of Bmal1 in SCN neurons exacerbated seizures and pathology in epilepsy, as well as diminished hippocampal GABAergic efficacy. These results underscore the crucial role of the SCN in modulating circadian rhythms and GABAergic function in the hippocampus, aggravating the severity of seizures. This study provides significant insights into how circadian rhythm disturbances can influence neuronal dysfunction and epilepsy, highlighting the therapeutic potential of targeting SCN and the Bmal1 gene within it in epilepsy management.
Subject(s)
Circadian Rhythm , Hippocampus , Mice, Inbred C57BL , Suprachiasmatic Nucleus , Animals , Suprachiasmatic Nucleus/metabolism , Mice , Hippocampus/metabolism , ARNTL Transcription Factors/genetics , ARNTL Transcription Factors/metabolism , Male , Epilepsy/chemically induced , Epilepsy/metabolism , Epilepsy/genetics , Pilocarpine , Seizures/metabolism , Seizures/chemically induced , Seizures/genetics , Seizures/physiopathology , Mice, Knockout , GABAergic Neurons/metabolismABSTRACT
INTRODUCTION: The opioid receptor mu1 is a protein coding gene that can have different codes for a protein and may have variations (polymorphisms) affecting how opioids work. The aim of this study was to investigate the prevalence of the most common opioid receptor mu1 polymorphism (A118G) and any relationship between this polymorphism and features following tramadol overdose. MATERIALS AND METHODS: This was a cross-sectional study of patients admitted with tramadol poisoning to an Iranian hospital. These patients were not taking any other drugs or medications and had no history of seizures. RESULTS: The results showed that among the 83 patients included in the study, 57 (69 per cent) had the AA genotype, 25 (30 per cent) had the AG genotype, and one (1 per cent) had the GG genotype for the opioid receptor mu1 A118G polymorphism. Nausea and/or vomiting occurred in nine (11 per cent) patients and dizziness in 38 (46 per cent) patients. Serious adverse events included seizures in 51 (60 per cent) patients and respiratory failure requiring mechanical ventilation in 21 (25 per cent) patients. However, there was no significant association between the opioid receptor mu1 A118G polymorphism and these adverse events. DISCUSSION: In our study, the frequency of the A allele was greater than the G allele, and the AA genotype was more prevalent than AG. The GG genotype was the least common among the polymorphisms of opioid receptor mu1 rs1799971. There was no significant association between the opioid receptor mu1 A118G polymorphism and symptoms in tramadol-poisoned patients. Although these allele proportions are similar to the results reported in other Caucasian populations, they are dissimilar to the findings in Chinese and Singaporean populations. In these Asian studies, the predominant allele was the G allele. It has been suggested that a mutated G allele will decrease the production of opioid receptor mu1-related messenger ribonucleic acid and related proteins, leading to fewer mu-opioid receptors in the brain. CONCLUSIONS: This study found no significant association between the opioid receptor mu1 A118G polymorphism and adverse outcomes in tramadol-poisoned patients. However, more research is needed to draw more definitive conclusions due to the limited evidence and variability of opioid receptor mu1 polymorphisms in different populations.
Subject(s)
Analgesics, Opioid , Receptors, Opioid, mu , Seizures , Tramadol , Humans , Tramadol/poisoning , Cross-Sectional Studies , Receptors, Opioid, mu/genetics , Male , Female , Adult , Iran , Analgesics, Opioid/poisoning , Analgesics, Opioid/adverse effects , Middle Aged , Seizures/genetics , Seizures/chemically induced , Young Adult , Polymorphism, Single Nucleotide , Drug Overdose/genetics , Genotype , Nausea/chemically induced , Nausea/genetics , Respiratory Insufficiency/chemically induced , Respiratory Insufficiency/genetics , Vomiting/chemically induced , Vomiting/genetics , Adolescent , Dizziness/chemically induced , Dizziness/geneticsABSTRACT
This case report presents an occurrence of three generalized seizures within 30 minutes of ingestion of lysergic acid diethylamide (LSD) in a 15-year-old female patient with treatment-resistant depressive disorder recently started on low-dose lithium therapy. She had no personal or family history of seizure, brain injury or other neurological disorder. The patient had a history of monthly LSD use on several occasions in the setting of ongoing fluoxetine and longacting bupropion (Wellbutrin XL) treatment, with seizures occurring only after initiation of lithium. Although the definitive causal link cannot be established, this case report suggests an increased seizure risk with combination of LSD and lithium, even at subtherapeutic serum lithium levels. This case emphasizes the need for further research, careful clinical practice, and patient education regarding the potential dangers of using psychedelic substances with psychopharmacological treatment.
Subject(s)
Lysergic Acid Diethylamide , Seizures , Humans , Female , Adolescent , Lysergic Acid Diethylamide/adverse effects , Seizures/chemically induced , Seizures/drug therapy , Hallucinogens/adverse effects , Hallucinogens/administration & dosage , Depressive Disorder, Treatment-Resistant/drug therapyABSTRACT
In order to investigate the effectiveness and safety of miR-23b-3p in anti-seizure activity and to elucidate the regulatory relationship between miR-23b-3p and Cx43 in the nervous system, we have established a lithium chloride-pilocarpine (PILO) status epilepticus (SE) model. Rats were randomly divided into the following groups: seizure control (PILO), valproate sodium (VPA+PILO), recombinant miR-23b-3p overexpression (miR+PILO), miR-23b-3p sponges (Sponges+PILO), and scramble sequence negative control (Scramble+PILO) (n = 6/group). After experiments, we got the following results. In the acute phase, the time required for rats to reach stage IV after PILO injection was significantly longer in VPA+PILO and miR+PILO. In the chronic phase after SE, the frequency of spontaneous recurrent seizures (SRSs) in VPA+PILO and miR+PILO was significantly reduced. At 10 min before seizure cessation, the average energy expression of fast ripples (FRs) in VPA+PILO and miR+PILO was significantly lower than in PILO. After 28 days of seizure, Cx43 expression in PILO was significantly increased, and Beclin1expression in all groups was significantly increased. After 28 days of SE,the number of synapses in the CA1 region of the hippocampus was significantly higher in the VPA+PILO and miR+PILO groups compared to that in the PILO group. After 28 days of SE ,hippocampal necrotic cells in the CA3 region were significantly lower in the VPA+PILO and miR+PILO groups compared to those in the PILO group. There were no significant differences in biochemical indicators among the experimental group rats 28 days after SE compared to the seizure control group. Based on the previous facts, we can reach the conclusion that MiR-23b-3p targets and blocks the expression of hippocampal Cx43 which can reduce the formation of pathological FRs, thereby alleviating the severity of seizures, improving seizure-induced brain damage.
Subject(s)
Connexin 43 , Hippocampus , MicroRNAs , Rats, Sprague-Dawley , Status Epilepticus , Animals , Male , Rats , Brain Injuries/metabolism , Connexin 43/metabolism , Connexin 43/genetics , Disease Models, Animal , Hippocampus/metabolism , Hippocampus/drug effects , MicroRNAs/metabolism , MicroRNAs/genetics , Pilocarpine/toxicity , Seizures/metabolism , Seizures/chemically induced , Status Epilepticus/chemically induced , Status Epilepticus/metabolismABSTRACT
BACKGROUND: Status epilepticus (SE) as a severe neurodegenerative disease, greatly negatively affects people's health, and there is an urgent need for innovative treatments. The valuable neuroprotective effects of glucagon-like peptide-1 (GLP-1) in several neurodegenerative diseases have raised motivation to investigate the dipeptidyl peptidase-4 (DPP-4) inhibitor; alogliptin (ALO), an oral antidiabetic drug as a potential treatment for SE. ALO has shown promising neuroprotective effects in Alzheimer's and Parkinson's diseases, but its impact on SE has not yet been studied. AIM: The present study aimed to explore the repurposing potential for ALO in a lithium/pilocarpine (Li/Pil)-induced SE model in rats. MAIN METHODS: ALO (30 mg/kg/day) was administered via gavage for 14 days, and SE was subsequently induced in the rats using a single dose of Li/Pil (127/60 mg/kg), while levetiracetam was used as a standard antiepileptic drug. KEY FINDINGS: The results showed that ALO reduced seizure severity and associated hippocampal neurodegeneration. ALO also increased γ-aminobutyric acid (GABA) levels, diminished glutamate spikes, and corrected glial fibrillary acidic protein (GFAP) changes. At the molecular level, ALO increased GLP-1 levels and activated its downstream signaling pathway, AMP-activated protein kinase (AMPK)/sirtuin-1 (SIRT1). ALO also dampened the brain's pro-oxidant response, curbed neuroinflammation, and counteracted hippocampal apoptosis affording neuroprotection. In addition, it activated autophagy as indicated by Beclin1 elevation. SIGNIFICANCE: This study suggested that the neuroprotective properties and autophagy-enhancing effects of ALO make it a promising treatment for SE and can potentially be used as a management approach for this condition.
Subject(s)
Autophagy , NF-E2-Related Factor 2 , Neuroprotective Agents , Pilocarpine , Piperidines , Seizures , Sirtuin 1 , Animals , Rats , Sirtuin 1/metabolism , Neuroprotective Agents/pharmacology , Male , Autophagy/drug effects , Piperidines/pharmacology , NF-E2-Related Factor 2/metabolism , Seizures/chemically induced , Seizures/drug therapy , Seizures/metabolism , Lithium/pharmacology , AMP-Activated Protein Kinases/metabolism , Uracil/analogs & derivatives , Uracil/pharmacology , Rats, Sprague-Dawley , Hippocampus/drug effects , Hippocampus/metabolism , Hippocampus/pathology , Status Epilepticus/chemically induced , Status Epilepticus/drug therapy , Status Epilepticus/metabolism , Signal Transduction/drug effectsABSTRACT
Currently, pharmacotherapy provides successful seizure control in around 70% of patients with epilepsy; however, around 30% of cases are still resistant to available treatment. Therefore, effective anti-epileptic therapy still remains a challenge. In our study, we utilized two mouse lines selected for low (LA) and high (HA) endogenous opioid system activity to investigate the relationship between down- or upregulation of the opioid system and susceptibility to seizures. Pentylenetetrazole (PTZ) is a compound commonly used for kindling of generalized tonic-clonic convulsions in animal models. Our experiments revealed that in the LA mice, PTZ produced seizures of greater intensity and shorter latency than in HA mice. This observation suggests that proper opioid system tone is crucial for preventing the onset of generalized tonic-clonic seizures. Moreover, a combination of an opioid receptor antagonist-naloxone-and a GABA receptor agonist-diazepam (DZP)-facilitates a significant DZP-sparing effect. This is particularly important for the pharmacotherapy of neurological patients, since benzodiazepines display high addiction risk. In conclusion, our study shows a meaningful, protective role of the endogenous opioid system in the prevention of epileptic seizures and that disturbances in that balance may facilitate seizure occurrence.
Subject(s)
Pentylenetetrazole , Seizures , Animals , Pentylenetetrazole/toxicity , Mice , Seizures/metabolism , Seizures/drug therapy , Seizures/chemically induced , Male , Naloxone/pharmacology , Disease Models, Animal , Diazepam/pharmacology , Disease Susceptibility , Anticonvulsants/pharmacology , Anticonvulsants/therapeutic use , Narcotic Antagonists/pharmacologyABSTRACT
Epilepsy, a chronic neurological disorder characterized by recurrent unprovoked seizures, presents a substantial challenge in approximately one-third of cases exhibiting resistance to conventional pharmacological treatments. This study investigated the effect of 4-allyl-2,6-dimethoxyphenol, a phenolic compound derived from various natural sources, in different models of induced seizures and its impact on animal electroencephalographic (EEG) recordings. Adult male Swiss albino mice were pre-treated (i.p.) with a dose curve of 4-allyl-2,6-dimethoxyphenol (50, 100, or 200â¯mg/kg), its vehicle (Tween), or standard antiepileptic drug (Diazepam; or Phenytoin). Subsequently, the mice were subjected to different seizure-inducing models - pentylenetetrazole (PTZ), 3-mercaptopropionic acid (3-MPA), pilocarpine (PILO), or maximal electroshock seizure (MES). EEG analysis was performed on other animals surgically implanted with electrodes to evaluate brain activity. Significant results revealed that animals treated with 4-allyl-2,6-dimethoxyphenol exhibited increased latency to the first myoclonic jerk in the PTZ and PILO models; prolonged latency to the first tonic-clonic seizure in the PTZ, 3-MPA, and PILO models; reduced total duration of tonic-clonic seizures in the PTZ and PILO models; decreased intensity of convulsive seizures in the PTZ and 3-MPA models; and diminished mortality in the 3-MPA, PILO, and MES models. EEG analysis indicated an increase in the percentage of total power attributed to beta waves following 4-allyl-2,6-dimethoxyphenol administration. Notably, the substance protected from behavioral and electrographic seizures in the PTZ model, preventing increases in the average amplitude of recording signals while also inducing an increase in the participation of theta and gamma waves. These findings suggest promising outcomes for the tested phenolic compound across diverse pre-clinical seizure models, highlighting the need for further comprehensive studies to elucidate its underlying mechanisms and validate its clinical relevance in epilepsy management.
Subject(s)
Anticonvulsants , Disease Models, Animal , Electroencephalography , Electroshock , Pentylenetetrazole , Seizures , Animals , Male , Seizures/drug therapy , Seizures/chemically induced , Seizures/physiopathology , Mice , Anticonvulsants/pharmacology , Pentylenetetrazole/toxicity , Electroencephalography/drug effects , Anisoles/pharmacology , Dose-Response Relationship, Drug , Pilocarpine/toxicity , Brain/drug effects , Brain/physiopathology , 3-Mercaptopropionic Acid/pharmacology , Convulsants/toxicityABSTRACT
BACKGROUND: Seizures are considered to be one of the dreaded side effects of clozapine, and due to this, the use of clozapine is avoided in patients with treatment-resistant schizophrenia. Resultantly, there is little information about the use of clozapine among patients with seizure disorder. AIM: To assess the safety of clozapine in patients with history of seizures in their lifetime before starting clozapine and receiving clozapine for the management of psychotic disorders. RESULTS: Out of the 958 patients, 35 (3.65â¯%) had a history of at least one seizure episode before starting clozapine, with a mean of 5.06 (SD: 7.23; Median: 3.00) seizures before starting clozapine. The mean duration between the last seizure and the starting of clozapine was 123.75 (SD: 124.99; Median: 84) months, with nine patients having an episode of seizure in the previous 12 months and 15 patients being seizure-free for more than ten years. About one-fourth (25.7â¯%; nine out of 35) of the patients had recurrence of seizure while receiving clozapine for a mean duration of about five years. When the recurrence of seizure after starting clozapine was evaluated in patients receiving antiepileptics along with clozapine, the incidence of at least one seizure was 26.67â¯% (4 out of 15), and among those not receiving antiepileptics, the incidence of at least one seizure was 25â¯% (5 out of 20). The dose of clozapine at which seizure was noted ranged from 12.5â¯mg to 600â¯mg/day with a mean of 236.25 (SD: 169.04; Median: 162.5) mg/day. In none of the patients, clozapine had to be stopped due to the continuation of seizures. CONCLUSION: About one-fourth of the patients with history of an episode of seizure have recurrence of seizure while receiving clozapine. The demographic and clinical variables do not differ between those who develop and who do not develop seizures after starting clozapine, including concomitant use of antiepileptics.
Subject(s)
Antipsychotic Agents , Clozapine , Seizures , Humans , Clozapine/adverse effects , Clozapine/administration & dosage , Adult , Antipsychotic Agents/adverse effects , Antipsychotic Agents/administration & dosage , Female , Male , Seizures/drug therapy , Seizures/chemically induced , Retrospective Studies , Middle Aged , Anticonvulsants/adverse effects , Anticonvulsants/administration & dosage , Schizophrenia, Treatment-Resistant/drug therapy , Young Adult , Recurrence , Schizophrenia/drug therapy , Psychotic Disorders/drug therapyABSTRACT
Despite extensive temporal lobe epilepsy (TLE) research, understanding the specific limbic structures' roles in seizures remains limited. This weakness can be attributed to the complex nature of TLE and the existence of various TLE subsyndromes, including non-lesional TLE. Conventional TLE models like kainate and pilocarpine hinder precise assessment of the role of individual limbic structures in TLE ictogenesis due to widespread limbic damage induced by the initial status epilepticus. In this study, we used a non-lesional TLE model characterized by the absence of initial status and cell damage to determine the spatiotemporal profile of seizure initiation and limbic structure recruitment in TLE. Epilepsy was induced by injecting a minute dose of tetanus toxin into the right dorsal hippocampus in seven animals. Following injection, animals were implanted with bipolar recording electrodes in the amygdala, dorsal hippocampus, ventral hippocampus, piriform, perirhinal, and entorhinal cortices of both hemispheres. The animals were video-EEG monitored for four weeks. In total, 140 seizures (20 seizures per animal) were analyzed. The average duration of each seizure was 53.2+/-3.9 s. Seizure could initiate in any limbic structure. Most seizures initiated in the ipsilateral (41 %) and contralateral (18 %) ventral hippocampi. These two structures displayed a significantly higher probability of seizure initiation than by chance. The involvement of limbic structures in seizure initiation varied between individual animals. Surprisingly, only 7 % of seizures initiated in the injected dorsal hippocampus. The limbic structure recruitment into the seizure activity wasn't random and displayed consistent patterns of early recruitment of hippocampi and entorhinal cortices. Although ventral hippocampus represented the primary seizure onset zone, the study demonstrated the involvement of multiple limbic structures in seizure initiation in a non-lesional TLE model. The study also revealed the dichotomy between the primary epileptogenic lesion and main seizure onset zones and points to the central role of ventral hippocampi in temporal lobe ictogenesis.
Subject(s)
Disease Models, Animal , Epilepsy, Temporal Lobe , Seizures , Tetanus Toxin , Epilepsy, Temporal Lobe/chemically induced , Epilepsy, Temporal Lobe/physiopathology , Epilepsy, Temporal Lobe/pathology , Animals , Male , Tetanus Toxin/toxicity , Seizures/chemically induced , Seizures/physiopathology , Rats , Rats, Sprague-Dawley , Hippocampus/drug effects , Hippocampus/pathology , ElectroencephalographyABSTRACT
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.
Subject(s)
Neuroinflammatory Diseases , Oxidative Stress , Pentylenetetrazole , Seizures , Animals , Mice , Seizures/metabolism , Seizures/chemically induced , Seizures/pathology , Male , Neuroinflammatory Diseases/metabolism , Neuroinflammatory Diseases/etiology , Neuroinflammatory Diseases/pathology , Stress, Psychological/complications , Stress, Psychological/metabolism , Hippocampus/metabolism , Hippocampus/pathology , Chronic Disease , Behavior, AnimalABSTRACT
GABA modulators such as phenobarbital (PB) and sodium channel blockers such as phenytoin (PHT) have long been the mainstay of pharmacotherapy for the epilepsies. In the context of neonatal seizures, both PB and PHT display incomplete clinical efficacy. Moreover, in animal models, neonatal exposure to these medications result in neurodegeneration raising concerns about safety. Cenobamate, a more recently approved medication, displays unique pharmacology as it is both a positive allosteric modulator of GABA-A receptors, and a voltage-gated sodium channel blocker. While cenobamate is approved for adult use, its efficacy and safety profile against neonatal seizures is poorly understood. To address this gap, we assessed the efficacy and safety of cenobamate in immature rodents. Postnatal day (P)7 rat pups were pretreated with cenobamate and challenged with the chemoconvulsant pentylenetetrazole (PTZ) to screen for anti-seizure effects. In a separate experiment, P7 rats were treated with cenobamate, and brains were processed to assess induction of cell death. Cenobamate displays dose-dependent anti-seizure efficacy in neonatal rats. Unlike PHB and PHT, it does not induce neurotoxicity in P7 rats. Thus, cenobamate may be effective at treating neonatal seizures while avoiding unwanted neurotoxic side effects such as cell death.
Subject(s)
Animals, Newborn , Anticonvulsants , Carbamates , Cell Death , Disease Models, Animal , Dose-Response Relationship, Drug , Rats, Sprague-Dawley , Seizures , Animals , Seizures/chemically induced , Seizures/drug therapy , Anticonvulsants/pharmacology , Rats , Cell Death/drug effects , Carbamates/pharmacology , Carbamates/therapeutic use , Chlorophenols/pharmacology , Pentylenetetrazole/toxicity , Male , Female , Convulsants/toxicity , Brain/drug effects , TetrazolesABSTRACT
Zebrafish larvae exposed to chemoconvulsants show behavioral seizures and electrographic abnormalities similar to the other mammalian models, making it a potential tool in epilepsy research. During the embryonic stage, zebrafish remains transparent which enables real-time developmental detection and in-situ gene/protein expression. However, pigmentation during the larval stage restricts transparency. Phenylthiourea (1-phenyl-2-thiourea; PTU) is a commonly used pigmentation blocker that maintains larval transparency. It is widely used along with chemoconvulsants to study in situ expressions in epileptic larvae, however, its effect on seizures largely remains unknown. Therefore, in the present study, the effect of PTU-mediated depigmentation was studied on pentylenetetrazol (PTZ)-induced seizures in zebrafish larvae. After spawning, the fish embryos were subjected to standard depigmentation protocol using 0.13 mM PTU. At 7-days post fertilization seizures were induced using 8 mM PTZ. PTU exposure significantly reduced PTZ-mediated hyperactive responses indicated by decreased distance travelled and swimming velocity of the larvae. Furthermore, PTU-exposed depigmented larvae also showed an increase in the latency to the onset of PTZ-mediated clonic-like seizures. The results concluded that PTU depigmentation protocol reduces the seizurogenic response of PTZ, hence its usage for imaging zebrafish larvae must be carefully monitored to avoid erroneous results.
Subject(s)
Larva , Pentylenetetrazole , Phenylthiourea , Seizures , Zebrafish , Animals , Zebrafish/embryology , Larva/drug effects , Phenylthiourea/pharmacology , Seizures/chemically induced , Pigmentation/drug effects , Disease Models, Animal , ConvulsantsABSTRACT
OBJECTIVE: This review aims to summarize existing evidence on the adverse pregnancy outcomes and seizure control effects of using lamotrigine (LTG) monotherapy in pregnancy women with epilepsy (WWE) during pregnancy. METHODS: A comprehensive search was conducted in various databases including Cochrane, Web of Science, CBM, PubMed, Embase, CNKI, and Pregnancy Registration Center databases to identify relevant studies. The search was concluded up to January 2024. Studies comparing LTG with other antiseizure medications (ASMs) for treating epilepsy in pregnant women were included, with no language or regional restrictions. RESULTS: A total of 19 studies were included for analysis, with 16 studies reporting adverse pregnancy outcomes and 6 studies reporting seizure control outcomes. Meta-analysis showed that compared to monotherapy with carbamazepine (CBZ), sodium valproate (VPA), and levetiracetam (LEV), LTG monotherapy had a slightly weaker ability to control seizures during pregnancy, with ORs and 95 %CIs of 0.65 (0.57-0.75; CBZ), 0.50 (0.32-0.79; VPA), and 0.55 (0.36-0.84; LEV). Regarding adverse pregnancy outcomes, the occurrence rate of LTG monotherapy was significantly lower than that of CBZ, VPA, phenytoin (PHT), and phenobarbital (PHB), with ORs and 95 %CIs ranging from 0.30 (0.25-0.35; VPA) to 0.68 (0.56-0.81; CBZ). CONCLUSION: Based on meta-analysis, LTG and LEV appear to be preferred medications for controlling seizures during pregnancy. This review provides further support for the use of LTG monotherapy in pregnant WWE, building upon existing evidence for clinical practitioners.
Subject(s)
Anticonvulsants , Epilepsy , Lamotrigine , Pregnancy Complications , Seizures , Humans , Pregnancy , Female , Anticonvulsants/adverse effects , Anticonvulsants/therapeutic use , Lamotrigine/therapeutic use , Lamotrigine/adverse effects , Pregnancy Complications/drug therapy , Seizures/drug therapy , Seizures/chemically induced , Epilepsy/drug therapy , Pregnancy Outcome/epidemiologyABSTRACT
BACKGROUND: The local anaesthetic lidocaine is widely used in the neonatal intensive unit to treat seizures in premature babies. However, other antiepileptics administered during early development in various animal models have shown negative long-term behavioural effects. Since no long-term behavioural data so far exist regarding lidocaine exposure at an early age, we decided to perform this extended follow-up study using a sensitive behavioural test. METHODS: Neonatal mice received a subcutaneous administration of saline or one dose of lidocaine (0.5, 4, or 12 mg kg-1) on postnatal day 10 (P10; peak of the Brain Growth Spurt). A well-established test to detect long-term behavioural alterations was conducted at 2 and 6 months of age, corresponding to early and late adulthood in humans. RESULTS: All animal survived to later testing. No signs of acute toxicity were observed. Lidocaine exposure did not result in any negative behavioural effects during habituation to a new home environment at any of the two studied time points, compared to saline placebo. CONCLUSIONS: Lidocaine does not by itself produce any negative long-term behavioural effects in mice exposed in early life (P10) despite long-term follow-up. This is reassuring regarding the current practice of treating seizures in premature babies with intravenous lidocaine.
Subject(s)
Anesthetics, Local , Animals, Newborn , Behavior, Animal , Lidocaine , Animals , Lidocaine/toxicity , Lidocaine/pharmacology , Lidocaine/administration & dosage , Mice , Behavior, Animal/drug effects , Anesthetics, Local/toxicity , Anesthetics, Local/administration & dosage , Male , Female , Seizures/chemically induced , Dose-Response Relationship, DrugABSTRACT
Seizures are a concerning adverse event frequently associated with the use of psychedelics, and hence, studies involving these substances tend to exclude patients with past history of epilepsy. This is especially relevant because epileptic seizures are markedly increased in the population suffering from mental disorders, and psychedelic assisted therapy is being researched as a promising treatment for several of them. To determine the extent of the current literature on the relationship between classic psychedelics and seizures, a scoping review was performed using the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews). The search was conducted in PubMed, Web of Science, Google scholar, LILACS and Scielo, and both animal and human models were included. A total of 16 publications on humans, and 11 on animals, were found. The results are heterogeneous, but globally suggest that psychedelics may not increase the risk of seizures in healthy individuals or animals in the absence of other drugs. However, concomitant use of other substances or drugs, such as kambo or lithium, could increase the risk of seizures. Additionally, these conclusions are drawn from data lacking sufficient external validity, so they should be interpreted with caution. Future paths for research and a summary on possible neurobiological underpinnings that might clarify the relationship between classical psychedelics and seizures are also provided.