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Neuroscience Letters Jun 2024Brain somatic variants in SLC35A2, an intracellular UDP-galactose transporter, are commonly identified mutations associated with drug-resistant neocortical epilepsy and...
Brain somatic variants in SLC35A2, an intracellular UDP-galactose transporter, are commonly identified mutations associated with drug-resistant neocortical epilepsy and developmental brain malformations, including focal cortical dysplasia type I and mild malformation of cortical development with oligodendroglial hyperplasia in epilepsy (MOGHE). However, the causal effects of altered SLC35A2 function on cortical development remain untested. We hypothesized that focal Slc35a2 knockout (KO) or knockdown (KD) in the developing mouse cortex would disrupt cortical development and change network excitability. Through two independent studies, we used in utero electroporation (IUE) to introduce CRISPR/Cas9/targeted guide RNAs or short-hairpin RNAs into the embryonic mouse brain at day 14.5-15.5 to achieve Slc35a2 KO or KD, respectively, from neural precursor cells. Slc35a2 KO or KD caused disrupted radial migration of electroporated neurons evidenced by heterotopic cells located in lower cortical layers and in the sub-cortical white matter. Slc35a2 KO in neurons did not induce changes in oligodendrocyte number, importantly suggesting that the oligodendroglial hyperplasia observed in MOGHE originates from distinct cell autonomous effects of Slc35a2 mutations. Adult KO mice were implanted with EEG electrodes for 72-hour continuous recording. Spontaneous seizures were not observed in focal Slc35a2 KO mice, but there was reduced seizure threshold following pentylenetetrazol injection. Here we demonstrate that focal Slc35a2 KO or KD in vivo disrupts corticogenesis through altered neuronal migration and that KO leads to reduced seizure threshold. Together these results demonstrate a direct causal role for SLC35A2 in cortical development.
PubMed: 38909838
DOI: 10.1016/j.neulet.2024.137881 -
Nan Fang Yi Ke Da Xue Xue Bao = Journal... Mar 2024To explore the inhibitory effect of saikosonin a (SSa) on pentylenetetrazol-induced acute epilepsy seizures in a mouse model of depression and explore the mechanism...
OBJECTIVE
To explore the inhibitory effect of saikosonin a (SSa) on pentylenetetrazol-induced acute epilepsy seizures in a mouse model of depression and explore the mechanism mediating this effect.
METHODS
Male C57BL/6J mouse models of depression was established by oral administration of corticosterone drinking water for 3 weeks, and acute epileptic seizures were induced by intraperitoneal injection of a single dose of pentylenetetrazole. The effect of intraperitoneal injection of SSa prior to the treatment on depressive symptoms and epileptic seizures were assessed using behavioral tests, epileptic seizure grading and hippocampal morphology observation. ELISA was used to detect blood corticosterone levels of the mice, and RTqPCR was performed to detect the pro- and anti-inflammatory factors. Microglia activation in the mice was observed using immunofluorescence staining.
RESULTS
The mouse model of corticosterone-induced depression showed body weight loss and obvious depressive behaviors with significantly increased serum corticosterone level (all < 0.05). Compared with those with pentylenetetrazole-induced epilepsy alone, the epileptic mice with comorbid depression showed significantly shorter latency of epileptic seizures, increased number, grade and duration of of seizures, reduced Nissl bodies in hippocampal CA1 and CA3 neurons, increased number of Iba1-positive cells, and significantly enhanced hippocampal expressions of IL-1β, IL-10, TNF-α and IFN-γ. Pretreatment of the epileptic mice with SSa significantly prolonged the latency of epileptic seizures, reduced the number, duration, and severity of seizures, increased the number of Nissl bodies, decreased the number of Iba1-positive cells, and reduced the expression levels of IL-1β, IL-10, TNF-α, and IFN-γ in the hippocampus ( < 0.05).
CONCLUSION
Depressive state aggravates epileptic seizures, increases microglia activation, and elevates inflammation levels. SSA treatment can alleviate acute epileptic seizures in mouse models of depression possibly by suppressing microglia activation-mediated inflammation.
Topics: Male; Mice; Animals; Pentylenetetrazole; Interleukin-10; Microglia; Tumor Necrosis Factor-alpha; Depression; Corticosterone; Mice, Inbred C57BL; Seizures; Epilepsy; Hippocampus; Inflammation; Interleukin-1beta; Disease Models, Animal; Oleanolic Acid; Saponins
PubMed: 38597443
DOI: 10.12122/j.issn.1673-4254.2024.03.13 -
Toxics Sep 2023This study investigated the effect of L. (RO) extract on neurobehavioral and neurobiological changes in male rats with pentylenetetrazol (PTZ)-induced epilepsy. Rats...
This study investigated the effect of L. (RO) extract on neurobehavioral and neurobiological changes in male rats with pentylenetetrazol (PTZ)-induced epilepsy. Rats were assigned into five groups: (1) control rats, (2) RO-treated rats, (3) PTZ-treated rats, (4) PTZ + RO-treated rats, and (5) PTZ + valproic acid (VA)-treated rats. The PTZ-treated rats required a significantly longer time and distance to find the platform in the Morris water maze test than the control and RO-treated rats. Additionally, PTZ-treated rats showed a decrease in tendency to cross over the platform compared to PTZ group. PTZ + RO-treated rats showed decreased swimming time and distance to find the platform compared to PTZ group. PTZ + RO-treated rats showed a significant decrease in seizure score, a reduced number of myoclonic jerks, and an increased onset of the first myoclonic jerk compared to PTZ group. PTZ reduced the time required to enter the dark room in the passive avoidance learning test, which was reversed by RO treatment. Biochemical results revealed that PTZ-treated rats had higher levels of oxidative stress markers. RO significantly increased the antioxidant markers levels and maintained normal rat brain histology. This study revealed that RO can shield the brain and neural tissues from PTZ.
PubMed: 37888677
DOI: 10.3390/toxics11100826 -
Journal of Physiology and Pharmacology... Feb 2024This study was designed to examine the anti-oxidative stress effect of dimethyl fumarate (DMF) on pentylenetetrazole (PTZ)-induced epileptic mice, and to evaluate the...
This study was designed to examine the anti-oxidative stress effect of dimethyl fumarate (DMF) on pentylenetetrazole (PTZ)-induced epileptic mice, and to evaluate the correlation of its mechanism with the nuclear factor E2-related factor 2 (Nrf2)-mediated signaling pathway. The experimental mice were separated into three groups: control, model, and DMF groups. Mice in the model group were administered PTZ to establish an epilepsy model, mice in the DMF group were administered DMF concurrently when modeling, and mice in the control group were administered a 0.9% NaCl solution. The latency, severity, and frequency of epileptic seizures in mice after each treatment were recorded, and the modelling success rate was computed at the conclusion of the experiment. The mice were euthanized, their levels of malondialdehyde (MDA), reactive oxygen species (ROS), superoxide dismutase (SOD), 8-hydroxy-deoxyguanosine (8-OHdG), and Nrf2 were measured, and the electron microscope was used to examine the mitochondrial damage of brain tissue. The latency of epileptic seizures was longer in the DMF group compared to the model group (P<0.05). The levels of MDA and ROS in the DMF group were lower than those in the model group (P<0.0001), and the activity of SOD in the DMF group was higher than that in the model group (P<0.0001); however, the levels of MDA and ROS were elevated and the activity of SOD was lower in both groups relative to the control group. The levels of 8-OHdG were lower in the DMF group than the model group (P<0.0001), however, the levels were higher in both groups compared to the control group. Mitochondrial abnormalities were more prevalent in the model group than in the DMF group, and more prevalent in both groups compared to the control group. The DMF group contained more Nrf2 content than the model group (P<0.0001), and both groups contained more Nrf2 than the control group. We concluded that the mechanism by which DMF reduced the level of oxidative stress in epileptic mice might involve the Nrf2-mediated signaling pathway.
Topics: Animals; Mice; Antioxidants; Dimethyl Fumarate; Epilepsy; NF-E2-Related Factor 2; Oxidative Stress; Pentylenetetrazole; Reactive Oxygen Species; Seizures; Superoxide Dismutase
PubMed: 38583440
DOI: 10.26402/jpp.2024.1.07 -
Physiological Research May 2024Starting from simple clinical statistics, the spectrum of methods used in epilepsy research in the Institute of Physiology of the Czechoslovak (now Czech) Academy of...
Starting from simple clinical statistics, the spectrum of methods used in epilepsy research in the Institute of Physiology of the Czechoslovak (now Czech) Academy of Sciences progressively increased. Professor Servít used electrophysiological methods for study of brain activity in lower vertebrates, neuropathology was focused on electronmicroscopic study of cortical epileptic focus and ion-sensitive microelectrodes were used for studies of cortical direct current potentials. Developmental studies used electrophysiological methods (activity and projection of cortical epileptic foci, EEG under the influence of convulsant drugs, hippocampal, thalamic and cortical electrical stimulation for induction of epileptic afterdischarges and postictal period). Extensive pharmacological studies used seizures elicited by convulsant drugs (at first pentylenetetrazol but also other GABA antagonists as well as agonists of glutamate receptors). Motor performance and behavior were also studied during brain maturation. The last but not least molecular biology was included into the spectrum of methods. Many original data were published making a background of position of our laboratory in the first line of laboratories interested in brain development.
PubMed: 38752773
DOI: No ID Found -
Neurologia May 2024In the present study, anticonvulsant effects of aqueous extract (AE), hydro-alcoholic crude extract (HE), and its fractions (F-CHCl, F-EtOAc, F-MeOH) of Paeonia daurica...
INTRODUCTION
In the present study, anticonvulsant effects of aqueous extract (AE), hydro-alcoholic crude extract (HE), and its fractions (F-CHCl, F-EtOAc, F-MeOH) of Paeonia daurica subsp. macrophylla (P. daurica ssp. macrophylla) root examined by using a pentylenetetrazol-induced model (PTZ) on mice.
METHODS
HE and its fractions as well as AE, in concentrations of (100, 200 and 400mg/kg), valproate (Val) (100 and 200mg/kg), and saline (negative control) (10mg/kg) were injected intraperitoneally (i.p.) 30min before PTZ (80mg/kg, i.p.). The time taken before the onset of myoclonic convulsions (MC), MC duration, time taken before the onset of generalized tonic-clonic seizures (GTCS), the duration of GTCS, and the percentage of GTCS and mortality protection recorded. The plant's anticonvulsant mechanisms were assessed using flumazenil (5mg/kg, i.p.) before AE (100, 200, and 400mg/kg, i.p.) injection. GraphPad Prism software was used to compare the differences between various treatment groups with one-way analysis of variance (ANOVA) followed by Tukey-Krammer multiple comparison tests.
RESULTS
All the plant samples except F-EtOAc significantly delayed the onset and decreased the duration of PTZ-induced MCS and GTCS, and significantly reduced the GTCS and mortality rate. Pretreatment with flumazenil diminished the significant anticonvulsant effects of AE against PTZ-induced seizures.
CONCLUSIONS
It can report that extract of P. daurica ssp. macrophylla might be a helpful guide for future studies in the treatment of epilepsy.
Topics: Animals; Mice; Anticonvulsants; Pentylenetetrazole; Paeonia; Flumazenil; Seizures
PubMed: 38616060
DOI: 10.1016/j.nrleng.2021.08.004 -
Pharmaceuticals (Basel, Switzerland) May 2024Epilepsy is defined by an excessive level of activity in the neurons and coordinated bursts of electrical activity, resulting in the occurrence of seizure episodes. The...
BACKGROUND
Epilepsy is defined by an excessive level of activity in the neurons and coordinated bursts of electrical activity, resulting in the occurrence of seizure episodes. The precise cause of epileptogenesis remains uncertain; nevertheless, the etiology of epilepsy may involve neuroinflammation, oxidative stress, and malfunction of the neurotransmitter system.
OBJECTIVE
The goal of this investigation was to assess barbaloin's protective properties with respect to pentylenetetrazol (PTZ)-)-induced cognitive deficits in rats via antioxidative, anti-inflammatory, and neurotransmitter-modulating effects.
METHODS
rats were subjected to PTZ [40 mg/kg (i.p.)], which induced cognitive decline. Behavior assessment using a kindling score, open-field test (OFT), novel object recognition test (NORT), and assays for , and , and neurotransmitter levels [GABA, DA, NE, and serotonin (5-HT)] were performed.
RESULTS
The treatment of rats with barbaloin resulted in behavior improvement and significant changes in the levels of , and compared to the PTZ control group. Barbaloin treatment resulted in notable changes in neurotransmitter levels ) compared to the PTZ group.
CONCLUSIONS
The ongoing study has gathered evidence indicating that the injection of barbaloin has resulted in significant improvements in cognitive performance in rats. This is achieved by inhibiting oxidative stress, enhancing the activity of natural antioxidant enzymes, reducing cytokine levels, and increasing the levels of neurotransmitters in the brain. These results were detected in comparison to a PTZ control and can be attributed to the potent anti-inflammatory and antioxidant capabilities of barbaloin, which could be linked to its neuroprotective properties. Barbaloin may potentially increase cognitive decline and boost neuronal survival by altering the expression of
PubMed: 38931365
DOI: 10.3390/ph17060699 -
Frontiers in Neurology 2024Patients with Neurofibromatosis type 1 (NF1), the most common neurocutaneous disorder, can develop several neurological manifestations that include cognitive impairments...
INTRODUCTION
Patients with Neurofibromatosis type 1 (NF1), the most common neurocutaneous disorder, can develop several neurological manifestations that include cognitive impairments and epilepsy over their lifetime. It is unclear why certain patients with NF1 develop these conditions while others do not. Early-life immune activation promotes later-life seizure susceptibility, neurocognitive impairments, and leads to spontaneous seizures in some animal models of neurodevelopmental disorders, but the central nervous system immune profile and the enduring consequences of early-life immune activation on the developmental trajectory of the brain in NF1 have not yet been explored. We tested the hypothesis that early-life immune activation promotes the development of spatial memory impairments and epileptogenesis in a mouse model of NF1.
METHODS
Male wild-type (WT) and mice received systemic lipopolysaccharide (LPS) or saline at post-natal day 10 and were assessed in adulthood for learning and memory deficits in the Barnes maze and underwent EEG recordings to look for spontaneous epileptiform abnormalities and susceptibility to challenge with pentylenetetrazole (PTZ).
RESULTS
Whereas early-life immune activation by a single injection of LPS acutely elicited a comparable brain cytokine signature in WT and mice, it promoted spontaneous seizure activity in adulthood only in the mice. Early-life immune activation affected susceptibility to PTZ-induced seizures similarly in both WT and mice. There was no effect on spatial learning and memory regardless of mouse genotype.
DISCUSSION
Our findings suggest environmental events such as early-life immune activation may promote epileptogenesis in the mouse and may be a risk-factor for NF1-associated epilepsy.
PubMed: 38685949
DOI: 10.3389/fneur.2024.1284574 -
Frontiers in Pharmacology 2024Patients with mutations that alter the function of the sodium channel present with a range of clinical features, including mild to severe seizures, developmental delay,...
Patients with mutations that alter the function of the sodium channel present with a range of clinical features, including mild to severe seizures, developmental delay, intellectual disability, autism, feeding dysfunction, motor impairment, and hypotonia. In an effort to identify compounds that could be potentially beneficial in associated epilepsy, Atkin et al. conducted an screen which resulted in the identification of 90 compounds that effectively reduced sodium influx into the cells expressing the human R1872Q mutation. The top compounds that emerged from this screen included amitriptyline, carvedilol, and nilvadipine. In the current study, we evaluated the ability of these three compounds to increase resistance to 6 Hz or pentylenetetrazole (PTZ)-induced seizures in wild-type CF1 mice and in a mouse line expressing the human R1620L mutation. We also evaluated the effects of fenfluramine administration, which was recently associated with a 60%-90% decrease in seizure frequency in three patients with -associated epilepsy. While amitriptyline, carvedilol, and fenfluramine provided robust protection against induced seizures in CF1 mice, only carvedilol was able to significantly increase resistance to 6 Hz- and PTZ-induced seizures in RL/+ mutants. These results provide support for further evaluation of carvedilol as a potential treatment for patients with mutations.
PubMed: 38895634
DOI: 10.3389/fphar.2024.1397225 -
Biomedicine & Pharmacotherapy =... Jun 2024Brain apoptosis is one of the main causes of epileptogenesis. The antiapoptotic effect and potential mechanism of Q808, an innovative anticonvulsant chemical, have never...
Brain apoptosis is one of the main causes of epileptogenesis. The antiapoptotic effect and potential mechanism of Q808, an innovative anticonvulsant chemical, have never been reported. In this study, the seizure stage and latency to reach stage 2 of pentylenetetrazol (PTZ) seizure rat model treated with Q808 were investigated. The morphological change and neuronal apoptosis in the hippocampus were detected by hematoxylin and eosin (HE) and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining, respectively. The hippocampal transcriptomic changes were observed using RNA sequencing (RNA-seq). The expression levels of hub genes were verified by quantitative reverse-transcription PCR (qRT-PCR). Results revealed that Q808 could allay the seizure score and prolong the stage 2 latency in seizure rats. The morphological changes of neurons and the number of apoptotic cells in the DG area were diminished by Q808 treatment. RNA-seq analysis revealed eight hub genes, including Map2k3, Nfs1, Chchd4, Hdac6, Siglec5, Slc35d3, Entpd1, and LOC103690108, and nine hub pathways among the control, PTZ, and Q808 groups. Hub gene Nfs1 was involved in the hub pathway sulfur relay system, and Map2k3 was involved in the eight remaining hub pathways, including Amyotrophic lateral sclerosis, Cellular senescence, Fc epsilon RI signaling pathway, GnRH signaling pathway, Influenza A, Rap1 signaling pathway, TNF signaling pathway, and Toll-like receptor signaling pathway. qRT-PCR confirmed that the mRNA levels of these hub genes were consistent with the RNA-seq results. Our findings might contribute to further studies exploring the new apoptosis mechanism and actions of Q808.
Topics: Animals; Pentylenetetrazole; Hippocampus; Apoptosis; Anticonvulsants; Male; Transcriptome; Epilepsy; Gene Expression Profiling; Rats; Rats, Sprague-Dawley; Disease Models, Animal; Neurons; Seizures
PubMed: 38739991
DOI: 10.1016/j.biopha.2024.116746