Epileptic Seizures In Rats Research Articles

Effect of prednisolone in a kindling model of epileptic seizures in rats on cytokine and intestinal microbiota diversity

Epilepsy is a neurological disease characterized by spontaneous and recurrent seizures. Epileptic seizures can be initiated and facilitated by inflammatory mechanisms. As the dysregulation of the immune system would be involved in epileptogenesis, it is suggested that anti-inflammatory medications could impact epileptic seizures. These medications could potentially have a side effect by altering the structure and composition of the intestinal microbiota. These changes can disrupt microbial homeostasis, leading to dysbiosis and potentially exacerbating intestinal inflammation. We hypothesize that prednisolone may affect the development of epileptic seizures, potentially influencing the diversity of the intestinal microbiota and the regulation of pro-inflammatory cytokines in intestinal tissue. This study aimed to evaluate the effects of prednisolone treatment on epileptic seizures and investigate the effect of this drug on the bacterial diversity of the intestinal microbiota and markers of inflammatory processes in intestinal tissue. We used Male Wistar rat littermates (n = 31, 90-day-old) divided into four groups: positive control treated with 2 mg/kg of diazepam (n = 6), negative control treated with 0.9 g% sodium chloride (n = 6), and the remaining two groups were subjected to treatment with prednisolone, with one receiving 1 mg/kg (n = 9) and the other 5 mg/kg (n = 10). All administrations were performed intraperitoneally (i.p.) over 14 days. To induce the chronic model of epileptic seizures, we administered pentylenetetrazole (PTZ) 25 mg/kg i.p. on alternate days. Seizure latency (n = 6 – 10) and TNF-α and IL-1β concentrations from intestinal samples were measured by ELISA (n = 6 per group), and intestinal microbiota was evaluated with intergenic ribosomal RNA (rRNA) spacer (RISA) analysis (n = 6 per group). The prednisolone treatment demonstrated an increase in the latency time of epileptic seizures and TNF-α and IL-1β concentrations compared to controls. There was no statistically significant difference in intestinal microbiota diversity between the different treatments. However, there was a strong positive correlation between microbial diversity and TNF-α and IL-1β concentrations. The administration of prednisolone yields comparable results to diazepam on increasing latency between seizures, exhibiting promise for its use in clinical studies. Although there were no changes in intestinal microbial diversity, the increase in the TNF-α and IL-1β cytokines in intestinal tissue may be linked to immune system signaling pathways involving the intestinal microbiota. Additional research is necessary to unravel the intricacies of these pathways and to understand their implications for clinical practice.

Hydrogen treatment reduces electroencephalographic activity and neuronal death in rats with refractory status epilepticus by inhibiting membrane NR2B phosphorylation and oxidative stress.

To investigate the effects of hydrogen therapy on epileptic seizures in rats with refractory status epilepticus and the underlying mechanisms. Status epilepticus was induced using pilocarpine. The effects of hydrogen treatment on epilepsy severity in model rats were then monitored using Racine scores and electroencephalography (EEG), followed by western blot of plasma membrane N-methyl-D-aspartate receptor subtype 2B (NR2B) and phosphorylated NR2B expression. We also generated a cellular epilepsy model using Mg2+-free medium and used polymerase chain reaction to investigate the neuroprotective effects of hydrogen. There were no significant differences in Racine scores between the hydrogen and control groups. EEG amplitudes were lower in the hydrogen treatment group than in the control group. In epilepsy model rats, hippocampal cell membrane NR2B expression and phosphorylation increased gradually over time. Although hippocampal cell membrane NR2B expression was not significantly different between the two groups, NR2B phosphorylation levels were significantly lower in the hydrogen group. Hydrogen treatment also increased superoxide dismutase, mitochondrial (SOD2) expression. Hydrogen treatment reduced EEG amplitudes and NR2B phosphorylation; it also decreased neuronal death by reducing oxidative stress. Hydrogen may thus be a potential treatment for refractory status epilepticus by inhibiting membrane NR2B phosphorylation and oxidative stress.

Rats in Epilepsy Research: A Bibliometric Analysis of Citations Between 1969 and 2020 on Experimental Models in Epilepsy.

Epilepsy stands as a prominent neurological disorder, affecting a substantial number of individuals who, unfortunately, do not respond to conventional antiepileptic medications. To unravel the intricate mechanisms underlying epileptic seizures and explore potential therapeutic avenues, researchers have turned to animal models. Among these models, rats have emerged as one of the cornerstones of epilepsy research. This bibliometric analysis embarks on the crucial task of delving into the role of rat models in deciphering the mysteries of epileptic seizures and, notably, pinpointing the most prevalent models in use. Our study harnessed Scopus' citation tracking feature to review a range of research papers dating from 1969 to 2020, all dedicated to the exploration of epileptic seizures in rats. The citations that emerged from this rigorous process were subjected to thematic coding, primarily centered around the specific epileptic animal models employed, and subsequently, comprehensive descriptive statistics were computed. In this effort, we found a total of 1,318 publications that explore the world of rat studies, accumulating a substantial citation count of 44,824 references. This analysis illuminated the invaluable role that research employing rat models has played in shaping our current clinical understanding of epileptic seizures. Notably, several models have emerged as predominant forces in this field, including those induced by pilocarpine, pentylenetetrazole (PTZ), kainic acid (KA), electric kindling, and electroshock. This bibliometric exploration serves as a resounding reminder of the pivotal position that rat models occupy in advancing our comprehension of epilepsy. These findings resonate strongly, underscoring the continued importance of directing research and development funding toward this debilitating disorder, with the ultimate aim of maximizing the benefits for the patients grappling with this condition. The potential to revolutionize our approach to epilepsy and enhance the quality of life for those affected remains a beacon of hope, illuminated by the contributions of these tireless researchers and their trusty rat companions.

Neuroprotective Effect of Ruscogenin against Cognitive Impairment on Pentylenetetrazole-induced Epileptic Seizures in Rats

Neuroprotective Effect of Ruscogenin against Cognitive Impairment on Pentylenetetrazole-induced Epileptic Seizures in Rats

Administration of Curcumin plus Treadmill Exercise Modulate Some Neuronal Enzyme Activities, Redox Markers and BDNF mRNA Expression in Pilocarpine-Induced Epileptic Seizure in Rats

Administration of Curcumin plus Treadmill Exercise Modulate Some Neuronal Enzyme Activities, Redox Markers and BDNF mRNA Expression in Pilocarpine-Induced Epileptic Seizure in Rats

Finding Improved Protocols for Using Deep-Brain Stimulation for Treating Epileptic Seizures in Rats

Epilepsy, a neural disorder marked by seizures, affects millions of people and is a tremendous reason for distress in the lives of epileptic patients and their loved ones. There are many ways to treat epilepsy such as antiepileptic drugs (AEDs), surgery, and devices like the Vagus Nerve Stimulator. Regardless, the aforementioned methods of treatment are not efficient enough because they do not target the main source of the disorder. In order to target the main source, the natural dynamics of the brain that are effected by seizures need to be understood and this can be done by stimulating seizures in Sprague Dawley rats and analyzing their local field potentials during seizures and comparing the extracted data to real-time videos of the rats while having seizures for verification. Also, histological analysis will enhance this understanding. By doing this, the most effective frequency for the therapeutic stimulation can be found and this can be used to mitigate and, ideally, terminate seizures. This verification will be necessary to moveon to the future steps which entail the integration of the edited videos with electroencephalogram (EEG). The extracted data and real-time videos should correspond with the EEG. This will aid in the preparation for the next group of rat subjects.

Sestrin 3 promotes oxidative stress primarily in neurons following epileptic seizures in rats

Epilepsy affects approximately 1% of the global population, with 30% of patients experiencing uncontrolled seizures despite treatment. Reactive oxygen species (ROS) and oxidative stress have been implicated in the pathogenesis of epilepsy. Sestrins are stress-inducible proteins that regulate the ROS response. In particular, Sestrin 3 (SESN3) has been implicated in ROS accumulation and the regulation of proconvulsant genes. To investigate the role of SESN3 in epilepsy, we studied its involvement in rat models of acute seizures and temporal lobe epilepsy. Our results showed that downregulation of SESN3 reduced the oxidative stress induced by seizure activity in neuronal cultures. After acute seizure activity, SESN3 protein levels temporarily increased as early as 3 h after the seizure, whereas kainic acid-induced status epilepticus led to a significant and persistent increase in SESN3 protein levels in the cortex and hippocampus for up to 2 weeks post-status epilepticus. In the chronic epilepsy phase, when spontaneous seizures emerge, SESN3 protein expression is significantly increased in both regions 6 and 12 weeks after status epilepticus. Interestingly, immunohistochemical staining showed a predominant increase in the oxidative stress marker 8-OHdG in neurons in both regions after an acute seizure, whereas following status epilepticus, the marker was detected in both neurons and astrocytes. Our findings suggest that SESN3 may contribute to the development and establishment of epilepsy, and could be a potential therapeutic target for more effective treatments.

Downregulating NHE-1 decreases the apoptosis of hippocampal cells in epileptic model rats based on the NHE-1/calpain1 pathway

Seizure is associated with pathological changes of hippocampus, but the mechanism by which hippocampal neuronal apoptosis promotes epilepsy is unclear. Our previous study showed that the expression of NHE-1 was increased in epileptic model rats. Therefore, this study further explores the effect of NHE-1 on hippocampal cells apoptosis and seizure in lithium chloride-pilocarpine epileptic model rats. First, we established a lithium chloride-pilocarpine induced epileptic rat model and detected the expression of NHE-1, calpain1 and apoptosis in the hippocampus. Then, we further down-regulated NHE-1 to observe the expression of calpain1 and apoptosis in the hippocampus, as well as its effect on seizures in rats. We found that the expression of NHE-1 and calpain1 and apoptosis in the hippocampus was significant increased in the model group. After down-regulating NHE-1, the expression of calpain1 was decreased, and hippocampal cell apoptosis was alleviated. In addition, down-regulation of NHE-1 reduced the frequency and duration of seizures in epileptic rats. Therefore, hippocampal NHE-1 overexpression is closely related to the development of neuronal apoptosis in a rat model of epilepsy, and downregulating NHE-1 expression can reduce cell apoptosis. Moreover, the NHE-1/calpain1 signaling pathway may be an important mechanism leading to hippocampal cell apoptosis.

The Extract of Bombax Costatum Bark Improves Depression and Epileptic Seizures in Rats

Background: The plant Bombax costatum (BC) has been used traditionally in Nigeria for the management of various ailments. The chloroform extract of BC bark was investigated for its potential effects against the induced seizures and depression in rats. Methods: Thirty Wistar rats were divided into five groups of six. Group I received normal saline, group II received pentylenetetrazole (PTZ, 35 mg/kg), group III received diazepam (5 mg/kg) plus PTZ at 35 mg/kg, group IV received 250 mg/kg of the BC extract, and group V received 500 mg/kg of the same extract. The above protocol was repeated on alternate days from the first to twenty 5th days. Results: Tukey’s post hoc test revealed a statistically significant increase in the seizure scores after using PTZ (3.38±0.29, P<0.0001), in contrast to a decrease in the seizures after treatment with the BC extract (250 mg/kg; 2.72±0.25, P=0.0001). The analysis of variance for forced swimming test showed a significant decrease in immobility time if treatment with the extract (250 mg/kg; 125±5.59; P=0.01). The immobility duration increased with the PTZ treatment (163.8±12.03). The brain’s dopamine and serotonin levels under PTZ effect significantly decreased to 140.2±15.66 and 26.38±1.16, respectively, when the rats were treated with the extract at 500 mg/kg. Conclusion: The findings of this study suggest that the BC extract has anticonvulsive and anti-depressive properties, thus it offers neuro-protection against both conditions, induced by PTZ in rats.

Deep brain stimulation suppresses epileptic seizures in rats via inhibition of adenosine kinase and activation of adenosine A1 receptors.

Deep brain stimulation (DBS) of the anterior nucleus of the thalamus, is an effective therapy for patients with drug-resistant epilepsy, yet, its mechanism of action remains elusive. Adenosine kinase (ADK), a key negative regulator of adenosine, is a potential modulator of epileptogenesis. DBS has been shown to increase adenosine levels, which may suppress seizures via A1 receptors (A1 Rs). We investigated whether DBS could halt disease progression and the potential involvement of adenosine mechanisms. Control group, SE (status epilepticus) group, SE-DBS group, and SE-sham-DBS group were included in this study. One week after a pilocarpine-induced status epilepticus, rats in the SE-DBS group were treated with DBS for 4 weeks. The rats were monitored by video-EEG. ADK and A1 Rs were tested with histochemistry and western blot, respectively. Compared with the SE group and SE-sham-DBS group, DBS could reduce the frequency of spontaneous recurrent seizures (SRS) and the number of interictal epileptic discharges. The DPCPX, an A1 R antagonist, reversed the effect of DBS on interictal epileptic discharges. In addition, DBS inhibited the overexpression of ADK and the downregulation of A1 Rs. The findings indicate that DBS can reduce SRS in epileptic rats via inhibition of ADK and activation of A1 Rs. A1 Rs might be a potential target of DBS for the treatment of epilepsy.

Nrf2 is expressed more extensively in neurons than in astrocytes following an acute epileptic seizure in rats.

The modulation of the nuclear factor erythroid 2-like 2 (Nrf2) activity has been reported to be implicated in the pathology of various neurological disorders, including epilepsy. Previous studies have demonstrated that Nrf2 is activated in the post-status epilepticus rat model; however, the spatiotemporal as well as cell type-specific expression of Nrf2 following brief epileptic seizures remains unclear. Here, we evaluated how an acute epileptic seizure affected the expression of Nrf2 and its downstream genes in the rats' cortex and the hippocampus up to 1 week following the induced seizure. We found that after a pentylenetetrazol-induced seizure, Nrf2 significantly increased at 24 h at the mRNA level and 3h at the protein level in the cortex. In the hippocampus, the Nrf2 mRNA level peaked at 3h after the seizure, and no significant changes were observed in the protein level. Interestingly, the mRNA level of Nrf2 downstream genes peaked at 3-6h after seizure in both the cortex and the hippocampus. A significant increase in the expression of Nrf2 was observed in the neuronal population of CA1 and CA3 regions of the hippocampus, as well as in the cortex. Moreover, we observed no change in the co-localization of Nrf2 with astrocytes neither in the cortex nor in CA1 and CA3. Our results revealed that following a brief acute epileptic seizure, the expression of Nrf2 and its downstream genes is transiently increased and peaked at early timepoints after the seizure predominantly in the hippocampus, and this expression is restricted to the neuronal population.

Molecular docking to investigate the inhibitory activity and the role of nitric oxide in anticonvulsant effects of vitamin D on pentylenetetrazole‑induced epileptic seizures in rats

Despite the great breakthroughs in the field of epilepsy studies, the present drugs are ineffective in one-third of the patients, as well as without providing a definite treatment. There is accumulating evidence suggesting the role of vitamin D in epilepsy. The aim of this study was to investigate the effect of vitamin D on seizure formation, post-seizure cognitive functions, and the possible role of nitric oxide and oxidative stress in this effect, in the PTZ-induced seizure rat model. Sixty male Wistar albino rats were used in this study. The rats were randomly divided into 11 groups each containing 6 animals: Group 1: Control; Group 2: Saline+PTZ (45 mg/kg); Group 3: Vitamin D (1.5 mg/kg)+PTZ; Group 4: L-Arginine (500 mg/kg)+PTZ; Group 5: L-NAME (60 mg/kg)+PTZ; Group 6: 7-Nitroindazole (40 mg/kg); Group 7: Aminoguanidine (100 mg/kg)+PTZ; Group 8: Vitamin D+L- Arginine+PTZ; Group 9: Vitamin D+L-NAME+PTZ; Group 10: Vitamin D+7-Nitroindazole+PTZ; Group 11: Vitamin D+Aminoguanidine+PTZ. Animal behavior was evaluated with open field and passive avoidance tests. Nitric oxide (NO), total oxidative status (TOS), and total antioxidant status (TAS) levels in the cortex and hippocampus brain regions were determined by ELISA method. The treatment of vitamin D in combination with NO inhibitors has a positive effect on the PTZ-induced seizures and ameliorate post-seizure learning deficits. Moreover, the combination of vitamin D with NO inhibitors reduced oxidative stress and NO levels after seizures in the cortex and hippocampus. Also, we employed molecular docking and density functional theory analysis to investigate the inhibitory activity, reactivity, and stability of Vitamin D with other NO inhibitors. Vitamin D supplementation could be effective as a supportive treatment drug in epileptic patients, according to the findings.

Evaluation of the Protective Effect of The Cup Therapy on the Epileptic Seizure in Rats

Objective: Cup therapy has an important place in traditional and complementary medicine applications. The purpose of our study, this is the first time to investigate the protective effect of cup therapy in rats on experimentally generated epileptic seizures in new rat modeling created by different anatomic regions.
 Methods: In our study, 42 Wistar albino rats 3-4 months old (200-250 g) were used. Four other groups (n=7) except G3 and G4, 24 hours after cup therapy application, PTZ (35 mg/kg, sc., 0.2 cc) was injected, followed by behavioral epilepsy scoring.
 Results: In the 'Open Area' and 'Elevated Plus Maze' tests, there was no behavioral difference between the cup therapy group and the control group (p > 0.05). Given all the parameters, the G4 group significantly reduces the seizure compared to other groups (p < 0.05). There is a significant difference in G2, G5 and G6 groups compared to G3 in the phases parameter (p < 0.05).
 Conclusions: In this study, the new wet cup therapy (G2), which was applied for the first time, had a protective effect on seizures. G2, G5 and G6 groups are observed to suppress seizures compared to G3. Our findings are expected to contribute greatly to animal model analysis in the future.

Protective effect of Wuling mycelia, alone and in combination with valproic acid, on pentylenetetrazolinduced epilepsy in rats

Purpose: To determine the inhibitory effects of Wuling mycelia, alone and in combination with valproic acid (VPA) on pentylenetetrazol (PTZ)-induced epileptic seizure in rats, and their protective effects on cognitive impairment.Methods: Sprague-Dawley rats were randomly divided into five groups: control (sham), model, Wuling mycelia, VPA and combination groups. Rats in Wuling mycelia group were given oral Wuling mycelia alone at a dose of 594 mg/kg, while those in VPA group were given oral VPA alone at a dose of 189 mg/kg. In the combination group, rats received oral VPA at a dose of 189 mg/kg co-administered with Wuling mycelia at a dose of 594 mg/kg. One hour after the treatments, the control group was injected with physiological saline intraperitoneally, while the other four groups were injected with PTZ solution once a day for 28 days. Subsequently, seizure intensity, cognitive impairment, neuronal loss and hippocampal expressions of IL-1β, NF-ĸB/p65 and TLR4 were determine in all groups.Results: Combined use of Wuling mycelium and VPA significantly reduced the frequency and the grade of seizures (p <0.01), and also decreased the degree of cognitive impairment (p <0.05). There were marked increases in neuronal damage and hippocampal expression levels of NF-ĸB/p65, TLR4 and IL1β (inflammatory cytokines) in the model group (p < 0.05). However, these changes were reversed in the combination treatment group (p < 0.05).Conclusion: Wuling mycelia is a potentially effective adjunct drug for the treatment of refractory epilepsy. The underlying mechanism might involve downregulations of NF-ĸB/p65, TLR4 and IL-1β.
 Keywords: Wuling mycelia, Refractory epilepsy, Seizure, Traditional Chinese medicine, Hippocampal area, HMGB1/TLR4/NF-κB signalling pathway, IL-1β, NF-ĸB/p65, TLR4

Mast cell activation ameliorates pentylenetetrazole-induced seizures in rats: The potential role for serotonin.

Neuroinflammation plays a key role in the pathogenesis of epilepsy, but the underlying mechanisms are not well understood. Mast cells are multifunctional immune cells that are also activated by stress. The effects of activated mast cells on epileptogenesis are not yet known. This study investigated the effects and mechanisms of compound 48/80-stimulated mast cell activation on pentylenetetrazole-induced epileptic seizures in rats. Male Wistar rats were separated into seven groups (n=12). Group-1(NS+PTZ) received intraperitoneal saline solution, while groups 2(C-48/80+PTZ-1), 3(C-48/80+PTZ-2), and 4(C-48/80+PTZ-3) received compound-48/80 at doses of 0.5, 1, and 2mg/kg, respectively, 30min before 45mg/kg pentylenetetrazole administration. Similarly, Group-5(Cr+C-48/80+PTZ) received 10mg/kg cromolyn plus 2mg/kg compound-48/80 before pentylenetetrazole, and Group-6(MC Dep+C-48/80+PTZ) was exposed to a mast cell-depletion process, and then received 2mg/kg compound-48/80. Group-7(5-HT+PTZ) received 10mg/kg serotonin. Seizure stages were evaluated using Racine's scale. Compound-48/80 at 2mg/kg induced anticonvulsive effects against pentylenetetrazole-induced seizures by extending onset-times of both myoclonic-jerk and generalized tonic-clonic seizures (p=0.0001), and by shortening the duration of generalized tonic-clonic seizure (p=0.008). These effects were reversed by cromolyn (p=0.0001). These effects were not observed in mast cell-depleted rats. Similarly to compound 48/80, serotonin also exhibited anticonvulsive effects against seizures (p<0.05). Compound 48/80 acts as an anticonvulsant by activating mast cells in a dose-dependent manner. The anticonvulsive effects of mast cell activation may be mediated by serotonin. Mast cell activation may therefore provide protective activity against seizures under appropriate circumstances.

The role of nitric oxide in anticonvulsant effects of lycopene supplementation on pentylenetetrazole-induced epileptic seizures in rats.

Recent studies have shown that natural antioxidant compounds have positive effects on the nervous system. Lycopene, the red pigment in tomatoes, is one of the potent natural antioxidants, and is used as supplementation because of its well-known health benefits. However, its effect on epileptic seizures and underlying mechanisms are still unclear. In this study, it was aimed to investigate the effect of lycopene on pentylenetetrazole-induced epileptic seizures in rats and to elucidate the nitric oxide pathway in this effect. In this study, thirty male Wistar albino rats were used. Animals were divided into five groups (n = 6 for each group) as control, saline (1mL/kg/day serum physiologic), positive control (2mg/kg/day diazepam), and lycopene (5 and 10mg/kg/day) for ten days. Pentylenetetrazole (45mg/kg) was given to induce a seizure in the tenth day except for the control. Passive avoidance test was carried out to evaluate memory function. Inducible nitric oxide synthase (iNOS), neuronal nitric oxide synthase (nNOS), and nitric oxide (NO) levels were measured in the cortex and hippocampal brain regions using the ELISA kits. Lycopene supplementation prolonged epileptic seizure onset times and reduced seizure stages. Besides, lycopene supplementation improved memory impairment after seizures. Moreover, lycopene significantly reduced the level of iNOS, nNOS, and NO in the brain. Lycopene supplementation significantly alleviated seizures and memory impairment. Its anticonvulsive effect could be associated with the nitric oxide pathway. Lycopene supplementation could be useful as a supportive therapeutic agent in epileptic patients.

The Effects of Proton Pump Inhibitors (Pantoprazole) on Pentylenetetrazole-Induced Epileptic Seizures in Rats and Neurotoxicity in the SH-SY5Y Human Neuroblastoma Cell Line.

Recent studies have shown that proton pump inhibitors have positive effects on the nervous system. However, its effect on epileptic seizure and neuronal damage are still unclear. In this study, it was aimed to investigate the effect of pantoprazole on pentylenetetrazole-induced epileptic seizures in rats and neurotoxicity in the SH-SY5Y cell line. Animals were divided into three groups: control, saline (1mL/kg serum physiologic), and pantoprazole (10mg/kg). Pentylenetetrazole (45mg/kg) was given to induce a seizure and a passive avoidance test trial was carried out to evaluate memory function. 8-hydroxy-2'-deoxyguanosine (8-OHdG), caspase-3, and brain-derived neurotrophic factor (BDNF) levels were measured in the brain by commercial kits. SH-SY5Y cells were treated with saline or pantoprazole for one hour, and then pentylenetetrazole (30µm) was added to the medium to induce neurotoxicity. After 24h, cell viability, total antioxidant, total oxidant status, and apoptosis were measured in SH-SY5Y cells. It was found that pantoprazole treatment postponed epileptic seizure onset, protected memory, reduced 8-OHdG, caspase-3, and also increased BDNF in the brain. In addition, it blocked pentylenetetrazole toxicity, apoptosis, increased antioxidant, and decreased oxidant status in SH-SY5Y cells. Pantoprazole significantly improved seizure, oxidative stress, and apoptosis. Thus, pantoprazole could be used as a supportive therapeutic agent in epilepsy.

A Potent Lignan from Prunes Alleviates Inflammation and Oxidative Stress in Lithium/Pilocarpine-Induced Epileptic Seizures in Rats.

Prunus domestica L. is an edible plant that is included in the family Rosaceae and proven to possess potent anti-inflammatory and anxiolytic activity. Pinoresinol-4-O-β-d-glucopyranoside (PGu) was isolated from Prunus domestica methanol extract and its structure was determined using 1-D and 2-D NMR (one- and two-dimensional nuclear magnetic resonance). PGu was evaluated for its anticonvulsant activity using lithium/pilocarpine-induced epileptic seizures in rats. PGu displayed a notable antioxidant and anti-inflammatory activity in vitro. It ameliorates the seizures triggered by pilocarpine in a dose-dependent manner, manifested by retarding seizure onset, reducing the number of rats developing seizures, and enhancing the survival of animals after seizure exposure. PGu reduced MDA (malondialdehyde) level by 24.2% in addition to increasing catalase activity by 44.4% at 50 mg/kg b.w compared to pilocarpine-treated animals. This was confirmed by histopathological examination in which pretreatment with PGu (50 mg/kg b.w.) attenuated neurodegeneration and seizures with no histopathological alteration in neurons of the cerebral cortex. In the immunohistochemical examination, it significantly declined the elevated Cyclooxygenase-2 (COX-2) by 40% and decreased Inducible nitric oxide synthase (iNOS) expression by 18% as expressed by the optical density. PGu revealed a pronounced fitting within the active site of 5-LOX (lipoxygenase-5) with a free binding energy (∆G) equals to −65.05 kcal/mol. PGu could perfectly serve as a potent lead drug for the relief of epileptic seizures, which appeals to many patients owing to its natural origin.

Deep brain stimulation reduces evoked potentials with a dual time course in freely moving rats: Potential neurophysiological basis for intermittent as an alternative to continuous stimulation.

Deep brain stimulation (DBS) is an increasingly applied treatment for various neuropsychiatric disorders including drug-resistant epilepsy, and it may be optimized by rationalizing the stimulation protocol based on increased knowledge of its mechanism of action. We evaluated the effects of minutes to hours of hippocampal DBS on hippocampal evoked potentials (EPs) and local field potentials (LFPs) in freely moving male rats to further investigate some of the previously proposed mechanisms of action. Hippocampal high-frequency (130Hz) DBS was administered for 0, 1, or 6min every 10min for 160min. Stimulation parameter settings were similar to those that had previously been shown to reduce seizures in epileptic rats. EPs and LFPs were recorded in the stimulation-free intervals. We investigated both the immediate temporary effects of 1 or 6min of DBS and the effects of 160min of intermittent DBS. Input specificity was investigated by using two different stimulation electrodes. Relatively low DBS intensities corresponding to only 1.8% of the intensity evoking a maximum EP were required to prevent unintended seizure occurrence in healthy rats. Both 1 and 6min of DBS caused input-specific short-lasting (<60 s) reductions (5%-7%) of the field excitatory postsynaptic potential (fEPSP) slope (P=.005). We observed longer-lasting, input-specific EP reductions during the 160min intermittent DBS, with statistically significant reductions (3%-4%) of the fEPSP slope (P=.009-.018). The LFP spectrogram remained unaltered. Deep brain stimulation induced both acute temporary effects compatible with axonal block and/or synaptic depression, and longer-lasting potentially cumulative EP reductions, suggesting the involvement of homeostatic plasticity or long-term depression. This dual time course may parallel the different temporal patterns of improvement observed in clinical trials. The longer-lasting reductions provide a potential neurophysiological basis for the use of intermittent DBS-as typically used in epilepsy patients-as an alternative to continuous DBS.

Oestrogen receptor ERα and ERβ agonists ameliorate oxidative brain injury and improve memory dysfunction in rats with an epileptic seizure.

What is the central question of this study? Could different hormonally active substances, including oestrogen receptor (ER) agonists, protect against oxidative brain damage and memory impairment induced by a single epileptic seizure in rats? If so, which signalling mechanisms are involved in their anti-inflammatory effects? What is the main finding and its importance? Chronic administration of oestrogen, progesterone, ER modulators/agonists or blockade of testosterone exhibited anti-inflammatory and antioxidant actions on single seizure-induced neuronal injury, while ER agonists additionally improved memory function and up-regulated CREB signalling and hippocampal GABA(A)α1 receptor density, suggesting that ERα or ERβ receptor activation may be beneficial in protecting against seizure-related oxidative brain injury and cognitive dysfunction. The susceptibility to epileptic seizures is dependent on sex as well as fluctuations in oestrogen levels, while exogenous oestrogen was shown to have no effect or to facilitate or to inhibit seizure activity. Oestrogen receptors (ERs) mediate antioxidant and anti-inflammatory actions in several inflammatory models, but the involvement of ERs in seizure-induced neuronal injury has not been evaluated previously. In order to assess the effects of resveratrol, progesterone, oestradiol (E2), an anti-testosterone (cyproterone acetate; CPA), a selective ER modulator (tamoxifen; TMX) and ERα/ERβ agonists (propyl pyrazole triol (PPT), diarylpropionitrile (DPN)) on oxidative brain damage and memory impairment due to epileptic seizure, male Wistar rats (n=120) received one of the treatment choices either in drinking water or intraperitoneally for 31 days, and epileptic seizure was induced on the 28th day by injection of a single-dose of pentylenetetrazole (45mgkg-1 ). The results demonstrate that chronic pretreatment with resveratrol, progesterone, E2, CPA or TMX suppressed most of the inflammatory parameters indicative of oxidative neuronal injury, while treatment with the ER agonists DPN or PPT were found to be even more effective in limiting the oxidative damage. Treatment with DPN resulted in the up-regulation of cAMP response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) expression, while PPT up-regulated expression of CREB without affecting BDNF levels. Moreover, both ER agonists provided protection against seizure-induced memory loss with a concomitant increase in hippocampal GABA(A)α1-positive cells. In conclusion, ER agonists, and more specifically ERβ agonist, appear to provide maximum protection against seizure-induced oxidative brain injury and associated memory dysfunction by up-regulating the expression of CREB, BDNF and GABA(A)α1 receptors.