Model Of Chronic Epilepsy Research Articles

Preliminary evaluation of accelerated microscopic diffusional kurtosis imaging (μDKI) in a rodent model of epilepsy

PurposeOur study aimed to develop accelerated microscopic diffusional kurtosis imaging (μDKI) and preliminarily evaluated it in a rodent model of chronic epilepsy. MethodsWe investigated two μDKI acceleration schemes of reduced sampling density and angular range in a phantom and wild-type rats, and further tested μDKI method in pilocarpine-induced epilepsy rats using a 4.7 Tesla MRI. Single slice average μDapp and μKapp maps were derived, and Nissl staining was obtained. ResultsThe kurtosis maps from two accelerated μDKI sampling schemes (sampling density and range) are very similar to that using fully sampled data (SSIM > 0.95). For the epileptic models, μDKI showed noticeably different contrast from those obtained with conventional DKI. Specifically, the average μKapp was significantly less than that of the average of Kapp (0.15 ± 0.01 vs. 0.47 ± 0.02) in the ventricle. ConclusionsOur study demonstrated the feasibility of accelerated in vivo μDKI. Our work revealed that μDKI provides complementary information to conventional DKI method, suggesting that advanced DKI sequences are promising to elucidate tissue microstructure in neurological diseases.

Chemical biomarkers of epileptogenesis and ictogenesis in experimental epilepsy

Epilepsy produces chronic chemical changes induced by altered cellular structures, and acute ones produced by conditions leading into individual seizures. Here, we aim to quantify 24 molecules simultaneously at baseline and during periods of lowered seizure threshold in rats. Using serial hippocampal microdialysis collections starting two weeks after the pilocarpine-induced status epilepticus, we evaluated how this chronic epilepsy model affects molecule levels and their interactions. Then, we quantified the changes occurring when the brain moves into a pro-seizure state using a novel model of physiological ictogenesis. Compared with controls, pilocarpine animals had significantly decreased baseline levels of adenosine, homovanillic acid, and serotonin, but significantly increased levels of choline, glutamate, phenylalanine, and tyrosine. Step-wise linear regression identified that choline, homovanillic acid, adenosine, and serotonin are the most important features to characterize the difference in the extracellular milieu between pilocarpine and control animals. When increasing the hippocampal seizure risk, the concentrations of normetanephrine, serine, aspartate, and 5-hydroxyindoleacetic acid were the most prominent; however, there were no specific, consistent changes prior to individual seizures.

Oral administration of the casein kinase 2 inhibitor TBB leads to persistent KCa2.2 channel up-regulation in the epileptic CA1 area and cortex, but lacks anti-seizure efficacy in the pilocarpine epilepsy model

Temporal lobe epilepsy (TLE) is the most common epileptic syndrome in adults and often presents with seizures that prove intractable with currently available anticonvulsants. Thus, there is still a need for new anti-seizure drugs in this condition. Recently, we found that the casein kinase 2 inhibitor 4,5,6,7-tetrabromotriazole (TBB) prevented the emergence of spontaneous epileptic discharges in an acute in vitro epilepsy model. This prompted us to study the anti-seizure effects of TBB in the pilocarpine model of chronic epilepsy in vivo. To this end, we performed long-term video-EEG monitoring lasting 78–167 days of nine chronically epileptic rats and obtained a baseline seizure rate of 3.3 ± 1.3 per day (baseline of 27–80 days). We found a significant age effect with more pronounced seizure rates in older animals as compared to younger ones. However, the seizure rate increased to 6.3 ± 2.2 per day during the oral TBB administration (treatment period of 21–50 days), and following discontinuation of TBB, this rate remained stable with 5.2 ± 1.4 seizures per day (follow-up of 30–55 days). After completing the video-EEG during the follow-up the hippocampal tissue was prepared and studied for the expression of the Ca2+-activated K+ channel KCa2.2. We found a significant up-regulation of KCa2.2 in the epileptic CA1 region and in the neocortex, but in no other hippocampal subfield. Hence, our findings indicate that oral administration of TBB leads to persistent up-regulation of KCa2.2 in the epileptic CA1 subfield and in the neocortex, but lacks anti-seizure efficacy in the pilocarpine epilepsy model.

M-Calpain Activation Facilitates Seizure Induced KCC2 Down Regulation.

Potassium chloride co-transporter 2 (KCC2), a major chloride transporter that maintains GABAA receptor inhibition in mature mammalian neurons, is down-regulated in the hippocampus during epileptogenesis. Impaired KCC2 function accelerates or facilitates seizure onset. Calpain, with two main subtypes of m- and μ-calpain, is a Ca2+-dependent cysteine protease that mediates the nonlysosomal degradation of KCC2. Although recent studies have demonstrated that calpain inhibitors exert antiepileptic and neuroprotective effects in animal models of acute and chronic epilepsy, whether calpain activation affects seizure induction through KCC2 degradation remains unknown. Our results showed that: (1) Blockade of calpain by non-selective calpain inhibitor MDL-28170 prevented convulsant stimulation induced KCC2 downregulation, and reduced the incidence and the severity of pentylenetetrazole (PTZ) induced seizures. (2) m-calpain, but not μ-calpain, inhibitor mimicked MDL-28170 effect on preventing KCC2 downregulation. (3) Phosphorylation of m-calpain has been significantly enhanced during seizure onset, which was partly mediated by the calcium independent MAPK/ERK signaling pathway activation. (4) MAPK/ERK signaling blockade also had similar effect as total calpain blockade on both KCC2 downregulation and animal seizure induction. The results indicate that upregulated m-calpain activation by MAPK/ERK during convulsant stimulation down regulates both cytoplasm- and membrane KCC2, and in turn facilitates seizure induction. This finding may provide a foundation for the development of highly effective antiepileptic drugs targeting of m-calpain.

Upregulation of klotho and erythropoietin contributes to the neuroprotection induced by curcumin-loaded nanoparticles in experimental model of chronic epilepsy

Klotho, which is a life extension factor, and erythropoietin (EPO) have been introduced as effective neuroprotective factors in several neurological disorders. The present study is an attempt to examine the potential role of klotho and EPO in therapeutic effect of curcumin-loaded nanoparticles (NPs) in pentylenetetrazol (PTZ)-induced kindling model. In order to induce the kindling model, PTZ was administrated intraperitoneally (i.p.) at dose of 36.5 mg/kg every other day for 20 days. Male NMRI mice received pre-treatment of free curcumin or curcumin-loaded NPs (12.5 mg/kg, i.p.) 10 days before PTZ injection and this was continued until 1 h before each PTZ injection. Immunostaining against NeuN, as a marker of neuronal maturation, and EPO was performed on hippocampal brain sections. Quantitative real time polymerase chain reaction (qRT-PCR) was conducted to assess the expression levels of tumor necrosis factor-α (TNF-α), klotho and EPO in the hippocampus. Immunostaining data indicated that treatment with curcumin-loaded NPs significantly alleviates the neuronal cell death in PTZ receiving animals. Curcumin-loaded NPs effectively upregulated the levels of EPO and klotho in PTZ receiving animals. Furthermore, mRNA level of TNF-α was considerably reduced in animals undergone curcumin-loaded NPs treatment. Overall, the results of this study suggest that downregulation of TNF-α and consequent upregulation of klotho and EPO might contribute to the neuroprotective effect of curcumin-loaded NPs in experimental model of epilepsy.

Evaluation of ghrelin, nesfatin-1 and irisin levels of serum and brain after acute or chronic pentylenetetrazole administrations in rats using sodium valproate

ABSTRACTObjectives: In this study, we aim to reveal the alterations (due to seizure) in the serum and brain levels of nesfatin-1, ghrelin and irisin after acute or chronic pentylenetetrazole administrations in rats using sodium valproate.Methods: 35 Wistar albino rats were randomly divided into five groups: Control, Acute Pentylenetetrazole group (APTZ), Acute Pentylenetetrazole+ Valproate group (AVPA), PTZ kindling group (PTZk) and PTZ kindling+ Valproate group (KVPA). Serum and brain levels of ghrelin, nesfatin-1 and FNDC5/irisin were determined with ELISA.Results: Serum levels of ghrelin were significantly decreased in APTZ and PTZk groups compared to the control (p < 0.01). There was a statistically significant decrease in brain levels of ghrelin in all groups compared to the control group (p < 0.01). There was a statistically significant increase in serum nesfatin-1 levels in the APTZ and PTZk groups compared to the control (p < 0.05). Serum levels of nesfatin-1 were similar to the control group in both the acute and the chronic treatment groups. There was a statistically significant increase in brain nesfatin-1 levels of the KVPA group compared to the control (p < 0.05). Serum and brain levels of FNDC5/irisin were found significantly increased in APTZ, AVPA and PTZk groups compared to the control (p < 0.01).Conclusions: Statistically significant alterations were detected in the serum and brain levels of these three peptides in both the PTZ-induced chronic epilepsy model and acute seizure model. The results of this study may suggest that the increase in FNDC5/irisin and nesfatin-1 levels, and the decrease in ghrelin levels may contribute to seizure pathophysiology. However, further studies are needed in order to confirm our hypothesis.

The novel, catalytic mTORC1/2 inhibitor PQR620 and the PI3K/mTORC1/2 inhibitor PQR530 effectively cross the blood-brain barrier and increase seizure threshold in a mouse model of chronic epilepsy

The mTOR signaling pathway has emerged as a possible therapeutic target for epilepsy. Clinical trials have shown that mTOR inhibitors such as everolimus reduce seizures in tuberous sclerosis complex patients with intractable epilepsy. Furthermore, accumulating preclinical data suggest that mTOR inhibitors may have anti-seizure or anti-epileptogenic actions in other types of epilepsy. However, the chronic use of rapalogs such as everolimus is limited by poor tolerability, particularly by immunosuppression, poor brain penetration and induction of feedback loops which might contribute to their limited therapeutic efficacy. Here we describe two novel, brain-permeable and well tolerated small molecule 1,3,5-triazine derivatives, the catalytic mTORC1/C2 inhibitor PQR620 and the dual pan-PI3K/mTOR inhibitor PQR530. These derivatives were compared with the mTORC1 inhibitors rapamycin and everolimus as well as the anti-seizure drugs phenobarbital and levetiracetam. The anti-seizure potential of these compounds was determined by evaluating the electroconvulsive seizure threshold in normal and epileptic mice. Rapamycin and everolimus only poorly penetrated into the brain (brain:plasma ratio 0.0057 for rapamycin and 0.016 for everolimus). In contrast, the novel compounds rapidly entered the brain, reaching brain:plasma ratios of ∼1.6. Furthermore, they significantly decreased phosphorylation of S6 ribosomal protein in the hippocampus of normal and epileptic mice, demonstrating effective mTOR inhibition. PQR620 and PQR530 significantly increased seizure threshold at tolerable doses. The effect of PQR620 was more marked in epileptic vs. nonepileptic mice, matching the efficacy of levetiracetam. Overall, the novel compounds described here have the potential to overcome the disadvantages of rapalogs for treatment of epilepsy and mTORopathies directly connected to mutations in the mTOR signaling cascade.

Changes in synaptic AMPA receptor concentration and composition in chronic temporal lobe epilepsy

Excitotoxicity caused by excessive stimulation of glutamate receptors, resulting in pathologically increased Ca2+-concentrations, is a decisive factor in neurodegenerative diseases. We investigated long-term changes in synaptic contents of AMPA receptor subunits that play important roles in calcium regulation in chronic epilepsy. Such plastic changes may be either adaptive or detrimental. We used a kainic acid (KA)-based rat model of chronic temporal lobe epilepsy (TLE). Using hippocampal synaptosomes, we found significant reductions in the concentration of the AMPA receptor subunits GluA1 and GluA2, and the NMDA receptor subunit NR2B. The relative size of GluA1 and GluA2 reductions were almost identical, at 28% and 27%, respectively. In order to determine whether the synaptic reduction of the AMPA receptor subunits actually reflected the pool of receptors present along the postsynaptic density (PSD), as opposed to cytoplasmic or extrasynaptic pools, we performed postembedding immunogold electron microscopy (EM) of GluA1 and GluA2 in Schaffer collateral synapses in the hippocampal CA1 area. We found significant reductions, at 32% and 52% of GluA1 and GluA2 subunits, respectively, along the PSD, indicating that these synapses undergo lasting changes in glutamatergic neurotransmission during chronic TLE. When compared to the overall concentration and composition of AMPA receptors expressed in the brain, there was a relative increase in GluA2-lacking AMPA receptor subunits following chronic epilepsy. These changes in synaptic AMPA receptor subunits may possibly contribute to further aggravate the excitotoxic vulnerability of the neurons as well as have significant implications for hippocampal cognitive functions.

Kainate Receptors: Role in Epilepsy.

Kainate (KA) is a potent neurotoxin that has been widely used experimentally to induce acute brain seizures and, after repetitive treatments, as a chronic model of temporal lobe epilepsy (TLE), with similar features to those observed in human patients with TLE. However, whether KA activates KA receptors (KARs) as an agonist to mediate the induction of acute seizures and/or the chronic phase of epilepsy, or whether epileptogenic effects of the neurotoxin are indirect and/or mediated by other types of receptors, has yet to be satisfactorily elucidated. Positing a direct involvement of KARs in acute seizures induction, as well as a direct pathophysiological role of KARs in the chronic phase of TLE, recent studies have examined the specific subunit compositions of KARs that might underly epileptogenesis. In the present mini-review, we discuss the use of KA as a convulsant in the experimental models of acute seizures of TLE, and consider the involvement of KARs, their subunit composition and the mode of action in KAR-mediated epilepsy. In acute models, evidence points to epileptogenesis being precipitated by an overall depression of interneuron GABAergic transmission mediated by GluK1 containing KARs. On glutamatergic principal cell in the hippocampus, GluK2-containing KARs regulate post-synaptic excitability and susceptibility to KA-mediated epileptogenesis. In chronic models, a role GluK2-containing KARs in the hippocampal CA3 region provokes limbic seizures. Also observed in the hippocampus, is a ‘reactive plasticity’, where MF sprouting is seen with target granule cells at aberrant synapses recruiting de novo GluR2/GluR5 heteromeric KARs. Finally, in human epilepsy and animal models, astrocytic expression of GluK1, 2, 4, and 5 is reported.

Curcumin in epilepsy disorders.

Curcumin, a principal curcuminoid present in turmeric, has an antioxidant, anti-inflammatory and neuroprotective properties. Preclinical studies have indicated its beneficial effect for the treatment of epilepsy disorders. The molecule has an anti-seizure potential in preclinical studies, including chemical and electrical models of acute and chronic epilepsy. Curcumin also possesses an anti-epileptogenic activity as it reduces spontaneous recurrent seizures severity in a kainate model of temporal lobe epilepsy. The antioxidant and anti-inflammatory nature of curcumin might be responsible for its observed anti-seizure effects; nevertheless, the exact mechanism is not yet clear. The poor availability of curcumin to the brain limits its use in clinics. The application of nanoliposome and liposome technologies has been tested to enhance its brain availability and penetrability. Unfortunately, there are no randomized, double-blinded controlled clinical trials validating the use of curcumin in epilepsy. The present article analyzes different preclinical evidence illustrating the effect of curcumin in seizure models. The review encourages carrying out clinical trials in this important area of research. In conclusion, curcumin might be beneficial in patients with epilepsy disorders, if its bioavailability issues are resolved.

Pharmaco-genetic therapeutics targeting parvalbumin neurons attenuate temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is the most common type of epilepsy and is often medically refractory. Previous studies suggest that selective pharmaco-genetic inhibition of pyramidal neurons has therapeutic value for the treatment of epilepsy, however there is a risk of disrupting normal physical functions. Here, we test whether pharmaco-genetic activation of parvalbumin neurons, which are transgenetically transduced with the modified muscarinic receptor hM3Dq can attenuate TLE. We found that pharmaco-genetic activation of hippocampal parvalbumin neurons in epileptogenic zone not only significantly extends the latency to different seizure stages and attenuates seizure activities in acute seizure model, but also greatly alleviates the severity of seizure onsets in two chronic epilepsy models. This manipulation did not affect the normal physical function evaluated in various cognitive tasks. Further, the activation of parvalbumin neurons produced an inhibition on parts of surrounding pyramidal neurons, and the direct inactivation of pyramidal neurons via the viral expression of a modified muscarinic receptor hM4Di produced a similar anti-ictogenic effect. Interestingly, pharmaco-genetic inactivation of pyramidal neurons was more sensitive to impair cognitive function. Those data demonstrated that pharmaco-genetic seizure attenuation through targeting parvalbumin neurons rather than pyramidal neurons may be a novel and relatively safe approach for treating refractory TLE.

The anti-epileptogenic and cognition enhancing effect of novel 1-[4-(4-benzo [1, 3] dioxol-5-ylmethyl-piperazin-1-yl)-phenyl]-3-phenyl-urea (BPPU) in pentylenetetrazole induced chronic rat model of epilepsy

Epilepsy is a chronic neurological disorder which affects 65 million worldwide population and characterized by recurrent seizure in epileptic patients. Recently, we reported a novel piperonylpiperazine derivative, BPPU “1-[4-(4-benzo [1,3]dioxol-5-ylmethyl-piperazin-1-yl)- phenyl]-3-phenyl-urea’’ as a potent anticonvulsant agent. BPPU has shown excellent anticonvulsant activity in various in-vivo seizure models along with good anti-depressant activity. In this report, we have deeply examined the anti-epileptogenic potential of BPPU in pentylenetetrazole (PTZ) induced kindling model and BPPU effectively reduced seizure episodes in kindled animals upto 35 days. Further, neuroprotective potential of BPPU against PTZ induced neurodegeneration has also been evaluated in hippocampus as well as cortex region by histopathological and immunohistochemical studies. Epileptic patients generally suffer from a range of cognitive impairments. Therefore, the cognition enhancing effect of BPPU was also measured by using well known social recognition test, novel object recognition test, light/dark test and open field test in kindled rat model as well as scopolamine induced memory deficit mice model. Results indicated that BPPU successfully improved cognition deficits in both models. Thus, BPPU appeared as a potent anti-epileptic agent which has also capability to improve cognition decline associated with epilepsy.

Commentary on "The impact of nonadherence to antiseizure drugs on seizure outcomes in an animal model of epilepsy".

The aim of this study was to understand the impact of human patterns of antiseizure drug (ASD) nonadherence on seizure control using a novel oral drug-delivery system in the kainate rat model of epilepsy. The main finding is that nonadherence to the ASD carbamazepine is associated with significant but reversible effects on seizure control, which shows that the model replicates clinical findings. As such, the study uses a reverse translational approach to validate the experimental paradigm chosen for these interesting series of experiments. As suggested by the authors, the experimental results demonstrate that animal studies of nonadherence can yield potentially important and translatable insights into the consequences of nonadherence on seizure control. An unexpected finding of the study was the lack of complete seizure control in most animals in the 100% perfect adherence group, indicating that the chronic epilepsy model used closely replicates mesial temporal lobe epilepsy with a high level of drug resistance. In addition to the experimental design of this first-of-a-kind pilot study, I was particularly impressed by the computer-controlled automated delivery system that provides tight control over chronic oral medication dosing in rats. In this respect, it is highly advantageous compared to conventional drug administration via the food or drinking water in rodents, which is associated with large circadian variation in drug intake.1 The innovative open-source drug-delivery system has been previously described in detail by Kyle Thomson and Steve White2 to allow its use by other investigators, which is to be saluted. I have no conflicts of interest to disclose. I confirm that I have read the Journal's position on issues involved in ethical publication and affirm that this report is consistent with those guidelines.

Sinomenine exerts anticonvulsant profile and neuroprotective activity in pentylenetetrazole kindled rats: involvement of inhibition of NLRP1 inflammasome

BackgroundEpilepsy is a common neurological disorder and is not well controlled by available antiepileptic drugs (AEDs). Inflammation is considered to be a critical factor in the pathophysiology of epilepsy. Sinomenine (SN), a bioactive alkaloid with anti-inflammatory effect, exerts neuroprotective activity in many nervous system diseases. However, little is known about the effect of SN on epilepsy.MethodsThe chronic epilepsy model was established by pentylenetetrazole (PTZ) kindling. Morris water maze (MWM) was used to test spatial learning and memory ability. H.E. staining and Hoechst 33258 staining were used to evaluate hippocampal neuronal damage. The expression of nucleotide oligomerization domain (NOD)-like receptor protein 1 (NLRP1) inflammasome complexes and the level of inflammatory cytokines were determined by western blot, quantitative real-time PCR and enzyme-linked immunosorbent assay (ELISA) kits.ResultsSN (20, 40, and 80 mg/kg) dose-dependently disrupts the kindling acquisition process, which decreases the seizure scores and the incidence of fully kindling. SN also increases the latency of seizure and decreases the duration of seizure in fully kindled rats. In addition, different doses of SN block the hippocampal neuronal damage and minimize the impairment of spatial learning and memory in PTZ kindled rats. Finally, PTZ kindling increases the expression of NLRP1 inflammasome complexes and the levels of inflammatory cytokines IL-1β, IL-18, IL-6, and TNF-α, which are all attenuated by SN in a dose- dependent manner.ConclusionsSN exerts anticonvulsant and neuroprotective activity in PTZ kindling model of epilepsy. Disrupting the kindling acquisition, which inhibits NLRP1 inflammasome-mediated inflammatory process, might be involved in its effects.

Corilagin Reduces the Frequency of Seizures and Improves Cognitive Function in a Rat Model of Chronic Epilepsy.

BackgroundWorldwide, epilepsy is an important chronic neurological condition. The aim of this study was to evaluate the effects of corilagin, an ellagitannin extracted from medicinal plants, on the frequency of seizures and cognitive function in a rat model of chronic epilepsy.Material/MethodsChronic epilepsy was induced in male Wistar rats by intraperitoneal (IP) injection of pentylenetetrazol (PTZ) for 36 days. Corilagin, 10 mg/kg and 20 mg/kg, was injected IP into treated rats, 24 days before the start of PTZ treatment, until the end of the protocol. The effects of corilagin were assessed by the pattern of epileptic seizures; cognitive function was assessed using the Morris water maze (MWM) navigation test. The mechanism of action of corilagin was investigated by measuring cytokine levels and oxidative stress parameters, including reactive oxygen species (ROS) production, and carbonic anhydrase inhibitory (CAI) activity. Histological analysis of fixed brain tissue sections included cresyl violet acetate staining (Nissl staining) for Nissl substance in the neuronal cytoplasm.ResultsThe corilagin-treated rats, compared with the control group, showed a significantly lower rate of epileptic events, improved cognitive function, reduced level of cytokines, reduced ROS production reduced CAI activity in the brain tissues (P<0.01). Histology of the rat brain tissues study showed that corilagin treatment maintained the neuronal cellular structure and number of surviving cells compared with the control group of rats.ConclusionsThe findings of this study showed that corilagin reduced the frequency of seizures and improved the cognitive function in a rat model of chronic epilepsy.

Seizure-induced reduction in glucose utilization promotes brain hypometabolism during epileptogenesis

Brain glucose hypometabolism is an early symptom of acquired epilepsy, its causative mechanism yet unclear. We suggest that a bidirectional positive feedback linking seizures and hypometabolism (hypometabolism induces seizures while seizures disrupt glucose metabolism) may be a primary cause for acquired epileptogenesis. We reported recently that chronic partial inhibition of brain glycolysis triggers epileptogenesis in healthy rats. Here, by monitoring dynamic electrical and multiple metabolic parameters before and following seizure generation in mouse hippocampal slices using the 4-aminopyridine model of epileptiform activity, we show that in turn seizures are followed by a long-lasting glucose hypometabolism, indicating possible existence of a positive feedback in the mechanism of epileptogenesis. Seizures were associated with acute oxidative stress that may contribute to the subsequent glucose metabolism impairment, since exogenous application of H2O2 replicated the post-seizure metabolic effects. Exogenous pyruvate, the principal mitochondrial energy substrate with a broad spectrum of neuroprotective properties, effectively normalized the post-seizure glucose consumption. We have shown recently that pyruvate exhibited a strong antiepileptic action in three rodent chronic epilepsy models, while in the present study we find that pyruvate effectively normalizes impaired glucose metabolism following seizures. Together, our results provide the mechanistic basis for the metabolic concept of acquired epileptogenesis and an efficient treatment strategy.

Different behavioral and pathological changes between epilepsy-associated depression and primary depression models

PurposeComorbid depression is common in patients with epilepsy. However, the epilepsy-associated depression is generally atypical and has not been fully recognized by neurologists. This study aimed to compare the behavioral and pathological changes between the chronic lithium chloride-pilocarpine rat epilepsy model (Licl-pilocarpine model) and the Chronic Unpredictable Mild Stress rat depression model (CUMS model), to evaluate for differences between epilepsy-associated depression and primary depression. MethodsThe Licl-pilocarpine model and the CUMS model were established respectively and simultaneously. Spontaneous seizures were recorded by video monitoring. Forced swim test (FST) and sucrose consumption test (SCT) were performed to test depressive behaviors. Immobility time (IMT) and climbing time (CMT) in FST, sucrose preference rate (SPR) in SCT, and weight gain rate (WGR) were adopted to represent severity of depressive behaviors in rats. Immunofluorescent staining was conducted to measure expressions of neuronal specific nuclear protein (NeuN), glial fibrillary acidic protein (GFAP), and cluster of differentiation molecule 11b (CD11b) in the hippocampus of Licl-pilocarpine model, CUMS model, and Control group. ResultsSignificantly, more prolonged IMT was observed in both the Licl-pilocarpine model (p<0.05) and the CUMS model (p<0.01) than Control group. But decreased WGR was only seen in the CUMS model. The percentage of rats with CMT greater than 100s was significantly higher in the Licl-pilocarpine model than the CUMS model (p<0.05). Increased CMT was observed in the Licl-pilocarpine model with mild depression subgroup (EMD, IMT≤100s) even compared with the Control group. Neuronal loss was both found in the Licl-pilocarpine model and the CUMS model when comparing with the Control group (p<0.05). However, the number of GFAP and CD11b staining cells was both greater in the Licl-pilocarpine model than the CUMS model and the Control group (p<0.05). ConclusionThere were some different depressive behavioral and hippocampal pathological changes between the Licl-pilocarpine and the CUMS models except for some common features. Gliosis and microglial activation might be more involved in the pathophysiology of epilepsy-associated depression than primary depression.

Effects of microRNA-129 and its target gene c-Fos on proliferation and apoptosis of hippocampal neurons in rats with epilepsy via the MAPK signaling pathway.

This study aims to investigate the effect of microRNA-129 (miR-129) on proliferation and apoptosis of hippocampal neurons in epilepsy rats by targeting c-Fos via the MAPK signaling pathway. Thirty rats were equally classified into a model group (successfully established as chronic epilepsy models) and a normal group. Expression of miR-129, c-Fos, bax, and MAPK was detected by RT-qPCR and Western blotting. Hippocampal neurons were assigned into normal, blank, negative control (NC), miR-129 mimic, miR-129 inhibitor, siRNA-c-Fos, miR-129 inhibitor+siRNA-c-Fos groups. The targeting relationship between miR-129 and c-Fos was predicted and verified by bioinformatics websites and dual-luciferase reporter gene assay. Cell proliferation after transfection was measured by MTT assay, and cell cycle and apoptosis by flow cytometry. c-Fos is a potential target gene of miR-129. Compared with the normal group, the other six groups showed a decreased miR-129 expression; increased expression of expression of c-Fos, Bax, and MAPK; decreased proliferation; accelerated apoptosis; more cells arrested in the G1 phase; and fewer cells arrested in the S phase. Compared with the blank and NC groups, the miR-129 mimic group and the siRNA-c-Fos group showed decreased expression of c-Fos, Bax, and MAPK, increased cells proliferation, and decreased cell apoptosis, fewer cells arrested in the G1 phase and more cells arrested in the S phase. However, the miR-129 inhibitor groups showed reverse consequences. This study suggests that miR-129 could inhibit the occurrence and development of epilepsy by repressing c-Fos expression through inhibiting the MAPK signaling pathway.

Discovery of novel Methylsulfonyl phenyl derivatives as potent human Cyclooxygenase-2 inhibitors with effective anticonvulsant action: Design, synthesis, in-silico, in-vitro and in-vivo evaluation

A novel series of methylsulfonyl phenyl derivatives has been designed and synthesized to evaluate their COX-2 inhibitory activity along with anti-convulsant potential. In-vitro evaluation revealed that two compounds MTL-1 and MTL-2 appeared as most potent and selective COX-2 inhibitors in the entire series. Anti-convulsant activity of both potent COX-2 inhibitors was assessed in sc-PTZ induced seizure test and MTL-1 excellently protected animals against PTZ induced seizure at the dose of 30 mg/kg. MTL-1 also indicates long duration of action in time course study and displayed significant seizure protection up to 6 h of drug administration. Further, the anti-epileptogenic effect of MTL-1 has been examined in PTZ induced chronic model of epilepsy. The results indicated that MTL-1 had a significant anti-epileptogenic effect in PTZ kindled rats as compared to Etoricoxib (ETX) and PTZ alone treated group. Additionally, MTL-1 successfully improved cognition deficit in PTZ kindled rats, which was confirmed by social recognition, novel object recognition and light-dark chamber tests. Moreover, molecular docking and molecular simulation (MD simulation) studies were also performed to elucidate the interaction of MTL-1 with the active site of COX-2 and results showed that MTL-1 suitably binds within active site of COX-2. To investigate the safety profile of MTL-1, a sub-acute toxicity study was also performed and MTL-1 emerged as a new non-toxic chemical entity. Thus, the present investigation discovered a potent and safe COX-2 inhibitor, which is endowed with an effective anti-epileptic action.

Safranal carried by nanostructured lipid vehicles inhibits generalized epilepsy in mice.

Safranal, a main component of Crocus sativus, is suggested to have neuroprotective effects. The aim of this study was to investigate the effect of safranal and nanostructured lipid vehicle (NLV) carried safranal in acute and chronic experimental mice models of epilepsy. In PILO acute seizure model, safranal dose-dependently extended latency to generalized seizure, decreased the highest seizure stages and the number of generalized seizures. Moreover, NLV carried safranal further enhanced the anti-seizure effect, which is comparable to the action of sodium valproate. Meanwhile, NLV carried safranal reduced and delayed the electroencephalogram spectra power after pilocarpine injection. In histological aspect, safranal dose-dependently reduced the loss of neurons induced by seizure and NLV system further improved this protection at the same dose. In MES acute model, safranal markedly increased the electroconvulsive threshold, where NLV further improved its effect. In PTZ chronic seizure model, NLV carried safranal significantly delayed the kindling rate of progress and the time it took to reach generalized seizures as compared to NLV control group. In conclusion, this study indicates that safranal inhibits generalized seizure in acute and chronic epilepsy models in mice and NLV can enhance this effect. So, NLV carried safranal may have potential value in treatment of generalized epilepsy.