Anti-inflammatory treatment with a soluble epoxide hydrolase inhibitor attenuates seizures and epilepsy-associated depression in the LiCl-pilocarpine post-status epilepticus rat model

CRMP2 regulates mossy fiber sprouting and modulates microtubule dynamics in a pilocarpine induced rat model of epilepsy

OBJECTIVE

Our study aimed to investigate the role of CRMP2 in mossy fiber sprouting (MFS) using a pilocarpine-induced rat model of epilepsy.

METHODS

First, the rats were sacrificed on the 1, 7, 14 and 28 day after pilocarpine injection. Quantitative Real-time PCR (qPCR) and Western blot (WB) were performed to assess mRNA and protein levels in the hippocampus and cortex. Next, shCRMP2 AAV was injected into the dentate gyrus of hippocampus to knock down CRMP2 expression. Two weeks later, the epileptic rat model was induced by pilocarpine injection. On the day of status epilepticus (SE) induction, animals in the shCtrl + EP + LCM and shCRMP2 + EP + LCM group received twice-daily intragastric administration of Lacosamide (LCM). The rats were video monitored from day 7 to 28, and were sacrificed on day 28 after pilocarpine injection for subsequent experiment.

RESULTS

In the present study, we observed downregulation of phosphorylated CRMP2 in the hippocampus of epileptic rats. Additionally, LCM treatment reduces the expression level of CRMP2 protein in the hippocampus of these rats. Both CRMP2 knockdown and LCM treatment were found to decrease mossy fiber sprouting (MFS) in the dentate gyrus and shorten the duration of seizures in epileptic rats. Furthermore, we discovered that microtubule dynamics are reduced in the hippocampus of epileptic rats. Both CRMP2 Knockdown and LCM treatment were shown to increase the microtubule dynamics in the hippocampus of rats with epilepsy.

CONCLUSION

In conclusion, we demonstrated convincingly that CRMP2 regulates mossy fiber sprouting and modulates microtubule dynamics in a pilocarpine induced rat model of epilepsy.

Expression pattern of Arc in the hippocampus of a rat model of epilepsy and depression comorbidity

BACKGROUND

Two key factors associated with the comorbidity of epilepsy and depression (EAD), activity regulated cytoskeletal protein (Arc) and homer protein homolog 1 (Homer1), were previously identified by our group through bioinformatics methods (Yu et al., 2022). The expression of Arc and Homer1 were verified through animal experiments.

METHODS

Six-week-old male specific pathogen-free grade Sprague Dawley rats (weighing 200 ± 20 g) received intraperitoneal injection of lithium chloride (LiCl)-pilocarpine for status epilepticus (SE) induction. SE was terminated after 30 min by intraperitoneal injection of diazepam, and spontaneous SE in rats was monitored by video for 2 weeks. The control group (Con group) was injected with an equal dose of sterile normal saline. Subsequently, EAD rats (EAD group) were selected from rat models of LiCl-pilocarpine-induced chronic epilepsy according to the immobility time of the forced swimming test on day 14 after LiCl-pilocarpine induced epilepsy. The remaining rats were included in the epilepsy group (EP group). Depression-like behaviors were evaluated using sucrose preference, open-field, and forced swimming tests. Body weight, sucrose preference percentage, the total distance of the open-field test, the average speed, the number of upright times, and the immobility time of the forced swimming test were assessed 14 and 28 days after LiCl-pilocarpine induced epilepsy. Rats in the EAD and EP groups were monitored by video for 2 weeks, and the frequency, grade, and duration of chronic spontaneous epileptic seizures were recorded. Epileptic seizures were compared between the EAD and EP groups. The expression of activity-regulated cytoskeletal protein (Arc) and Homer protein homolog 1 (Homer1) in the hippocampus of each group was detected by real-time quantitative PCR and western blot analysis. The fluorescence intensity of Arc in the hippocampus of each group was detected by immunofluorescence (IF) assay.

RESULTS

Compared with the Con and EP groups, rats in the EAD group exhibited a decreased body weight on day 28, a significant decrease in sucrose preference percentage on days 14 and 28, significantly extended immobility time, and significantly reduced total travel, average speed, the number of upright times. No significant differences in the number, grade, and duration of seizures were observed between the EAD and EP groups. Meanwhile, the expression level of Arc in the hippocampus was significantly decreased in the EAD group compared with the Con and EP groups; however, the expression level of Homer1 showed no significant change. IF results showed that Arc was mainly expressed in the cytoplasm, and the fluorescence intensity of Arc in hippocampal CA1, DG, and CA3 was lower in the EAD group than in the Con and EP groups.

CONCLUSIONS

The expression of Arc in the hippocampal tissue of EAD rats is significantly decreased, suggesting that Arc is associated with EAD.

Suppression of PINK1 autophosphorylation attenuates pilocarpine-induced seizures and neuronal injury in rats

PTEN-induced kinase 1 (PINK1) autophosphorylation triggers the PINK1/Parkin pathway, which is the main mitophagic pathway in the mammalian nervous system. In the present study, we aimed to mechanistically explore the role of PINK1 in pilocarpine-induced status epilepticus (SE) in Sprague-Dawley rats. Evidence from immunohistochemistry, western blotting, biochemical assays, and behavioral testing showed that pilocarpine-induced SE led to increased levels of PINK1 phosphorylation, mitophagy, mitochondrial oxidative stress, neuronal damage and learning and memory deficits. Using shRNA interference to suppress the expression of translocase outer mitochondrial membrane 7, a positive regulator of PINK1 autophosphorylation, lowered the increased levels of phosphorylated PINK1 following pilocarpine administration. It also reduced the levels of mitophagy, mitochondrial oxidative stress and neuronal damage, and attenuated seizure severity and cognitive deficits. In contrast, suppressing the expression of overlapping with the m-AAA protease 1 homolog, a negative regulator of PINK1 autophosphorylation, led to higher levels of phosphorylated PINK1 following pilocarpine administration. It also led to more serious mitophagy, neuronal damage, as well as worsened seizure severity and cognitive deficits. Our results indicate that PINK1 autophosphorylation plays a vital role in epileptic seizures and neuronal injury by mediating mitophagy. Regulating PINK1 autophosphorylation may change the adverse consequences of epilepsy, and may be an effective neuroprotective strategy.

Inhibiting the soluble epoxide hydrolase increases the EpFAs and ERK1/2 expression in the hippocampus of LiCl-pilocarpine post-status epilepticus rat model

Purpose

This study aimed to investigate the enzyme activity of soluble epoxide hydrolase (sEH) and quantify its metabolic substrates, namely epoxygenated fatty acids (EpFAs), and products of sEH in the hippocampus after administering TPPU [1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl)urea], an inhibitor of sEH. Furthermore, it explored whether the extracellular signal-activated protein kinase 1/2 (ERK1/2) is involved in the anti-seizure effects of TPPU in the lithium chloride (LiCl)-pilocarpine induced post-status epilepticus (SE) rat model.

Methods

The rats were intraperitoneally (I.P.) injected with LiCl and pilocarpine to induce SE and then spontaneous recurrent seizures (SRS) were observed. Rats were randomly assigned into SRS + TPPU group (intragastrically administering 0.1 mg/kg/d TPPU), SRS + Vehicle group (administering the vehicle instead), and Control group. Enzyme-linked immunosorbent assay, Western-blot analysis, and ultra-high-performance liquid chromatography/mass spectrometry (LC/MS) were performed to measure the enzyme activity of sEH, the protein level of sEH and ERK1/2, and the concentration of TPPU and polyunsaturated fatty acids (PUFAs) metabolisms in the hippocampus.

Results

The frequency of SRS events of Racine stage 3 or higher ranged from 0 to 19 per week in the SRS + Vehicle group, compared to 0-5 per week in the SRS + TPPU group. sEH enzyme activity and protein levels were significantly elevated in the SRS + Vehicle group compared to the Control group. After TPPU administration, the hippocampal TPPU concentration reached 10.94 ± 4.37 nmol/kg. sEH enzyme activity was significantly reduced in the LiCl-pilocarpine-induced post-SE rat model, although sEH protein levels did not decrease significantly. The regioisomers 8,9-, 11,12-, and 14,15-EETs, total EETs, the EETs/DHETs ratio, other EpFAs including 16(17)-EpDPA, and the 19(20)-EpDPA/19,20-DiHDPA ratio in the hippocampus were significantly increased. Additionally, the p-ERK1/2 to ERK1/2 ratio in the hippocampus was significantly elevated following TPPU administration.

Conclusion

This study demonstrates that inhibiting sEH with TPPU increases the levels of EETs, other EpFAs, and ERK1/2 expression in the hippocampus of a LiCl-pilocarpine-induced post-SE rat model. These findings suggest that the anti-seizure effect of TPPU may be mediated through the EETs-ERK1/2 pathway.

Inhibiting Soluble Epoxide Hydrolase Suppresses NF-κB p65 Signaling and Reduces CXCL10 Expression as a Potential Therapeutic Target in Hashimoto's Thyroiditis

BACKGROUND

Although Hashimoto's thyroiditis (HT) is one of most common autoimmune thyroid diseases, its treatment remains focused on symptom relief. The soluble epoxide hydrolase (sEH) shows potential functions as a drug target in alleviating some autoimmune diseases; however, we seldom know its role in HT.

METHODS

The protein expression of sEH and related downstream molecules were evaluated by immunohistochemistry, Western blotting, ELISA, or immunofluorescence staining. RNA sequencing of tissue samples was performed to analyze differential genes and dysregulated pathways in HT and controls. The thyroid follicular epithelial cells (TFECs) and rat HT model were used to verify the biological function of sEH and the inhibition role of adamantyl-ureido-dodecanoic acid (AUDA) in HT.

RESULTS

The sEH was significantly upregulated in HT patients compared with healthy individuals. Transcriptome sequencing showed cytokine-related pathways and chemokine expression; especially chemokine CXCL10 and its receptor CXCR3 were aberrant in HT patients. In TFECs and a rat HT model, blocking sEH by AUDA inhibitor could effectively inhibit the autoantibody, proinflammatory nuclear kappa factor B (NF-κB) signaling, chemokine CXCL10/CXCR3 expression, and type-1 helper CD4+ T cells.

CONCLUSION

Our findings suggest that sEH/NF-κB p65/CXCL10-CXCR3 might be promising therapeutic targets for HT.

Cannabinoid receptor 2 agonist AM1241 alleviates epileptic seizures and epilepsy-associated depression via inhibiting neuroinflammation in a pilocarpine-induced chronic epilepsy mouse model

Increasing evidence suggests that cannabinoid receptor 2 (CB2R) serves as a promising anti-inflammatory target. While inflammation is known to play crucial roles in the pathogenesis of epilepsy, the involvement of CB2R in epilepsy remains unclear. This study aimed to investigate the effects of a CB2R agonist, AM1241, on epileptic seizures and depressive-like behaviors in a mouse model of chronic epilepsy induced by pilocarpine. A chronic epilepsy mouse model was established by intraperitoneal administration of pilocarpine. The endogenous cannabinoid system (eCBs) in the hippocampus was examined after status epilepticus (SE). Animals were then treated with AM1241 and compared with a vehicle-treated control group. Additionally, the role of the AMPK/NLRP3 signaling pathway was explored using the selective AMPK inhibitor dorsomorphin. Following SE, CB2R expression increased significantly in hippocampal microglia. Administration of AM1241 significantly reduced seizure frequency, immobility time in the tail suspension test, and neuronal loss in the hippocampus. In addition, AM1241 treatment attenuated microglial activation, inhibited pro-inflammatory polarization of microglia, and suppressed NLRP3 inflammasome activation in the hippocampus after SE. Further, the therapeutic effects of AM1241 were abolished by the AMPK inhibitor dorsomorphin. Our findings suggest that CB2R agonist AM1241 may alleviate epileptic seizures and its associated depression by inhibiting neuroinflammation through the AMPK/NLRP3 signaling pathway. These results provide insight into a novel therapeutic approach for epilepsy.

Fisetin-loaded chitosan nanoparticles ameliorate pilocarpine-induced temporal lobe epilepsy and associated neurobehavioral alterations in mice: Role of ROS/TNF-α-NLRP3 inflammasomes pathway

Fisetin has displayed potential as an anticonvulsant in preclinical studies yet lacks clinical validation. Challenges like low solubility and rapid metabolism may limit its efficacy. This study explores fisetin-loaded chitosan nanoparticles (NP) to address these issues. Using a murine model of pilocarpine-induced temporal lobe epilepsy, we evaluated the anticonvulsant and neuroprotective effects of fisetin NP. Pilocarpine-induced seizures and associated neurobehavioral deficits were assessed after administering subtherapeutic doses of free fisetin and fisetin NP. Changes in ROS, inflammatory cytokines, and NLRP3/IL-18 expression in different brain regions were estimated. The results demonstrate that the fisetin NP exerts protection against seizures and associated depression-like behavior and memory impairment. Furthermore, biochemical, and histological examinations supported behavioral findings suggesting attenuation of ROS/TNF-α-NLRP3 inflammasome pathway as a neuroprotective mechanism of fisetin NP. These findings highlight the improved pharmacodynamics of fisetin using fisetin NP against epilepsy, suggesting a promising therapeutic approach against epilepsy and associated behavioral deficits.

Frontiers and hotspots in comorbid epilepsy and depression: a bibliometric analysis from 2003 to 2023

Background

Epilepsy ranks among the most common neurological disorders worldwide, frequently accompanied by depression as a prominent comorbidity. This study employs bibliometric analysis to reveal the research of comorbid epilepsy and depression over the past two decades, aiming to explore trends and contribute insights to ongoing investigations.

Methods

We conducted a comprehensive search on the Web of Science Core Collection database and downloaded relevant publications on comorbid epilepsy and depression published from 2003 to 2023. VOSviewer and CiteSpace were mainly used to analyze the authors, institutions, countries, publishing journals, reference co-citation patterns, keyword co-occurrence, keyword clustering, and other aspects to construct a knowledge atlas.

Results

A total of 5,586 publications related to comorbid epilepsy and depression were retrieved, with a general upward trend despite slight fluctuations in annual publications. Publications originated from 121 countries and 636 institutions, with a predominant focus on clinical research. The United States led in productivity (1,529 articles), while Melbourne University emerged as the most productive institution (135 articles). EPILEPSY & BEHAVIOR was the journal with the highest publication output (1,189 articles) and citation count. Keyword analysis highlighted emerging trends, including "recognitive impairment" and "mental health," indicating potential future research hotspots and trends.

Conclusion

This study is one of the first to perform a bibliometric analysis of the 20-year scientific output of comorbid epilepsy and depression. While research has trended upwards, ambiguity in pathogenesis and the absence of standardized diagnostic guidelines remain concerning. Our analysis offers valuable guidance for researchers, informing that this might be a strong area for future collaborations.

Effect of Shenqi Jieyu formula on inflammatory response pathway in hippocampus of postpartum depression rats

Aim

To investigate whether SJF functions in similar manner as the key substance in the inflammatory process, soluble epoxide hydrolase (sEH) inhibitor, to inhibit the arachidonic acid metabolic pathway and nuclear factor kappa-B(NF-κB) signal path in the hippocampi of postpartum depression rats.

Methods

The rats were subcutaneous injected estradiol benzoate and progesterone to build PPD rat model. SJF, paroxetine hydrochloride and sEH inhibitor (AUDA) were used to treat PPD rats for 3 weeks. Then the morphological changes of hippocampi and various proteins were observed after that behavioral test were conducted in all 36 SD rats in six group: SJF, paroxetine, AUDA, PPD, sham and normal group.

Results

Weight, results of sucrose preference, upright times, total and center squares crossing decreased significantly (P < 0.01), whereas immobility time increased (P < 0.01). Results above were reversed in animals that in the SJF, paroxetine and AUDA groups. Hippocampal neurons in PPD rats partially degenerated with narrowed nuclei, increased autophagy and mitochondria bound to lysosomes were visible while the autophagy of hippocampal neurons in the paroxetine and AUDA group decreased, with a small amount of lysosomes. sEH, COX-2, 5-LOX, TNF-α, IL-1, IL-6, NF-κB p65, and Cor increased in hippocampi of PPD rats while EETs and 5-HT decreased. Protein expressions of Ibal, GFAP, p-IκBα, p65, and p-p65(S536)increased in PPD animals. Those changes were reversed by SJF, paroxetine and AUDA. Gene expressions of TNF-α, IL-1β, IL-6, 5-LOX, COX-2 and p65 increased in PPD rats and the changes of expression in these genes were reversed by paroxetine and AUDA. SJF reversed the gene expression changes of COX-2, TNF-α, and IL-1β.

Conclusion

SJF may have an analogous effect as sEH inhibitor to relieve depressive symptoms by suppressing inflammatory signaling pathways in hippocampi of PPD rats, which involves AA metabolic pathway and NF-κB signal pathway.

Pharmacological inhibition of S6K1 rescues synaptic deficits and attenuates seizures and depression in chronic epileptic rats

BACKGROUND

Recent studies have shown that mTOR signaling plays an important role in synaptic plasticity. However, the function of S6K1, the mechanistic target of rapamycin kinase complex 1 (mTORC1) substrate, in epilepsy remains unknown.

AIMS

Our present study aimed to explore the mechanism by which S6K1 is involved in chronic epilepsy.

METHODS

First, immunostaining was used to measure neurite length and complexity in kainic acid (KA)-treated primary cultured neurons treated with PF-4708671, a highly selective S6K1 inhibitor. We obtained evidence for the role of S6K1 in protecting and promoting neuronal growth and development in vitro. Next, to explore the function and mechanism of the S6K1 inhibitor in epilepsy, a pilocarpine-induced chronic epileptic rat model was established. In vivo electrophysiology (including local field potentiation in CA1 and long-term potentiation), depression/anxiety-like behavior tests, and Golgi staining were performed to assess seizure behavior, power spectral density, depression/anxiety-like behavior, and synaptic plasticity. Furthermore, western blotting was applied to explore the potential molecular mechanisms.

RESULTS

We found that inhibition of S6K1 expression significantly decreased seizures and depression-like behavior and restored power at low frequencies (1-80 Hz), especially in the delta, theta, and alpha bands, in chronic epileptic rats. In addition, PF-4708671 reversed the LTP defect in hippocampal CA3-CA1 and corrected spine loss and dendritic pathology.

CONCLUSION

In conclusion, our data suggest that inhibition of S6K1 attenuates seizures and depression in chronic epileptic rats via the rescue of synaptic structural and functional deficits. Given the wide range of physiological functions of mTOR, inhibition of its effective but relatively simple functional downstream molecules is a promising target for the development of drugs for epilepsy.

Soluble epoxide hydrolase inhibitor (TPPU) alleviates ferroptosis by regulating CCL5 after intracerebral hemorrhage in mice

Soluble epoxide hydrolase (sEH) inhibition has been shown multiple beneficial effects against brain injuries of Intracerebral hemorrhage (ICH). However, the underlying mechanism of its neuroprotective effects after ICH has not been explained fully. Ferroptosis, a new form of iron-dependent programmed cell death, has been shown to be implicated in the secondary injuries after ICH. In this study, We examined whether sEH inhibition can alleviate brain injuries of ICH through inhibiting ferroptosis. Expression of several markers for ferroptosis was observed in the peri-hematomal brain tissues in mice after ICH. lip-1, a ferroptosis inhibitor, alleviated iron accumulation, lipid peroxidation and the secondary damages post-ICH in mice model. Intraperitoneal injection of 1-Trifluoromethoxyphenyl-3- (1-propionylpiperidin-4-yl)urea (TPPU), a highly selective sEH inhibitor, could inhibit ferroptosis and alleviate brain damages in ICH mice. Furthermore, RNA-sequencing was applied to explore the potential regulatory mechanism underlying the effects of TPPU in ferroptosis after ICH. C-C chemokine ligand 5 (CCL5) may be the key factor by which TPPU regulated ferroptosis after ICH since CCL5 antagonist could mimic the effects of TPPU and CCL5 reversed the inhibitive effect of TPPU on ferroptosis and the neuroprotective effects of TPPU on secondary damage after ICH. Taken together, these data indicate that ferroptosis is a key pathological feature of ICH and Soluble epoxide hydrolase inhibitor can exert neuroprotective effect by preventing ferroptosis after ICH.

Epilepsy is more than a simple seizure disorder: Causal relationships between epilepsy and its comorbidities

This review draws connections between the pathogenesis of canine epilepsy and its most commonly recognised comorbidities: cognitive impairment (CI), attention deficit hyperactivity disorder (ADHD)-like behaviour, fear and anxiety. Uni/bidirectional causalities and the possibility of a common aetiology triggering both epilepsy and the associated diseases are considered. Research on this topic is sparse in dogs, so information has been gathered and assessed from human and laboratory animal studies. Anatomical structures, functional connections, disrupted neurotransmission and neuroinflammatory processes collectively serve as a common foundation for epilepsy and its comorbidities. Specific anatomical structures, especially parts of the limbic system, such as the amygdala and the hippocampus, are involved in generating seizures, as well as cognitive- and behavioural disorders. Furthermore, disturbances in inhibitory and excitatory neurotransmission influence neuronal excitability and networks, leading to underlying brain dysfunction. Functional magnetic resonance imaging (fMRI), interictal epileptiform discharges (IEDs), and electroencephalography (EEG) have demonstrated functional brain connections that are related to the emergence of both epilepsy and its various comorbidities. Neuroinflammatory processes can either cause or be a consequence of seizures, and inflammatory mediators, oxidative stress and mitochondrial dysfunction, can equally evoke mood disorders. The extensive relationships contributing to the development and progression of seizures and comorbid cognitive and behavioural conditions illustrate the complexity of the disease that is epilepsy.

Soluble epoxide hydrolase inhibitor blockage microglial cell activation in subnucleus caudalis in a persistent model of arthritis

Rheumatoid arthritis (RA) is a chronic condition characterized by pain and infiltration of immune cells into the joint. Immune cells can be activated, producing inflammatory cytokines, leading to continuously degenerative and inflammatory reactions and the temporomandibular joint (TMJ) can be affected by RA. In this scenario, novel targets are needed to increase treatment efficacy with minimized side effects. The epoxy-eicosatrienoic acids (EETs), are endogenous signaling molecules, playing important roles in diminishing inflammation and pain but are promptly metabolized by soluble epoxide hydrolase (sEH), generating less-bioactive acids.Therefore, sEH inhibitors is an interest therapeutic target to enhance the beneficial effect of natural EETs. TPPU is a potent sEH inhibitor that is capable of dampening EETs hydrolysis. Thus, we aimed to assess the impact of pharmacological sEH inhibition on a persistent model of albumin-induced arthritis in the TMJ, in two scenarios: first, as post-treatment, in an installed arthritic condition, and second, the protective role, in preventing the development of an arthritic condition. In addition, we investigate the influence of sEH inhibition on microglia cell activation in the trigeminal subnucleus caudalis (TSC) and in vitro experiments. Finally, we examined the astrocyte phenotype. Oral administration of TPPU, acts in multiple pathways, in a protective and reparative post-treatment, ameliorating the preservation of the TMJ morphology, reducing the hypernociception, with an immunosuppressive action reducing neutrophil and lymphocytes and pro-inflammatory cytokines in the TMJ of rats. In TSC, TPPU reduces the cytokine storm and attenuates the microglia activated P2X7/Cathepsin S/Fractalkine pathway and reduces the astrocyte activation and glutamate levels. Collectively, our findings revealed that sEH inhibition mitigates hypersensitive nociception through the regulation of microglia activation and astrocyte modulation, demonstrating the potential use of sEH inhibitors as immunoresolvents in the treatment of autoimmune disorders.

Propofol mitigates brain injury and oxidative stress, and enhances GABAA receptor α1 subunit expression in a rat model of lithium chloride-pilocarpine induced status epilepticus

Background/aim

Propofol is a positive allosteric modulator of GABAA receptor (GABAAR) and has potent antioxidant activity. The aim of this study was to investigate the effect of propofol on damage to the cerebral cortex and hippocampus in a lithium chloride (LiCl)-pilocarpine animal model of status epilepticus (SE).

Materials and methods

Adult male Sprague Dawley rats were injected with LiCl-pilocarpine to induce SE. They were then randomized and injected 30 min later with vehicle saline (SE+saline), propofol (SE+PPF, 50 mg/kg), Diazepam (SE+DZP, 10 mg/kg), Scopolamine (SE+SCOP, 10 mg/kg), or MK-801 (SE+MK-801, 2 mg/kg). Another group of rats received saline only and served as the naïve control (BLK). The levels of superoxide dismutase (SOD), glutathione (GSH) and malondialdehyde (MDA) in the serum, cortex and hippocampus were analyzed 2 and 24 h posttreatment. The degree of tissue damage in the cortex and hippocampus of individual rats was assessed 24 h posttreatment, together with expression of the GABAAR α1 subunit.

Results

The propofol group showed reduced levels of tissue damage in the cerebral cortex and hippocampus, decreased levels of MDA, and increased levels of GSH compared to the SE+saline group. No changes in SOD level were observed in serum and tissue samples from the cortex and hippocampus of SE+saline rats. Immunohistochemistry and Western blot assays showed that propofol treatment significantly increased the expression of GABAAR α1 subunit in the cortical and hippocampal tissues of SE rats.

Conclusion

Propofol treatment protected against SE-induced tissue injury in the cortex and hippocampus of rats. This was due at least in part to its antioxidant activity and to its induction of GABAAR α1 subunit expression in the brain.

Reduction of seizures and inflammatory markers by betamethasone in a kindling seizure model

Epilepsy is a chronic disease characterized by an ongoing predisposition to seizures. Although inflammation has emerged as a crucial factor in the etiology of epilepsy, no approaches to anti-inflammatory treatment have been clinically proven to date. Betamethasone (a corticosteroid drug used in the clinic for its anti-inflammatory and immunosuppressive effects) has never been evaluated in attenuating the intensity of seizures in a kindling animal model of seizures. Using a kindling model in male wistar rats, this study evaluated the effect of betamethasone on the severity of seizures and levels of pro-inflammatory interleukins. Seizures were induced by pentylenetetrazole (30 mg/kg) on alternate days for 15 days. The animals were divided into four groups: a control group treated with saline, another control group treated with diazepam (2 mg/kg), and two groups treated with betamethasone (0.125 and 0.250 mg/kg, respectively). Open field test was conducted. Betamethasone treatments were effective in reducing the intensity of epileptic seizures. There were lower levels of Tumor Necrosis Factor-α and interleukin-1β in the cortex, compared to the saline group, on the other hand, levels in the hippocampus remained similar to the control groups. There was no change in the levels of interleukin-6 in the evaluated structures. Serum inflammatory mediators remained similar. Lower quantities of inflammatory mediators in the central nervous system may have been the key to the reduced severity of seizures on the Racine scale.

The increase of Nrf2 m6A modification induced by FTO downregulation promotes hippocampal neuron injury and aggravates the progression of epilepsy in a rat model

Epilepsy is a common chronic neurological disorder characterized by widespread neuronal death. The purpose of this study was to investigate the role of nuclear factor erythroid 2-related factor 2 (Nrf2) m6A methylation in epilepsy. To create epileptic models, the rats were given Lithium chloride and pilocarpine, and isolated primary rat hippocampal neurons were cultured in an Mg2⁺ -free medium. The frequency of seizures was recorded in the epilepsy group of rats. The functional tests included TUNEL, MTT, and flow cytometry. Mechanistically, RNA degradation assay, RNA immunoprecipitation, and methylated RNA immunoprecipitation were performed. In epileptic models, Nrf2 and fat mass and obesity-associated (FTO) levels were downregulated, whereas YT521-B homology (YTH) domain family protein 2 (YTHDF2) was upregulated. Additionally, in epileptic models, there was a rise in the m6A methylation level of Nrf2 mRNA. Overexpressing FTO increased cell viability and reduced apoptosis, but Nrf2 interference reversed these effects. Meanwhile, FTO overexpression decreased the m6A methylation of Nrf2 mRNA. Moreover, YTHDF2 bound to Nrf2 mRNA and decreased its stability. Furthermore, FTO overexpression reduced seizure frequency in rats and inhibited hippocampal neuron apoptosis via lowering the m6A methylation level of Nrf2 mRNA. Overexpressing FTO reduced m6A methylation of Nrf2 mRNA, increased cell viability, suppressed apoptosis, and slowed the progression of epileptic diseases, which is linked to YTHDF2 binding to m6A-modified Nrf2 and promoting its degradation, as well as downregulating Nrf2 expression in hippocampal neurons.

Inflammatory properties of diet mediate the effect of epilepsy on moderate to severe depression: Results from NHANES 2013-2018

BACKGROUND

Depression is a major public health problem, and epilepsy and a high-inflammatory diet are important causes of depression. We aimed to explore the level of dietary inflammation in epileptic patients and its relationship with moderate to severe depression (MSD).

METHODS

This cross-sectional study included 12,788 participants aged 20-80 years from the NHANES database from 2013 to 2018. Depressive symptoms were evaluated using the nine-item Patient Health Questionnaire (PHQ-9), and epilepsy was diagnosed based on the use of antiepileptic drugs within the previous 30 days. Dietary inflammatory index (DII) scores and energy-adjusted DII (E-DII) scores were calculated based on dietary recalls of the past 24 h, and average DII (ADII) and energy-adjusted ADII (E-ADII) were calculated based on two 24-hour dietary recalls.

RESULTS

The DII, E-DII, and ADII scores and prevalence of MSD were significantly increased in epileptic patients compared with non-epilepsy subjects. The E-ADII score (P = 0.078) was weakly associated with comorbid MSD in patients with epilepsy. Mediation models showed that dietary inflammation scores mediated 2.31 % to 12.25 % of epilepsy-related MSD. In stratified analysis, an increased prevalence of MSD was present in the Quartile 2 subgroup based on DII and E-ADII scores and in the Quartile 3 subgroup of epileptic patients based on DII, E-DII, and ADII scores.

CONCLUSIONS

Epileptics consume more proinflammatory foods and nutrients than control subjects. MSD in patients with epilepsy is associated with their high inflammatory diet. Suggesting an urgent need for rational dietary management in the epileptic population.

LncRNA PVT1 Promotes Neuronal Cell Apoptosis and Neuroinflammation by Regulating miR-488-3p/FOXD3/SCN2A Axis in Epilepsy

It is vital to understand the mechanism of epilepsy onset and development. Dysregulated lncRNAs are closely associated with epilepsy. Our work probed the role of lncRNA PVT1/miR-488-3p/FOXD3/SCN2A axis in epilepsy. The mRNA and protein expressions were assessed using qRT-PCR and western blot. MTT assay and TUNEL staining were conducted to assess cell viability and apoptosis, respectively. TNFα, IL-1β and IL-6 levels were analyzed using ELISA. LDH level was tested by Assay Kit. The binding relationship between PVT1, miR-488-3p and FOXD3 were verified using dual luciferase reporter gene assay. The epilepsy model of rats was established by lithium-pilocarpine injection. Nissl staining was performed to evaluate neuronal damage. PVT1 was markedly upregulated in epilepsy model cells. Knockdown of PVT1 increased the viability, while repressed the apoptosis and inflammatory cytokines secretion as well as LDH level in epilepsy cell model. MiR-488-3p alleviated neuronal injury and neuroinflammation in model cells. MiR-488-3p functioned as the direct target of PVT1, and its inhibition neutralized the effects of PVT1 silencing on neuronal cell injury and neuroinflammation in model cells. Furthermore, miR-488-3p inhibited neuronal cell injury and neuroinflammation in model cells by regulating FOXD3/SCN2A pathway. Finally, animal experiments proved that PVT1 promoted epilepsy-induced neuronal cell injury and neuroinflammation by regulating miR-488-3p-mediated FOXD3/SCN2A pathway. PVT1 promoted neuronal cell injury and inflammatory response in epilepsy via inhibiting miR-488-3p and further regulating FOXD3/SCN2A pathway.

Sex-Specific Response of the Brain Free Oxylipin Profile to Soluble Epoxide Hydrolase Inhibition

Oxylipins are the oxidation products of polyunsaturated fatty acids and have been implicated in neurodegenerative disorders, including dementia. Soluble epoxide hydrolase (sEH) converts epoxy-fatty acids to their corresponding diols, is found in the brain, and its inhibition is a treatment target for dementia. In this study, male and female C57Bl/6J mice were treated with an sEH inhibitor (sEHI), trans-4-[4-(3-adamantan-1-yl-ureido)-cyclohexyloxy]-benzoic acid (t-AUCB), for 12 weeks to comprehensively study the effect of sEH inhibition on the brain oxylipin profile, and modulation by sex. Ultra-high-performance liquid chromatography-tandem mass spectrometry was used to measure the profile of 53 free oxylipins in the brain. More oxylipins were modified by the inhibitor in males than in females (19 versus 3, respectively) and favored a more neuroprotective profile. Most were downstream of lipoxygenase and cytochrome p450 in males, and cyclooxygenase and lipoxygenase in females. The inhibitor-associated oxylipin changes were unrelated to serum insulin, glucose, cholesterol, or female estrous cycle. The inhibitor affected behavior and cognitive function as measured by open field and Y-maze tests in males, but not females. These findings are novel and important to our understanding of sexual dimorphism in the brain's response to sEHI and may help inform sex-specific treatment targets.

Scoping review of disease-modifying effect of drugs in experimental epilepsy

Objective

Epilepsy affects ~50 million people worldwide causing significant medical, financial, and sociologic concerns for affected patients and their families. To date, treatment of epilepsy is primarily symptomatic management because few effective preventative or disease-modifying interventions exist. However, recent research has identified neurobiological mechanisms of epileptogenesis, providing new pharmacologic targets to investigate. The current scientific evidence remains scattered across multiple studies using different model and experimental designs. The review compiles different models of anti-epileptogenic investigation and highlights specific compounds with potential epileptogenesis-modifying experimental drugs. It provides a platform for standardization of future epilepsy research to allow a more robust compound analysis of compounds with potential for epilepsy prevention.

Methods

PubMed, Ovid MEDLINE, and Web of Science were searched from 2007 to 2021. Studies with murine models of epileptogenesis and explicitly detailed experimental procedures were included in the scoping review. In total, 51 articles were selected from 14,983 and then grouped by five core variables: (1) seizure frequency, (2) seizure severity, (3) spontaneous recurrent seizures (SRS), (4) seizure duration, and (5) mossy fiber sprouting (MFS). The variables were differentiated based on experimental models including methods of seizure induction, treatment schedule and timeline of data collection. Data was categorized by the five core variables and analyzed by converting original treatment values to units of percent of its respective control.

Results

Discrepancies in current epileptogenesis models significantly complicate inter-study comparison of potential anti-epileptogenic interventions. With our analysis, many compounds showed a potential to reduce epileptogenic characteristics defined by the five core variables. WIN55,212-2, aspirin, rapamycin, 1400W, and LEV + BQ788 were identified compounds with the potential of effective anti-epileptic properties.

Significance

Our review highlights the need for consistent methodology in epilepsy research and provides a novel approach for future research. Inconsistent experimental designs hinder study comparison, slowing the progression of treatments for epilepsy. If the research community can optimize and standardize parameters such as methods of seizure induction, administration schedule, sampling time, and aniMal models, more robust meta-analysis and collaborative research would follow. Additionally, some compounds such as rapamycin, WIN 55,212-2, aspirin, 1400W, and LEV + BQ788 showed anti-epileptogenic modulation across multiple variables. We believe they warrant further study both individually and synergistically.

Neuroprotection of cannabidiol in epileptic rats: Gut microbiome and metabolome sequencing

AIMS

Epilepsy is a neurological disease occurring worldwide. Alterations in the gut microbial composition may be involved in the development of Epilepsy. The study aimed to investigate the effects of cannabidiol (CBD) on gut microbiota and the metabolic profile of epileptic rats.

MATERIALS AND METHODS AND RESULTS

A temporal lobe epilepsy rat model was established using Li-pilocarpine. CBD increased the incubation period and reduced the epileptic state in rats. Compared to epileptic rats, the M1/M2 ratio of microglia in the CBD group was significantly decreased. The expression of IL-1β, IL-6, and TNF-α in the CBD group decreased, while IL-10, IL-4, and TGF-β1 increased. 16S rDNA sequencing revealed that the ANOSIM index differed significantly between the groups. At the genus level, Helicobacter, Prevotellaceae_UCG-001, and Ruminococcaceae_UCG-005 were significantly reduced in the model group. CBD intervention attenuated the intervention effects of Li-pilocarpine. Roseburia, Eubacterium_xylanophilum_group, and Ruminococcus_2 were strongly positively correlated with proinflammatory cytokine levels. CBD reversed dysregulated metabolites, including glycerophosphocholine and 4-ethylbenzoic acid.

CONCLUSION

CBD could alleviate the dysbiosis of gut microbiota and metabolic disorders of epileptic rats. CBD attenuated Epilepsy in rats might be related to gut microbial abundance and metabolite levels.

SIGNIFICANCE AND IMPACT OF STUDY

The study may provide a reliable scientific clue to explore the regulatory pathway of CBD in alleviating Epilepsy.

Transcription factors are potential therapeutic targets in epilepsy

Academics generally believe that imbalance between excitation and inhibition of the nervous system is the root cause of epilepsy. However, the aetiology of epilepsy is complex, and its pathogenesis remains unclear. Many studies have shown that epilepsy is closely related to genetic factors. Additionally, the involvement of a variety of tumour‐related transcription factors in the pathogenesis of epilepsy has been confirmed, which also confirms the heredity of epilepsy. In this review, we summarize the existing research on a variety of transcription factors and epilepsy and present relevant evidence related to transcription factors that may be targets in epilepsy. This information is of great significance for revealing the in‐depth molecular and cellular mechanisms of epilepsy.

Modulation of Microglia M2 Polarization and Alleviation of Hippocampal Neuron Injury By MiR-106b-5p/RGMa in a Mouse Model of Status Epilepticus

MicroRNAs (miRNAs) regulate gene expression at the post-transcriptional level. The miRNA miR-106b-5p has been linked to epilepsy, but its specific role and mechanism of action remain unclear. This was investigated in the present study using a mouse model of pilocarpine-induced status epilepticus and an in vitro system of HT22 hippocampal cells treated with Mg²⁺-free solution and cocultured with BV2 microglia cells. We found that inhibiting miR-106b-5p expression promoted microglia M2 polarization, reduced the inflammatory response, and alleviated neuronal injury. These effects involved modulation of the repulsive guidance molecule A (RGMa)-Rac1-c-Jun N-terminal kinase (JNK)/p38-mitogen-activated protein kinase (MAPK) signaling axis. Our results suggest that therapeutic strategies targeting miR-106b-5p or downstream factors can be effective in preventing epileptogenesis or treating epilepsy.

Soluble Epoxide Hydrolase as a Therapeutic Target for Neuropsychiatric Disorders

It has been found that soluble epoxide hydrolase (sEH; encoded by the EPHX2 gene) in the metabolism of polyunsaturated fatty acids (PUFAs) plays a key role in inflammation, which, in turn, plays a part in the pathogenesis of neuropsychiatric disorders. Meanwhile, epoxy fatty acids such as epoxyeicosatrienoic acids (EETs), epoxyeicosatetraenoic acids (EEQs), and epoxyeicosapentaenoic acids (EDPs) have been found to exert neuroprotective effects in animal models of neuropsychiatric disorders through potent anti-inflammatory actions. Soluble expoxide hydrolase, an enzyme present in all living organisms, metabolizes epoxy fatty acids into the corresponding dihydroxy fatty acids, which are less active than the precursors. In this regard, preclinical findings using sEH inhibitors or Ephx2 knock-out (KO) mice have indicated that the inhibition or deficiency of sEH can have beneficial effects in several models of neuropsychiatric disorders. Thus, this review discusses the current findings of the role of sEH in neuropsychiatric disorders, including depression, autism spectrum disorder (ASD), schizophrenia, Parkinson’s disease (PD), and stroke, as well as the potential mechanisms underlying the therapeutic effects of sEH inhibitors.

Anti-Epileptic Effect of Crocin on Experimental Temporal Lobe Epilepsy in Mice

Temporal lobe epilepsy (TLE) is a common kind of refractory epilepsy. More than 30% TLE patients were multi-drug resistant. Some patients may even develop into status epilepticus (SE) because of failing to control seizures. Thus, one of the avid goals for anti-epileptic drug development is to discover novel potential compounds to treat TLE or even SE. Crocin, an effective component of Crocus sativus L., has been applied in several epileptogenic models to test its anti-epileptic effect. However, it is still controversial and its effect on TLE remains unclear. Therefore, we investigated the effects of crocin on epileptogenesis, generalized seizures (GS) in hippocampal rapid electrical kindling model as well as SE and spotaneous recurrent seizure (SRS) in pilocarpine-induced TLE model in ICR mice in this study. The results showed that seizure stages and cumulative afterdischarge duration were significantly depressed by crocin (20 and 50 mg/kg) during hippocampal rapid kindling acquisition. And crocin (100 mg/kg) significantly reduced the incidence of GS and average seizure stages in fully kindled animals. In pilocarpine-induced TLE model, the latency of SE was significantly prolonged and the mortality of SE was significantly decreased by crocin (100 mg/kg), which can also significantly suppress the number of SRS. The underlying mechanism of crocin may be involved in the protection of neurons, the decrease of tumor necrosis factor-α in the hippocampus and the increase of brain derived neurotrophic factor in the cortex. In conclusion, crocin may be a potential and promising anti-epileptic compound for treatment of TLE.

Total Triterpenes of Wolfiporia cocos (Schwein.) Ryvarden & Gilb Exerts Antidepressant-Like Effects in a Chronic Unpredictable Mild Stress Rat Model and Regulates the Levels of Neurotransmitters, HPA Axis and NLRP3 Pathway

Purpose:Wolfiporia cocos is frequently used in traditional Chinese medicine to treat depression. However, antidepressant-like effects of the main active ingredients of Wolfiporia cocos, total triterpenes of Wolfiporia cocos (TTWC), are not well studied. This study aimed to investigate those effects and explore their specific mechanisms of action in depth.

Methods: Chemical components of TTWC were analyzed using LC-MS. Depression-like behavior in rats were induced by chronic unpredictable mild stress (CUMS). The suppressive effects of TTWC (60, 120, 240 mg/kg) against CUMS-induced depression-like behavior were evaluated using the forced swimming test (FST), open field test (OFT) and sucrose preference test (SPT). Levels of 5-hydroxytryptamine (5-HT), glutamate (GLU), corticotropin-releasing hormone (CRH), interleukin-1 beta (IL-1beta), interleukin-18 (IL-18), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) in different groups were determined by ELISA. Western blotting (WB) was used to detect the expression of NLRP3, ASC, pro-caspase-1, caspase-1, pro-IL-1beta, IL-1beta, pro-IL-18, and IL-18 in the prefrontal cortex. Additionally, the mRNA levels of NLRP3, ASC, caspase-1, IL-1beta and IL-18 were detected by RT-PCR.

Results: A total of 69 lanostane-type triterpene acids of TTWC were identified. The results showed that TTWC exhibited an antidepressant-like effect in CUMS rats, reversed the decreased sugar preference in the SPT, reduction of immobility time in the FST, reduced the rest time, increased the total moving distance in the OFT. TTWC increased 5-HT levels and decreased GLU levels in the hippocampus. Moreover, TTWC decreased CRH levels in serum, indicating the regulation of over-activation of the hypothalamic-pituitary-adrenal (HPA) axis. In addition, reduced serum levels of IL-1beta, IL-18, IL-6, and TNF-alpha. The WB results implied that TTWC inhibited the expression of NLRP3, ASC, caspase-1, IL-1beta, and IL-18 in the prefrontal cortex and enhanced the expression of pro-caspase-1, pro-IL-1beta, and pro-IL-18. Although most of the results were not significant, PCR results showed that TTWC inhibited the expression of NLRP3, ASC, caspase-1, IL-1beta, and IL-18 in the prefrontal cortex.

Conclusion: TTWC treatment exerted an antidepressant-like effect and regulates neurotransmitters, HPA axis and NLRP3 signaling pathway. These results indicated the potential of TTWC in preventing the development of depression.

Epoxyeicosatrienoic acids and soluble epoxide hydrolase in physiology and diseases of the central nervous system

Epoxyeicosatrienoic acids (EETs) are fatty acid signaling molecules synthesized by cytochrome P450 epoxygenases from arachidonic acid. The biological activity of EETs is terminated when being metabolized by soluble epoxide hydrolase (sEH), a process that serves as a key regulator of tissue EETs levels. EETs act through several signaling pathways to mediate various beneficial effects, including anti-inflammation, anti-apoptosis, and anti-oxidation with relieve of endoplasmic reticulum stress, thereby sEH has become a potential therapeutic target in cardiovascular disease and cancer therapy. Enzymes for EET biosynthesis and metabolism are both widely detected in both neuron and glial cells in the central nervous system (CNS). Recent studies discovered that astrocyte-derived EETs not only mediate neurovascular coupling and neuronal excitability by maintaining glutamate homeostasis but also glia-dependent neuroprotection. Genetic ablation as well as pharmacologic inhibition of sEH has greatly helped to elucidate the physiologic actions of EETs, and maintaining or elevating brain EETs level has been demonstrated beneficial effects in CNS disease models. Here, we review the literature regarding the studies on the bioactivity of EETs and their metabolic enzyme sEH with special attention paid to their action mechanisms in the CNS, including their modulation of neuronal activity, attenuation of neuroinflammation, regulation of cerebral blood flow, and improvement of neuronal and glial cells survival. We further reviewed the recent advance on the potential application of sEH inhibition for treating cerebrovascular disease, epilepsy, and pain disorder.

TPPU Pre-Treatment Rescues Dendritic Spine Loss and Alleviates Depressive Behaviours during the Latent Period in the Lithium Chloride-Pilocarpine-Induced Status Epilepticus Rat Model

Epileptogenesis may be responsible for both of recurrent seizures and comorbid depression in epilepsy. Disease-modifying treatments targeting the latent period before spontaneous recurrent seizures may contribute to the remission of seizures and comorbid depression. We hypothesized that pre-treatment with 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU), a soluble epoxide hydrolase (sEH) inhibitor, which has anti-inflammatory and neuroprotective effects might rescue status epilepticus (SE)-induced dendritic spine loss and alleviate depressive behaviours. Rats were either pre-treated with TPPU (0.1 mg/kg/d) intragastrically or with vehicle (40% polyethylene glycol 400) from 7 days before to 7 days after SE that was induced with lithium chloride and pilocarpine intraperitoneally. Rats in the Control group were given saline instead. The forced swim test (FST) was performed on the 8th day after SE to evaluate the depression-like behaviours in rats. The results showed that seizures severity during SE was significantly decreased, and the immobility time during FST was significantly increased through TPPU pre-treatment. Moreover, pre-treatment with TPPU attenuated inflammations including microglial gliosis and the level of proinflammatory cytokine IL-1β in the hippocampus; in addition, neuronal and dendritic spine loss in the subfields of hippocampus was selectively rescued, and the expression of NR1 subunit of N-methyl-D-aspartate (NMDA) receptor, ERK1/2, CREB, and their phosphorylated forms involved in the dendritic spine development were all significantly increased. We concluded that pre-treatment with TPPU attenuated seizures severity during SE and depressive behaviours during the period of epileptogenesis probably by rescuing dendritic spine loss in the hippocampus.

Long-term variable photoperiod exposure impairs the mPFC and induces anxiety and depression-like behavior in male wistar rats

Long-term shift work can cause circadian misalignment, which has been linked to anxiety and depression. However, the associated pathophysiologic changes have not been described in detail, and the mechanism underlying this association is not fully understood. To address these points, we used a rat model of CM induced by long-term variable photoperiod exposure [L-VP] (ie, for 90 days). We compared the numbers of neurons, astrocytes, and dendritic spines; dendrite morphology; long-term potentiation (LTP), long-term depression (LTD) and paired-pulse ratio (PPR); expression of glutamate receptor [N-methyl-d-aspartate receptor (NMDAR) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)] subunits and brain-derived neurotrophic factor (BDNF) in the medial prefrontal cortex (mPFC); and the anxiety and depression behaviors between rats in the circadian misalignment (CM) and circadian alignment (CA, with normal circadian rhythm) groups. The results showed that L-VP reduced the number of neurons and astrocytes in the mPFC and decreased the number of dendritic spines, dendrite complexity, LTP, LTD, PPR, and expression of glutamate receptors (GluR1, GluR2, GluR3, NMDAR2A, and NMDAR2B) and BDNF in the mPFC. L-VP also induced anxiety and depression-like behaviors, as measured by the open field test, elevated plus-maze, sucrose preference test, and forced swim test. These results suggest that CM induces a loss of neurons and astrocytes and synaptic damage in surviving pyramidal cells in the mPFC might be involved in the pathophysiology of anxiety and depression.

Neuroprotective Effect of Fisetin Through Suppression of IL-1R/TLR Axis and Apoptosis in Pentylenetetrazole-Induced Kindling in Mice

Epilepsy is a complex neurological disorder, characterized by frequent electrical activity in brain regions. Inflammation and apoptosis cascade activation are serious neurological sequelae during seizures. Fisetin (3, 3',4',7-tetrahydroxyflavone), a flavonoid molecule, is considered for its effective anti-inflammatory and anti-apoptotic properties. This study investigated the neuroprotective effect of fisetin on experimental epilepsy. For acute studies, increasing current electroshock (ICES) and pentylenetetrazole (PTZ)-induced seizure tests were performed to evaluate the antiseizure activity of fisetin. For the chronic study, the kindling model was established by the administration of PTZ in subconvulsive dose (25 mg/kg, i.p.). Mice were treated with fisetin (5, 10, and 20 mg/kg, p.o.) to study its probable antiseizure mechanism. The kindled mice were evaluated for seizure scores. Their hippocampus and cortex were assessed for neuronal damage, inflammation, and apoptosis. Histological alterations were observed in the hippocampus of the experimental mice. Levels of high mobility group box 1 (HMGB1), Toll-like receptor-4 (TLR-4), interleukin-1 receptor 1 (IL-1R1), interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were assessed in the hippocampus and cortex by ELISA. The immunoreactivity and mRNA expressions of nuclear factor-κB (NF-κB), cyclooxygenase-2 (COX-2), cytochrome C, and caspase-3 were quantified by immunohistochemical analysis and real-time PCR. Phosphorylation ELISA was performed to evaluate AkT/mTOR (mammalian target of rapamycin) activation in the hippocampus and cortex of the kindled mice. The results showed that fisetin administration increased the seizure threshold current (STC) in the ICES test. In PTZ-induced seizures, fisetin administration increased the latency for myoclonic jerks (MJs) and generalized seizures (GSs). In the PTZ-induced kindling model, fisetin administration dose-dependently suppressed the development of kindling and the associated neuronal damage in the experimental mice. Further, fisetin administration ameliorated kindling-induced neuroinflammation as evident from decreased levels of HMGB1, TLR-4, IL-1R1, IL-1β, IL-6, and TNF-α in the hippocampus and cortex of the kindled mice. Also, the immunoreactivity and mRNA expressions of inflammatory molecules, NF-κB, and COX-2 were decreased with fisetin administration in the kindled animals. Decreased phosphorylation of the AkT/mTOR pathway was reported with fisetin administration in the hippocampus and cortex of the kindled mice. The immunoreactivity and mRNA expressions of apoptotic molecules, cytochrome C, and caspase-3 were attenuated upon fisetin administration. The findings suggest that fisetin shows a neuroprotective effect by suppressing the release of inflammatory and apoptosis molecules and attenuating histological alterations during experimental epilepsy.

Metabolic Changes in Rat Plasma After Epilepsy by UPLC-MS/MS

Introduction:

Epilepsy is one of the most common neurological diseases in clinical practice. The combined application of metabolomics technology plays a great advantage in the screening of biomarkers.

Methods:

In this study, Wistar rats were used as experimental subjects to model intractable epilepsy and to detect the metabolic changes of small molecules in plasma. UPLC-MS/MS was used to determine the small molecules in rat plasma. UPLC HSS C18 (2.1mm×100mm, 1.7 μm) column was used for separation, column temperature of 40°C. The initial mobile phase was acetonitrile -0.3% formic acid with gradient elution, the flow rate was 0.3 mL/min, total running time 4.0 min. Quantitative analysis was performed with multi-response monitoring (MRM).

Results:

Compared to the control group, the L-Alanine and L-Arginine decreased in the Epilepsy group (p<0.05); while Cytosine, Adenosine, L-Tyrosine, Citric acid, Fructose increased (p<0.05).

Conclusion:

In the screening of epilepsy biomarkers using metabolomics, various amino acids that lead to increased energy production and neurotransmitter imbalance play an important role in epileptic seizures.

Chronically altered NMDAR signaling in epilepsy mediates comorbid depression

Depression is the most common psychiatric comorbidity of epilepsy. However, the molecular pathways underlying this association remain unclear. The NMDA receptor (NMDAR) may play a role in this association, as its downstream signaling has been shown to undergo long-term changes following excitotoxic neuronal damage. To study this pathway, we used an animal model of fluoxetine-resistant epilepsy-associated depression (EAD). We determined the molecular changes associated with the development of depressive symptoms and examined their response to various combinations of fluoxetine and a selective neuronal nitric oxide synthase inhibitor, 7-nitroindazole (NI). Depressive symptoms were determined using the forced swim test. Furthermore, expression and phosphorylation levels of markers in the ERK/CREB/ELK1/BDNF/cFOS pathway were measured to determine the molecular changes associated with these symptoms. Finally, oxidative stress markers were measured to more clearly determine the individual contributions of each treatment. While chronic fluoxetine (Flxc) and NI were ineffective alone, their combination had a statistically significant synergistic effect in reducing depressive symptoms. The development of depressive symptoms in epileptic rats was associated with the downregulation of ERK2 expression and ELK1 and CREB phosphorylation. These changes were exactly reversed upon Flxc + NI treatment, which led to increased BDNF and cFOS expression as well. Interestingly, ERK1 did not seem to play a role in these experiments. NI seemed to have augmented Flxc’s antidepressant activity by reducing oxidative stress. Our findings suggest NMDAR signaling alterations are a major contributor to EAD development and a potential target for treating conditions associated with underlying excitotoxic neuronal damage.

PET imaging of soluble epoxide hydrolase in non-human primate brain with [18F]FNDP

Purpose

Soluble epoxide hydrolase (sEH) is a promising candidate positron emission tomography (PET) imaging biomarker altered in various disorders, including vascular cognitive impairment (VCI), Alzheimer’s disease (AD), Parkinson’s disease (PD), stroke, and depression, known to regulate levels of epoxyeicosatrienoic acids (EETs) and play an important role in neurovascular coupling. [¹⁸F]FNDP, a PET radiotracer for imaging sEH, was evaluated through quantitative PET imaging in the baboon brain, radiometabolite analysis, and radiation dosimetry estimate.

Methods

Baboon [¹⁸F]FNDP dynamic PET studies were performed at baseline and with blocking doses of the selective sEH inhibitor AR-9281 to evaluate sEH binding specificity. Radiometabolites of [¹⁸F]FNDP in mice and baboons were measured by high-performance liquid chromatography. Regional brain distribution volume (V_T) of [¹⁸F]FNDP was computed from PET using radiometabolite-corrected arterial input functions. Full body distribution of [¹⁸F]FNDP was studied in CD-1 mice, and the human effective dose was estimated using OLINDA/EXM software.

Results

[¹⁸F]FNDP exhibited high and rapid brain uptake in baboons. AR-9281 blocked [¹⁸F]FNDP uptake dose-dependently with a baseline V_T of 10.9 ± 2.4 mL/mL and a high-dose blocking V_T of 1.0 ± 0.09 mL/mL, indicating substantial binding specificity (91.70 ± 1.74%). The V_ND was estimated as 0.865 ± 0.066 mL/mL. The estimated occupancy values of AR-9281 were 99.2 ± 1.1% for 1 mg/kg, 88.6 ± 1.3% for 0.1 mg/kg, and 33.8 ± 3.8% for 0.02 mg/kg. Murine biodistribution of [¹⁸F]FNDP enabled an effective dose estimate for humans (0.032 mSv/MBq). [¹⁸F]FNDP forms hydrophilic radiometabolites in murine and non-human primate plasma. However, only minute amounts of the radiometabolites entered the animal brain (< 2% in mice).

Conclusions

[¹⁸F]FNDP is a highly sEH-specific radiotracer that is suitable for quantitative PET imaging in the baboon brain. [¹⁸F]FNDP holds promise for translation to human subjects.

Betahistine, prevents kindling, ameliorates the behavioral comorbidities and neurodegeneration induced by pentylenetetrazole

A seizure may occur because of the imbalance between glutamate and gamma-aminobutyric acid (GABA). Recurrent seizures induce some cognitive problems, such as, depression, learning and memory deficits, and neurodegeneration. Histamine is an appropriate therapeutic target for epilepsy via its effect on regulating neurotransmitter release. Also, evidence indicates the effect of histamine on neuroprotection and alleviating cognitive disorders. An ideal antiepileptic drug is a substance, which has both anticonvulsant effects and decreases the comorbidities that are induced by repeated seizures. Betahistine dihydrochloride (betahistine) is a structural analog of histamine. It acts as histamine H1 receptor agonist and H3 receptor antagonist, which enhances histaminergic neuronal activities. In the present study, we examined the effect of betahistine administration on seizure scores, memory deficits, depression, and neuronal loss induced by pentylenetetrazole (PTZ). Eight- to ten-week-old BALB/c male mice (20-25 g) received betahistine, 1, and 10 mg/kg daily from 7 days before the onset of PTZ-induced kindling until the end of the establishment of the kindling. We found that betahistine prevented generalized tonic-clonic seizures induction and diminished forelimb clonic seizures intensity. Also, it decreased cell death in the hippocampus and cortex, ameliorated the memory deficit and depression induced by PTZ in the kindled animals. Altogether, these results indicate that pretreatment and repetitive administration with betahistine exerts antiepileptogenic and anticonvulsant activity. These findings might be due to the neuroprotective impact of betahistine in the hippocampus and cortex.