Pentylenetetrazole-induced Seizures Research Articles

Garlic passion fruit (Passiflora tenuifila Killip): Assessment of eventual acute toxicity, anxiolytic, sedative, and anticonvulsant effects using in vivo assays.

Several Passiflora species are known for their sedative and anxiolytic properties. However, the functional properties of Passiflora tenuifila Killip are still unexplored. The objective of this work was to evaluate the phenolic composition and acute toxicity, anxiolytic, sedative, and anticonvulsant effects using in vivo assays. The whole fruit (peel, pulp, and seed) was lyophilized and used for all assays. LC-MS showed 19 phenolic compounds, tentatively identified as flavonoids and phenolic acids. Acute treatment with single doses of up to 2000mg kg-1 in Wistar rats showed no signs of mortality or toxicity over 14days. The assay of functional effects was performed with Swiss mice, four groups, received by gavage, doses of P. tenuifila (200 or 400mg kg-1 body weight), water, and diazepam (as negative and positive control), and behavior tests were performed after 60min of the treatments. The animals treated with P. tenuifila fruit showed a significant decrease in locomotor activity, indicating a sedative and anxiolytic activity. No significant changes were observed in the rotarod apparatus, suggesting that the P. tenuifila fruit did not cause muscle relaxation. The 400mg kg-1 dose of P. tenuifila exerted a protective effect against pentylenetetrazole-induced seizures, decreasing the severity and not causing the death of the animals. In conclusion, P. tenuifila showed no acute toxicity and had a promising effect as an anxiolytic agent, hypnotic-sedative and anticonvulsant, which could be related to its composition of flavonoids and phenolic acids.

Methylene blue protects against pentylenetetrazole-induced seizures, oxidative stress, and neuronal injury

Methylene blue (MethyB) was shown to protect against different brain pathologies. In this study, the effect of acute administration of MethyB on epileptic seizures, brain oxidative stress, and neuronal injury induced in rats by pentylenetetrazole (PTZ) was studied. Rats received repeated intraperitoneal (i.p.) injections of PTZ until the development of status epilepticus and were i.p. treated once with MethyB at doses of 50 or 100 mg/kg, 30 min prior to the first PTZ injection. Results indicated that compared with the PTZ control group, the administration of MethyB at 50 and 100 mg/kg decreased the mean seizure score over the study period by 48.8% and 55.1%, respectively. The development of myoclonic jerks and generalized tonic-clonic seizures was inhibited by 90.0–85.0% and 45.4–56.3%, respectively, compared with the PTZ control group. The mean latency to develop status epilepticus increased by 43.1% after treatment with MethyB at 100 mg/kg. MethyB had no significant effect on the mean threshold dose of PTZ required to reach status epilepticus. MethyB showed inhibitory effects on the increase in brain lipid peroxidation (malondialdehyde), and nitric oxide induced PTZ by 16.7–24.0% and 25.2–32.6%, respectively. Meanwhile, the decrease in reduced glutathione and paraoxonase-1 (PON-1) activity and the increase in nuclear factor-kappa B (NF-κB) in the brain of PTZ-treated rats were attenuated by MethyB. Brain acetylcholinesterase (AChE) concentration decreased by PTZ and showed further decrements after treatment with either dose of MethyB. PTZ caused neuronal atrophy in the hippocampus and cerebral cortex and decreased neuronal size and number in the substantia nigra. These pathological changes were prevented by MethyB given at 100 mg/kg. These data indicate that treatment with MethyB inhibits the PTZ-induced seizures in rats and increases the latency to develop status epilepticus. In addition, MethyB decreases brain oxidative stress and protects against neuronal atrophy in this experimental model of generalized epilepsy.

Embelin Protects Against Acute Pentylenetetrazole-Induced Seizures and Positively Modulates Cognitive Function in Adult Zebrafish.

Purpose of the research: Epilepsy is a continuous process of neurodegeneration categorized by an enduring tendency to generate uncontrolled electrical firing known as seizures causing involuntary movement all over the body. Cognitive impairment and behavioral disturbances are among the more alarming co-morbidities of epilepsy. Anti-epileptic drugs (AEDs) were found to be successful in controlling epilepsy but are reported to worsen cognitive status in patients. Embelin (EMB) is a benzoquinone derived from the plant Embelia ribes and is reported to have central nervous system (CNS) activity. This study aims to evaluate the effectiveness of EMB against pentylenetetrazole (PTZ) induced acute seizures and its associated cognitive dysfunction. This was done via docking studies as well as evaluating neurotransmitter and gene expression in the zebrafish brain. The principal results: Behavioral observations showed that EMB reduced epileptic seizures and the T-maze study revealed that EMB improved the cognitive function of the fish. The docking study of EMB showed a higher affinity toward gamma-aminobutyric acid (GABAA) receptor as compared to the standard diazepam, raising the possibility of EMB working via the alpha subunit of the GABA receptor. EMB was found to modulate several genes, neurotransmitters, and also neuronal growth, all of which play an important role in improving cognitive status after epileptic seizures. Healthy zebrafish treated with EMB alone were found to have no behavioral and biochemical interference or side effects. The immunohistochemistry data suggested that EMB also promotes neuronal protection and neuronal migration in zebrafish brains. Major Conclusions: It was perceived that EMB suppresses seizure-like behavior via GABAA receptor pathway and has a positive impact on cognitive functions. The observed effect was supported by docking study, T-maze behavior, neurotransmitter and gene expression levels, and immunohistology study. The apparatus such as the T-maze and seizure scoring behavior tank were found to be a straightforward technique to score seizure and test learning ability after acute epileptic seizures. These research findings suggest that EMB could be a promising molecule for epilepsy induced learning and memory dysfunction.

Novel effect of Arthrocen (avocado/soy unsaponifiables) on pentylenetetrazole-induced seizure threshold in mice: Role of GABAergic pathway

Arthrocen, an avocado/soy unsaponifiable (ASU)-containing agent, is now used in the clinic and has potentially to decrease joint inflammation and pain associated with mild to severe osteoarthritis. Phytosterols are the major component of Arthrocen with documented anti-inflammatory properties, antioxidant, and analgesic effects.Here, we evaluated ASU anticonvulsant effect by its oral administration in pentylenetetrazole (PTZ)-induced seizure threshold and Maximal Electroshock Seizure (MES) Models. Also, the involvement of N-methyl-d-aspartate (NMDA) receptor, benzodiazepine receptor, and nitric oxide (NO) pathway were studied in anticonvulsant effect of ASU in male NMRI mice. Acute administration of Arthrocen (150, 75, 30, 10 mg/kg) by oral gavage significantly (p < 0.001) increased the clonic seizure threshold induced by intravenous administration of PTZ. Nonspecific inducible NO synthase (NOS) inhibitor L-NAME (10 mg/kg) and a specific NMDA receptor antagonist MK-801 (0.05 mg/kg) did not affect the anticonvulsant effect of Arthrocen, while pretreatment with flumazenil (0.25 mg/kg), a selective benzodiazepine receptor antagonist, reversed this effect (p < 0.01). Also, Arthrocen treated mice did not affect tonic hindlimb extension in the MES model. The data showed that Arthrocen might produce its anticonvulsant effect by enhancing GABAergic neurotransmission and/or action in the brain.

Neuropharmacological effects of d-pinitol and its possible mechanisms of action.

The aim was to evaluate the diuretic and neuropharmacological actions of d-pinitol and describe a possible mechanism of action. The diuretic effects of d-pinitol were evaluated using mice placed in metabolic cages. The sedative, anxiolytic-like, antidepressant-like, and anticonvulsant effects of 1-100mg/kg d-pinitol were assessed. The possible mechanisms of action of the anxiolytic-like, antidepressant-like, and anticonvulsant effects of d-pinitol were evaluated using inhibitors. d-pinitol lacked diuretic effects. However, d-pinitol showed the highest anxiolytic-like actions (ED50 =70mg/kg p.o. in mice) in the cylinder exploratory test and the highest antidepressant-like activity in the forced swimming test (ED50 =26mg/kg p.o. in mice). d-pinitol (100mg/kg) exerted anticonvulsant actions in the pentylenetetrazole-induced seizures test. The pre-treatment with 2mg/kg flumazenil reverted the anxiolytic-like actions and the anticonvulsant effects of d-pinitol, whereas the pre-treatment with 1mg/kg yohimbine and 0.05mg/kg prazosin abolished the antidepressant effects of d-pinitol. PRACTICAL APPLICATIONS: d-pinitol (3-O-methyl-d-chiro-inositol) is a polyol found in many fruits, as well as in many members of the Leguminosae and Fabaceae families. The results propose that this compound could contribute in the treatment of anxiety, depression, and convulsions. The findings suggest the possible participation of the GABAergic system in the anxiolytic-like and anticonvulsant actions of d-pinitol, whereas the noradrenergic system is probably involved in the antidepressant effects of d-pinitol. This study provides new information about other pharmacological uses for d-pinitol.

Effect of Captopril on Brain Oxidative Damage in Pentylenetetrazole-Induced Seizures in Mice&lt;br /&gt;

Background: Frequent seizure is followed by overproduction of free radicals and brain oxidative stress. Renin angiotensin system (RAS) has some effects on central nervous system. We designed this research to challenge the effect of captopril as an angiotensin converting enzyme (ACE) inhibitor against brain oxidative stress in pentylenetetrazole (PTZ) -induced seizures in mice. Methods: The groups were including (1) Control (saline); (2) PTZ (100 mg/kg, i.p.), (3-5) PTZ- captopril (Capto) that received three doses of Capto 10, 50 and 100 mg/kg 30 min before PTZ injection. Latency time in the onset minimal clonic seizures (MCS) and generalized tonic-clonic seizures (GTCS) were recorded. The level of malondialdehyde (MDA) and total thiol, as well as superoxide dismutase (SOD) and catalase (CAT) activity in the hippocampus and cortex were measured. Results: All doses of captopril postponed the onset of MCS and GTCS. Accumulation of MDA in the brain tissues of PTZ group was higher than control group, while total thiol content and CAT activity were lower. Pretreatment with captopril (100 mg/kg) diminished MDA concentration compared with PTZ group. Captopril (50 and 100 mg/kg) also increased the level of total thiol groups versus PTZ group. Captopril injection (50 and 100 mg/kg) elevated the activity of SOD and CAT in the brain tissues. In addition captopril administration diminished mortality rate caused by PTZ. Conclusion: Findings demonstrated that convulsions caused by PTZ were followed by oxidative stress status in the brain tissues. Pretreatment with captopril attenuated the effect of PTZ on brain tissue oxidative damage.&lt;br /&gt;

Involvement of peroxisome proliferator-activated receptor γ in anticonvulsant activity of α-asaronol against pentylenetetrazole-induced seizures in zebrafish

In mammals, peroxisome proliferators activated receptors (PPARs), the nuclear hormone receptors, have been reported to be involved in seizure control. Selective agonists and antagonists of PPARs raise seizure thresholds and suppress seizures, respectively. In this study, we evaluated the anticonvulsant effects of α-asaronol, a metabolic product of α-asarone, on pentylenetetrazole (PTZ)-induced seizures in zebrafish and investigated the underlying mechanisms. As a result, α-asaronol ameliorated seizures with increase of seizure latency, as well as decrease of seizure-like behavior, c-fos expression, and abnormal neuronal discharge in a concentration dependent manner. By comparing gene expression profiles of zebrafish undergoing seizures and α-asaronol pretreated zebrafish, we found that α-asaronol attenuate seizures through increase of PPAR γ expression, while PPAR γ antagonist GW9662 inhibit the anti-seizures actions of α-asaronol. Moreover, molecular docking simulation implied the physical interaction between α-asaronol and PPAR γ. The overall results indicated that the anticonvulsant effects of α-asaronol are regulated through PPAR γ-mediated pathway, which shed light on development of α-asaronol as a potential antiepileptic drug. In addition, it is for first time to report that PPAR γ is associated with seizures in zebrafish, supporting previous evidence that zebrafish is a suitable alternative for studying seizures.

Modulatory effects of neuropeptides on pentylenetetrazol-induced epileptic seizures and neuroinflammation in rats.

We aimed to explore the effects of neuropeptides ghrelin, obestatin, and vasoactive intestinal peptide (VIP) on seizures and plasma concentrations of neuroinflammation biomarkers including calcitonin gene-related peptide (CGRP), substance-P (SP), and interleukin-1 beta (IL-1β) in pentylenetetrazol-induced seizures in rats. Ghrelin (80 µg/kg), obestatin (1 µg/kg), VIP (25 ng/kg) or saline were administered to rats intraperitoneally 30 min before pentylenetetrazole (PTZ, 50 mg/kg) injections. Stages of epileptic seizures were evaluated by Racine's scale, and plasma CGRP, SP, and IL-1β concentrations were measured using ELISA. Both obestatin and VIP shortened onset-time of generalized tonic-clonic seizure, respectively, moreover VIP also shortened the onset-time of first myoclonic-jerk induced by PTZ. While PTZ increased plasma CGRP, SP and IL-1β concentrations, ghrelin reduced the increases evoked by PTZ. While VIP further increased PTZ-evoked CGRP levels, it diminished IL-1β concentrations. However, obestatin did not change CGRP, SP, and IL-1β concentrations. Our results suggest that ghrelin acts as an anticonvulsant, obestatin acts as a proconvulsant, and VIP has dual action on epilepsy. Receptors of those neuropeptides may be promising targets for epilepsy treatment.

Loss of tau and Fyn reduces compensatory effects of MAP2 for tau and reveals a Fyn-independent effect of tau on calcium.

Microtubule-associated protein tau associates with Src family tyrosine kinase Fyn and is tyrosine phosphorylated by Fyn. The presence of tyrosine phosphorylated tau in AD and the involvement of Fyn in AD has drawn attention to the tau-Fyn complex. In this study, a tau-Fyn double knockout (DKO) mouse was generated to investigate the role of the complex. DKO mice resembled Fyn KO in novel object recognition and contextual fear conditioning tasks and resembled tau KO mice in the pole test and protection from pentylenetetrazole-induced seizures. In glutamate-induced Ca2+ response, Fyn KO was decreased relative to WT and DKO had a greater reduction relative to Fyn KO, suggesting that tau may have a Fyn-independent role. Since tau KO resembled WT in its Ca2+ response, we investigated whether microtubule-associated protein 2 (MAP2) served to compensate for tau, since the MAP2 level was increased in tau KO but decreased in DKO mice. We found that like tau, MAP2 increased Fyn activity. Moreover, tau KO neurons had increased density of dendritic MAP2-Fyn complexes relative to WT neurons. Therefore, we hypothesize that in the tau KO, the absence of tau would be compensated by MAP2, especially in the dendrites, where tau-Fyn complexes are of critical importance. In the DKO, decreased levels of MAP2 made compensation more difficult, thus revealing the effect of tau in the Ca2+ response.

Anxiolytic and anticonvulsant activity followed by molecular docking study of ceramides from the Red Sea sponge Negombata sp

The chemical investigation of the Red Sea sponge Negombata sp. led to isolation and structure elucidation of five new ceramides N ((2S,3R,4E,8E)-1,3-dihydroxyhexacosa-4,8-dien-2-yl)pentadecanamide (1), N-((2S,3R,E)-1,3-dihydroxynonadec-4-en-2-yl)stearamide (2), N-[(2S,3R,E)-1,3 dihydroxyhexacos-4-en-2-yl]palmitamide (3), N-((2S,3R)-1,3-dihydroxydodecan-2-yl)tetradecanamide (4), N-[(2S,3S,4R)-1,3,4- trihydroxypentadecan-2-yl] palmitamide (5). Structure elucidation was achieved using spectroscopic techniques, including 1D and 2D NMR and HRMS. The isolated ceramides were tested for anti-anxiety action in the elevated plus maze and the light-dark transition box. Mice given diazepam or compounds number 1, 2, 3, and 5 spent longer time in the light area of the light-dark box. However, compound 4 did not produce a similar effect. Similarly, testing anti-anxiety action in the elevated plus maze test showed that the compounds number 2, 3, and 5 or diazepam were able to prolong the open arm time %. Meanwhile, compounds 1 and 4 failed to produce a similar response. In addition, the anticonvulsant action of the ceramides was assessed employing pentylenetetrazole-induced seizures, where some ceramides prolonged the time to death due to pentylenetetrazole in vivo. In silico testing of the isolated ceramides displayed reasonable GABA receptor modulator binding at the benzodiazepines site. Ceramide 1 showed slightly stronger interaction with the GABA receptor over other ceramides which is compatible with the results of their anxiolytic activity.

Ameliorative Effects of Ellagic Acid on Maximal Electroshock and Pentylenetetrazole-Induced Seizures in Mice

Background: Epilepsy is a series of disorders in the central nervous system defined by disruption and abnormality in the electrical activity of the brain. The mechanisms of epilepsy occurrence are not fully determined and the current pharmacological therapeutics have low efficacy and are associated with adverse reactions due to narrow therapeutic indices. Ellagic acid has neuroprotective and antioxidant effects and increases the brain’s GABA levels. Objectives: This study was designed to evaluate the effects of ellagic acid on both maximal electroshock and pentylenetetrazole models of acute seizures in mice. Methods: Ellagic acid was administered at the doses of 25, 50, and 100 mg/kg in the two models of seizures. Results: The results showed that ellagic acid was effective at the lowest dose in the maximal electroshock-induced seizure in mice and the duration of hind limb tonic extension (HLTE) was significantly shorter in this group than in the untreated convulsive group. In the pentylenetetrazole convulsion model, ellagic acid significantly increased the latency to convulsion and Straub tail response. The latencies with ellagic acid were longer in groups treated with ellagic acid 25 mg/kg than with ellagic acid 50 and 100 mg/kg. Conclusions: In conclusion, it seems that ellagic acid has anticonvulsant effects in electroshock and pentylenetetrazole models of convulsion but its effects are attenuated or eliminated at higher doses.

Ferulic acid ameliorates pentylenetetrazol-induced seizures by reducing neuron cell death

To investigate the neuroprotective effect of ferulic acid (FA) in a pentylenetetrazol (PTZ)-induced seizures model in rat, the motor response, spatial learning ability and memory capability of the rats were assessed. Both the antioxidation and anti-apoptosis pathways were also investigated. In this study, male Wistar rats were randomly divided into 3 groups (n = 12 in each group). For 28 days, the rats were administered saline alone (i.p. normal saline, NS group), PTZ (40 mg/kg, i.p., PTZ group) once daily to induce seizures, or FA (i.p. 60 mg/kg) 20 min before being given PTZ (40 mg/kg, i.p., FA + PTZ group) to assess the neuroprotective effect of FA. The motor response of the rats was analysed with the Racine scale. The spatial learning and memory capacity of the rats were assessed by the Morris water maze test. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were measured, and both in situ staining with the DNA-binding bisbenzimide Hoechst 33258 and TUNEL assays were used to assess apoptosis. Western blotting was used to further analyse the expression of Apaf-1, caspase-9, caspase-3, Bcl-2, Bid, Bax, cleaved caspase-3 and cytochrome c. The results showed that compared to the those of the PTZ group, FA pre-treatment significantly (p < 0.01) reduced the Racine scores starting at day 4, prolonged the latency of the onset of seizure at day 28, reduced the escape latency period starting at day 2, increased the frequency of crossing the platform location, increased the SOD activity, reduced the MDA content and apoptosis percentage, and upregulated the Bcl-2 levels whilst downregulating the Bax, cytochrome c, Apaf-1, caspase-9, caspase-3, cleaved caspase-3 and Bid expression levels. This study demonstrated that pre-treatment with FA exerts strong neuroprotective effects by reducing the motor response and by improving spatial learning ability and memory capacity. The neuroprotective effect may be a result of a reduction in neuron cell death that occurs via the antioxidative and anti-apoptotic pathways.

Cilantro leaf harbors a potent potassium channel-activating anticonvulsant.

Herbs have a long history of use as folk medicine anticonvulsants, yet the underlying mechanisms often remain unknown. Neuronal voltage-gated potassium channel subfamily Q (KCNQ) dysfunction can cause severe epileptic encephalopathies that are resistant to modern anticonvulsants. Here we report that cilantro (Coriandrum sativum), a widely used culinary herb that also exhibits antiepileptic and other therapeutic activities, is a highly potent KCNQ channel activator. Screening of cilantro leaf metabolites revealed that one, the long-chain fatty aldehyde (E)-2-dodecenal, activates multiple KCNQs, including the predominant neuronal isoform, KCNQ2/KCNQ3 [half maximal effective concentration (EC50), 60 ± 20 nM], and the predominant cardiac isoform, KCNQ1 in complexes with the type I transmembrane ancillary subunit (KCNE1) (EC50, 260 ± 100 nM). (E)-2-dodecenal also recapitulated the anticonvulsant action of cilantro, delaying pentylene tetrazole-induced seizures. In silico docking and mutagenesis studies identified the (E)-2-dodecenal binding site, juxtaposed between residues on the KCNQ S5 transmembrane segment and S4-5 linker. The results provide a molecular basis for the therapeutic actions of cilantro and indicate that this ubiquitous culinary herb is surprisingly influential upon clinically important KCNQ channels.-Manville, R. W., Abbott, G. W. Cilantro leaf harbors a potent potassium channel-activating anticonvulsant.

Piperine-loaded nanoparticles with enhanced dissolution and oral bioavailability for epilepsy control

Piperine, an alkaloid from black pepper, has demonstrated beneficial effects in central nervous system, especially in epilepsy control. However, its therapeutic application remains limited due to the low aqueous solubility of piperine. Thus, the present study aimed to formulate piperine into a more solubilized form to enhance its oral bioavailability and facilitate its development as a potential anti-epileptic treatment. The nanoprecipitation method was applied to prepare piperine nanoparticles, which were then examined under transmission electron microscopy. A spherical nanosized particle was obtained with small particle size (average particle size 130.20 ± 1.57 nm), narrow size distribution (polydispersity index 0.195 ± 0.002) and efficient entrapment (entrapment efficiency 92.2 ± 2.5%). Compared with the unformulated piperine, nanosized piperine had a much faster dissolution rate with 3 times higher accumulated drug release after 24 h. After oral administration at 3.5 mg/kg in rats, the nanosized piperine formulations could improve its oral bioavailability by 2.7-fold with 16 times higher concentrations in brain at 10 h postdosing. Moreover, the piperine nanoparticles exhibited effective protection against pentylenetetrazol-induced seizures in both zebrafish and mice. In summary, the present study provided a simple formulation strategy for oral administration of piperine to overcome its limitation in water solubility. The developed formulations could effectively enhance oral bioavailability of piperine with promising anti-epileptic effect, which could be applied as a potential therapy in epilepsy control.

The anticonvulsant effects of salmon calcitonin on pentylenetetrazole-kindled rats

Epilepsy is a disorder of the brain, characterized by an enduring predisposition for the generation of epileptic seizures because of hyperexcitability and hypersynchrony of cortical neurons (Devinsky et al. 2014). Salmon calcitonin is a type of calcitonin with 32 amino acids. It is more potency than human calcitonin due to differences in its amino acid sequence (Masi et al. 2007). In the current study, we investigated the effects of salmon calcitonin on pentylenetetrazoleinduced seizures in kindled rats. In our study, 48 (240-260 g) male Wistar Albino rats were used. Rats were kindled by injections of a subconvulsant dose of pentylenetetrazole (35 mg/kg) once every other day for 15 times. Epileptic behaviors were observed for a period of 30 min. Seizure activity was scored, using the revised Racine’s scale. Rats that had seizure stages of 4 or 5 after three consecutive injections of PTZ were defined as fully kindled.&amp;nbsp; The kindled rats were divided into six groups (n=8 for each group) as saline (1 ml/kg saline), salmon calcitonin (25, 50 and 100 µg/kg), ethosuximide (100 mg/kg) and ethosuximide + salmon calcitonin. Electrodes were placed to animals’ skulls under stereotaxy to receive electroencephalography (EEG). After thirty minutes of administration of drugs, 35 mg/kg PTZ was given to induce seizures. EEG and video recordings of animals were taken simultaneously for thirty minutes. In the evaluation of the video and EEG recordings, the seizure stages of animals, the first myoclonic jerk time and the number of epileptic seizure spikes were calculated.&amp;nbsp;Salmon calcitonin reduced seizures stage, epileptic seizure spikes and also prolonged first myoclonic jerk time compared to saline group. In addition, salmon calcitonin and ethosuximide combination decreased epileptic seizure spikes and increased the first myoclonic jerk time compare to ethosuximide group. In conclusion, salmon calcitonin decreased epileptic seizures and improved anticonvulsant effect of ethosuximide in the pentylentetrazole-kindled rat.&amp;nbsp;

Proteome Based de novo Sequencing of Novel Conotoxins from Marine Molluscivorous Cone Snail Conus amadis and Neurological Activities of Its Natural Venom in Zebrafish Model.

Conus amadis is a carnivorous snail found abundantly in coastal waters of India. Despite its abundance in southern coastal waters of India and the fact that most of the conotoxin act in neuronal system, research work on Conus amadis venom was not much focused. So we have made a brief study on the venom complex of Conus amadis to identify the library of novel conotoxins and to screen the natural venom for neurological function. De novo sequencing of novel conopeptides from the venom cocktail of Conus amadis and to screen its natural venom for the presence of biological activities in zebrafish model. Proteome based MALDI-TOF and LC-MS-MS analysis for identification of novel conotoxins and subsequent sequencing. Due to the complex disulfide rich nature of the venom peptides, the study also involves global chemical modification experiments of the venom extract to unambiguously determine the sequence of novel conotoxins. Biological function analysis of natural venom was tested in zebrafish model to ascertain anti-epileptic properties. In this study, we have identified 19 novel conotoxins containing 1, 2 & 3 disulfides, belonging to different classes. Among them, 2 novel contryphans, 3 T-superfamily conotoxins, 2 A-superfamily conotoxins and 2 Mini M-Superfamily conotoxins were sequenced to its amino acid level from the fragmented spectrum of singly and doubly charged parent ions using de novo sequencing strategies. ama1054, a contryphan peptide toxin, possesses post translationally modified bromo tryptophan at its seventh position. Except ama1251, all the sequenced peptide toxins possess modified C-terminal amidation. Crude venom exhibited anticonvulsant properties in pentylenetetrazole-induced seizure in zebrafish larvae, which suggested anti-epileptic property of the venom cocktail. Acetylcholinesterase activity was also identified in the venom complex. Based on the preliminary evidence, if this study is extended further through bioassay guided purification, could possibly yield peptide toxins with anticonvulsant and other neurologically active molecules.

Galangin Prevents Increased Susceptibility to Pentylenetetrazol-Stimulated Seizures by Prostaglandin E2

Epilepsy is one of the most common chronic neurological diseases. It is characterized by recurrent epileptic seizures, where one-third of patients are refractory to existing treatments. Evidence revealed the association between neuroinflammation and increased susceptibility to seizures since there is a pronounced increase in the expression of key inflammatory mediators, such as prostaglandin E2 (PGE2), during seizures. The purpose of this study was to investigate whether PGE2 increases susceptibility to pentylenetetrazol-induced (PTZ) seizures. Subsequently, we evaluated if the flavonoid isolated from the plant Piper aleyreanum (galangin) presented any anticonvulsive effects. Our results demonstrated that the group treated with PGE2 increased susceptibility to PTZ and caused myoclonic and generalized seizures, which increased seizure duration and electroencephalographic wave amplitudes. Furthermore, treatment with PGE2 and PTZ increased IBA-1 (microglial marker), GFAP (astrocytic marker), 4-HNE (lipid peroxidation marker), VCAM-1 (vascular cell adhesion molecule 1), and p-PKAIIα (phosphorylated cAMP-dependent protein kinase) immunocontent. Indeed, galangin prevented behavioral and electroencephalographic seizures, reactive species production, decreased microglial and astrocytic immunocontent, as well as decreased VCAM-1 immunocontent and p-PKA/PKA ratio induced by PGE2/PTZ. Therefore, this study suggests galangin may have an antagonizing role on PGE2-induced effects, reducing cerebral inflammation and protecting from excitatory effects evidenced by administrating PGE2 and PTZ. However, further studies are needed to investigate the clinical implications of the findings and their underlying mechanisms.

Effect of Culcasia falcifolia on the biogenic amine levels in the brain tissue of pentylenetetrazole induced seizure in mice

In the present study the effect of the ethanol extract of Culcasia falcifolia on the neurotransmitter levels were evaluated. Pentylenetetrazole (PTZ) (60 mg/kg body weight, i. p) was administered to all the groups of mice to induce convulsions. After observing the convulsion, all groups rats were sacrificed, whole brain was dissected out and separated the forebrain. The brain tissue was homogenized and then centrifuged. The aqueous phase was taken for the assay. The reading was obtained using spectroflurimeter. The result of the present study shows that the ethanol extract of Culcasia falcifolia at the dose of 200 and 400 mg/kg body weight significantly increased the level of inhibitory neurotransmitter GABA and also showed significant increase in the levels of dopamine, noradrenalin and serotonin when compared to seizure control group (PTZ treated group) and was almost equivalent to control group. The findings of the study showed that the extract at 200 and 400 mg/kg body weight significantly (p<0.001) increased the levels of GABA, dopamine, serotonin and noradrenaline. The ethanol extract of Culcasia falcifolia exerted antiepileptic activity by decreasing seizure susceptibility to pentylenetetrazole-induced seizure in mice due to restoration of GABA, serotonin, dopamine and noradrenaline concentration levels in mice brain.

Target identification, screening and in vivo evaluation of pyrrolone-fused benzosuberene compounds against human epilepsy using Zebrafish model of pentylenetetrazol-induced seizures

Pyrrolone-fused benzosuberene (PBS) compounds were semi-synthesized from α,β,γ-Himachalenes extracted from the essential oil of Cedrus deodara following amino-vinyl-bromide substituted benzosuberenes as intermediates. These PBSs compounds classified as an attractive source of therapeutics. The α-isoform of PI3K which is a pivotal modulator of PI3K/AKT/mTOR signaling pathway, responsible for neurological disorders like epilepsy, found as a potential target molecule against these 17 semi-synthesized PBS compounds using in silico ligand-based pharmacophore mapping and target screening. The compounds screened using binding affinities, ADMET properties, and toxicity that were accessed by in silico docking simulations and pharmacokinetics profiling. Ultimately two compounds viz., PBS-8 and PBS-9 were selected for further in vivo evaluation using a zebrafish (Danio rerio) model of pentylenetetrazol (PTZ)-induced clonic convulsions. Additionally, gene expression studies performed for the genes of the PI3K/AKT/mTOR pathway which further validated our results. In conclusion, these findings suggested that PBS-8 is a promising candidate that could bedeveloped as a potential antiepileptic.

Synthetic, non-intoxicating 8,9-dihydrocannabidiol for the mitigation of seizures

There can be a fine line between therapeutic intervention and substance abuse, and this point is clearly exemplified in herbal cannabis and its products. Therapies involving cannabis have been the treatment of last resort for some cases of refractory epilepsy, and this has been among the strongest medical justifications for legalization of marijuana. In order to circumvent the narcotic effects of Δ9-tetrahydrocannabinol (THC), many studies have concentrated on its less intoxicating isomer cannabidiol (CBD). However, CBD, like all natural cannabinoids, is a controlled substance in most countries, and its conversion into THC can be easily performed using common chemicals. We describe here the anticonvulsant properties of 8,9-dihydrocannibidiol (H2CBD), a fully synthetic analogue of CBD that is prepared from inexpensive, non-cannabis derived precursors. H2CBD was found to have effectiveness comparable to CBD both for decreasing the number and reducing the severity of pentylenetetrazole-induced seizures in rats. Finally, H2CBD cannot be converted by any reasonable synthetic route into THC, and thus has the potential to act as a safe, noncontroversial drug for seizure mitigation.