Citation: 

Condradsen, I., Wold, P., Sams, T., Sorensen H., Beniczky, S. (2011). Patterns of muscle activation during generalized tonic and tonic-clonic epileptic seizures. Epilepsia, 52(11), 2125-2132.

Summary: This study aimed to explain the way that the muscles in the human body activate/what happens to the muscles during the tonic portion of a tonic-clonic seizure and to determine if muscle activation during tonic seizures is different than muscle activation during normal activities (physiologic). This study used a technique involving surface electromyogram (EMG) which is when electrodes are placed on the muscle outside the skin to track activation rates, in this case, on the deltoids (upper shoulder). It was found that muscle activation presented differently in patients who had GTCS compared to those who had tonic seizures. They recorded seizures in patients who had epilepsy (7 F and 13 M – 24.8) and recorded seizures that were simulated by healthy volunteers (8F and 12 M – 25.4) (age range was 6-54,58). They measured the amplitude (extent of vibration) of the seizures, both real and simulated. There was a significant shift towards higher frequencies in patients who experienced tonic seizures (increased amplitude, which can be contributed to the recruitment of more, high threshold motor neurons). The simulated and actual seizures, although appeared to be similar visually, had different muscle activations.

Results: The tonic phase in GTCS is due to increased amplitude of the seizure signal, while tonic seizures alone are due to a significant increase in the frequency (the rate at which something is repeated) of the seizure signal.

Citation: 

Zhu, G., Wang, J., Xiao, L., Yang, K., Huang, K., Li, B., Huang, S., Hu, B., Xiao, B., Liu, D., Feng, L., Wang, Q. (2021). Memory Deficits in Patients With Temporal Lobe Epilepsy: Evidence From Eye Tracking Technology. Frontiers in Neuroscience, 15:716476.

Summary: 70 percent of patients with TLE have memory dysfunction. 34 TLE patients and 28 healthy controls (males and females) completed neurobehavioral assessments, cognitive oculomotor tasks, and 24 hour EEG recordings with an eye tracker; their results were compared. The tests were two of Wechsler Memory Scales-Chinese Revision (one; verbal memory test, 2; non-verbal, visual short-term memory test). The cognitive oculomotor task was a computer-based memory assessment platform that had game-like interactions (participants wore the Tobii Glass II wearable eye tracker). Patients with TLE took longer than healthy controls to find the target items. Patients also memorized significantly less items than the control group. 

Results: The encoding phase of the experiments were the same for both groups, but the recall phase was worse for patients with TLE (they had retrieval deficits).

Citation:

Lespinet, V., Bresson, C., N'Kaoua, B., Rougier, A., Claverie, B. (2002). Effect of age of onset of temporal lobe epilepsy on the severity and the nature of preoperative memory deficits. Neuropsychologia, 40, 1591-1600.

Summary: Many variables affect the memory deficits that come with TLE, such as age of onset. 56 epileptic patients and 20 healthy controls were used in this study to determine the effect of age of onset on the nature and severity of memory deficits. From these patients, four groups were made: left or right TLE with either early (0-5 years, groups one and two) or late (10 years and over, groups three and four) age of seizure onset. The two tests that were used to measure memory were the Wechsler memory scale-revised and the Rey complex figure. In the WMS-R, subtests were used: logical memory, pair-associated words, visual reproduction, pair-associated figures. In the Rey complex figure, subtests were used: copy, and delayed recall (after 5 minutes of learning).

Results: The most important factor for memory deficits was level of education, and the second most important seemed to be the age of onset of epilepsy. The early group displayed major deficits in verbal and nonverbal memory (very apparent in the story recall and complex figure recall), while the late group showed only minor deficits: verbal deficits with left TLS and nonverbal deficits with right TLS.

Citation:

Roubicek, G., Gonzalez, L., Lah, S., Jackman, A., Harvey, S., Saling, M. (2020). Verbal memory in children with temoral lobe epilepsy: Exploring task-specificity. Epilepsy and Behavior, 111: 107341.

Summary: This study took 38 children and adolescents with lesional TLE, ages 6-16, and measured their arbitrary associative memory using the Verbal Paired Associates subtest, as well as thier semantically related memory. The arbitrary memory test measured their ability to learn and recall two types of word pairs: hard-pairs, meaning words that are often not thought to go together, like cabbage and pen, and easy-pairs, meaning words that often go together, such as rose and flower. The semantically memory test measured by two tasks: semantically related word pairs (learnt and recalled) and prose memory (stories subset). 

Results: Children who had mesial TLE did worse on both types of memory assessment than children who had lateral TLE. This suggests that this adult memory test may not be completely applicapble to children, but never the less, mesial TLE affects memory greater than lateral TLE, at least, as shown in this case study.

Citation:

Postma, T., Cury, C., Baxendale, S., Thompson, P., Cano-Lopex, I., de Tisi, J., Burdett, J., Sidhu, M., Caciagli, L., Winston, G., Vos, S., Thom, M., Duncan, J., Koepp, M., Galovic, M. (2020). Hippocampal Shape Is Associated with Memory Deficits in Temporal Lobe Epilepsy. Annals of Neurology, 88(1), 170-182.

Summary: Participants included 145 patients with medically refractory TLE before they underwent temporal lobe resections, as well as 39 sex and aged matched controls. Verbal and visual memory was assessed both preoperatively and one year postoperatively. Verbal learning was assessed by having each patient read a lost of 15 words 5 times and then being asked to recall thoes words immediately after. To assess visual memory, patients were shown a graphical design five times and asked to recall it after each presentation. MRIs were also taken of the brain, as well as hippocampal segmentations. From these hippocampal segmentations, 3D surface meshes were extraceted and parameterized. These were then compared to the hippocampal segmentations of the healthy controls to look for alignments failures.

Results: Both the right and left TLE patients had lower verbal and visual memory scores than the healthy controls. Right TLE patients had lower visual memory memory scores than left TLE patients. After surgery, verbal memory decline was more common after left compared to right temporal lobe removal.

The ipsalateral hippocampus was smaller in both LTLE and RTLE patients compared to controls and the right hippocamous was larger in LTLE patients than in controls

Hippocampal Shape and Presurgical Memory Results

Degeneration of the left hippocampal head was associated with decreased verbal memory and degeneration of the hippocampal surface was associated with worse visual memory.

Hippocampal Share and Postsurgical Memory Results

Degeneration of the left hippocampal tail was associated with decline in verbal memory one year after anterior left temporal lobe resection.

Citation:

Banjac, S., Roger, E., Cousin, E., Mosca, C., Minotti, L., Krainik, A., Kahane, P., Baciu, M. (2022). Mappong of Language-and-Memory Networks in Patients With Temporal Lobe Epilepsy by Using the GE2REC Protocol. frontiers in Human Neuroscience, 15(752138), 1-22.

Summary: This study included 18 LTLE patients and 19 healthy controls (all patients were diagnosed with drug resistant LTLE). Standardized tests, such as the WAIS, were used to assess the cognitive efficiency of cerebral activated networks. Overall, the LTLE groups had a lower percentage of correct responses in comparrison to the healthy controls. Sentence generation revealed more activation of bilateral inferior frontal opercular, parietal, and left superior temporal cortices in the healthy control compared to the LTLE group. Recognition also activated more the bilateral superior patrietal, occipital, fusiform, and lingual gyri in the healthy controls, as well as more activation in the  right inferior pars oppercularis and insula during the recall phase of the standardized test.

Results: Different parts of the brain are more activated in healthy patients compared to those with TLE, especially when performing everyday tasks, such as those assessed in the WAIS and other standardized tests. Their pathways are also different for language and memory.

Citation: 

Gascoigne, M., Smith, M., Barton, B., Webster, R., Gill, D., Lah, S. (2014). Accelerated long-term forgetting in children with temporal lobe epilepsy. Neuropsychologia, 59, 93-102.

Summary: This study aimed to look at how chromological age and long-term forgetting presents itself in young children, as it has been looked at in adults, but not so much for children. 58 healthy controls and 23 children with TLE completed many neuropsychological tests, such as the learning of words and designs. Their short-term (30 min) recall and long-term (7-day) recall were then assessed.

Results: The TLE group scored more poorly on the word recall after 7 days compared to the short term recall, as well as compared to the healthy controls. Patients with a left-hemisphere seizure focus recalled fewer words at short and long delays, whereas patients with an abnormal hippocampus recalled fewer words only at the long delay. Older age in the patient group was found to be correlated with worse memory, but this conclusion was absent in the control group.

Citation:

Bakhtiari, A., Bjorke, A., Larsson, P., Olsen, K., Naevra, M., Tauboll, E., Heuser, K., Ostby, Y. (2022). Episodic Memory Dysfunction and Effective Connectivity in Adult Patietns With Newly Diagnosed Nonleasional Temporal Lobe Epilepsy. frontiers in Neurology, 13(774532), 1-12.

Summary: This study aimed to look at the changes or connectivity in the brain, detected by EEG, in patients with LTE, as well as to look at episodic memory (information that is linked to a specific place and time). EEGs were performed on all patients to determine their connectivity. To determine the state of their episodic memory, the patients were asked to complete a digital version of The Memory Experiences Questionnaire, which measures the phenomenological characteristics of their episodic memories.

Results: Patients with TLE had decreased episodic memory than healthy controls. The patients also showed a deformity in connectivity in the right parietaofroontal area of the brain, as well as weaker connectivity in their right hemisphere compared to theri left.

Citation:

Kibby, M., Cohen, M., Stanford, L., Park, Y. (2019). Are frontal and temporal lobe epilepsy dissociable in their memory functioning? Epilepsy & Behavior, 99(106487), 1-7.

Summary: 91 children (6-15) who all had focal onset epilepsy. Verbal and nonverbal memory was assessed, as well as short-term memory/learning and long term memory through stories (asked to listen to a story and repeat it), word pairs, dot locations, and faces (12 or 16 faces, presented for 2 seconds and then asked to recall which faces were in the group when mixed with faces not in the original group). This study assessed memory relatively how the other studies assessed memories, only this study was done on children whereas previous studies I've read were done solely on adults.

Results: Children with LTLE performed worse on verbal-short-term memory/learning and long-term memory tests. Children with RTLE performed worse than controls on long-term memory for faces. The main take away is that children with different types of epilepsies have difficulty with memory, but in different areas.

Citation:

Voltzenlogel, V., Després, O., Vignal, JP., Steinhoff, BJ., Kehrli, P., Manning, L. (2006). Remote memory in temporal lobe epilepsy. Epilepsia, 47(8):1329-36.

Summary/Results: Voltzenlogel and others explore remote memory in patients with TLE and look aat the impact certain factors that are often associated with TLE, such as age of onset and seizure frequency, have on those memories. They tested patients with TLE and compared their rememberance of personal and public memories with that of healthy controls. They found that patients with TLE performed worse on autobiographical and public memory tests, but perfomed the same as the healthy controls did when personal memory was assessed. They did determine that there was no influence on memory from age of onset or seizure frequency, which I found to be a little odd, given that I have read other studies that mention these are huge factors in memory recall.

Citation: 

Voltzenlogel, V., Vignal, JP., Hirsch, E., Manning, L. (2014). The influence of seizure frequency on anterograde and remote memory in mesial temporal lobe epilepsy. Seizure, 23(9):792-798.

Summary/Results: The next paper of hers that I looked at was written in 2014 and looked at the influence of seizure frequency on anterograde and remote memroy in mesial temporal lobe epilepsy patients. This is a "zoom-in" from her paper written in 2006, as it looks deeper into the influence of seizure frequency on remote memory. This is a zoom-in because in her first paper, a significant link was not found between frequency of seizure and remote memory. However, in this paper, it was found significant that those patients who experienced high frequencies of seizures performed worse on autobiographical and news-events memory, due to the fact that high frequencies of seizures tend give rise to mesial temporal lobe damage which then in turn affects memory. It was intersting, however, that the frequency of seizure did not, to my and the authors' suprise, affect memory for famous people.

Citation:

Voltzenlogel, V., Ernst, A., de Seze, J., Brassat, D., Manning, L., Berna, F. (2016). Giving meaning to illness: An investigation of self-defining memories in patients with relapsing-reemitting multiple sclerosis patients. Consciousness and Cognition, 45, 200-209.

Sumamry/Resutls: The third paper takes slightly a different approach and moves away from looking at how temporal lobe epilepsy affects memory and instead looks at how memories, specifically self-defining memorries, are affected in patients with relapsing-remitting multiple sclerosis. These patients, along with healthy controls, underwent self-defining memory questionnaires and looked at how MS affected memory and self portrayal. However, the study found that there was no significant differences in how patients with MS and healthy controls report memories about past acheivements. In this paper, it was concluded that MS does not prevent patients from defining themselves and living life and experiencing successful events. I believe in relation to the other two papers, this third paper was a "zoom out" followed by a "zoom in". It just happens that the zoom in meant looking at another neurological disease and seeing how that affected memory, instead of looking at how temporal lobe epilapsy affects memory.

Citation:

Mohammad, F., Singh, P., Sharma, A. (2009). A Drosophila systems model of pentylenetetrazole induced locomotor plasticity responsive to antiepileptic drugs. BMC Systems Biology, 3(11): 1-17.

Summary/Resutls: Seven days of PTZ treatment, followed by a seven day withdrawl in Deosophila caused a decrease and an increase in many locomotor activities like climbing speed, respectively. After PTZ was administered, through food, no convulsive behaviors were observed, but hyperkinetic behaviors were apparent. Those treated with PTZ has decreased directionality (they took a more circuitous path) compared to those in the control.

Citation:

Shimada, T., Yamagata, K. (2018). Pentylenetetrazole-Induced Kindling Mouse Model. Journal of Visualized Experiments, 136: 1-10.

Summary/Resutls:

This paper talks about indicing seizures in mice using PTZ, which is a GABA-A receptor antagonist. Intraperitoneal injection of PTZ incudes and acute severe seizure at a high dose, but sequential injections of a subconvulsive dose have been used for the development of chemical kindling. This paper gives step by step directions on how to use PTZ to induce seizures in mice, as well as how to prepare the PTZ and what doses to give depending on what outcome you want (how severe you want the seizure to be depending on what youre studying). They also give score guidelines to score the seizures based on their observable behaviors. I believe that I am going to use this scoring guidelines in my methods, or one very similar to it. This paper will also be very helpful when constructing my methods for my presentation, as this is the experiment that I want to recreate and add a spin to.

Citation:

Luszczki, J., Wojcik-Cwikla, J., Andres, M., Czuczwar, S. (2005). Pharmacological and Behavioral Characteristics of Interactions between Vigabatrin and Conventional Antiepileptic Drugs in Pentylenetetrazole-Induced Seizures in Mice: An Isobolographic Analysis. Neuropsychopharmacology, 30, 958-973.

Summary/Results: This study looked at the anticonvulsant effects and types of interactions exerted by mixtures of vigabatrin (VGB), and conventional antiepileptic drugs such as valproate (VPA), ethosuximide (ESM), phenobarbital (PB), and clonazepam (CZP) in pentylenetetrazole (PTZ) - induced seizures in mice. After inducing mice with PTZ, they tested many things, such as motor performance, long-term memory, pain sensitivity, and general explorative locomotor activity. This study basically wanted to see if there are other combinations of anticonvulsant drugs that can be used to free patients of seizures, as many patients have allergic reactions or immunity to existing AEDs (antiepileptic drugs).

All experiments were performed on adult male albino Swiss mice weighing 22–26 g. The mice were kept in colony cages with free access to food and tap water ad libitum, under standardized housing conditions (natural light–dark cycle, temperature was 21711C). Group size: 8 mice in each experimental group. Drugs were injected intraperitoneally and were prepared the day of the experiment and administered before seizures and other evaluations. PTZ (Sigma, St Louis, MO, USA) was dissolved in distilled water and administered subcutaneously (s.c.) into a loose fold of skin in the midline of the neck in a volume of 0.005ml/g body weight. Clonic convulsions were induced in mice by s.c. administration of PTZ at the doses ranging between 70 and 120 mg/kg. After injection, they were placed into separate plexiglas cages and observed for 30 minutes to watch for seizures. The clonic seizure activity was defined as the clonus of whole body lasting over 3s, with an accompanying loss of righting reflex. A convulsive dose of PTZ was 1110mg/kg (this amount of PTZ incudes clonic seizures in 97% of mice). The animals were then treated with varying doses of AEDs to find ED50, which is the dosage of each drug that prevented seizures in 50% of the mice in each experimental group.

Citation:

de Castro e Silva, J., Lopes do Couto, L., de Oliveria Amaral, H., Gomes, F., Campos, G., Silva, L., Mortari, M. (2020). Neuropolybin: A new antiseizure peptide obtained from wasp venom. Biochemical Pharmacology, 181.

Summary/Results: The purpose of this study was to determine the potential antiseizure effect of the peptide Ppnp7, which was extracted from the venom of the social wasp Polybia paulista. They wanted to do so because many treatments for epilepsy have harmful side effects and/or are expensive. Arthropod venom seems to be a viable option for epileptic therapy because their compounds are known for their highly selective and potent profiles.

The speciments were collected and immediately frozen. Then their venom sacs were removed (approx. 8000 at -20 deg C) The venom sacs  were then homogenized in 1:1 deionized water and acetonitrile (ACN) and cen- trifuged at 10,000×g for 5 min. The supernatant was collected and ultrafiltered at 10,000×g for 30 min with a 3 kDa Microcon® ultrafilter (Merck KGaA, Germany). The resultant material was vacuum dried, quantified by weight and called LMWC-Pp, since it contains only low molecular weight compounds of the venom of the social wasp P. pau- lista. They then performed liquid chromatography and mass spectrometry analysis. Again, PTZ was used to induce seizures in rats.(n = 5–8): a positive control group treated with Diazepam (DZP, 2 mg/kg, i.p.), a negative control group - vehicle treated with saline solution (0.9% NaCl, i.c.v.), and the experimental group subdivided into four doses of Ppnp7 (15, 3.7, 2.5 and 1.2 nmol/rat, i.c.v.). It was found that Ppnp7, in any given dose, did not affect the general spontaneous activity of the rats in any way.

Citation:

Taiwe, GS., Moto, FCO., Ayissi, ERM., Nhoupaye, GT., Njapdounke, JSK., Nkantchoua, GCN., Kouemou, N., Omam, JPO., Kandeda, AK., Pale, S., Pahaye, D., Ngo Bum, E. (2015). Effects of a lyophilized aqueous extract of Feretia apodanthera Del. (Rubiaceae) on pentylenetetrazole-induced kindling, oxidative stress, and dognitive impairment in mice. Epilepsy & Behavior, 43, 100-108.

Summary/Results: This study aimed to look at the effects of Feretia apodanthera Del. (Rubiaceae), a plant faound mainly in tropical Africa, on PTZ induced kindling, which is seizures. Depending on the dosage, it was found that Rubiaceae has antiseizure effects, such as increased latency to myoclonic jerks, clonic seizures, and generalized tonic-clonic seizures. The stem bark was collected, separated, cleaned, sun-dried, and pulverized by a grinder. The powder was then extracted with distilled water for 24 hours and filtered. It was then freeze-dried and reconstituted in distilled water at the necessary concentrations. Male swiss mice (26-30g) were used. They has access to food and water and maintained a 12 h light-dark cycle. The mice were divided into 8 groups (6 animals each); first group got saline intraperitoneally, second-seventh group were administered PTZ dissolved in saline every second day. One hour before being administered PTZ, the mice in the first and second groups were given distilled water, while the third-sixth groups got varying dosages of the Rubiaceae aqueous extract orally through a feeding tube. PTZ was administered up to day 43, or until stage 5 seizures on two consecutive trials were achieved, Group eight recieved the extract alone to see its effects on cognitive functions, if any. Maze trials were done after and the behaviors of the mice were recorded. Seizure activity was recorded and scored based on these parameters: stage 0: no response; stage 1: hyperactivity and vibrissal twitching; stage 2: head nodding, head clonus, and myoclonic jerk; stage 3: unilateral forelimb clonus; stage 4: rearing with bilateral forelimb clonus; and stage 5: generalized tonic–clonic seizures with loss of righting reflex.

Citation:

Lopes do Couto, L., Carneiro dos Anjos, L., de Azevedo Feitosa Araujo, M., Alves Mourao, C., Alberto Schwartz, C., Brandao Ferreira, L., Renata Mortari, M. (2012). Anticonvulsant and anxiolytic activity of the peptide fraction isolated from the venom of the social wasp Polybia paulista. Pharmacognosy Magazine, 8(32):292-299.

Summary/Results: Took wasp venom to test its affects on seizure activity. P. paulista were collected in Brazil and then euthenized by freezing temperatures. 1,500 vanom sacs were collected and macerated in a 1:1 acetonitrile/deionized water solution. The material was then centrifuged, which led the samples to contain low-molecular-weight compounds of the venom. Male Wistar rats (220-250g) were used and kept in cages with a 12 h light-dark cycle at 22 degrees C. Animals were anesthetized with ketamine and xylazine. A local injection of lidocaine was given and the cranium was exposed for implantation of a guide cannula in the right lateral ventricle (animals then recovered for 5-7 days). The rats were injected intracerevroventricularly with the venom and then 10 minutes later, were injected with a single dose of PTZ and watched for 30 minutes. No significant effects were found from the venom group when compared to the saline group, however, dose-dependent anticonvulsant effects were observed.

Citation:

Mortari, M., Cunha, A., Anjos, L., Amaral, H., Quintanilha, M., Gelfuso, E., Homem-de-Mello, M., de Almeida, H., Rego, S., Maigret, B., Lopes, N., dos Santos, W. (2023).  A new class of peptides from wasp venom: a pathway to antiepileptic/neuroprotective drugs. Brain Communications, 5(1): 1-20.

Summary/Results: This study also looked at the effects of wasp venom on male Wistar rats (220-250g) when induced with seizures, either by kainic acid or PTZ. Venom extracts were collected from female P. occidentalis in Brazil. Wasps were basically frozen to death so thier venom sacs could be removed and centrifuged. Rats underwent intracerebroventricular administration of the venom extract, whereas mice underwent intraperitoneal administration of the peptide. Rats were anesthetized with either ketamine or xylazine for implantation of the guide cannula. The coordinates used were anteropos- terior (AP): 0.9 mm to bregma, mesolateral (ML): 1.6 mm and dorsal–ventral (DV): 3.4 mm ventral from the surface of the skull, according to the Paxinos and Watson’s atlas (1986). The cannula was fixed to the skull with dental acryl- ate and was sealed with stainless-steel wire to avoid obstruction (animals were allowed to recover for 4-6 days after surgery. Rats were divided into groups (4-6) and treated with the peptid by icv injeection in varying dosages. PTZ was then injected subcutaneously in a loose fold in the neck. Control groups for each experimental group were given saline. EEG recordings were taken to watch for seizures. The peptide showed potent antiseizure effects in acute (kainic acid and PTZ) and chronic (TLE induced by pilocarpine) models. However, motor and cognitive behaviors were not affected.

Citation:

Fachim, H., Cunha, A., Pereira, A., Beleboni, R., Gobbo-Neto, L., Lopes, N., Coutinho-Netto, J., dos Santos, W. (2011). Neurobiological activity of Parawixin 10, a novel anticonvulsant compound isolated from Parawixia bistriata spider venom (Araneidae: Araneae). Epilepsy & Behavior, 22(2): 158-164.

Summary/Results: This study aimed to look at the effects of Parawixin 10, venom isolated from Parawixia bistriata (a spider), in neurobiological activity of Wistar rats (200-250g). Like the other studies with rats, a cannula was implanted into the lateral ventricles to perform the experiments and analyses. This study concluded that lower dosages of the spider venom increased the delay of onset of seizure in rats. This study also found that this venom has an effect on the glutamatergic and glycinergic systems.

The spiders were collected in Brazil and were frozen so that glands and venom resivoirs could be removed. The venom was then centrifuged and then submitted for fractionation. Rats were dosed with Parawixin

Citation:

 Heidarli, E., Vatanpour, H., Nasrabadi, N., Soltani, M., Tahmasebi, S., Faizi, M. (2023). The Effects of the Fraction Isolated from Iranian Buthotus shach Scorpion Venom on Synaptic Plasticity, Learning, Memory, and Seizure Susceptibility. Iranian Journal Of Pharmaceutical Research, In Press(In Press).

Summary/Results: This study aimed to look at the effects of fractions of Buthotus shach isolated from an Iranian Scorpion on synaptic plasticity, leanring, memory, and seizure susceptibility. The crude venom from the scorpions was obtained from a research institution in Iran. Fractions were separated using gel filtration. 18 male Wistar rats (250-300g) were separated into three groups (6 rats per group). They underwent surgery and a cannula was placed in the left ventricle of the brain. Venom extractions were administered through the intra-cerebroventricular route. The control groups received saline instead. 30 minutes after the injection, PTZ was administered and tests were done to evaluate effects. The active fraction of the venom could affect the intensity of the induced seizures, as well as the delay of onset of the seizure.

Citation:

Hu, Y., Meng, B., Yin, S., Yang, M., Li, Y., Liu, N., Li, S., Lui, Y., Sun, D., Wang, S., Wang, Y., Fu, Z., Wu, Y., Pang, A., Sun, J., Wang, Y., Yang, X. (2022). Scorpion venom peptide HsTx2 suppressed PTZ-induced seizures in mice via the circ_0001293/miR-8114/TGF-β2 axis. Journal of Neuroinflammation, (19)284: 1-18.

Summary/Results: This study aimed to look at the effects of scorpion venom peptide HsTx2 on PTZ induced seizures in BLAB/c mice (20-22g). The mice were purchased and raised under normal conditions (outlined in the other papers above). Mice were injected i.p. with PTZ once every other day for a total of 10 injections, upon which they were observed for 30 minutes to record seizure activity. Mice that exhibited scores of 4 or 5 were considered fully kindled and then used as model mice for the actual experiment. They were divided into four groups, which were each given an i.p preinjection of PTZ. "Primary astrocyte culture, immunofluorescence staining, RNA sequencing, identification and quantification of mouse circRNAs, cell transfection, bioinformatics and luciferase reporter analyses, enzyme-linked immunosorbent assay, RNA extraction and reverse transcription–quantitative PCR, Western blot and cell viability assays were used to explore the potential mechanism of HsTx2 via the circ_0001293/ miR-8114/TGF-β2 axis," (Hu et. al). They found that the venom peptide did infact exhibit anti-epileptic effect, as well as reduced the inflammatory response.

Citation:

Cairrao, M., Ribeiro, A., Fontana, A., Beleboni, R., Coutinho-Netto, J., Miranda, A., Santos, W. (2002). Anticonvulsant and GABA Uptake Inhibition Properties of Venom Fractions from the Spiders Parawixia bistriata and Scaptocosa raptoria. Pharmaceutical Biology, 40(6): 472-477.

Summary/Results: This study aimed to look at the effects of the venom fractions from the Spiders Parawixia bistriata and Scaptocosa raptoria. Spiders were obtained and the venom resivoirs were removed the same way as in the papers above. Their venoms were then centrifuged, resulting in the denatured forms of the venoms. Male Wistar rats (200-250g) were used and kept under normal light-dark conditions (as described in papers above). A guide cannula was placed in their right laternal ventricle, attached to the skull with acrylic resin and anchored with stainless steel screws. They were allowed 5 days to recover. Microinjections were administered through a 30-gauge stainless steel injection cannula. The injection volume was 2 muliters/2 minutes. Rats were intracerebroventricularly dosed with either saline (control) or the fractions or venoms (experimental groups). They were then dosed with either PTZ, picrotoxin, or bicuculline to induce seizures and watched for 30 minutes to analyze their behavior. It was found that intracerebroventricular injections of both the crude venom and the fractions abolished rat convulsive tonic-clonic seizures, as well as inhibited GABA uptake in synaptosomes of the rat cerebral cortex.

Citation:

Nôga, A., Brandão, E., Cagni, C., Silva, D., de Azevedo, L., Araújo, A., Dos Santos, F., Miranda, A., da Silva, H., Ribeiro, M. (2016). Anticonvulsant Effects of Fractions Isolated from Dinoponera quadriceps (Kempt) Ant Venom (Formicidae: Ponerinae). Toxins (Basel), 9(1):5.

Summary/Results: Some toxins obtained from invertebrate venoms have anticonvulsant effects. Crude venom of Dinoponera quadriceps was isolated via chromatography which resulted in six fractions called DqTx1-DqTx6. Each fraction of the venom was injected into lateral ventricle of mice and their behavior was then monitored. When the fractions were given, no behavioral changes were observed. However, when the fractions were injected 20 minutes before injection of BIC, fractions 1, 4, and 6 increased the delay of onset of tonic-clonic seizures(the only fraction that did not do this was fraction 5). Fraction 6 was the most effectful, protecting 62.5 percent of the mice against tonic-clonic seizures. Overall, this study found that ant venoms contain compounds that act as anticonvulsants and that they can be used in future research on this topic.