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Kajevu N, Lipponen A, Andrade P, Bañuelos I, Puhakka N, Hämäläinen E, Natunen T, Hiltunen M, Pitkänen A. Treatment of Status Epilepticus after Traumatic Brain Injury Using an Antiseizure Drug Combined with a Tissue Recovery Enhancer Revealed by Systems Biology. Int J Mol Sci 2023; 24:14049. [PMID: 37762352 PMCID: PMC10531083 DOI: 10.3390/ijms241814049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 08/30/2023] [Accepted: 09/07/2023] [Indexed: 09/29/2023] Open
Abstract
We tested a hypothesis that in silico-discovered compounds targeting traumatic brain injury (TBI)-induced transcriptomics dysregulations will mitigate TBI-induced molecular pathology and augment the effect of co-administered antiseizure treatment, thereby alleviating functional impairment. In silico bioinformatic analysis revealed five compounds substantially affecting TBI-induced transcriptomics regulation, including calpain inhibitor, chlorpromazine, geldanamycin, tranylcypromine, and trichostatin A (TSA). In vitro exposure of neuronal-BV2-microglial co-cultures to compounds revealed that TSA had the best overall neuroprotective, antioxidative, and anti-inflammatory effects. In vivo assessment in a rat TBI model revealed that TSA as a monotherapy (1 mg/kg/d) or in combination with the antiseizure drug levetiracetam (LEV 150 mg/kg/d) mildly mitigated the increase in plasma levels of the neurofilament subunit pNF-H and cortical lesion area. The percentage of rats with seizures during 0-72 h post-injury was reduced in the following order: TBI-vehicle 80%, TBI-TSA (1 mg/kg) 86%, TBI-LEV (54 mg/kg) 50%, TBI-LEV (150 mg/kg) 40% (p < 0.05 vs. TBI-vehicle), and TBI-LEV (150 mg/kg) combined with TSA (1 mg/kg) 30% (p < 0.05). Cumulative seizure duration was reduced in the following order: TBI-vehicle 727 ± 688 s, TBI-TSA 898 ± 937 s, TBI-LEV (54 mg/kg) 358 ± 715 s, TBI-LEV (150 mg/kg) 42 ± 64 (p < 0.05 vs. TBI-vehicle), and TBI-LEV (150 mg/kg) combined with TSA (1 mg/kg) 109 ± 282 s (p < 0.05). This first preclinical intervention study on post-TBI acute seizures shows that a combination therapy with the tissue recovery enhancer TSA and LEV was safe but exhibited no clear benefit over LEV monotherapy on antiseizure efficacy. A longer follow-up is needed to confirm the possible beneficial effects of LEV monotherapy and combination therapy with TSA on chronic post-TBI structural and functional outcomes, including epileptogenesis.
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Affiliation(s)
- Natallie Kajevu
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Anssi Lipponen
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, P.O. Box 95, 70701 Kuopio, Finland
| | - Pedro Andrade
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Ivette Bañuelos
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Noora Puhakka
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Elina Hämäläinen
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Teemu Natunen
- Institute of Biomedicine, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Mikko Hiltunen
- Institute of Biomedicine, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
| | - Asla Pitkänen
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
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Mensah JA, Johnson K, Reilly CA, Wilcox KS, Rower JE, Metcalf CS. Evaluating the efficacy of prototype antiseizure drugs using a preclinical pharmacokinetic approach. Epilepsia 2022; 63:2937-2948. [PMID: 36054499 PMCID: PMC9669179 DOI: 10.1111/epi.17402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/25/2022] [Accepted: 08/25/2022] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Pharmacokinetics (PK) of a drug drive its exposure, efficacy, and tolerability. A thorough preclinical PK assessment of antiseizure medications (ASMs) is therefore essential to evaluate the clinical potential. We tested protection against evoked seizures of prototype ASMs in conjunction with analysis of plasma and brain PK as a proof-of-principle study to enhance our understanding of drug efficacy and duration of action using rodent seizure models. METHODS In vivo seizure protection assays were performed in adult male CF-1 mice and Sprague Dawley rats. Clobazam (CLB), N-desmethyl CLB (NCLB), carbamazepine (CBZ), CBZ-10,11-epoxide (CBZE), sodium valproate (VPA), and levetiracetam (LEV) concentrations were quantified in plasma and brain using liquid chromatography-tandem mass spectrometry. Mean concentrations of each analyte were calculated and used to determine PK parameters via noncompartmental analysis in Phoenix WinNonLin. RESULTS NCLB concentrations were approximately 10-fold greater than CLB in mice. The antiseizure profile of CLB was partially sustained by NCLB in mice. CLB concentrations were lower in rats than in mice. CBZE plasma exposures were approximately 70% of CBZ in both mice and rats, likely contributing to the antiseizure effect of CBZ. VPA showed a relatively short half-life in both mice and rats, which correlated with a sharp decline in efficacy. LEV had a prolonged brain and plasma half-life, associated with a prolonged duration of action in mice. SIGNIFICANCE The study demonstrates the utility of PK analyses for understanding the seizure protection time course in mice and rats. The data indicate that distinct PK profiles of ASMs between mice and rats likely drive differences in drug efficacy between rodent models.
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Affiliation(s)
- Jeffrey A. Mensah
- Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT, USA
| | - Kristina Johnson
- Epilepsy Therapy Screening Program (ETSP) Contract Site, University of Utah, Salt Lake, UT, USA
| | - Christopher A. Reilly
- Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT, USA
- Center for Human Toxicology, College of Pharmacy, University of Utah, Salt Lake City, UT, USA
| | - Karen S. Wilcox
- Epilepsy Therapy Screening Program (ETSP) Contract Site, University of Utah, Salt Lake, UT, USA
- Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT, USA
| | - Joseph E. Rower
- Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT, USA
- Center for Human Toxicology, College of Pharmacy, University of Utah, Salt Lake City, UT, USA
| | - Cameron S. Metcalf
- Epilepsy Therapy Screening Program (ETSP) Contract Site, University of Utah, Salt Lake, UT, USA
- Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT, USA
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Contreras-García IJ, Cárdenas-Rodríguez N, Romo-Mancillas A, Bandala C, Zamudio SR, Gómez-Manzo S, Hernández-Ochoa B, Mendoza-Torreblanca JG, Pichardo-Macías LA. Levetiracetam Mechanisms of Action: From Molecules to Systems. Pharmaceuticals (Basel) 2022; 15:ph15040475. [PMID: 35455472 PMCID: PMC9030752 DOI: 10.3390/ph15040475] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 04/06/2022] [Accepted: 04/06/2022] [Indexed: 11/16/2022] Open
Abstract
Epilepsy is a chronic disease that affects millions of people worldwide. Antiepileptic drugs (AEDs) are used to control seizures. Even though parts of their mechanisms of action are known, there are still components that need to be studied. Therefore, the search for novel drugs, new molecular targets, and a better understanding of the mechanisms of action of existing drugs is still crucial. Levetiracetam (LEV) is an AED that has been shown to be effective in seizure control and is well-tolerable, with a novel mechanism of action through an interaction with the synaptic vesicle protein 2A (SV2A). Moreover, LEV has other molecular targets that involve calcium homeostasis, the GABAergic system, and AMPA receptors among others, that might be integrated into a single mechanism of action that could explain the antiepileptogenic, anti-inflammatory, neuroprotective, and antioxidant properties of LEV. This puts it as a possible multitarget drug with clinical applications other than for epilepsy. According to the above, the objective of this work was to carry out a comprehensive and integrative review of LEV in relation to its clinical uses, structural properties, therapeutical targets, and different molecular, genetic, and systemic action mechanisms in order to consider LEV as a candidate for drug repurposing.
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Affiliation(s)
| | - Noemí Cárdenas-Rodríguez
- Laboratorio de Neurociencias, Subdirección de Medicina Experimental, Instituto Nacional de Pediatría, Ciudad de México 04530, Mexico;
| | - Antonio Romo-Mancillas
- Laboratorio de Diseño Asistido por Computadora y Síntesis de Fármacos, Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, Querétaro 76010, Mexico;
| | - Cindy Bandala
- Neurociencia Básica, Instituto Nacional de Rehabilitación LGII, Secretaría de Salud, Ciudad de México 14389, Mexico;
- Escuela Superior de Medicina, Instituto Politécnico Nacional, Ciudad de México 11340, Mexico
| | - Sergio R. Zamudio
- Departamento de Fisiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México 07738, Mexico;
| | - Saúl Gómez-Manzo
- Laboratorio de Bioquímica Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México 04530, Mexico;
| | - Beatriz Hernández-Ochoa
- Laboratorio de Inmunoquímica, Hospital Infantil de México Federico Gómez, Secretaría de Salud, Ciudad de México 06720, Mexico;
| | - Julieta Griselda Mendoza-Torreblanca
- Laboratorio de Neurociencias, Subdirección de Medicina Experimental, Instituto Nacional de Pediatría, Ciudad de México 04530, Mexico;
- Correspondence: (J.G.M.-T.); (L.A.P.-M.); Tel.: +52-55-1084-0900 (ext. 1441) (J.G.M.-T.)
| | - Luz Adriana Pichardo-Macías
- Departamento de Fisiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México 07738, Mexico;
- Correspondence: (J.G.M.-T.); (L.A.P.-M.); Tel.: +52-55-1084-0900 (ext. 1441) (J.G.M.-T.)
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Relationship between Delta Rhythm, Seizure Occurrence and Allopregnanolone Hippocampal Levels in Epileptic Rats Exposed to the Rebound Effect. Pharmaceuticals (Basel) 2021; 14:ph14020127. [PMID: 33561937 PMCID: PMC7914513 DOI: 10.3390/ph14020127] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 01/29/2021] [Accepted: 02/03/2021] [Indexed: 11/24/2022] Open
Abstract
Abrupt withdrawal from antiepileptic drugs is followed by increased occurrence of epileptic seizures, a phenomenon known as the “rebound effect”. By stopping treatment with levetiracetam (LEV 300 mg/kg/day, n = 15; vs. saline, n = 15), we investigated the rebound effect in adult male Sprague-Dawley rats. LEV was continuously administered using osmotic minipumps, 7 weeks after the intraperitoneal administration of kainic acid (15 mg/kg). The effects of LEV were determined by comparing time intervals, treatments, and interactions between these main factors. Seizures were evaluated by video-electrocorticographic recordings and power band spectrum analysis. Furthermore, we assessed endogenous neurosteroid levels by liquid chromatography-electrospray-tandem mass spectrometry. LEV significantly reduced the percentage of rats experiencing seizures, reduced the seizure duration, and altered cerebral levels of neurosteroids. In the first week of LEV discontinuation, seizures increased abruptly up to 700% (p = 0.002, Tukey’s test). The power of delta band in the seizure postictal component was related to the seizure occurrence after LEV withdrawal (r2 = 0.73, p < 0.001). Notably, allopregnanolone hippocampal levels were positively related to the seizure occurrence (r2 = 0.51, p = 0.02) and to the power of delta band (r2 = 0.67, p = 0.004). These findings suggest a role for the seizure postictal component in the rebound effect, which involves an imbalance of hippocampal neurosteroid levels.
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McCarren HS, Eisen MR, Nguyen DL, Dubée PB, Ardinger CE, Dunn EN, Haines KM, Santoro AN, Bodner PM, Ondeck CA, Honnold CL, McDonough JH, Beske PH, McNutt PM. Characterization and treatment of spontaneous recurrent seizures following nerve agent-induced status epilepticus in mice. Epilepsy Res 2020; 162:106320. [PMID: 32182542 PMCID: PMC7156324 DOI: 10.1016/j.eplepsyres.2020.106320] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 02/21/2020] [Accepted: 03/09/2020] [Indexed: 12/14/2022]
Abstract
PURPOSE To develop and characterize a mouse model of spontaneous recurrent seizures following nerve agent-induced status epilepticus (SE) and test the efficacy of existing antiepileptic drugs. METHODS SE was induced in telemeterized male C57Bl6/J mice by soman exposure, and electroencephalographic activity was recorded for 4-6 weeks. Mice were treated with antiepileptic drugs (levetiracetam, valproic acid, phenobarbital) or corresponding vehicles for 14 d after exposure, followed by 14 d of drug washout. Survival, body weight, seizure characteristics, and histopathology were used to characterize the acute and chronic effects of nerve agent exposure and to evaluate the efficacy of treatments in mitigating or preventing neurological effects. RESULTS Spontaneous recurrent seizures manifested in all survivors, but the number and frequency of seizures varied considerably among mice. In untreated mice, seizures became longer over time. Moderate to severe histopathology was observed in the amygdala, piriform cortex, and CA1. Levetiracetam provided modest improvements in neurological parameters such as reduced spike rate and improved histopathology scores, whereas valproic acid and phenobarbital were largely ineffective. CONCLUSIONS This model of post-SE spontaneous recurrent seizures differs from other experimental models in the brief latency to seizure development, the occurrence of seizures in 100 % of exposed animals, and the lack of damage to CA4/dentate gyrus. It may serve as a useful tool for rapidly and efficiently screening novel therapies that would be effective against severe epilepsy cases.
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Affiliation(s)
- Hilary S McCarren
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States.
| | - Margaret R Eisen
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - Dominique L Nguyen
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - Parker B Dubée
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - Cherish E Ardinger
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - Emily N Dunn
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - Kari M Haines
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - Antonia N Santoro
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - Paige M Bodner
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - Celinia A Ondeck
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - Cary L Honnold
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - John H McDonough
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - Phillip H Beske
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
| | - Patrick M McNutt
- United States Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Rd Aberdeen Proving Ground, MD, 21010, United States
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Canisius TP, Soons JH, Verschuure P, Wammes-van der Heijden EA, Rouhl RP, Majoie HM. Therapeutic drug monitoring of anti-epileptic drugs – a clinical verification of volumetric absorptive micro sampling. ACTA ACUST UNITED AC 2020; 58:828-835. [DOI: 10.1515/cclm-2019-0784] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 12/16/2019] [Indexed: 12/21/2022]
Abstract
AbstractBackgroundTherapeutic drug monitoring (TDM) of antiepileptic drugs (AEDs) can serve as a valuable tool in optimising and individualising epilepsy treatment, especially in vulnerable groups such as pregnant women, the elderly and children. Unfortunately, TDM is often performed suboptimally due to limitations in blood collection. Therefore, we investigated volumetric absorptive micro sampling (VAMS) – a new home-sampling technique. We aimed to evaluate VAMS to determine and quantify the different AEDs and concentrations of 16 different AEDs in whole blood collected by VAMS.MethodsPatient blood samples (n = 138) were collected via venepunctures at the Academic Centre for Epileptology Kempenhaeghe. AED concentrations were determined, and these concentrations were used to compare the VAMS method (whole blood) with the conventional method (serum). In addition, the recovery was examined as well as the impact of haematocrit. Finally, AED-spiked blood was used to test the stability of the AEDs inside the micro-sampler devices over a period of time and whether temperature had an effect on the stability.ResultsVAMS allows for an accurate detection of 16 different AEDs within 2 days after sampling. Deviation in recovery was less than 10% and high correlations were found between VAMS and conventional sampling. Moreover, haematocrit does not have an effect with values between 0.3 and 0.5 (L/L). Finally, although storage temperature of VAMS does affect some AEDs, most are unaffected.ConclusionsVAMS enables an accurate detection of a wide variety of AEDs within 2 days after sampling.
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Affiliation(s)
- Thierry P.I.J.M. Canisius
- Laboratory Clinical Chemistry and Pharmacology, Academic Centre for Epileptology Kempenhaeghe Maastricht UMC+, VE Heeze, the Netherlands
| | - J.W.P. Hans Soons
- Laboratory Clinical Chemistry and Pharmacology, Academic Centre for Epileptology Kempenhaeghe Maastricht UMC+, VE Heeze, the Netherlands
| | - Pauline Verschuure
- Laboratory Clinical Chemistry and Pharmacology, Academic Centre for Epileptology Kempenhaeghe Maastricht UMC+, VE Heeze, the Netherlands
| | - Emmeke A. Wammes-van der Heijden
- Laboratory Clinical Chemistry and Pharmacology, Academic Centre for Epileptology Kempenhaeghe Maastricht UMC+, VE Heeze, the Netherlands
| | - Rob P.W. Rouhl
- Department of Neurology, Academic Centre for Epileptology Kempenhaeghe Maastricht UMC+, Heeze, the Netherlands
- School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, the Netherlands
| | - H.J. Marian Majoie
- Department of Neurology, Academic Centre for Epileptology Kempenhaeghe Maastricht UMC+, Heeze, the Netherlands
- School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, the Netherlands
- School of Health Professions Education, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, the Netherlands
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Sarangi SC, Pattnaik SS, Katyal J, Kaleekal T, Dinda AK. An interaction study of Ocimum sanctum L. and levetiracetam in pentylenetetrazole kindling model of epilepsy. JOURNAL OF ETHNOPHARMACOLOGY 2020; 249:112389. [PMID: 31739106 DOI: 10.1016/j.jep.2019.112389] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 07/24/2019] [Accepted: 11/11/2019] [Indexed: 06/10/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Ocimum sanctum L. commonly known as tulsi (synonym of Ocimum tenuiflorum L.) is widely used in Ayurveda medicine and is having multitude neuromodulatory effect including the anticonvulsant effect in acute seizure models as per previous studies. In India, it is used for the treatment of epilepsy as traditional medicine. However, its role in chronic seizure model and interaction with newer antiepileptic drugs has not been investigated, which will enhance its translational value. AIM OF THE STUDY Current study investigated the effect of Ocimum on chronic seizure model and its interaction with levetiracetam (LEV), a newer antiepileptic drug. MATERIALS AND METHODS The adjuvant role of Ocimum sanctum hydroalcoholic extracts (OSHE) 1000 mg/kg along with LEV 300 mg/kg was studied in adult male Wistar rats with mean weight of 227.84 ± 21.68 g using pentylenetetrazole (30 mg/kg, i.p.) kindling (K) (with maximum 24 injections on alternate days and challenge on 7th-day). Along with seizure score, neurobehavioral, brain tissue oxidative stress and histopathology status were assessed. Pharmacokinetic interaction was assessed between LEV and OSHE after 14 days of drug treatment. RESULTS K-LEV + OSHE had least seizure score during kindling and on the pentylenetetrazole-challenge test (p=0.031) than other kindling groups. Seizure protection was more in K-LEV + OSHE (85.72%) than others (K-LEV-42.86%, K-OSHE-42.86%, and K-Control-28.58%). Ocimum treated groups had better memory retention potential as evident from Morris water maze (MWM), passive avoidance test but not in an elevated plus maze test. Oxidative-stress was lower in Ocimum treated groups than K-Control group. As per histopathology, K-LEV + OSHE group had the least neuronal degeneration among kindling groups. There was no significant pharmacokinetic interaction between LEV and OSHE, except increased Tmax in LEV + OSHE group than LEV alone (p=0.009). CONCLUSIONS Ocimum per se and combination with levetiracetam treatment exerted better seizure control, memory retention, oxidative stress reduction, and neuronal structure preservation than kindling control group. There was a very minimal drug interaction between Ocimum and LEV. So, Ocimum as an adjuvant to LEV may be shelpful in enhancing the antiepileptic effect and also in minimizing the adverse effects.
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Affiliation(s)
| | - Soumya S Pattnaik
- Department of Pharmacology, All India Institute of Medical Sciences, New Delhi, India
| | - Jatinder Katyal
- Department of Pharmacology, All India Institute of Medical Sciences, New Delhi, India
| | - Thomas Kaleekal
- Department of Pharmacology, All India Institute of Medical Sciences, New Delhi, India
| | - A K Dinda
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India
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Nirwan N, Vyas P, Vohora D. Animal models of status epilepticus and temporal lobe epilepsy: a narrative review. Rev Neurosci 2018; 29:757-770. [DOI: 10.1515/revneuro-2017-0086] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 01/26/2018] [Indexed: 11/15/2022]
Abstract
Abstract
Temporal lobe epilepsy (TLE) is the chronic and pharmacoresistant form of epilepsy observed in humans. The current literature is insufficient in explicating the comprehensive mechanisms underlying its pathogenesis and advancement. Consequently, the development of a suitable animal model mimicking the clinical characteristics is required. Further, the relevance of status epilepticus (SE) to animal models is dubious. SE occurs rarely in people; most epilepsy patients never experience it. The present review summarizes the established animal models of SE and TLE, along with a brief discussion of the animal models that have the distinctiveness and carries the possibility to be developed as effective models for TLE. The review not only covers the basic requirements, mechanisms, and methods of induction of each model but also focuses upon their major limitations and possible modifications for their future use. A detailed discussion on chemical, electrical, and hypoxic/ischemic models as well as a brief explanation on the genetic models, most of which are characterized by development of SE followed by neurodegeneration, is presented.
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Affiliation(s)
- Nikita Nirwan
- Neurobehavioral Pharmacology Laboratory , Department of Pharmacology , School of Pharmaceutical Education and Research, Jamia Hamdard , New Delhi 110062 , India
| | - Preeti Vyas
- Neurobehavioral Pharmacology Laboratory , Department of Pharmacology , School of Pharmaceutical Education and Research, Jamia Hamdard , New Delhi 110062 , India
| | - Divya Vohora
- Neurobehavioral Pharmacology Laboratory , Department of Pharmacology , School of Pharmaceutical Education and Research, Jamia Hamdard , New Delhi 110062 , India
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Zhou T, Wang N, Xu L, Huang H, Yu C, Zhou H. Effects of carbamazepine combined with vitamin B12 on levels of plasma homocysteine, hs-CRP and TNF-α in patients with epilepsy. Exp Ther Med 2018; 15:2327-2332. [PMID: 29563977 PMCID: PMC5854944 DOI: 10.3892/etm.2018.5698] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 12/11/2017] [Indexed: 01/24/2023] Open
Abstract
The efficacy of carbamazepine combined with vitamin B12 in epilepsy treatment by comparing levels of plasma homocysteine (Hcy), serum TNF-α and hs-CRP in patients with epilepsy before and after treatment was investigated. Fifty-eight patients with epilepsy who were admitted and received treatment in The First People's Hospital of Xuzhou were recruited as subjects, and fifty-eight healthy volunteers were recruited as the control group. Patients were treated with carbamazepine combined with vitamin B12 for a period of three months. The mRNA and protein levels of TNF-α and hs-CRP in serum were measured before and after treatment using semi-quantitative RT-PCR and western blotting, respectively. The plasma Hcy levels were measured as well. Within one year after the 3-month treatment, the frequency and duration of seizure were tracked. After treatment with carbamazepine combined with vitamin B12 for patients with epilepsy, the Hcy level was significantly higher than that before treatment and that in the control group (P<0.01). The mRNA and protein levels of TNF-α and hs-CRP in serum were significantly higher in patients than that in healthy people (P<0.01). After treatment these levels were reduced (P<0.01), but still higher than those in healthy people (P<0.05, P<0.01). After treatment, the frequency and duration of seizures were all reduced (P<0.05, P<0.01). The results suggested that carbamazepine combined with vitamin B12 was effective in treatment of epilepsy by reducing levels of TNF-α and hs-CRP in the serum, but had a risk of increasing the Hcy level.
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Affiliation(s)
- Tianchi Zhou
- School of Clinical Medicine, Kangda College of Nanjing Medical University, Lianyungang, Jiangsu 222002, P.R. China
| | - Nuan Wang
- Department of Neurology, The First People's Hospital of Xuzhou, Xuzhou, Jiangsu 221000, P.R. China
| | - Lei Xu
- Department of Pharmacy, The First People's Hospital of Xuzhou, Xuzhou, Jiangsu 221000, P.R. China
| | - Hongli Huang
- Department of Neurology, The First People's Hospital of Xuzhou, Xuzhou, Jiangsu 221000, P.R. China
| | - Chunyu Yu
- Department of Neurology, The First People's Hospital of Xuzhou, Xuzhou, Jiangsu 221000, P.R. China
| | - Hao Zhou
- Department of Neurology, The First People's Hospital of Xuzhou, Xuzhou, Jiangsu 221000, P.R. China
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Deseure K, Hans GH. Differential drug effects on spontaneous and evoked pain behavior in a model of trigeminal neuropathic pain. J Pain Res 2017; 10:279-286. [PMID: 28184169 PMCID: PMC5291328 DOI: 10.2147/jpr.s124526] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PURPOSE Baclofen and morphine have shown efficacy against mechanical allodynia after infraorbital nerve chronic constriction injury (IoN-CCI). No drug effects have yet been reported on spontaneous trigeminal neuropathic pain. It has been proposed that the directed face grooming behavior that also develops following IoN-CCI offers a measure of spontaneous trigeminal neuropathic pain. SUBJECTS AND METHODS We examined the effects of a continuous 1-week infusion of 30 mg/day carbamazepine (the first-line drug treatment for trigeminal neuralgia), 1.06 mg/day baclofen, 4.18 mg/day clomipramine, and 5 mg/day morphine on spontaneous and mechanically evoked pain behavior (ie, directed face grooming and von Frey testing) in IoN-CCI rats. RESULTS Isolated face grooming was significantly reduced in rats receiving carbamazepine and baclofen but not in clomipramine- or morphine-treated rats. All drugs showed significant antiallodynic effects; carbamazepine showed the strongest effects, whereas clomipramine had only minor efficacy. CONCLUSION The tested drugs have differential effects in the IoN-CCI model, and different neuropathological mechanisms may underlie the different somatosensory symptoms in this model. A mechanism-based approach may be needed to treat (trigeminal) neuropathic pain. The present data support IoN-CCI as a model of trigeminal neuralgia in which isolated face grooming is used as a measure of spontaneous neuropathic pain.
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Affiliation(s)
- K Deseure
- Department of Medicine, Laboratory for Pain Research, University of Antwerp, Wilrijk
| | - G H Hans
- Multidisciplinary Pain Center, Antwerp University Hospital, Edegem, Belgium
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Jefferys J, Steinhäuser C, Bedner P. Chemically-induced TLE models: Topical application. J Neurosci Methods 2016; 260:53-61. [DOI: 10.1016/j.jneumeth.2015.04.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 04/17/2015] [Accepted: 04/23/2015] [Indexed: 12/26/2022]
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Opportunities for improving animal welfare in rodent models of epilepsy and seizures. J Neurosci Methods 2015; 260:2-25. [PMID: 26376175 DOI: 10.1016/j.jneumeth.2015.09.007] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 09/01/2015] [Accepted: 09/08/2015] [Indexed: 01/31/2023]
Abstract
Animal models of epilepsy and seizures, mostly involving mice and rats, are used to understand the pathophysiology of the different forms of epilepsy and their comorbidities, to identify biomarkers, and to discover new antiepileptic drugs and treatments for comorbidities. Such models represent an important area for application of the 3Rs (replacement, reduction and refinement of animal use). This report provides background information and recommendations aimed at minimising pain, suffering and distress in rodent models of epilepsy and seizures in order to improve animal welfare and optimise the quality of studies in this area. The report includes practical guidance on principles of choosing a model, induction procedures, in vivo recordings, perioperative care, welfare assessment, humane endpoints, social housing, environmental enrichment, reporting of studies and data sharing. In addition, some model-specific welfare considerations are discussed, and data gaps and areas for further research are identified. The guidance is based upon a systematic review of the scientific literature, survey of the international epilepsy research community, consultation with veterinarians and animal care and welfare officers, and the expert opinion and practical experience of the members of a Working Group convened by the United Kingdom's National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs).
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Lévesque M, Behr C, Avoli M. The anti-ictogenic effects of levetiracetam are mirrored by interictal spiking and high-frequency oscillation changes in a model of temporal lobe epilepsy. Seizure 2014; 25:18-25. [PMID: 25645630 DOI: 10.1016/j.seizure.2014.11.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 11/18/2014] [Accepted: 11/20/2014] [Indexed: 12/31/2022] Open
Abstract
PURPOSE Mesial temporal lobe epilepsy (MTLE) is the most prevalent type of partial epileptic disorders. In this study, we have analyzed the impact of levetiracetam (LEV) in the pilocarpine model of MTLE. METHODS Sprague-Dawley rats (n=19) were injected with pilocarpine (380 mg/kg, i.p.) to induce a status epilepticus. Twelve animals were used as controls and seven were treated with LEV. They were implanted with bipolar electrodes in the CA3 subfield of the hippocampus, entorhinal cortex (EC), dentate gyrus (DG) and subiculum and EEG-video monitored continuously from day 4 to day 14 after SE. RESULTS Only 29% of LEV-treated animals had seizures compared to all controls following a latent period that was similar in duration. Seizure rates were lower in LEV-treated animals. In LEV-treated animals without seizures, lower interictal spike rates were found in all regions compared to controls. Analysis of interictal high-frequency oscillations (HFO s) revealed that LEV-treated animals without seizures had lower rates of interictal spikes with ripples (80-200 Hz) in CA3, EC and subiculum (p<0.01), whereas rates of interictal spikes with fast ripples (250-500 Hz) were significantly lower in CA3 and subiculum, compared to controls. CONCLUSION Our findings indicate that the anti-ictogenic properties of LEV are mirrored by decreases of interictal spike rate in temporal lobe regions, and are accompanied by subregion-specific decreases of HFO occurrence in CA3 and subiculum. Overall, this evidence suggest that LEV may inhibit neural network activity in regions that are known to play important roles in MTLE.
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Affiliation(s)
- Maxime Lévesque
- Montreal Neurological Institute and Department of Neurology & Neurosurgery, McGill University, Montréal, Qc H3A 2B4, Canada
| | - Charles Behr
- Montreal Neurological Institute and Department of Neurology & Neurosurgery, McGill University, Montréal, Qc H3A 2B4, Canada
| | - Massimo Avoli
- Montreal Neurological Institute and Department of Neurology & Neurosurgery, McGill University, Montréal, Qc H3A 2B4, Canada.
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Levetiracetam-loaded biodegradable polymer implants in the tetanus toxin model of temporal lobe epilepsy in rats. J Clin Neurosci 2013; 20:148-52. [DOI: 10.1016/j.jocn.2012.05.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 04/25/2012] [Accepted: 05/02/2012] [Indexed: 11/18/2022]
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Levetiracetam suppresses development of spontaneous EEG seizures and aberrant neurogenesis following kainate-induced status epilepticus. Brain Res 2010; 1352:187-99. [PMID: 20599805 DOI: 10.1016/j.brainres.2010.06.061] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Revised: 06/23/2010] [Accepted: 06/23/2010] [Indexed: 01/14/2023]
Abstract
Electroencephalographic (EEG) seizures and behavioral convulsions begin to appear spontaneously a few weeks after chemoconvulsant-induced status epilepticus (SE) and thereafter become more intense. This indicates the progressive development of a long-lasting epileptic focus. In addition, chemoconvulsant-induced SE increases neuronal proliferation in the dentate subgranular zone (SGZ) and ectopic migration of newborn neurons into the dentate hilus of adult animals. These seizure-induced newborn neurons, especially ectopic granule cells in the dentate hilus, are believed to facilitate the development of epileptic foci in animal models of temporal lobe epilepsy. In the present study, we examined the effects of a novel antiepileptic drug, levetiracetam, on the appearance of spontaneous EEG seizures and on the generation of newborn neurons, especially of ectopic granule cells in the dentate hilus, following kainate-induced SE. Levetiracetam treatment for 25 days, initiated 24 hours after induction of kainate-induced SE, significantly decreased the mean duration of spontaneous EEG seizures 58 days later. Levetiracetam treatment also prevented an SE-induced increase in the number of ectopic granule cells observed 58 days after kainate administration by suppressing neuronal proliferation in the dentate SGZ and abnormal migration of newborn neurons from the dentate SGZ to the hilus. These results are in accord with a previous report that an antimitotic agent that reduced the number of newborn neurons significantly decreased the frequency of spontaneous convulsions 1 month after pilocarpine-induced SE. This evidence from the kainate model of temporal lobe epilepsy suggests that levetiracetam may exert antiepileptogenic effects through the suppression of seizure-induced neurogenesis.
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Sardo P, D’Agostino S, Rizzo V, Carletti F, Lonobile G, Ferraro G. In the rat maximal dentate activation model of partial complex epilepsy, the anticonvulsant activity of levetiracetam is modulated by nitric oxide-active drugs. J Neural Transm (Vienna) 2009; 116:831-9. [DOI: 10.1007/s00702-009-0233-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Accepted: 04/21/2009] [Indexed: 11/29/2022]
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Cain SM, Ruest T, Pimlott S, Patterson J, Duncan R, Dewar D, Sills GJ. High resolution micro-SPECT scanning in rats using 125I beta-CIT: effects of chronic treatment with carbamazepine. Epilepsia 2009; 50:1962-70. [PMID: 19453722 DOI: 10.1111/j.1528-1167.2009.02095.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE Carbamazepine (CBZ) is a first-line antiepileptic agent with mood-stabilizing effects in bipolar disorder. It has been reported to influence extracellular concentrations of serotonin and dopamine, suggesting an interaction with monoamine transporters. We have investigated this effect using in vivo single photon emission computed tomography (SPECT) in rats. METHODS Adult male rats received 3 mg/kg/h CBZ via mini-osmotic pump. After 14 days continuous treatment, animals underwent two consecutive SPECT scans, using 125I beta-CIT as a radiotracer to label serotonin transporter (SERT) and dopamine transporter (DAT) sites in the brain. Pharmacologic distinction was enabled by 125I beta-CIT SPECT imaging in rats acutely exposed to the serotonin and dopamine transporter inhibitors, fluoxetine and GBR12909. The interaction between CBZ and 125I beta-CIT binding to SERT and DAT was investigated using in vitro autoradiography. RESULTS Carbamazepine (10 microm) did not affect binding of 125I beta-CIT to isolated rat brain slices, thereby excluding a direct effect on ligand binding to SERT and DAT. SPECT studies with fluoxetine and GBR12909 highlighted SERT binding in thalamus, hippocampus, centromedial nuclei, and occipital cortex, and DAT binding in the caudate. Prolonged treatment with CBZ failed to influence 125I beta-CIT binding to either SERT or DAT in any of the brain regions examined. DISCUSSION This study employed the novel technique of small animal SPECT imaging to investigate the effects of CBZ on monoamine transporters in rat brain. Following prolonged treatment, the drug was without effect on SERT or DAT availability. The mechanism by which CBZ exerts its mood stabilizing effects remains elusive.
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Affiliation(s)
- Stuart M Cain
- Epilepsy Unit, Division of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow, United Kingdom
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Curia G, Longo D, Biagini G, Jones RS, Avoli M. The pilocarpine model of temporal lobe epilepsy. J Neurosci Methods 2008; 172:143-57. [PMID: 18550176 PMCID: PMC2518220 DOI: 10.1016/j.jneumeth.2008.04.019] [Citation(s) in RCA: 729] [Impact Index Per Article: 45.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Revised: 04/17/2008] [Accepted: 04/18/2008] [Indexed: 01/17/2023]
Abstract
Understanding the pathophysiogenesis of temporal lobe epilepsy (TLE) largely rests on the use of models of status epilepticus (SE), as in the case of the pilocarpine model. The main features of TLE are: (i) epileptic foci in the limbic system; (ii) an “initial precipitating injury”; (iii) the so-called “latent period”; and (iv) the presence of hippocampal sclerosis leading to reorganization of neuronal networks. Many of these characteristics can be reproduced in rodents by systemic injection of pilocarpine; in this animal model, SE is followed by a latent period and later by the appearance of spontaneous recurrent seizures (SRSs). These processes are, however, influenced by experimental conditions such as rodent species, strain, gender, age, doses and routes of pilocarpine administration, as well as combinations with other drugs administered before and/or after SE. In the attempt to limit these sources of variability, we evaluated the methodological procedures used by several investigators in the pilocarpine model; in particular, we have focused on the behavioural, electrophysiological and histopathological findings obtained with different protocols. We addressed the various experimental approaches published to date, by comparing mortality rates, onset of SRSs, neuronal damage, and network reorganization. Based on the evidence reviewed here, we propose that the pilocarpine model can be a valuable tool to investigate the mechanisms involved in TLE, and even more so when standardized to reduce mortality at the time of pilocarpine injection, differences in latent period duration, variability in the lesion extent, and SRS frequency.
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Affiliation(s)
- Giulia Curia
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and Physiology, McGill University, Montreal, QC, Canada H3A 2B4
| | - Daniela Longo
- Dipartimento di Scienze Biomediche, Università di Modena e Reggio Emilia, 41100 Modena, Italy
| | - Giuseppe Biagini
- Dipartimento di Scienze Biomediche, Università di Modena e Reggio Emilia, 41100 Modena, Italy
| | - Roland S.G. Jones
- Department of Pharmacy and Pharmacology, University of Bath, Bath BA2 7AY, United Kingdom
| | - Massimo Avoli
- Montreal Neurological Institute and Departments of Neurology & Neurosurgery and Physiology, McGill University, Montreal, QC, Canada H3A 2B4
- Dipartimento di Medicina Sperimentale, Università di Roma “La Sapienza”, 00185 Roma, Italy
- Corresponding author at: 3801 University, Room 794, Montreal, QC, Canada H3A 2B4. Tel.: +1 514 398 1955; fax: +1 514 398 8106.
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Palma E, Ragozzino D, Di Angelantonio S, Mascia A, Maiolino F, Manfredi M, Cantore G, Esposito V, Di Gennaro G, Quarato P, Miledi R, Eusebi F. The Antiepileptic Drug Levetiracetam Stabilizes the Human Epileptic GABAAReceptors upon Repetitive Activation. Epilepsia 2007; 48:1842-9. [PMID: 17521347 DOI: 10.1111/j.1528-1167.2007.01131.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE GABAA receptors from the brain of patients afflicted with mesial temporal lobe epilepsy (MTLE) become less efficient (run-down) when repetitively activated by GABA. Experiments were designed to investigate whether the antiepileptic drug, levetiracetam (LEV), which is used as an adjunctive treatment for medically intractable MTLE, counteracts the GABAA receptor run-down. METHODS GABAA receptors were microtransplanted from the brains of patients afflicted with MTLE into Xenopus oocytes. The GABA-current run-down, caused by repetitive applications of GABA, was investigated using the standard two-microelectrode voltage-clamp technique. Additionally, the GABA-current run-down was investigated directly on pyramidal neurons in human MTLE cortical slices. RESULTS It was found that, in oocytes injected with membranes isolated from the MTLE neocortex, the GABA-current run-down was inhibited by a 3-h pretreatment with 0.5-100 microM LEV. Moreover, the GABAA receptors of pyramidal neurons in human neocortical slices exhibited a current run-down that was significantly reduced by 1 microM LEV. Interestingly, the run-down in oocytes injected with membranes isolated from the MTLE hippocampal subiculum was not affected by LEV. CONCLUSIONS We report that the antiepileptic LEV strengthens GABA inhibition of neuronal circuits by blocking the receptor run-down in the cortex whilst leaving the run-down of GABAA receptors in the hippocampal subiculum unaltered. These findings point to the GABAA receptor run-down as an important event in epileptogenesis and as a possible target for testing and screening antiepileptic drugs.
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Affiliation(s)
- Eleonora Palma
- Dipartimento di Fisiologia Umana e Farmacologia, Universita' di Roma La Sapienza, Roma, Italy.
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De Smedt T, Raedt R, Vonck K, Boon P. Levetiracetam: the profile of a novel anticonvulsant drug-part I: preclinical data. CNS DRUG REVIEWS 2007; 13:43-56. [PMID: 17461889 PMCID: PMC6494143 DOI: 10.1111/j.1527-3458.2007.00004.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The objective of this article was to review and summarize the available reports on the preclinical profile of the novel anticonvulsant drug levetiracetam (LEV). Therefore, a careful search was conducted in the MEDLINE database and combined with guidelines from regulatory agencies, proceedings of professional scientific meetings, and information provided by the manufacturers. This article provides detailed information on the anticonvulsant effects of LEV in various animal models of epilepsy and on its pharmacology in laboratory animals. The mechanism of action of LEV is reviewed, with special regard to its recently discovered binding site, the synaptic vesicle protein 2A. In general, LEV is shown to be a safe, broad-spectrum anticonvulsant drug with highly beneficial pharmacokinetic properties and a distinct mechanism of action. The clinical studies with LEV will be discussed in the second part of this review article to be published subsequently.
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Affiliation(s)
- Tim De Smedt
- Laboratory for Clinical and Experimental Neurophysiology - Reference Center for Refractory Epilepsy, University Hospital Ghent, Ghent, Belgium.
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Gibbs JE, Walker MC, Cock HR. Levetiracetam: antiepileptic properties and protective effects on mitochondrial dysfunction in experimental status epilepticus. Epilepsia 2006; 47:469-78. [PMID: 16529608 DOI: 10.1111/j.1528-1167.2006.00454.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
PURPOSE To assess the anticonvulsant activity of the novel antiepileptic drug, levetiracetam (LEV) in a model of self-sustaining limbic status epilepticus, and to measure the consequence of LEV treatment on the pattern of mitochondrial dysfunction known to occur after status epilepticus (SE). METHODS The rat perforant pathway was stimulated for 2 h to induce self-sustaining status epilepticus (SSSE). Stimulated rats were assigned to one of three treatment groups, receiving intraperitoneal injections of saline, 200 mg/kg LEV, or 1,000 mg/kg LEV, 15 min into SSSE and at 3 times over the next 44-h period. All animals received diazepam after 3-h SSSE to terminate seizures. Forty-four hours later, the hippocampi were extracted and prepared for electrochemical high-performance liquid chromatography (HPLC), to measure reduced glutathione levels, and for spectrophotometric assays to measure activities of mitochondrial enzymes (aconitase, alpha-ketoglutarate dehydrogenase, citrate synthase, complex I, and complex II/III). These parameters were compared between treatment groups and with sham-operated rats. RESULTS LEV administration did not terminate seizures or have any significant effect on spike frequency, although rats that received 1,000 mg/kg LEV did exhibit improved behavioral seizure parameters. Significant biochemical changes occurred in saline-treated stimulated rats compared with shams: with reductions in glutathione, alpha-ketoglutarate dehydrogenase, aconitase, citrate synthase, and complex I activities. Complex II/III activities were unchanged throughout. Rats that received 1,000 mg/kg LEV had significantly improved biochemical parameters, in many instances, comparable to sham control levels. CONCLUSIONS Despite continuing seizures, administration of LEV (1,000 mg/kg) protects against mitochondrial dysfunction, indicating that in addition to its antiepileptic actions, LEV may have neuroprotective effects.
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Affiliation(s)
- Julie E Gibbs
- Centre for Clinical Neurosciences, St George's, University of London, Tooting, London, England
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Ji-qun C, Ishihara K, Nagayama T, Serikawa T, Sasa M. Long-lasting antiepileptic effects of levetiracetam against epileptic seizures in the spontaneously epileptic rat (SER): differentiation of levetiracetam from conventional antiepileptic drugs. Epilepsia 2005; 46:1362-70. [PMID: 16146430 DOI: 10.1111/j.1528-1167.2005.29604.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
PURPOSE Some evidence suggests that levetiracetam (LEV) possesses antiepileptogenic characteristics. The purpose of this study was to investigate the time course of seizure protection by LEV compared with that of phenytoin (PHT), phenobarbital (PB), valproate (VPA), and carbamazepine (CBZ) in the spontaneously epileptic rat (SER). The SER is a double mutant (tm/tm, zi/zi) showing both tonic convulsions and absence-like seizures. METHODS The effect of single (40, 80, and 160 mg/kg, i.p.) and 5-day (80 mg/kg/day, i.p.) administration of LEV on tonic convulsions and absence-like seizures in SERs were studied. Tonic convulsions induced by blowing air onto the animal's head at 5-min intervals for 30 min and spontaneous absence-like seizures characterized by 5- to 7-Hz spike-wave-like complexes in the cortical and hippocampal EEG were recorded for 30 min. In the single-administration study, observations for seizure activity were performed once before and 3 times (45, 75, and 135 min) after drug administration. In the 5-day administration study, seizure observation was performed 4 times for 30 min (once before and 3 times after drug administration) during the 5-day drug-administration period, and continued once a day until 8 days after the final administration. The antiepileptic effects of 5-day administration of conventional AEDs (PHT, PB, VPA, and CBZ) were examined by using similar methods. RESULTS Tonic convulsions and absence-like seizures were inhibited by a single administration of LEV at 80 and 160 mg/kg, i.p., but not significantly at 40 mg/kg, i.p. When LEV was repeatedly administered at 80 mg/kg/day, i.p., for 5 days to SERs, the inhibitory effects on seizures increased with administration time. The number of tonic convulsions and absence-like seizures were significantly reduced to 39.1% and 38.4% compared with previous values, respectively, after 5-day LEV administration. Furthermore, significant inhibition of tonic convulsions was detected <or=3 days after the final administration, and significant inhibition of absence-like seizures was still observed 8 days after the final injection of LEV. This demonstrates long-lasting seizure protection by LEV after cessation of treatment. PHT, PB, VPA, and CBZ inhibited tonic convulsions more potently compared with LEV in SERs. The maximal antiseizure effects of these drugs were reached after the initial administration, with almost the same antiseizure effects observed through day 5, despite continued drug administration. Moreover, a long-lasting treatment effect was not observed with any of these drugs except for PHT and CBZ, both of which showed moderately prolonged antiseizure effects. CONCLUSIONS These results show that LEV is effective in the treatment of both convulsive and absence-like seizures in SERs after single- and multiple-dose administration. Interestingly, in the 5-day administration study, it was found that the antiepileptic effects for tonic convulsions and absence-like seizures were observed both during the drug-administration period and <or=8 days after the final administration of LEV. This long-lasting effect suggests that LEV may possess an antiepileptogenic effect that it does not share with PHT, PB, VPA, and CBZ.
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Affiliation(s)
- Cai Ji-qun
- Department of Pharmacology, Hiroshima University School of Medicine, Hiroshima, Japan
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Oliveira AA, Nogueira CRA, Nascimento VS, Aguiar LMV, Freitas RM, Sousa FCF, Viana GSB, Fonteles MMF. Evaluation of levetiracetam effects on pilocarpine-induced seizures: Cholinergic muscarinic system involvement. Neurosci Lett 2005; 385:184-8. [PMID: 15967574 DOI: 10.1016/j.neulet.2005.05.048] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2004] [Revised: 03/05/2005] [Accepted: 05/24/2005] [Indexed: 10/25/2022]
Abstract
Levetiracetam (LEV) is a new antiepileptic drug effective as adjunctive therapy for partial seizures. It displays a unique pharmacological profile against experimental models of seizures, including pilocarpine-induced seizures in rodents. Aiming to clarify if anticonvulsant activity of LEV occurs due to cholinergic alterations, adult male mice received LEV injections before cholinergic agonists' administration. Pretreatment with LEV (30-200 mg/kg, i.p.) increased the latencies of seizures, but decreased status epilepticus and death on the seizure model induced by pilocarpine, 400 mg/kg, s.c. (P400). LEV (LEV200, 200 mg/kg, i.p.) pretreatment also reduced the intensity of tremors induced by oxotremorine (0.5 mg/kg, i.p). [3H]-N-methylscopolamine-binding assays in mice hippocampus showed that LEV200 pretreatment reverts the downregulation on muscarinic acetylcholine receptors (mAChR), induced by P400 administration, bringing back these density values to control ones (0.9% NaCl, i.p.). However, subtype-specific-binding assays revealed that P400- and LEV-alone treatments result in M1 and M2 subtypes decrease, respectively. The agonist-like behavior of LEV on the inhibitory M2 mAChR subtype, observed in this work, could contribute to explain the reduction on oxotremorine-induced tremors and the delay on pilocarpine-induced seizures, by an increase in the attenuation of neuronal activity mediated by the M1 receptors.
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Affiliation(s)
- A A Oliveira
- Department of Physiology and Pharmacology, Laboratory of Neuropharmacology, School of Medicine, Federal University of Ceará, Rua Padre Frota, 189, Monte Castelo, Fortaleza, CEP 60325-160, Ceará, Brazil.
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Mazarati AM, Baldwin R, Klitgaard H, Matagne A, Wasterlain CG. Anticonvulsant effects of levetiracetam and levetiracetam-diazepam combinations in experimental status epilepticus. Epilepsy Res 2004; 58:167-74. [PMID: 15120747 DOI: 10.1016/j.eplepsyres.2004.02.002] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2003] [Revised: 01/09/2004] [Accepted: 02/13/2004] [Indexed: 11/28/2022]
Abstract
Status epilepticus (SE) is a neurological emergency, with high mortality and high morbidity among survivors, and novel therapeutic agents are needed to improve this picture. We examined the effects of the antiepileptic drug levetiracetam (LEV) in an experimental model of self-sustaining status epilepticus (SSSE), induced in rats by electrical stimulation of the perforant path. LEV's unique spectrum of anticonvulsant activity, very high therapeutic index, and neuroprotective properties, make it a potentially interesting agent in the treatment of SE. Pretreatment with LEV intravenously reduced (30 mg/kg) or prevented (50-1000 mg/kg) the development of self-sustaining seizures. Treatment during the maintenance phase of SSSE diminished (at 200 mg/kg) or aborted seizures (in doses of 500 or 1000 mg/kg). Addition of LEV significantly enhanced the anticonvulsant effects of diazepam (DZP), even when both drugs where given in doses far below their therapeutic level. We conclude that LEV deserves further evaluation in the treatment of status epilepticus.
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Affiliation(s)
- Andrey M Mazarati
- Department of Neurology, Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
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Zhang ZJ, Xing GQ, Russell S, Obeng K, Post RM. Unidirectional Cross-tolerance from Levetiracetam to Carbamazepine in Amygdala-kindled Seizures. Epilepsia 2003; 44:1487-93. [PMID: 14636317 DOI: 10.1111/j.0013-9580.2003.34803.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE Tolerance is a potential problem in long-term anticonvulsant therapy of epilepsy, bipolar disorder, and neuropathic pain. The present study was designed to determine whether cross-tolerance occurs between levetiracetam (LEV) and carbamazepine (CBZ) in amygdala-kindled rats. METHODS Male Sprague-Dawley rats were implanted with an electrode into the left amygdala. While kindling stimulation was started, animals received repeated treatment (i.p.) with saline (n = 7) or LEV (150 mg/kg, n = 8). Saline-injected rats were subsequently challenged with a single dose of 150 mg/kg LEV when full kindling developed (stage > or =4). Both groups of rats were then administered long-term CBZ (5 mg/kg) until rats developed complete tolerance. All CBZ-tolerant rats were subsequently re-exposed to LEV (150 mg/kg) for an additional 10 consecutive days. RESULTS Repeated LEV treatment significantly suppressed the increase in seizure stage, seizure duration, and afterdischarge duration induced by amygdala stimulation, markedly increasing the number of stimulations to achieve a kindling major motor seizure. The LEV challenge produced a more robust suppression of seizure stage in saline-injected rats compared with LEV-treated animals. CBZ treatment markedly suppressed fully kindled seizures in rats initially injected with saline, and then anticonvulsant tolerance rapidly developed after 3-4 days of repeated treatment. In contrast, rats that had initially received repeated LEV treatment did not show a response to treatment with CBZ (5 mg/kg). When CBZ-tolerant rats were subsequently exposed to LEV (150 mg/kg), noticeable anticonvulsant effects were observed; but these were gradually lost with increasing numbers of LEV exposures. CONCLUSIONS Whereas LEV shows potent antiepileptogenic and anticonvulsant effects in amygdala-kindled rats, its repeated treatment induces anticonvulsant tolerance and unidirectional cross-tolerance to CBZ. In contrast, anticonvulsant tolerance to CBZ does not transfer to LEV. The mechanistic implications of the present results for clinical therapeutics remain to be evaluated.
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Affiliation(s)
- Zhang-Jin Zhang
- Department of Psychiatry, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, U.S.A.
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