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Lazar S, Neufeld-Cohen A, Egoz I, Baranes S, Gez R, Glick P, Cohen M, Gutman H, Chapman S, Gore A. Efficacy of a combined anti-seizure treatment against cholinergic established status epilepticus following a sarin nerve agent insult in rats. Toxicol Appl Pharmacol 2024; 484:116870. [PMID: 38395364 DOI: 10.1016/j.taap.2024.116870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 02/11/2024] [Accepted: 02/19/2024] [Indexed: 02/25/2024]
Abstract
The development of refractory status epilepticus (SE) following sarin intoxication presents a therapeutic challenge. Here, we evaluated the efficacy of delayed combined double or triple treatment in reducing abnormal epileptiform seizure activity (ESA) and the ensuing long-term neuronal insult. SE was induced in rats by exposure to 1.2 LD50 sarin followed by treatment with atropine and TMB4 (TA) 1 min later. Double treatment with ketamine and midazolam or triple treatment with ketamine, midazolam and levetiracetam was administered 30 min post-exposure, and the results were compared to those of single treatment with midazolam alone or triple treatment with ketamine, midazolam, and valproate, which was previously shown to ameliorate this neurological insult. Toxicity and electrocorticogram activity were monitored during the first week, and behavioral evaluations were performed 2 weeks post-exposure, followed by biochemical and immunohistopathological analyses. Both double and triple treatment reduced mortality and enhanced weight recovery compared to TA-only treatment. Triple treatment and, to a lesser extent, double treatment significantly ameliorated the ESA duration. Compared to the TA-only or the TA+ midazolam treatment, both double and triple treatment reduced the sarin-induced increase in the neuroinflammatory marker PGE2 and the brain damage marker TSPO and decreased gliosis, astrocytosis and neuronal damage. Finally, both double and triple treatment prevented a change in behavior, as measured in the open field test. No significant difference was observed between the efficacies of the two triple treatments, and both triple combinations completely prevented brain injury (no differences from the naïve rats). Delayed double and, to a greater extent, triple treatment may serve as an efficacious delayed therapy, preventing brain insult propagation following sarin-induced refractory SE.
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Affiliation(s)
- Shlomi Lazar
- Department of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel.
| | - Adi Neufeld-Cohen
- Department of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Inbal Egoz
- Department of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Shlomi Baranes
- Department of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Rellie Gez
- Department of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Pnina Glick
- Department of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Maayan Cohen
- Department of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Hila Gutman
- Department of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Shira Chapman
- Department of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Ariel Gore
- Department of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel.
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Penatzer JA, Prince N, Miller JV, Newman M, Lynch C, Hobbs GR, Boyd JW. Corticosterone and chlorpyrifos oxon exposure elicits spatiotemporal MAPK phosphoprotein signaling in a mouse brain. Food Chem Toxicol 2021; 155:112421. [PMID: 34280473 DOI: 10.1016/j.fct.2021.112421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/12/2021] [Accepted: 07/14/2021] [Indexed: 12/26/2022]
Abstract
Chlorpyrifos (CPF) is one of the most widely-used pesticides globally for agricultural purposes. Certain occupations (e.g., farmers, military) are at an increased risk for high-dose exposure to CPF, which can lead to seizures and irreversible brain injury. Workers with the highest risk of exposure typically experience increased circulating cortisol levels, which is related to physiological stress. To better represent this exposure scenario, a mouse model utilized exogenous administration of corticosterone (CORT; high physiologic stress mimic) in combination with chlorpyrifos oxon (CPO; oxon metabolite of CPF); this combination increases neuroinflammation post-exposure. In the present study adult male C57BL/6J mice were given CORT (200 μg/mL) in drinking water for seven days followed by a single intraperitoneal injection of CPO (8.0 mg/kg) on day eight, and euthanized 0.5, 2, and 24 h post-injection. Ten post-translationally modified proteins were measured in the frontal cortex and striatum to evaluate brain region-specific effects. The spatiotemporal response to CORT + CPO sequentially activated phosphoproteins (p-ERK1/2, p-MEK1/2, p-JNK) involved in mitogen-activated protein kinase (MAPK) signaling. Observed p-ZAP70 responses further integrated MAPK signaling and provided a spatiotemporal connection between protein phosphorylation and neuroinflammation. This study provides insight into the spatiotemporal cellular signaling cascade following CORT + CPO exposure that represent these vulnerable populations.
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Affiliation(s)
- Julia A Penatzer
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | - Nicole Prince
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | | | - Mackenzie Newman
- Department of Orthopaedics, West Virginia University School of Medicine, Morgantown, WV, USA
| | - Cayla Lynch
- Department of Orthopaedics, West Virginia University School of Medicine, Morgantown, WV, USA; Cellular and Integrative Physiology Department, West Virginia University School of Medicine, Morgantown, WV, USA
| | - Gerald R Hobbs
- Department of Statistics, West Virginia University, Morgantown, WV, USA
| | - Jonathan W Boyd
- Department of Orthopaedics, West Virginia University School of Medicine, Morgantown, WV, USA.
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3
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Gore A, Neufeld-Cohen A, Egoz I, Baranes S, Gez R, Efrati R, David T, Dekel Jaoui H, Yampolsky M, Grauer E, Chapman S, Lazar S. Neuroprotection by delayed triple therapy following sarin nerve agent insult in the rat. Toxicol Appl Pharmacol 2021; 419:115519. [PMID: 33823148 DOI: 10.1016/j.taap.2021.115519] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/25/2021] [Accepted: 04/01/2021] [Indexed: 02/08/2023]
Abstract
The development of refractory status epilepticus (SE) induced by sarin intoxication presents a therapeutic challenge. In our current research we evaluate the efficacy of a delayed combined triple treatment in ending the abnormal epileptiform seizure activity (ESA) and the ensuing of long-term neuronal insult. SE was induced in male Sprague-Dawley rats by exposure to 1.2LD50 sarin insufficiently treated by atropine and TMB4 (TA) 1 min later. Triple treatment of ketamine, midazolam and valproic acid was administered 30 min or 1 h post exposure and was compared to a delayed single treatment with midazolam alone. Toxicity and electrocorticogram activity were monitored during the first week and behavioral evaluation performed 3 weeks post exposure followed by brain biochemical and immunohistopathological analyses. The addition of both single and triple treatments reduced mortality and enhanced weight recovery compared to the TA-only treated group. The triple treatment also significantly minimized the duration of the ESA, reduced the sarin-induced increase in the neuroinflammatory marker PGE2, the brain damage marker TSPO, decreased the gliosis, astrocytosis and neuronal damage compared to the TA+ midazolam or only TA treated groups. Finally, the triple treatment eliminated the sarin exposed increased open field activity, as well as impairing recognition memory as seen in the other experimental groups. The delayed triple treatment may serve as an efficient therapy, which prevents brain insult propagation following sarin-induced refractory SE, even if treatment is postponed for up to 1 h.
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Affiliation(s)
- Ariel Gore
- Department of Pharmacology, Israel Institute for Biological, Chemical and Environmental Sciences, Ness-Ziona 74100, Israel.
| | - Adi Neufeld-Cohen
- Department of Pharmacology, Israel Institute for Biological, Chemical and Environmental Sciences, Ness-Ziona 74100, Israel
| | - Inbal Egoz
- Department of Pharmacology, Israel Institute for Biological, Chemical and Environmental Sciences, Ness-Ziona 74100, Israel
| | - Shlomi Baranes
- Department of Pharmacology, Israel Institute for Biological, Chemical and Environmental Sciences, Ness-Ziona 74100, Israel
| | - Rellie Gez
- Department of Pharmacology, Israel Institute for Biological, Chemical and Environmental Sciences, Ness-Ziona 74100, Israel
| | - Rahav Efrati
- Department of Pharmacology, Israel Institute for Biological, Chemical and Environmental Sciences, Ness-Ziona 74100, Israel
| | - Tse'ela David
- The Veterinary Center for Pre-clinical Research, Israel Institute for Biological, Chemical and Environmental Sciences, Ness- Ziona 74100, Israel
| | - Hani Dekel Jaoui
- The Veterinary Center for Pre-clinical Research, Israel Institute for Biological, Chemical and Environmental Sciences, Ness- Ziona 74100, Israel
| | - Michael Yampolsky
- The Veterinary Center for Pre-clinical Research, Israel Institute for Biological, Chemical and Environmental Sciences, Ness- Ziona 74100, Israel
| | - Ettie Grauer
- Department of Pharmacology, Israel Institute for Biological, Chemical and Environmental Sciences, Ness-Ziona 74100, Israel
| | - Shira Chapman
- Department of Pharmacology, Israel Institute for Biological, Chemical and Environmental Sciences, Ness-Ziona 74100, Israel
| | - Shlomi Lazar
- Department of Pharmacology, Israel Institute for Biological, Chemical and Environmental Sciences, Ness-Ziona 74100, Israel.
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4
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Andrew PM, Lein PJ. Neuroinflammation as a Therapeutic Target for Mitigating the Long-Term Consequences of Acute Organophosphate Intoxication. Front Pharmacol 2021; 12:674325. [PMID: 34054549 PMCID: PMC8153682 DOI: 10.3389/fphar.2021.674325] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 04/30/2021] [Indexed: 12/14/2022] Open
Abstract
Acute intoxication with organophosphates (OPs) can cause a potentially fatal cholinergic crisis characterized by peripheral parasympathomimetic symptoms and seizures that rapidly progress to status epilepticus (SE). While current therapeutic countermeasures for acute OP intoxication significantly improve the chances of survival when administered promptly, they are insufficient for protecting individuals from chronic neurologic outcomes such as cognitive deficits, affective disorders, and acquired epilepsy. Neuroinflammation is posited to contribute to the pathogenesis of these long-term neurologic sequelae. In this review, we summarize what is currently known regarding the progression of neuroinflammatory responses after acute OP intoxication, drawing parallels to other models of SE. We also discuss studies in which neuroinflammation was targeted following OP-induced SE, and explain possible reasons why such therapeutic interventions have inconsistently and only partially improved long-term outcomes. Finally, we suggest future directions for the development of therapeutic strategies that target neuroinflammation to mitigate the neurologic sequelae of acute OP intoxication.
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Affiliation(s)
| | - Pamela J. Lein
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, United States
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Shi M, Deng S, Cui Y, Chen X, Shi T, Song L, Zhang R, Zhang Y, Xu J, Shi J, Wang C, Li L. Repeated low-dose exposures to sarin disrupted the homeostasis of phospholipid and sphingolipid metabolism in guinea pig hippocampus. Toxicol Lett 2020; 338:32-39. [PMID: 33253782 DOI: 10.1016/j.toxlet.2020.11.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/16/2020] [Accepted: 11/24/2020] [Indexed: 01/22/2023]
Abstract
Repeated low-level exposure to sarin results to hippocampus dysfunction. Metabonomics involves a holistic analysis of a set of metabolites in an organism in the search for a relationship between these metabolites and physiological or pathological changes. The objective of the present study was to evaluate the effects of repeated exposure to low-level sarin on the metabonomics in hippocampus of a guinea pig model. Guinea pigs were divided randomly into control and sarin treated groups (n = 14). Guinea pigs in the control group received saline; while the sarin-treated group received 0.4×LD50 (16.8 μg/kg) sarin. Daily injections (a total of 14 days) were administered sc between the shoulder blades in a volume of 1.0 ml/kg body weight. At the end of the final injection, 6 animals in each group were chosen for Morris water maze test. The rest guinea pigs (n = 8 for each group) were sacrificed by decapitation, and hippocampus were dissected for analysis. Compared with the control-group, the escape latency in sarin-group was significantly (p < 0.05) longer while the crossing times were significantly decreased in the Morris water task (p < 0.05). Sarin inhibited activities of acetylcholinesterase (AChE) and neuropathy target esterase (NTE) in hippocampus. The AChE activity of hippocampus from sarin-treated groups is equivalent to 59.9 ± 6.4 %, and the NTE activity of hippocampus from sarin-groups is equivalent to 78.1 ± 8.3 % of that from control-group. Metabolites were identified and validated. A total of 14 variables were selected as potential biomarkers. Phospholipids [phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidic acid (PA), phosphatidylglycerol (PG), phosphatidylinositol (PI), Lysophosphatidylethanolamine (LysoPE or LPE)] and sphingolipids (SPs) [sphinganine (SA), phytosphingosine (PSO) and sphinganine-1-phosphate (SA1P)] were clearly modified. In conclusion, repeated low-dose exposures to sarin disrupted the homeostasis of phospholipid and sphingolipid metabolism in guinea pig hippocampus and may lead to a neuronal-specific function disorders. Identified metabolites such as SA1P need to be studied more deeply on their biological function that against sarin lesions. In future research, we should pay more attention to characterize the physiological roles of lipid metabolism enzymes as well as their involvement in pathologies induced by repeated low-level sarin exposure.
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Affiliation(s)
- Meng Shi
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China
| | - Shikun Deng
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China
| | - Yalan Cui
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China
| | - Xuejun Chen
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China
| | - Tong Shi
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China
| | - Liangcai Song
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China
| | - Ruihua Zhang
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China
| | - Yi Zhang
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China
| | - Jianfu Xu
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China
| | - Jingjing Shi
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China
| | - Chen Wang
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China.
| | - Liqin Li
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, PR China.
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Vagima Y, Gur D, Erez N, Achdout H, Aftalion M, Levy Y, Zauberman A, Tidhar A, Gutman H, Lazar S, Israely T, Paran N, Melamed S, Brosh-Nissimov T, Chitlaru T, Sagi I, Mamroud E. Influenza virus infection augments susceptibility to respiratory Yersinia pestis exposure and impacts the efficacy of antiplague antibiotic treatments. Sci Rep 2020; 10:19116. [PMID: 33154422 PMCID: PMC7645720 DOI: 10.1038/s41598-020-75840-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 10/21/2020] [Indexed: 12/29/2022] Open
Abstract
Various respiratory viral infections in general and seasonal influenza in particular may increase the susceptibility to bacterial infections. Plague caused by Yersinia pestis endangers large populations during outbreaks or bioterrorism attacks. Recommended antibiotic countermeasures include well-established protocols based on animal studies and corroborated by effective treatment of human cases. Until now, prior exposure to viral respiratory infections was not taken into consideration when selecting the appropriate treatment for plague. Here, we show that as late as 25 days after exposure to influenza virus, convalescent mice still exhibited an increased susceptibility to sublethal doses of Y. pestis, presented with aberrant cytokine expression, and impaired neutrophil infiltration in the lungs. Increased levels of M2 alveolar macrophages and type II epithelial cells, as well as induction in metalloproteases expression and collagen and laminin degradation, suggested that the previous viral infection was under resolution, correlating with enhanced susceptibility to plague. Surprisingly, postexposure prophylaxis treatment with the recommended drugs revealed that ciprofloxacin was superior to doxycycline in mice recovering from influenza infection. These results suggest that after an influenza infection, the consequences, such as impaired immunity and lung tissue remodeling and damage, should be considered when treating subsequent Y. pestis exposure.
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Affiliation(s)
- Yaron Vagima
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel.
| | - David Gur
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Noam Erez
- Department of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Hagit Achdout
- Department of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Moshe Aftalion
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Yinon Levy
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Ayelet Zauberman
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Avital Tidhar
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Hila Gutman
- Department of Pharmacology, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Shlomi Lazar
- Department of Pharmacology, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Tomer Israely
- Department of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Nir Paran
- Department of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Sharon Melamed
- Department of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Tal Brosh-Nissimov
- Infectious Diseases Unit, Assuta Ashdod University Hospital, Ashdod, Israel
| | - Theodor Chitlaru
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Irit Sagi
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot, Israel
| | - Emanuelle Mamroud
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel.
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7
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Jett D, Sibrizzi C, Blain RB, Hartman P, Lein P, Taylor K, Rooney A. A national toxicology program systematic review of the evidence for long-term effects after acute exposure to sarin nerve agent. Crit Rev Toxicol 2020; 50:474-490. [PMID: 32755358 PMCID: PMC8011809 DOI: 10.1080/10408444.2020.1787330] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 06/22/2020] [Accepted: 06/22/2020] [Indexed: 12/11/2022]
Abstract
Sarin is a highly toxic nerve agent that was developed for chemical warfare during World War II and is used in present conflicts. Immediate effects of acute sarin exposure are established; however, whether effects persist after initial signs have subsided is debated. The National Toxicology Program (NTP) conducted a systematic review to evaluate the evidence for long-term neurological effects following acute (<24 hour) exposure to sarin. The literature search and screening process identified 32 data sets within the 34 human studies and 47 data sets within the 51 animal studies (from 6837 potentially relevant references) that met the objective and the inclusion criteria. Four main health effect categories of neurological response were identified as having sufficient data to reach hazard conclusions: (1) cholinesterase levels; (2) visual and ocular effects; (3) effects on learning, memory, and intelligence; and (4) morphology and histopathology in nervous system tissues. NTP concluded that acute sarin exposure is known to be a neurological hazard to humans in the period following exposure up to 7 days and suspected to be a hazard week to years after exposure, given a lower level of evidence in later time periods. Effects included reduced cholinesterase, visual and ocular effects, impaired learning and memory, and altered nervous system morphology. Further mechanistic, targeted animal studies, translational research, and rapid research responses after human exposures may reduce uncertainties on long-term consequences of sarin.
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Affiliation(s)
- D.A. Jett
- National Institute of Neurological Disorders and Stroke, National Institutes of Health
| | | | | | | | - P.J. Lein
- University of California, Davis, School of Veterinary Medicine, Davis, CA, USA
| | - K.W. Taylor
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, RTP, NC, USA
| | - A.A. Rooney
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, RTP, NC, USA
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8
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Farkhondeh T, Mehrpour O, Buhrmann C, Pourbagher-Shahri AM, Shakibaei M, Samarghandian S. Organophosphorus Compounds and MAPK Signaling Pathways. Int J Mol Sci 2020; 21:ijms21124258. [PMID: 32549389 PMCID: PMC7352539 DOI: 10.3390/ijms21124258] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/07/2020] [Accepted: 06/09/2020] [Indexed: 02/06/2023] Open
Abstract
The molecular signaling pathways that lead to cell survival/death after exposure to organophosphate compounds (OPCs) are not yet fully understood. Mitogen-activated protein kinases (MAPKs) including the extracellular signal-regulated protein kinase (ERK), the c-Jun NH2-terminal kinase (JNK), and the p38-MAPK play the leading roles in the transmission of extracellular signals into the cell nucleus, leading to cell differentiation, cell growth, and apoptosis. Moreover, exposure to OPCs induces ERK, JNK, and p38-MAPK activation, which leads to oxidative stress and apoptosis in various tissues. However, the activation of MAPK signaling pathways may differ depending on the type of OPCs and the type of cell exposed. Finally, different cell responses can be induced by different types of MAPK signaling pathways after exposure to OPCs.
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Affiliation(s)
- Tahereh Farkhondeh
- Medical Toxicology and Drug Abuse Research Center (MTDRC), Birjand University of Medical Sciences (BUMS), Birjand 9717853577, Iran; (T.F.); (O.M.); (A.M.P.-S.)
| | - Omid Mehrpour
- Medical Toxicology and Drug Abuse Research Center (MTDRC), Birjand University of Medical Sciences (BUMS), Birjand 9717853577, Iran; (T.F.); (O.M.); (A.M.P.-S.)
- Rocky Mountain Poison and Drug Safety, Denver Health, Denver, CO 80204, USA
| | - Constanze Buhrmann
- Musculoskeletal Research Group and Tumour Biology, Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig-Maximilian-University Munich, Pettenkoferstrasse 11, D-80336 Munich, Germany;
| | - Ali Mohammad Pourbagher-Shahri
- Medical Toxicology and Drug Abuse Research Center (MTDRC), Birjand University of Medical Sciences (BUMS), Birjand 9717853577, Iran; (T.F.); (O.M.); (A.M.P.-S.)
| | - Mehdi Shakibaei
- Musculoskeletal Research Group and Tumour Biology, Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig-Maximilian-University Munich, Pettenkoferstrasse 11, D-80336 Munich, Germany;
- Correspondence: (M.S.); (S.S.)
| | - Saeed Samarghandian
- Healthy Ageing Research Center, Neyshabur University of Medical Sciences, Neyshabur 9318614139, Iran
- Correspondence: (M.S.); (S.S.)
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9
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Zare Z, Zarbakhsh S, Tehrani M, Mohammadi M. Paraoxon-induced damage in rat hippocampus is associated with alterations in the expression of apoptosis-related proteins. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2020; 166:104580. [PMID: 32448426 DOI: 10.1016/j.pestbp.2020.104580] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 03/02/2020] [Accepted: 04/06/2020] [Indexed: 06/11/2023]
Abstract
To determine the possible role of apoptosis in the development of paraoxon-induced brain damage, we evaluated expression of apoptosis-related proteins, the extent of neuronal damage, and activation of astrocytes in rat hippocampus. Adult male Wistar rats were intraperitoneally injected with one of three doses of paraoxon (0.3, 0.7, or 1 mg/kg) or corn oil (vehicle). After 14 or 28 days, expression of apoptosis-related proteins, including B-cell leukemia/lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax), and caspase-3, as well as the number of neurons and glial fibrillary acidic protein (GFAP) positive cells in hippocampus were examined by western blot, cresyl blue staining, and immunohistochemistry, respectively. After 14 and 28 days, Bax and caspase-3 proteins were significantly increased in rats receiving 0.7 and 1 mg/kg of paraoxon. A significant decrease in Bcl-2 protein levels was also observed in 0.7 and 1 mg/kg groups after 14 days and in 1 mg/kg group after 28 days. Animals treated with 1 mg/kg of paraoxon showed a significant decrease in the number of neurons in the CA1 area. Also, those treated with 0.7 and 1 mg/kg of paraoxon showed an increase in the number of GFAP positive cells in both CA1 and CA3 areas as well as a significant decrease in survived neurons in the CA3 area. Our results indicated that neuronal damage induced by convulsive doses of paraoxon in rat hippocampus is mediated in part through apoptosis mechanism. Activation of astrocytes might lead to reduced extent of damage and damage and consequently increased neuronal survival.
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Affiliation(s)
- Zohreh Zare
- Department of Anatomical Sciences, Molecular and Cell Biology Research Center, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Sam Zarbakhsh
- Nervous System Stem Cells Research Center, Semnan University of Medical Sciences, Semnan, Iran
| | - Mohsen Tehrani
- Department of Immunology, Gastrointestinal Cancer Research Center, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Moslem Mohammadi
- Department of Physiology, Molecular and Cell Biology Research Center, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
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10
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Gore A, Neufeld-Cohen A, Egoz I, Baranes S, Gez R, Grauer E, Chapman S, Lazar S. Efficacy of retigabine in ameliorating the brain insult following sarin exposure in the rat. Toxicol Appl Pharmacol 2020; 395:114963. [PMID: 32209366 DOI: 10.1016/j.taap.2020.114963] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 03/17/2020] [Accepted: 03/20/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Sarin is an irreversible organophosphate cholinesterase inhibitor. Following toxic signs, an extensive long-term brain damage is often reported. Thus, we evaluated the efficacy of a novel anticonvulsant drug retigabine, a modulator of neuronal voltage gated K+ channels, as a neuroprotective agent following sarin exposure. METHODS Rats were exposed to 1 LD50 or 1.2 LD50 sarin and treated at onset of convulsions with retigabine (5 mg/kg, i.p.) alone or in combination with 5 mg/kg atropine and 7.5 mg/kg TMB-4 (TA) respectively. Brain biochemical and immunohistopathological analyses were processed 24 h and 1 week following 1 LD50 sarin exposure and at 4 weeks following exposure to 1.2 LD50 sarin. EEG activity in freely moving rats was also monitored by telemetry during the first week following exposure to 1.2 LD50 and behavior in the Open Field was evaluated 3 weeks post exposure. RESULTS Treatment with retigabine following 1 LD50 sarin exposure or in combination with TA following 1.2 LD50 exposure significantly reduced mortality rate compared to the non-treated groups. In both experiments, the retigabine treatment significantly reduced gliosis, astrocytosis and brain damage as measured by translocator protein (TSPO). Following sarin exposure the combined treatment (retigabine+ TA) significantly minimized epileptiform seizure activity. Finally, in the Open Field behavioral test the non-treated sarin group showed an increased mobility which was reversed by the combined treatment. CONCLUSIONS The M current modulator retigabine has been shown to be an effective adjunct therapy following OP induced convulsion, minimizing epileptiform seizure activity and attenuating the ensuing brain damage.
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Affiliation(s)
- Ariel Gore
- Department. of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel.
| | - Adi Neufeld-Cohen
- Department. of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Inbal Egoz
- Department. of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Shlomi Baranes
- Department. of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Rellie Gez
- Department. of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Ettie Grauer
- Department. of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Shira Chapman
- Department. of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel
| | - Shlomi Lazar
- Department. of Pharmacology, Israel Institute for Biological Research, Ness Ziona 74100, Israel.
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11
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Racine M, Saleem A, Pick FR. Metabolome Variation between Strains of Microcystis aeruginosa by Untargeted Mass Spectrometry. Toxins (Basel) 2019; 11:E723. [PMID: 31835794 PMCID: PMC6950387 DOI: 10.3390/toxins11120723] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 12/01/2019] [Accepted: 12/04/2019] [Indexed: 12/19/2022] Open
Abstract
Cyanobacteria are notorious for their potential to produce hepatotoxic microcystins (MCs), but other bioactive compounds synthesized in the cells could be as toxic, and thus present interest for characterization. Ultra performance liquid chromatography and high-resolution accurate mass spectrometry (UPLC-QTOF-MS/MS) combined with untargeted analysis was used to compare the metabolomes of five different strains of the common bloom-forming cyanobacterium, Microcystis aeruginosa. Even in microcystin-producing strains, other classes of oligopeptides including cyanopeptolins, aeruginosins, and aerucyclamides, were often the more dominant compounds. The distinct and large variation between strains of the same widespread species highlights the need to characterize the metabolome of a larger number of cyanobacteria, especially as several metabolites other than microcystins can affect ecological and human health.
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Affiliation(s)
- Marianne Racine
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada; (A.S.); (F.R.P.)
- Current address: Environment and Climate Change Canada, Canada Centre for Inland Waters, Burlington, ON L7S 1A1, Canada
| | - Ammar Saleem
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada; (A.S.); (F.R.P.)
| | - Frances R. Pick
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada; (A.S.); (F.R.P.)
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12
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Zare Z, Tehrani M, Zarbakhsh S, Farzadmanesh H, Shafia S, Abedinzade M, Ghanaat A, Mohammadi M. Effects of Paraoxon Exposure on Expression of Apoptosis-Related Genes, Neuronal Survival, and Astrocyte Activation in Rat Prefrontal Cortex. Neurotox Res 2019; 37:356-365. [PMID: 31493121 DOI: 10.1007/s12640-019-00106-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 08/16/2019] [Accepted: 09/02/2019] [Indexed: 01/12/2023]
Abstract
Paraoxon is the bioactive metabolite of organophosphate (OP) pesticide, parathion. This study aimed to evaluate the expression of apoptosis-related genes and histopathological changes in rat prefrontal cortex following exposure to three different doses of paraoxon. Paraoxon (0.3, 0.7, or 1 mg/kg) or corn oil (vehicle) were intraperitoneally injected to adult male Wistar rats. After 14 or 28 days, mRNA and protein levels of Bax, Bcl-2, and caspase-3 were measured in prefrontal cortex using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and western blotting, respectively. In addition, neuronal injury and astrocyte activation were assessed using cresyl violet staining and glial fibrillary acidic protein (GFAP) immune-positive cells, respectively. Treatment with 0.7 and 1 mg/kg of paraoxon increased mRNA and protein levels of Bax and caspase-3 at 14 and 28 days post-exposure, while mRNA and protein levels of Bcl-2 decreased only in 1 mg/kg group after 14 days. Furthermore, a significant decrease in the number of neurons and a significant increase in the number of GFAP-positive cells were observed in rats receiving 0.7 and 1 mg/kg of paraoxon at both time points. Collectively, our results showed that apoptosis is a major mechanism for neuronal damage after exposure to paraoxon. Also, paraoxon-induced neuronal loss was correlated with activation of astrocytes. Since paraoxon-induced neuronal damage is closely related to convulsion, clinical management of convulsion could protect neuronal brain damage.
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Affiliation(s)
- Zohreh Zare
- Department of Anatomical Sciences, Molecular and Cell Biology Research Center, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Mohsen Tehrani
- Department of Immunology, Gastrointestinal Cancer Research Center, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Sam Zarbakhsh
- Nervous System Stem Cells Research Center, Semnan University of Medical Sciences, Semnan, Iran
| | - Hamed Farzadmanesh
- Nervous System Stem Cells Research Center, Semnan University of Medical Sciences, Semnan, Iran
| | - Sakineh Shafia
- Department of Physiology, Molecular and Cell Biology Research Center, School of Medicine, Mazandaran University of Medical Sciences, KM 17 Khazarabad Road, Khazar Sq, Sari, Iran
| | - Mahmood Abedinzade
- Medical Biotechnology Research Center, School of Paramedicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Anahita Ghanaat
- Department of Physiology, Molecular and Cell Biology Research Center, School of Medicine, Mazandaran University of Medical Sciences, KM 17 Khazarabad Road, Khazar Sq, Sari, Iran
| | - Moslem Mohammadi
- Department of Physiology, Molecular and Cell Biology Research Center, School of Medicine, Mazandaran University of Medical Sciences, KM 17 Khazarabad Road, Khazar Sq, Sari, Iran.
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13
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Chapman S, Lazar S, Gez R, Rabinovitz I, Yaakov G, Grauer E. Lung damage following whole body, but not intramuscular, exposure to median lethality dose of sarin: findings in rats and guinea pigs. Inhal Toxicol 2019; 31:203-211. [PMID: 31359796 DOI: 10.1080/08958378.2019.1644402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Objective: Sarin is an irreversible organophosphate cholinesterase inhibitor and a highly toxic, volatile warfare agent. Rats and guinea pigs exposed to sarin display cholinergic excitotoxicity which includes hyper-salivation, respiratory distress, tremors, seizures, and death. Here we focused on the characterization of the airways injury induced by direct exposure of the lungs to sarin vapor and compared it to that induced by the intramuscularly route. Materials and methods: Rats were exposed to sarin either in vapor (∼1LCT50, 34.2 ± 0.8 µg/l/min, 10 min) or by i.m. (∼1LD50, 80 µg/kg), and lung injury was evaluated by broncho-alveolar lavage (BAL). Results and discussion: BAL analysis revealed route-dependent effects in rats: vapor exposed animals showed elevation of inflammatory cytokines, protein, and neutrophil cells. These elevations were seen at 24 h and were still significantly higher compared to control values at 1 week following vapor exposure. These elevations were not detected in rats exposed to sarin i.m. Histological evaluation of the brains revealed typical changes following sarin poisoning independent of the route of administration. The airways damage following vapor exposure in rats was also compared to that induced in guinea pigs. The latter showed increased eosinophilia and histamine levels that constitutes an anaphylactic response not seen in rats. Conclusions: These data clearly point out the importance of using the appropriate route of administration in studying the deleterious effects of volatile nerve agents, as well as the selection of the appropriate animal species. Since airways form major target organs for the development of injury following inhalation toxicity, they should be included in any comprehensive evaluation of countermeasures efficacy.
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Affiliation(s)
- Shira Chapman
- a Department of Pharmacology, Israel Institute for Biological Research (IIBR) , Ness-Ziona , Israel
| | - Shlomi Lazar
- a Department of Pharmacology, Israel Institute for Biological Research (IIBR) , Ness-Ziona , Israel
| | - Rellie Gez
- a Department of Pharmacology, Israel Institute for Biological Research (IIBR) , Ness-Ziona , Israel
| | - Ishai Rabinovitz
- a Department of Pharmacology, Israel Institute for Biological Research (IIBR) , Ness-Ziona , Israel
| | - Guy Yaakov
- a Department of Pharmacology, Israel Institute for Biological Research (IIBR) , Ness-Ziona , Israel
| | - Ettie Grauer
- a Department of Pharmacology, Israel Institute for Biological Research (IIBR) , Ness-Ziona , Israel
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14
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Time dependent dual effect of anti-inflammatory treatments on sarin-induced brain inflammation: Suggested role of prostaglandins. Neurotoxicology 2019; 74:19-27. [PMID: 31095963 DOI: 10.1016/j.neuro.2019.05.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 05/12/2019] [Accepted: 05/12/2019] [Indexed: 11/21/2022]
Abstract
A common consequence of exposure to organophosphate nerve agents is the centrally mediated seizure activity that appears even after conventional treatment with atropine and oximes. We have previously demonstrated a major inflammatory response with subsequent brain damage which was correlated with the duration of the sarin-induced seizures (Chapman et al., 2006). In the present work seizures were induced by the nerve agent sarin (1.2 LD50) insufficiently treated 1 min later by atropine and trimedoxime bromide (TA), with additional midazolam treatment either 5 or 30 min after continuous seizure activity. The efficacy of both steroidal and nonsteroidal anti-inflammatory drugs (NSAIDs), as well as other drugs that were reported as beneficial in neuroprotection, were evaluated for their contribution as adjunct treatment against sarin induced seizures and the ensuing inflammatory brain damage. Results show that both steroids and NSAIDs were harmful when administered during convulsions, and steroids were at best ineffective if administered at their termination. However, if administered at termination of convulsions, the NSAID ibuprofen, the selective COX 2 inhibitor nimesulide and the PLA2 inhibitor quinacrine were partially effective in reducing brain inflammatory markers. Administration of exogenous analogs of prostaglandins (PGE2) immediately following sarin-induced convulsions was found to have a beneficial effect in reducing brain inflammatory markers measured at 24 h and one week post sarin exposure. These findings support the hypothesis that elevated levels of PGE2 have a beneficial role immediately following sarin induced seizures, and that early inhibition of PGE2 production by both steroids and NSAID is contraindicative.
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15
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Deshpande LS, DeLorenzo RJ. Novel therapeutics for treating organophosphate-induced status epilepticus co-morbidities, based on changes in calcium homeostasis. Neurobiol Dis 2019; 133:104418. [PMID: 30872159 DOI: 10.1016/j.nbd.2019.03.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 02/26/2019] [Accepted: 03/09/2019] [Indexed: 11/24/2022] Open
Abstract
Organophosphate (OP) chemicals include pesticides such as parathion, and nerve gases such as sarin and soman and are considered major chemical threat agents. Acute OP exposure is associated with a cholinergic crisis and status epilepticus (SE). It is also known that the survivors of OP toxicity exhibit neurobehavioral deficits such as mood changes, depression, and memory impairment, and acquired epilepsy. Our research has focused on addressing the need to develop effective therapeutic agents that could be administered even after prolonged seizures and would prevent or lessen the chronic morbidity associated with OP-SE survival. We have developed rat survival models of OP pesticide metabolite paraoxon (POX) and nerve agent sarin surrogate diisopropyl fluorophosphate (DFP) induced SE that are being used to screen for medical countermeasures against an OP attack. Our research has focused on studying neuronal calcium (Ca2+) homeostatic mechanisms for identifying mechanisms and therapeutics for the expression of neurological morbidities associated with OP-SE survival. We have observed development of a "Ca2+ plateau" characterized by sustained elevations in neuronal Ca2+ levels in OP-SE surviving rats that coincided with the appearance of OP-SE chronic morbidities. These Ca2+ elevations had their origin in Ca2+ release from the intracellular stores such that blockade with antagonists like dantrolene, carisbamate, and levetiracetam lowered OP-SE mediated Ca2+ plateau and afforded significant neuroprotection. Since the Ca2+ plateau lasts for a prolonged period, our studies suggest that blocking it after the control of SE may represent a unique target for development of novel countermeasures to prevent long term Ca2+ mediated OP-SE neuropsychiatric comorbidities such as depression, anxiety, and acquired epilepsy (AE).
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Affiliation(s)
- Laxmikant S Deshpande
- Department of Neurology, Virginia Commonwealth University, Richmond, VA 23298, USA; Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Robert J DeLorenzo
- Department of Neurology, Virginia Commonwealth University, Richmond, VA 23298, USA; Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA.
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16
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Early changes in M2 muscarinic acetylcholine receptors (mAChRs) induced by sarin intoxication may be linked to long lasting neurological effects. Neurotoxicology 2017; 65:248-254. [PMID: 29128314 DOI: 10.1016/j.neuro.2017.11.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 11/05/2017] [Accepted: 11/05/2017] [Indexed: 01/08/2023]
Abstract
The effect of sarin on the binding parameters (KD & Bmax) of M2 muscarinic acetylcholine receptor (mAChR) was studied 24h and 1 week post exposure. Male & female Sprague-Daweley rats were poisoned with 1XLD50 sarin (80μg/kg, im) followed by treatment of trimedoxime bromide and atropine (7.5:5mg/kg, im) 1min later. Brains were removed and analyzed for M2 mAChR binding, using [3H]AFDX384, an M2 selective antagonist. A significant increase in KD of M2 mAChR was found in the cortex 24h post poisoning, displaying elevation from 4.65±1.16 to 8.45±1.06nM and 5.24±0.93 to 9.29±1.56nM in male and female rats, respectively. A rise in KD was also noted 1 week following exposure from 5.04±1.20 to 11.75±2.78 and from 5.37±1.02 to 11.66±1.73nM, presenting an added increase of 51 and 40% (compared to 24h) in males and females, respectively. Analysis of M2 receptor density (Bmax) revealed a significant reduction of 68% in males and insignificant reduction of 22% in females, 24h after sarin exposure which was followed by 37% recovery in males and 100% recovery in females, 1 week later. These results indicate that sarin induces a long-term decreased affinity in M2 mAChR (elevated KDs) and a transient effect on the number of this receptor subtype (Bmax). We hypothesize that the reduced affinity of the M2 receptors (negative auto-regulatory receptors) may cause long-term brain deficits by impairing the normal regulation release of ACh into the synaptic cleft.
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17
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Differential expression of glutamate transporters in cerebral cortex of paraoxon-treated rats. Neurotoxicol Teratol 2017; 62:20-26. [PMID: 28603072 DOI: 10.1016/j.ntt.2017.06.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 05/12/2017] [Accepted: 06/07/2017] [Indexed: 01/05/2023]
Abstract
Glutamatergic system is involved in pathological effects of organophosphorus (OP) compounds. We aimed to determine in vivo effects of paraoxon, the bioactive metabolite of parathion, on the expression of glutamate transporters as well as Bax and Bcl2 in rat cerebral cortex. Male Wistar rats received an intraperitoneal (i.p.) injection of one of three doses of paraoxon (0.3, 0.7, or 1mg/kg) or corn oil as vehicle (1ml/kg). After 4 or 18h, cerebral cortices were dissected out and used for quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and western blot assays to measure mRNA and protein levels, respectively. The cortical glial glutamate transporters (GLAST and GLT-1) were up-regulated in animals treated with 0.7mg/kg of paraoxon, but down-regulated in 1mg/kg group. Neuronal glutamate transporter (EAAC1) was unchanged in 0.7mg/kg treated rats, while reduced in 1mg/kg group. No significant difference was found in the mRNA and protein expression of EAAC1 in animals intoxicated with 0.3mg/kg of paraoxon. Paraoxon (1mg/kg) resulted in an up-regulation of Bax and down-regulation of Bcl2 mRNA levels in the rat cerebral cortex. These results indicate that paraoxon can differentially regulate expression of glutamate transporters at mRNA and protein levels in the cerebral cortex. Changes in the expression of glutamate transporters are closely related to paraoxon-induced seizure activity.
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