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Hobson BA, Rowland DJ, Dou Y, Saito N, Harmany ZT, Bruun DA, Harvey DJ, Chaudhari AJ, Garbow JR, Lein PJ. A longitudinal MRI and TSPO PET-based investigation of brain region-specific neuroprotection by diazepam versus midazolam following organophosphate-induced seizures. Neuropharmacology 2024; 251:109918. [PMID: 38527652 PMCID: PMC11250911 DOI: 10.1016/j.neuropharm.2024.109918] [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: 11/29/2023] [Revised: 03/01/2024] [Accepted: 03/13/2024] [Indexed: 03/27/2024]
Abstract
Acute poisoning with organophosphorus cholinesterase inhibitors (OPs), such as OP nerve agents and pesticides, can cause life threatening cholinergic crisis and status epilepticus (SE). Survivors often experience significant morbidity, including brain injury, acquired epilepsy, and cognitive deficits. Current medical countermeasures for acute OP poisoning include a benzodiazepine to mitigate seizures. Diazepam was long the benzodiazepine included in autoinjectors used to treat OP-induced seizures, but it is now being replaced in many guidelines by midazolam, which terminates seizures more quickly, particularly when administered intramuscularly. While a direct correlation between seizure duration and the extent of brain injury has been widely reported, there are limited data comparing the neuroprotective efficacy of diazepam versus midazolam following acute OP intoxication. To address this data gap, we used non-invasive imaging techniques to longitudinally quantify neuropathology in a rat model of acute intoxication with the OP diisopropylfluorophosphate (DFP) with and without post-exposure intervention with diazepam or midazolam. Magnetic resonance imaging (MRI) was used to monitor neuropathology and brain atrophy, while positron emission tomography (PET) with a radiotracer targeting translocator protein (TSPO) was utilized to assess neuroinflammation. Animals were scanned at 3, 7, 28, 65, 91, and 168 days post-DFP and imaging metrics were quantitated for the hippocampus, amygdala, piriform cortex, thalamus, cerebral cortex and lateral ventricles. In the DFP-intoxicated rat, neuroinflammation persisted for the duration of the study coincident with progressive atrophy and ongoing tissue remodeling. Benzodiazepines attenuated neuropathology in a region-dependent manner, but neither benzodiazepine was effective in attenuating long-term neuroinflammation as detected by TSPO PET. Diffusion MRI and TSPO PET metrics were highly correlated with seizure severity, and early MRI and PET metrics were positively correlated with long-term brain atrophy. Collectively, these results suggest that anti-seizure therapy alone is insufficient to prevent long-lasting neuroinflammation and tissue remodeling.
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Affiliation(s)
- Brad A Hobson
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA; Center for Molecular and Genomic Imaging, University of California, Davis, College of Engineering, Davis, CA 95616, USA.
| | - Douglas J Rowland
- Center for Molecular and Genomic Imaging, University of California, Davis, College of Engineering, Davis, CA 95616, USA.
| | - Yimeng Dou
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA.
| | - Naomi Saito
- Department of Public Health Sciences, University of California, Davis, School of Medicine, California 95616, USA.
| | - Zachary T Harmany
- Center for Molecular and Genomic Imaging, University of California, Davis, College of Engineering, Davis, CA 95616, USA.
| | - Donald A Bruun
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA.
| | - Danielle J Harvey
- Department of Public Health Sciences, University of California, Davis, School of Medicine, California 95616, USA.
| | - Abhijit J Chaudhari
- Center for Molecular and Genomic Imaging, University of California, Davis, College of Engineering, Davis, CA 95616, USA; Department of Radiology, University of California, Davis, School of Medicine, California 95817, USA.
| | - Joel R Garbow
- Biomedical Magnetic Resonance Center, Mallinckrodt Institute of Radiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, 63110, USA.
| | - Pamela J Lein
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA.
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2
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Bernardino PN, Luo AS, Andrew PM, Unkel CM, Gonzalez MI, Gelli A, Lein PJ. Evidence Implicating Blood-Brain Barrier Impairment in the Pathogenesis of Acquired Epilepsy following Acute Organophosphate Intoxication. J Pharmacol Exp Ther 2024; 388:301-312. [PMID: 37827702 PMCID: PMC10801776 DOI: 10.1124/jpet.123.001836] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 09/14/2023] [Accepted: 09/18/2023] [Indexed: 10/14/2023] Open
Abstract
Organophosphate (OP) poisoning can trigger cholinergic crisis, a life-threatening toxidrome that includes seizures and status epilepticus. These acute toxic responses are associated with persistent neuroinflammation and spontaneous recurrent seizures (SRS), also known as acquired epilepsy. Blood-brain barrier (BBB) impairment has recently been proposed as a pathogenic mechanism linking acute OP intoxication to chronic adverse neurologic outcomes. In this review, we briefly describe the cellular and molecular components of the BBB, review evidence of altered BBB integrity following acute OP intoxication, and discuss potential mechanisms by which acute OP intoxication may promote BBB dysfunction. We highlight the complex interplay between neuroinflammation and BBB dysfunction that suggests a positive feedforward interaction. Lastly, we examine research from diverse models and disease states that suggest mechanisms by which loss of BBB integrity may contribute to epileptogenic processes. Collectively, the literature identifies BBB impairment as a convergent mechanism of neurologic disease and justifies further mechanistic research into how acute OP intoxication causes BBB impairment and its role in the pathogenesis of SRS and potentially other long-term neurologic sequelae. Such research is critical for evaluating BBB stabilization as a neuroprotective strategy for mitigating OP-induced epilepsy and possibly seizure disorders of other etiologies. SIGNIFICANCE STATEMENT: Clinical and preclinical studies support a link between blood-brain barrier (BBB) dysfunction and epileptogenesis; however, a causal relationship has been difficult to prove. Mechanistic studies to delineate relationships between BBB dysfunction and epilepsy may provide novel insights into BBB stabilization as a neuroprotective strategy for mitigating epilepsy resulting from acute organophosphate (OP) intoxication and non-OP causes and potentially other adverse neurological conditions associated with acute OP intoxication, such as cognitive impairment.
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Affiliation(s)
- Pedro N Bernardino
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, California (P.N.B., A.S.L., P.M.A., C.M.U., P.J.L.); Department of Neurology, University of California, Davis, School of Medicine, Sacramento, California (M.I.G.); and Department of Pharmacology, University of California, Davis, School of Medicine, Davis, California (A.G.)
| | - Audrey S Luo
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, California (P.N.B., A.S.L., P.M.A., C.M.U., P.J.L.); Department of Neurology, University of California, Davis, School of Medicine, Sacramento, California (M.I.G.); and Department of Pharmacology, University of California, Davis, School of Medicine, Davis, California (A.G.)
| | - Peter M Andrew
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, California (P.N.B., A.S.L., P.M.A., C.M.U., P.J.L.); Department of Neurology, University of California, Davis, School of Medicine, Sacramento, California (M.I.G.); and Department of Pharmacology, University of California, Davis, School of Medicine, Davis, California (A.G.)
| | - Chelsea M Unkel
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, California (P.N.B., A.S.L., P.M.A., C.M.U., P.J.L.); Department of Neurology, University of California, Davis, School of Medicine, Sacramento, California (M.I.G.); and Department of Pharmacology, University of California, Davis, School of Medicine, Davis, California (A.G.)
| | - Marco I Gonzalez
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, California (P.N.B., A.S.L., P.M.A., C.M.U., P.J.L.); Department of Neurology, University of California, Davis, School of Medicine, Sacramento, California (M.I.G.); and Department of Pharmacology, University of California, Davis, School of Medicine, Davis, California (A.G.)
| | - Angie Gelli
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, California (P.N.B., A.S.L., P.M.A., C.M.U., P.J.L.); Department of Neurology, University of California, Davis, School of Medicine, Sacramento, California (M.I.G.); and Department of Pharmacology, University of California, Davis, School of Medicine, Davis, California (A.G.)
| | - Pamela J Lein
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, California (P.N.B., A.S.L., P.M.A., C.M.U., P.J.L.); Department of Neurology, University of California, Davis, School of Medicine, Sacramento, California (M.I.G.); and Department of Pharmacology, University of California, Davis, School of Medicine, Davis, California (A.G.)
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3
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Bernardino PN, Hobson BA, Huddleston SL, Andrew PM, MacMahon JA, Saito NH, Porter VA, Bruun DA, Harvey DJ, Garbow JR, Gelli A, Chaudhari AJ, Lein PJ. Time- and region-dependent blood-brain barrier impairment in a rat model of organophosphate-induced status epilepticus. Neurobiol Dis 2023; 187:106316. [PMID: 37797902 PMCID: PMC11000668 DOI: 10.1016/j.nbd.2023.106316] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 09/26/2023] [Accepted: 10/02/2023] [Indexed: 10/07/2023] Open
Abstract
Acute organophosphate (OP) intoxication can trigger seizures that progress to status epilepticus (SE), and survivors often develop chronic morbidities, including spontaneous recurrent seizures (SRS). The pathogenic mechanisms underlying OP-induced SRS are unknown, but increased BBB permeability is hypothesized to be involved. Previous studies reported BBB leakage following OP-induced SE, but key information regarding time and regional distribution of BBB impairment during the epileptogenic period is missing. To address this data gap, we characterized the spatiotemporal progression of BBB impairment during the first week post-exposure in a rat model of diisopropylfluorophosphate-induced SE, using MRI and albumin immunohistochemistry. Increased BBB permeability, which was detected at 6 h and persisted up to 7 d post-exposure, was most severe and persistent in the piriform cortex and amygdala, moderate but persistent in the thalamus, and less severe and transient in the hippocampus and somatosensory cortex. The extent of BBB leakage was positively correlated with behavioral seizure severity, with the strongest association identified in the piriform cortex and amygdala. These findings provide evidence of the duration, magnitude and spatial breakdown of the BBB during the epileptogenic period following OP-induced SE and support BBB regulation as a viable therapeutic target for preventing SRS following acute OP intoxication.
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Affiliation(s)
- Pedro N Bernardino
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA.
| | - Brad A Hobson
- Center for Molecular and Genomic Imaging, University of California, Davis, Davis, CA 95616, USA.
| | - Sydney L Huddleston
- Center for Molecular and Genomic Imaging, University of California, Davis, Davis, CA 95616, USA.
| | - Peter M Andrew
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA.
| | - Jeremy A MacMahon
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA.
| | - Naomi H Saito
- Department of Public Health Sciences, University of California, Davis, School of Medicine, Davis, CA 95616, USA.
| | - Valerie A Porter
- Department of Biomedical Engineering, University of California, Davis, College of Engineering, Davis, CA 95616, USA.
| | - Donald A Bruun
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA.
| | - Danielle J Harvey
- Department of Public Health Sciences, University of California, Davis, School of Medicine, Davis, CA 95616, USA.
| | - Joel R Garbow
- Biomedical Magnetic Resonance Center, Mallinckrodt Institute of Radiology, School of Medicine, Washington University in St. Louis, St. Louis, MO 63110, USA.
| | - Angie Gelli
- Department of Pharmacology, University of California, Davis, School of Medicine, Davis, CA 95616, USA.
| | - Abhijit J Chaudhari
- Center for Molecular and Genomic Imaging, University of California, Davis, Davis, CA 95616, USA; Department of Radiology, University of California, Davis, School of Medicine, Sacramento, CA 95817, USA.
| | - Pamela J Lein
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA.
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Shi J, Liu D, Jin Q, Chen X, Zhang R, Shi T, Zhu S, Zhang Y, Zong X, Wang C, Li L. Whole-Transcriptome Analysis of Repeated Low-Level Sarin-Exposed Rat Hippocampus and Identification of Cerna Networks to Investigate the Mechanism of Sarin-Induced Cognitive Impairment. BIOLOGY 2023; 12:biology12040627. [PMID: 37106826 PMCID: PMC10136365 DOI: 10.3390/biology12040627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 04/12/2023] [Accepted: 04/17/2023] [Indexed: 04/29/2023]
Abstract
Sarin is a potent organophosphorus nerve agent that causes cognitive dysfunction, but its underlying molecular mechanisms are poorly understood. In this study, a rat model of repeated low-level sarin exposure was established using the subcutaneous injection of 0.4 × LD50 for 21 consecutive days. Sarin-exposed rats showed persistent learning and memory impairment and reduced hippocampal dendritic spine density. A whole-transcriptome analysis was applied to study the mechanism of sarin-induced cognitive impairment, and a total of 1035 differentially expressed mRNA (DEmRNA), including 44 DEmiRNA, 305 DElncRNA, and 412 DEcircRNA, were found in the hippocampus of sarin-treated rats. According to Gene Ontology (GO) annotation, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and Protein-Protein Interaction (PPI) analysis, these DERNAs were mainly involved in neuronal synaptic plasticity and were related to the pathogenesis of neurodegenerative diseases. The circRNA/lncRNA-miRNA-mRNA ceRNA network was constructed, in which Circ_Fmn1, miR-741-3p, miR-764-3p, miR-871-3p, KIF1A, PTPN11, SYN1, and MT-CO3 formed one circuit, and Circ_Cacna1c, miR-10b-5p, miR-18a-5p, CACNA1C, PRKCD, and RASGRP1 constituted another circuit. The balance between the two circuits was crucial for maintaining synaptic plasticity and may be the regulatory mechanism by which sarin causes cognitive impairment. Our study reveals the ceRNA regulation mechanism of sarin exposure for the first time and provides new insights into the molecular mechanisms of other organophosphorus toxicants.
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Affiliation(s)
- Jingjing Shi
- State Key Laboratory of NBC Protection for Civilians, Beijing 102205, China
| | - Dongxin Liu
- State Key Laboratory of NBC Protection for Civilians, Beijing 102205, China
| | - Qian Jin
- State Key Laboratory of NBC Protection for Civilians, Beijing 102205, China
| | - Xuejun Chen
- State Key Laboratory of NBC Protection for Civilians, Beijing 102205, China
| | - Ruihua Zhang
- State Key Laboratory of NBC Protection for Civilians, Beijing 102205, China
| | - Tong Shi
- State Key Laboratory of NBC Protection for Civilians, Beijing 102205, China
| | - Siqing Zhu
- State Key Laboratory of NBC Protection for Civilians, Beijing 102205, China
| | - Yi Zhang
- State Key Laboratory of NBC Protection for Civilians, Beijing 102205, China
| | - Xingxing Zong
- State Key Laboratory of NBC Protection for Civilians, Beijing 102205, China
| | - Chen Wang
- State Key Laboratory of NBC Protection for Civilians, Beijing 102205, China
| | - Liqin Li
- State Key Laboratory of NBC Protection for Civilians, Beijing 102205, China
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5
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Neurotoxicity evoked by organophosphates and available countermeasures. Arch Toxicol 2023; 97:39-72. [PMID: 36335468 DOI: 10.1007/s00204-022-03397-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 10/11/2022] [Indexed: 11/07/2022]
Abstract
Organophosphorus compounds (OP) are a constant problem, both in the military and in the civilian field, not only in the form of acute poisoning but also for their long-lasting consequences. No antidote has been found that satisfactorily protects against the toxic effects of organophosphates. Likewise, there is no universal cure to avert damage after poisoning. The key mechanism of organophosphate toxicity is the inhibition of acetylcholinesterase. The overstimulation of nicotinic or muscarinic receptors by accumulated acetylcholine on a synaptic cleft leads to activation of the glutamatergic system and the development of seizures. Further consequences include generation of reactive oxygen species (ROS), neuroinflammation, and the formation of various other neuropathologists. In this review, we present neuroprotection strategies which can slow down the secondary nerve cell damage and alleviate neurological and neuropsychiatric disturbance. In our opinion, there is no unequivocal approach to ensure neuroprotection, however, sooner the neurotoxicity pathway is targeted, the better the results which can be expected. It seems crucial to target the key propagation pathways, i.e., to block cholinergic and, foremostly, glutamatergic cascades. Currently, the privileged approach oriented to stimulating GABAAR by benzodiazepines is of limited efficacy, so that antagonizing the hyperactivity of the glutamatergic system could provide an even more efficacious approach for terminating OP-induced seizures and protecting the brain from permanent damage. Encouraging results have been reported for tezampanel, an antagonist of GluK1 kainate and AMPA receptors, especially in combination with caramiphen, an anticholinergic and anti-glutamatergic agent. On the other hand, targeting ROS by antioxidants cannot or already developed neuroinflammation does not seem to be very productive as other processes are also involved.
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6
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Ibrahim WW, Sayed RH, Kandil EA, Wadie W. Niacin mitigates blood-brain barrier tight junctional proteins dysregulation and cerebral inflammation in ketamine rat model of psychosis: Role of GPR109A receptor. Prog Neuropsychopharmacol Biol Psychiatry 2022; 119:110583. [PMID: 35690118 DOI: 10.1016/j.pnpbp.2022.110583] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 06/05/2022] [Accepted: 06/05/2022] [Indexed: 01/25/2023]
Abstract
Dysregulated inflammatory responses and blood-brain barrier (BBB) dysfunction are recognized as central factors in the development of psychiatric disorders. The present study was designed to evaluate the effect of niacin on BBB integrity in ketamine-induced model of psychosis. Meanwhile, mepenzolate bromide (MPN), a GPR109A receptor blocker, was used to investigate the role of this receptor on the observed niacin's effect. Male Wistar rats received ketamine (30 mg/kg/day, i.p) for 5 consecutive days and then niacin (40 mg/kg/day, p.o), with or without MPN (5 mg/kg/day, i.p), was given for the subsequent 15 days. Three days before the end of experiment, rats were behaviorally tested using open field, novel object recognition, social interaction, and forced swimming tests. Niacin significantly ameliorated ketamine-induced behavioral deficits, amended gamma aminobutyric acid and glutamate concentration, decreased tumor necrosis factor-α and matrix metallopeptidase 9 levels, and increased netrin-1 contents in the hippocampus of rats. Niacin also augmented the hippocampal expression of ZO-1, occludin, and claudin-5 proteins, indicating the ability of niacin to restore the BBB integrity. Moreover, the histopathologic changes in hippocampal neurons were alleviated. Since all the beneficial effects of niacin in the present investigation were partially abolished by the co-administration of MPN; GPR109A receptor was proven to partially mediate the observed antipsychotic effects of niacin. These data revealed that GPR109A-mediated signaling pathways might represent potential targets for therapeutic interventions to prevent or slow the progression of psychosis.
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Affiliation(s)
- Weam W Ibrahim
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Egypt
| | - Rabab H Sayed
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Egypt.
| | - Esraa A Kandil
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Egypt
| | - Walaa Wadie
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Egypt
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Venkatasamy L, Nizamutdinov D, Jenkins J, Shapiro LA. Vagus Nerve Stimulation Ameliorates Cognitive Impairment and Increased Hippocampal Astrocytes in a Mouse Model of Gulf War Illness. Neurosci Insights 2021; 16:26331055211018456. [PMID: 34104886 PMCID: PMC8165814 DOI: 10.1177/26331055211018456] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 04/29/2021] [Indexed: 01/17/2023] Open
Abstract
Gulf war illness (GWI), is a chronic multi-symptom illness that has impacted approximately one-third of the veterans who served in the 1990 to 1991 Gulf War. GWI symptoms include cognitive impairments (eg, memory and concentration problems), headaches, migraines, fatigue, gastrointestinal and respiratory issues, as well as emotional deficits. The exposure to neurological chemicals such as the anti-nerve gas drug, pyridostigmine bromide (PB), and the insecticide permethrin (PER), may contribute to the etiologically related factors of GWI. Various studies utilizing mouse models of GWI have reported the interplay of these chemical agents in increasing neuroinflammation and cognitive dysfunction. Astrocytes are involved in the secretion of neuroinflammatory cytokines and chemokines in pathological conditions and have been implicated in GWI symptomology. We hypothesized that exposure to PB and PER causes lasting changes to hippocampal astrocytes, concurrent with chronic cognitive deficits that can be reversed by cervical vagus nerve stimulation (VNS). GWI was induced in CD1 mice by injecting the mixture of PER (200 mg/kg) and PB (2 mg/kg), i.p. for 10 consecutive days. VNS stimulators were implanted at 33 weeks after GWI induction. The results show age-related cognitive alterations at approximately 9 months after exposure to PB and PER. The results also showed an increased number of GFAP-labeled astrocytes in the hippocampus and dentate gyrus that was ameliorated by VNS.
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Affiliation(s)
- Lavanya Venkatasamy
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University, Bryan, TX, USA
| | - Damir Nizamutdinov
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University, Bryan, TX, USA
| | - Jaclyn Jenkins
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University, Bryan, TX, USA
| | - Lee A Shapiro
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University, Bryan, TX, USA
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Madhu LN, Kodali M, Attaluri S, Shuai B, Melissari L, Rao X, Shetty AK. Melatonin improves brain function in a model of chronic Gulf War Illness with modulation of oxidative stress, NLRP3 inflammasomes, and BDNF-ERK-CREB pathway in the hippocampus. Redox Biol 2021; 43:101973. [PMID: 33933884 PMCID: PMC8105671 DOI: 10.1016/j.redox.2021.101973] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 04/05/2021] [Accepted: 04/09/2021] [Indexed: 02/07/2023] Open
Abstract
Persistent cognitive and mood dysfunction is the primary CNS symptom in veterans afflicted with Gulf War Illness (GWI). This study investigated the efficacy of melatonin (MEL) for improving cognitive and mood function with antioxidant, antiinflammatory, and pro-cognitive effects in a rat model of chronic GWI. Six months after exposure to GWI-related chemicals and stress, rats were treated with vehicle or MEL (5, 10, 20, 40, and 80 mg/kg) for eight weeks. Behavioral tests revealed cognitive and mood dysfunction in GWI rats receiving vehicle, which were associated with elevated oxidative stress, reduced NRF2, catalase and mitochondrial complex proteins, astrocyte hypertrophy, activated microglia with NLRP3 inflammasomes, elevated proinflammatory cytokines, waned neurogenesis, and synapse loss in the hippocampus. MEL at 10 mg/kg alleviated simple and associative recognition memory dysfunction and anhedonia, along with reduced oxidative stress, enhanced glutathione and complex III, and reduced NLRP3 inflammasomes, IL-18, TNF-α, and IFN-γ. MEL at 20 mg/kg also normalized NRF2 and catalase and increased microglial ramification. MEL at 40 mg/kg, in addition, reduced astrocyte hypertrophy, activated microglia, NF-kB-NLRP3-caspase-1 signaling, IL-1β, MCP-1, and MIP-1α. Moreover, MEL at 80 mg/kg activated the BDNF-ERK-CREB signaling pathway, enhanced neurogenesis and diminished synapse loss in the hippocampus, and improved a more complex hippocampus-dependent cognitive function. Thus, MEL therapy is efficacious for improving cognitive and mood function in a rat model of chronic GWI, and MEL's effect was dose-dependent. The study provides the first evidence of MEL's promise for alleviating neuroinflammation and cognitive and mood impairments in veterans with chronic GWI. A low dose of Melatonin alleviated recognition memory dysfunction and anhedonia in a model of chronic GWI. A moderate dose of Melatonin improved more complex cognitive function in a model of chronic GWI. Melatonin treatment reduced oxidative stress and enhanced mitochondrial complex proteins in the GWI brain. Melatonin inhibited NLRP3 inflammasomes and proinflammatory cytokines in the GWI brain. Melatonin activated the BDNF-ERK-CREB signaling pathway and enhanced neurogenesis in the GWI brain.
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Affiliation(s)
- Leelavathi N Madhu
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA
| | - Maheedhar Kodali
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA
| | - Sahithi Attaluri
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA
| | - Bing Shuai
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA
| | - Laila Melissari
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA
| | - Xiaolan Rao
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA
| | - Ashok K Shetty
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA.
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9
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Tras B, Eser Faki H, Ozdemir Kutahya Z, Bahcivan E, Dik B, Bozkurt B, Uney K. Treatment and protective effects of metalloproteinase inhibitors alone and in combination with N-Acetyl cysteine plus vitamin E in rats exposed to aflatoxin B 1. Toxicon 2021; 194:79-85. [PMID: 33617885 DOI: 10.1016/j.toxicon.2021.02.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 02/08/2021] [Accepted: 02/16/2021] [Indexed: 11/19/2022]
Abstract
This study was conducted to investigate the effects of matrix metalloproteinase (MMP) inhibitors dexamethasone and minocycline administrations -both single and in combination with N-acetylcysteine (NAC) and vitamin E-on the tissue distribution and lethal dose (LD)50 of aflatoxin (AF)B1 in rats. We performed this study on male Wistar rats (8-10 weeks) in two phases. In the first phase, rats were administered dexamethasone (5 and 20 mg/kg) and minocycline (45 and 90 mg/kg), both as single treatments and in combination with NAC (200 mg/kg) and vitamin E (600 mg/kg); these treatments followed AFB1 administration (2 mg/kg). In the second phase, the therapeutic effect value (TEV) was calculated to determine the treatment effect on the LD50 level of AFB1. The tissue affinity of AFB1 from high to low was liver, kidney, intestine, brain, heart, spleen, lung, testis, and vitreous humor, respectively. Dexamethasone at the 20 mg/kg dose significantly reduced AFB1 concentrations in the plasma and the other tissues, except for the vitreous humor. The effects of minocycline on the plasma and tissue concentrations of AFB1 varied by dose and tissue. The combinations of dexamethasone or minocycline with NAC and vitamin E increased the AFB1 concentrations in the plasma and all tissues, except for vitreous humor and liver. In male rats, the LD50 value of AFB1 was 11.86 mg/kg. The TEV of dexamethasone (20 mg/kg) was calculated to be 1.5. Dexamethasone can be administered in repeated doses at ≥20 mg/kg to increase survival in AFB1 poisoning.
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Affiliation(s)
- Bunyamin Tras
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Selcuk, 42031, Konya, Turkey
| | - Hatice Eser Faki
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Selcuk, 42031, Konya, Turkey
| | - Zeynep Ozdemir Kutahya
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Cukurova, 01930, Adana, Turkey
| | - Emre Bahcivan
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Kafkas, 36000, Kars, Turkey
| | - Burak Dik
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Selcuk, 42031, Konya, Turkey.
| | - Banu Bozkurt
- Department of Ophthalmology, Faculty of Medicine, University of Selcuk, 42031, Konya, Turkey
| | - Kamil Uney
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Selcuk, 42031, Konya, Turkey
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10
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Sex-Based Differences in Plasma Autoantibodies to Central Nervous System Proteins in Gulf War Veterans versus Healthy and Symptomatic Controls. Brain Sci 2021; 11:brainsci11020148. [PMID: 33498629 PMCID: PMC7911379 DOI: 10.3390/brainsci11020148] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 01/08/2021] [Accepted: 01/20/2021] [Indexed: 02/07/2023] Open
Abstract
Veterans from the 1991 Gulf War (GW) have suffered from Gulf War illness (GWI) for nearly 30 years. This illness encompasses multiple body systems, including the central nervous system (CNS). Diagnosis and treatment of GWI is difficult because there has not been an objective diagnostic biomarker. Recently, we reported on a newly developed blood biomarker that discriminates GWI from GW healthy controls, and symptomatic controls with irritable bowel syndrome (IBS) and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). The present study was designed to compare levels of these biomarkers between men and women with GWI, as well as sex-specific effects in comparison to healthy GW veterans and symptomatic controls (IBS, ME/CFS). The results showed that men and women with GWI differ in 2 of 10 plasma autoantibodies, with men showing significantly elevated levels. Men and women with GWI showed significantly different levels of autoantibodies in 8 of 10 biomarkers to neuronal and glial proteins in plasma relative to controls. In summary, the present study addressed the utility of the use of plasma autoantibodies for CNS proteins to distinguish among both men and women veterans with GWI and other healthy and symptomatic control groups.
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11
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Abou-Donia MB, Lapadula ES, Krengel MH, Quinn E, LeClair J, Massaro J, Conboy LA, Kokkotou E, Abreu M, Klimas NG, Nguyen DD, Sullivan K. Using Plasma Autoantibodies of Central Nervous System Proteins to Distinguish Veterans with Gulf War Illness from Healthy and Symptomatic Controls. Brain Sci 2020; 10:brainsci10090610. [PMID: 32899468 PMCID: PMC7563126 DOI: 10.3390/brainsci10090610] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 08/31/2020] [Accepted: 09/01/2020] [Indexed: 01/02/2023] Open
Abstract
For the past 30 years, there has been a lack of objective tools for diagnosing Gulf War Illness (GWI), which is largely characterized by central nervous system (CNS) symptoms emerging from 1991 Gulf War (GW) veterans. In a recent preliminary study, we reported the presence of autoantibodies against CNS proteins in the blood of veterans with GWI, suggesting a potential objective biomarker for the disorder. Now, we report the results of a larger, confirmatory study of these objective biomarkers in 171 veterans with GWI compared to 60 healthy GW veteran controls and 85 symptomatic civilian controls (n = 50 myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and n = 35 irritable bowel syndrome (IBS)). Specifically, we compared plasma markers of CNS autoantibodies for diagnostic characteristics of the four groups (GWI, GW controls, ME/CFS, IBS). For veterans with GWI, the results showed statistically increased levels of nine of the ten autoantibodies against neuronal "tubulin, neurofilament protein (NFP), Microtubule Associated Protein-2 (MAP-2), Microtubule Associated Protein-Tau (Tau), alpha synuclein (α-syn), calcium calmodulin kinase II (CaMKII)" and glial proteins "Glial Fibrillary Acidic Protein (GFAP), Myelin Associated Glycoprotein (MAG), Myelin Basic Protein (MBP), S100B" compared to healthy GW controls as well as civilians with ME/CFS and IBS. Next, we summed all of the means of the CNS autoantibodies for each group into a new index score called the Neurodegeneration Index (NDI). The NDI was calculated for each tested group and showed veterans with GWI had statistically significantly higher NDI values than all three control groups. The present study confirmed the utility of the use of plasma autoantibodies for CNS proteins to distinguish among veterans with GWI and other healthy and symptomatic control groups.
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Affiliation(s)
- Mohamed B. Abou-Donia
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA;
- Correspondence: (M.B.A.-D.); (K.S.); Tel.: +1-919-684-2221 (M.B.A.-D.)
| | - Elizabeth S. Lapadula
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA;
| | - Maxine H. Krengel
- Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA;
| | - Emily Quinn
- Departments of Biostatistics and Environmental Health, Boston University School of Public Health, Boston, MA 02118, USA; (E.Q.); (J.L.); (J.M.); (D.D.N.)
| | - Jessica LeClair
- Departments of Biostatistics and Environmental Health, Boston University School of Public Health, Boston, MA 02118, USA; (E.Q.); (J.L.); (J.M.); (D.D.N.)
| | - Joseph Massaro
- Departments of Biostatistics and Environmental Health, Boston University School of Public Health, Boston, MA 02118, USA; (E.Q.); (J.L.); (J.M.); (D.D.N.)
| | - Lisa A. Conboy
- Department of Medicine, Harvard Medical School, Boston, MA 02115, USA; (L.A.C.); (E.K.)
| | - Efi Kokkotou
- Department of Medicine, Harvard Medical School, Boston, MA 02115, USA; (L.A.C.); (E.K.)
| | - Maria Abreu
- Dr. Kiran C. Patel College of Osteopathic Medicine, Institute for Neuroimmune Medicine, Nova Southeastern University, Fort Lauderdale, FL 33314, USA; (M.A.); (N.G.K.)
- Department of Immunology, Miami VA Medical Center, Miami, FL 33125, USA
| | - Nancy G. Klimas
- Dr. Kiran C. Patel College of Osteopathic Medicine, Institute for Neuroimmune Medicine, Nova Southeastern University, Fort Lauderdale, FL 33314, USA; (M.A.); (N.G.K.)
- Department of Immunology, Miami VA Medical Center, Miami, FL 33125, USA
| | - Daniel D. Nguyen
- Departments of Biostatistics and Environmental Health, Boston University School of Public Health, Boston, MA 02118, USA; (E.Q.); (J.L.); (J.M.); (D.D.N.)
| | - Kimberly Sullivan
- Departments of Biostatistics and Environmental Health, Boston University School of Public Health, Boston, MA 02118, USA; (E.Q.); (J.L.); (J.M.); (D.D.N.)
- Correspondence: (M.B.A.-D.); (K.S.); Tel.: +1-919-684-2221 (M.B.A.-D.)
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12
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The Low Glutamate Diet Effectively Improves Pain and Other Symptoms of Gulf War Illness. Nutrients 2020; 12:nu12092593. [PMID: 32859032 PMCID: PMC7551234 DOI: 10.3390/nu12092593] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/17/2020] [Accepted: 08/20/2020] [Indexed: 01/19/2023] Open
Abstract
Gulf War Illness (GWI) is a multisymptom disorder including widespread chronic pain, fatigue and gastrointestinal problems. The objective of this study was to examine the low glutamate diet as a treatment for GWI. Forty veterans with GWI were recruited from across the US. Outcomes included symptom score, myalgic score, tender point count, dolorimetry and the Chalder Fatigue Scale. Subjects were randomized to the low glutamate diet or a wait-listed control group, with symptom score being compared after one month. Subjects then went onto a double-blind, placebo-controlled crossover challenge with monosodium glutamate (MSG)/placebo to test for return of symptoms. Symptom score was compared between diet intervention and wait-listed controls with an independent t-test and effect size was calculated with Cohen’s d. Change scores were analyzed with Wilcoxon Signed Rank tests. Crossover challenge results were analyzed with General Linear Models and cluster analysis. The diet intervention group reported significantly less symptoms (p = 0.0009) than wait-listed controls, with a very large effect size, d = 1.16. Significant improvements in average dolorimetry (p = 0.0006), symptom score, tender point number, myalgic score and the Chalder Fatigue Scale (all p < 0.0001) were observed after the 1-month diet. Challenge with MSG/placebo resulted in significant variability in individual response. These results suggest that the low glutamate diet can effectively reduce overall symptoms, pain and fatigue in GWI, but differential results upon challenge suggest that other aspects of the diet, or underlying differences within the population, may be driving these changes. Future research is needed to identify potential nutrient effects, biomarkers, and underlying metabolic differences between responders and non-responders.
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Quantitative T 2 MRI is predictive of neurodegeneration following organophosphate exposure in a rat model. Sci Rep 2020; 10:13007. [PMID: 32747689 PMCID: PMC7400670 DOI: 10.1038/s41598-020-69991-z] [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: 12/10/2019] [Accepted: 07/13/2020] [Indexed: 02/03/2023] Open
Abstract
Organophosphorus compounds, such as chemical warfare nerve agents and pesticides, are known to cause neurological damage. This study measured nerve agent-related neuropathology and determined whether quantitative T2 MRI could be used as a biomarker of neurodegeneration. Quantitative T2 MRI was performed using a 9.4 T MRI on rats prior to and following soman exposure. T2 images were taken at least 24 h prior, 1 h and 18-24 h after soman exposure. Rats were pre- and post-treated with HI-6 dimethanesulfonate and atropine methyl nitrate. A multicomponent T2 acquisition and analysis was performed. Brains were stained with Fluoro-Jade C to assess neurodegeneration. Rats exposed to soman developed behavioral expression of electrographic seizures. At 18-24 h after soman exposure, significant increases in T2, a possible marker of edema, were found in multiple regions. The largest changes were in the piriform cortex (before: 47.7 ± 1.4 ms; 18-24 h: 82.3 ± 13.4 ms). Fluoro-Jade C staining showed significant neurodegeneration 18-24 h post exposure. The piriform cortex had the strongest correlation between the change in relaxation rate and percent neurodegeneration (r = 0.96, p < 0.001). These findings indicate there is regionally specific neurodegeneration 24 h after exposure to soman. The high correlation between T2 relaxivity and histopathology supports the use of T2 as a marker of injury.
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Zhou R, Yang X, Li X, Qu Y, Huang Q, Sun X, Mu D. Recombinant CC16 inhibits NLRP3/caspase-1-induced pyroptosis through p38 MAPK and ERK signaling pathways in the brain of a neonatal rat model with sepsis. J Neuroinflammation 2019; 16:239. [PMID: 31775794 PMCID: PMC6882041 DOI: 10.1186/s12974-019-1651-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 11/19/2019] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Sepsis is a critical disease associated with extremely high mortality. Some severe forms of sepsis can induce brain injury, thus causing behavioral and cognitive dysfunction. Pyroptosis is a type of cell death that differs from apoptosis and plays an important role in the occurrence and development of infectious diseases, nervous system-related diseases. A recent study has found that there is pyroptosis in the hippocampus of sepsis-induced brain injury, but its mechanism and treatment scheme have not been evaluated. METHODS We established immediately a septic rat model by cecal ligation and perforation (CLP) after administration with recombinant club cell protein (rCC16) and/or U46619 in different groups. The clinical performance, survival percentage, vital signs, and neurobehavioral scores were monitored at different time points. Cortical pathological changes were also examined. The expression of cortical nucleotide-binding domain leucine-rich repeat-containing pyrin domain-containing 3 (NLRP3), caspase-1, (p)-p38 mitogen-activated protein kinase (MAPK), and (p)-extracellular signal-related kinase (ERK) was detected by western blotting and immunofluorescence analysis. The levels of interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha in the cortical supernatant were detected by enzyme-linked immunosorbent assay. RESULTS Compared with the sham group, the clinical performance, survival percentage, vital signs, and severe cortical pathological changes in the CLP group were worse; NLRP3, caspase-1, and inflammatory factor levels were increased; and phosphorylation of p38 MAPK and ERK was also increased. Meanwhile, multiple indicators were deteriorated further after administration of U46619 in CLP rats. The clinical performance of CLP rats, however, was better after rCC16 administration; cortical pathological changes were attenuated; and NLRP3, caspase-1, and inflammatory factor levels and the phosphorylation of signaling pathway proteins (p38 MAPK and ERK) were reduced. Interestingly, the CLP rats showed the opposite changes in all indicators after administration with both rCC16 and U46619 when compared with those administered rCC16 alone. CONCLUSIONS In sepsis, rCC16 inhibits cortical pyroptosis through p38 MAPK and ERK signaling pathways. Meanwhile, rCC16 has a protective effect on newborn rats with sepsis, but it is not clear whether its mechanism is directly related to pyroptosis.
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Affiliation(s)
- Ruixi Zhou
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, China.
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, 610041, China.
| | - Xiaoyan Yang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, 610041, China
| | - Xihong Li
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, China.
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, 610041, China.
| | - Yi Qu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, 610041, China
| | - Qun Huang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, 610041, China
| | - Xuemei Sun
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, 610041, China
| | - Dezhi Mu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, 610041, China
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15
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Hulse EJ, Haslam JD, Emmett SR, Woolley T. Organophosphorus nerve agent poisoning: managing the poisoned patient. Br J Anaesth 2019; 123:457-463. [PMID: 31248646 DOI: 10.1016/j.bja.2019.04.061] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 03/29/2019] [Accepted: 04/05/2019] [Indexed: 10/26/2022] Open
Abstract
Organophosphorus (OP) nerve agent poisoning made the headlines in 2018 with the nerve agent 'Novichok' poisonings in Salisbury, England. This event highlighted a gap in the knowledge of most clinicians in the UK. In response, this special article aims to enlighten and signpost anaesthetists and intensivists towards the general management of OP nerve agent poisoned patients. Drawing on a broad range of sources, we will discuss what OP nerve agents are, how they work, and how to recognise and treat OP nerve agent poisoning. OP nerve agents primarily act by inhibiting the enzyme acetylcholinesterase, causing an acute cholinergic crisis; death usually occurs through respiratory failure. The antimuscarinic agent atropine, oximes (to reactivate acetylcholinesterase), neuroprotective drugs, and critical care remain the mainstays of treatment. The risk to medical staff from OP poisoned patients appears low, especially if there is a thorough decontamination of the poisoned patient and staff wear appropriate personal protective equipment. The events in Salisbury in the past year were shocking, and the staff at Salisbury District General Hospital performed admirably in treating those affected by Novichok nerve agent poisoning. We eagerly anticipate their future clinical publications so that the medical community might learn from their valuable experiences.
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Affiliation(s)
- Elspeth J Hulse
- Institute of Cellular Medicine, Newcastle University, Newcastle Upon Tyne, UK; Academic Department of Military Anaesthesia and Critical Care, RCDM, Birmingham, UK.
| | - James D Haslam
- Anaesthesia and Intensive Care Medicine, Salisbury NHS Foundation Trust, Salisbury, UK
| | | | - Tom Woolley
- Academic Department of Military Anaesthesia and Critical Care, RCDM, Birmingham, UK
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16
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Babele P, Verma S, Kumar RB, Bhagyawant SS, Kamboj DV, Alam SI. Elucidation of protein biomarkers in plasma and urine for epsilon toxin exposure in mouse model. Anaerobe 2019; 59:76-91. [PMID: 31145997 DOI: 10.1016/j.anaerobe.2019.05.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/02/2019] [Accepted: 05/22/2019] [Indexed: 01/09/2023]
Abstract
Epsilon toxin (ETX) is the major virulence determinant of C. perfringens type B or type D strains, causing diseases in animals, besides being a listed biological and toxin warfare (BTW) agent. Keeping in mind the high lethality and the rapid onset of clinical manifestations, early diagnosis of epsilon toxin exposure is of paramount importance for implementation of appropriate medical countermeasures. Using a 2DE-MS approach, the present study is the first comprehensive proteomic elucidation of ETX-induced protein markers in the mouse model, providing putative targets for early diagnosis of ETX exposure. A total of 52 unique proteins showing ETX-induced modulations were identified in plasma and urine samples. Fibrinogen, apolipoprotein, serum amyloid protein, plasminogen, serum albumin, glutathione peroxidase, transferrin, major urinary protein 2, haptoglobin, transthyretin, and vitamin D-binding protein were among the proteins observed in more than one dataset with altered abundance after the ETX-intoxication. The predicted localization, function, and interaction of the ETX-modulated proteins in the plasma and urine indicated involvement of multiple pathways; extracellular proteins, followed by macromolecular complexes associated with blood coagulation and plasminogen activating cascade, being the most prominent among others. The putative markers elucidated here warrants further validation and can be of immense value for the early diagnosis of ETX exposure.
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Affiliation(s)
- Prabhakar Babele
- Biotechnology Division, Defence Research & Development Establishment, Gwalior, 474002, India
| | - Smarti Verma
- Biotechnology Division, Defence Research & Development Establishment, Gwalior, 474002, India
| | - Ravi Bhushan Kumar
- Biotechnology Division, Defence Research & Development Establishment, Gwalior, 474002, India
| | | | - Dev Vrat Kamboj
- Biotechnology Division, Defence Research & Development Establishment, Gwalior, 474002, India
| | - Syed Imteyaz Alam
- Biotechnology Division, Defence Research & Development Establishment, Gwalior, 474002, India.
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17
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Atropine counteracts the depressive-like behaviour elicited by acute exposure to commercial chlorpyrifos in rats. Neurotoxicol Teratol 2019; 71:6-15. [DOI: 10.1016/j.ntt.2018.11.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 11/07/2018] [Accepted: 11/13/2018] [Indexed: 12/30/2022]
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18
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Chaubey K, Alam SI, Waghmare CK, Singh L, Srivastava N, Bhattacharya BK. Differential proteome analysis of rat plasma after diisopropyl fluorophosphate (DFP) intoxication, a surrogate of nerve agent sarin. Chem Biol Interact 2018; 298:66-71. [PMID: 30389396 DOI: 10.1016/j.cbi.2018.10.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 10/22/2018] [Accepted: 10/26/2018] [Indexed: 01/06/2023]
Abstract
Diisopropyl fluorophosphate (DFP), a surrogate of nerve agent sarin, is an organophosphorus (OP) compound which inhibits neuronal enzyme acetylcholinesterase (AChE). Exposure of this compound leads to a wide range of toxic symptoms and survivors may exhibit long term neurotoxicity related to cognitive and memory defects. Due to ease of availability and similar mechanism of action to other highly toxic nerve agent, DFP is widely used as model compound to trace changes associated with nerve agent exposures. Proximal fluids are widely used for the elucidation of biomarkers for exposure to toxic substances and to study the mechanism of toxicity. Using a rat model of OP intoxication, the present study was carried out to elucidate proteomic changes in plasma associated with DFP intoxication. Rats were exposed to a single dose (0.5 LD50) of DFP and their plasma proteome was studied, one day post exposure by two dimensional gel electrophoresis - mass spectrometry (2DE-MS). Some of the milestone changes were validated by Western blot analysis. A total 15 proteins showed significant fold changes in expression with respect to control after 1 day of DFP intoxication. Most of the proteins showing changes in expression at initial stages were related to immunogenic function, acute phase response, blood coagulation, and stress response. Experiments reported here demonstrate that 0.5 LD50 DFP intoxication leads to AChE inhibition, modulation of immunogenic function, and generation of stress at an early stage. Although, some proteins and their putative functional ramifications indicated similarity with those observed in our previous plasma proteome study, neurodegenerative changes were not observed in plasma of 0.5 LD50 DFP treated animals.
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Affiliation(s)
- Kalyani Chaubey
- Defence Research & Development Establishment (DRDE), Jhansi Road, Gwalior, MP, 474002, India
| | - Syed Imteyaz Alam
- Defence Research & Development Establishment (DRDE), Jhansi Road, Gwalior, MP, 474002, India.
| | - Chandra Kant Waghmare
- Defence Research & Development Establishment (DRDE), Jhansi Road, Gwalior, MP, 474002, India
| | - Lokendra Singh
- Defence Research & Development Establishment (DRDE), Jhansi Road, Gwalior, MP, 474002, India
| | - Nalini Srivastava
- School of Studies in Biochemistry, Jiwaji University, Gwalior, MP, 474002, India
| | - Bijoy K Bhattacharya
- Defence Research & Development Establishment (DRDE), Jhansi Road, Gwalior, MP, 474002, India.
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19
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Ravid O, Elhaik Goldman S, Macheto D, Bresler Y, De Oliveira RI, Liraz-Zaltsman S, Gosselet F, Dehouck L, Beeri MS, Cooper I. Blood-Brain Barrier Cellular Responses Toward Organophosphates: Natural Compensatory Processes and Exogenous Interventions to Rescue Barrier Properties. Front Cell Neurosci 2018; 12:359. [PMID: 30459557 PMCID: PMC6232705 DOI: 10.3389/fncel.2018.00359] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 09/24/2018] [Indexed: 11/13/2022] Open
Abstract
Organophosphorus compounds (OPs) are highly toxic chemicals widely used as pesticides (e.g., paraoxon (PX)- the active metabolite of the insecticide parathion) and as chemical warfare nerve agents. Blood-brain barrier (BBB) leakage has been shown in rodents exposed to PX, which is an organophosphate oxon. In this study, we investigated the cellular mechanisms involved in BBB reaction after acute exposure to PX in an established in vitro BBB system made of stem-cell derived, human brain-like endothelial cells (BLECs) together with brain pericytes that closely mimic the in vivo BBB. Our results show that PX directly affects the BBB in vitro both at toxic and non-toxic concentrations by attenuating tight junctional (TJ) protein expression and that only above a certain threshold the paracellular barrier integrity is compromised. Below this threshold, BLECs exhibit a morphological coping mechanism in which they enlarge their cell area thus preventing the formation of meaningful intercellular gaps and maintaining barrier integrity. Importantly, we demonstrate that reversal of the apoptotic cell death induced by PX, by a pan-caspase-inhibitor ZVAD-FMK (ZVAD) can reduce PX-induced cell death and elevate cell area but do not prevent the induced BBB permeability, implying that TJ complex functionality is hindered. This is corroborated by formation of ROS at all toxic concentrations of PX and which are even higher with ZVAD. We suggest that while lower levels of ROS can induce compensating mechanisms, higher PX-induced oxidative stress levels interfere with barrier integrity.
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Affiliation(s)
- Orly Ravid
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - Shirin Elhaik Goldman
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - David Macheto
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - Yael Bresler
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | | | - Sigal Liraz-Zaltsman
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - Fabien Gosselet
- Blood-Brain Barrier Laboratory (LBHE), Université d'Artois, Lens, France
| | - Lucie Dehouck
- Blood-Brain Barrier Laboratory (LBHE), Université d'Artois, Lens, France
| | - Michal Schnaider Beeri
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel.,Interdisciplinary Center Herzliya, Herzliya, Israel.,Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Itzik Cooper
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel.,Interdisciplinary Center Herzliya, Herzliya, Israel
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20
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Bajgar J. Complex View on Poisoning with Nerve Agents and Organophosphates. ACTA MEDICA (HRADEC KRÁLOVÉ) 2018. [DOI: 10.14712/18059694.2018.23] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
OP/nerve agents are still considered as important chemicals acting on living organisms and widely used in human practice. Nerve agents are the most lethal chemical warfare agents. They are characterized according to their action as compounds influencing cholinergic nerve transmission via inhibition of AChE. The symptoms of intoxication comprise nicotinic, muscarinic and central symptoms, for some OP/nerve agents, a delayed neurotoxicity is observed. Cholinesterases (AChE and BuChE) are characterized as the main enzymes involved in the toxic effect of these compounds including their molecular forms. The activity of both enzymes (and molecular forms) is influenced by inhibitors and other factors such as pathological states. There are different methods for cholinesterase determination, however, the most frequent is the method based on the hydrolysis of thiocholine esters and following detection of free SH-group of the released thiocholine. The diagnosis of OP/nerve agents poisoning is based on anamnesis, the clinical status of the intoxicated organism and on cholinesterase determination in the blood. Some principles of prophylaxis against OP/nerve agents poisoning comprising the administration of reversible cholinesterase inhibitors such as pyridostigmine (alone or in combination with other drugs), scavengers such as preparations of cholinesterases, some therapeutic drugs and possible combinations are given. Basic principles of the treatment of nerve agents/OP poisoning are described. New drugs for the treatment are under experimental study based on new approaches to the mechanism of action.
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21
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Olivares-Bañuelos TN, Martínez-Hernández I, Hernández-Kelly LC, Chi-Castañeda D, Vega L, Ortega A. The neurotoxin diethyl dithiophosphate impairs glutamate transport in cultured Bergmann glia cells. Neurochem Int 2018; 123:77-84. [PMID: 29908254 DOI: 10.1016/j.neuint.2018.06.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/29/2018] [Accepted: 06/10/2018] [Indexed: 12/24/2022]
Abstract
Glutamate, the main excitatory neurotransmitter in the vertebrate Central Nervous System, is involved in almost every aspect of brain physiology, and its signaling properties are severely affected in most neurodegenerative diseases. This neurotransmitter has to be efficiently removed from the synaptic cleft in order to prevent an over-stimulation of glutamate receptors that leads to neuronal death. Specific sodium-dependent membrane transporters, highly enriched in glial cells, elicit the clearance of glutamate. Once internalized, it is metabolized to glutamine by the glia-enriched enzyme Glutamine synthetase. Accumulated glutamine is released into the extracellular space for its uptake into pre-synaptic neurons and its conversion to glutamate that is packed into synaptic vesicles completing the glutamate/glutamine cycle. Diverse chemical compounds, like organophosphates, directly affect brain chemistry by altering levels of neurotransmitters in the synaptic cleft. Organophosphate compounds are widely used as pesticides, and all living organisms are continuously exposed to these substances, either in a direct or indirect manner. Its metabolites, like the diethyl dithiophosphate, are capable of causing brain damage through diverse mechanisms including perturbation of neuronal-glial cell interactions and have been associated with attention-deficit disorders and other mental illness. In order to characterize the neurotoxic mechanisms of diethyl dithiophosphate, we took advantage of the well characterized model of chick cerebellar Bergmann glia cultures. A significant impairment of [3H] d-Aspartate transport was found upon exposure to the metabolite. These results indicate that glia cells are targets of neurotoxic substances such as pesticides and that these cells might be critically involved in the associated neuronal death.
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Affiliation(s)
- Tatiana N Olivares-Bañuelos
- Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Ensenada, 22860, Mexico
| | - Isabel Martínez-Hernández
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados Del Instituto Politécnico Nacional, Ciudad de México, 07000, Mexico
| | - Luisa C Hernández-Kelly
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados Del Instituto Politécnico Nacional, Ciudad de México, 07000, Mexico
| | - Donají Chi-Castañeda
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados Del Instituto Politécnico Nacional, Ciudad de México, 07000, Mexico; Soluciones para un México Verde S.A. de C.V, Ciudad de México, 01210, Mexico
| | - Libia Vega
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados Del Instituto Politécnico Nacional, Ciudad de México, 07000, Mexico
| | - Arturo Ortega
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados Del Instituto Politécnico Nacional, Ciudad de México, 07000, Mexico.
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Sex modulated effects of sarin exposure in rats: Toxicity, hypothermia and inflammatory markers. Neurotoxicology 2018; 66:121-127. [DOI: 10.1016/j.neuro.2018.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 03/28/2018] [Accepted: 04/02/2018] [Indexed: 12/31/2022]
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23
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Assessment of brain oxygenation imbalance following soman exposure in rats. Neurotoxicology 2018; 65:28-37. [PMID: 29378300 DOI: 10.1016/j.neuro.2018.01.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 01/18/2018] [Accepted: 01/19/2018] [Indexed: 10/18/2022]
Abstract
Nerve agents (NAs) are potent organophosphorus (OP) compounds with applications in chemical warfare. OP compounds act by inhibiting acetylcholinesterase (AChE). Soman (O-pinacolyl methylphosphonofluoridate) is one of the most potent NAs. It is well known that small doses of NAs can be lethal, and that even non-lethal exposure leads to long-term mental debilitation/neurological damage. However, the neuropathology following exposure to sub-lethal nerve agents is not well understood. In this study, we examined changes in tissue oxygenation (pO2) in the cortex and hippocampus after a sub-lethal dose of soman [80-90 μg/kg; subcutaneous]. pO2 changes can provide information regarding oxygen delivery and utilization and may be indicative of a disruption in cerebral blood flow and/or metabolism. Changes in oxygenation were measured with chronically implanted oxygen sensors in awake and freely moving rats. Measurements were taken before, during, and after soman-induced convulsive seizures. Soman exposure resulted in an immediate increase in pO2 in the cortex, followed by an even greater increase that precedes the onset of soman-induced convulsive seizures. The rise in hippocampus pO2 was delayed relative to the cortex, although the general pattern of brain oxygenation between these two regions was similar. After convulsive seizures began, pO2 levels declined but usually remained hyperoxygenated. Following the decline in pO2, low frequency cycles of large amplitude changes were observed in both the cortex and hippocampus. This pattern is consistent with recurring seizures. Measuring real-time changes in brain pO2 provides new information on the physiological status of the brain following soman exposure. These results highlight that the measurement of brain oxygenation could provide a sensitive marker of nerve agent exposure and serve as a biomarker for treatment studies.
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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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25
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Evidence of Hippocampal Structural Alterations in Gulf War Veterans With Predicted Exposure to the Khamisiyah Plume. J Occup Environ Med 2017; 59:923-929. [DOI: 10.1097/jom.0000000000001082] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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26
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El Rahman HAA, Salama M, Gad El-Hak SA, El-Harouny MA, ElKafrawy P, Abou-Donia MB. A Panel of Autoantibodies Against Neural Proteins as Peripheral Biomarker for Pesticide-Induced Neurotoxicity. Neurotox Res 2017; 33:316-336. [PMID: 28875469 DOI: 10.1007/s12640-017-9793-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 07/21/2017] [Accepted: 08/03/2017] [Indexed: 12/16/2022]
Abstract
In the present study, we screened the sera of subjects chronically exposed to mixtures of pesticides (composed mainly of organophosphorus compounds (OPs) and others) and developed neurological symptoms for the presence of autoantibodies against cytoskeletal neural proteins. OPs have a well-characterized clinical profile resulting from acute cholinergic crisis. However, some of these compounds cause neuronal degeneration and demyelination known as organophosphorus compound-induced delayed neurotoxicity (OPIDN) and/or organophosphorus compound-induced chronic neurotoxicity (OPICN). Studies from our group have demonstrated the presence of autoantibodies to essential neuronal and glial proteins against cytoskeletal neural proteins in patients with chemical-induced brain injury. In this study, we screened the serum of 50 pesticide-exposed subjects and 25 non-exposed controls, using Western blot analysis against the following proteins: neurofilament triplet proteins (NFPs), tubulin, microtubule-associated tau proteins (Tau), microtubule-associated protein-2 (MAP-2), myelin basic protein (MBP), myelin-associated glycoprotein (MAG), glial fibrillary acidic protein (GFAP), calcium-calmodulin kinase II (CaMKII), glial S100-B protein, and alpha-synuclein (SNCA). Serum reactivity was measured as arbitrary chemiluminescence units. As a group, exposed subjects had significantly higher levels of autoantibody reactivity in all cases examined. The folds of increase in of autoantibodies against neural proteins of the subjects compared to healthy humans in descending order were as follows: MBP, 7.67, MAG 5.89, CaMKII 5.50, GFAP 5.1, TAU 4.96, MAP2 4.83, SNCA 4.55, NFP 4.55, S-100B 2.43, and tubulin 1.78. This study has demonstrated the presence of serum autoantibodies to central nervous system-specific proteins in a group of farmers chronically exposed to pesticides who developed neurological signs and symptoms of neural injury. These autoantibodies can be used as future diagnostic/therapeutic target for OP-induced neurotoxicity.
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Affiliation(s)
- Heba Allah Abd El Rahman
- Department of Forensic Medicine and Clinical Toxicology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Mohamed Salama
- Department of Forensic Medicine and Clinical Toxicology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Seham A Gad El-Hak
- Department of Forensic Medicine and Clinical Toxicology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Mona A El-Harouny
- Department of Forensic Medicine and Clinical Toxicology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | | | - Mohamed B Abou-Donia
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina, 27710, USA.
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Screening for novel central nervous system biomarkers in veterans with Gulf War Illness. Neurotoxicol Teratol 2017; 61:36-46. [DOI: 10.1016/j.ntt.2017.03.002] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 03/02/2017] [Accepted: 03/03/2017] [Indexed: 12/19/2022]
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28
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Merwin SJ, Obis T, Nunez Y, Re DB. Organophosphate neurotoxicity to the voluntary motor system on the trail of environment-caused amyotrophic lateral sclerosis: the known, the misknown, and the unknown. Arch Toxicol 2017; 91:2939-2952. [PMID: 28070599 DOI: 10.1007/s00204-016-1926-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 12/20/2016] [Indexed: 12/12/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is the most common adult-onset paralytic disorder. It is characterized by progressive degeneration of the motor neurons controlling voluntary movement. The underlying mechanisms remain elusive, a fact that has precluded development of effective treatments. ALS presents as a sporadic condition 90-95% of the time, i.e., without familial history or obvious genetic mutation. This suggests that ALS has a strong environmental component. Organophosphates (OPs) are prime candidate neurotoxicants in the etiology of ALS, as exposure to OPs was linked to higher ALS incidence among farmers, soccer players, and Gulf War veterans. In addition, polymorphisms in paraoxonase 1, an enzyme that detoxifies OPs, may increase individual vulnerability both to OP poisoning and to the risk of developing ALS. Furthermore, exposure to high doses of OPs can give rise to OP-induced delayed neuropathy (OPIDN), a debilitating condition akin to ALS characterized by similar motor impairment and paralysis. The question we pose in this review is: "what can we learn from acute exposure to high doses of neurotoxicants (OPIDN) that could help our understanding of chronic diseases resulting from potentially decades of silent exposure (ALS)?" The resemblances between OPIDN and ALS are striking at the clinical, etiological, neuropathological, cellular, and potentially molecular levels. Here, we critically present available evidence, discuss current limitations, and posit future research. In the search for the environmental origin of ALS, OPIDN offers an exciting trail to follow, which can hopefully lead to the development of novel strategies to prevent and cure these dreadful disorders.
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Affiliation(s)
- Samantha J Merwin
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, 10032, USA.,NIEHS Center for Environmental Health Sciences in Northern Manhattan, Columbia University, New York, NY, 10032, USA.,Center for Motor Neuron Biology and Disease, Columbia University, New York, NY, 10032, USA
| | - Teresa Obis
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, 10032, USA.,NIEHS Center for Environmental Health Sciences in Northern Manhattan, Columbia University, New York, NY, 10032, USA.,Center for Motor Neuron Biology and Disease, Columbia University, New York, NY, 10032, USA
| | - Yanelli Nunez
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, 10032, USA.,NIEHS Center for Environmental Health Sciences in Northern Manhattan, Columbia University, New York, NY, 10032, USA.,Center for Motor Neuron Biology and Disease, Columbia University, New York, NY, 10032, USA.,Toxicology Ph.D. Program, Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, 10032, USA
| | - Diane B Re
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, 10032, USA. .,NIEHS Center for Environmental Health Sciences in Northern Manhattan, Columbia University, New York, NY, 10032, USA. .,Center for Motor Neuron Biology and Disease, Columbia University, New York, NY, 10032, USA. .,, 722 W 168th street Suite 1107B, New York, NY, 10032, USA.
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Abou-Donia MB, Siracuse B, Gupta N, Sobel Sokol A. Sarin (GB, O-isopropyl methylphosphonofluoridate) neurotoxicity: critical review. Crit Rev Toxicol 2016; 46:845-875. [PMID: 27705071 PMCID: PMC5764759 DOI: 10.1080/10408444.2016.1220916] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Sarin (GB, O-isopropyl methylphosphonofluoridate) is a potent organophosphorus (OP) nerve agent that inhibits acetylcholinesterase (AChE) irreversibly. The subsequent build-up of acetylcholine (ACh) in the central nervous system (CNS) provokes seizures and, at sufficient doses, centrally-mediated respiratory arrest. Accumulation of ACh at peripheral autonomic synapses leads to peripheral signs of intoxication and overstimulation of the muscarinic and nicotinic receptors, which is described as "cholinergic crisis" (i.e. diarrhea, sweating, salivation, miosis, bronchoconstriction). Exposure to high doses of sarin can result in tremors, seizures, and hypothermia. More seriously, build-up of ACh at neuromuscular junctions also can cause paralysis and ultimately peripherally-mediated respiratory arrest which can lead to death via respiratory failure. In addition to its primary action on the cholinergic system, sarin possesses other indirect effects. These involve the activation of several neurotransmitters including gamma-amino-butyric acid (GABA) and the alteration of other signaling systems such as ion channels, cell adhesion molecules, and inflammatory regulators. Sarin exposure is associated with symptoms of organophosphate-induced delayed neurotoxicity (OPIDN) and organophosphate-induced chronic neurotoxicity (OPICN). Moreover, sarin has been involved in toxic and immunotoxic effects as well as organophosphate-induced endocrine disruption (OPIED). The standard treatment for sarin-like nerve agent exposure is post-exposure injection of atropine, a muscarinic receptor antagonist, accompanied by an oxime, an AChE reactivator, and diazepam.
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Affiliation(s)
- Mohamed B Abou-Donia
- a Department of Pharmacology and Cancer Biology , Duke University , Durham , NC , USA
| | - Briana Siracuse
- a Department of Pharmacology and Cancer Biology , Duke University , Durham , NC , USA
| | - Natasha Gupta
- a Department of Pharmacology and Cancer Biology , Duke University , Durham , NC , USA
| | - Ashly Sobel Sokol
- a Department of Pharmacology and Cancer Biology , Duke University , Durham , NC , USA
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30
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Eisenkraft A, Falk A. Possible role for anisodamine in organophosphate poisoning. Br J Pharmacol 2016; 173:1719-27. [PMID: 27010563 DOI: 10.1111/bph.13486] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 03/02/2016] [Accepted: 03/17/2016] [Indexed: 12/16/2022] Open
Abstract
In cases of organophosphate poisoning, patients are treated with a combination of antidotes. In addition to these poison-directed antidotes, patients may require extra oxygen and artificial ventilation; other modalities may also be needed due to the wide range of toxic effects. Anisodamine is a belladonna alkaloid, and like other drugs from this family is non subtype-selective muscarinic, and a nicotinic cholinoceptor antagonist, which has been employed in traditional Chinese medicine. As a muscarinic antagonist, it displays similar pharmacological effects to atropine and scopolamine. However, anisodamine is not only less potent than atropine and scopolamine but also less toxic. Current in vitro and animal model studies have demonstrated that anisodamine has protective effects in a variety of diseases. Organophosphate poisoning involves not only the central and peripheral nervous systems, but also the cardiac and respiratory systems, as well as activation of inflammatory processes and oxidative stress. Therefore, the anticholinergic and additional activities of anisodamine appear to be relevant and justify its consideration as an addition to the existing remedies. However, more research is needed, as at present data on the role of anisodamine in the management of organophosphate poisoning are limited. Here, we review the beneficial effects of anisodamine on processes relevant to organophosphate poisoning.
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Affiliation(s)
- Arik Eisenkraft
- Israel Ministry of Defense, HaKirya, Tel Aviv, Israel.,Israel Defense Force Medical Corps, Ramat Gan, Israel.,The Institute for Research in Military Medicine, The Faculty of Medicine, The Hebrew University, Jerusalem, Israel
| | - Avshalom Falk
- Israel Ministry of Defense, HaKirya, Tel Aviv, Israel
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Early Loss of Blood-Brain Barrier Integrity Precedes NOX2 Elevation in the Prefrontal Cortex of an Animal Model of Psychosis. Mol Neurobiol 2016; 54:2031-2044. [PMID: 26910819 PMCID: PMC5355521 DOI: 10.1007/s12035-016-9791-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 02/11/2016] [Indexed: 12/29/2022]
Abstract
The social isolation rearing of young adult rats is a model of psychosocial stress and provides a nonpharmacological tool to study alterations reminiscent of symptoms seen in psychosis. We have previously demonstrated that social isolation in rats leads to increased oxidative stress and to cerebral NOX2 elevations. Here, we investigated early alterations in mRNA expression leading to increased NOX2 in the brain. Rats were exposed to a short period of social isolation (1 week) and real-time polymerase chain reaction (PCR) for mRNA expression of genes involved in blood-brain barrier (BBB) formation and integrity (ORLs, Vof 21 and Vof 16, Leng8, Vnr1, and Trank 1 genes) was performed. Real-time PCR experiments, immunohistochemistry, and Western blotting analysis showed an increased expression of these genes and related proteins in isolated rats with respect to control animals. The expression of specific markers of BBB integrity, such as matrix metalloproteinase 2 (MMP2), matrix metalloproteinase 9 (MMP9), occludin 1, and plasmalemmal vesicle associated protein-1 (PV-1), was also significantly altered after 1 week of social isolation. BBB permeability, evaluated by quantification of Evans blue dye extravasation, as well as interstitial fluid, was significantly increased in rats isolated for 1 week with respect to controls. Isolation-induced BBB disruption was also accompanied by a significant increase of Interleukin 6 (IL-6) expression. Conversely, no differences in NOX2 levels were detected at this time point. Our study demonstrates that BBB disruption precedes NOX2 elevations in the brain. These results provide new insights in the interplay of mechanisms linking psychosocial stress to early oxidative stress in the brain, disruption of the BBB, and the development of mental disorders.
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32
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Golier JA, Caramanica K, Michaelides AC, Makotkine I, Schmeidler J, Harvey PD, Yehuda R. A randomized, double-blind, placebo-controlled, crossover trial of mifepristone in Gulf War veterans with chronic multisymptom illness. Psychoneuroendocrinology 2016; 64:22-30. [PMID: 26600007 DOI: 10.1016/j.psyneuen.2015.11.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 11/03/2015] [Accepted: 11/03/2015] [Indexed: 01/21/2023]
Abstract
No pharmacological treatments have been demonstrated to effectively treat chronic multisymptom illness (CMI) in Gulf War veterans (GWV). This study assessed the effect of the glucocorticoid receptor antagonist mifepristone in GWV with CMI. A randomized, double-blind, cross-over trial of mifepristone, with two six-week treatment phases separated by a one-month washout period, was conducted at a Veterans Affairs (VA) hospital between 2008 and 2011. Participants were randomized to receive either 200mg of mifepristone per day or matched placebo first. The primary clinical outcome measure was change in self-reported physical health. Neurocognitive functioning and self-reported measures of depression, PTSD, and fatigue were secondary outcomes. Sixty-five participants enrolled, of whom 36 were randomized and 32 (mean age, 49.1 (7.2) years) completed the study. Physical and mental health status and neurocognitive functioning were poor at baseline. Mifepristone treatment was not associated with improvement in self-reported physical health (p=0.838) or in other self-reported measures of mental health. Mifepristone treatment was significantly associated with improvements in verbal learning (p=0.008, d=0.508), in the absence of improvement in other cognitive measures (working memory (p=0.914), visual learning (p=0.643) and a global composite measure (p=0.937). Baseline morning cortisol levels and lysozyme IC50-DEX, a measure of peripheral glucocorticoid sensitivity, displayed a significant relationship with endpoint verbal learning scores (p=0.012 and p=0.007, respectively). The magnitude of cortisol change during treatment mediated the improvement in verbal learning. This study was negative for the primary and secondary clinical outcomes. However, the data suggest a moderate dose of mifepristone may have circumscribed cognitive-enhancing effects in CMI. Further study is warranted to determine whether and through which mechanisms mifepristone treatment can yield clinically meaningful improvement in cognitive function in CMI or other neuropsychiatric conditions associated with HPA axis dysregulation.
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Affiliation(s)
- Julia A Golier
- James J. Peters VA Medical Center, OOMH-526, 130 West Kingsbridge Road, Bronx, NY 10468, United States; Psychiatry Department, Icahn School of Medicine at Mount Sinai, 1428 Madison Ave, New York, NY 10029, United States.
| | - Kimberly Caramanica
- James J. Peters VA Medical Center, OOMH-526, 130 West Kingsbridge Road, Bronx, NY 10468, United States
| | - Andreas C Michaelides
- James J. Peters VA Medical Center, OOMH-526, 130 West Kingsbridge Road, Bronx, NY 10468, United States
| | - Iouri Makotkine
- James J. Peters VA Medical Center, OOMH-526, 130 West Kingsbridge Road, Bronx, NY 10468, United States; Psychiatry Department, Icahn School of Medicine at Mount Sinai, 1428 Madison Ave, New York, NY 10029, United States
| | - James Schmeidler
- Psychiatry Department, Icahn School of Medicine at Mount Sinai, 1428 Madison Ave, New York, NY 10029, United States
| | - Philip D Harvey
- Miller School of Medicine, University of Miami, 1600 NW 10th Ave #1140, Miami, FL 33136, United States
| | - Rachel Yehuda
- James J. Peters VA Medical Center, OOMH-526, 130 West Kingsbridge Road, Bronx, NY 10468, United States; Psychiatry Department, Icahn School of Medicine at Mount Sinai, 1428 Madison Ave, New York, NY 10029, United States
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33
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Chaubey K, Rao MK, Alam SI, Waghmare C, Bhattacharya BK. Increased expression of immune modulator proteins and decreased expression of apolipoprotein A-1 and haptoglobin in blood plasma of sarin exposed rats. Chem Biol Interact 2016; 246:36-44. [DOI: 10.1016/j.cbi.2016.01.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Revised: 01/06/2016] [Accepted: 01/07/2016] [Indexed: 12/28/2022]
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Kaur S, Singh S, Chahal KS, Prakash A. Potential pharmacological strategies for the improved treatment of organophosphate-induced neurotoxicity. Can J Physiol Pharmacol 2014; 92:893-911. [DOI: 10.1139/cjpp-2014-0113] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Organophosphates (OP) are highly toxic compounds that cause cholinergic neuronal excitotoxicity and dysfunction by irreversible inhibition of acetylcholinesterase, resulting in delayed brain damage. This delayed secondary neuronal destruction, which arises primarily in the cholinergic areas of the brain that contain dense accumulations of cholinergic neurons and the majority of cholinergic projection, could be largely responsible for persistent profound neuropsychiatric and neurological impairments such as memory, cognitive, mental, emotional, motor, and sensory deficits in the victims of OP poisoning. The therapeutic strategies for reducing neuronal brain damage must adopt a multifunctional approach to the various steps of brain deterioration: (i) standard treatment with atropine and related anticholinergic compounds; (ii) anti-excitotoxic therapies to prevent cerebral edema, blockage of calcium influx, inhibition of apoptosis, and allow for the control of seizure; (iii) neuroprotection by aid of antioxidants and N-methyl-d-aspartate (NMDA) antagonists (multifunctional drug therapy), to inhibit/limit the secondary neuronal damage; and (iv) therapies targeting chronic neuropsychiatric and neurological symptoms. These neuroprotective strategies may prevent secondary neuronal damage in both early and late stages of OP poisoning, and thus may be a beneficial approach to treating the neuropsychological and neuronal impairments resulting from OP toxicity.
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Affiliation(s)
- Shamsherjit Kaur
- Department of Pharmacology, ISF College of Pharmacy, Moga 142001, Punjab, India
- Punjab Technical University, Kapurthala 144601, Punjab, India
| | - Satinderpal Singh
- Department of Pharmacology, ISF College of Pharmacy, Moga 142001, Punjab, India
| | - Karan Singh Chahal
- Department of Pharmacology, ISF College of Pharmacy, Moga 142001, Punjab, India
| | - Atish Prakash
- Department of Pharmacology, ISF College of Pharmacy, Moga 142001, Punjab, India
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Kalász H, Nurulain SM, Veress G, Antus S, Darvas F, Adeghate E, Adem A, Hashemi F, Tekes K. Mini review on blood-brain barrier penetration of pyridinium aldoximes. J Appl Toxicol 2014; 35:116-23. [PMID: 25291712 DOI: 10.1002/jat.3048] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 06/14/2014] [Accepted: 06/16/2014] [Indexed: 01/27/2023]
Abstract
This paper reviews the blood-brain barrier (BBB) penetration of newly developed pyridinium aldoximes. Pyridinium aldoximes are highly charged hydrophilic compounds used in the treatment of subjects exposed to organophosphonates because they are effective as acetylcholinesterase reactivators. Pyridinium aldoximes have antidotal effects against poisoning with cholinesterase inhibitors, a frequent problem affecting people working with organophosphate-based insecticides and pesticides. Toxic organophosphonate products such as sarin and tabun can be used by terrorists as chemical warfare agents. This poses a severe challenge to all innocent and peace-loving people worldwide. This review gives a brief summary of BBB transporters and description of the current in vitro and in vivo methods for the characterization of BBB penetration of established and novel pyridinium aldoximes. The authors provide a putative mechanism of penetration, outline some future ways of formulation and discuss the possible advantages and disadvantages of increasing BBB penetration.
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Affiliation(s)
- H Kalász
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, 1089, Budapest, Nagyvárad tér 4, Hungary; Department of Pharmacology and Therapeutics, CMHS, United Arab Emirates University, Al Ain, P.O.Box 17666, United Arab Emirates
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Chao LL, Kriger S, Buckley S, Ng P, Mueller SG. Effects of low-level sarin and cyclosarin exposure on hippocampal subfields in Gulf War Veterans. Neurotoxicology 2014; 44:263-9. [PMID: 25058901 PMCID: PMC5464327 DOI: 10.1016/j.neuro.2014.07.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 07/10/2014] [Accepted: 07/11/2014] [Indexed: 11/26/2022]
Abstract
BACKGROUND More than 100,000 US troops were potentially exposed to chemical warfare agents sarin (GB) and cyclosarin (GF) when an ammunition dump at Khamisiyah, Iraq was destroyed during the 1991 Gulf War (GW). We previously reported reduced hippocampal volume in GW veterans with suspected GB/GF exposure relative to matched, unexposed GW veterans estimated from 1.5T magnetic resonance images (MRI). Here we investigate, in a different cohort of GW veterans, whether low-level GB/GF exposure is associated with structural alterations in specific hippocampal subfields, estimated from 4T MRI. METHODS The Automatic Segmentation of Hippocampal Subfields (ASHS) technique was used to quantify CA1, CA2, CA3 and dentate gyrus (DG), and subiculum (SUB) subfields volumes from high-resolution T2-weighted images acquired on a 4T MR scanner in 56 GW veterans with suspected GB/GF exposure and 56 "matched" unexposed GW veterans (mean age 49±7 years). RESULTS GB/GF exposed veterans had smaller CA2 (p=0.003) and CA3/DG (p=0.01) subfield volumes compared to matched, unexposed GW veterans. There were no group difference in total hippocampal volume, quantified with FreeSurfer, and no dose-response relationship between estimated levels of GB/GF exposure and total hippocampal or subfield volume. CONCLUSIONS These findings extend our previous report of structural alterations in the hippocampi of GW veterans with suspected GB/GF exposure to volume changes in the CA2, CA3, and DG hippocampal subfields in a different cohort of GW veterans with suspected GB/GF exposure.
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Affiliation(s)
- Linda L Chao
- Center for Imaging of Neurodegenerative Diseases, San Francisco Veterans Affairs Medical Center, 4150 Clement Street, 114M, San Francisco, CA 94121, United States; Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States; Department of Psychiatry, University of California San Francisco, San Francisco, CA, United States.
| | - Stephen Kriger
- Center for Imaging of Neurodegenerative Diseases, San Francisco Veterans Affairs Medical Center, 4150 Clement Street, 114M, San Francisco, CA 94121, United States
| | - Shannon Buckley
- Center for Imaging of Neurodegenerative Diseases, San Francisco Veterans Affairs Medical Center, 4150 Clement Street, 114M, San Francisco, CA 94121, United States
| | - Peter Ng
- Center for Imaging of Neurodegenerative Diseases, San Francisco Veterans Affairs Medical Center, 4150 Clement Street, 114M, San Francisco, CA 94121, United States
| | - Susanne G Mueller
- Center for Imaging of Neurodegenerative Diseases, San Francisco Veterans Affairs Medical Center, 4150 Clement Street, 114M, San Francisco, CA 94121, United States; Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States
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Misik J, Pavlikova R, Cabal J, Kuca K. Acute toxicity of some nerve agents and pesticides in rats. Drug Chem Toxicol 2014; 38:32-6. [PMID: 24641243 DOI: 10.3109/01480545.2014.900070] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVES Highly toxic organophosphorus compounds (V- and G-nerve agents) were originally synthesized for warfare or as agricultural pesticides. Data on their acute toxicity are rare and patchy. Therefore, there is a need for integrated summary comparing acute toxicity of organophosphates using different administration routes in the same animal model with the same methodology. Based on original data, a summary of in vivo acute toxicity of selected V- and G-nerve agents (tabun, sarin, soman, VX, Russian VX) and organophosphates paraoxon (POX) and diisopropyl fluorophosphate (DFP) in rats has been investigated. MATERIALS AND METHODS Male Wistar rats were exposed to organophosphates in several administration routes (i.m., i.p., p.o, s.c., p.c.). The acute toxicity was evaluated by the assessment of median lethal dose (LD50, mg kg(-1)) 2, 4, and 24 hours post exposure. RESULTS V-agents were the most toxic presented with LD50 ranged from 0.0082 mg kg(-1) (VX, i.m.) to 1.402 mg kg(-1) (Russian VX, p.o.), followed by G-agents (LD50 = 0.069 mg kg(-1)/soman, i.m./ - 117.9 mg kg(-1)/sarin, p.c./), organophosphate POX and DFP (LD50 = 0.321 mg kg(-1)/POX, i.m./ - 420 mg kg(-1)/DFP, p.c./). Generally, i.m. administration was the most toxic throughout all tested agents and ways of administration (LD50 = 0.0082 mg kg(-1)/VX/ - 1.399 mg kg(-1)/DFP/) whereas p.c. way was responsible for lowest acute toxicity (LD50 = 0.085 mg kg(-1)/VX/ - 420 mg kg(-1)/DFP/). CONCLUSION The acute toxicity of selected organophosphorus compounds is summarized throughout this study. Although the data assessed in rats are rather illustrative prediction for human, it presents a valuable contribution, indicating the toxic potential and harmfulness of organophosphates.
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Affiliation(s)
- Jan Misik
- Faculty of Military Health Sciences, University of Defence , Trebesska, Hradec Kralove , Czech Republic and
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Biancardi VC, Son SJ, Ahmadi S, Filosa JA, Stern JE. Circulating angiotensin II gains access to the hypothalamus and brain stem during hypertension via breakdown of the blood-brain barrier. Hypertension 2013; 63:572-9. [PMID: 24343120 DOI: 10.1161/hypertensionaha.113.01743] [Citation(s) in RCA: 182] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Angiotensin II-mediated vascular brain inflammation emerged as a novel pathophysiological mechanism in neurogenic hypertension. However, the precise underlying mechanisms and functional consequences in relation to blood-brain barrier (BBB) integrity and central angiotensin II actions mediating neurohumoral activation in hypertension are poorly understood. Here, we aimed to determine whether BBB permeability within critical hypothalamic and brain stem regions involved in neurohumoral regulation was altered during hypertension. Using digital imaging quantification after intravascularly injected fluorescent dyes and immunohistochemistry, we found increased BBB permeability, along with altered key BBB protein constituents, in spontaneously hypertensive rats within the hypothalamic paraventricular nucleus, the nucleus of the solitary tract, and the rostral ventrolateral medulla, all critical brain regions known to contribute to neurohumoral activation during hypertension. BBB disruption, including increased permeability and downregulation of constituent proteins, was prevented in spontaneously hypertensive rats treated with the AT1 receptor antagonist losartan, but not with hydralazine, a direct vasodilator. Importantly, we found circulating angiotensin II to extravasate into these brain regions, colocalizing with neurons and microglial cells. Taken together, our studies reveal a novel angiotensin II-mediated feed-forward mechanism during hypertension, by which circulating angiotensin II evokes increased BBB permeability, facilitating in turn its access to critical brain regions known to participate in blood pressure regulation.
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Watanabe Y, Itoh T, Shiraishi H, Maeno Y, Arima Y, Torikoshi A, Namera A, Makita R, Yoshizumi M, Nagao M. Acute effects of a sarin-like organophosphorus agent, bis(isopropyl methyl)phosphonate, on cardiovascular parameters in anaesthetized, artificially ventilated rats. Toxicol Appl Pharmacol 2013; 272:61-6. [DOI: 10.1016/j.taap.2013.06.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 05/29/2013] [Accepted: 06/05/2013] [Indexed: 11/30/2022]
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Pita R, Marco-Contelles J, Ramos E, Del Pino J, Romero A. Toxicity induced by chemical warfare agents: insights on the protective role of melatonin. Chem Biol Interact 2013; 206:134-42. [PMID: 24035908 DOI: 10.1016/j.cbi.2013.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Revised: 08/24/2013] [Accepted: 09/02/2013] [Indexed: 02/07/2023]
Abstract
Chemical Warfare Agents (CWAs) are substances that can be used to kill, injure or incapacitate an enemy in warfare, but also against civilian population in terrorist attacks. Many chemical agents are able to generate free radicals and derived reactants, excitotoxicity process, or inflammation, and as consequence they can cause neurological symptoms and damage in different organs. Nowadays, taking into account that total immediate decontamination after exposure is difficult to achieve and there are not completely effective antidotes and treatments against all CWAs, we advance and propose that medical countermeasures against CWAs poisoning would benefit from a broad-spectrum multipotent molecule. Melatonin, a versatile and ubiquitous antioxidant molecule, originally discovered as a hormone synthesized mainly in the pineal gland, has low toxicity and high efficacy in reducing oxidative damage, anti-inflammatory effects by regulation of multiple cellular pathways and properties to prevent excitotoxicity, among others. The purpose of this review is to show the multiple and diverse properties of melatonin, as a pleiotropic indole derivative, and its marked potential for improving human health against the most widely used chemical weapons.
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Affiliation(s)
- René Pita
- Chemical Defence Department, CBRN Defence School, Army Engineer School, 28240-Hoyo de Manzanares, Madrid, Spain
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Angelini DJ, Dorsey RM, Willis KL, Hong C, Moyer RA, Oyler J, Jensen NS, Salem H. Chemical warfare agent and biological toxin-induced pulmonary toxicity: could stem cells provide potential therapies? Inhal Toxicol 2013; 25:37-62. [DOI: 10.3109/08958378.2012.750406] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Abou-Donia MB, Abou-Donia MM, ElMasry EM, Monro JA, Mulder MFA. Autoantibodies to nervous system-specific proteins are elevated in sera of flight crew members: biomarkers for nervous system injury. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2013; 76:363-380. [PMID: 23557235 DOI: 10.1080/15287394.2013.765369] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
This descriptive study reports the results of assays performed to detect circulating autoantibodies in a panel of 7 proteins associated with the nervous system (NS) in sera of 12 healthy controls and a group of 34 flight crew members including both pilots and attendants who experienced adverse effects after exposure to air emissions sourced to the ventilation system in their aircrafts and subsequently sought medical attention. The proteins selected represent various types of proteins present in nerve cells that are affected by neuronal degeneration. In the sera samples from flight crew members and healthy controls, immunoglobin (IgG) was measured using Western blotting against neurofilament triplet proteins (NFP), tubulin, microtubule-associated tau proteins (tau), microtubule-associated protein-2 (MAP-2), myelin basic protein (MBP), glial fibrillary acidic protein (GFAP), and glial S100B protein. Significant elevation in levels of circulating IgG-class autoantibodies in flight crew members was found. A symptom-free pilot was sampled before symptoms and then again afterward. This pilot developed clinical problems after flying for 45 h in 10 d. Significant increases in autoantibodies were noted to most of the tested proteins in the serum of this pilot after exposure to air emissions. The levels of autoantibodies rose with worsening of his condition compared to the serum sample collected prior to exposure. After cessation of flying for a year, this pilot's clinical condition improved, and eventually he recovered and his serum autoantibodies against nervous system proteins decreased. The case study with this pilot demonstrates a temporal relationship between exposure to air emissions, clinical condition, and level of serum autoantibodies to nervous system-specific proteins. Overall, these results suggest the possible development of neuronal injury and gliosis in flight crew members anecdotally exposed to cabin air emissions containing organophosphates. Thus, increased circulating serum autoantibodies resulting from neuronal damage may be used as biomarkers for chemical-induced CNS injury.
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Affiliation(s)
- Mohamed B Abou-Donia
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA.
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Heterogeneity in the rat brain vasculature revealed by quantitative confocal analysis of endothelial barrier antigen and P-glycoprotein expression. J Cereb Blood Flow Metab 2012; 32:81-92. [PMID: 21792241 PMCID: PMC3323292 DOI: 10.1038/jcbfm.2011.109] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
While phenotypic endothelial heterogeneity is well documented in peripheral organs, it is only now being explored in the brain. We used confocal imaging of thick sections of rat brain to qualitatively and quantitatively examine the expression of two key markers of the blood-brain barrier (BBB) in the rat, P-glycoprotein (P-gp), and endothelial barrier antigen (EBA). We found that these markers were not uniformly distributed throughout the whole vasculature of the cortex and hippocampus. P-glycoprotein displayed a gradient of expression from an almost undetectable level in large penetrating arterioles to a high and uniform level in capillaries and venules. While EBA was lacking in all cerebral arterioles, regardless of their size, its expression varied greatly among endothelial cells in capillaries and venules, yielding a striking mosaic pattern. A detailed quantitative analysis of the distribution of these markers at the single cell level in capillaries is provided. These results challenge the view of a uniform BBB and suggest that regulatory mechanisms might differentially modulate BBB features not only among arterioles/capillaries/venules but also at the single cell level within the capillaries. Hypotheses are made regarding the underlying mechanisms and physiopathological consequences of this heterogeneity.
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RamaRao G, Bhattacharya BK. Multiple signal transduction pathways alterations during nerve agent toxicity. Toxicol Lett 2011; 208:16-22. [PMID: 22001750 DOI: 10.1016/j.toxlet.2011.09.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 09/21/2011] [Accepted: 09/22/2011] [Indexed: 02/06/2023]
Abstract
Nerve agent toxicity is primarily due to the synaptic build up of toxic levels of acetylcholine. The acute lethal effects of the nerve agents are generally attributed to respiratory failure caused by a combination of effects at both central and peripheral levels and are further complicated by copious secretions, muscle fasciculations, and convulsions. In addition to this, a range of non cholinergic effects have been observed. The development of effective treatment to block multiple effects resulting from nerve agent exposure is hampered by a limited understanding of the molecular changes responsible for their persistent effects. Excessive accumulation of acetylcholine leads to activation nicotinic and muscarinic acetylcholine receptors, these receptors activate diverse kind of cellular responses by distinct signaling pathways. Metabolism of cyclic nucleotides, membrane phospholipids, activation of a multitude of protein kinases and the induction of transcription factors are the key biochemical steps and pathways that have been investigated. This review will focus on the effects of nerve agents on signal transduction pathways; particularly, MAP kinases, protein kinase C isozymes, calcium calmodulin dependent protein kinase II (CaMKII) and on cytoskeletal proteins, calpain, and certain transcription factors and discusses how such changes may be involved in nerve agent induced neurotoxicity. Alterations in these key brain proteins could explain the neurological impairments following nerve agent exposure. A better understanding of the whole picture may lead to new pharmacological interventions aimed to improve or modulate those signal transduction pathways affected during nerve agent poisoning or associated pathologies that are responsible for neuronal disturbances.
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Affiliation(s)
- G RamaRao
- Biochemistry Division, Defence Research and Development Establishment, Jhansi Road, Gwalior, M.P., India.
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Early differential cell death and survival mechanisms initiate and contribute to the development of OPIDN: a study of molecular, cellular, and anatomical parameters. Toxicol Appl Pharmacol 2011; 256:348-59. [PMID: 21840330 DOI: 10.1016/j.taap.2011.07.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Revised: 07/28/2011] [Accepted: 07/28/2011] [Indexed: 01/30/2023]
Abstract
Organophosphorus-ester induced delayed neurotoxicity (OPIDN) is a neurodegenerative disorder characterized by ataxia progressing to paralysis with a concomitant central and peripheral, distal axonapathy. Diisopropylphosphorofluoridate (DFP) produces OPIDN in the chicken that results in mild ataxia in 7-14 days and severe paralysis as the disease progresses with a single dose. White leghorn layer hens were treated with DFP (1.7 mg/kg, sc) after prophylactic treatment with atropine (1mg/kg, sc) in normal saline and eserine (1mg/kg, sc) in dimethyl sulfoxide. Control groups were treated with vehicle propylene glycol (0.1 ml/kg, sc), atropine in normal saline and eserine in dimethyl sulfoxide. The hens were euthanized at different time points such as 1, 2, 5, 10 and 20 days, and the tissues from cerebrum, midbrain, cerebellum, brainstem and spinal cord were quickly dissected and frozen for mRNA (northern) studies. Northern blots were probed with BCL2, GADD45, beta actin, and 28S RNA to investigate their expression pattern. Another set of hens was treated for a series of time points and perfused with phosphate buffered saline and fixative for histological studies. Various staining protocols such as Hematoxylin and Eosin (H&E); Sevier-Munger; Cresyl echt Violet for Nissl substance; and Gallocynin stain for Nissl granules were used to assess various patterns of cell death and degenerative changes. Complex cell death mechanisms may be involved in the neuronal and axonal degeneration. These data indicate altered and differential mRNA expressions of BCL2 (anti apoptotic gene) and GADD45 (DNA damage inducible gene) in various tissues. Increased cell death and other degenerative changes noted in the susceptible regions (spinal cord and cerebellum) than the resistant region (cerebrum), may indicate complex molecular pathways via altered BCL2 and GADD45 gene expression, causing the homeostatic imbalance between cell survival and cell death mechanisms. Semi quantitative analysis revealed that the order of severity of damage declines from the spino-cerebellar, ventral, and dorsal tract respectively, suggesting neuroanatomical specificity. Thus, early activation of cell death and cell survival processes may play significant role in the clinical progression and syndromic clinical feature presentation of OPIDN.
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Spradling KD, Lumley LA, Robison CL, Meyerhoff JL, Dillman JF. Transcriptional responses of the nerve agent-sensitive brain regions amygdala, hippocampus, piriform cortex, septum, and thalamus following exposure to the organophosphonate anticholinesterase sarin. J Neuroinflammation 2011; 8:84. [PMID: 21777430 PMCID: PMC3180277 DOI: 10.1186/1742-2094-8-84] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Accepted: 07/21/2011] [Indexed: 11/22/2022] Open
Abstract
Background Although the acute toxicity of organophosphorus nerve agents is known to result from acetylcholinesterase inhibition, the molecular mechanisms involved in the development of neuropathology following nerve agent-induced seizure are not well understood. To help determine these pathways, we previously used microarray analysis to identify gene expression changes in the rat piriform cortex, a region of the rat brain sensitive to nerve agent exposure, over a 24-h time period following sarin-induced seizure. We found significant differences in gene expression profiles and identified secondary responses that potentially lead to brain injury and cell death. To advance our understanding of the molecular mechanisms involved in sarin-induced toxicity, we analyzed gene expression changes in four other areas of the rat brain known to be affected by nerve agent-induced seizure (amygdala, hippocampus, septum, and thalamus). Methods We compared the transcriptional response of these four brain regions to sarin-induced seizure with the response previously characterized in the piriform cortex. In this study, rats were challenged with 1.0 × LD50 sarin and subsequently treated with atropine sulfate, 2-pyridine aldoxime methylchloride, and diazepam. The four brain regions were collected at 0.25, 1, 3, 6, and 24 h after seizure onset, and total RNA was processed for microarray analysis. Results Principal component analysis identified brain region and time following seizure onset as major sources of variability within the dataset. Analysis of variance identified genes significantly changed following sarin-induced seizure, and gene ontology analysis identified biological pathways, functions, and networks of genes significantly affected by sarin-induced seizure over the 24-h time course. Many of the molecular functions and pathways identified as being most significant across all of the brain regions were indicative of an inflammatory response. There were also a number of molecular responses that were unique for each brain region, with the thalamus having the most distinct response to nerve agent-induced seizure. Conclusions Identifying the molecular mechanisms involved in sarin-induced neurotoxicity in these sensitive brain regions will facilitate the development of novel therapeutics that can potentially provide broad-spectrum protection in five areas of the central nervous system known to be damaged by nerve agent-induced seizure.
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Affiliation(s)
- Kimberly D Spradling
- Cell and Molecular Biology Branch, US Army Medical Research Institute of Chemical Defense (USAMRICD), 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400, USA
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The Molecular Toxicology of Chemical Warfare Nerve Agents. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/b978-0-444-53864-2.00003-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Carpentier P, Foquin A, Dorandeu F. Hypertonic mannitol in mice poisoned by a convulsive dose of soman: antilethal activity without neuroprotection. Toxicology 2009; 268:78-88. [PMID: 20003915 DOI: 10.1016/j.tox.2009.12.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Revised: 11/30/2009] [Accepted: 12/01/2009] [Indexed: 11/16/2022]
Abstract
A convulsive dose of soman induces seizure-related brain damage (SRBD), including cerebral edema (CE) and cell death. In 1993, an American study demonstrated that hypertonic mannitol (Mann) intravenously (i.v.) administered 1 min and 5h post-soman was an effective neuroprotectant in intoxicated rats. Using a similar protocol, we recently failed to reproduce this success in intoxicated mice. In the present study, also performed in mice, the persistence or the amplitude of the osmotic load was increased by reducing the time interval between two injections of Mann or by augmenting the number of injections. Mice were pre-treated with the oxime HI-6 and then intoxicated with a convulsive dose of soman (172 microg/kg). Afterward, they were administered a first i.v. bolus of Mann 20% 1 min post-challenge and a second one either 5, or 2, or 1h after. Additional animals were given either one (1 min post-soman), or two (1 min and 1h post-soman), or three (1 min, 1 and 2h post-soman) series of three injections of Mann at 5 min intervals. Non-intoxicated mice treated with Mann (same protocols as above) and intoxicated mice treated with Mann vehicle (saline) served as controls. At 24h post-intoxication, the survivors were sacrificed and their brains prepared for quantitative histological assessment of cell damage, CE, and ventricle size. Whatever the protocol, Mann had no effect on soman-induced convulsions but did provide considerable antilethal activity. Histologically, Mann did not reduce the cell damage or CE. It even showed a dose-dependent trend toward aggravation of SRBD in some regions and promoted subarachnoid hemorrhages. Conversely, in one of the treatment protocol, it reduced soman-induced enlargement of ventricle size. Although treatment with hypertonic Mann showed some benefit on mortality and ventricle size, it failed to be an effective neuroprotector in soman-intoxicated mice and even increased the detrimental impact of soman at the cerebral level. Therefore, no clear recommendation could be drawn from the present study in view of a possible clinical use of hyperosmolar treatment in the medical management of soman poisoning.
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Affiliation(s)
- Pierre Carpentier
- Institut de Recherche Biomédicale des Armées, Centre de Recherches du Service de Santé des Armées, Département de Toxicologie, BP87, F-38702 La Tronche Cedex, France.
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Damodaran TV, Gupta RP, Attia MK, B. Abou-Donia M. DFP initiated early alterations of PKA/p-CREB pathway and differential persistence of β-tubulin subtypes in the CNS of hens contributes to OPIDN. Toxicol Appl Pharmacol 2009; 240:132-42. [DOI: 10.1016/j.taap.2009.07.035] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Revised: 07/23/2009] [Accepted: 07/24/2009] [Indexed: 10/20/2022]
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Jokanović M. Medical treatment of acute poisoning with organophosphorus and carbamate pesticides. Toxicol Lett 2009; 190:107-15. [PMID: 19651196 DOI: 10.1016/j.toxlet.2009.07.025] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2009] [Accepted: 07/27/2009] [Indexed: 11/16/2022]
Abstract
Organophosphorus compounds (OPs) are used as pesticides and developed as warfare nerve agents such as tabun, soman, sarin, VX and others. Exposure to even small amounts of an OP can be fatal and death is usually caused by respiratory failure. The mechanism of OP poisoning involves inhibition of acetylcholinesterase (AChE) leading to inactivation of the enzyme which has an important role in neurotransmission. AChE inhibition results in the accumulation of acetylcholine at cholinergic receptor sites, producing continuous stimulation of cholinergic fibers throughout the nervous systems. During more than five decades, pyridinium oximes have been developed as therapeutic agents used in the medical treatment of poisoning with OP. They act by reactivation of AChE inhibited by OP. However, they differ in their activity in poisoning with pesticides and warfare nerve agents and there is still no universal broad-spectrum oxime capable of protecting against all known OP. In spite of enormous efforts devoted to development of new pyridinium oximes as potential antidotes against poisoning with OP only four compounds so far have found its application in human medicine. Presently, a combination of an antimuscarinic agent, e.g. atropine, AChE reactivator such as one of the recommended pyridinium oximes (pralidoxime, trimedoxime, obidoxime and HI-6) and diazepam are used for the treatment of OP poisoning in humans. In this article the available data related to medical treatment of poisoning with OP pesticides are reviewed and the current recommendations are presented.
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Affiliation(s)
- Milan Jokanović
- Faculty of Medicine, University of Nish, Nish, Serbia; Academy of Sciences and Arts of Republic Srpska, Banja Luka, Republic Srpska, Bosnia and Herzegovina.
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