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Zhao H, Liu Y, Cai N, Liao X, Tang L, Wang Y. Endocannabinoid Hydrolase Inhibitors: Potential Novel Anxiolytic Drugs. Drug Des Devel Ther 2024; 18:2143-2167. [PMID: 38882045 PMCID: PMC11179644 DOI: 10.2147/dddt.s462785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Accepted: 05/27/2024] [Indexed: 06/18/2024] Open
Abstract
Over the past decade, the idea of targeting the endocannabinoid system to treat anxiety disorders has received increasing attention. Previous studies focused more on developing cannabinoid receptor agonists or supplementing exogenous cannabinoids, which are prone to various adverse effects due to their strong pharmacological activity and poor receptor selectivity, limiting their application in clinical research. Endocannabinoid hydrolase inhibitors are considered to be the most promising development strategies for the treatment of anxiety disorders. More recent efforts have emphasized that inhibition of two major endogenous cannabinoid hydrolases, monoacylglycerol lipase (MAGL) and fatty acid amide hydrolase (FAAH), indirectly activates cannabinoid receptors by increasing endogenous cannabinoid levels in the synaptic gap, circumventing receptor desensitization resulting from direct enhancement of endogenous cannabinoid signaling. In this review, we comprehensively summarize the anxiolytic effects of MAGL and FAAH inhibitors and their potential pharmacological mechanisms, highlight reported novel inhibitors or natural products, and provide an outlook on future directions in this field.
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Affiliation(s)
- Hongqing Zhao
- Science & Technology Innovation Center, Hunan University of Chinese Medicine, Changsha, Hunan, People’s Republic of China
- Hunan Key Laboratory of Traditional Chinese Medicine Prevention & Treatment of Depressive Diseases, Changsha, Hunan, People’s Republic of China
| | - Yang Liu
- Science & Technology Innovation Center, Hunan University of Chinese Medicine, Changsha, Hunan, People’s Republic of China
- Hunan Key Laboratory of Traditional Chinese Medicine Prevention & Treatment of Depressive Diseases, Changsha, Hunan, People’s Republic of China
| | - Na Cai
- Outpatient Department, the First Affiliated Hospital of Hunan University of Chinese Medicine, Changsha, Hunan, People’s Republic of China
| | - Xiaolin Liao
- Science & Technology Innovation Center, Hunan University of Chinese Medicine, Changsha, Hunan, People’s Republic of China
- Hunan Key Laboratory of Traditional Chinese Medicine Prevention & Treatment of Depressive Diseases, Changsha, Hunan, People’s Republic of China
| | - Lin Tang
- Hunan Key Laboratory of Traditional Chinese Medicine Prevention & Treatment of Depressive Diseases, Changsha, Hunan, People’s Republic of China
- Department of Pharmacy, the First Affiliated Hospital of Hunan University of Chinese Medicine, Changsha, Hunan, People’s Republic of China
| | - Yuhong Wang
- Science & Technology Innovation Center, Hunan University of Chinese Medicine, Changsha, Hunan, People’s Republic of China
- Hunan Key Laboratory of Traditional Chinese Medicine Prevention & Treatment of Depressive Diseases, Changsha, Hunan, People’s Republic of China
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2
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Cui Sun M, Otálora-Alcaraz A, Prenderville JA, Downer EJ. Toll-like receptor signalling as a cannabinoid target. Biochem Pharmacol 2024; 222:116082. [PMID: 38438052 DOI: 10.1016/j.bcp.2024.116082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 02/01/2024] [Accepted: 02/22/2024] [Indexed: 03/06/2024]
Abstract
Toll-like receptors (TLRs) have become a focus in biomedicine and biomedical research given the roles of this unique family of innate immune proteins in immune activation, infection, and autoimmunity. It is evident that TLR dysregulation, and subsequent alterations in TLR-mediated inflammatory signalling, can contribute to disease pathogenesis, and TLR targeted therapies are in development. This review highlights evidence that cannabinoids are key regulators of TLR signalling. Cannabinoids include component of the plant Cannabis sativa L. (C. sativa), synthetic and endogenous ligands, and overall represent a class of compounds whose therapeutic potential and mechanism of action continues to be elucidated. Cannabinoid-based medicines are in the clinic, and are furthermore under intense investigation for broad clinical development to manage symptoms of a range of disorders. In this review, we present an overview of research evidence that signalling linked to a range of TLRs is targeted by cannabinoids, and such cannabinoid mediated effects represent therapeutic avenues for further investigation. First, we provide an overview of TLRs, adaptors and key signalling events, alongside a summary of evidence that TLRs are linked to disease pathologies. Next, we discuss the cannabinoids system and the development of cannabinoid-based therapeutics. Finally, for the bulk of this review, we systematically outline the evidence that cannabinoids (plant-derived cannabinoids, synthetic cannabinoids, and endogenous cannabinoid ligands) can cross-talk with innate immune signalling governed by TLRs, focusing specifically on each member of the TLR family. Cannabinoids should be considered as key regulators of signalling controlled by TLRs, and such regulation should be a major focus in terms of the anti-inflammatory propensity of the cannabinoid system.
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Affiliation(s)
- Melody Cui Sun
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Almudena Otálora-Alcaraz
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Jack A Prenderville
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland; Transpharmation Ireland Limited, Institute of Neuroscience, Trinity College, Dublin 2, Ireland
| | - Eric J Downer
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland.
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3
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Fusse EJ, Scarante FF, Vicente MA, Marrubia MM, Turcato F, Scomparin DS, Ribeiro MA, Figueiredo MJ, Brigante TAV, Guimarães FS, Campos AC. Anxiogenic doses of rapamycin prevent URB597-induced anti-stress effects in socially defeated mice. Neurosci Lett 2024; 818:137519. [PMID: 37852528 DOI: 10.1016/j.neulet.2023.137519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 10/06/2023] [Accepted: 10/11/2023] [Indexed: 10/20/2023]
Abstract
Repeated exposure to psychosocial stress modulates the endocannabinoid system, particularly anandamide (AEA) signaling in brain regions associated with emotional distress. The mTOR protein regulates various neuroplastic processes in the brain disrupted by stress, including adult hippocampal neurogenesis. This kinase has been implicated in multiple effects of cannabinoid drugs and the anti-stress behavioral effects of psychoactive drugs. Therefore, our hypothesis is that enhancing AEA signaling via pharmacological inhibition of the fatty acid amide hydrolase (FAAH) enzyme induces an anti-stress behavioral effect through an mTOR-dependent mechanism. To test this hypothesis, male C57Bl6 mice were exposed to social defeat stress (SDS) for 7 days and received daily treatment with either vehicle or different doses of the FAAH inhibitor, URB597 (0.1; 0.3; 1 mg/Kg), alone or combined with rapamycin. The results suggested that URB597 induced an inverted U-shaped dose-response curve in mice subjected to SDS (with the intermediate dose of 0.3 mg/kg being anxiolytic, and the higher tested dose of 1 mg/Kg being anxiogenic). In a second independent experiment, rapamycin treatment induced an anxiogenic-like response in control mice. However, in the presence of rapamycin, the anxiolytic dose of URB597 treatment failed to reduce stress-induced anxiety behaviors in mice. SDS exposure altered the hippocampal expression of the mTOR scaffold protein Raptor. Furthermore, the anxiogenic dose of URB597 decreased the absolute number of migrating doublecortin (DCX)-positive cells in the dentate gyrus, suggesting an anti-anxiety effect independent of newly generated/immature neurons. Therefore, our results indicate that in mice exposed to repeated psychosocial stress, URB597 fails to counteract the anxiogenic-like response induced by the pharmacological dampening of mTOR signaling.
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Affiliation(s)
- Eduardo J Fusse
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Franciele F Scarante
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Maria A Vicente
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Mariana M Marrubia
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Flávia Turcato
- Department of Neurological Surgery, Case Western Reserve University, Cleveland, USA
| | - Davi S Scomparin
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Melissa A Ribeiro
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Maria J Figueiredo
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Tamires A V Brigante
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Francisco S Guimarães
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil
| | - Alline C Campos
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, 3900 Bandeirantes Ave, Ribeirão Preto, Brazil.
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4
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Papa A, Pasquini S, Galvani F, Cammarota M, Contri C, Carullo G, Gemma S, Ramunno A, Lamponi S, Gorelli B, Saponara S, Varani K, Mor M, Campiani G, Boscia F, Vincenzi F, Lodola A, Butini S. Development of potent and selective FAAH inhibitors with improved drug-like properties as potential tools to treat neuroinflammatory conditions. Eur J Med Chem 2023; 246:114952. [PMID: 36462439 DOI: 10.1016/j.ejmech.2022.114952] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/10/2022] [Accepted: 11/20/2022] [Indexed: 11/26/2022]
Abstract
The neuroprotective performance against neuroinflammation of the endocannabinoid system (ECS) can be remarkably improved by indirect stimulation mediated by the pharmacological inhibition of the key ECS catabolic enzyme fatty acid amide hydrolase (FAAH). Based on our previous works and aiming to discover new selective FAAH inhibitors , we herein reported a new series of carbamate-based FAAH inhibitors (4a-t) which showed improved drug disposition properties compared to the previously reported analogues 2a-b. The introduction of ionizable functions allowed us to obtain new FAAH inhibitors of nanomolar potency characterized by good water solubility and chemical stability at physiological pH. Interesting structure-activity relationships (SARs), deeply analyzed by molecular docking and molecular dynamic (MD) simulations, were obtained. All the newly developed inhibitors showed an excellent selectivity profile evaluated against monoacylglycerol lipase and cannabinoid receptors. The reversible mechanism of action was determined by a rapid dilution assay. Absence of toxicity was confirmed in mouse fibroblasts NIH3T3 (for compounds 4e, 4g, 4n-o, and 4s) and in human astrocytes cell line 1321N1 (for compounds 4e, 4n, and 4s). The absence of undesired cardiac effects was also confirmed for compound 4n. Selected analogues (compounds 4e, 4g, 4n, and 4s) were able to reduce oxidative stress in 1321N1 astrocytes and exhibited notable neuroprotective effects when tested in an ex vivo model of neuroinflammation.
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Affiliation(s)
- Alessandro Papa
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via Aldo Moro 2, 53100, Siena, Italy
| | - Silvia Pasquini
- Dipartimento di Scienze Chimiche, Farmaceutiche e Agrarie, Università degli Studi di Ferrara, Via Borsari 46, 44121, Ferrara, Italy
| | - Francesca Galvani
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle Scienze 27/A, 43124, Parma, Italy
| | - Mariarosaria Cammarota
- Divisione di Farmacologia, Dipartimento di Neuroscienze e Scienze Riproduttive ed Odontostomatologiche, Università degli Studi di Napoli Federico II, Via Pansini 5, 80131, Napoli, Italy
| | - Chiara Contri
- Dipartimento di Medicina Traslazionale, Università degli Studi di Ferrara, Via Borsari 46, 44121, Ferrara, Italy
| | - Gabriele Carullo
- Dipartiment di Scienze della Vita, Università degli Studi di Siena, Via Aldo Moro 2, 53100, Siena, Italy
| | - Sandra Gemma
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via Aldo Moro 2, 53100, Siena, Italy
| | - Anna Ramunno
- Dipartimento di Farmacia, Università degli Studi di Salerno, Viale Giovanni Paolo II 132, 84084, Fisciano (SA), Italy
| | - Stefania Lamponi
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via Aldo Moro 2, 53100, Siena, Italy
| | - Beatrice Gorelli
- Dipartiment di Scienze della Vita, Università degli Studi di Siena, Via Aldo Moro 2, 53100, Siena, Italy
| | - Simona Saponara
- Dipartiment di Scienze della Vita, Università degli Studi di Siena, Via Aldo Moro 2, 53100, Siena, Italy
| | - Katia Varani
- Dipartimento di Medicina Traslazionale, Università degli Studi di Ferrara, Via Borsari 46, 44121, Ferrara, Italy
| | - Marco Mor
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle Scienze 27/A, 43124, Parma, Italy; Microbiome Research Hub, Università degli Studi di Parma, Parco Area delle Scienze 11/A, I-43124, Parma, Italy
| | - Giuseppe Campiani
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via Aldo Moro 2, 53100, Siena, Italy
| | - Francesca Boscia
- Divisione di Farmacologia, Dipartimento di Neuroscienze e Scienze Riproduttive ed Odontostomatologiche, Università degli Studi di Napoli Federico II, Via Pansini 5, 80131, Napoli, Italy
| | - Fabrizio Vincenzi
- Dipartimento di Medicina Traslazionale, Università degli Studi di Ferrara, Via Borsari 46, 44121, Ferrara, Italy
| | - Alessio Lodola
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle Scienze 27/A, 43124, Parma, Italy
| | - Stefania Butini
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via Aldo Moro 2, 53100, Siena, Italy.
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5
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Cammarota M, Ferlenghi F, Vacondio F, Vincenzi F, Varani K, Bedini A, Rivara S, Mor M, Boscia F. Combined targeting of fatty acid amide hydrolase and melatonin receptors promotes neuroprotection and stimulates inflammation resolution in rats. Br J Pharmacol 2022; 180:1316-1338. [PMID: 36526591 DOI: 10.1111/bph.16014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 11/09/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND AND PURPOSE Devising novel strategies to therapeutically favour inflammation resolution and provide neuroprotection is an unmet clinical need. Enhancing endocannabinoid tone by inhibiting the catabolic enzyme fatty acid amide hydrolase (FAAH), or stimulating melatonin receptors has therapeutic potential to treat neuropathological states in which neuroinflammation plays a central role. EXPERIMENTAL APPROACH A rodent hippocampal explant model of inflammatory injury was used to assess the effects of UCM1341, a dual-acting compound with FAAH inhibitory action and agonist activity at melatonin receptors, against neuroinflammatory damage. FAAH activity was measured by a radiometric assay, and N-acylethanolamine levels were assessed by HPLC-MS/MS methods. FAAH distribution, evolution of inflammation and the contribution of UCM1341 to the expression of proteins controlling macrophage behaviour were investigated by biochemical and confocal analyses. KEY RESULTS UCM1341 exhibited greater neuroprotection against neuroinflammatory degeneration, compared with the reference compounds URB597 (FAAH inhibitor) and melatonin. During neuroinflammation, UCM1341 augmented the levels of anandamide and N-oleoylethanolamine, but not N-palmitoylethanolamine, up-regulated PPAR-α levels, attenuated demyelination and prevented the release of TNF-α. UCM1341 modulated inflammatory responses by contributing to microglia/macrophage polarization, stimulating formation of lipid-laden macrophages and regulating expression of proteins controlling cholesterol metabolism and efflux. The neuroprotective effects of UCM1341 were prevented by PPARα, TRPV1 and melatonin receptor antagonists. CONCLUSION AND IMPLICATIONS UCM1341, by enhancing endocannabinoid and melatoninergic signalling, benefits neuroprotection and stimulates inflammation resolution pathways. Our findings provide an encouraging prospect of therapeutically targeting endocannabinoid and melatoninergic systems in inflammatory demyelinating states in the CNS.
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Affiliation(s)
- Mariarosaria Cammarota
- Division of Pharmacology, Department of Neuroscience, Reproductive Sciences and Dentistry, School of Medicine, Federico II University of Naples, Naples, Italy
| | | | | | - Fabrizio Vincenzi
- Department of Translational Medicine, University of Ferrara, Ferrara, Italy
| | - Katia Varani
- Department of Translational Medicine, University of Ferrara, Ferrara, Italy
| | - Annalida Bedini
- Department of Biomolecular Sciences, University of Urbino 'Carlo Bo', Urbino, Italy
| | - Silvia Rivara
- Department of Food and Drug, University of Parma, Parma, Italy
| | - Marco Mor
- Department of Food and Drug, University of Parma, Parma, Italy
| | - Francesca Boscia
- Division of Pharmacology, Department of Neuroscience, Reproductive Sciences and Dentistry, School of Medicine, Federico II University of Naples, Naples, Italy
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6
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Swindell WR, Bojanowski K, Singh P, Randhawa M, Chaudhuri RK. Bakuchiol and ethyl (linoleate/oleate) synergistically modulate endocannabinoid tone in keratinocytes and repress inflammatory pathway mRNAs. JID INNOVATIONS 2022; 3:100178. [PMID: 36992949 PMCID: PMC10041561 DOI: 10.1016/j.xjidi.2022.100178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 09/23/2022] [Accepted: 10/20/2022] [Indexed: 12/27/2022] Open
Abstract
The endocannabinoid (eCB) system plays an active role in epidermal homeostasis. Phytocannabinoids such as cannabidiol modulate this system but also act through eCB-independent mechanisms. This study evaluated the effects of cannabidiol, bakuchiol (BAK), and ethyl (linoleate/oleate) (ELN) in keratinocytes and reconstituted human epidermis. Molecular docking simulations showed that each compound binds the active site of the eCB carrier FABP5. However, BAK and ethyl linoleate bound this site with the highest affinity when combined 1:1 (w/w), and in vitro assays showed that BAK + ELN most effectively inhibited FABP5 and fatty acid amide hydrolase. In TNF-stimulated keratinocytes, BAK + ELN reversed TNF-induced expression shifts and uniquely downregulated type I IFN genes and PTGS2 (COX2). BAK + ELN also repressed expression of genes linked to keratinocyte differentiation but upregulated those associated with proliferation. Finally, BAK + ELN inhibited cortisol secretion in reconstituted human epidermis skin (not observed with cannabidiol). These results support a model in which BAK and ELN synergistically interact to inhibit eCB degradation, favoring eCB mobilization and inhibition of downstream inflammatory mediators (e.g., TNF, COX-2, type I IFN). A topical combination of these ingredients may thus enhance cutaneous eCB tone or potentiate other modulators, suggesting novel ways to modulate the eCB system for innovative skincare product development.
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Affiliation(s)
- William R. Swindell
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
- Correspondence: William R. Swindell, Department of Internal Medicine, UT Southwestern Medical Center, 5959 Harry Hines Boulevard, Ste 7.700, Dallas, Texas 75390-9175, USA.
| | | | - Parvesh Singh
- School of Chemistry & Physics, University of KwaZulu-Natal, Westville, South Africa
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7
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Zhang Q, Li Y, Yu J, Yin C, Guo J, Zhao J, Wang Q. TLR3 deletion inhibits programmed necrosis of brain cells in neonatal mice with sevoflurane-induced cognitive dysfunction. Aging (Albany NY) 2022; 14:4714-4727. [PMID: 35666713 PMCID: PMC9217712 DOI: 10.18632/aging.204092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 05/07/2022] [Indexed: 11/25/2022]
Abstract
This research aimed to explore the influence of TLR deletion on sevoflurane-induced postoperative cognitive dysfunction in neonatal mice. Herein, WT and TLR3 KO neonatal mice, each with 24, were randomly divided into control group, sevoflurane group, and TLR3−/−+sevoflurane group. The hippocampal neurons of WT, TLR3 KO and RIP3 KO neonatal mice in C group, SEV group, TLR3−/−+SEV group and RIP3−/−+SEV group were extracted for in vitro experiments. The results revealed the degeneration and necrosis of nerve cells in SEV group. Microscopic findings indicated that nerve cells showed shrinkage and nuclear hyperchromatism, along with lessening or even disappearance of nuclei and enlargement of cell spaces, and apoptotic cells in the brain tissues were evidently increased. Compared with SEV group, TLR3−/−+SEV group displayed reductions in these phenomena. Additionally, SEV group showed the reduced SHP2 expression and the increased expressions of proteins associated with TLR signaling pathway and apoptosis. Furthermore, there were no obvious differences in the expressions of such proteins in hippocampal neurons between RIP3−/−+SEV and TLR3−/−+SEV groups. The results confirmed that inhibiting RIP3 phosphorylation and suppressing TLR3 expressions exerted the same influence on the expressions of these proteins in the hippocampus of neonatal mice with sevoflurane-induced cognitive dysfunction. Based on these, it is speculated that TLR3 influences neonatal mice with sevoflurane-induced cognitive dysfunction probably by regulating RIP3 phosphorylation.
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Affiliation(s)
- Qi Zhang
- Department of Anesthesiology, The Third Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei, China.,Department of Anesthesiology, Children's Hospital of Hebei Province Affiliated to Hebei Medical University, Shijiazhuang 050031, Hebei, China
| | - Yanan Li
- Department of Anesthesiology, The Third Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei, China
| | - Jiaxu Yu
- Department of Anesthesiology, The Third Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei, China
| | - Chunping Yin
- Department of Anesthesiology, The Third Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei, China
| | - Junfei Guo
- Department of Orthopedics, The Third Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei, China
| | - Juan Zhao
- Experimental Teaching Center of Hebei Medical University, Shijiazhuang 050017, Hebei, China
| | - Qiujun Wang
- Department of Anesthesiology, The Third Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei, China
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8
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Reusch N, Ravichandran KA, Olabiyi BF, Komorowska-Müller JA, Hansen JN, Ulas T, Beyer M, Zimmer A, Schmöle AC. Cannabinoid receptor 2 is necessary to induce toll-like receptor-mediated microglial activation. Glia 2021; 70:71-88. [PMID: 34499767 DOI: 10.1002/glia.24089] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/25/2021] [Accepted: 08/26/2021] [Indexed: 01/17/2023]
Abstract
The tight regulation of microglia activity is key for precise responses to potential threats, while uncontrolled and exacerbated microglial activity is neurotoxic. Microglial toll-like receptors (TLRs) are indispensable for sensing different types of assaults and triggering an innate immune response. Cannabinoid receptor 2 (CB2) signaling is a key pathway to control microglial homeostasis and activation, and its activation is connected to changes in microglial activity. We aimed to investigate how CB2 signaling impacts TLR-mediated microglial activation. Here, we demonstrate that deletion of CB2 causes a dampened transcriptional response to prototypic TLR ligands in microglia. Loss of CB2 results in distinct microglial gene expression profiles, morphology, and activation. We show that the CB2-mediated attenuation of TLR-induced microglial activation is mainly p38 MAPK-dependent. Taken together, we demonstrate that CB2 expression and signaling are necessary to fine-tune TLR-induced activation programs in microglia.
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Affiliation(s)
- Nico Reusch
- Systems Medicine, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Genomics and Immunoregulation, Life and Medical Sciences Institute (LIMES), Bonn, Germany
| | | | | | - Joanna Agnieszka Komorowska-Müller
- Institute for Molecular Psychiatry, Medical Faculty, University of Bonn, Bonn, Germany.,International Max Planck Research School for Brain and Behavior, University of Bonn, Bonn, Germany
| | - Jan N Hansen
- Institute of Innate Immunity, Biophysical Imaging, Medical Faculty, University of Bonn, Bonn, Germany
| | - Thomas Ulas
- Systems Medicine, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Genomics and Immunoregulation, Life and Medical Sciences Institute (LIMES), Bonn, Germany.,Platform for Single Cell Genomics and Epigenomics (PRECISE), German Center for Neurodegenerative Diseases (DZNE), University of Bonn, Bonn, Germany
| | - Marc Beyer
- Platform for Single Cell Genomics and Epigenomics (PRECISE), German Center for Neurodegenerative Diseases (DZNE), University of Bonn, Bonn, Germany.,Molecular Immunology in Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Andreas Zimmer
- Institute for Molecular Psychiatry, Medical Faculty, University of Bonn, Bonn, Germany
| | - Anne-Caroline Schmöle
- Institute for Molecular Psychiatry, Medical Faculty, University of Bonn, Bonn, Germany
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9
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Flannery LE, Kerr DM, Hughes EM, Kelly C, Costello J, Thornton AM, Humphrey RM, Finn DP, Roche M. N-acylethanolamine regulation of TLR3-induced hyperthermia and neuroinflammatory gene expression: A role for PPARα. J Neuroimmunol 2021; 358:577654. [PMID: 34265624 PMCID: PMC8243641 DOI: 10.1016/j.jneuroim.2021.577654] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/11/2021] [Accepted: 06/28/2021] [Indexed: 12/12/2022]
Abstract
Increasing evidence suggests that SARS-CoV-2, the virus responsible for the COVID-19 pandemic, is associated with increased risk of developing neurological or psychiatric conditions such as depression, anxiety or dementia. While the precise mechanism underlying this association is unknown, aberrant activation of toll-like receptor (TLR)3, a viral recognizing pattern recognition receptor, may play a key role. Synthetic cannabinoids and enhancing cannabinoid tone via inhibition of fatty acid amide hydrolase (FAAH) has been demonstrated to modulate TLR3-induced neuroimmune responses and associated sickness behaviour. However, the role of individual FAAH substrates, and the receptor mechanisms mediating these effects, are unknown. The present study examined the effects of intracerebral or systemic administration of the FAAH substrates N-oleoylethanolamide (OEA), N-palmitoylethanolamide (PEA) or the anandamide (AEA) analogue meth-AEA on hyperthermia and hypothalamic inflammatory gene expression following administration of the TLR3 agonist, and viral mimetic, poly I:C. The data demonstrate that meth-AEA does not alter TLR3-induced hyperthermia or hypothalamic inflammatory gene expression. In comparison, OEA and PEA attenuated the TLR3-induced hyperthermia, although only OEA attenuated the expression of hyperthermia-related genes (IL-1β, iNOS, COX2 and m-PGES) in the hypothalamus. OEA, but not PEA, attenuated TLR3-induced increases in the expression of all IRF- and NFκB-related genes examined in the hypothalamus, but not in the spleen. Antagonism of PPARα prevented the OEA-induced attenuation of IRF- and NFκB-related genes in the hypothalamus following TLR3 activation but did not significantly alter temperature. PPARα agonism did not alter TLR3-induced hyperthermia or hypothalamic inflammatory gene expression. These data indicate that OEA may be the primary FAAH substrate that modulates TLR3-induced neuroinflammation and hyperthermia, effects partially mediated by PPARα.
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Affiliation(s)
- Lisa E Flannery
- Physiology, National University of Ireland, Galway, Ireland; Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - Daniel M Kerr
- Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, Ireland; Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - Edel M Hughes
- Physiology, National University of Ireland, Galway, Ireland
| | - Colm Kelly
- Physiology, National University of Ireland, Galway, Ireland
| | | | | | - Rachel M Humphrey
- Physiology, National University of Ireland, Galway, Ireland; Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - David P Finn
- Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, Ireland; Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - Michelle Roche
- Physiology, National University of Ireland, Galway, Ireland; Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland.
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10
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CB2 Receptor in Microglia: The Guardian of Self-Control. Int J Mol Sci 2020; 22:ijms22010019. [PMID: 33375006 PMCID: PMC7792761 DOI: 10.3390/ijms22010019] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 12/16/2020] [Accepted: 12/18/2020] [Indexed: 12/12/2022] Open
Abstract
Microglia are key to maintaining the homeostasis of the brain. These immune cells of the brain can be our biggest ally in fighting infections, but can worsen pathology or hinder recovery when uncontrolled. Thus, understanding how microglia contribute to neuroinflammatory processes and how their activity can be controlled is of great importance. It is known that activation of endocannabinoid system, and especially the cannabinoid type 2 receptor (CB2R), decreases inflammation. Alongside its non-psychoactive effect, it makes the CB2R receptor a perfect target for treating diseases accompanied by neuroinflammation including neurodegenerative diseases. However, the exact mechanisms by which CB2R regulates microglial activity are not yet understood. Here, we review the current knowledge on the roles of microglial CB2R from in vitro and in vivo studies. We look into CB2R function under physiological and pathological conditions and focus on four different disease models representing chronic and acute inflammation. We highlight open questions and controversies and provide an update on the latest discoveries that were enabled by the development of novel technologies. Also, we discuss the recent findings on the role of microglia CB2R in cognition and its role in neuron–microglia communication.
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11
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Wang X, Yu H, Wang C, Liu Y, You J, Wang P, Xu G, Shen H, Yao H, Lan X, Zhao R, Wu X, Zhang G. Chronic ethanol exposure induces neuroinflammation in H4 cells through TLR3 / NF-κB pathway and anxiety-like behavior in male C57BL/6 mice. Toxicology 2020; 446:152625. [PMID: 33161052 DOI: 10.1016/j.tox.2020.152625] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 10/22/2020] [Accepted: 11/01/2020] [Indexed: 02/08/2023]
Abstract
Chronic alcoholism has become a major public health problem. Long-term and excessive drinking can lead to a variety of diseases. Chronic ethanol exposure can induce neuroinflammation and anxiety-like behavior, and this may be induced through the Toll-like receptor 3/nuclear factor-κB (TLR3/NF-κB) pathway. Animal experiments were performed using healthy adult male C57BL/6 N mice given 10 % (m/V) or 20 % ethanol solution as the only choice of drinkable fluid for 60, 90 or 180 d. In cell culture experiments, H4 human glioma cells were treated with 100 mM ethanol for 2 d, with the TLR3 gene silenced by RNAi and NF-κB inhibited by ammonium pyrrolidine dithiocarbamate (PDTC, 10 μM). After treatment with ethanol solution for a specific time, the anxiety-like behavior of the mice was tested using the open field test and the elevated plus maze test. Western blotting was used to detect the expression of TLR3, TLR4, NF-κB, IL-1β, IL-6, and TNF-α in the mouse hippocampus and H4 cells. The expression of IL-1β, IL-6 and TNF-α in the supernatant of cell culture medium was detected by ELISA. The open field test showed a decrease in time spent in the central area, and the elevated plus maze test showed a decrease in activity time in the open arm region. These behavioral tests indicated that ethanol caused anxiety-like behavior in mice. The expression levels of TLR3, TLR4, NF-κB, IL-1β, IL-6, and TNF-α increased after ethanol exposure in both the hippocampus of mice and H4 cells. Silencing of the TLR3 gene by RNAi or inhibition of NF-κB by PDTC attenuated the ethanol-induced increase in the expression of inflammatory factors in H4 cells. These findings indicated that chronic ethanol exposure increases the expression of TLR3 and NF-κB and produces neuroinflammation and anxiety-like behavior in male C57BL/6 mice and that ethanol-induced neuroinflammation can be caused through the TLR3/NF-κB pathway.
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Affiliation(s)
- Xiaolong Wang
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China
| | - Hao Yu
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China
| | - Changliang Wang
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China; The People's Procuratorate of Liaoning Province Judicial Authentication Center, Shenyang, Liaoning, 110032, PR China; Collaborative Laboratory of Intelligentized Forensic Science (CLIFS), Shenyang, Liaoning, 110032, PR China
| | - Yang Liu
- The People's Procuratorate of Liaoning Province Judicial Authentication Center, Shenyang, Liaoning, 110032, PR China; Collaborative Laboratory of Intelligentized Forensic Science (CLIFS), Shenyang, Liaoning, 110032, PR China
| | - Jiabin You
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China
| | - Pengfei Wang
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China
| | - Guohui Xu
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China
| | - Hui Shen
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China
| | - Hui Yao
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China
| | - Xinze Lan
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China
| | - Rui Zhao
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China
| | - Xu Wu
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China.
| | - Guohua Zhang
- Department of Forensic Pathology, School of Forensic Medicine, China Medical University, Shenyang, Liaoning, 110122, PR China.
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12
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Fitzpatrick JM, Minogue E, Curham L, Tyrrell H, Gavigan P, Hind W, Downer EJ. MyD88-dependent and -independent signalling via TLR3 and TLR4 are differentially modulated by Δ 9-tetrahydrocannabinol and cannabidiol in human macrophages. J Neuroimmunol 2020; 343:577217. [PMID: 32244040 DOI: 10.1016/j.jneuroim.2020.577217] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 03/12/2020] [Accepted: 03/18/2020] [Indexed: 12/17/2022]
Abstract
Toll-like receptors (TLRs) are sensors of pathogen-associated molecules that trigger inflammatory signalling in innate immune cells including macrophages. All TLRs, with the exception of TLR3, promote intracellular signalling via recruitment of the myeloid differentiation factor 88 (MyD88) adaptor, while TLR3 signals via Toll-Interleukin-1 Receptor (TIR)-domain-containing adaptor-inducing interferon (IFN)-β (TRIF) adaptor to induce MyD88-independent signalling. Furthermore, TLR4 can activate both MyD88-dependent and -independent signalling (via TRIF). The study aim was to decipher the impact of the highly purified plant-derived (phyto) cannabinoids Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), when delivered in isolation and in combination (1:1), on MyD88-dependent and -independent signalling in macrophages. We employed the use of the viral dsRNA mimetic poly(I:C) and endotoxin lipopolysaccharide (LPS), to induce viral TLR3 and bacterial TLR4 signalling in human Tamm-Horsfall protein-1 (THP-1)-derived macrophages, respectively. TLR3/TLR4 stimulation promoted the activation of interferon (IFN) regulatory factor 3 (IRF3) and TLR4 promoted the activation of nuclear factor (NF)-κB signalling, with downstream production of the type I IFN-β, the chemokines CXCL10 and CXCL8, and cytokine TNF-α. THC and CBD (both at 10 μM) attenuated TLR3/4-induced IRF3 activation and induction of CXCL10/IFN-β, while both phytocannabinoids failed to impact TLR4-induced IκB-α degradation and TNF-α/CXCL8 expression. The role of CB1, CB2 and PPARγ receptors in mediating the effect of THC and CBD on MyD88-independent signalling was investigated. TLRs are attractive therapeutic targets given their role in inflammation and initiation of adaptive immunity, and data herein indicate that both CBD and THC preferentially modulate TLR3 and TLR4 signalling via MyD88-independent mechanisms in macrophages. This offers mechanistic insight into the role of phytocannabinoids in modulating cellular inflammation.
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Affiliation(s)
- John-Mark Fitzpatrick
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Eleanor Minogue
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Lucy Curham
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Harry Tyrrell
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - Philip Gavigan
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland
| | - William Hind
- GW Research Ltd, Sovereign House, Vision Park, Histon, CB24 9BZ, United Kingdom
| | - Eric J Downer
- Discipline of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, University of Dublin, Dublin, Ireland.
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13
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Hughes EM, Calcagno P, Clarke M, Sanchez C, Smith K, Kelly JP, Finn DP, Roche M. Prenatal exposure to valproic acid reduces social responses and alters mRNA levels of opioid receptor and pre-pro-peptide in discrete brain regions of adolescent and adult male rats. Brain Res 2020; 1732:146675. [PMID: 31978376 DOI: 10.1016/j.brainres.2020.146675] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 01/15/2020] [Accepted: 01/17/2020] [Indexed: 12/21/2022]
Abstract
Altered social behaviours are a hallmark of several psychiatric and developmental disorders. Clinical and preclinical data have demonstrated that prenatal exposure to valproic acid (VPA), an anti-epileptic and mood stabiliser, is associated with impaired social responses, and thus provides a useful model for the evaluation of neurobiological mechanisms underlying altered social behaviours. The opioid system is widely recognised to regulate and modulate social behaviours, however few studies have examined if the endogenous opioid system is altered in animal models of social impairment. The present study examined social behavioural responses of adolescent and adult male rats prenatally exposed to VPA, and the expression of mRNA encoding opioid receptors and pre-pro-peptides in discrete brain regions. Adolescent and adult rats prenatally exposed to VPA spent less time engaging in social behaviours in the direct social interaction test and exhibited reduced sociability and social novelty preference in the 3-chamber sociability test, compared to saline-treated counterparts. The VPA-exposed adolescent rats exhibited significantly reduced kappa opioid receptor (oprk1) and pre-pro-dynorphin (pdyn) mRNA expression in the cerebral cortex, and reduced oprk1 and nociceptin/orphanin FQ (oprl1) mRNA expression in the hypothalamus. Adult rats prenatally exposed to VPA exhibited decreased mRNA expression of oprk1 and pdyn in hypothalamus, reduced pro-opiomelanocortin(pomc) in the striatum and an increase in delta opioid receptor (oprd1) mRNA in the amygdaloid cortex, when compared to saline-treated counterparts. Mu opioid receptor (oprm1) mRNA expression did not differ between saline and VPA-exposed rats in any region examined. The data demonstrate that impaired social behaviours in adolescent and adult rats prenatally exposed to VPA is accompanied by altered mRNA expression of opioid receptors and pre-pro-peptides in a region specific manner. In particular, both adolescent and adult VPA-exposed rats exhibit reduced oprk1-pdyn mRNA expression in several brain regions, which are associated with deficits in social behavioural responding in the model.
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Affiliation(s)
- Edel M Hughes
- Physiology, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland; Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - Patricia Calcagno
- Physiology, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland; Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland
| | - Morgane Clarke
- Physiology, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland; Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland
| | | | | | - John P Kelly
- Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland; Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - David P Finn
- Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland; Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - Michelle Roche
- Physiology, School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland; Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland.
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14
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Hu J, Wang W, Hao Q, Zhang T, Yin H, Wang M, Zhang C, Zhang C, Zhang L, Zhang X, Wang W, Cao X, Xiang J, Ye X. Suppressors of cytokine signalling (SOCS)-1 inhibits neuroinflammation by regulating ROS and TLR4 in BV2 cells. Inflamm Res 2020; 69:27-39. [PMID: 31707448 DOI: 10.1007/s00011-019-01289-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 09/26/2019] [Accepted: 09/30/2019] [Indexed: 02/01/2023] Open
Abstract
OBJECTIVE The suppressors of cytokine signaling (SOCS) proteins are physiological suppressors of cytokine signaling which have been identified as a negative feedback loop to weaken cytokine signaling. However, the underlying molecular mechanisms is unknown. This study was to investigate the role of SOCS1 in the oxygen-glucose deprivation and reoxygenation (OGDR) or LPS-induced inflammation in microglia cell line BV-2 cells. MATERIALS AND METHODS BV-2 microglial cells were used to construct inflammation model. A SOCS1 over-expression plasmid was constructed, and the SOCS1-deficient cells were generated by utilizing the CRISPR/CAS9 system. BV-2 microglial cells were pretreated with over-expression plasmid or SOCS1 CRISPR plasmid before OGDR and LPS stimulation. The effect of SOCS1 on proinflammatory cytokines, toll-like receptor 4 (TLR4), and reactive oxygen species (ROS) were evaluated. RESULTS We found that SOCS1 increased in OGDR or LPS-treated BV-2 microglial cells in vitro. SOCS1 over-expression significantly reduced the production of proinflammatory cytokines including tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and IL-6, and CRISPR/CAS9-mediated SOCS1 knockout reversed this effect. Also we determined that SOCS1 over-expression reduced the level of reactive oxygen species (ROS) while the absence of SOCS1 increased the production of ROS after OGDR or LPS-stimulated inflammation. Furthermore, we found that OGDR and LPS induced the expression of toll-like receptor 4 (TLR4) in BV2 cells. Nevertheless, SOCS1 over-expression attenuated the expression of TLR4, while knockdown of SOCS1 upregulated TLR4. CONCLUSIONS Our study indicated that SOCS1 played a protective role under inflammatory conditions in OGDR or LPS treated BV-2 cells through regulating ROS and TLR4. These data demonstrated that SOCS1 served as a potential therapeutic target to alleviate inflammation after ischemic stroke.
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Affiliation(s)
- Jinxia Hu
- Institute of Stroke Center, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China.,School of Material Science and Engineering, China University of Mining and Technology, Xuzhou, 221116, Jiangsu, People's Republic of China
| | - Weiwei Wang
- Department of Rehabilitation Medicine, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, No. 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, People's Republic of China.,Department of Rehabilitation Medicine, Linyi Cancer Hospital, Linyi, 276001, Shandong, People's Republic of China
| | - Qi Hao
- Institute of Stroke Center, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China
| | - Tao Zhang
- Institute of Stroke Center, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China
| | - Hanhan Yin
- Institute of Stroke Center, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China
| | - Miao Wang
- Institute of Stroke Center, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China
| | - Cheng Zhang
- Institute of Stroke Center, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China
| | - Conghui Zhang
- Institute of Stroke Center, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China
| | - Lijie Zhang
- Department of Rehabilitation Medicine, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, No. 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, People's Republic of China
| | - Xiao Zhang
- Department of Rehabilitation Medicine, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, No. 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, People's Republic of China
| | - Wei Wang
- Department of Rehabilitation Medicine, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, No. 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, People's Republic of China
| | - Xichuan Cao
- School of Material Science and Engineering, China University of Mining and Technology, Xuzhou, 221116, Jiangsu, People's Republic of China
| | - Jie Xiang
- Department of Rehabilitation Medicine, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, No. 99 West Huaihai Road, Xuzhou, 221006, Jiangsu, People's Republic of China.
| | - Xinchun Ye
- Institute of Stroke Center, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China.
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15
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Fitzgibbon M, Kerr DM, Henry RJ, Finn DP, Roche M. Endocannabinoid modulation of inflammatory hyperalgesia in the IFN-α mouse model of depression. Brain Behav Immun 2019; 82:372-381. [PMID: 31505257 DOI: 10.1016/j.bbi.2019.09.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 08/15/2019] [Accepted: 09/05/2019] [Indexed: 12/31/2022] Open
Abstract
Depression is a well-recognised effect of long-term treatment with interferon-alpha (IFN-α), a widely used treatment for chronic viral hepatitis and malignancy. In addition to the emotional disturbances, high incidences of painful symptoms such as headache and joint pain have also been reported following IFN-α treatment. The endocannabinoid system plays an important role in emotional and nociceptive processing, however it is unknown whether repeated IFN-α administration induces alterations in this system. The present study investigated nociceptive responding in the IFN-α-induced mouse model of depression and associated changes in the endocannabinoid system. Furthermore, the effects of modulating peripheral endocannabinoid tone on inflammatory pain-related behaviour in the IFN-α model was examined. Repeated IFN-α administration (8000 IU/g/day) to male C57/Bl6 mice increased immobility in the forced swim test and reduced sucrose preference, without altering body weight gain or locomotor activity, confirming development of the depressive-like phenotype. There was no effect of repeated IFN-α administration on latency to respond in the hot plate test on day 4 or 7 of treatment, however, formalin-evoked nociceptive behaviour was significantly increased in IFN-α treated mice following 8 days of IFN-α administration. 2-Arachidonoyl glycerol (2-AG) levels in the periaqueductal grey (PAG) and rostroventromedial medulla (RVM), and anandamide (AEA) levels in the RVM, were significantly increased in IFN-α-, but not saline-, treated mice following formalin administration. There was no change in endocannabinoid levels in the prefrontal cortex, spinal cord or paw tissue between saline- or IFNα-treated mice in the presence or absence of formalin. Furthermore, repeated IFN-α and/or formalin administration did not alter mRNA expression of genes encoding the endocannabinoid catabolic enzymes (fatty acid amide hydrolase or monoacylglycerol lipase) or endocannabinoid receptor targets (CB1, CB2 or PPARs) in the brain, spinal cord or paw tissue. Intra plantar administration of PF3845 (1 μg/10 μl) or MJN110 (1 μg/10 μl), inhibitors of AEA and 2-AG catabolism respectively, attenuated formalin-evoked hyperalgesia in IFN-α, but not saline-, treated mice. In summary, increasing peripheral endocannabinoid tone attenuates inflammatory hyperalgesia induced following repeated IFN-α administration. These data provide support for the endocannabinoid system in mediating and modulating heightened pain responding associated with IFNα-induced depression.
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Affiliation(s)
- Marie Fitzgibbon
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland
| | - Daniel M Kerr
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland; Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, Ireland
| | - Rebecca J Henry
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland
| | - David P Finn
- Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, Ireland; NCBES Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - Michelle Roche
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland; NCBES Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland.
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16
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He L, Xu R, Chen Y, Liu X, Pan Y, Cao S, Xu T, Tian H, Zeng J. Intra-CA1 Administration of Minocycline Alters the Expression of Inflammation-Related Genes in Hippocampus of CCI Rats. Front Mol Neurosci 2019; 12:248. [PMID: 31708740 PMCID: PMC6822549 DOI: 10.3389/fnmol.2019.00248] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 09/26/2019] [Indexed: 11/13/2022] Open
Affiliation(s)
- Li He
- Department of Physiology, Zunyi Medical University, Zunyi, China
| | - Rui Xu
- Department of Physiology, Zunyi Medical University, Zunyi, China
| | - Yuanshou Chen
- Department of Physiology, Zunyi Medical University, Zunyi, China
| | - Xiaohong Liu
- Department of Physiology, Zunyi Medical University, Zunyi, China
| | - Youfu Pan
- Department of Genetics, Zunyi Medical University, Zunyi, China
| | - Song Cao
- Department of Pain Medicine, Affiliated Hospital of Zunyi Medical Univerisity, Zunyi, China
| | - Tao Xu
- Department of Physiology, Zunyi Medical University, Zunyi, China
| | - Hong Tian
- Department of Physiology, Zunyi Medical University, Zunyi, China
| | - Junwei Zeng
- Department of Physiology, Zunyi Medical University, Zunyi, China
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17
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Paloczi J, Varga ZV, Hasko G, Pacher P. Neuroprotection in Oxidative Stress-Related Neurodegenerative Diseases: Role of Endocannabinoid System Modulation. Antioxid Redox Signal 2018; 29:75-108. [PMID: 28497982 PMCID: PMC5984569 DOI: 10.1089/ars.2017.7144] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
SIGNIFICANCE Redox imbalance may lead to overproduction of reactive oxygen and nitrogen species (ROS/RNS) and subsequent oxidative tissue damage, which is a critical event in the course of neurodegenerative diseases. It is still not fully elucidated, however, whether oxidative stress is the primary trigger or a consequence in the process of neurodegeneration. Recent Advances: Increasing evidence suggests that oxidative stress is involved in the propagation of neuronal injury and consequent inflammatory response, which in concert promote development of pathological alterations characteristic of most common neurodegenerative diseases. CRITICAL ISSUES Accumulating recent evidence also suggests that there is an important interplay between the lipid endocannabinoid system [ECS; comprising the main cannabinoid 1 and 2 receptors (CB1 and CB2), endocannabinoids, and their synthetic and metabolizing enzymes] and various key inflammatory and redox-dependent processes. FUTURE DIRECTIONS Targeting the ECS to modulate redox state-dependent cell death and to decrease consequent or preceding inflammatory response holds therapeutic potential in a multitude of oxidative stress-related acute or chronic neurodegenerative disorders from stroke and traumatic brain injury to Alzheimer's and Parkinson's diseases and multiple sclerosis, just to name a few, which will be discussed in this overview. Antioxid. Redox Signal. 29, 75-108.
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Affiliation(s)
- Janos Paloczi
- 1 Laboratory of Cardiovascular Physiology and Tissue Injury (LCPTI), National Institute on Alcohol Abuse and Alcoholism (NIAAA), National Institutes of Health (NIH) , Bethesda, Maryland
| | - Zoltan V Varga
- 1 Laboratory of Cardiovascular Physiology and Tissue Injury (LCPTI), National Institute on Alcohol Abuse and Alcoholism (NIAAA), National Institutes of Health (NIH) , Bethesda, Maryland
| | - George Hasko
- 2 Department of Surgery, Rutgers New Jersey Medical School , Newark, New Jersey
| | - Pal Pacher
- 1 Laboratory of Cardiovascular Physiology and Tissue Injury (LCPTI), National Institute on Alcohol Abuse and Alcoholism (NIAAA), National Institutes of Health (NIH) , Bethesda, Maryland
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18
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Flannery LE, Kerr DM, Finn DP, Roche M. FAAH inhibition attenuates TLR3-mediated hyperthermia, nociceptive- and anxiety-like behaviour in female rats. Behav Brain Res 2018; 353:11-20. [PMID: 29953903 DOI: 10.1016/j.bbr.2018.06.030] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 05/21/2018] [Accepted: 06/25/2018] [Indexed: 01/09/2023]
Abstract
Aberrant activation of toll-like receptor (TLR)s results in persistent and prolonged neuroinflammation and has been implicated in the pathogenesis and exacerbation of psychiatric and neurodegenerative disorders. TLR3 coordinates the innate immune response to viral infection and recent data have demonstrated that inhibiting fatty acid amide hydrolase (FAAH), the enzyme that primarily metabolizes anandamide, modulates TLR3-mediated neuroinflammation. However, the physiological and behavioural consequences of such modulation are unknown. The present study examined the effect of URB597, a selective FAAH inhibitor, on neuroinflammation, physiological and behavioural alterations following administration of the TLR3 agonist and viral mimetic poly I:C to female rats. URB597 attenuated TLR3-mediated fever, mechanical and cold allodynia, and anxiety-like behaviour in the elevated plus maze and open field arena. There was no effect of URB597 on TLR3-mediated decreases in body weight and no effect in the sucrose preference or forced swim tests. URB597 attenuated the TLR3-mediated increase in the expression of CD11b and CD68, markers of microglia/macrophage activation. In summary, these data demonstrate that enhancing FAAH substrate levels suppresses TLR3-mediated microglia/macrophage activation and associated changes in fever, nociceptive responding and anxiety-related behaviour. These data provide further support for FAAH as a novel therapeutic target for neuroinflammatory disorders.
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Affiliation(s)
- Lisa E Flannery
- Physiology, School of Medicine, National University of Ireland Galway, Ireland; NCBES Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland Galway, Ireland
| | - Daniel M Kerr
- Physiology, School of Medicine, National University of Ireland Galway, Ireland; Pharmacology and Therapeutics, School of Medicine, National University of Ireland Galway, Ireland; NCBES Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland Galway, Ireland
| | - David P Finn
- Pharmacology and Therapeutics, School of Medicine, National University of Ireland Galway, Ireland; NCBES Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland Galway, Ireland
| | - Michelle Roche
- Physiology, School of Medicine, National University of Ireland Galway, Ireland; NCBES Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland Galway, Ireland.
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19
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Holzer P, Farzi A, Hassan AM, Zenz G, Jačan A, Reichmann F. Visceral Inflammation and Immune Activation Stress the Brain. Front Immunol 2017; 8:1613. [PMID: 29213271 PMCID: PMC5702648 DOI: 10.3389/fimmu.2017.01613] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Accepted: 11/07/2017] [Indexed: 12/20/2022] Open
Abstract
Stress refers to a dynamic process in which the homeostasis of an organism is challenged, the outcome depending on the type, severity, and duration of stressors involved, the stress responses triggered, and the stress resilience of the organism. Importantly, the relationship between stress and the immune system is bidirectional, as not only stressors have an impact on immune function, but alterations in immune function themselves can elicit stress responses. Such bidirectional interactions have been prominently identified to occur in the gastrointestinal tract in which there is a close cross-talk between the gut microbiota and the local immune system, governed by the permeability of the intestinal mucosa. External stressors disturb the homeostasis between microbiota and gut, these disturbances being signaled to the brain via multiple communication pathways constituting the gut-brain axis, ultimately eliciting stress responses and perturbations of brain function. In view of these relationships, the present article sets out to highlight some of the interactions between peripheral immune activation, especially in the visceral system, and brain function, behavior, and stress coping. These issues are exemplified by the way through which the intestinal microbiota as well as microbe-associated molecular patterns including lipopolysaccharide communicate with the immune system and brain, and the mechanisms whereby overt inflammation in the GI tract impacts on emotional-affective behavior, pain sensitivity, and stress coping. The interactions between the peripheral immune system and the brain take place along the gut-brain axis, the major communication pathways of which comprise microbial metabolites, gut hormones, immune mediators, and sensory neurons. Through these signaling systems, several transmitter and neuropeptide systems within the brain are altered under conditions of peripheral immune stress, enabling adaptive processes related to stress coping and resilience to take place. These aspects of the impact of immune stress on molecular and behavioral processes in the brain have a bearing on several disturbances of mental health and highlight novel opportunities of therapeutic intervention.
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Affiliation(s)
- Peter Holzer
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Graz, Austria.,BioTechMed-Graz, Graz, Austria
| | - Aitak Farzi
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Graz, Austria
| | - Ahmed M Hassan
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Graz, Austria
| | - Geraldine Zenz
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Graz, Austria
| | - Angela Jačan
- CBmed GmbH-Center for Biomarker Research in Medicine, Graz, Austria
| | - Florian Reichmann
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Graz, Austria
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20
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Zhao X, Liang P, Liu J, Jiang H, Fan X, Chen G, Zhou C. Elevation of arachidonoylethanolamide levels by activation of the endocannabinoid system protects against colitis and ameliorates remote organ lesions in mice. Exp Ther Med 2017; 14:5664-5670. [PMID: 29285108 DOI: 10.3892/etm.2017.5222] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 06/29/2017] [Indexed: 02/07/2023] Open
Abstract
The endocannabinoid system (ECS) is a potential pharmaceutical target for the treatment of inflammatory bowel diseases (IBDs). The aim of this study was to explore the effects of activation of the ECS on IBD and the associated neural inflammation-induced disruption of the blood-brain barrier (BBB). In a mouse model of trinitrobenzene sulfonic acid-induced colitis, the inhibition of fatty acid amide hydrolase with URB597 elevated the arachidonoylethanolamide concentration of the colon. Macroscopic alterations of the colons were evaluated, and the 7-day survival rate of mice was analyzed. BBB integrity was assessed using a dye tracer method, and the cognitive function of mice was examined using a fear-conditioning test. URB597 treatment significantly reduced macroscopic alterations of the colon, decreased the mortality rate, and protected the integrity of the BBB in the mice (P<0.05). No significant changes were observed in the cognitive functions of the mice (P>0.05); therefore, the neuroprotective effect of ECS in this colitis model requires further investigation. Activation of the ECS was efficient in ameliorating colitis and increasing the survival rate of the mice, and reducing remote organ changes induced by colitis. The results suggest that modulation of the ECS is a potential therapeutic approach for IBDs and the associated remote organ lesions.
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Affiliation(s)
- Xiaolin Zhao
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,West China School of Pharmacy, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Peng Liang
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Jin Liu
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Haixia Jiang
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Anesthesiology, The First Affiliated Hospital of Kunming Medical University, Yunnan, Kunming 650221, P.R. China
| | - Xiaoshuai Fan
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Guo Chen
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Cheng Zhou
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
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21
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Flannery LE, Henry RJ, Kerr DM, Finn DP, Roche M. FAAH, but not MAGL, inhibition modulates acute TLR3-induced neuroimmune signaling in the rat, independent of sex. J Neurosci Res 2017; 96:989-1001. [PMID: 28726298 DOI: 10.1002/jnr.24120] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 06/16/2017] [Accepted: 06/28/2017] [Indexed: 12/12/2022]
Abstract
Toll-like receptor (TLR)3 is a key component of the innate immune response to viral infection. The present study firstly examined whether sex differences exist in TLR3-induced inflammatory, endocrine, and sickness responses. The data revealed that TLR3-induced expression of interferon- or NFkB-inducible genes (IFN-α/β, IP-10, or TNF-α), either peripherally (spleen) or centrally (hypothalamus), did not differ between male and female rats, with the exception of TLR3-induced IFN-α expression in the spleen of female, but not male, rats 8 hr post TLR3 activation. Furthermore, TLR3 activation increased plasma corticosterone levels, induced fever, and reduced locomotor activity and body weight - effects independent of sex. Thus, the acute-phase inflammatory, endocrine, and sickness responses to TLR3 activation exhibit minimal sex-related differences. A further aim of this study was to examine whether enhancing endocannabinoid tone - namely, 2-arachidonylglycerol (2-AG) or N-arachidonoylethanolamine (AEA), exhibited similar effects on TLR3-induced inflammatory responses in male versus female rats. Systemic administration of the monoacylglycerol lipase (MAGL) inhibitor MJN110 and subsequent increases in 2-AG levels did not alter the TLR3-induced increase in IP-10, IRF7, or TNF-α expression in the spleen or the hypothalamus of male or female rats. In contrast, the fatty acid amide hydrolase (FAAH) inhibitor URB597 increased levels of AEA and related N-acylethanolamines, an effect associated with the attenuation of TLR3-induced inflammatory responses in the hypothalamus, but not the spleen, of male and female rats. These data support a role for FAAH, but not MAGL, substrates in the modulation of TLR3-induced neuroinflammatory responses, effects independent of sex.
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Affiliation(s)
- Lisa E Flannery
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland
- NCBES Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - Rebecca J Henry
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland
- NCBES Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - Daniel M Kerr
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland
- NCBES Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
- Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, Ireland
| | - David P Finn
- NCBES Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
- Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, Ireland
| | - Michelle Roche
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland
- NCBES Centre for Pain Research and Galway Neuroscience Centre, National University of Ireland, Galway, Ireland
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22
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Pharmacological inhibition of FAAH modulates TLR-induced neuroinflammation, but not sickness behaviour: An effect partially mediated by central TRPV1. Brain Behav Immun 2017; 62:318-331. [PMID: 28237711 DOI: 10.1016/j.bbi.2017.02.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 02/17/2017] [Accepted: 02/19/2017] [Indexed: 01/08/2023] Open
Abstract
Aberrant activation of toll-like receptors (TLRs), key components of the innate immune system, has been proposed to underlie and exacerbate a range of central nervous system disorders. Increasing evidence supports a role for the endocannabinoid system in modulating inflammatory responses including those mediated by TLRs, and thus this system may provide an important treatment target for neuroinflammatory disorders. However, the effect of modulating endocannabinoid tone on TLR-induced neuroinflammation in vivo and associated behavioural changes is largely unknown. The present study examined the effect of inhibiting fatty acid amide hydrolyase (FAAH), the primary enzyme responsible for the metabolism of anandamide (AEA), in vivo on TLR4-induced neuroimmune and behavioural responses, and evaluated sites and mechanisms of action. Systemic administration of the FAAH inhibitor PF3845 increased levels of AEA, and related FAAH substrates N-oleoylethanolamide (OEA) and N-palmitoylethanolamide (PEA), in the frontal cortex and hippocampus of rats, an effect associated with an attenuation in the expression of pro- and anti-inflammatory cytokines and mediators measured 2hrs following systemic administration of the TLR4 agonist, lipopolysaccharide (LPS). These effects were mimicked by central i.c.v. administration of PF3845, but not systemic administration of the peripherally-restricted FAAH inhibitor URB937. Central antagonism of TRPV1 significantly attenuated the PF3845-induced decrease in IL-6 expression, effects not observed following antagonism of CB1, CB2, PPARα, PPARγ or GPR55. LPS-induced a robust sickness-like behavioural response and increased the expression of markers of glial activity and pro-inflammatory cytokines over 24hrs. Systemic administration of PF3845 modulated the TLR4-induced expression of neuroimmune mediators and anhedonia without altering acute sickness behaviour. Overall, these findings support an important role for FAAH substrates directly within the brain in the regulation of TLR4-associated neuroinflammation and highlight a role for TRPV1 in partially mediating these effects.
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23
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Zhang T, Sun K, Shen W, Qi L, Yin W, Wang LW. SOCS1 regulates neuropathic pain by inhibiting neuronal sensitization and glial activation in mouse spinal cord. Brain Res Bull 2016; 124:231-7. [PMID: 27233783 DOI: 10.1016/j.brainresbull.2016.05.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 05/20/2016] [Accepted: 05/22/2016] [Indexed: 02/08/2023]
Abstract
Neuropathic pain is still a basic science and clinical challenge now, the neuronal sensitization and glial activation in the spinal cord (SC) level are more far-reaching for contributing to pain hypersensitivity following chronic constriction injury (CCI). Accumulating evidence indicates that astrocytes and microglia are activated in the spinal cord dorsal horn (SCDH) after CCI. Suppressor of cytokine signaling 1 (SOCS1) plays an important role in regulating of neuronal inflammation. Here, we investigated the role of SOCS1 in SC played in neuropathic pain. We find SOCS1 was persistently downregulated in the spinal neurons after CCI in mice. On the contrary, overexpression of SOCS1 in the SC reversed CCI-induced pain behavioral, activation of neurons, astrocytes, microglia, and the expression of proinflammatory cytokines including tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β) and IL-6. Over all, these results demonstrate that downregulation of SOCS1 contributed to the development and maintenance of neuropathic pain via activating of neurons, astrocytes, microglia, and proinflammatory cytokines. SOCS1 may be developed into a potential target for treating neuropathic pain.
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Affiliation(s)
- Ting Zhang
- Department of Pain Medicine, Xuzhou Central Hospital, Xuzhou, Jiangsu 221004, China
| | - Kai Sun
- Department of Pain Medicine, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221004, China
| | - Wen Shen
- Department of Pain Medicine, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221004, China
| | - Le Qi
- Department of Pain Medicine, Xuzhou Central Hospital, Xuzhou, Jiangsu 221004, China
| | - Wei Yin
- Department of Pain Medicine, Xuzhou Central Hospital, Xuzhou, Jiangsu 221004, China
| | - Li-Wei Wang
- Department of Pain Medicine, Xuzhou Central Hospital, Xuzhou, Jiangsu 221004, China.
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24
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Albrecht DS, Granziera C, Hooker JM, Loggia ML. In Vivo Imaging of Human Neuroinflammation. ACS Chem Neurosci 2016; 7:470-83. [PMID: 26985861 DOI: 10.1021/acschemneuro.6b00056] [Citation(s) in RCA: 133] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Neuroinflammation is implicated in the pathophysiology of a growing number of human disorders, including multiple sclerosis, chronic pain, traumatic brain injury, and amyotrophic lateral sclerosis. As a result, interest in the development of novel methods to investigate neuroinflammatory processes, for the purpose of diagnosis, development of new therapies, and treatment monitoring, has surged over the past 15 years. Neuroimaging offers a wide array of non- or minimally invasive techniques to characterize neuroinflammatory processes. The intent of this Review is to provide brief descriptions of currently available neuroimaging methods to image neuroinflammation in the human central nervous system (CNS) in vivo. Specifically, because of the relatively widespread accessibility of equipment for nuclear imaging (positron emission tomography [PET]; single photon emission computed tomography [SPECT]) and magnetic resonance imaging (MRI), we will focus on strategies utilizing these technologies. We first provide a working definition of "neuroinflammation" and then discuss available neuroimaging methods to study human neuroinflammatory processes. Specifically, we will focus on neuroimaging methods that target (1) the activation of CNS immunocompetent cells (e.g. imaging of glial activation with TSPO tracer [(11)C]PBR28), (2) compromised BBB (e.g. identification of MS lesions with gadolinium-enhanced MRI), (3) CNS-infiltration of circulating immune cells (e.g. tracking monocyte infiltration into brain parenchyma with iron oxide nanoparticles and MRI), and (4) pathological consequences of neuroinflammation (e.g. imaging apoptosis with [(99m)Tc]Annexin V or iron accumulation with T2* relaxometry). This Review provides an overview of state-of-the-art techniques for imaging human neuroinflammation which have potential to impact patient care in the foreseeable future.
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Affiliation(s)
| | - Cristina Granziera
- Neuro-Immunology,
Neurology Division, Department of Clinical Neurosciences, Centre Hospitalier
Universitaire Vaudois and University of Lausanne, CH-1011 Lausanne, Switzerland
- LTS5, Ecole
Polytechnique
Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
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25
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Fitzpatrick JMK, Downer EJ. Toll-like receptor signalling as a cannabinoid target in Multiple Sclerosis. Neuropharmacology 2016; 113:618-626. [PMID: 27079840 DOI: 10.1016/j.neuropharm.2016.04.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 01/20/2016] [Accepted: 04/08/2016] [Indexed: 02/06/2023]
Abstract
Toll-like receptors (TLRs) are the sensors of pathogen-associated molecules that trigger tailored innate immune intracellular signalling responses to initiate innate immune reactions. Data from the experimental autoimmune encephalomyelitis (EAE) model indicates that TLR signalling machinery is a pivotal player in the development of murine EAE. To compound this, data from human studies indicate that complex interplay exists between TLR signalling and Multiple Sclerosis (MS) pathogenesis. Cannabis-based therapies are in clinical development for the management of a variety of medical conditions, including MS. In particular Sativex®, a combination of plant-derived cannabinoids, is an oromucosal spray with efficacy in MS patients, particularly those with neuropathic pain and spasticity. Despite this, the precise cellular and molecular mechanisms of action of Sativex® in MS patients remains unclear. This review will highlight evidence that novel interplay exists between the TLR and cannabinoid systems, both centrally and peripherally, with relevance to the pathogenesis of MS. This article is part of the Special Issue entitled 'Lipid Sensing G Protein-Coupled Receptors in the CNS'.
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Affiliation(s)
- John-Mark K Fitzpatrick
- Department of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, University of Dublin, Trinity College, Dublin 2, Ireland
| | - Eric J Downer
- Department of Physiology, School of Medicine, Trinity Biomedical Sciences Institute, University of Dublin, Trinity College, Dublin 2, Ireland.
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26
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Dyall SC, Mandhair HK, Fincham REA, Kerr DM, Roche M, Molina-Holgado F. Distinctive effects of eicosapentaenoic and docosahexaenoic acids in regulating neural stem cell fate are mediated via endocannabinoid signalling pathways. Neuropharmacology 2016; 107:387-395. [PMID: 27044662 DOI: 10.1016/j.neuropharm.2016.03.055] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 03/30/2016] [Accepted: 03/31/2016] [Indexed: 11/29/2022]
Abstract
Emerging evidence suggests a complex interplay between the endocannabinoid system, omega-3 fatty acids and the immune system in the promotion of brain self-repair. However, it is unknown if all omega-3 fatty acids elicit similar effects on adult neurogenesis and if such effects are mediated or regulated by interactions with the endocannabinoid system. This study investigated the effects of DHA and EPA on neural stem cell (NSC) fate and the role of the endocannabinoid signalling pathways in these effects. EPA, but not DHA, significantly increased proliferation of NSCs compared to controls, an effect associated with enhanced levels of the endocannabinoid 2-arachidonylglycerol (2-AG) and p-p38 MAPK, effects attenuated by pre-treatment with CB1 (AM251) or CB2 (AM630) receptor antagonists. Furthermore, in NSCs derived from IL-1β deficient mice, EPA significantly decreased proliferation and p-p38 MAPK levels compared to controls, suggesting a key role for IL-1β signalling in the effects observed. Although DHA similarly increased 2-AG levels in wild-type NSCs, there was no concomitant increase in proliferation or p-p38 MAPK activity. In addition, in NSCs from IL-1β deficient mice, DHA significantly increased proliferation without effects on p-P38 MAPK, suggesting effects of DHA are mediated via alternative signalling pathways. These results provide crucial new insights into the divergent effects of EPA and DHA in regulating NSC proliferation and the pathways involved, and highlight the therapeutic potential of their interplay with endocannabinoid signalling in brain repair.
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Affiliation(s)
- S C Dyall
- Department of Life Sciences, University of Roehampton, Whitelands College, London, UK; Faculty of Health and Social Sciences, Bournemouth University, Dorset, UK.
| | - H K Mandhair
- Department of Life Sciences, University of Roehampton, Whitelands College, London, UK
| | - R E A Fincham
- Department of Life Sciences, University of Roehampton, Whitelands College, London, UK
| | - D M Kerr
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland; Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, Ireland; NCBES Centre for Pain Research and Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - M Roche
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland; NCBES Centre for Pain Research and Neuroscience Centre, National University of Ireland, Galway, Ireland
| | - F Molina-Holgado
- Department of Life Sciences, University of Roehampton, Whitelands College, London, UK
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27
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Richter F, Koulen P, Kaja S. N-Palmitoylethanolamine Prevents the Run-down of Amplitudes in Cortical Spreading Depression Possibly Implicating Proinflammatory Cytokine Release. Sci Rep 2016; 6:23481. [PMID: 27004851 PMCID: PMC4804239 DOI: 10.1038/srep23481] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 03/08/2016] [Indexed: 02/07/2023] Open
Abstract
Cortical spreading depression (CSD), a wave of neuronal depolarization in the cerebral cortex following traumatic brain injury or cerebral ischemia, significantly aggravates brain damage. Here, we tested whether N-palmitoylethanolamine (PEA), a substance that effectively reduces lesion volumes and neurological deficits after ischemic stroke, influences CSD. CSD was elicited chemically in adult rats and occurrence, amplitude, duration and propagation velocity of CSD was determined prior to and for 6 hours after intraperitoneal injection of PEA. The chosen systemic administration of PEA stabilized the amplitude of CSD for at least four hours and prevented the run-down of amplitudes that is typically observed and was also seen in untreated controls. The propagation velocity of the CSD waves was unaltered indicating stable neuronal excitability. The stabilization of CSD amplitudes by PEA indicates that inhibition or prevention of CSD does not underlie PEA's profound neuroprotective effect. Rather, PEA likely inhibits proinflammatory cytokine release thereby preventing the run-down of CSD amplitudes. This contribution of PEA to the maintenance of neuronal excitability in healthy tissue during CSD potentially adds to neuroprotection outside a damaged area, while other mechanisms control PEA-mediated neuroprotection in damaged tissue resulting from traumatic brain injury or cerebral ischemia.
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Affiliation(s)
- Frank Richter
- Institute of Physiology I/Neurophysiology, Jena University Hospital-Friedrich Schiller University Jena, Jena, Germany
| | - Peter Koulen
- Vision Research Center, Department of Ophthalmology, University of Missouri – Kansas City, School of Medicine, 2411 Holmes St., Kansas City, MO 64108, USA
- Department of Basic Medical Science, University of Missouri – Kansas City, School of Medicine, 2411 Holmes St., Kansas City, MO 64108, USA
| | - Simon Kaja
- Vision Research Center, Department of Ophthalmology, University of Missouri – Kansas City, School of Medicine, 2411 Holmes St., Kansas City, MO 64108, USA
- Departments of Ophthalmology and Molecular Pharmacology and Therapeutics, Loyola University Chicago, Stritch School of Medicine, 2160 South First Ave., Maywood, IL 60153, USA
- Edward Hines Jr. VA Hospital, Research Service, 5000 S Fifth Ave., Hines, IL 60141, USA
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28
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Henry RJ, Kerr DM, Finn DP, Roche M. For whom the endocannabinoid tolls: Modulation of innate immune function and implications for psychiatric disorders. Prog Neuropsychopharmacol Biol Psychiatry 2016; 64:167-80. [PMID: 25794989 DOI: 10.1016/j.pnpbp.2015.03.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 03/03/2015] [Accepted: 03/03/2015] [Indexed: 12/21/2022]
Abstract
Toll-like receptors (TLRs) mediate the innate immune response to pathogens and are critical in the host defence, homeostasis and response to injury. However, uncontrolled and aberrant TLR activation can elicit potent effects on neurotransmission and neurodegenerative cascades and has been proposed to trigger the onset of certain neurodegenerative disorders and elicit detrimental effects on the progression and outcome of established disease. Over the past decade, there has been increasing evidence demonstrating that the endocannabinoid system can elicit potent modulatory effects on inflammatory processes, with clinical and preclinical evidence demonstrating beneficial effects on disease severity and symptoms in several inflammatory conditions. This review examines the evidence supporting a modulatory effect of endocannabinoids on TLR-mediated immune responses both peripherally and centrally, and the implications for psychiatric disorders such as depression and schizophrenia.
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Affiliation(s)
- Rebecca J Henry
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland; Galway Neuroscience Centre and Centre for Pain Research, NCBES, National University of Ireland, Galway, Ireland
| | - Daniel M Kerr
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland; Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, Ireland; Galway Neuroscience Centre and Centre for Pain Research, NCBES, National University of Ireland, Galway, Ireland
| | - David P Finn
- Pharmacology and Therapeutics, School of Medicine, National University of Ireland, Galway, Ireland; Galway Neuroscience Centre and Centre for Pain Research, NCBES, National University of Ireland, Galway, Ireland
| | - Michelle Roche
- Physiology, School of Medicine, National University of Ireland, Galway, Ireland; Galway Neuroscience Centre and Centre for Pain Research, NCBES, National University of Ireland, Galway, Ireland.
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29
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Qi M, Morena M, Vecchiarelli HA, Hill MN, Schriemer DC. A robust capillary liquid chromatography/tandem mass spectrometry method for quantitation of neuromodulatory endocannabinoids. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2015; 29:1889-1897. [PMID: 26411510 DOI: 10.1002/rcm.7277] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 07/02/2015] [Accepted: 07/12/2015] [Indexed: 06/05/2023]
Abstract
RATIONALE Methods for quantifying anandamide (AEA) and 2-arachidonoyl glycerol (2-AG) are needed to support programs investigating molecular mechanisms of the central nervous system. Existing methods, while useful, are not well adapted to efficiently process large numbers of very small tissue samples. A unique challenge involves the disparity in endogenous levels of AEA (pmol/g tissue) and 2-AG (nmol/g tissue). METHODS A simplified one-step solvent extraction procedure was developed for recovering endocannabinoids from rat brain tissues, and combined with capillary liquid chromatography/tandem mass spectrometry (LC/MS/MS). Various multiple reaction monitoring (MRM)-based methods were evaluated for limit of detection (LOD) and robustness. RESULTS The optimized simultaneous quantitation method achieves an LOQ of 50 amol for AEA and 25 fmol for 2-AG, both with a linearity over 3 orders of magnitude, and elution times under 3 min. Accuracy, expressed as relative error (RE), is less than 12% for AEA and less than 6% for 2-AG. Precision, expressed as relative standard deviation (RSD), is less than 6% for AEA and less than 3% for 2-AG. Sample handling routines are sufficiently robust to support the automated analysis of thousands of samples from a range of tissue types. CONCLUSIONS The microscale method is a sensitive, economical and robust alternative to the larger scale LC/MS methods currently implemented for quantitation of AEA and 2-AG.
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Affiliation(s)
- Ming Qi
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Alberta, Canada, T2N 4N1
| | - Maria Morena
- Department of Cell Biology & Anatomy and Psychiatry, University of Calgary, Calgary, Alberta, Canada, T2N 4N1
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada, T2N 4N1
| | - Haley A Vecchiarelli
- Department of Neuroscience, University of Calgary, Calgary, Alberta, Canada, T2N 4N1
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada, T2N 4N1
| | - Matthew N Hill
- Department of Cell Biology & Anatomy and Psychiatry, University of Calgary, Calgary, Alberta, Canada, T2N 4N1
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada, T2N 4N1
| | - David C Schriemer
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Alberta, Canada, T2N 4N1
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Fitzgibbon M, Finn DP, Roche M. High Times for Painful Blues: The Endocannabinoid System in Pain-Depression Comorbidity. Int J Neuropsychopharmacol 2015; 19:pyv095. [PMID: 26342110 PMCID: PMC4815466 DOI: 10.1093/ijnp/pyv095] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 08/17/2015] [Indexed: 01/06/2023] Open
Abstract
Depression and pain are two of the most debilitating disorders worldwide and have an estimated cooccurrence of up to 80%. Comorbidity of these disorders is more difficult to treat, associated with significant disability and impaired health-related quality of life than either condition alone, resulting in enormous social and economic cost. Several neural substrates have been identified as potential mediators in the association between depression and pain, including neuroanatomical reorganization, monoamine and neurotrophin depletion, dysregulation of the hypothalamo-pituitary-adrenal axis, and neuroinflammation. However, the past decade has seen mounting evidence supporting a role for the endogenous cannabinoid (endocannabinoid) system in affective and nociceptive processing, and thus, alterations in this system may play a key role in reciprocal interactions between depression and pain. This review will provide an overview of the preclinical evidence supporting an interaction between depression and pain and the evidence supporting a role for the endocannabinoid system in this interaction.
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Affiliation(s)
| | | | - Michelle Roche
- Physiology (Ms Fitzgibbon and Dr Roche), and Pharmacology and Therapeutics (Dr Finn), School of Medicine, Galway Neuroscience Centre and Centre for Pain Research (Ms Fitzgibbon, Dr Finn, and Dr Roche), National Centre for Biomedical Engineering Science, National University of Ireland Galway, Ireland.
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