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Hamel R, Oyler R, Harms E, Bailey R, Rendeiro C, Jenkinson N. Dietary Cocoa Flavanols Do Not Alter Brain Excitability in Young Healthy Adults. Nutrients 2024; 16:969. [PMID: 38613003 PMCID: PMC11013095 DOI: 10.3390/nu16070969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/21/2024] [Accepted: 03/26/2024] [Indexed: 04/14/2024] Open
Abstract
The ingestion of dietary cocoa flavanols acutely alters functions of the cerebral endothelium, but whether the effects of flavanols permeate beyond this to alter other brain functions remains unclear. Based on converging evidence, this work tested the hypothesis that cocoa flavanols would alter brain excitability in young healthy adults. In a randomised, cross-over, double-blinded, placebo-controlled design, transcranial magnetic stimulation was used to assess corticospinal and intracortical excitability before as well as 1 and 2 h post-ingestion of a beverage containing either high (695 mg flavanols, 150 mg (-)-epicatechin) or low levels (5 mg flavanols, 0 mg (-)-epicatechin) of cocoa flavanols. In addition to this acute intervention, the effects of a short-term chronic intervention where the same cocoa flavanol doses were ingested once a day for 5 consecutive days were also investigated. For both the acute and chronic interventions, the results revealed no robust alteration in corticospinal or intracortical excitability. One possibility is that cocoa flavanols yield no net effect on brain excitability, but predominantly alter functions of the cerebral endothelium in young healthy adults. Future studies should increase intervention durations to maximize the acute and chronic accumulation of flavanols in the brain, and further investigate if cocoa flavanols would be more effective at altering brain excitability in older adults and clinical populations than in younger adults.
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Affiliation(s)
- Raphael Hamel
- School of Sports, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham B15 2TT, UK
- Centre for Human Brain Health, School of Psychology, University of Birmingham, Birmingham B15 2TT, UK
| | - Rebecca Oyler
- School of Sports, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Evie Harms
- School of Sports, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Rosamond Bailey
- School of Sports, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Catarina Rendeiro
- School of Sports, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham B15 2TT, UK
- Centre for Human Brain Health, School of Psychology, University of Birmingham, Birmingham B15 2TT, UK
| | - Ned Jenkinson
- School of Sports, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham B15 2TT, UK
- Centre for Human Brain Health, School of Psychology, University of Birmingham, Birmingham B15 2TT, UK
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Fronza MG, Ferreira BF, Pavan-Silva I, Guimarães FS, Lisboa SF. "NO" Time in Fear Response: Possible Implication of Nitric-Oxide-Related Mechanisms in PTSD. Molecules 2023; 29:89. [PMID: 38202672 PMCID: PMC10779493 DOI: 10.3390/molecules29010089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/05/2023] [Accepted: 12/20/2023] [Indexed: 01/12/2024] Open
Abstract
Post-traumatic stress disorder (PTSD) is a psychiatric condition characterized by persistent fear responses and altered neurotransmitter functioning due to traumatic experiences. Stress predominantly affects glutamate, a neurotransmitter crucial for synaptic plasticity and memory formation. Activation of the N-Methyl-D-Aspartate glutamate receptors (NMDAR) can trigger the formation of a complex comprising postsynaptic density protein-95 (PSD95), the neuronal nitric oxide synthase (nNOS), and its adaptor protein (NOS1AP). This complex is pivotal in activating nNOS and nitric oxide (NO) production, which, in turn, activates downstream pathways that modulate neuronal signaling, including synaptic plasticity/transmission, inflammation, and cell death. The involvement of nNOS and NOS1AP in the susceptibility of PTSD and its comorbidities has been widely shown. Therefore, understanding the interplay between stress, fear, and NO is essential for comprehending the maintenance and progression of PTSD, since NO is involved in fear acquisition and extinction processes. Moreover, NO induces post-translational modifications (PTMs), including S-nitrosylation and nitration, which alter protein function and structure for intracellular signaling. Although evidence suggests that NO influences synaptic plasticity and memory processing, the specific role of PTMs in the pathophysiology of PTSD remains unclear. This review highlights pathways modulated by NO that could be relevant to stress and PTSD.
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Affiliation(s)
- Mariana G. Fronza
- Pharmacology Departament, Ribeirão Preto Medical School, University of São Paulo, São Paulo 14049-900, Brazil; (M.G.F.); (B.F.F.); (I.P.-S.)
| | - Bruna F. Ferreira
- Pharmacology Departament, Ribeirão Preto Medical School, University of São Paulo, São Paulo 14049-900, Brazil; (M.G.F.); (B.F.F.); (I.P.-S.)
| | - Isabela Pavan-Silva
- Pharmacology Departament, Ribeirão Preto Medical School, University of São Paulo, São Paulo 14049-900, Brazil; (M.G.F.); (B.F.F.); (I.P.-S.)
| | - Francisco S. Guimarães
- Pharmacology Departament, Ribeirão Preto Medical School, University of São Paulo, São Paulo 14049-900, Brazil; (M.G.F.); (B.F.F.); (I.P.-S.)
| | - Sabrina F. Lisboa
- Pharmacology Departament, Ribeirão Preto Medical School, University of São Paulo, São Paulo 14049-900, Brazil; (M.G.F.); (B.F.F.); (I.P.-S.)
- Biomolecular Sciences Department, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, São Paulo 14040-903, Brazil
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Yu G, Zhang Y, Ning B. Reactive Astrocytes in Central Nervous System Injury: Subgroup and Potential Therapy. Front Cell Neurosci 2022; 15:792764. [PMID: 35002629 PMCID: PMC8733560 DOI: 10.3389/fncel.2021.792764] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 12/07/2021] [Indexed: 12/13/2022] Open
Abstract
Traumatic central nervous system (CNS) injury, which includes both traumatic brain injury (TBI) and spinal cord injury (SCI), is associated with irreversible loss of neurological function and high medical care costs. Currently, no effective treatment exists to improve the prognosis of patients. Astrocytes comprise the largest population of glial cells in the CNS and, with the advancements in the field of neurology, are increasingly recognized as having key functions in both the brain and the spinal cord. When stimulated by disease or injury, astrocytes become activated and undergo a series of changes, including alterations in gene expression, hypertrophy, the loss of inherent functions, and the acquisition of new ones. Studies have shown that astrocytes are highly heterogeneous with respect to their gene expression profiles, and this heterogeneity accounts for their observed context-dependent phenotypic diversity. In the inured CNS, activated astrocytes play a dual role both as regulators of neuroinflammation and in scar formation. Identifying the subpopulations of reactive astrocytes that exert beneficial or harmful effects will aid in deciphering the pathological mechanisms underlying CNS injuries and ultimately provide a theoretical basis for the development of effective strategies for the treatment of associated conditions. Following CNS injury, as the disease progresses, astrocyte phenotypes undergo continuous changes. Although current research methods do not allow a comprehensive and accurate classification of astrocyte subpopulations in complex pathological contexts, they can nonetheless aid in understanding the roles of astrocytes in disease. In this review, after a brief introduction to the pathology of CNS injury, we summarize current knowledge regarding astrocyte activation following CNS injury, including: (a) the regulatory factors involved in this process; (b) the functions of different astrocyte subgroups based on the existing classification of astrocytes; and (c) attempts at astrocyte-targeted therapy.
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Affiliation(s)
- GuiLian Yu
- Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Ying Zhang
- Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Bin Ning
- Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
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Mouse models of immune dysfunction: their neuroanatomical differences reflect their anxiety-behavioural phenotype. Mol Psychiatry 2022; 27:3047-3055. [PMID: 35422470 PMCID: PMC9205773 DOI: 10.1038/s41380-022-01535-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 02/18/2022] [Accepted: 03/17/2022] [Indexed: 11/08/2022]
Abstract
Extensive evidence supports the role of the immune system in modulating brain function and behaviour. However, past studies have revealed striking heterogeneity in behavioural phenotypes produced from immune system dysfunction. Using magnetic resonance imaging, we studied the neuroanatomical differences among 11 distinct genetically modified mouse lines (n = 371), each deficient in a different element of the immune system. We found a significant and heterogeneous effect of immune dysfunction on the brains of both male and female mice. However, by imaging the whole brain and using Bayesian hierarchical modelling, we were able to identify patterns within the heterogeneous phenotype. Certain structures-such as the corpus callosum, midbrain, and thalamus-were more likely to be affected by immune dysfunction. A notable brain-behaviour relationship was identified with neuroanatomy endophenotypes across mouse models clustering according to anxiety-like behaviour phenotypes reported in literature, such as altered volume in brains regions associated with promoting fear response (e.g., the lateral septum and cerebellum). Interestingly, genes with preferential spatial expression in the most commonly affected regions are also associated with multiple sclerosis and other immune-mediated diseases. In total, our data suggest that the immune system modulates anxiety behaviour through well-established brain networks.
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Fernandes GG, Costa KCM, Scomparin DS, Freire JB, Guimarães FS, Campos AC. Genetic Ablation of the Inducible Form of Nitric Oxide in Male Mice Disrupts Immature Neuron Survival in the Adult Dentate Gyrus. Front Immunol 2021; 12:782831. [PMID: 34925362 PMCID: PMC8673740 DOI: 10.3389/fimmu.2021.782831] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/08/2021] [Indexed: 12/27/2022] Open
Abstract
Inducible nitric oxide synthase (iNOS) is an enzyme upregulated in the brain during neuroimmune stimuli which is associated with an oxidative and pro-inflammatory environment in several brain regions, including the hippocampal formation and the prefrontal cortex. The dentate gyrus of the hippocampal formation is the site of a process known as adult hippocampal neurogenesis (AHN). Although many endogenous and extrinsic factors can modulate AHN, the exact participation of specific proinflammatory mediators such as iNOS in these processes remains to be fully elucidated. Here, we investigated how the total genetic ablation of iNOS impacts the hippocampal neurogenic niche and microglial phenotype and if these changes are correlated to the behavioral alterations observed in iNOS knockout (K.O.) mice submitted or not to the chronic unpredictable stress model (CUS - 21 days protocol). Contrary to our initial hypothesis, at control conditions, iNOS K.O. mice displayed no abnormalities on microglial activation in the dentate gyrus. However, they did exhibit impaired newborn cells and immature neuron survival, which was not affected by CUS. The reduction of AHN in iNOS K.O. mice was accompanied by an increased positive coping response in the tail suspension test and facilitation of anxiety-like behaviors in the novelty suppressed feeding. Next, we investigated whether a pro-neurogenic stimulus would rescue the neurogenic capacity of iNOS K.O. mice by administering in control and CUS groups the antidepressant escitalopram (ESC). The chronic treatment with ESC could not rescue the neurogenic capacity or the behavioral changes observed in iNOS K.O. mice. Besides, in the ventromedial prefrontal (vmPFC) cortex there was no change in the expression or the chronic activation of PV neurons (evaluated by double labeling PV with FOSB) in the prelimbic (PrL) or infralimbic subregions. FOSB expression, however, increased in the PrL of iNOS K.O. mice. Our results suggest that iNOS seems essential for the survival of newborn cells and immature neurons in the hippocampus and seem to partially explain the anxiogenic-like behavior observed in iNOS K.O. mice. On the other hand, the iNOS ablation appears to result in increased activity of the PrL which could explain the antidepressant-like behaviors of iNOS K.O mice.
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Affiliation(s)
| | | | | | | | | | - Alline C. Campos
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
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6
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Karanikas E. Psychologically Traumatic Oxidative Stress; A Comprehensive Review of Redox Mechanisms and Related Inflammatory Implications. PSYCHOPHARMACOLOGY BULLETIN 2021; 51:65-86. [PMID: 34887600 PMCID: PMC8601764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The organism's energy requirements for homeostatic balance are covered by the redox mechanisms. Yet in case of psychologically traumatic stress, allostatic regulations activate both pro-oxidant and antioxidant molecules as well as respective components of the inflammatory system. Thus a new setpoint of dynamic interactions among redox elements is reached. Similarly, a multifaceted interplay between redox and inflammatory fields is activated with the mediation of major effector systems such as the immune system, Hypothalamic-Pituitary-Adrenal axis, kynurenine, and the glycaemic regulatory one. In case of sustained and/or intense traumatic stress the prophylactic antioxidant components are inadequate to provide the organism with neuroprotection finally culminating in Oxidative Stress and subsequently to cellular apoptosis. In parallel multiple inflammatory systems trigger and/or are triggered by the redox systems in tight fashion so that the causation sequence appears obscure. This exhaustive review aims at the comprehension of the interaction among components of the redox system as well as to the collection of disperse findings relative to the redox-inflammatory interplay in the context of traumatic stress so that new research strategies could be developed.
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Affiliation(s)
- Evangelos Karanikas
- Karanikas, Department of Psychiatry, General Military Hospital, Thessaloniki, Greece
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7
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Cihankaya H, Theiss C, Matschke V. Significance of intercellular communication for neurodegenerative diseases. Neural Regen Res 2021; 17:1015-1017. [PMID: 34558526 PMCID: PMC8552856 DOI: 10.4103/1673-5374.324840] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Affiliation(s)
- Hilal Cihankaya
- Ruhr University Bochum, Medical Faculty, Institute of Anatomy, Department of Cytology; International Graduate School of Neuroscience (IGSN), Ruhr-University Bochum, Bochum, Germany
| | - Carsten Theiss
- Ruhr University Bochum, Medical Faculty, Institute of Anatomy, Department of Cytology; International Graduate School of Neuroscience (IGSN), Ruhr-University Bochum, Bochum, Germany
| | - Veronika Matschke
- Ruhr University Bochum, Medical Faculty, Institute of Anatomy, Department of Cytology, Bochum, Germany
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8
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Gao L, Penglee R, Huang Y, Yi X, Wang X, Liu L, Gong X, Bao B. CRISPR/Cas9-induced nos2b mutant zebrafish display behavioral abnormalities. GENES BRAIN AND BEHAVIOR 2020; 20:e12716. [PMID: 33200539 DOI: 10.1111/gbb.12716] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 11/13/2020] [Accepted: 11/16/2020] [Indexed: 11/29/2022]
Abstract
The immunomodulatory function of nitric oxide synthase (NOS2) has been extensively studied. However, some behavioral abnormalities caused by its mutations have been found in a few rodent studies, of which the molecular mechanism remains elusive. In this research, we generated nos2b gene knockout zebrafish (nos2bsou2/sou2 ) using CRISPR/Cas9 approach and investigated their behavioral and molecular changes by doing a series of behavioral detections, morphological measurements, and molecular analyses. We found that, compared with nos2b+/+ zebrafish, nos2bsou2/sou2 zebrafish exhibited enhanced motor activity; additionally, nos2bsou2/sou2 zebrafish were characterized by smaller brain size, abnormal structure of optic tectum, reduced mRNA level of presynaptic synaptophysin and postsynaptic homer1, and altered response to sodium nitroprusside/methylphenidate hydrochloride treatment. These findings will likely contribute to future studies of behavioral regulation.
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Affiliation(s)
- Lei Gao
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Rachit Penglee
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Yajuan Huang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Xinxin Yi
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Xiaojie Wang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Liping Liu
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Xiaoling Gong
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Baolong Bao
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
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Tedoldi A, Argent L, Montgomery JM. The role of the tripartite synapse in the heart: how glial cells may contribute to the physiology and pathophysiology of the intracardiac nervous system. Am J Physiol Cell Physiol 2020; 320:C1-C14. [PMID: 33085497 DOI: 10.1152/ajpcell.00363.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
One of the major roles of the intracardiac nervous system (ICNS) is to act as the final site of signal integration for efferent information destined for the myocardium to enable local control of heart rate and rhythm. Multiple subtypes of neurons exist in the ICNS where they are organized into clusters termed ganglionated plexi (GP). The majority of cells in the ICNS are actually glial cells; however, despite this, ICNS glial cells have received little attention to date. In the central nervous system, where glial cell function has been widely studied, glia are no longer viewed simply as supportive cells but rather have been shown to play an active role in modulating neuronal excitability and synaptic plasticity. Pioneering studies have demonstrated that in addition to glia within the brain stem, glial cells within multiple autonomic ganglia in the peripheral nervous system, including the ICNS, can also act to modulate cardiovascular function. Clinically, patients with atrial fibrillation (AF) undergoing catheter ablation show high plasma levels of S100B, a protein produced by cardiac glial cells, correlated with decreased AF recurrence. Interestingly, S100B also alters GP neuron excitability and neurite outgrowth in the ICNS. These studies highlight the importance of understanding how glial cells can affect the heart by modulating GP neuron activity or synaptic inputs. Here, we review studies investigating glia both in the central and peripheral nervous systems to discuss the potential role of glia in controlling cardiac function in health and disease, paying particular attention to the glial cells of the ICNS.
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Affiliation(s)
- Angelo Tedoldi
- Department of Physiology, University of Auckland, Auckland, New Zealand.,Manaaki Mānawa Centre for Heart Research, University of Auckland, Auckland, New Zealand
| | - Liam Argent
- Department of Physiology, University of Auckland, Auckland, New Zealand.,Manaaki Mānawa Centre for Heart Research, University of Auckland, Auckland, New Zealand
| | - Johanna M Montgomery
- Department of Physiology, University of Auckland, Auckland, New Zealand.,Manaaki Mānawa Centre for Heart Research, University of Auckland, Auckland, New Zealand
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Dual Roles of Astrocyte-Derived Factors in Regulation of Blood-Brain Barrier Function after Brain Damage. Int J Mol Sci 2019; 20:ijms20030571. [PMID: 30699952 PMCID: PMC6387062 DOI: 10.3390/ijms20030571] [Citation(s) in RCA: 146] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 01/23/2019] [Accepted: 01/27/2019] [Indexed: 12/13/2022] Open
Abstract
The blood-brain barrier (BBB) is a major functional barrier in the central nervous system (CNS), and inhibits the extravasation of intravascular contents and transports various essential nutrients between the blood and the brain. After brain damage by traumatic brain injury, cerebral ischemia and several other CNS disorders, the functions of the BBB are disrupted, resulting in severe secondary damage including brain edema and inflammatory injury. Therefore, BBB protection and recovery are considered novel therapeutic strategies for reducing brain damage. Emerging evidence suggests key roles of astrocyte-derived factors in BBB disruption and recovery after brain damage. The astrocyte-derived vascular permeability factors include vascular endothelial growth factors, matrix metalloproteinases, nitric oxide, glutamate and endothelin-1, which enhance BBB permeability leading to BBB disruption. By contrast, the astrocyte-derived protective factors include angiopoietin-1, sonic hedgehog, glial-derived neurotrophic factor, retinoic acid and insulin-like growth factor-1 and apolipoprotein E which attenuate BBB permeability resulting in recovery of BBB function. In this review, the roles of these astrocyte-derived factors in BBB function are summarized, and their significance as therapeutic targets for BBB protection and recovery after brain damage are discussed.
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11
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Nitric oxide signalling and antidepressant action revisited. Cell Tissue Res 2019; 377:45-58. [PMID: 30649612 DOI: 10.1007/s00441-018-02987-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 12/21/2018] [Indexed: 12/20/2022]
Abstract
Studies about the pathogenesis of mood disorders have consistently shown that multiple factors, including genetic and environmental, play a crucial role on their development and neurobiology. Multiple pathological theories have been proposed, of which several ultimately affects or is a consequence of dysfunction in brain neuroplasticity and homeostatic mechanisms. However, current clinical available pharmacological intervention, which is predominantly monoamine-based, suffers from a partial and lacking response even after weeks of continuous treatment. These issues raise the need for better understanding of aetiologies and brain abnormalities in depression, as well as developing novel treatment strategies. Nitric oxide (NO) is a gaseous unconventional neurotransmitter, which regulates and governs several important physiological functions in the central nervous system, including processes, which can be associated with the development of mood disorders. This review will present general aspects of the NO system in depression, highlighting potential targets that may be utilized and further explored as novel therapeutic targets in the future pharmacotherapy of depression. In particular, the review will link the importance of neuroplasticity mechanisms governed by NO to a possible molecular basis for the antidepressant effects.
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12
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Differential behavioral and glial responses induced by dopaminergic mechanisms in the iNOS knockout mice. Behav Brain Res 2018; 350:44-53. [PMID: 29751018 DOI: 10.1016/j.bbr.2018.05.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 04/05/2018] [Accepted: 05/03/2018] [Indexed: 11/23/2022]
Abstract
The interaction between distinctive nitric oxide synthase (NOS) isoforms and the dopamine system provides new avenues to the development of pharmacological tools for the pathophysiological conditions of the dopaminergic system. Our aim was to investigate the influences of dopamine-induced effects in inducible NOS knockout (iNOS KO) mice. In order to characterize iNOS KO mice phenotype, the animals were submitted to the basal analyses of motor, sensorimotor and sensorial abilities. Pharmacological challenging of the dopaminergic system included the investigation of amphetamine-induced prepulse inhibition (PPI) disruption, haloperidol-induced catalepsy, reserpine-induced oral involuntary movements and hyperlocomotion induced by amphetamine in reserpine treated mice. The iNOS KO mice showed significant reduction of spontaneous motor activity, but there was no significant difference in sensorimotor or sensorial responses of iNOS KO mice compared to wild type (WT). Regarding the dopaminergic system, iNOS KO mice showed a significant increase of haloperidol-induced catalepsy. This effect was confirmed through an iNOS pharmacological inhibitor (1400 W) in WT mice. In addition, iNOS KO reserpine treated mice showed reduced oral involuntary movements and amphetamine-induced hyperlocomotion. Knowing that iNOS is mainly expressed in glial cells we analyzed the immunoreactivity (ir) for GFAP (astrocyte marker) and IBA-1 (microglial marker) in the striatum, an area enrolled in motor planning among other functions. iNOS KO presented reduced GFAP-ir and IBA-1-ir compared with WT. Reserpine treatment increased GFAP-ir in both WT and iNOS KO. However, these effects were slighter in iNOS KO. Activated state of microglia was increased by reserpine only in WT mice. Our results further demonstrated that the absence of iNOS interfered with dopamine-mediated behavioral and molecular responses. These results increase the understanding of the dopamine and NO system interaction, which is useful for the management of the dopamine-related pathologies.
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Astrocytic modulation of neuronal excitability through K + spatial buffering. Neurosci Biobehav Rev 2017; 77:87-97. [PMID: 28279812 DOI: 10.1016/j.neubiorev.2017.03.002] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 03/05/2017] [Accepted: 03/05/2017] [Indexed: 11/22/2022]
Abstract
The human brain contains two major cell populations, neurons and glia. While neurons are electrically excitable and capable of discharging short voltage pulses known as action potentials, glial cells are not. However, astrocytes, the prevailing subtype of glia in the cortex, are highly connected and can modulate the excitability of neurons by changing the concentration of potassium ions in the extracellular environment, a process called K+ clearance. During the past decade, astrocytes have been the focus of much research, mainly due to their close association with synapses and their modulatory impact on neuronal activity. It has been shown that astrocytes play an essential role in normal brain function including: nitrosative regulation of synaptic release in the neocortex, synaptogenesis, synaptic transmission and plasticity. Here, we discuss the role of astrocytes in network modulation through their K+ clearance capabilities, a theory that was first raised 50 years ago by Orkand and Kuffler. We will discuss the functional alterations in astrocytic activity that leads to aberrant modulation of network oscillations and synchronous activity.
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14
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Cameron MA, Kekesi O, Morley JW, Bellot-Saez A, Kueh S, Breen P, van Schaik A, Tapson J, Buskila Y. Prolonged Incubation of Acute Neuronal Tissue for Electrophysiology and Calcium-imaging. J Vis Exp 2017. [PMID: 28287542 DOI: 10.3791/55396] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Acute neuronal tissue preparations, brain slices and retinal wholemount, can usually only be maintained for 6 - 8 h following dissection. This limits the experimental time, and increases the number of animals that are utilized per study. This limitation specifically impacts protocols such as calcium imaging that require prolonged pre-incubation with bath-applied dyes. Exponential bacterial growth within 3 - 4 h after slicing is tightly correlated with a decrease in tissue health. This study describes a method for limiting the proliferation of bacteria in acute preparations to maintain viable neuronal tissue for prolonged periods of time (>24 h) without the need for antibiotics, sterile procedures, or tissue culture media containing growth factors. By cycling the extracellular fluid through UV irradiation and keeping the tissue in a custom holding chamber at 15 - 16 °C, the tissue shows no difference in electrophysiological properties, or calcium signaling through intracellular calcium dyes at >24 h postdissection. These methods will not only extend experimental time for those using acute neuronal tissue, but will reduce the number of animals required to complete experimental goals, and will set a gold standard for acute neuronal tissue incubation.
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Affiliation(s)
| | - Orsolya Kekesi
- The MARCS Institute, Western Sydney University; School of Medicine, Western Sydney University
| | - John W Morley
- The MARCS Institute, Western Sydney University; School of Medicine, Western Sydney University
| | - Alba Bellot-Saez
- The MARCS Institute, Western Sydney University; School of Medicine, Western Sydney University
| | - Sindy Kueh
- School of Medicine, Western Sydney University
| | - Paul Breen
- The MARCS Institute, Western Sydney University
| | | | | | - Yossi Buskila
- The MARCS Institute, Western Sydney University; School of Medicine, Western Sydney University;
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15
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16
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Zhang C, Meng Q, Zhang X, Wu S, Wang S, Chen R, Li X. Role of astrocyte activation in fine particulate matter-enhancement of existing ischemic stroke in Sprague-Dawley male rats. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2016; 79:393-401. [PMID: 27267821 DOI: 10.1080/15287394.2016.1176615] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Exposure to particulate matter (PM) with an aerodynamic diameter of less than 2.5 μm (PM2.5) is associated with increased risk of ischemic stroke, but potential neurotoxic mechanisms remain to be determined. In this study, adult male Sprague- Dawley (SD) rats were divided into four groups as follows: control (CON), PM2.5 exposure (PM alone), ischemic stroke (IS), and ischemic stroke and PM2.5 (IS-PM). Ischemic stroke groups were prepared by middle cerebral artery occlusion (MCAO), and neurobehavior was assessed daily for 7 consecutive days. The control group was administered intranasally 20 μl PBS, while PM2.5 alone was given as 20 μl of PM2.5 (10 mg/ml) intranasal daily for 7 consecutive days. The spontaneous locomotion and exploratory behavior of rats were assessed by the open field test. Cells positive for glial fibrillary acidic protein (GFAP) and inducible nitric oxide synthase (iNOS) were determined for astrocyte activation and inflammatory reactions. Neuronal edema and pyknosis in the cerebral cortex, hippocampus, and midbrain were observed in IS groups with or without PM2.5 treatment. Astrocyte activity was enhanced, whereas spontaneous locomotion and exploratory movements decreased in the IS-PM group. Data demonstrated that astrocytes activation and inflammatory reactions may play a role in IS and that exposure to PM2.5 may aggravate the neurobehavioral alterations observed in rats suffering from IS.
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Affiliation(s)
- Chengcheng Zhang
- a Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health , Southeast University , Nanjing 210009 , China
| | - Qingtao Meng
- a Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health , Southeast University , Nanjing 210009 , China
| | - Xin Zhang
- a Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health , Southeast University , Nanjing 210009 , China
| | - Shenshen Wu
- a Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health , Southeast University , Nanjing 210009 , China
| | - Shizhi Wang
- a Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health , Southeast University , Nanjing 210009 , China
| | - Rui Chen
- a Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health , Southeast University , Nanjing 210009 , China
| | - Xiaobo Li
- a Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health , Southeast University , Nanjing 210009 , China
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17
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Uliana DL, Hott SC, Lisboa SF, Resstel LBM. Dorsolateral periaqueductal gray matter CB1 and TRPV1 receptors exert opposite modulation on expression of contextual fear conditioning. Neuropharmacology 2015; 103:257-69. [PMID: 26724373 DOI: 10.1016/j.neuropharm.2015.12.020] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 12/17/2015] [Accepted: 12/18/2015] [Indexed: 12/31/2022]
Abstract
Cannabinoid type 1 (CB1) and Transient Potential Vanilloid type 1 (TRPV1) receptors in the dorsolateral periaqueductal gray (dlPAG) matter are involved in the modulation of conditioned response. Both CB1 and TRPV1 receptors are related to glutamate release and nitric oxide (NO) synthesis. It was previously demonstrated that both NMDA glutamate receptors and NO are involved in the conditioned emotional response. Therefore, one aim of this work was to verify whether dlPAG CB1 and TRPV1 receptors modulate the expression of contextual conditioned emotional response. Moreover, we also investigated the involvement of NMDA receptors and the NO pathway in this response. Male Wistar rats with local dlPAG guide cannula were submitted to contextual fear conditioning. Following 24 h, a polyethylene catheter was implanted in the femoral artery for cardiovascular recordings. After an additional 24 h, drugs were administered in the dlPAG and freezing behavior and autonomic responses were recorded during chamber re-exposure. Both a CB1 antagonist (AM251) and a TRPV1 agonist (Capsaicin; CPS) increased the expression of a conditioned emotional response. This response was prevented by an NMDA antagonist, a preferential neuronal NO synthase inhibitor, an NO scavenger and a soluble guanylate cyclase inhibitor (sGC). Furthermore, pretreatment with a TRPV1 antagonist also prevented the increased conditioned emotional response induced by AM251. Considering that GABA can counterbalance glutamate effects, we also investigated whether GABAA receptors were involved in the effect of a higher dose of AM251. Pretreatment with a GABAA receptor antagonist caused an increased conditioned emotional response by AM251. Our results support the possibility that dlPAG CB1 and TRPV1 receptors are involved in the expression of conditioned emotional response through the NMDA/NO/sGC pathway. Moreover, the opposite effects exerted by GABA and glutamate could produce different outcomes of drugs modulating eCBs.
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Affiliation(s)
- D L Uliana
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Brazil
| | - S C Hott
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Brazil
| | - S F Lisboa
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Brazil.
| | - L B M Resstel
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Brazil.
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Bergstrom HC, Darvesh AS, Berger SP. Inducible Nitric Oxide Inhibitors Block NMDA Antagonist-Stimulated Motoric Behaviors and Medial Prefrontal Cortical Glutamate Efflux. Front Pharmacol 2015; 6:292. [PMID: 26696891 PMCID: PMC4678197 DOI: 10.3389/fphar.2015.00292] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 11/23/2015] [Indexed: 11/20/2022] Open
Abstract
Nitric oxide (NO) plays a critical role in the motoric and glutamate releasing action of N-methyl-D-aspartate (NMDA)-antagonist stimulants. Earlier studies utilized neuronal nitric oxide synthase inhibitors (nNOS) for studying the neurobehavioral effects of non-competitive NMDA-antagonist stimulants such as dizocilpine (MK-801) and phencyclidine (PCP). This study explores the role of the inducible nitric oxide synthase inhibitors (iNOS) aminoguanidine (AG) and (-)-epigallocatechin-3-gallate (EGCG) in NMDA-antagonist induced motoric behavior and prefrontal cortical glutamate efflux. Adult male rats were administered a dose range of AG, EGCG, or vehicle prior to receiving NMDA antagonists MK-801, PCP, or a conventional psychostimulant (cocaine) and tested for motoric behavior in an open arena. Glutamate in the medial prefrontal cortex (mPFC) was measured using in vivo microdialysis after a combination of AG or EGCG prior to MK-801. Acute administration of AG or EGCG dose-dependently attenuated the locomotor and ataxic properties of MK-801 and PCP. Both AG and EGCG were unable to block the motoric effects of cocaine, indicating the acute pharmacologic action of AG and EGCG is specific to NMDA antagonism and not generalizable to all stimulant class drugs. AG and EGCG normalized MK-801-stimulated mPFC glutamate efflux. These data demonstrate that AG and EGCG attenuates NMDA antagonist-stimulated motoric behavior and cortical glutamate efflux. Our results suggest that EGCG-like polyphenol nutraceuticals (contained in “green tea” and chocolate) may be clinically useful in protecting against the adverse behavioral dissociative and cortical glutamate stimulating effects of NMDA antagonists. Medications that interfere with NMDA antagonists such as MK-801 and PCP have been proposed as treatments for schizophrenia.
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Affiliation(s)
- Hadley C Bergstrom
- Department of Psychology, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie NY, USA
| | - Altaf S Darvesh
- Department of Pharmaceutical Sciences, College of Pharmacy, Northeast Ohio Medical University, Rootstown OH, USA ; Department of Psychiatry, College of Medicine, Northeast Ohio Medical University, Rootstown OH, USA
| | - S P Berger
- Department of Veterans Affairs Medical Center, Portland OR, USA
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Breen PP, Buskila Y. Braincubator: an incubation system to extend brain slice lifespan for use in neurophysiology. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2014:4864-7. [PMID: 25571081 DOI: 10.1109/embc.2014.6944713] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In vitro brain slice preparations are instrumental in developing our understanding of the nervous system. However, the current lifespan of an acute brain slice is limited to approximately 6-12 hours. This reduces potential experimentation time and leads to considerable waste of neural tissue. We have designed, developed and tested a novel incubation system capable of extending the lifespan of these brain slices. This is done by controlling the temperature and pH of the artificial cerebral spinal fluid in which the slices are incubated while continuously passing the fluid through a UVC filtration system. This system is capable of maintaining extremely low bacterial levels and significantly extending the brain slice lifespan to at least 24 hours. Brain slice viability was validated through electrophysiological recordings as well as live/dead cell assays.
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20
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Xie AX, Petravicz J, McCarthy KD. Molecular approaches for manipulating astrocytic signaling in vivo. Front Cell Neurosci 2015; 9:144. [PMID: 25941472 PMCID: PMC4403552 DOI: 10.3389/fncel.2015.00144] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 03/27/2015] [Indexed: 12/26/2022] Open
Abstract
Astrocytes are the predominant glial type in the central nervous system and play important roles in assisting neuronal function and network activity. Astrocytes exhibit complex signaling systems that are essential for their normal function and the homeostasis of the neural network. Altered signaling in astrocytes is closely associated with neurological and psychiatric diseases, suggesting tremendous therapeutic potential of these cells. To further understand astrocyte function in health and disease, it is important to study astrocytic signaling in vivo. In this review, we discuss molecular tools that enable the selective manipulation of astrocytic signaling, including the tools to selectively activate and inactivate astrocyte signaling in vivo. Lastly, we highlight a few tools in development that present strong potential for advancing our understanding of the role of astrocytes in physiology, behavior, and pathology.
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Affiliation(s)
- Alison X Xie
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill Chapel Hill, NC, USA
| | - Jeremy Petravicz
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology Cambridge, MA, USA
| | - Ken D McCarthy
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill Chapel Hill, NC, USA
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21
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Muñoz MF, Puebla M, Figueroa XF. Control of the neurovascular coupling by nitric oxide-dependent regulation of astrocytic Ca(2+) signaling. Front Cell Neurosci 2015; 9:59. [PMID: 25805969 PMCID: PMC4354411 DOI: 10.3389/fncel.2015.00059] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 02/07/2015] [Indexed: 12/28/2022] Open
Abstract
Neuronal activity must be tightly coordinated with blood flow to keep proper brain function, which is achieved by a mechanism known as neurovascular coupling. Then, an increase in synaptic activity leads to a dilation of local parenchymal arterioles that matches the enhanced metabolic demand. Neurovascular coupling is orchestrated by astrocytes. These glial cells are located between neurons and the microvasculature, with the astrocytic endfeet ensheathing the vessels, which allows fine intercellular communication. The neurotransmitters released during neuronal activity reach astrocytic receptors and trigger a Ca2+ signaling that propagates to the endfeet, activating the release of vasoactive factors and arteriolar dilation. The astrocyte Ca2+ signaling is coordinated by gap junction channels and hemichannels formed by connexins (Cx43 and Cx30) and channels formed by pannexins (Panx-1). The neuronal activity-initiated Ca2+ waves are propagated among neighboring astrocytes directly via gap junctions or through ATP release via connexin hemichannels or pannexin channels. In addition, Ca2+ entry via connexin hemichannels or pannexin channels may participate in the regulation of the astrocyte signaling-mediated neurovascular coupling. Interestingly, nitric oxide (NO) can activate connexin hemichannel by S-nitrosylation and the Ca2+-dependent NO-synthesizing enzymes endothelial NO synthase (eNOS) and neuronal NOS (nNOS) are expressed in astrocytes. Therefore, the astrocytic Ca2+ signaling triggered in neurovascular coupling may activate NO production, which, in turn, may lead to Ca2+ influx through hemichannel activation. Furthermore, NO release from the hemichannels located at astrocytic endfeet may contribute to the vasodilation of parenchymal arterioles. In this review, we discuss the mechanisms involved in the regulation of the astrocytic Ca2+ signaling that mediates neurovascular coupling, with a special emphasis in the possible participation of NO in this process.
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Affiliation(s)
- Manuel F Muñoz
- Facultad de Ciencias Biológicas, Departamento de Fisiología, Pontificia Universidad Católica de Chile Santiago, Chile
| | - Mariela Puebla
- Facultad de Ciencias Biológicas, Departamento de Fisiología, Pontificia Universidad Católica de Chile Santiago, Chile
| | - Xavier F Figueroa
- Facultad de Ciencias Biológicas, Departamento de Fisiología, Pontificia Universidad Católica de Chile Santiago, Chile
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22
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Lisboa SF, Gomes FV, Silva AL, Uliana DL, Camargo LHA, Guimarães FS, Cunha FQ, Joca SRL, Resstel LBM. Increased Contextual Fear Conditioning in iNOS Knockout Mice: Additional Evidence for the Involvement of Nitric Oxide in Stress-Related Disorders and Contribution of the Endocannabinoid System. Int J Neuropsychopharmacol 2015; 18:pyv005. [PMID: 25618404 PMCID: PMC4571624 DOI: 10.1093/ijnp/pyv005] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 01/12/2015] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Inducible or neuronal nitric oxide synthase gene deletion increases or decreases anxiety-like behavior in mice, respectively. Since nitric oxide and endocannabinoids interact to modulate defensive behavior, the former effect could involve a compensatory increase in basal brain nitric oxide synthase activity and/or changes in the endocannabinoid system. Thus, we investigated the expression and extinction of contextual fear conditioning of inducible nitric oxide knockout mice and possible involvement of endocannabinoids in these responses. METHODS We evaluated the effects of a preferential neuronal nitric oxide synthase inhibitor, 7-nitroindazol, nitric oxide synthase activity, and mRNA changes of nitrergic and endocannabinoid systems components in the medial prefrontal cortex and hippocampus of wild-type and knockout mice. The effects of URB597, an inhibitor of the fatty acid amide hydrolase enzyme, which metabolizes the endocannabinoid anandamide, WIN55,212-2, a nonselective cannabinoid agonist, and AM281, a selective CB1 antagonist, on contextual fear conditioning were also evaluated. RESULTS Contextual fear conditioning expression was similar in wild-type and knockout mice, but the latter presented extinction deficits and increased basal nitric oxide synthase activity in the medial prefrontal cortex. 7-Nitroindazol decreased fear expression and facilitated extinction in wild-type and knockout mice. URB597 decreased fear expression in wild-type and facilitated extinction in knockout mice, whereas WIN55,212-2 and AM281 increased it in wild-type mice. Nonconditioned knockout mice showed changes in the mRNA expression of nitrergic and endocannabinoid system components in the medial prefrontal cortex and hippocampus that were modified by fear conditioning. CONCLUSION These data reinforce the involvement of the nitric oxide and endocannabinoids (anandamide) in stress-related disorders and point to a deregulation of the endocannabinoid system in situations where nitric oxide signaling is increased.
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MESH Headings
- Animals
- Arachidonic Acids/metabolism
- Benzamides/pharmacology
- Benzoxazines/pharmacology
- Cannabinoid Receptor Agonists/pharmacology
- Cannabinoid Receptor Antagonists/pharmacology
- Carbamates/pharmacology
- Conditioning, Psychological/drug effects
- Conditioning, Psychological/physiology
- Endocannabinoids/metabolism
- Enzyme Inhibitors/pharmacology
- Extinction, Psychological/drug effects
- Extinction, Psychological/physiology
- Fear/drug effects
- Fear/physiology
- Freezing Reaction, Cataleptic/drug effects
- Freezing Reaction, Cataleptic/physiology
- Hippocampus/drug effects
- Hippocampus/metabolism
- Indazoles/pharmacology
- Male
- Mice, Inbred C57BL
- Mice, Knockout
- Morpholines/pharmacology
- Naphthalenes/pharmacology
- Nitric Oxide/metabolism
- Nitric Oxide Synthase Type II/antagonists & inhibitors
- Nitric Oxide Synthase Type II/genetics
- Nitric Oxide Synthase Type II/metabolism
- Polyunsaturated Alkamides/metabolism
- Prefrontal Cortex/drug effects
- Prefrontal Cortex/metabolism
- Pyrazoles/pharmacology
- RNA, Messenger/metabolism
- Receptor, Cannabinoid, CB1/antagonists & inhibitors
- Receptor, Cannabinoid, CB1/metabolism
- Stress, Psychological/metabolism
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Affiliation(s)
- Sabrina F Lisboa
- Department of Pharmacology, Medical School of Ribeirão Preto (Drs Lisboa, Gomes, Silva, Cunha, and Resstel, Ms Uliana and Ms Camargo), Department of Pharmacology, School of Pharmaceutical Sciences of Ribeirão Preto (Dr Joca), and Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Drs Lisboa, Gomes, Guimarães, Joca, and Resstel).
| | - Felipe V Gomes
- Department of Pharmacology, Medical School of Ribeirão Preto (Drs Lisboa, Gomes, Silva, Cunha, and Resstel, Ms Uliana and Ms Camargo), Department of Pharmacology, School of Pharmaceutical Sciences of Ribeirão Preto (Dr Joca), and Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Drs Lisboa, Gomes, Guimarães, Joca, and Resstel)
| | - Andréia L Silva
- Department of Pharmacology, Medical School of Ribeirão Preto (Drs Lisboa, Gomes, Silva, Cunha, and Resstel, Ms Uliana and Ms Camargo), Department of Pharmacology, School of Pharmaceutical Sciences of Ribeirão Preto (Dr Joca), and Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Drs Lisboa, Gomes, Guimarães, Joca, and Resstel)
| | - Daniela L Uliana
- Department of Pharmacology, Medical School of Ribeirão Preto (Drs Lisboa, Gomes, Silva, Cunha, and Resstel, Ms Uliana and Ms Camargo), Department of Pharmacology, School of Pharmaceutical Sciences of Ribeirão Preto (Dr Joca), and Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Drs Lisboa, Gomes, Guimarães, Joca, and Resstel)
| | - Laura H A Camargo
- Department of Pharmacology, Medical School of Ribeirão Preto (Drs Lisboa, Gomes, Silva, Cunha, and Resstel, Ms Uliana and Ms Camargo), Department of Pharmacology, School of Pharmaceutical Sciences of Ribeirão Preto (Dr Joca), and Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Drs Lisboa, Gomes, Guimarães, Joca, and Resstel)
| | - Francisco S Guimarães
- Department of Pharmacology, Medical School of Ribeirão Preto (Drs Lisboa, Gomes, Silva, Cunha, and Resstel, Ms Uliana and Ms Camargo), Department of Pharmacology, School of Pharmaceutical Sciences of Ribeirão Preto (Dr Joca), and Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Drs Lisboa, Gomes, Guimarães, Joca, and Resstel)
| | - Fernando Q Cunha
- Department of Pharmacology, Medical School of Ribeirão Preto (Drs Lisboa, Gomes, Silva, Cunha, and Resstel, Ms Uliana and Ms Camargo), Department of Pharmacology, School of Pharmaceutical Sciences of Ribeirão Preto (Dr Joca), and Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Drs Lisboa, Gomes, Guimarães, Joca, and Resstel)
| | - Sâmia R L Joca
- Department of Pharmacology, Medical School of Ribeirão Preto (Drs Lisboa, Gomes, Silva, Cunha, and Resstel, Ms Uliana and Ms Camargo), Department of Pharmacology, School of Pharmaceutical Sciences of Ribeirão Preto (Dr Joca), and Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Drs Lisboa, Gomes, Guimarães, Joca, and Resstel)
| | - Leonardo B M Resstel
- Department of Pharmacology, Medical School of Ribeirão Preto (Drs Lisboa, Gomes, Silva, Cunha, and Resstel, Ms Uliana and Ms Camargo), Department of Pharmacology, School of Pharmaceutical Sciences of Ribeirão Preto (Dr Joca), and Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Drs Lisboa, Gomes, Guimarães, Joca, and Resstel)
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Modifying welding process parameters can reduce the neurotoxic potential of manganese-containing welding fumes. Toxicology 2014; 328:168-78. [PMID: 25549921 DOI: 10.1016/j.tox.2014.12.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 12/14/2014] [Indexed: 11/21/2022]
Abstract
Welding fumes (WF) are a complex mixture of toxic metals and gases, inhalation of which can lead to adverse health effects among welders. The presence of manganese (Mn) in welding electrodes is cause for concern about the potential development of Parkinson's disease (PD)-like neurological disorder. Consequently, from an occupational safety perspective, there is a critical need to prevent adverse exposures to WF. As the fume generation rate and physicochemical characteristics of welding aerosols are influenced by welding process parameters like voltage, current or shielding gas, we sought to determine if changing such parameters can alter the fume profile and consequently its neurotoxic potential. Specifically, we evaluated the influence of voltage on fume composition and neurotoxic outcome. Rats were exposed by whole-body inhalation (40 mg/m(3); 3h/day × 5 d/week × 2 weeks) to fumes generated by gas-metal arc welding using stainless steel electrodes (GMA-SS) at standard/regular voltage (25 V; RVSS) or high voltage (30 V; HVSS). Fumes generated under these conditions exhibited similar particulate morphology, appearing as chain-like aggregates; however, HVSS fumes comprised of a larger fraction of ultrafine particulates that are generally considered to be more toxic than their fine counterparts. Paradoxically, exposure to HVSS fumes did not elicit dopaminergic neurotoxicity, as monitored by the expression of dopaminergic and PD-related markers. We show that the lack of neurotoxicity is due to reduced solubility of Mn in HVSS fumes. Our findings show promise for process control procedures in developing prevention strategies for Mn-related neurotoxicity during welding; however, it warrants additional investigations to determine if such modifications can be suitably adapted at the workplace to avert or reduce adverse neurological risks.
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24
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Li XB, Zhang X, Ju J, Li Y, Yin L, Pu Y. Alterations in neurobehaviors and inflammation in hippocampus of rats induced by oral administration of microcystin-LR. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:12419-12425. [PMID: 24938810 DOI: 10.1007/s11356-014-3151-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 06/03/2014] [Indexed: 06/03/2023]
Abstract
Microcystin-LR (MC-LR) is a widely studied toxic peptide secreted by certain water blooms of cyanobacteria that exhibit hepatotoxicity and neural toxicity. This study aimed to observe the neurotoxic effects of low-dose MC-LR exposure by oral administration. Male Sprague-Dawley (SD) rats were administered orally every 2 days for 8 weeks with pure water and 0.2, 1.0, and 5.0 μg/kg MC-LR. The Morris water maze test was used to assess the spatial learning and memory capability of rats. The activation of astrocytes and nitric oxide synthase (NOS) was evaluated by immunohistochemistry, and concentrations of nitric oxide (NO) in rat hippocampus were analyzed. Slight liver dysfunction was observed in the 5.0 μg/kg MC-LR-treated rats. Impairment of spatial learning and memory was also observed in the 5.0 μg/kg MC-LR-treated rats. Astrocytes in the hippocampus of the 5.0 μg/kg MC-LR-treated rats showed enhanced activation and cell density; the inflammatory indicators, NOS and NO, increased in accordance with astrocyte activation. This study showed that oral exposure of MC-LR had adverse affects on neurobehaviors, and induced inflammation in memory-related brain regions.
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Affiliation(s)
- Xiao-Bo Li
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Dingjiaqiao 87, Nanjing, 210009, China,
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25
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Li T, Shi T, Li X, Zeng S, Yin L, Pu Y. Effects of Nano-MnO2 on dopaminergic neurons and the spatial learning capability of rats. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2014; 11:7918-30. [PMID: 25101772 PMCID: PMC4143840 DOI: 10.3390/ijerph110807918] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 07/16/2014] [Accepted: 07/25/2014] [Indexed: 01/22/2023]
Abstract
This study aimed to observe the effect of intracerebrally injected nano-MnO2 on neurobehavior and the functions of dopaminergic neurons and astrocytes. Nano-MnO2, 6-OHDA, and saline (control) were injected in the substantia nigra and the ventral tegmental area of Sprague-Dawley rat brains. The neurobehavior of rats was evaluated by Morris water maze test. Tyrosine hydroxylase (TH), inducible nitric oxide synthase (iNOS) and glial fibrillary acidic protein (GFAP) expressions in rat brain were detected by immunohistochemistry. Results showed that the escape latencies of nano-MnO2 treated rat increased significantly compared with control. The number of TH-positive cells decreased, GFAP- and iNOS-positive cells increased significantly in the lesion side of the rat brains compared with the contralateral area in nano-MnO2 group. The same tendencies were observed in nano-MnO2-injected rat brains compared with control. However, in the the positive control, 6-OHDA group, escape latencies increased, TH-positive cell number decreased significantly compared with nano-MnO2 group. The alteration of spatial learning abilities of rats induced by nano-MnO2 may be associated with dopaminergic neuronal dysfunction and astrocyte activation.
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Affiliation(s)
- Tao Li
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China.
| | - Tingting Shi
- Institute of Neurobiology, Southeast University, Nanjing 210009, China.
| | - Xiaobo Li
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China.
| | - Shuilin Zeng
- Institute of Neurobiology, Southeast University, Nanjing 210009, China.
| | - Lihong Yin
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China.
| | - Yuepu Pu
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China.
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26
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Abstract
The lifespan of an acute brain slice is approximately 6–12 hours, limiting potential experimentation time. We have designed a new recovery incubation system capable of extending their lifespan to more than 36 hours. This system controls the temperature of the incubated artificial cerebral spinal fluid (aCSF) while continuously passing the fluid through a UVC filtration system and simultaneously monitoring temperature and pH. The combination of controlled temperature and UVC filtering maintains bacteria levels in the lag phase and leads to the dramatic extension of the brain slice lifespan. Brain slice viability was validated through electrophysiological recordings as well as live/dead cell assays. This system benefits researchers by monitoring incubation conditions and standardizing this artificial environment. It further provides viable tissue for two experimental days, reducing the time spent preparing brain slices and the number of animals required for research.
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27
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Béchade C, Colasse S, Diana MA, Rouault M, Bessis A. NOS2 expression is restricted to neurons in the healthy brain but is triggered in microglia upon inflammation. Glia 2014; 62:956-63. [DOI: 10.1002/glia.22652] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 02/04/2014] [Accepted: 02/07/2014] [Indexed: 01/13/2023]
Affiliation(s)
- Catherine Béchade
- Institut de Biologie de l'Ecole Normale Supérieure; F-75005 Paris France
- Institut National de la Santé et de la Recherche Médicale U1024; F-75005 Paris France
- Centre National de la Recherche Scientifique; Unité Mixte de Recherche 8197 F-75005 France
| | - Sabrina Colasse
- Institut de Biologie de l'Ecole Normale Supérieure; F-75005 Paris France
- Institut National de la Santé et de la Recherche Médicale U1024; F-75005 Paris France
- Centre National de la Recherche Scientifique; Unité Mixte de Recherche 8197 F-75005 France
| | - Marco A. Diana
- Institut de Biologie de l'Ecole Normale Supérieure; F-75005 Paris France
- Institut National de la Santé et de la Recherche Médicale U1024; F-75005 Paris France
- Centre National de la Recherche Scientifique; Unité Mixte de Recherche 8197 F-75005 France
| | - Martin Rouault
- Institut de Biologie de l'Ecole Normale Supérieure; F-75005 Paris France
- Institut National de la Santé et de la Recherche Médicale U1024; F-75005 Paris France
- Centre National de la Recherche Scientifique; Unité Mixte de Recherche 8197 F-75005 France
| | - Alain Bessis
- Institut de Biologie de l'Ecole Normale Supérieure; F-75005 Paris France
- Institut National de la Santé et de la Recherche Médicale U1024; F-75005 Paris France
- Centre National de la Recherche Scientifique; Unité Mixte de Recherche 8197 F-75005 France
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Contestabile A, Monti B, Polazzi E. Neuronal-glial Interactions Define the Role of Nitric Oxide in Neural Functional Processes. Curr Neuropharmacol 2012; 10:303-10. [PMID: 23730254 PMCID: PMC3520040 DOI: 10.2174/157015912804143522] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 06/07/2012] [Accepted: 06/24/2012] [Indexed: 01/01/2023] Open
Abstract
Nitric oxide (NO) is a versatile cellular messenger performing a variety of physiologic and pathologic actions in most tissues. It is particularly important in the nervous system, where it is involved in multiple functions, as well as in neuropathology, when produced in excess. Several of these functions are based on interactions between NO produced by neurons and NO produced by glial cells, mainly astrocytes and microglia. The present paper briefly reviews some of these interactions, in particular those involved in metabolic regulation, control of cerebral blood flow, axonogenesis, synaptic function and neurogenesis. Aim of the paper is mainly to underline the physiologic aspects of these interactions rather than the pathologic ones.
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Streifel KM, Moreno JA, Hanneman WH, Legare ME, Tjalkens RB. Gene deletion of nos2 protects against manganese-induced neurological dysfunction in juvenile mice. Toxicol Sci 2012; 126:183-92. [PMID: 22174044 PMCID: PMC3289496 DOI: 10.1093/toxsci/kfr335] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 12/02/2011] [Indexed: 01/15/2023] Open
Abstract
The mechanisms underlying cognitive and neurobehavioral abnormalities associated with childhood exposure to manganese (Mn) are not well understood but may be influenced by neuroinflammatory activation of microglia and astrocytes that results in nitrosative stress due to expression of inducible nitric oxide synthase (iNOS/NOS2). We therefore postulated that gene deletion of NOS2 would protect against the neurotoxic effects of Mn in vivo and in vitro. Juvenile NOS2 knockout (NOS2(-/-)) mice were orally exposed to 50 mg/kg of MnCl₂ by intragastric gavage from days 21 to 34 postnatal. Results indicate that NOS2(-/-) mice exposed to Mn were protected against neurobehavioral alterations, despite histopathological activation of astrocytes and microglia in Mn-treated mice in both genotypes. NOS2(-/-) mice had decreased Mn-induced formation of 3-nitrotyrosine protein adducts within neurons in the basal ganglia that correlated with protection against Mn-induced neurobehavioral defects. Primary striatal astrocytes from wildtype mice caused apoptosis in cocultured striatal neurons following treatment with MnCl₂ and tumor necrosis factor-α, whereas NOS2(-/-) astrocytes failed to cause any increase in markers of apoptosis in striatal neurons. Additionally, scavenging nitric oxide (NO) with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO) prevented the ability of Mn- and cytokine-treated wildtype astrocytes to cause apoptosis in cocultured striatal neurons. These data demonstrate that NO plays a crucial role in Mn-induced neurological dysfunction in juvenile mice and that NOS2 expression in activated glia is an important mediator of neuroinflammatory injury during Mn exposure.
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Affiliation(s)
| | | | | | | | - Ronald B. Tjalkens
- Center for Environmental Medicine, Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado 80523-1680
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Montezuma K, Biojone C, Lisboa SF, Cunha FQ, Guimarães FS, Joca SRL. Inhibition of iNOS induces antidepressant-like effects in mice: pharmacological and genetic evidence. Neuropharmacology 2011; 62:485-91. [PMID: 21939674 DOI: 10.1016/j.neuropharm.2011.09.004] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 08/31/2011] [Accepted: 09/06/2011] [Indexed: 12/13/2022]
Abstract
Recent evidence has suggested that systemic administration of non-selective NOS inhibitors induces antidepressant-like effects in animal models. However, the precise involvement of the different NOS isoforms (neuronal-nNOS and inducible-iNOS) in these effects has not been clearly defined yet. Considering that mediators of the inflammatory response, that are able to induce iNOS expression, can be increased by exposure to stress, the aim of the present study was to investigate iNOS involvement in stress-induced behavioral consequences in the forced swimming test (FST), an animal model sensitive to antidepressant drugs. Therefore, we investigated the effects induced by systemic injection of aminoguanidine (preferential iNOS inhibitor), 1400W (selective iNOS inhibitor) or n-propyl-l-arginine (NPA, selective nNOS inhibitor) in mice submitted to the FST. We also investigated the behavior of mice with genetic deletion of iNOS (knockout) submitted to the FST. Aminoguanidine significantly decreased the immobility time (IT) in the FST. 1400W but not NPA, when administered at equivalent doses considering the magnitude of their Ki values for iNOS and nNOS, respectively, reduced the IT, thus suggesting that aminoguanidine-induced effects would be due to selective iNOS inhibition. Similarly, iNOS KO presented decreased IT in the FST when compared to wild-type mice. These results are the first to show that selective inhibition of iNOS or its knockdown induces antidepressant-like effects, therefore suggesting that iNOS-mediated NO synthesis is involved in the modulation of stress-induced behavioral consequences. Moreover, they further support NO involvement in the neurobiology of depression. This article is part of a Special Issue entitled 'Anxiety and Depression'.
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Affiliation(s)
- Karina Montezuma
- Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Brazil
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31
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Amitai Y. Physiologic role for "inducible" nitric oxide synthase: a new form of astrocytic-neuronal interface. Glia 2011; 58:1775-81. [PMID: 20737473 DOI: 10.1002/glia.21057] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Nitric oxide (NO) has been long recognized as an atypical neuronal messenger affecting excitatory synaptic transmission, but its cellular source has remained unresolved as the neuronal isoform of NO synthase (nNOS) in many brain regions is expressed only by small subsets of inhibitory neurons. It is generally believed that the glial NO-producing isoform (iNOS) is not expressed in the normal brain, but rather it undergoes a transcription-mediated up-regulation following an immunological challenge. Therefore, the involvement of iNOS in modulating normal neuronal functions has been largely ignored. Here I review evidence to the contrary: I summarize data pointing to the existence of a functioning iNOS in normal undisturbed mammalian brains, and experimental results tracing this expression to astrocytes. Finally, I review recent findings asserting that iNOS-dependent NO modulates synaptic release from presynaptic terminals. Based on these data, I propose that astrocytes express basal levels of iNOS. Flanking synaptic elements, astrocytes are perfectly positioned to release NO and affect synaptic transmission.
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Affiliation(s)
- Yael Amitai
- Department of Physiology and Neurobiology, Faculty of Health Sciences, Ben-Gurion University, Beer-Sheva, Israel.
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Buskila Y, Amitai Y. Astrocytic iNOS-dependent enhancement of synaptic release in mouse neocortex. J Neurophysiol 2010; 103:1322-8. [PMID: 20071630 DOI: 10.1152/jn.00676.2009] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Nitric oxide (NO) has been recognized as an atypical neuronal messenger affecting synaptic transmission, but its cellular source has remained unresolved as the neuronal NO synthase isoform (nNOS) in brain areas such as the neocortex is expressed only by a small subset of inhibitory neurons. The involvement of the glial NOS isoform (iNOS) in modulating neuronal activity has been largely ignored because it has been accepted that this enzyme is regulated by gene induction following detrimental stimuli. Using acute brain slices from mouse neocortex and electrophysiology, we found that selective inhibition of iNOS reduced both spontaneous and evoked synaptic release. Moreover, iNOS inhibition partially prevented and reversed the potentiation of excitatory synapses in layer 2/3 pyramidal neurons. NOS enzymatic assay confirmed a small but reliable Ca(2+)-independent activity fraction, consistent with the existence of functioning iNOS in the tissue. Together these data point to astrocytes as a source for the nitrosative regulation of synaptic release in the neocortex.
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Affiliation(s)
- Yossi Buskila
- Dept. of Physiology, Zlotowski Center for Neuroscience, Faculty of Health Sciences, Ben-Gurion University, Beer-Sheva, Israel
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Abu-Ghanem Y, Cohen H, Buskila Y, Grauer E, Amitai Y. Enhanced stress reactivity in nitric oxide synthase type 2 mutant mice: Findings in support of astrocytic nitrosative modulation of behavior. Neuroscience 2008; 156:257-65. [DOI: 10.1016/j.neuroscience.2008.07.043] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Revised: 07/15/2008] [Accepted: 07/23/2008] [Indexed: 11/28/2022]
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