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Ma J, Subramaniam P, Yancey JR, Farrington AA, McGlade EC, Renshaw PF, Yurgelun-Todd DA. Elevated circulating soluble interleukin-2 receptor (sCD25) level is associated with prefrontal excitatory-inhibitory imbalance in individuals with chronic pain: A proton MRS study. Brain Behav Immun 2024; 120:1-9. [PMID: 38772429 PMCID: PMC11269041 DOI: 10.1016/j.bbi.2024.05.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Revised: 04/29/2024] [Accepted: 05/18/2024] [Indexed: 05/23/2024] Open
Abstract
Aberrant neuronal excitability in the anterior cingulate cortex (ACC) is implicated in cognitive and affective pain processing. Such excitability may be amplified by activated circulating immune cells, including T lymphocytes, that interact with the central nervous system. Here, we conducted a study of individuals with chronic pain using magnetic resonance spectroscopy (MRS) to investigate the clinical evidence for the interaction between peripheral immune activation and prefrontal excitatory-inhibitory imbalance. In thirty individuals with chronic musculoskeletal pain, we assessed markers of peripheral immune activation, including soluble interleukin-2 receptor alpha chain (sCD25) levels, as well as brain metabolites, including Glx (glutamate + glutamine) to GABA+ (γ-aminobutyric acid + macromolecules/homocarnosine) ratio in the ACC. We found that the circulating level of sCD25 was associated with prefrontal Glx/GABA+. Greater prefrontal Glx/GABA+ was associated with higher pain catastrophizing, evaluative pain ratings, and anxiodepressive symptoms. Further, the interaction effect of sCD25 and prefrontal Glx/GABA+ on pain catastrophizing was significant, indicating the joint association of these two markers with pain catastrophizing. Our results provide the first evidence suggesting that peripheral T cellular activation, as reflected by elevated circulating sCD25 levels, may be linked to prefrontal excitatory-inhibitory imbalance in individuals with chronic pain. The interaction between these two systems may play a role as a potential mechanism underlying pain catastrophizing. Further prospective and treatment studies are needed to elucidate the specific role of the immune and brain interaction in pain catastrophizing.
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Affiliation(s)
- Jiyoung Ma
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, UT, USA; Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Punitha Subramaniam
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, UT, USA; Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - James R Yancey
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, UT, USA; Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, UT, USA; George E. Wahlen Department of Veterans Affairs Medical Center, VISN 19 Mental Illness Research, Education and Clinical Center, Salt Lake City, UT, USA
| | - Amy A Farrington
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, UT, USA; Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Erin C McGlade
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, UT, USA; Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, UT, USA; George E. Wahlen Department of Veterans Affairs Medical Center, VISN 19 Mental Illness Research, Education and Clinical Center, Salt Lake City, UT, USA
| | - Perry F Renshaw
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, UT, USA; Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, UT, USA; George E. Wahlen Department of Veterans Affairs Medical Center, VISN 19 Mental Illness Research, Education and Clinical Center, Salt Lake City, UT, USA
| | - Deborah A Yurgelun-Todd
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, UT, USA; Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, UT, USA; George E. Wahlen Department of Veterans Affairs Medical Center, VISN 19 Mental Illness Research, Education and Clinical Center, Salt Lake City, UT, USA.
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Bou Sader Nehme S, Sanchez-Sarasua S, Adel R, Tuifua M, Ali A, Essawy AE, Abdel Salam S, Hleihel W, Boué-Grabot E, Landry M. P2X4 signalling contributes to hyperactivity but not pain sensitization comorbidity in a mouse model of attention deficit/hyperactivity disorder. Front Pharmacol 2024; 14:1288994. [PMID: 38239187 PMCID: PMC10794506 DOI: 10.3389/fphar.2023.1288994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 12/12/2023] [Indexed: 01/22/2024] Open
Abstract
Introduction: Attention deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder characterized by hyperactivity, inattention, and impulsivity that often persist until adulthood. Frequent comorbid disorders accompany ADHD and two thirds of children diagnosed with ADHD also suffer from behavioural disorders and from alteration of sensory processing. We recently characterized the comorbidity between ADHD-like symptoms and pain sensitisation in a pharmacological mouse model of ADHD, and we demonstrated the implication of the anterior cingulate cortex and posterior insula. However, few studies have explored the causal mechanisms underlying the interactions between ADHD and pain. The implication of inflammatory mechanisms has been suggested but the signalling pathways involved have not been explored. Methods: We investigated the roles of purinergic signalling, at the crossroad of pain and neuroinflammatory pathways, by using a transgenic mouse line that carries a total deletion of the P2X4 receptor. Results: We demonstrated that P2X4 deletion prevents hyperactivity in the mouse model of ADHD. In contrast, the absence of P2X4 lowered thermal pain thresholds in sham conditions and did not affect pain sensitization in ADHD-like conditions. We further analysed microglia reactivity and the expression of inflammatory markers in wild type and P2X4KO mice. Our results revealed that P2X4 deletion limits microglia reactivity but at the same time exerts proinflammatory effects in the anterior cingulate cortex and posterior insula. Conclusion: This dual role of P2X4 could be responsible for the differential effects noted on ADHD-like symptoms and pain sensitization and calls for further studies to investigate the therapeutic benefit of targeting the P2X4 receptor in ADHD patients.
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Affiliation(s)
- Sarah Bou Sader Nehme
- University of Bordeaux, CNRS, Institute of Neurodegenerative Diseases, IMN, UMR 5293, Bordeaux, France
- Department of Biology, Faculty of Arts and Sciences, Holy Spirit University of Kaslik, Jounieh, Lebanon
| | - Sandra Sanchez-Sarasua
- University of Bordeaux, CNRS, Institute of Neurodegenerative Diseases, IMN, UMR 5293, Bordeaux, France
- Faculty of Health Sciences, University of Jaume I, Castellon, Spain
| | - Ramy Adel
- Zoology Department, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Marie Tuifua
- University of Bordeaux, CNRS, Institute of Neurodegenerative Diseases, IMN, UMR 5293, Bordeaux, France
| | - Awatef Ali
- Zoology Department, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Amina E. Essawy
- Zoology Department, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Sherine Abdel Salam
- Zoology Department, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Walid Hleihel
- Department of Biology, Faculty of Arts and Sciences, Holy Spirit University of Kaslik, Jounieh, Lebanon
| | - Eric Boué-Grabot
- University of Bordeaux, CNRS, Institute of Neurodegenerative Diseases, IMN, UMR 5293, Bordeaux, France
| | - Marc Landry
- University of Bordeaux, CNRS, Institute of Neurodegenerative Diseases, IMN, UMR 5293, Bordeaux, France
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Chen Y, Zhang Y, Lin W, Tang Y, Chen L, Gao Y, Gao G, Luo X, Chen A, Lin C. Role of magnesium-L-Threonate in alleviating skin/muscle incision and retraction induced mechanical allodynia and anxiodepressive-like behaviors in male rats. Brain Res 2023; 1817:148476. [PMID: 37406874 DOI: 10.1016/j.brainres.2023.148476] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 06/29/2023] [Accepted: 07/02/2023] [Indexed: 07/07/2023]
Abstract
Chronic postsurgical pain (CPSP) and its emotional comorbidities poses health burden to patients who have received the surgical treatment. However, its underlying mechanism remains unclear. Emerging studies indicate that magnesium deficiency is associated with neurological diseases, and magnesium supplement confers protection under these disease conditions. In this study, we examined the role and mechanism of magnesium deficiency in the pathology of surgery-induced allodynia and negative emotion using a rat model of skin/muscle incision and retraction (SMIR) and investigated the therapeutic effects of magnesium supplementation by oral magnesium-L-Threonate (L-TAMS) in SMIR-injured rats. In the SMIR model, rats developed mechanical allodynia and anxiodepressive-like behaviors. Further, SMIR caused microglia and astrocyte activation and enhanced expression of pro-inflammatory cytokine (TNF-α, IL-1β and IL-6) in the anterior cingulate cortex (ACC). Importantly, magnesium ion (Mg2+) levels decreased in the serum and cerebrospinal fluid (CSF) of SMIR-injured rats, which exhibited high correlation with pain and emotion behavioral phenotypes in these rats. Repeated oral administration of L-TAMS increased serum and CSF levels of Mg2+ in SMIR-injured rats. Notably, L-TAMS administration reversed SMIR-induced mechanical allodynia and anxiodepressive-like behaviors but did not affect pain and emotional behaviors in sham rats. Moreover, L-TAMS administration suppressed SMIR-caused glial activation and proinflammatory cytokine expression in the ACC but had no such effect in sham rats. Together, our study demonstrates the contributing role of magnesium deficiency in the pathology of surgery-induced chronic pain and negative emotion. Moreover, we suggest that L-TAMS might be a novel approach to treat CPSP and its emotional comorbidities.
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Affiliation(s)
- Yu Chen
- Pain Research Institute, Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, China
| | - Yimeng Zhang
- Pain Research Institute, Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, China
| | - Wei Lin
- Pain Research Institute, Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, China; Department of Pediatrics, The First Affiliated Hospital of Fujian Medical University, China
| | - Ying Tang
- Pain Research Institute, Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, China
| | - Liang Chen
- Pain Research Institute, Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, China
| | - Ying Gao
- Pain Research Institute, Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, China
| | - Guangcheng Gao
- Pain Research Institute, Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, China
| | - Xin Luo
- Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, China.
| | - Aiqin Chen
- Pain Research Institute, Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, China.
| | - Chun Lin
- Pain Research Institute, Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, China; Department of Pediatrics, The First Affiliated Hospital of Fujian Medical University, China.
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Silva-Cardoso GK, Lazarini-Lopes W, Primini EO, Hallak JE, Crippa JA, Zuardi AW, Garcia-Cairasco N, Leite-Panissi CRA. Cannabidiol modulates chronic neuropathic pain aversion behavior by attenuation of neuroinflammation markers and neuronal activity in the corticolimbic circuit in male Wistar rats. Behav Brain Res 2023; 452:114588. [PMID: 37474023 DOI: 10.1016/j.bbr.2023.114588] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/26/2023] [Accepted: 07/16/2023] [Indexed: 07/22/2023]
Abstract
Chronic neuropathic pain (CNP) is a vast world health problem often associated with the somatosensory domain. This conceptualization is problematic because, unlike most other sensations that are usually affectively neutral and may present emotional, affective, and cognitive impairments. Neuronal circuits that modulate pain can increase or decrease painful sensitivity based on several factors, including context and expectation. The objective of this study was to evaluate whether subchronic treatment with Cannabidiol (CBD; 0.3, 3, and 10 mg/kg intraperitoneal route - i.p., once a day for 3 days) could promote pain-conditioned reversal, in the conditioned place preference (CPP) test, in male Wistar rats submitted to chronic constriction injury (CCI) of the sciatic nerve. Then, we evaluated the expression of astrocytes and microglia in animals treated with CBD through the immunofluorescence technique. Our results demonstrated that CBD promoted the reversal of CPP at 3 and 10 mg/kg. In CCI animals, CBD was able to attenuate the increase in neuronal hyperactivity, measured by FosB protein expression, in the regions of the corticolimbic circuit: anterior cingulate cortex (ACC), complex basolateral amygdala (BLA), granular layer of the dentate gyrus (GrDG), and dorsal hippocampus (DH) - adjacent to subiculum (CA1). CBD also prevented the increased expression of GFAP and IBA-1 in CCI animals. We concluded that CBD effects on CNP are linked to the modulation of the aversive component of pain. These effects decrease chronic neuronal activation and inflammatory markers in regions of the corticolimbic circuit.
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Affiliation(s)
- Gleice K Silva-Cardoso
- Department of Psychology, School of Philosophy, Science and Letters of Ribeirão Preto, University of São Paulo, Brazil; National Institute for Translational Medicine (INCT-TM; CNPq), São Paulo, Brazil
| | - Willian Lazarini-Lopes
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Brazil; Department of Pharmacology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP 14049-900, Brazil
| | - Eduardo Octaviano Primini
- Department of Psychology, School of Philosophy, Science and Letters of Ribeirão Preto, University of São Paulo, Brazil
| | - Jaime E Hallak
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Brazil; National Institute for Translational Medicine (INCT-TM; CNPq), São Paulo, Brazil
| | - José A Crippa
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Brazil; National Institute for Translational Medicine (INCT-TM; CNPq), São Paulo, Brazil
| | - Antônio W Zuardi
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Brazil; National Institute for Translational Medicine (INCT-TM; CNPq), São Paulo, Brazil
| | - Norberto Garcia-Cairasco
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Brazil; Department of Physiology, Ribeirão Preto School of Medicine, University of São Paulo, Brazil
| | - Christie R A Leite-Panissi
- Department of Psychology, School of Philosophy, Science and Letters of Ribeirão Preto, University of São Paulo, Brazil; National Institute for Translational Medicine (INCT-TM; CNPq), São Paulo, Brazil.
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5
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Mussetto V, Moen A, Trofimova L, Sandkühler J, Hogri R. Differential activation of spinal and parabrachial glial cells in a neuropathic pain model. Front Cell Neurosci 2023; 17:1163171. [PMID: 37082205 PMCID: PMC10110840 DOI: 10.3389/fncel.2023.1163171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 03/17/2023] [Indexed: 04/22/2023] Open
Abstract
The clinical burden faced by chronic pain patients is compounded by affective comorbidities, such as depression and anxiety disorders. Emerging evidence suggests that reactive glial cells in the spinal cord dorsal horn play a key role in the chronification of pain, while supraspinal glia are important for psychological aspects of chronic pain. The lateral parabrachial nucleus (LPBN) in the brainstem is a key node in the ascending pain system, and is crucial for the emotional dimension of pain. Yet, whether astrocytes and microglia in the LPBN are activated during chronic pain is unknown. Here, we evaluated the occurrence of glial activation in the LPBN of male Sprague-Dawley rats 1, 4, and 7 weeks after inducing a chronic constriction injury (CCI) of the sciatic nerve, a prevalent neuropathic pain model. CCI animals developed mechanical and thermal hypersensitivity that persisted for at least 4 weeks, and was mostly reversed after 7 weeks. Using immunohistochemical staining and confocal imaging, we found that CCI caused a strong increase in the expression of the astrocytic marker GFAP and the microglial marker Iba1 in the ipsilateral spinal dorsal horn, with peak expression observed 1 week post-injury. Moreover, morphology analysis revealed changes in microglial phenotype, indicative of microglia activation. In contrast, CCI did not induce any detectable changes in either astrocytes or microglia in the LPBN, at any time point. Thus, our results indicate that while neuropathic pain induces a robust glial reaction in the spinal dorsal horn, it fails to activate glial cells in the LPBN.
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Affiliation(s)
| | | | | | | | - Roni Hogri
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
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6
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Castany S, Bagó-Mas A, Vela JM, Verdú E, Bretová K, Svobodová V, Dubový P, Boadas-Vaello P. Transient Reflexive Pain Responses and Chronic Affective Nonreflexive Pain Responses Associated with Neuroinflammation Processes in Both Spinal and Supraspinal Structures in Spinal Cord-Injured Female Mice. Int J Mol Sci 2023; 24:ijms24021761. [PMID: 36675275 PMCID: PMC9863935 DOI: 10.3390/ijms24021761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/10/2023] [Accepted: 01/14/2023] [Indexed: 01/18/2023] Open
Abstract
Central neuropathic pain is not only characterized by reflexive pain responses, but also emotional or affective nonreflexive pain responses, especially in women. Some pieces of evidence suggest that the activation of the neuroimmune system may be contributing to the manifestation of mood disorders in patients with chronic pain conditions, but the mechanisms that contribute to the development and chronicity of CNP and its associated disorders remain poorly understood. This study aimed to determine whether neuroinflammatory factor over-expression in the spinal cord and supraspinal structures may be associated with reflexive and nonreflexive pain response development from acute SCI phase to 12 weeks post-injury in female mice. The results show that transient reflexive responses were observed during the SCI acute phase associated with transient cytokine overexpression in the spinal cord. In contrast, increased nonreflexive pain responses were observed in the chronic phase associated with cytokine overexpression in supraspinal structures, especially in mPFC. In addition, results revealed that besides cytokines, the mPFC showed an increased glial activation as well as CX3CL1/CX3CR1 upregulation in the neurons, suggesting the contribution of neuron-glia crosstalk in the development of nonreflexive pain responses in the chronic spinal cord injury phase.
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Affiliation(s)
- Sílvia Castany
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, University of Girona, 17003 Girona, Catalonia, Spain
| | - Anna Bagó-Mas
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, University of Girona, 17003 Girona, Catalonia, Spain
- Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
| | - José Miguel Vela
- WeLab Barcelona, Parc Científic de Barcelona, 08028 Barcelona, Catalonia, Spain
| | - Enrique Verdú
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, University of Girona, 17003 Girona, Catalonia, Spain
| | - Karolina Bretová
- Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
| | - Viktorie Svobodová
- Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
| | - Petr Dubový
- Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
| | - Pere Boadas-Vaello
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, University of Girona, 17003 Girona, Catalonia, Spain
- Correspondence:
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Malange KF, Navia-Pelaez JM, Dias EV, Lemes JBP, Choi SH, Dos Santos GG, Yaksh TL, Corr M. Macrophages and glial cells: Innate immune drivers of inflammatory arthritic pain perception from peripheral joints to the central nervous system. FRONTIERS IN PAIN RESEARCH 2022; 3:1018800. [PMID: 36387416 PMCID: PMC9644179 DOI: 10.3389/fpain.2022.1018800] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 10/03/2022] [Indexed: 07/22/2023] Open
Abstract
Millions of people suffer from arthritis worldwide, consistently struggling with daily activities due to debilitating pain evoked by this disease. Perhaps the most intensively investigated type of inflammatory arthritis is rheumatoid arthritis (RA), where, despite considerable advances in research and clinical management, gaps regarding the neuroimmune interactions that guide inflammation and chronic pain in this disease remain to be clarified. The pain and inflammation associated with arthritis are not isolated to the joints, and inflammatory mechanisms induced by different immune and glial cells in other tissues may affect the development of chronic pain that results from the disease. This review aims to provide an overview of the state-of-the-art research on the roles that innate immune, and glial cells play in the onset and maintenance of arthritis-associated pain, reviewing nociceptive pathways from the joint through the dorsal root ganglion, spinal circuits, and different structures in the brain. We will focus on the cellular mechanisms related to neuroinflammation and pain, and treatments targeting these mechanisms from the periphery and the CNS. A comprehensive understanding of the role these cells play in peripheral inflammation and initiation of pain and the central pathways in the spinal cord and brain will facilitate identifying new targets and pathways to aide in developing therapeutic strategies to treat joint pain associated with RA.
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Affiliation(s)
- Kaue Franco Malange
- Department of Anesthesiology, University of California, San Diego, CA, United States
| | | | - Elayne Vieira Dias
- Department of Neurology, University of California, San Francisco, CA, United States
| | | | - Soo-Ho Choi
- Department of Medicine, University of California, San Diego, CA, United States
| | | | - Tony L. Yaksh
- Department of Anesthesiology, University of California, San Diego, CA, United States
| | - Maripat Corr
- Department of Medicine, University of California, San Diego, CA, United States
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Michailidis V, Lidhar NK, Cho C, Martin LJ. Characterizing Sex Differences in Depressive-Like Behavior and Glial Brain Cell Changes Following Peripheral Nerve Injury in Mice. Front Behav Neurosci 2021; 15:758251. [PMID: 34776894 PMCID: PMC8586001 DOI: 10.3389/fnbeh.2021.758251] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 09/30/2021] [Indexed: 12/30/2022] Open
Abstract
Chronic pain and depression are intimately linked; the combination of the two leads to higher health care costs, lower quality of life, and worse treatment outcomes with both conditions exhibiting higher prevalence among women. In the current study, we examined the development of depressive-like behavior in male and female mice using the spared nerve injury (SNI) model of neuropathic pain. Males displayed increased immobility on the forced-swim test - a measure of depressive-like behavior - 2 weeks following injury, while females developed depressive-like behavior at 3-week. Since the pathogenesis of chronic pain and depression may involve overlapping mechanisms including the activation of microglial cells, we explored glial cell changes in brain regions associated with pain processing and affect. Immunohistochemical analyses revealed that microglial cells were more numerous in female SNI mice in the contralateral ventral anterior cingulate cortex (ACC), a brain region important for pain processing and affect behavior, 2-week following surgery. Microglial cell activation was not different between any of the groups for the dorsal ACC or nucleus accumbens. Analysis of astrocyte density did not reveal any significant changes in glial fibrillary acidic protein (GFAP) staining in the ACC or nucleus accumbens. Overall, the current study characterized peripheral nerve injury induced depression-like behavior in male and female mice, which may be associated with different patterns of glial cell activation in regions important for pain processing and affect.
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Affiliation(s)
- Vassilia Michailidis
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | - Navdeep K. Lidhar
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Chulmin Cho
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Loren J. Martin
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
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Tang J, Bair M, Descalzi G. Reactive Astrocytes: Critical Players in the Development of Chronic Pain. Front Psychiatry 2021; 12:682056. [PMID: 34122194 PMCID: PMC8192827 DOI: 10.3389/fpsyt.2021.682056] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 05/03/2021] [Indexed: 12/16/2022] Open
Abstract
Chronic pain is associated with long term plasticity of nociceptive pathways in the central nervous system. Astrocytes can profoundly affect synaptic function and increasing evidence has highlighted how altered astrocyte activity may contribute to the pathogenesis of chronic pain. In response to injury, astrocytes undergo a shift in form and function known as reactive astrogliosis, which affects their release of cytokines and gliotransmitters. These neuromodulatory substances have been implicated in driving the persistent changes in central nociceptive activity. Astrocytes also release lactate which neurons can use to produce energy during synaptic plasticity. Furthermore, recent research has provided insight into lactate's emerging role as a signaling molecule in the central nervous system, which may be involved in directly modulating neuronal and astrocytic activity. In this review, we present evidence for the involvement of astrocyte-derived tumor necrosis factor alpha in pain-associated plasticity, in addition to research suggesting the potential involvement of gliotransmitters D-serine and adenosine-5'-triphosphate. We also discuss work implicating astrocyte-neuron metabolic coupling, and the possible role of lactate, which has been sparsely studied in the context of chronic pain, in supporting pathological changes in central nociceptive activity.
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Affiliation(s)
| | | | - Giannina Descalzi
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
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10
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McIlwrath SL, Starr ME, High AE, Saito H, Westlund KN. Effect of acetyl-L-carnitine on hypersensitivity in acute recurrent caerulein-induced pancreatitis and microglial activation along the brain’s pain circuitry. World J Gastroenterol 2021; 27:794-814. [PMID: 33727771 PMCID: PMC7941858 DOI: 10.3748/wjg.v27.i9.794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 12/08/2020] [Accepted: 01/15/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Acute pancreatitis (AP) and recurring AP are serious health care problems causing excruciating pain and potentially lethal outcomes due to sepsis. The validated caerulein- (CAE) induced mouse model of acute/recurring AP produces secondary persistent hypersensitivity and anxiety-like behavioral changes for study.
AIM To determine efficacy of acetyl-L-carnitine (ALC) to reduce pain-related behaviors and brain microglial activation along the pain circuitry in CAE-pancreatitis.
METHODS Pancreatitis was induced with 6 hly intraperitoneal (i.p.) injections of CAE (50 µg/kg), 3 d a week for 6 wk in male C57BL/6J mice. Starting in week 4, mice received either vehicle or ALC until experiment’s end. Mechanical hyper-sensitivity was assessed with von Frey filaments. Heat hypersensitivity was determined with the hotplate test. Anxiety-like behavior was tested in week 6 using elevated plus maze and open field tests. Microglial activation in brain was quantified histologically by immunostaining for ionized calcium-binding adaptor molecule 1 (Iba1).
RESULTS Mice with CAE-induced pancreatitis had significantly reduced mechanical withdrawal thresholds and heat response latencies, indicating ongoing pain. Treatment with ALC attenuated inflammation-induced hypersensitivity, but hypersensitivity due to abdominal wall injury caused by repeated intraperitoneal injections persisted. Animals with pancreatitis displayed spontaneous anxiety-like behavior in the elevated plus maze compared to controls. Treatment with ALC resulted in increased numbers of rearing activity events, but time spent in “safety” was not changed. After all the abdominal injections, pancreata were translucent if excised at experiment’s end and opaque if excised on the subsequent day, indicative of spontaneous healing. Post mortem histopathological analysis performed on pancreas sections stained with Sirius Red and Fast Green identified wide-spread fibrosis and acinar cell atrophy in sections from mice with CAE-induced pancreatitis that was not rescued by treatment with ALC. Microglial Iba1 immunostaining was significantly increased in hippocampus, thalamus (intralaminar nuclei), hypothalamus, and amygdala of mice with CAE-induced pancreatitis compared to naïve controls but unchanged in the primary somatosensory cortex compared to naïves.
CONCLUSION CAE-induced pancreatitis caused increased pain-related behaviors, pancreatic fibrosis, and brain microglial changes. ALC alleviated CAE-induced mechanical and heat hypersensitivity but not abdominal wall injury-induced hypersensitivity caused by the repeated injections.
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Affiliation(s)
- Sabrina L McIlwrath
- Research Service, New Mexico Veterans Affairs Healthcare System, Albuquerque, NM 87108, United States
| | - Marlene E Starr
- Department of Surgery, University of Kentucky, Lexington, KY 40536, United States
| | - Abigail E High
- College of Liberal Arts, University of Texas, Austin, TX 78712, United States
| | - Hiroshi Saito
- Department of Surgery, University of Kentucky, Lexington, KY 40536, United States
| | - Karin N Westlund
- Research Service, New Mexico Veterans Affairs Healthcare System, Albuquerque, NM 87108, United States
- Department of Anesthesiology and Critical Care Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States
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11
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Xiao X, Ding M, Zhang YQ. Role of the Anterior Cingulate Cortex in Translational Pain Research. Neurosci Bull 2021; 37:405-422. [PMID: 33566301 PMCID: PMC7954910 DOI: 10.1007/s12264-020-00615-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 06/03/2020] [Indexed: 02/06/2023] Open
Abstract
As the most common symptomatic reason to seek medical consultation, pain is a complex experience that has been classified into different categories and stages. In pain processing, noxious stimuli may activate the anterior cingulate cortex (ACC). But the function of ACC in the different pain conditions is not well discussed. In this review, we elaborate the commonalities and differences from accumulated evidence by a variety of pain assays for physiological pain and pathological pain including inflammatory pain, neuropathic pain, and cancer pain in the ACC, and discuss the cellular receptors and signaling molecules from animal studies. We further summarize the ACC as a new central neuromodulation target for invasive and non-invasive stimulation techniques in clinical pain management. The comprehensive understanding of pain processing in the ACC may lead to bridging the gap in translational research between basic and clinical studies and to develop new therapies.
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Affiliation(s)
- Xiao Xiao
- Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, Ministry of Education; Institute of Science and Technology for Brain-Inspired Intelligence, Behavioral and Cognitive Neuroscience Center, Fudan University, Shanghai, 200433, China.
| | - Ming Ding
- Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, Ministry of Education; Institute of Science and Technology for Brain-Inspired Intelligence, Behavioral and Cognitive Neuroscience Center, Fudan University, Shanghai, 200433, China
| | - Yu-Qiu Zhang
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Department of Translational Neuroscience, Jing'an District Centre Hospital of Shanghai, Institutes of Brain Science; Institute of Integrative Medicine, Fudan University, Shanghai, 200032, China.
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12
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Kummer KK, Mitrić M, Kalpachidou T, Kress M. The Medial Prefrontal Cortex as a Central Hub for Mental Comorbidities Associated with Chronic Pain. Int J Mol Sci 2020; 21:E3440. [PMID: 32414089 PMCID: PMC7279227 DOI: 10.3390/ijms21103440] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/06/2020] [Accepted: 05/07/2020] [Indexed: 12/13/2022] Open
Abstract
Chronic pain patients frequently develop and suffer from mental comorbidities such as depressive mood, impaired cognition, and other significant constraints of daily life, which can only insufficiently be overcome by medication. The emotional and cognitive components of pain are processed by the medial prefrontal cortex, which comprises the anterior cingulate cortex, the prelimbic, and the infralimbic cortex. All three subregions are significantly affected by chronic pain: magnetic resonance imaging has revealed gray matter loss in all these areas in chronic pain conditions. While the anterior cingulate cortex appears hyperactive, prelimbic, and infralimbic regions show reduced activity. The medial prefrontal cortex receives ascending, nociceptive input, but also exerts important top-down control of pain sensation: its projections are the main cortical input of the periaqueductal gray, which is part of the descending inhibitory pain control system at the spinal level. A multitude of neurotransmitter systems contributes to the fine-tuning of the local circuitry, of which cholinergic and GABAergic signaling are particularly emerging as relevant components of affective pain processing within the prefrontal cortex. Accordingly, factors such as distraction, positive mood, and anticipation of pain relief such as placebo can ameliorate pain by affecting mPFC function, making this cortical area a promising target region for medical as well as psychosocial interventions for pain therapy.
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Affiliation(s)
| | | | | | - Michaela Kress
- Institute of Physiology, Medical University of Innsbruck, 6020 Innsbruck, Austria; (K.K.K.); (M.M.); (T.K.)
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13
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Naylor B, Hesam-Shariati N, McAuley JH, Boag S, Newton-John T, Rae CD, Gustin SM. Reduced Glutamate in the Medial Prefrontal Cortex Is Associated With Emotional and Cognitive Dysregulation in People With Chronic Pain. Front Neurol 2019; 10:1110. [PMID: 31849800 PMCID: PMC6903775 DOI: 10.3389/fneur.2019.01110] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 10/03/2019] [Indexed: 01/03/2023] Open
Abstract
A decrease in glutamate in the medial prefrontal cortex (mPFC) has been extensively found in animal models of chronic pain. Given that the mPFC is implicated in emotional appraisal, cognition and extinction of fear, could a potential decrease in glutamate be associated with increased pessimistic thinking, fear and worry symptoms commonly found in people with chronic pain? To clarify this question, 19 chronic pain subjects and 19 age- and gender-matched control subjects without pain underwent magnetic resonance spectroscopy. Both groups also completed the Temperament and Character, the Beck Depression and the State Anxiety Inventories to measure levels of harm avoidance, depression, and anxiety, respectively. People with chronic pain had significantly higher scores in harm avoidance, depression and anxiety compared to control subjects without pain. High levels of harm avoidance are characterized by excessive worry, pessimism, fear, doubt and fatigue. Individuals with chronic pain showed a significant decrease in mPFC glutamate levels compared to control subjects without pain. In people with chronic pain mPFC glutamate levels were significantly negatively correlated with harm avoidance scores. This means that the lower the concentration of glutamate in the mPFC, the greater the total scores of harm avoidance. High scores are associated with fearfulness, pessimism, and fatigue-proneness. We suggest that chronic pain, particularly the stress-induced release of glucocorticoids, induces changes in glutamate transmission in the mPFC, thereby influencing cognitive, and emotional processing. Thus, in people with chronic pain, regulation of fear, worry, negative thinking and fatigue is impaired.
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Affiliation(s)
- Brooke Naylor
- Neuroscience Research Australia, Sydney, NSW, Australia.,School of Psychology, Macquarie University, Sydney, NSW, Australia
| | | | - James H McAuley
- Neuroscience Research Australia, Sydney, NSW, Australia.,School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Simon Boag
- School of Psychology, Macquarie University, Sydney, NSW, Australia
| | - Toby Newton-John
- Graduate School of Health, University of Technology Sydney, Sydney, NSW, Australia
| | | | - Sylvia M Gustin
- Neuroscience Research Australia, Sydney, NSW, Australia.,School of Psychology, University of New South Wales, Sydney, NSW, Australia
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14
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He JH, Yu L, Wang ZY, Wang Q, Cao JL, Gu LB. Inhibition Of Monocarboxylate Transporter 1 In Spinal Cord Horn Significantly Reverses Chronic Inflammatory Pain. J Pain Res 2019; 12:2981-2990. [PMID: 31807055 PMCID: PMC6842320 DOI: 10.2147/jpr.s219359] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 10/19/2019] [Indexed: 12/15/2022] Open
Abstract
Purpose Chronic inflammatory pain is a common condition in the clinic, and the underlying mechanism is not being completely understood. Various studies have demonstrated that central and peripheral sensitization and synaptic plasticity could play crucial functions in chronic inflammatory pain. Moreover, families of monocarboxylate transporters (MCTs) are closely related to cellular metabolism and synaptic plasticity, and it is also reported that MCTs participate in chronic inflammatory pain. Nevertheless, there is a probability of the engaging role of MCT 1 is in chronic inflammatory pain, but its specific cellular level mechanism is yet to be investigated. In our study, we hypothesized that MCT 1 in the spinal dorsal horn plays an important part in chronic inflammatory pain. Methods In experiment A, rats were gone through nociceptive behavioral testing at 1 d day before and 1 d, 3 d, and 7 d after completing complete Freund’s adjuvant (CFA) injection. The specimens collected for detecting MCT 1 by Western blotting. In experiment B, rats were randomly divided into four groups. Intrathecal injection of MCT 1 inhibitor and nociceptive behavioral tests were performed 1 d day before and 1 d, 3 d, 7 d, 14 d, and 21 d after CFA injection. MCT 1 and p-ERK levels in spinal dorsal horn were measured by Western blotting, and GFAP in spinal dorsal horn was detected by immunofluorescence. Results The expression of MCT 1 in the spinal dorsal horn was increased during chronic inflammatory pain in rats. The intrathecal injection of an MCT 1 inhibitor evidently diminished the expression of MCT 1 and GFAP in the spinal dorsal horn, and the behavioral nociceptive responses were also attenuated. Meanwhile, the expression of p-ERK was also decreased by the intrathecal injection of an MCT 1 inhibitor. Conclusion Our results indicate that MCT 1 very likely play a critical role in regulating chronic inflammatory pain and may influence the regulation of synaptic plasticity via ERK in the spinal dorsal horn of rats.
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Affiliation(s)
- Jian-Hua He
- Department of Anesthesiology, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research and The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, People's Republic of China
| | - Ling Yu
- Department of Ultrasound, Affiliated Hospital of Integrate Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Jiangsu Province Academy of Traditional Chinese Medicine, Nanjing,People's Republic of China
| | - Zhi-Yong Wang
- Department of Anesthesiology, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research and The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, People's Republic of China
| | - Qiang Wang
- Department of Anesthesiology, Nanjing Meishan Hospital, Nanjing, People's Republic of China
| | - Jun-Li Cao
- Jiangsu Key Laboratory of Anesthesiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, People's Republic of China
| | - Lian-Bing Gu
- Department of Anesthesiology, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research and The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, People's Republic of China
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15
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Li T, Chen X, Zhang C, Zhang Y, Yao W. An update on reactive astrocytes in chronic pain. J Neuroinflammation 2019; 16:140. [PMID: 31288837 PMCID: PMC6615111 DOI: 10.1186/s12974-019-1524-2] [Citation(s) in RCA: 184] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 06/18/2019] [Indexed: 12/17/2022] Open
Abstract
Chronic pain is a critical clinical problem with an increasing prevalence. However, there are limited effective prevention measures and treatments for chronic pain. Astrocytes are the most abundant glial cells in the central nervous system and play important roles in both physiological and pathological conditions. Over the past few decades, a growing body of evidence indicates that astrocytes are involved in the regulation of chronic pain. Recently, reactive astrocytes were further classified into A1 astrocytes and A2 astrocytes according to their functions. After nerve injury, A1 astrocytes can secrete neurotoxins that induce rapid death of neurons and oligodendrocytes, whereas A2 astrocytes promote neuronal survival and tissue repair. These findings can well explain the dual effects of reactive astrocytes in central nervous injury and diseases. In this review, we will summarise the (1) changes in the morphology and function of astrocytes after noxious stimulation and nerve injury, (2) molecular regulators and signalling mechanisms involved in the activation of astrocytes and chronic pain, (3) the role of spinal and cortical astrocyte activation in chronic pain, and (4) the roles of different subtypes of reactive astrocytes (A1 and A2 phenotypes) in nerve injury that is associated with chronic pain. This review provides updated information on the role of astrocytes in the regulation of chronic pain. In particular, we discuss recent findings about A1 and A2 subtypes of reactive astrocytes and make several suggestions for potential therapeutic targets for chronic pain.
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Affiliation(s)
- Ting Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Xuhui Chen
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Chuanhan Zhang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yue Zhang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Wenlong Yao
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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16
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Moreno P, Cazuza RA, Mendes-Gomes J, Díaz AF, Polo S, Leánez S, Leite-Panissi CRA, Pol O. The Effects of Cobalt Protoporphyrin IX and Tricarbonyldichlororuthenium (II) Dimer Treatments and Its Interaction with Nitric Oxide in the Locus Coeruleus of Mice with Peripheral Inflammation. Int J Mol Sci 2019; 20:ijms20092211. [PMID: 31060340 PMCID: PMC6540196 DOI: 10.3390/ijms20092211] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 05/02/2019] [Indexed: 11/20/2022] Open
Abstract
Heme oxygenase 1 (HO-1) and carbon monoxide were shown to normalize oxidative stress and inflammatory reactions induced by neuropathic pain in the central nervous system, but their effects in the locus coeruleus (LC) of animals with peripheral inflammation and their interaction with nitric oxide are unknown. In wild-type (WT) and knockout mice for neuronal (NOS1-KO) or inducible (NOS2-KO) nitric oxide synthases with inflammatory pain induced by complete Freund’s adjuvant (CFA), we assessed: (1) antinociceptive actions of cobalt protoporphyrin IX (CoPP), an HO-1 inducer; (2) effects of CoPP and tricarbonyldichlororuthenium(II) dimer (CORM-2), a carbon monoxide-liberating compound, on the expression of HO-1, NOS1, NOS2, CD11b/c, GFAP, and mitogen-activated protein kinases (MAPK) in the LC. CoPP reduced inflammatory pain in different time-dependent manners in WT and KO mice. Peripheral inflammation activated astroglia in the LC of all genotypes and increased the levels of NOS1 and phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK 1/2) in WT mice. CoPP and CORM-2 enhanced HO-1 and inhibited astroglial activation in all genotypes. Both treatments blocked NOS1 overexpression, and CoPP normalized ERK 1/2 activation. This study reveals an interaction between HO-1 and NOS1/NOS2 during peripheral inflammation and shows that CoPP and CORM-2 improved HO-1 expression and modulated the inflammatory and/or plasticity changes caused by peripheral inflammation in the LC.
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Affiliation(s)
- Patricia Moreno
- Grup de Neurofarmacologia Molecular, Institutd'InvestigacióBiomèdicaSant Pau, Hospital de la Santa Creu i Sant Pau, 08025 Barcelona, Spain.
- Institut de Neurociències, UniversitatAutònoma de Barcelona, 08193 Barcelona, Spain.
| | - Rafael Alves Cazuza
- Department of Psychology, Faculty of Philosophy, Science and Letters, University of São Paulo, 14040-901, RibeirãoPreto, SP, Brazil.
| | - Joyce Mendes-Gomes
- Department of Psychology, Faculty of Philosophy, Science and Letters, University of São Paulo, 14040-901, RibeirãoPreto, SP, Brazil.
| | - Andrés Felipe Díaz
- Grup de Neurofarmacologia Molecular, Institutd'InvestigacióBiomèdicaSant Pau, Hospital de la Santa Creu i Sant Pau, 08025 Barcelona, Spain.
- Institut de Neurociències, UniversitatAutònoma de Barcelona, 08193 Barcelona, Spain.
| | - Sara Polo
- Grup de Neurofarmacologia Molecular, Institutd'InvestigacióBiomèdicaSant Pau, Hospital de la Santa Creu i Sant Pau, 08025 Barcelona, Spain.
- Institut de Neurociències, UniversitatAutònoma de Barcelona, 08193 Barcelona, Spain.
| | - Sergi Leánez
- Grup de Neurofarmacologia Molecular, Institutd'InvestigacióBiomèdicaSant Pau, Hospital de la Santa Creu i Sant Pau, 08025 Barcelona, Spain.
- Institut de Neurociències, UniversitatAutònoma de Barcelona, 08193 Barcelona, Spain.
| | | | - Olga Pol
- Grup de Neurofarmacologia Molecular, Institutd'InvestigacióBiomèdicaSant Pau, Hospital de la Santa Creu i Sant Pau, 08025 Barcelona, Spain.
- Institut de Neurociències, UniversitatAutònoma de Barcelona, 08193 Barcelona, Spain.
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17
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Yao PW, Wang SK, Chen SX, Xin WJ, Liu XG, Zang Y. Upregulation of tumor necrosis factor-alpha in the anterior cingulate cortex contributes to neuropathic pain and pain-associated aversion. Neurobiol Dis 2019; 130:104456. [PMID: 31028871 DOI: 10.1016/j.nbd.2019.04.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 04/10/2019] [Accepted: 04/23/2019] [Indexed: 10/26/2022] Open
Abstract
Injury associated pain involves subjective perception and emotional experience. The anterior cingulate cortex (ACC) is a key area involved in the affective component of pain processing. However, the neuroimmune mechanisms underlying enhanced ACC excitability following peripheral nerve injury are still not fully understood. Our previous work has shown that tumor necrosis factor-alpha (TNF-α) overexpression leads to peripheral afferent hyperexcitability and synaptic transmission potentiation in spinal cord. Here, we aimed to reveal the potential role of ACC TNF-α in ACC hyperexcitability and neuropathic pain. c-Fos, a widely used neuronal activity marker, was induced especially in contralateral ACC early [postoperative (PO) 1 h] and later (PO day 7 and 10) during the development of neuropathic pain. Spared nerve injury (SNI) elevated TNF-α level in contralateral ACC from PO day 5 to 14, delayed relative to decreased ipsilateral paw withdrawal threshold apparent from PO day 1 to 14. Microinjection of anti-TNF-α antibody into the ACC completely eliminated c-Fos overexpression and greatly attenuated pain aversion and mechanical allodynia induced by SNI, suggesting an important role of ACC TNF-α in the pain aversiveness and pain maintenance. Furthermore, modulating ACC pyramidal neurons via a Gi-coupled human M4 muscarinic receptor (hM4Di) or a Gq-coupled human M3 muscarinic receptor (hM3Dq), a type of designer receptors exclusively activated by designer drugs (DREADD), greatly changed the ACC TNF-α level and the mechanical paw withdrawal threshold. The positive interactions between TNF-α and ACC neurons might modulate the cytokine microenvironment thus contribute to the neuropathic pain.
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Affiliation(s)
- Pei-Wen Yao
- Pain Research Center and Department of Physiology, Zhongshan Medical School, Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, PR China
| | - Shao-Kun Wang
- Pain Research Center and Department of Physiology, Zhongshan Medical School, Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, PR China
| | - Shao-Xia Chen
- Pain Research Center and Department of Physiology, Zhongshan Medical School, Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, PR China; Department of Anesthesiology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, 651 Dongfeng Road East, Guangzhou 510060, PR China
| | - Wen-Jun Xin
- Pain Research Center and Department of Physiology, Zhongshan Medical School, Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, PR China
| | - Xian-Guo Liu
- Pain Research Center and Department of Physiology, Zhongshan Medical School, Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, PR China
| | - Ying Zang
- Pain Research Center and Department of Physiology, Zhongshan Medical School, Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, PR China.
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18
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Kang D, McAuley JH, Kassem MS, Gatt JM, Gustin SM. What does the grey matter decrease in the medial prefrontal cortex reflect in people with chronic pain? Eur J Pain 2018; 23:203-219. [PMID: 30101509 DOI: 10.1002/ejp.1304] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 08/05/2018] [Accepted: 08/07/2018] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND OBJECTIVE Alterations in the grey matter volume of several brain regions have been reported in people with chronic pain. The most consistent observation is a decrease in grey matter volume in the medial prefrontal cortex. These findings are important as the medial prefrontal cortex plays a critical role in emotional and cognitive processing in chronic pain. Although a logical cause of grey matter volume decrease may be neurodegeneration, this is not supported by the current evidence. Therefore, the purpose of this review was to evaluate the existing literature to unravel what the decrease in medial prefrontal cortex grey matter volume in people with chronic pain may represent on a biochemical and cellular level. DATABASES AND DATA TREATMENT A literature search for this topical review was conducted using PubMed and SCOPUS library. Search terms included chronic pain, pain, medial prefrontal cortex, anterior cingulate cortex, grey matter, neurochemistry, spectroscopy, magnetic resonance imaging, positron emission tomography, dendrite, neurodegeneration, glia, astrocyte, microglia, neurotransmitter, glutamate, GABA and different combinations of these terms. RESULTS Adopting a stress model of chronic pain, two major pathways are proposed that contribute to grey matter volume decrease in the medial prefrontal cortex: (a) changes in dendritic morphology as a result of hypothalamic-pituitary axis dysfunction and (b) neurotransmitter dysregulation, specifically glutamate and γ-Aminobutyric acid, which affects local microvasculature. CONCLUSION Our model proposes new mechanisms in chronic pain pathophysiology responsible for mPFC grey matter loss as alternatives to neurodegeneration. SIGNIFICANCE It is unclear what the decrease in medial prefrontal cortex grey matter volume represents in chronic pain. The most attractive reason is neurodegeneration. However, there is no evidence to support this. Our review reveals nondegenerative causes of decreased medial prefrontal grey matter to guide future research into chronic pain pathophysiology.
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Affiliation(s)
- David Kang
- Neuroscience Research Australia, Sydney, NSW, Australia.,UNSW Medicine, UNSW Sydney, Sydney, NSW, Australia
| | - James H McAuley
- Neuroscience Research Australia, Sydney, NSW, Australia.,UNSW Medicine, UNSW Sydney, Sydney, NSW, Australia
| | | | - Justine M Gatt
- Neuroscience Research Australia, Sydney, NSW, Australia.,School of Psychology, UNSW Sydney, Sydney, NSW, Australia
| | - Sylvia M Gustin
- Neuroscience Research Australia, Sydney, NSW, Australia.,School of Psychology, UNSW Sydney, Sydney, NSW, Australia
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19
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Eto K, Kim SK, Takeda I, Nabekura J. The roles of cortical astrocytes in chronic pain and other brain pathologies. Neurosci Res 2017; 126:3-8. [PMID: 28870605 DOI: 10.1016/j.neures.2017.08.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 08/01/2017] [Accepted: 08/18/2017] [Indexed: 01/21/2023]
Abstract
Astrocytes are the most abundant cell type in the brain. Several decades ago, they were considered to be only support cells in the central nervous system. Recent studies using advanced technologies have clarified that astrocytes play more active roles in regulating neuronal function and remodeling synaptic structures by releasing molecules called gliotransmitters. In addition to various physiological functions, astrocytes are activated under disease conditions, such as chronic pain, releasing molecules that in turn cause reorganization of the central nervous system microstructure and disrupt behavior in pathological conditions. In the present review, we summarize cortical astrocyte function in chronic pain and other neurological disorders and discuss the role of astrocytes in brain pathologies.
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Affiliation(s)
- Kei Eto
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki, Aichi 444-8585, Japan; Department of Physiological Sciences, The Graduate School for Advanced Studies, Hayama, Kanagawa 240-0193, Japan
| | - Sun Kwang Kim
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Ikuko Takeda
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki, Aichi 444-8585, Japan
| | - Junichi Nabekura
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki, Aichi 444-8585, Japan; Department of Physiological Sciences, The Graduate School for Advanced Studies, Hayama, Kanagawa 240-0193, Japan; Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Tokyo 102-0076, Japan.
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20
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Wang H, Sun X. Carbon Monoxide-Releasing Molecule-2 Inhibits Connexin 43-Hemichannel Activity in Spinal Cord Astrocytes to Attenuate Neuropathic Pain. J Mol Neurosci 2017; 63:58-69. [DOI: 10.1007/s12031-017-0957-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Accepted: 07/26/2017] [Indexed: 12/30/2022]
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21
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Miyamoto K, Kume K, Ohsawa M. Role of microglia in mechanical allodynia in the anterior cingulate cortex. J Pharmacol Sci 2017; 134:158-165. [PMID: 28669596 DOI: 10.1016/j.jphs.2017.05.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 05/12/2017] [Accepted: 05/22/2017] [Indexed: 01/06/2023] Open
Abstract
Plastic changes that increase nociceptive transmission are observed in several brain regions under conditions of chronic pain. Synaptic plasticity in the anterior cingulate cortex (ACC) is particularly associated with neuropathic pain. Glial cells are considered candidates for the modulation of neural plastic changes in the central nervous system. In this study, we aimed to investigate the role of ACC glial cells in the development of neuropathic pain. First, we examined the expression of glial cells in the ACC of nerve-ligated mice. The expression of astrocytes and microglia was increased in the ACC of nerve-ligated mice, which was reversed by intracerebroventricular (i.c.v) treatment with the microglia inhibitor minocycline. Then, we examined the effect of minocycline on mechanical allodynia in nerve-ligated mice. I.c.v. and intra-ACC treatment with minocycline partially inhibited mechanical allodynia in the nerve-ligated mice. The expression of phosphorylated alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor GluR1 subunit at Ser831, but not at Ser845, was increased in the ACC of the nerve-ligated mice compared to sham-operated mice, which was attenuated by minocycline administration. These results suggest that the activation of microglia in the ACC is involved in the development of hyperalgesia in mice with neuropathic pain.
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Affiliation(s)
- Keisuke Miyamoto
- Department of Neuropharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
| | - Kazuhiko Kume
- Department of Neuropharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
| | - Masahiro Ohsawa
- Department of Neuropharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan.
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Guo B, Wang J, Yao H, Ren K, Chen J, Yang J, Cai G, Liu H, Fan Y, Wang W, Wu S. Chronic Inflammatory Pain Impairs mGluR5-Mediated Depolarization-Induced Suppression of Excitation in the Anterior Cingulate Cortex. Cereb Cortex 2017; 28:2118-2130. [DOI: 10.1093/cercor/bhx117] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Indexed: 11/13/2022] Open
Affiliation(s)
- Baolin Guo
- Department of Neurobiology and Collaborative Innovation Center for Brain Science, School of Basic Medicine, Fourth Military Medical University, Xi’an 710032, P.R. China
| | - Jiaqi Wang
- Cadet Brigade, Fourth Military Medical University, Xi’an 710032, P.R. China
| | - Han Yao
- Department of Neurobiology and Collaborative Innovation Center for Brain Science, School of Basic Medicine, Fourth Military Medical University, Xi’an 710032, P.R. China
| | - Keke Ren
- School of life Sciences, Yan’an University, Yan’an 716000, P.R. China
| | - Jing Chen
- Department of Anatomy and K.K. Leung Brain Research Centre, Fourth Military Medical University, Xi’an 710032, P.R. China
| | - Jing Yang
- Department of Neurobiology and Collaborative Innovation Center for Brain Science, School of Basic Medicine, Fourth Military Medical University, Xi’an 710032, P.R. China
| | - Guohong Cai
- Department of Neurobiology and Collaborative Innovation Center for Brain Science, School of Basic Medicine, Fourth Military Medical University, Xi’an 710032, P.R. China
| | - Haiying Liu
- Cadet Brigade, Fourth Military Medical University, Xi’an 710032, P.R. China
| | - Yunlong Fan
- Cadet Brigade, Fourth Military Medical University, Xi’an 710032, P.R. China
| | - Wenting Wang
- Department of Neurobiology and Collaborative Innovation Center for Brain Science, School of Basic Medicine, Fourth Military Medical University, Xi’an 710032, P.R. China
| | - Shengxi Wu
- Department of Neurobiology and Collaborative Innovation Center for Brain Science, School of Basic Medicine, Fourth Military Medical University, Xi’an 710032, P.R. China
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23
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Tsuda M, Koga K, Chen T, Zhuo M. Neuronal and microglial mechanisms for neuropathic pain in the spinal dorsal horn and anterior cingulate cortex. J Neurochem 2017; 141:486-498. [DOI: 10.1111/jnc.14001] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 02/02/2017] [Accepted: 02/08/2017] [Indexed: 01/02/2023]
Affiliation(s)
- Makoto Tsuda
- Department of Life Innovation; Graduate School of Pharmaceutical Sciences; Kyushu University; Fukuoka Japan
| | - Kohei Koga
- Department of Neurophysiology; Hirosaki University Graduate School of Medicine; Hirosaki Japan
- Department of Physiology; University of Toronto; Toronto Canada
| | - Tao Chen
- Department of Physiology; University of Toronto; Toronto Canada
- Department of Anatomy, Histology and Embryology; Fourth Military Medical University; Xi'an Shaanxi China
- Center for Neuron and Disease; Frontier Institutes of Science and Technology; Xi'an Jiaotong University; Xi'an Shanxi China
| | - Min Zhuo
- Department of Physiology; University of Toronto; Toronto Canada
- Center for Neuron and Disease; Frontier Institutes of Science and Technology; Xi'an Jiaotong University; Xi'an Shanxi China
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Inhibition of the cAMP/PKA/CREB Pathway Contributes to the Analgesic Effects of Electroacupuncture in the Anterior Cingulate Cortex in a Rat Pain Memory Model. Neural Plast 2016; 2016:5320641. [PMID: 28090359 PMCID: PMC5206448 DOI: 10.1155/2016/5320641] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 09/30/2016] [Accepted: 10/24/2016] [Indexed: 12/20/2022] Open
Abstract
Pain memory is considered as endopathic factor underlying stubborn chronic pain. Our previous study demonstrated that electroacupuncture (EA) can alleviate retrieval of pain memory. This study was designed to observe the different effects between EA and indomethacin (a kind of nonsteroid anti-inflammatory drugs, NSAIDs) in a rat pain memory model. To explore the critical role of protein kinase A (PKA) in pain memory, a PKA inhibitor was microinjected into anterior cingulate cortex (ACC) in model rats. We further investigated the roles of the cyclic adenosine monophosphate (cAMP), PKA, cAMP response element-binding protein (CREB), and cAMP/PKA/CREB pathway in pain memory to explore the potential molecular mechanism. The results showed that EA alleviates the retrieval of pain memory while indomethacin failed. Intra-ACC microinjection of a PKA inhibitor blocked the occurrence of pain memory. EA reduced the activation of cAMP, PKA, and CREB and the coexpression levels of cAMP/PKA and PKA/CREB in the ACC of pain memory model rats, but indomethacin failed. The present findings identified a critical role of PKA in ACC in retrieval of pain memory. We propose that the proper mechanism of EA on pain memory is possibly due to the partial inhibition of cAMP/PKA/CREB signaling pathway by EA.
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25
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Abstract
Repeated administration of peroxisome proliferator-activated receptor gamma (PPARγ) agonists reduces neuropathic pain-like behavior and associated changes in glial activation in the spinal cord dorsal horn. As PPARγ is a nuclear receptor, sustained changes in gene expression are widely believed to be the mechanism of pain reduction. However, we recently reported that a single intrathecal (i.t.) injection of pioglitazone, a PPARγ agonist, reduced hyperalgesia within 30 minutes, a time frame that is typically less than that required for genomic mechanisms. To determine the very rapid antihyperalgesic actions of PPARγ activation, we administered pioglitazone to rats with spared nerve injury and evaluated hyperalgesia. Pioglitazone inhibited hyperalgesia within 5 minutes of injection, consistent with a nongenomic mechanism. Systemic or i.t. administration of GW9662, a PPARγ antagonist, inhibited the antihyperalgesic actions of intraperitoneal or i.t. pioglitazone, suggesting a spinal PPARγ-dependent mechanism. To further address the contribution of nongenomic mechanisms, we blocked new protein synthesis in the spinal cord with anisomycin. When coadministered intrathecally, anisomycin did not change pioglitazone antihyperalgesia at an early 7.5-minute time point, further supporting a rapid nongenomic mechanism. At later time points, anisomycin reduced pioglitazone antihyperalgesia, suggesting delayed recruitment of genomic mechanisms. Pioglitazone reduction of spared nerve injury-induced increases in GFAP expression occurred more rapidly than expected, within 60 minutes. We are the first to show that activation of spinal PPARγ rapidly reduces neuropathic pain independent of canonical genomic activity. We conclude that acute pioglitazone inhibits neuropathic pain in part by reducing astrocyte activation and through both genomic and nongenomic PPARγ mechanisms.
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Electroacupuncture alleviates retrieval of pain memory and its effect on phosphorylation of cAMP response element-binding protein in anterior cingulate cortex in rats. Behav Brain Funct 2015; 11:9. [PMID: 25886521 PMCID: PMC4364627 DOI: 10.1186/s12993-015-0055-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 02/16/2015] [Indexed: 12/11/2022] Open
Abstract
Background Recent evidence suggests that persistent pain and recurrent pain are due to the pain memory which is related to the phosphorylation of cAMP response element-binding protein (p-CREB) in anterior cingulate cortex (ACC). Eletroacupuncture (EA), as a complementary Chinese medical procedure, has a significant impact on the treatment of pain and is now considered as a mind-body therapy. Methods The rat model of pain memory was induced by two injections of carrageenan into the paws, which was administered separately by a 14-day interval, and treated with EA therapy. The paw withdrawal thresholds (PWTs) of animals were measured and p-CREB expressions in ACC were detected by using immunofluorescence (IF) and electrophoretic mobility shift assay (EMSA). Statistical comparisons among different groups were made by one-way, repeated-measures analysis of variance (ANOVA). Results The second injection of carrageenan caused the decrease of PWTs in the non-injected hind paw. EA stimulation applied prior to the second injection, increased the values of PWTs. In ACC, the numbers of p-CREB positive cells were significantly increased in pain memory model rats, which were significantly reduced by EA. EMSA results showed EA also down-regulated the combining capacity of p-CREB with its DNA. Furthermore, the co-expression of p-CREB with GFAP, OX-42, or NeuN in ACC was strengthened in the pain memory model rats. EA inhibited the co-expression of p-CREB with GFAP or OX-42, but not NeuN in ACC. Conclusions The present results suggest the retrieval of pain memory could be alleviated by the pre-treatment of EA, which is at least partially attributed to the down-regulated expression and combining capacity of p-CREB and the decreased expression of p-CREB in astrocytes and microglia cells.
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27
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Hippocampal NR2B-containing NMDA receptors enhance long-term potentiation in rats with chronic visceral pain. Brain Res 2014; 1570:43-53. [DOI: 10.1016/j.brainres.2014.05.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 03/13/2014] [Accepted: 05/02/2014] [Indexed: 02/06/2023]
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