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Spekker E, Fejes-Szabó A, Nagy-Grócz G. Models of Trigeminal Activation: Is There an Animal Model of Migraine? Brain Sci 2024; 14:317. [PMID: 38671969 PMCID: PMC11048078 DOI: 10.3390/brainsci14040317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 03/20/2024] [Accepted: 03/25/2024] [Indexed: 04/28/2024] Open
Abstract
Migraine, recognized as a severe headache disorder, is widely prevalent, significantly impacting the quality of life for those affected. This article aims to provide a comprehensive review of the application of animal model technologies in unraveling the pathomechanism of migraine and developing more effective therapies. It introduces a variety of animal experimental models used in migraine research, emphasizing their versatility and importance in simulating various aspects of the condition. It details the benefits arising from the utilization of these models, emphasizing their role in elucidating pain mechanisms, clarifying trigeminal activation, as well as replicating migraine symptoms and histological changes. In addition, the article consciously acknowledges the inherent limitations and challenges associated with the application of animal experimental models. Recognizing these constraints is a fundamental step toward fine-tuning and optimizing the models for a more accurate reflection of and translatability to the human environment. Overall, a detailed and comprehensive understanding of migraine animal models is crucial for navigating the complexity of the disease. These findings not only provide a deeper insight into the multifaceted nature of migraine but also serve as a foundation for developing effective therapeutic strategies that specifically address the unique challenges arising from migraine pathology.
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Affiliation(s)
- Eleonóra Spekker
- Interdisciplinary Research Development and Innovation, Center of Excellence, University of Szeged, H-6725 Szeged, Hungary
| | - Annamária Fejes-Szabó
- HUN-REN–SZTE Neuroscience Research Group, University of Szeged, H-6725 Szeged, Hungary;
| | - Gábor Nagy-Grócz
- Department of Theoretical Health Sciences and Health Management, Faculty of Health Sciences and Social Studies, University of Szeged, Temesvári Krt. 31., H-6726 Szeged, Hungary;
- Preventive Health Sciences Research Group, Incubation Competence Centre of the Centre of Excellence for Interdisciplinary Research, Development and Innovation of the University of Szeged, H-6720 Szeged, Hungary
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2
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He W, Wang Y, Zhang Y, Zhang Y, Zhou J. The status of knowledge on migraines: The role of microglia. J Neuroimmunol 2023; 381:578118. [PMID: 37295033 DOI: 10.1016/j.jneuroim.2023.578118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/01/2023] [Accepted: 05/28/2023] [Indexed: 06/11/2023]
Abstract
Migraines are a considerable social problem and economic burden worldwide. Current acute treatments are based on inhibiting meningeal neurogenic inflammation which has poor results in some patients, whereas the site of action of prophylactic medicines are unknown; therefore, exploring new treatment mechanisms and methods is increasingly needed. Recent evidence suggests that microglia and microglia-mediated neuroinflammation are important in migraine pathogenesis. In the cortical spreading depression (CSD) migraine model, microglia were activated after multiple CSD stimulations, suggesting that microglial activation may be associated with recurrent attacks of migraine with aura. In the nitroglycerin-induced chronic migraine model, the microglial response to extracellular stimuli leads to the activation of surface purine receptors P2X4、P2X7、P2Y12, which mediate signal transduction through intracellular signalling cascades, such as the BDNF/TrkB, NLRP3/IL-1β and RhoA/ROCK signalling pathways, and release inflammatory mediators and cytokines that enhance pain by increasing the excitability of nearby neurons. Inhibition of the expression or function of these microglial receptors and pathways inhibits the abnormal excitability of TNC (trigeminal nucleus caudalis) neurons and intracranial as well as extracranial hyperalgesia in migraine animal models. These findings suggest that microglia may be central in migraine recurrent attacks and a potential target for the treatment of chronic headaches.
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Affiliation(s)
- Wei He
- Department of Neurology, The First Branch of The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yanyun Wang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yixin Zhang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yinan Zhang
- Department of Neurology, The First Branch of The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jiying Zhou
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
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Zhang S, Azubuine J, Schmeer C. A systematic literature review on the role of glial cells in the pathomechanisms of migraine. Front Mol Neurosci 2023; 16:1219574. [PMID: 37456527 PMCID: PMC10347403 DOI: 10.3389/fnmol.2023.1219574] [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: 05/09/2023] [Accepted: 06/13/2023] [Indexed: 07/18/2023] Open
Abstract
Background The pathomechanisms underlying migraine are intricate and remain largely unclear. Initially regarded as a neuronal disorder, migraine research primarily concentrated on understanding the pathophysiological changes within neurons. However, recent advances have revealed the significant involvement of neuroinflammation and the neuro-glio-vascular interplay in migraine pathogenesis. Methods A systematic search was conducted in PubMed, Scopus, and Web of Science databases from their inception until November 2022. The retrieved results underwent a screening process based on title and abstract, and the full texts of the remaining papers were thoroughly assessed for eligibility. Only studies that met the predetermined inclusion criteria were included in the review. Results Fifty-nine studies, consisting of 6 human studies and 53 animal studies, met the inclusion criteria. Among the 6 human studies, 2 focused on genetic analyses, while the remaining studies employed functional imaging, serum analyses and clinical trials. Regarding the 53 animal studies investigating glial cells in migraine, 19 of them explored the role of satellite glial cells and/or Schwann cells in the trigeminal ganglion and/or trigeminal nerve. Additionally, 17 studies highlighted the significance of microglia and/or astrocytes in the trigeminal nucleus caudalis, particularly in relation to central sensitization during migraine chronification. Furthermore, 17 studies examined the involvement of astrocytes and/or microglia in the cortex. Conclusion Glial cells, including astrocytes, microglia, satellite glial cells and Schwann cells in the central and peripheral nervous system, participate both in the development as well as chronic progression of migraine in disease-associated regions such as the trigeminovascular system, trigeminal nucleus caudalis and cortex, among other brain regions.
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Amani H, Soltani Khaboushan A, Terwindt GM, Tafakhori A. Glia Signaling and Brain Microenvironment in Migraine. Mol Neurobiol 2023; 60:3911-3934. [PMID: 36995514 DOI: 10.1007/s12035-023-03300-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 02/27/2023] [Indexed: 03/31/2023]
Abstract
Migraine is a complicated neurological disorder affecting 6% of men and 18% of women worldwide. Various mechanisms, including neuroinflammation, oxidative stress, altered mitochondrial function, neurotransmitter disturbances, cortical hyperexcitability, genetic factors, and endocrine system problems, are responsible for migraine. However, these mechanisms have not completely delineated the pathophysiology behind migraine, and they should be further studied. The brain microenvironment comprises neurons, glial cells, and vascular structures with complex interactions. Disruption of the brain microenvironment is the main culprit behind various neurological disorders. Neuron-glia crosstalk contributes to hyperalgesia in migraine. In the brain, microenvironment and related peripheral regulatory circuits, microglia, astrocytes, and satellite cells are necessary for proper function. These are the most important cells that could induce migraine headaches by disturbing the balance of the neurotransmitters in the nervous system. Neuroinflammation and oxidative stress are the prominent reactions glial cells drive during migraine. Understanding the role of cellular and molecular components of the brain microenvironment on the major neurotransmitters engaged in migraine pathophysiology facilitates the development of new therapeutic approaches with higher effectiveness for migraine headaches. Investigating the role of the brain microenvironment and neuroinflammation in migraine may help decipher its pathophysiology and provide an opportunity to develop novel therapeutic approaches for its management. This review aims to discuss the neuron-glia interactions in the brain microenvironment during migraine and their potential role as a therapeutic target for the treatment of migraine.
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Affiliation(s)
- Hanieh Amani
- Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Alireza Soltani Khaboushan
- Students' Scientific Research Center, Tehran University of Medical Sciences, Tehran, Iran.
- Iranian Center of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran.
| | - Gisela M Terwindt
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - Abbas Tafakhori
- Iranian Center of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran.
- Department of Neurology, Imam Khomeini Hospital, Keshavarz Blvd., Tehran, Iran.
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Zhou M, Pang F, Liao D, He X, Yang Y, Tang C. Electroacupuncture at Fengchi(GB20) and Yanglingquan(GB34) Ameliorates Paralgesia through Microglia-Mediated Neuroinflammation in a Rat Model of Migraine. Brain Sci 2023; 13:brainsci13040541. [PMID: 37190506 DOI: 10.3390/brainsci13040541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/17/2023] [Accepted: 03/22/2023] [Indexed: 03/29/2023] Open
Abstract
Background: Multiple studies have suggested that paralgesia (hyperalgesia and cutaneous allodynia) in migraine reflects the activation and sensitisation of the trigeminovascular system (TGVS). In particular, it reflects the second-order and higher nerve centre sensitisation, which is caused and maintained by neuroinflammation. Microglia activation leads to the release of proinflammatory cytokines involved in inflammatory responses. Accumulating evidence indicates that electroacupuncture (EA) is effective in ameliorating paralgesia, but the underlying mechanisms of EA in migraine attacks caused by microglia and microglia-mediated inflammatory responses are still unclear. The purpose of this study was to explore whether EA could ameliorate the dysregulation of pain sensation by suppressing microglial activation and the resulting neuroinflammatory response, and to evaluate whether this response was regulated by Toll-like receptor 4 (TLR4)/nuclear factor-kappa B(NF-κB) in the trigeminal nucleus caudalis (TNC) in a rat model of migraine. Methods: Repeated Inflammatory Soup (IS) was infused into the dura for seven sessions to establish a recurrent migraine-like rat model, and EA treatment was administered at Fengchi (GB20) and Yanglingquan (GB34) after daily IS infusion. Facial mechanical withdrawal thresholds were measured to evaluate the change in pain perception, and plasma samples and the TNC tissues of rats were collected to examine the changes in calcitonin gene-related peptide (CGRP), the Ibal-1-labelled microglial activation, and the resulting inflammatory response, including interleukin-1β (IL-1β), tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), and their regulatory molecules TLR4/NF-κB, via enzyme-linked immunosorbent assay (ELISA), real-time polymerase chain reaction (RT-PCR), immunohistochemistry (IHC) and Western blot analysis. Results: Repeated IS injections into the dura induced facial mechanical paralgesia, which is the manifestation of migraine attacks, and increased the expression of CGRP, Ibal-1, microglial mediated inflammatory cytokines (IL-1β, TNF-α, IL-6), and regulatory molecules TLR4/NF-κB. EA at GB20/34 significantly attenuated repetitive IS-induced pain hypersensitivity. This effect was consistent with decreased levels of CGRP and inflammatory cytokines in the plasma and the TNC via the inhibition of microglia activation, and this response may be regulated by TLR4/NF-κB. Conclusions: EA ameliorated paralgesia in repetitive IS-induced migraine-like rats, which was mainly mediated by a reduction in microglial activation and microglial-mediated inflammatory responses that could be regulated by TLR4/NF-κB.
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Kwilasz AJ, Clements MA, Larson TA, Harris KM, Litwiler ST, Woodall BJ, Todd LS, Schrama AEW, Mitten EH, Maier SF, Van Dam AM, Rice KC, Watkins LR. Involvement of TLR2-TLR4, NLRP3, and IL-17 in pain induced by a novel Sprague-Dawley rat model of experimental autoimmune encephalomyelitis. FRONTIERS IN PAIN RESEARCH 2022; 3:932530. [PMID: 36176709 PMCID: PMC9513159 DOI: 10.3389/fpain.2022.932530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 08/10/2022] [Indexed: 11/13/2022] Open
Abstract
Up to 92% of patients suffering from multiple sclerosis (MS) experience pain, most without adequate treatment, and many report pain long before motor symptoms associated with MS diagnosis. In the most commonly studied rodent model of MS, experimental autoimmune encephalomyelitis (EAE), motor impairments/disabilities caused by EAE can interfere with pain testing. In this study, we characterize a novel low-dose myelin-oligodendrocyte-glycoprotein (MOG)-induced Sprague-Dawley (SD) model of EAE-related pain in male rats, optimized to minimize motor impairments/disabilities. Adult male SD rats were treated with increasing doses of intradermal myelin-oligodendrocyte-glycoprotein (MOG1-125) (0, 4, 8, and 16 μg) in incomplete Freund's adjuvant (IFA) vehicle to induce mild EAE. Von Frey testing and motor assessments were conducted prior to EAE induction and then weekly thereafter to assess EAE-induced pain and motor impairment. Results from these studies demonstrated that doses of 8 and 16 μg MOG1-125 were sufficient to produce stable mechanical allodynia for up to 1 month in the absence of hindpaw motor impairments/disabilities. In the follow-up studies, these doses of MOG1-125, were administered to create allodynia in the absence of confounded motor impairments. Then, 2 weeks later, rats began daily subcutaneous injections of the Toll-like receptor 2 and 4 (TLR2-TLR4) antagonist (+)-naltrexone [(+)-NTX] or saline for an additional 13 days. We found that (+)-NTX also reverses EAE-induced mechanical allodynia in the MOG-induced SD rat model of EAE, supporting parallels between models, but now allowing a protracted timecourse to be examined completely free of motor confounds. Exploring further mechanisms, we demonstrated that both spinal NOD-like receptor protein 3 (NLRP3) and interleukin-17 (IL-17) are necessary for EAE-induced pain, as intrathecal injections of NLRP3 antagonist MCC950 and IL-17 neutralizing antibody both acutely reversed EAE-induced pain. Finally, we show that spinal glial immunoreactivity induced by EAE is reversed by (+)-NTX, and that spinal demyelination correlates with the severity of motor impairments/disabilities. These findings characterize an optimized MOG-induced SD rat model of EAE for the study of pain with minimal motor impairments/disabilities. Finally, these studies support the role of TLR2-TLR4 antagonists as a potential treatment for MS-related pain and other pain and inflammatory-related disorders.
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Affiliation(s)
- Andrew J. Kwilasz
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States
- The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Madison A. Clements
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States
- The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Tracey A. Larson
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States
- The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Kevin M. Harris
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States
- The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Scott T. Litwiler
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States
- The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Brodie J. Woodall
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States
- The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Laurel S. Todd
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States
- The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Anouk E. W. Schrama
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States
- The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Eric H. Mitten
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States
- The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Steven F. Maier
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States
- The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Anne-Marie Van Dam
- Department of Anatomy and Neuroscience, Amsterdam UMC, Vrije Universiteit, Amsterdam, Netherlands
| | - Kenner C. Rice
- Drug Design and Synthesis Section, National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, United States
| | - Linda R. Watkins
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States
- The Center for Neuroscience, University of Colorado, Boulder, CO, United States
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Liu X, Yang W, Zhu C, Sun S, Wu S, Wang L, Wang Y, Ge Z. Toll-like receptors and their role in neuropathic pain and migraine. Mol Brain 2022; 15:73. [PMID: 35987639 PMCID: PMC9392297 DOI: 10.1186/s13041-022-00960-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Accepted: 08/11/2022] [Indexed: 11/10/2022] Open
Abstract
Migraine is a complex neurological disease of unknown etiology involving both genetic and environmental factors. It has previously been reported that persistent pain may be mediated by the immune and inflammatory systems. Toll-like receptors (TLRs) play a significant role in immune and inflammatory responses and are expressed by microglia and astrocytes. One of the fundamental mechanisms of the innate immune system in coordinating inflammatory signal transduction is through TLRs, which protect the host organism by initiating inflammatory signaling cascades in response to tissue damage or stress. TLRs reside at the neuroimmune interface, and accumulating evidence has suggested that the inflammatory consequences of TLR activation on glia (mainly microglia and astrocytes), sensory neurons, and other cell types can influence nociceptive processing and lead to pain. Several studies have shown that TLRs may play a key role in neuropathic pain and migraine etiology by activating the microglia. The pathogenesis of migraine may involve a TLR-mediated crosstalk between neurons and immune cells. Innate responses in the central nervous system (CNS) occur during neuroinflammatory phenomena, including migraine. Antigens found in the environment play a crucial role in the inflammatory response, causing a broad range of diseases, including migraines. These can be recognized by several innate immune cells, including macrophages, microglia, and dendritic cells, and can be activated through TLR signaling. Given the prevalence of migraine and the insufficient efficacy and safety of current treatment options, a deeper understanding of TLRs is expected to provide novel therapies for managing chronic migraine. This review aimed to justify the view that TLRs may be involved in migraine.
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Pei P, Cui S, Zhang S, Hu S, Wang L, Yang W. Effect of Electroacupuncture at Fengchi on Facial Allodynia, Microglial Activation, and Microglia-Neuron Interaction in a Rat Model of Migraine. Brain Sci 2022; 12:brainsci12081100. [PMID: 36009163 PMCID: PMC9405615 DOI: 10.3390/brainsci12081100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 08/12/2022] [Accepted: 08/16/2022] [Indexed: 11/16/2022] Open
Abstract
The purpose of the work was to investigate whether electroacupuncture (EA) could ameliorate migraine central sensitization by modulating microglial activation and the subsequent release of inflammatory cytokines in the trigeminal nucleus caudalis (TNC) in a rat model. Establishment of a rat model of recurrent migraine was achieved through repeated dural electrical stimulation (DES). After nine sessions of acupuncture treatment at Fengchi (GB20), facial mechanical thresholds were measured by electronic von Frey measurements. Microglial activation and cytokine receptors of TNC were evaluated by immunofluorescence staining. The expression of microglial biological marker Ibal-1, proinflammatory cytokines, and cytokine receptors in the TNC were evaluated by Western blot and/or real-time polymerase chain reaction. In addition, the effects of inhibition of microglial activation on facial thresholds and neuronal activation (i.e., expression of c-Fos in the TNC) induced by DES were observed. After consecutive EA-GB20 treatments, the facial withdrawal threshold was significantly higher than in the model group at different time points (p < 0.05). The hyperreactivity of microglia induced by DES was significantly inhibited, and the expressions of Ibal-1, interleukin-1β, tumor necrosis factor-α, and their receptors in the TNC were also significantly decreased (p < 0.05). Inhibition of microglia by minocycline demonstrated an acupuncture-like role, which was manifested by ameliorated mechanical hyperalgesia and decreased neuronal expression of c-Fos, Iba-1, and inflammatory factors. EA at GB20 could ameliorate migraine facial allodynia by inhibiting microglial activation and the subsequent release of inflammatory cytokines and their receptors in the TNC.
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Affiliation(s)
- Pei Pei
- Neurology Department, The First Affiliated Hospital of Anhui University of Chinese Medicine, Hefei 230031, China
| | - Shengwei Cui
- Anhui University of Chinese Medicine, No. 350, Longzihu Road, Xinzhan District, Hefei 230012, China
| | - Shuaishuai Zhang
- Anhui University of Chinese Medicine, No. 350, Longzihu Road, Xinzhan District, Hefei 230012, China
| | - Sheng Hu
- Anhui University of Chinese Medicine, No. 350, Longzihu Road, Xinzhan District, Hefei 230012, China
| | - Linpeng Wang
- Acupuncture and Moxibustion Department, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing 100010, China
- Correspondence: (L.W.); (W.Y.)
| | - Wenming Yang
- Neurology Department, The First Affiliated Hospital of Anhui University of Chinese Medicine, Hefei 230031, China
- Correspondence: (L.W.); (W.Y.)
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9
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Reducha PV, Edvinsson L, Haanes KA. Could Experimental Inflammation Provide Better Understanding of Migraines? Cells 2022; 11:cells11152444. [PMID: 35954288 PMCID: PMC9368653 DOI: 10.3390/cells11152444] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 07/29/2022] [Accepted: 08/04/2022] [Indexed: 11/16/2022] Open
Abstract
Migraines constitute a common neurological and headache disorder affecting around 15% of the world’s population. In addition to other mechanisms, neurogenic neuroinflammation has been proposed to play a part in migraine chronification, which includes peripheral and central sensitization. There is therefore considerable evidence suggesting that inflammation in the intracranial meninges could be a key element in addition to calcitonin gene-related peptide (CGRP), leading to sensitization of trigeminal meningeal nociceptors in migraines. There are several studies that have utilized this approach, with a strong focus on using inflammatory animal models. Data from these studies show that the inflammatory process involves sensitization of trigeminovascular afferent nerve terminals. Further, by applying a wide range of different pharmacological interventions, insight has been gained on the pathways involved. Importantly, we discuss how animal models should be used with care and that it is important to evaluate outcomes in the light of migraine pathology.
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Affiliation(s)
- Philip Victor Reducha
- Department of Clinical Experimental Research, Glostrup Research Institute, Copenhagen University Hospital, Rigshospitalet Glostrup, 2600 Glostrup, Denmark
- Department of Biology, Section of Cell Biology and Physiology, University of Copenhagen, 1017 Copenhagen, Denmark
| | - Lars Edvinsson
- Department of Clinical Experimental Research, Glostrup Research Institute, Copenhagen University Hospital, Rigshospitalet Glostrup, 2600 Glostrup, Denmark
- Division of Experimental Vascular Research, Department of Clinical Sciences, Lund University Hospital, 221 00 Lund, Sweden
| | - Kristian Agmund Haanes
- Department of Clinical Experimental Research, Glostrup Research Institute, Copenhagen University Hospital, Rigshospitalet Glostrup, 2600 Glostrup, Denmark
- Department of Biology, Section of Cell Biology and Physiology, University of Copenhagen, 1017 Copenhagen, Denmark
- Correspondence:
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Guo Z, Zhang J, Liu X, Unsinger J, Hotchkiss RS, Cao YQ. Low-dose interleukin-2 reverses chronic migraine-related sensitizations through peripheral interleukin-10 and transforming growth factor beta-1 signaling. NEUROBIOLOGY OF PAIN 2022; 12:100096. [PMID: 35733705 PMCID: PMC9207571 DOI: 10.1016/j.ynpai.2022.100096] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/01/2022] [Accepted: 06/10/2022] [Indexed: 11/19/2022]
Abstract
Low-dose interleukin-2 treatment increases the levels of cytokine IL-10 and TGFβ1. Peripheral IL-10 and TGFβ1 signaling mediate the therapeutic effects of interleukin-2. IL-10 and TGFβ1 directly reverses chronic migraine-related peripheral sensitization.
Low-dose interleukin-2 (LD-IL-2) treatment has been shown to effectively reverse chronic migraine-related behaviors and the sensitization of trigeminal ganglion (TG) neurons through expansion and activation of peripheral regulatory T cells (Tregs) in mice. In this study, we investigated the molecular mechanisms underlying the effects of LD-IL-2 and Treg cells. LD-IL-2 treatment increases the production of cytokines interleukin-10 (IL-10) and transforming growth factor beta-1 (TGFβ1) in T cells, especially Treg cells, suggesting that they may mediate the therapeutic effect of LD-IL-2. Indeed, neutralizing antibodies against either IL-10 or TGFβ completely blocked the effects of LD-IL-2 on the facial mechanical hypersensitivity as well as the sensitization of TG neurons resulting from repeated nitroglycerin (NTG, a reliable trigger of migraine in patients) administration in mice, indicating that LD-IL-2 and Treg cells engage both peripheral IL-10 and TGFβ signaling pathways to reverse chronic-migraine related sensitizations. In an in vitro assay, incubation of TG culture with exogenous IL-10 or TGFβ1 fully reversed NTG-induced sensitization of TG neurons, suggesting that the IL-10 and TGFβ1 signaling in TG neurons contribute to LD-IL-2′s therapeutic effects. Collectively, these results not only elucidate the molecular mechanisms through which LD-IL-2 and Treg cells reverse chronic-migraine related sensitizations, but also suggest that the IL-10 and TGFβ1 signaling pathways in TG neurons are potential targets for chronic migraine therapy.
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Affiliation(s)
- Zhaohua Guo
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
- Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
| | - Jintao Zhang
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
- Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
| | - Xuemei Liu
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
- Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
| | - Jacqueline Unsinger
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Richard S Hotchkiss
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, United States
- Department of Surgery, Washington University School of Medicine, St. Louis, MO, United States
| | - Yu-Qing Cao
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
- Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
- Corresponding author at: Department of Anesthesiology and Pain Center, Washington University School of Medicine, 660 South Euclid, Campus Box MSC 8054-86-05, St. Louis, MO 63110, United States.
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Zhang L, Lu C, Kang L, Li Y, Tang W, Zhao D, Yu S, Liu R. Temporal characteristics of astrocytic activation in the TNC in a mice model of pain induced by recurrent dural infusion of inflammatory soup. J Headache Pain 2022; 23:8. [PMID: 35033010 PMCID: PMC8903672 DOI: 10.1186/s10194-021-01382-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 12/29/2021] [Indexed: 12/12/2022] Open
Abstract
Background Astrocytic activation might play a significant role in the central sensitization of chronic migraine (CM). However, the temporal characteristics of the astrocytic activation in the trigeminal nucleus caudalis (TNC) and the molecular mechanism under the process remain not fully understood. Therefore, this study aims to investigate the duration and levels change of astrocytic activation and to explore the correlation between astrocytic activation and the levels change of cytokines release. Methods We used a mice model induced by recurrent dural infusion of inflammatory soup (IS). The variation with time of IS-induced mechanical thresholds in the periorbital and hind paw plantar regions were evaluated using the von Frey filaments test. We detected the expression profile of glial fibrillary acidic protein (GFAP) in the TNC through immunofluorescence staining and western blot assay. We also investigated the variation with time of the transcriptional levels of GFAP and ionized calcium binding adapter molecule 1 (Iba1) through RNAscope in situ hybridization analysis. Then, we detected the variation with time of cytokines levels in the TNC tissue extraction and serum, including c-c motif chemokine ligand 2 (CCL2), c-c motif chemokine ligand 5 (CCL5), c-c motif chemokine ligand 7 (CCL7), c-c motif chemokine ligand 12 (CCL12), c-x-c motif chemokine ligand 1 (CXCL1), c-x-c motif chemokine ligand 13 (CXCL13), interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), macrophage colony-stimulating factor (M-CSF), interleukin 1beta (IL-1β), interleukin 6 (IL-6), interleukin 10 (IL-10), interleukin 17A (IL-17A). Results Recurrent IS infusion resulted in cutaneous allodynia in both the periorbital region and hind paw plantar, ranging from 5 d (after the second IS infusion) to 47 d (28 d after the last infusion) and 5 d to 26 d (7 d after the last infusion), respectively. The protein levels of GFAP and messenger ribonucleic acid (mRNA) levels of GFAP and Iba1 significantly increased and sustained from 20 d to 47 d (1 d to 28 d after the last infusion), which was associated with the temporal characteristics of astrocytic activation in the TNC. The CCL7 levels in the TNC decreased from 20 d to 47 d. But the CCL7 levels in serum only decreased on 20 d (1 d after the last infusion). The CCL12 levels in the TNC decreased on 22 d (3 d after the last infusion) and 33 d (14 d after the last infusion). In serum, the CCL12 levels only decreased on 22 d. The IL-10 levels in the TNC increased on 20 d. Conclusions Our results indicate that the astrocytic activation generated and sustained in the IS-induced mice model from 1 d to 28 d after the last infusion and may contribute to the pathology through modulating CCL7, CCL12, and IL-10 release.
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Affiliation(s)
- Leyi Zhang
- Medical School of Chinese PLA, Beijing, 100853, People's Republic of China.,Department of Neurology, the First Medical Center, Chinese PLA General Hospital, Fuxing Road 28, Haidian District, Beijing, 100853, People's Republic of China
| | - Chenglong Lu
- Medical School of Chinese PLA, Beijing, 100853, People's Republic of China.,Department of Neurology, the First Medical Center, Chinese PLA General Hospital, Fuxing Road 28, Haidian District, Beijing, 100853, People's Republic of China
| | - Li Kang
- Department of Neurology, the First Medical Center, Chinese PLA General Hospital, Fuxing Road 28, Haidian District, Beijing, 100853, People's Republic of China
| | - Yingji Li
- Department of Neurology, the First Medical Center, Chinese PLA General Hospital, Fuxing Road 28, Haidian District, Beijing, 100853, People's Republic of China
| | - Wenjing Tang
- Department of Neurology, the First Medical Center, Chinese PLA General Hospital, Fuxing Road 28, Haidian District, Beijing, 100853, People's Republic of China
| | - Dengfa Zhao
- Department of Neurology, the First Medical Center, Chinese PLA General Hospital, Fuxing Road 28, Haidian District, Beijing, 100853, People's Republic of China
| | - Shengyuan Yu
- Department of Neurology, the First Medical Center, Chinese PLA General Hospital, Fuxing Road 28, Haidian District, Beijing, 100853, People's Republic of China.
| | - Ruozhuo Liu
- Department of Neurology, the First Medical Center, Chinese PLA General Hospital, Fuxing Road 28, Haidian District, Beijing, 100853, People's Republic of China.
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12
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Spekker E, Tanaka M, Szabó Á, Vécsei L. Neurogenic Inflammation: The Participant in Migraine and Recent Advancements in Translational Research. Biomedicines 2021; 10:76. [PMID: 35052756 PMCID: PMC8773152 DOI: 10.3390/biomedicines10010076] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/23/2021] [Accepted: 12/27/2021] [Indexed: 12/24/2022] Open
Abstract
Migraine is a primary headache disorder characterized by a unilateral, throbbing, pulsing headache, which lasts for hours to days, and the pain can interfere with daily activities. It exhibits various symptoms, such as nausea, vomiting, sensitivity to light, sound, and odors, and physical activity consistently contributes to worsening pain. Despite the intensive research, little is still known about the pathomechanism of migraine. It is widely accepted that migraine involves activation and sensitization of the trigeminovascular system. It leads to the release of several pro-inflammatory neuropeptides and neurotransmitters and causes a cascade of inflammatory tissue responses, including vasodilation, plasma extravasation secondary to capillary leakage, edema, and mast cell degranulation. Convincing evidence obtained in rodent models suggests that neurogenic inflammation is assumed to contribute to the development of a migraine attack. Chemical stimulation of the dura mater triggers activation and sensitization of the trigeminal system and causes numerous molecular and behavioral changes; therefore, this is a relevant animal model of acute migraine. This narrative review discusses the emerging evidence supporting the involvement of neurogenic inflammation and neuropeptides in the pathophysiology of migraine, presenting the most recent advances in preclinical research and the novel therapeutic approaches to the disease.
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Affiliation(s)
- Eleonóra Spekker
- Neuroscience Research Group, Hungarian Academy of Sciences, University of Szeged (MTA-SZTE), H-6725 Szeged, Hungary; (E.S.); (M.T.)
| | - Masaru Tanaka
- Neuroscience Research Group, Hungarian Academy of Sciences, University of Szeged (MTA-SZTE), H-6725 Szeged, Hungary; (E.S.); (M.T.)
- Interdisciplinary Excellence Centre, Department of Neurology, Albert Szent-Györgyi Medical School, University of Szeged, H-6725 Szeged, Hungary;
| | - Ágnes Szabó
- Interdisciplinary Excellence Centre, Department of Neurology, Albert Szent-Györgyi Medical School, University of Szeged, H-6725 Szeged, Hungary;
| | - László Vécsei
- Neuroscience Research Group, Hungarian Academy of Sciences, University of Szeged (MTA-SZTE), H-6725 Szeged, Hungary; (E.S.); (M.T.)
- Interdisciplinary Excellence Centre, Department of Neurology, Albert Szent-Györgyi Medical School, University of Szeged, H-6725 Szeged, Hungary;
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13
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Li X, Zou Y, Fu YY, Xing J, Wang KY, Wan PZ, Wang M, Zhai XY. Ibudilast Attenuates Folic Acid-Induced Acute Kidney Injury by Blocking Pyroptosis Through TLR4-Mediated NF-κB and MAPK Signaling Pathways. Front Pharmacol 2021; 12:650283. [PMID: 34025417 PMCID: PMC8139578 DOI: 10.3389/fphar.2021.650283] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 04/19/2021] [Indexed: 02/06/2023] Open
Abstract
Folic acid (FA)-induced renal tubule damage, which is characterized by extensive inflammation, is a common model of acute kidney injury (AKI). Pyroptosis, a pro-inflammatory form of cell death due to the activation of inflammatory caspases, is involved in AKI progression. Ibudilast, a TLR4 antagonist, has been used in the clinic to exert an anti-inflammatory effect on asthma. However, researchers have not explored whether ibudilast exerts a protective effect on AKI by inhibiting inflammation. In the present study, ibudilast reversed FA-induced AKI in mice, as indicated by the reduced serum creatinine and urea nitrogen levels, and improved renal pathology, as well as the downregulation of kidney injury marker-1. In addition, ibudilast significantly increased the production of the anti-inflammatory factor IL-10 while suppressing the secretion of the pro-inflammatory cytokine TNF-α and macrophage infiltration. Moreover, in the injured kidney, ibudilast reduced the levels of both inflammasome markers (NLRP3) and pyroptosis-related proteins (caspase-1, IL1-β, IL-18, and GSDMD cleavage), and decreased the number of TUNEL-positive cells. Further mechanistic studies showed that ibudilast administration inhibited the FA-induced upregulation of TLR4, blocked NF-κB nuclear translocation, and reduced the phosphorylation of NF-κB and IκBα, p38, ERK, and JNK. Thus, this study substantiates the protective effect of ibudilast on FA-induced AKI in mice and suggests that protection might be achieved by reducing pyroptosis and inflammation, likely through the inhibition of TLR4-mediated NF-κB and MAPK signaling pathways.
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Affiliation(s)
- Xue Li
- Department of Histology and Embryology, Basic Medical College, China Medical University, Shenyang, China.,Department of Nephrology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Yu Zou
- Department of Histology and Embryology, Basic Medical College, China Medical University, Shenyang, China
| | - Yuan-Yuan Fu
- Department of Histology and Embryology, Basic Medical College, China Medical University, Shenyang, China
| | - Jia Xing
- Department of Histology and Embryology, Basic Medical College, China Medical University, Shenyang, China
| | - Kai-Yue Wang
- Department of Histology and Embryology, Basic Medical College, China Medical University, Shenyang, China
| | - Peng-Zhi Wan
- Department of Nephrology, First Affiliated Hospital of China Medical University, Shenyang, China
| | - Mo Wang
- Department of Surgery, Yale School of Medicine, New Haven, CT, United States
| | - Xiao-Yue Zhai
- Department of Histology and Embryology, Basic Medical College, China Medical University, Shenyang, China.,Institute of Nephropathology, China Medical University, Shenyang, China
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14
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Magni G, Ceruti S. Purines in Pain as a Gliopathy. Front Pharmacol 2021; 12:649807. [PMID: 33790798 PMCID: PMC8006436 DOI: 10.3389/fphar.2021.649807] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 01/29/2021] [Indexed: 12/30/2022] Open
Affiliation(s)
- Giulia Magni
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Stefania Ceruti
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
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15
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Kwilasz AJ, Green Fulgham SM, Duran-Malle JC, Schrama AEW, Mitten EH, Todd LS, Patel HP, Larson TA, Clements MA, Harris KM, Litwiler ST, Harvey LO, Maier SF, Chavez RA, Rice KC, Van Dam AM, Watkins LR. Toll-like receptor 2 and 4 antagonism for the treatment of experimental autoimmune encephalomyelitis (EAE)-related pain. Brain Behav Immun 2021; 93:80-95. [PMID: 33358978 PMCID: PMC8475740 DOI: 10.1016/j.bbi.2020.12.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 12/07/2020] [Accepted: 12/16/2020] [Indexed: 12/26/2022] Open
Abstract
Neuropathic pain is a major symptom of multiple sclerosis (MS) with up to 92% of patients reporting bodily pain, and 85% reporting pain severe enough to cause functional disability. None of the available therapeutics target MS pain. Toll-like receptors 2 and 4 (TLR2/TLR4) have emerged as targets for treating a wide array of autoimmune disorders, including MS, as well as having demonstrated success at suppressing pain in diverse animal models. The current series of studies tested systemic TLR2/TLR4 antagonists in males and females in a low-dose Myelin oligodendrocyte glycoprotein (MOG) experimental autoimmune encephalomyelitis (EAE) model, with reduced motor dysfunction to allow unconfounded testing of allodynia through 50+ days post-MOG. The data demonstrated that blocking TLR2/TLR4 suppressed EAE-related pain, equally in males and females; upregulation of dorsal spinal cord proinflammatory gene expression for TLR2, TLR4, NLRP3, interleukin-1β, IkBα, TNF-α and interleukin-17; and upregulation of dorsal spinal cord expression of glial immunoreactivity markers. In support of these results, intrathecal interleukin-1 receptor antagonist reversed EAE-induced allodynia, both early and late after EAE induction. In contrast, blocking TLR2/TLR4 did not suppress EAE-induced motor disturbances induced by a higher MOG dose. These data suggest that blocking TLR2/TLR4 prevents the production of proinflammatory factors involved in low dose EAE pathology. Moreover, in this EAE model, TLR2/TLR4 antagonists were highly effective in reducing pain, whereas motor impairment, as seen in high dose MOG EAE, is not affected.
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Affiliation(s)
- Andrew J Kwilasz
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States.
| | - Suzanne M Green Fulgham
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Julissa Chante Duran-Malle
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Anouk E W Schrama
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Eric H Mitten
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Laurel S Todd
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Hardik P Patel
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Tracey A Larson
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Madison A Clements
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Kevin M Harris
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Scott T Litwiler
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Lewis O Harvey
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | - Steven F Maier
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
| | | | - Kenner C Rice
- Drug Design and Synthesis Section, National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, United States
| | - Anne-Marie Van Dam
- Department of Anatomy and Neuroscience, Amsterdam UMC, Vrije Universiteit, Amsterdam, Netherlands
| | - Linda R Watkins
- Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, United States; The Center for Neuroscience, University of Colorado, Boulder, CO, United States
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17
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Frederiksen SD, Warfvinge K, Ohlsson L, Edvinsson L. Expression of Pituitary Adenylate Cyclase-activating Peptide, Calcitonin Gene-related Peptide and Headache Targets in the Trigeminal Ganglia of Rats and Humans. Neuroscience 2018; 393:319-332. [DOI: 10.1016/j.neuroscience.2018.10.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 09/28/2018] [Accepted: 10/02/2018] [Indexed: 11/16/2022]
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18
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Bruno K, Woller SA, Miller YI, Yaksh TL, Wallace M, Beaton G, Chakravarthy K. Targeting toll-like receptor-4 (TLR4)-an emerging therapeutic target for persistent pain states. Pain 2018; 159:1908-1915. [PMID: 29889119 PMCID: PMC7890571 DOI: 10.1097/j.pain.0000000000001306] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Toll-like receptors (TLRs) are a family of pattern recognition receptors that initiate signaling in innate and adaptive immune pathways. The highly conserved family of transmembrane proteins comprises an extracellular domain that recognizes exogenous and endogenous danger molecules and an ectodomain that activates downstream pathways in response. Recent studies suggest that continuous activation or dysregulation of TLR signaling may contribute to chronic disease states. The receptor is located not only on inflammatory cells (meningeal and peripheral macrophages) but on neuraxial glia (microglia and astrocytes), Schwann cells, fibroblasts, dorsal root ganglia, and dorsal horn neurons. Procedures blocking TLR functionality have shown pronounced effects on pain behavior otherwise observed in models of chronic inflammation and nerve injury. This review addresses the role of TLR4 as an emerging therapeutic target for the evolution of persistent pain and its role in noncanonical signaling, mediating anomalous pro-algesic actions of opiates. Accordingly, molecules targeting inhibition of this receptor have promise as disease-modifying and opioid-sparing alternatives for persistent pain states.
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Affiliation(s)
- Kelly Bruno
- Department of Anesthesiology and Pain Medicine, University of California San Diego Health Sciences, La Jolla, CA, USA
- VA San Diego Healthcare System, San Diego, CA, USA
- Center for Excellence in Stress and Mental Health, VA San Diego Healthcare System, San Diego, CA, USA
| | - Sarah A. Woller
- Department of Anesthesiology and Pain Medicine, University of California San Diego Health Sciences, La Jolla, CA, USA
| | - Yury I. Miller
- Department of Medicine, University of California San Diego Health Science, La Jolla, CA, USA
| | - Tony L. Yaksh
- Department of Anesthesiology and Pain Medicine, University of California San Diego Health Sciences, La Jolla, CA, USA
- Douleur Therapeutics, 10225 Barnes Canyon Road, Suite A104, San Diego, CA, USA
| | - Mark Wallace
- Department of Anesthesiology and Pain Medicine, University of California San Diego Health Sciences, La Jolla, CA, USA
- Douleur Therapeutics, 10225 Barnes Canyon Road, Suite A104, San Diego, CA, USA
| | - Graham Beaton
- Douleur Therapeutics, 10225 Barnes Canyon Road, Suite A104, San Diego, CA, USA
| | - Krishnan Chakravarthy
- Department of Anesthesiology and Pain Medicine, University of California San Diego Health Sciences, La Jolla, CA, USA
- VA San Diego Healthcare System, San Diego, CA, USA
- Douleur Therapeutics, 10225 Barnes Canyon Road, Suite A104, San Diego, CA, USA
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