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Wijesinghe SN, Ditchfield C, Flynn S, Agrawal J, Davis ET, Dajas-Bailador F, Chapman V, Jones SW. Immunomodulation and fibroblast dynamics driving nociceptive joint pain within inflammatory synovium: Unravelling mechanisms for therapeutic advancements in osteoarthritis. Osteoarthritis Cartilage 2024:S1063-4584(24)01267-6. [PMID: 38960140 DOI: 10.1016/j.joca.2024.06.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 05/21/2024] [Accepted: 06/25/2024] [Indexed: 07/05/2024]
Abstract
OBJECTIVE Synovitis is a widely accepted sign of osteoarthritis (OA), characterised by tissue hyperplasia, where increased infiltration of immune cells and proliferation of resident fibroblasts adopt a pro-inflammatory phenotype, and increased the production of pro-inflammatory mediators that are capable of sensitising and activating sensory nociceptors, which innervate the joint tissues. As such, it is important to understand the cellular composition of synovium and their involvement in pain sensitisation to better inform the development of effective analgesics. METHODS Studies investigating pain sensitisation in OA with a focus on immune cells and fibroblasts were identified using PubMed, Web of Science and SCOPUS. RESULTS In this review, we comprehensively assess the evidence that cellular crosstalk between resident immune cells or synovial fibroblasts with joint nociceptors in inflamed OA synovium contributes to peripheral pain sensitisation. Moreover, we explore whether the elucidation of common mechanisms identified in similar joint conditions may inform the development of more effective analgesics specifically targeting OA joint pain. CONCLUSION The concept of local environment and cellular crosstalk within the inflammatory synovium as a driver of nociceptive joint pain presents a compelling opportunity for future research and therapeutic advancements.
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Affiliation(s)
- Susanne N Wijesinghe
- Institute of Inflammation and Ageing, MRC-ARUK Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham B15 2TT, UK.
| | - Caitlin Ditchfield
- Institute of Inflammation and Ageing, MRC-ARUK Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham B15 2TT, UK.
| | - Sariah Flynn
- Institute of Inflammation and Ageing, MRC-ARUK Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham B15 2TT, UK.
| | - Jyoti Agrawal
- School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK.
| | | | | | - Victoria Chapman
- Pain Centre Versus Arthritis, NIHR Nottingham Biomedical Research Centre, University of Nottingham, Nottingham NG7 2UH, UK.
| | - Simon W Jones
- Institute of Inflammation and Ageing, MRC-ARUK Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham B15 2TT, UK.
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David ET, Yousuf MS, Mei HR, Jain A, Krishnagiri S, Elahi H, Venkatesan R, Srikanth KD, Dussor G, Dalva MB, Price TJ. ephrin-B2 promotes nociceptive plasticity and hyperalgesic priming through EphB2-MNK-eIF4E signaling in both mice and humans. Pharmacol Res 2024; 206:107284. [PMID: 38925462 DOI: 10.1016/j.phrs.2024.107284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2024] [Revised: 06/21/2024] [Accepted: 06/22/2024] [Indexed: 06/28/2024]
Abstract
Ephrin-B-EphB signaling can promote pain through ligand-receptor interactions between peripheral cells, like immune cells expressing ephrin-Bs, and EphB receptors expressed by DRG neurons. Previous studies have shown increased ephrin-B2 expression in peripheral tissues like synovium of rheumatoid and osteoarthritis patients, indicating the clinical significance of this signaling. The primary goal of this study was to understand how ephrin-B2 acts on mouse and human DRG neurons, which express EphB receptors, to promote pain and nociceptor plasticity. We hypothesized that ephrin-B2 would promote nociceptor plasticity and hyperalgesic priming through MNK-eIF4E signaling, a critical mechanism for nociceptive plasticity induced by growth factors, cytokines and nerve injury. Both male and female mice developed dose-dependent mechanical hypersensitivity in response to ephrin-B2, and both sexes showed hyperalgesic priming when challenged with PGE2 injection either to the paw or the cranial dura. Acute nociceptive behaviors and hyperalgesic priming were blocked in mice lacking MNK1 (Mknk1 knockout mice) and by eFT508, a specific MNK inhibitor. Sensory neuron-specific knockout of EphB2 using Pirt-Cre demonstrated that ephrin-B2 actions require this receptor. In Ca2+-imaging experiments on cultured DRG neurons, ephrin-B2 treatment enhanced Ca2+ transients in response to PGE2 and these effects were absent in DRG neurons from MNK1-/- and EphB2-PirtCre mice. In experiments on human DRG neurons, ephrin-B2 increased eIF4E phosphorylation and enhanced Ca2+ responses to PGE2 treatment, both blocked by eFT508. We conclude that ephrin-B2 acts directly on mouse and human sensory neurons to induce nociceptor plasticity via MNK-eIF4E signaling, offering new insight into how ephrin-B signaling promotes pain.
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Affiliation(s)
- Eric T David
- University of Texas at Dallas, School of Behavioral and Brain Sciences, Department of Neuroscience, Center for Advanced Pain Studies
| | - Muhammad Saad Yousuf
- University of Texas at Dallas, School of Behavioral and Brain Sciences, Department of Neuroscience, Center for Advanced Pain Studies
| | - Hao-Ruei Mei
- University of Texas at Dallas, School of Behavioral and Brain Sciences, Department of Neuroscience, Center for Advanced Pain Studies
| | - Ashita Jain
- University of Texas at Dallas, School of Behavioral and Brain Sciences, Department of Neuroscience, Center for Advanced Pain Studies
| | - Sharada Krishnagiri
- University of Texas at Dallas, School of Behavioral and Brain Sciences, Department of Neuroscience, Center for Advanced Pain Studies
| | - Hajira Elahi
- University of Texas at Dallas, School of Behavioral and Brain Sciences, Department of Neuroscience, Center for Advanced Pain Studies
| | - Rupali Venkatesan
- University of Texas at Dallas, School of Behavioral and Brain Sciences, Department of Neuroscience, Center for Advanced Pain Studies
| | - Kolluru D Srikanth
- Jefferson Synaptic Biology Center, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107; Tulane Brain Institute, Department of Cell and Molecular Biology, Tulane University; New Orleans, LA 70124, USA
| | - Gregory Dussor
- University of Texas at Dallas, School of Behavioral and Brain Sciences, Department of Neuroscience, Center for Advanced Pain Studies
| | - Matthew B Dalva
- Jefferson Synaptic Biology Center, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107; Tulane Brain Institute, Department of Cell and Molecular Biology, Tulane University; New Orleans, LA 70124, USA
| | - Theodore J Price
- University of Texas at Dallas, School of Behavioral and Brain Sciences, Department of Neuroscience, Center for Advanced Pain Studies.
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3
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Einhorn LM, Krishnan P, Poirier C, Ingelmo P. Chronic Postsurgical Pain in Children and Adolescents: A Call for Action. J Pain Res 2024; 17:1967-1978. [PMID: 38828088 PMCID: PMC11144433 DOI: 10.2147/jpr.s464009] [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: 02/18/2024] [Accepted: 05/17/2024] [Indexed: 06/05/2024] Open
Abstract
Chronic postsurgical pain (CPSP) affects a significant proportion of children and adolescents after major surgery and is a detriment to both short- and long-term recovery outcomes. While clinical characteristics and psychosocial risk factors for developing CPSP in children and adults are well established in the literature, there has been little progress on the prevention and management of CPSP after pediatric surgery. Limited evidence to support current pharmacologic approaches suggests a fundamentally new paradigm must be considered by clinicians to both conceptualize and address this adverse complication. This narrative review provides a comprehensive evaluation of both the known and emerging mechanisms that support our current understanding of CPSP. Additionally, we discuss the importance of optimizing perioperative analgesic strategies to mitigate CPSP based on individual patient risks. We highlight the importance of postoperative pain trajectories to identify those most at risk for developing CPSP, the early referral to multi-disciplinary pain clinics for comprehensive evaluation and treatment of CPSP, and additional work needed to differentiate CPSP characteristics from other chronic pain syndromes in children. Finally, we recognize ongoing challenges associated with the universal implementation of available knowledge about pediatric CPSP into practically useful care plans for clinicians.
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Affiliation(s)
- Lisa M Einhorn
- Department of Anesthesiology, Division of Pediatrics, Duke University School of Medicine, Durham, NC, USA
| | - Padmaja Krishnan
- Campbell University School of Osteopathic Medicine, Lillington, NC, USA
| | - Cassandra Poirier
- Department of Anesthesiology, University of British Columbia, Kelowna, BC, Canada
| | - Pablo Ingelmo
- Edwards Family Interdisciplinary Center for Complex Pain, Montreal Children’s Hospital, McGill University Health Center, Montreal, QC, Canada
- Research Institute, McGill University Health Center, Montreal, QC, Canada
- Department of Anesthesia, McGill University, Montreal, QC, Canada
- Alan Edwards Center for Research in Pain, Montreal, QC, Canada
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4
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Fotio Y, Mabou Tagne A, Squire E, Lee HL, Phillips CM, Chang K, Ahmed F, Greenberg AS, Villalta SA, Scarfone VM, Spadoni G, Mor M, Piomelli D. NAAA-regulated lipid signaling in monocytes controls the induction of hyperalgesic priming in mice. Nat Commun 2024; 15:1705. [PMID: 38402219 PMCID: PMC10894261 DOI: 10.1038/s41467-024-46139-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 02/15/2024] [Indexed: 02/26/2024] Open
Abstract
Circulating monocytes participate in pain chronification but the molecular events that cause their deployment are unclear. Using a mouse model of hyperalgesic priming (HP), we show that monocytes enable progression to pain chronicity through a mechanism that requires transient activation of the hydrolase, N-acylethanolamine acid amidase (NAAA), and the consequent suppression of NAAA-regulated lipid signaling at peroxisome proliferator-activated receptor-α (PPAR-α). Inhibiting NAAA in the 72 hours following administration of a priming stimulus prevented HP. This effect was phenocopied by NAAA deletion and depended on PPAR-α recruitment. Mice lacking NAAA in CD11b+ cells - monocytes, macrophages, and neutrophils - were resistant to HP induction. Conversely, mice overexpressing NAAA or lacking PPAR-α in the same cells were constitutively primed. Depletion of monocytes, but not resident macrophages, generated mice that were refractory to HP. The results identify NAAA-regulated signaling in monocytes as a control node in the induction of HP and, potentially, the transition to pain chronicity.
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Affiliation(s)
- Yannick Fotio
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | - Alex Mabou Tagne
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | - Erica Squire
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | - Hye-Lim Lee
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | - Connor M Phillips
- Department of Physiology and Biophysics, University of California Irvine, Irvine, CA, USA
| | - Kayla Chang
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | - Faizy Ahmed
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | | | - S Armando Villalta
- Department of Physiology and Biophysics, University of California Irvine, Irvine, CA, USA
- Department of Neurology, University of California Irvine, Irvine, CA, USA
| | - Vanessa M Scarfone
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA, USA
| | - Gilberto Spadoni
- Dipartimento di Scienze Biomolecolari, Università di Urbino "Carlo Bo,", Urbino, Italy
| | - Marco Mor
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università di Parma, Parma, Italy
| | - Daniele Piomelli
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA.
- Department of Biological Chemistry, University of California Irvine, Irvine, CA, USA.
- Department of Pharmaceutical Sciences, University of California Irvine, Irvine, CA, USA.
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5
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Echeverria-Villalobos M, Tortorici V, Brito BE, Ryskamp D, Uribe A, Weaver T. The role of neuroinflammation in the transition of acute to chronic pain and the opioid-induced hyperalgesia and tolerance. Front Pharmacol 2023; 14:1297931. [PMID: 38161698 PMCID: PMC10755684 DOI: 10.3389/fphar.2023.1297931] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 12/04/2023] [Indexed: 01/03/2024] Open
Abstract
Current evidence suggests that activation of glial and immune cells leads to increased production of proinflammatory mediators, creating a neuroinflammatory state. Neuroinflammation has been proven to be a fundamental mechanism in the genesis of acute pain and its transition to neuropathic and chronic pain. A noxious event that stimulates peripheral afferent nerve fibers may also activate pronociceptive receptors situated at the dorsal root ganglion and dorsal horn of the spinal cord, as well as peripheral glial cells, setting off the so-called peripheral sensitization and spreading neuroinflammation to the brain. Once activated, microglia produce cytokines, chemokines, and neuropeptides that can increase the sensitivity and firing properties of second-order neurons, upregulating the signaling of nociceptive information to the cerebral cortex. This process, known as central sensitization, is crucial for chronification of acute pain. Immune-neuronal interactions are also implicated in the lesser-known complex regulatory relationship between pain and opioids. Current evidence suggests that activated immune and glial cells can alter neuronal function, induce, and maintain pathological pain, and disrupt the analgesic effects of opioid drugs by contributing to the development of tolerance and dependence, even causing paradoxical hyperalgesia. Such alterations may occur when the neuronal environment is impacted by trauma, inflammation, and immune-derived molecules, or when opioids induce proinflammatory glial activation. Hence, understanding these intricate interactions may help in managing pain signaling and opioid efficacy beyond the classical pharmacological approach.
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Affiliation(s)
| | - Victor Tortorici
- Neuroscience Laboratory, Faculty of Science, Department of Behavioral Sciences, Universidad Metropolitana, Caracas, Venezuela
- Neurophysiology Laboratory, Center of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Beatriz E. Brito
- Immunopathology Laboratory, Center of Experimental Medicine, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - David Ryskamp
- College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Alberto Uribe
- Anesthesiology Department, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Tristan Weaver
- Anesthesiology Department, The Ohio State University Wexner Medical Center, Columbus, OH, United States
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6
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Pereira AFM, Cavalcante JS, Angstmam DG, Almeida C, Soares GS, Pucca MB, Ferreira Junior RS. Unveiling the Pain Relief Potential: Harnessing Analgesic Peptides from Animal Venoms. Pharmaceutics 2023; 15:2766. [PMID: 38140106 PMCID: PMC10748172 DOI: 10.3390/pharmaceutics15122766] [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: 09/19/2023] [Revised: 11/08/2023] [Accepted: 12/05/2023] [Indexed: 12/24/2023] Open
Abstract
The concept of pain encompasses a complex interplay of sensory and emotional experiences associated with actual or potential tissue damage. Accurately describing and localizing pain, whether acute or chronic, mild or severe, poses a challenge due to its diverse manifestations. Understanding the underlying origins and mechanisms of these pain variations is crucial for effective management and pharmacological interventions. Derived from a wide spectrum of species, including snakes, arthropods, mollusks, and vertebrates, animal venoms have emerged as abundant repositories of potential biomolecules exhibiting analgesic properties across a broad spectrum of pain models. This review focuses on highlighting the most promising venom-derived toxins investigated as potential prototypes for analgesic drugs. The discussion further encompasses research prospects, challenges in advancing analgesics, and the practical application of venom-derived toxins. As the field continues its evolution, tapping into the latent potential of these natural bioactive compounds holds the key to pioneering approaches in pain management and treatment. Therefore, animal toxins present countless possibilities for treating pain caused by different diseases. The development of new analgesic drugs from toxins is one of the directions that therapy must follow, and it seems to be moving forward by recommending the composition of multimodal therapy to combat pain.
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Affiliation(s)
- Ana Flávia Marques Pereira
- Center for the Study of Venoms and Venomous Animals (CEVAP), São Paulo State University (UNESP—Univ Estadual Paulista), Botucatu 01419-901, SP, Brazil;
| | - Joeliton S. Cavalcante
- Graduate Program in Tropical Diseases, Botucatu Medical School (FMB), São Paulo State University (UNESP—Univ Estadual Paulista), Botucatu 01419-901, SP, Brazil; (J.S.C.); (D.G.A.)
| | - Davi Gomes Angstmam
- Graduate Program in Tropical Diseases, Botucatu Medical School (FMB), São Paulo State University (UNESP—Univ Estadual Paulista), Botucatu 01419-901, SP, Brazil; (J.S.C.); (D.G.A.)
| | - Cayo Almeida
- Center of Mathematics, Computing Sciences and Cognition, Federal University of ABC, Santo André 09280-560, SP, Brazil;
| | - Gean S. Soares
- Delphina Rinaldi Abdel Azil Hospital and Emergency Room (HPSDRAA), Manaus 69093-415, AM, Brazil;
| | - Manuela B. Pucca
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University, Araraquara 14801-320, SP, Brazil;
| | - Rui Seabra Ferreira Junior
- Center for the Study of Venoms and Venomous Animals (CEVAP), São Paulo State University (UNESP—Univ Estadual Paulista), Botucatu 01419-901, SP, Brazil;
- Graduate Program in Tropical Diseases, Botucatu Medical School (FMB), São Paulo State University (UNESP—Univ Estadual Paulista), Botucatu 01419-901, SP, Brazil; (J.S.C.); (D.G.A.)
- Center for Translational Science and Development of Biopharmaceuticals FAPESP/CEVAP, São Paulo State University (UNESP—Univ Estadual Paulista), Botucatu 01419-901, SP, Brazil
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7
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Marini D, Monk JE, Campbell DL, Lee C, Belson S, Small A. Sex impacts pain behaviour but not emotional reactivity of lambs following ring tail docking. PeerJ 2023; 11:e15092. [PMID: 37009150 PMCID: PMC10064992 DOI: 10.7717/peerj.15092] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 02/27/2023] [Indexed: 03/30/2023] Open
Abstract
Studies in humans have shown sex differences in response to painful events, however, little is known in relation to sex differences in sheep. Understanding sex differences would enable improved experimental design and interpretation of studies of painful procedures in sheep. To examine sex differences in response to pain, 80 lambs were tested across five cohorts of 16. The lambs were penned in groups containing two male and two female lambs with their respective mothers. Lambs were randomly allocated from within each block to one of four treatment groups; FRing–Female lamb, ring tail docked without analgesia, MRing–Male lamb, ring tail docked without analgesia, FSham–Female lamb, tail manipulated and MSham–Male lamb, tail manipulated. Following treatment, lambs were returned to their pen and were video recorded for 45 mins for behavioural observations of acute pain and posture. An hour after treatment, lambs then underwent an emotional reactivity test that consisted of three phases: Isolation, Novelty and Startle. Following treatment, Ring lambs displayed more abnormal postures (mean = 2.5 ± 0.5) compared to Sham lambs (mean = 0.05 ± 0.4, P = 0.0001). There was an effect of sex on the display of acute pain-related behaviours in lambs that were tail docked (P < 0.001), with female lambs displaying more acute behaviours (mean count = +2.2). This difference in behaviour between sexes was not observed in Sham lambs. There was no effect of sex on display of postures related to pain (P = 0.99). During the Novelty and Startle phase of the emotional reactivity test, Ring lambs tended to (P = 0.084) or did (P = 0.018) show more fear related behaviours, respectively. However, no effect of sex was observed. The results of this study indicate that a pain state may alter the emotional response of lambs to novel objects and potential fearful situations. It was also demonstrated that female lambs display increased sensitivity to the acute pain caused by tail docking compared to males.
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Affiliation(s)
- Danila Marini
- Agriculture and Food, The Commonwealth Scientific and Industrial Research Organisation, Armidale, New South Wales, Australia
- Davies Livestock Research Centre, School of Animal and Veterinary Science, The University of Adelaide, Adelaide, South Australia, Australia
| | - Jessica E. Monk
- Agriculture and Food, The Commonwealth Scientific and Industrial Research Organisation, Armidale, New South Wales, Australia
- School of Environmental and Rural Science, The University of New England, Armidale, New South Wales, Australia
| | - Dana L.M. Campbell
- Agriculture and Food, The Commonwealth Scientific and Industrial Research Organisation, Armidale, New South Wales, Australia
| | - Caroline Lee
- Agriculture and Food, The Commonwealth Scientific and Industrial Research Organisation, Armidale, New South Wales, Australia
| | - Sue Belson
- Agriculture and Food, The Commonwealth Scientific and Industrial Research Organisation, Armidale, New South Wales, Australia
| | - Alison Small
- Agriculture and Food, The Commonwealth Scientific and Industrial Research Organisation, Armidale, New South Wales, Australia
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8
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Büchel C. The role of expectations, control and reward in the development of pain persistence based on a unified model. eLife 2023; 12:81795. [PMID: 36972108 PMCID: PMC10042542 DOI: 10.7554/elife.81795] [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: 07/12/2022] [Accepted: 03/20/2023] [Indexed: 03/29/2023] Open
Abstract
Chronic, or persistent pain affects more than 10% of adults in the general population. This makes it one of the major physical and mental health care problems. Although pain is an important acute warning signal that allows the organism to take action before tissue damage occurs, it can become persistent and its role as a warning signal thereby inadequate. Although per definition, pain can only be labeled as persistent after 3 months, the trajectory from acute to persistent pain is likely to be determined very early and might even start at the time of injury. The biopsychosocial model has revolutionized our understanding of chronic pain and paved the way for psychological treatments for persistent pain, which routinely outperform other forms of treatment. This suggests that psychological processes could also be important in shaping the very early trajectory from acute to persistent pain and that targeting these processes could prevent the development of persistent pain. In this review, we develop an integrative model and suggest novel interventions during early pain trajectories, based on predictions from this model.
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Affiliation(s)
- Christian Büchel
- Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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9
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Ray PR, Shiers S, Caruso JP, Tavares-Ferreira D, Sankaranarayanan I, Uhelski ML, Li Y, North RY, Tatsui C, Dussor G, Burton MD, Dougherty PM, Price TJ. RNA profiling of human dorsal root ganglia reveals sex differences in mechanisms promoting neuropathic pain. Brain 2023; 146:749-766. [PMID: 35867896 PMCID: PMC10169414 DOI: 10.1093/brain/awac266] [Citation(s) in RCA: 41] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 05/16/2022] [Accepted: 06/22/2022] [Indexed: 11/12/2022] Open
Abstract
Neuropathic pain is a leading cause of high-impact pain, is often disabling and is poorly managed by current therapeutics. Here we focused on a unique group of neuropathic pain patients undergoing thoracic vertebrectomy where the dorsal root ganglia is removed as part of the surgery allowing for molecular characterization and identification of mechanistic drivers of neuropathic pain independently of preclinical models. Our goal was to quantify whole transcriptome RNA abundances using RNA-seq in pain-associated human dorsal root ganglia from these patients, allowing comprehensive identification of molecular changes in these samples by contrasting them with non-pain-associated dorsal root ganglia. We sequenced 70 human dorsal root ganglia, and among these 50 met inclusion criteria for sufficient neuronal mRNA signal for downstream analysis. Our expression analysis revealed profound sex differences in differentially expressed genes including increase of IL1B, TNF, CXCL14 and OSM in male and CCL1, CCL21, PENK and TLR3 in female dorsal root ganglia associated with neuropathic pain. Coexpression modules revealed enrichment in members of JUN-FOS signalling in males and centromere protein coding genes in females. Neuro-immune signalling pathways revealed distinct cytokine signalling pathways associated with neuropathic pain in males (OSM, LIF, SOCS1) and females (CCL1, CCL19, CCL21). We validated cellular expression profiles of a subset of these findings using RNAscope in situ hybridization. Our findings give direct support for sex differences in underlying mechanisms of neuropathic pain in patient populations.
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Affiliation(s)
- Pradipta R Ray
- Department of Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA
| | - Stephanie Shiers
- Department of Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA
| | - James P Caruso
- Department of Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA.,Department of Neurological Surgery, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Diana Tavares-Ferreira
- Department of Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA
| | - Ishwarya Sankaranarayanan
- Department of Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA
| | - Megan L Uhelski
- Department of Pain Medicine, Division of Anesthesiology, MD Anderson Cancer Center, Houston, TX, USA
| | - Yan Li
- Department of Pain Medicine, Division of Anesthesiology, MD Anderson Cancer Center, Houston, TX, USA
| | - Robert Y North
- Department of Neurosurgery, MD Anderson Cancer Center, Houston, TX, USA
| | - Claudio Tatsui
- Department of Neurosurgery, MD Anderson Cancer Center, Houston, TX, USA
| | - Gregory Dussor
- Department of Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA
| | - Michael D Burton
- Department of Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA
| | - Patrick M Dougherty
- Department of Pain Medicine, Division of Anesthesiology, MD Anderson Cancer Center, Houston, TX, USA
| | - Theodore J Price
- Department of Neuroscience and Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA
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10
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Macionis V. Chronic pain and local pain in usually painless conditions including neuroma may be due to compressive proximal neural lesion. FRONTIERS IN PAIN RESEARCH 2023; 4:1037376. [PMID: 36890855 PMCID: PMC9986610 DOI: 10.3389/fpain.2023.1037376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 01/12/2023] [Indexed: 02/22/2023] Open
Abstract
It has been unexplained why chronic pain does not invariably accompany chronic pain-prone disorders. This question-driven, hypothesis-based article suggests that the reason may be varying occurrence of concomitant peripheral compressive proximal neural lesion (cPNL), e.g., radiculopathy and entrapment plexopathies. Transition of acute to chronic pain may involve development or aggravation of cPNL. Nociceptive hypersensitivity induced and/or maintained by cPNL may be responsible for all types of general chronic pain as well as for pain in isolated tissue conditions that are usually painless, e.g., neuroma, scar, and Dupuytren's fibromatosis. Compressive PNL induces focal neuroinflammation, which can maintain dorsal root ganglion neuron (DRGn) hyperexcitability (i.e., peripheral sensitization) and thus fuel central sensitization (i.e., hyperexcitability of central nociceptive pathways) and a vicious cycle of chronic pain. DRGn hyperexcitability and cPNL may reciprocally maintain each other, because cPNL can result from reflexive myospasm-induced myofascial tension, muscle weakness, and consequent muscle imbalance- and/or pain-provoked compensatory overuse. Because of pain and motor fiber damage, cPNL can worsen the causative musculoskeletal dysfunction, which further accounts for the reciprocity between the latter two factors. Sensitization increases nerve vulnerability and thus catalyzes this cycle. Because of these mechanisms and relatively greater number of neurons involved, cPNL is more likely to maintain DRGn hyperexcitability in comparison to distal neural and non-neural lesions. Compressive PNL is associated with restricted neural mobility. Intermittent (dynamic) nature of cPNL may be essential in chronic pain, because healed (i.e., fibrotic) lesions are physiologically silent and, consequently, cannot provide nociceptive input. Not all patients may be equally susceptible to develop cPNL, because occurrence of cPNL may vary as vary patients' predisposition to musculoskeletal impairment. Sensitization is accompanied by pressure pain threshold decrease and consequent mechanical allodynia and hyperalgesia, which can cause unusual local pain via natural pressure exerted by space occupying lesions or by their examination. Worsening of local pain is similarly explainable. Neuroma pain may be due to cPNL-induced axonal mechanical sensitivity and hypersensitivity of the nociceptive nervi nervorum of the nerve trunk and its stump. Intermittence and symptomatic complexity of cPNL may be the cause of frequent misdiagnosis of chronic pain.
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11
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Transition from acute to chronic pain: a misleading concept? Pain 2022; 163:e985-e988. [PMID: 35384919 DOI: 10.1097/j.pain.0000000000002631] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 03/08/2022] [Indexed: 11/27/2022]
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12
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Sex-dependent pain trajectories induced by prolactin require an inflammatory response for pain resolution. Brain Behav Immun 2022; 101:246-263. [PMID: 35065194 PMCID: PMC9173405 DOI: 10.1016/j.bbi.2022.01.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 01/11/2022] [Accepted: 01/16/2022] [Indexed: 11/23/2022] Open
Abstract
Pain development and resolution patterns in many diseases are sex-dependent. This study aimed to develop pain models with sex-dependent resolution trajectories, and identify factors linked to resolution of pain in females and males. Using different intra-plantar (i.pl.) treatment protocols with prolactin (PRL), we established models with distinct, sex-dependent patterns for development and resolution of pain. An acute PRL-evoked pain trajectory, in which hypersensitivity is fully resolved within 1 day, showed substantial transcriptional changes after pain-resolution in female and male hindpaws and in the dorsal root ganglia (DRG). This finding supports the notion that pain resolution is an active process. Prolonged treatment with PRL high dose (1 μg) evoked mechanical hypersensitivity that resolved within 5-7 days in mice of both sexes and exhibited a pro-inflammatory transcriptional response in the hindpaw, but not DRG, at the time point preceding resolution. Flow cytometry analysis linked pro-inflammatory responses in female hindpaws to macrophages/monocytes, especially CD11b+/CD64+/MHCII+ cell accumulation. Prolonged low dose PRL (0.1 μg) treatment caused non-resolving mechanical hypersensitivity only in females. This effect was independent of sensory neuronal PRLR and was associated with a lack of immune response in the hindpaw, although many genes underlying tissue damage were affected. We conclude that different i.pl. PRL treatment protocols generates distinct, sex-specific pain hypersensitivity resolution patterns. PRL-induced pain resolution is preceded by a pro-inflammatory macrophage/monocyte-associated response in the hindpaws of mice of both sexes. On the other hand, the absence of a peripheral inflammatory response creates a permissive condition for PRL-induced pain persistency in females.
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Time-Dependent Changes in Protein Composition of Medial Prefrontal Cortex in Rats with Neuropathic Pain. Int J Mol Sci 2022; 23:ijms23020955. [PMID: 35055141 PMCID: PMC8781622 DOI: 10.3390/ijms23020955] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/10/2022] [Accepted: 01/14/2022] [Indexed: 01/03/2023] Open
Abstract
Chronic pain is associated with time-dependent structural and functional reorganization of the prefrontal cortex that may reflect adaptive pain compensatory and/or maladaptive pain-promoting mechanisms. However, the molecular underpinnings of these changes and whether there are time-dependent relationships to pain progression are not well characterized. In this study, we analyzed protein composition in the medial prefrontal cortex (mPFC) of rats at two timepoints after spinal nerve ligation (SNL) using two-dimensional gel electrophoresis (2D-ELFO) and liquid chromatography with tandem mass spectrometry (LC–MS/MS). SNL, but not sham-operated, rats developed persistent tactile allodynia and thermal hyperalgesia, confirming the presence of experimental neuropathic pain. Two weeks after SNL (early timepoint), we identified 11 proteins involved in signal transduction, protein transport, cell homeostasis, metabolism, and apoptosis, as well as heat-shock proteins and chaperones that were upregulated by more than 1.5-fold compared to the sham-operated rats. Interestingly, there were only four significantly altered proteins identified at 8 weeks after SNL (late timepoint). These findings demonstrate extensive time-dependent modifications of protein expression in the rat mPFC under a chronic neuropathic pain state that might underlie the evolution of chronic pain characterized by early pain-compensatory and later aberrant mechanisms.
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14
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Walker SM. Developmental Mechanisms of CPSP: Clinical Observations and Translational Laboratory Evaluations. Can J Pain 2021; 6:49-60. [PMID: 35910395 PMCID: PMC9331197 DOI: 10.1080/24740527.2021.1999796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Understanding mechanisms that underly the transition from acute to chronic pain and identifying potential targets for preventing or minimizing this progression have specific relevance for chronic postsurgical pain (CPSP). Though it is clear that multiple psychosocial, family, and environmental factors may influence CPSP, this review will focus on parallels between clinical observations and translational laboratory studies investigating the acute and long-term effects of surgical injury on nociceptive pathways. This includes data related to alterations in sensitivity at different points along nociceptive pathways from the periphery to the brain; age- and sex-dependent mechanisms underlying the transition from acute to persistent pain; potential targets for preventive interventions; and the impact of prior surgical injury. Ongoing preclinical studies evaluating age- and sex-dependent mechanisms will also inform comparative efficacy and preclinical safety assessments of potential preventive pharmacological interventions aimed at reducing the risk of CPSP. In future clinical studies, more detailed and longitudinal peri-operative phenotyping with patient- and parent-reported chronic pain core outcomes, alongside more specialized evaluations of somatosensory function, modulation, and circuitry, may enhance understanding of individual variability in postsurgical pain trajectories and improve recognition and management of CPSP.
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Affiliation(s)
- Suellen M. Walker
- Clinical Neurosciences (Pain Research), Developmental Neurosciences, UCL GOS Institute of Child Health, London, UK; Department of Paediatric Anaesthesia and Pain Medicine, Great Ormond Street Hospital NHS Foundation Trust, London, UK
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15
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Reiss D, Maurin H, Audouard E, Martínez-Navarro M, Xue Y, Herault Y, Maldonado R, Cabañero D, Gaveriaux-Ruff C. Delta Opioid Receptor in Astrocytes Contributes to Neuropathic Cold Pain and Analgesic Tolerance in Female Mice. Front Cell Neurosci 2021; 15:745178. [PMID: 34602984 PMCID: PMC8483180 DOI: 10.3389/fncel.2021.745178] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 08/23/2021] [Indexed: 01/13/2023] Open
Abstract
Background: The delta opioid receptor (DOR) contributes to pain control, and a major challenge is the identification of DOR populations that control pain, analgesia, and tolerance. Astrocytes are known as important cells in the pathophysiology of chronic pain, and many studies report an increased prevalence of pain in women. However, the implication of astrocytic DOR in neuropathic pain and analgesia, as well as the influence of sex in this receptor activity, remains unknown. Experimental Approach: We developed a novel conditional knockout (cKO) mouse line wherein DOR is deleted in astrocytes (named GFAP-DOR-KO), and investigated neuropathic mechanical allodynia as well as analgesia and analgesic tolerance in mutant male and female mice. Neuropathic cold allodynia was also characterized in mice of both sexes lacking DOR either in astrocytes or constitutively. Results: Neuropathic mechanical allodynia was similar in GFAP-DOR-KO and floxed DOR control mice, and the DOR agonist SNC80 produced analgesia in mutant mice of both sexes. Interestingly, analgesic tolerance developed in cKO males and was abolished in cKO females. Cold neuropathic allodynia was reduced in mice with decreased DOR in astrocytes. By contrast, cold allodynia was exacerbated in full DOR KO females. Conclusions: These findings show that astrocytic DOR has a prominent role in promoting cold allodynia and analgesic tolerance in females, while overall DOR activity was protective. Altogether this suggests that endogenous- and exogenous-mediated DOR activity in astrocytes worsens neuropathic allodynia while DOR activity in other cells attenuates this form of pain. In conclusion, our results show a sex-specific implication of astrocytic DOR in neuropathic pain and analgesic tolerance. These findings open new avenues for developing tailored DOR-mediated analgesic strategies.
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Affiliation(s)
- David Reiss
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
| | - Hervé Maurin
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
| | - Emilie Audouard
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
| | - Miriam Martínez-Navarro
- Laboratory of Neuropharmacology, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Yaping Xue
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
| | - Yann Herault
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
| | - Rafael Maldonado
- Laboratory of Neuropharmacology, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - David Cabañero
- Laboratory of Neuropharmacology, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
- Institute of Research, Development and Innovation in Healthcare Biotechnology of Elche (IDiBE), Universidad Miguel Hernández Elche, Alicante, Spain
| | - Claire Gaveriaux-Ruff
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
- Ecole Supérieure de Biotechnologie de Strasbourg, Illkirch, France
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16
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Kavelaars A, Heijnen CJ. T Cells as Guardians of Pain Resolution. Trends Mol Med 2021; 27:302-313. [PMID: 33431239 PMCID: PMC8005447 DOI: 10.1016/j.molmed.2020.12.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 11/20/2020] [Accepted: 12/10/2020] [Indexed: 01/08/2023]
Abstract
Despite successful research efforts aimed at understanding pain mechanisms, there is still no adequate treatment for many patients suffering from chronic pain. The contribution of neuroinflammation to chronic pain is widely acknowledged. Here, we summarize findings indicating that T cells play a key role in the suppression of pain. An active contribution of the immune system to resolution of pain may explain why immunosuppressive drugs are often not sufficient to control pain. This would also imply that dysregulation of certain immune functions promote transition to chronic pain. Conversely, stimulating the endogenous immune-mediated resolution pathways may provide a potent approach to treat chronic pain.
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Affiliation(s)
- Annemieke Kavelaars
- Laboratories of Neuroimmunology, Department of Symptom Research, Division of Internal Medicine, University of Texas, M.D. Anderson Cancer Center, Zayed Building, M.D. Anderson Boulevard, Houston, TX 77030, USA.
| | - Cobi J Heijnen
- Laboratories of Neuroimmunology, Department of Symptom Research, Division of Internal Medicine, University of Texas, M.D. Anderson Cancer Center, Zayed Building, M.D. Anderson Boulevard, Houston, TX 77030, USA.
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17
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Puntillo F, Giglio M, Paladini A, Perchiazzi G, Viswanath O, Urits I, Sabbà C, Varrassi G, Brienza N. Pathophysiology of musculoskeletal pain: a narrative review. Ther Adv Musculoskelet Dis 2021; 13:1759720X21995067. [PMID: 33737965 PMCID: PMC7934019 DOI: 10.1177/1759720x21995067] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 01/27/2021] [Indexed: 02/06/2023] Open
Abstract
Musculoskeletal pain (excluding bone cancer pain) affects more than 30% of the global population and imposes an enormous burden on patients, families, and caregivers related to functional limitation, emotional distress, effects on mood, loss of independence, and reduced quality of life. The pathogenic mechanisms of musculoskeletal pain relate to the differential sensory innervation of bones, joints, and muscles as opposed to skin and involve a number of peripheral and central nervous system cells and mediators. The interplay of neurons and non-neural cells (e.g. glial, mesenchymal, and immune cells) amplifies and sensitizes pain signals in a manner that leads to cortical remodeling. Moreover, sex, age, mood, and social factors, together with beliefs, thoughts, and pain behaviors influence the way in which musculoskeletal pain manifests and is understood and assessed. The aim of this narrative review is to summarize the different pathogenic mechanisms underlying musculoskeletal pain and how these mechanisms interact to promote the transition from acute to chronic pain.
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Affiliation(s)
- Filomena Puntillo
- Department of Interdisciplinary Medicine, 'Aldo Moro' University of Bari, Piazza G. Cesare 11, Bari 70124, Italy
| | - Mariateresa Giglio
- Anesthesia, Intensive Care and Pain Unit, Policlinico Hospital, Bari, Italy
| | | | - Gaetano Perchiazzi
- Department of Surgical Science, Hedenstierna Laboratory, Uppsala University, Uppsala, Sweden
| | - Omar Viswanath
- Department of Anesthesiology, Creighton University School of Medicine, Omaha, NE, USA
| | - Ivan Urits
- Department of Anesthesia, Beth Israel Deaconess Med Center, Harvard Medical School, Boston, MA, USA
| | - Carlo Sabbà
- Department of Interdisciplinary Medicine, 'Aldo Moro' University of Bari, Bari, Italy
| | | | - Nicola Brienza
- Department of Interdisciplinary Medicine, 'Aldo Moro' University of Bari, Bari, Italy
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18
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Callan N, Hanes D, Bradley R. Early evidence of efficacy for orally administered SPM-enriched marine lipid fraction on quality of life and pain in a sample of adults with chronic pain. J Transl Med 2020; 18:401. [PMID: 33087142 PMCID: PMC7579794 DOI: 10.1186/s12967-020-02569-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 10/12/2020] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Marine lipids contain omega-3 fatty acids that can be metabolized into anti-inflammatory and pro-resolving mediators-namely 17-HDHA and 18-HEPE-which can serve as modulators of the pain experience. The purpose of this study was to determine the impact of 4 weeks of oral supplementation with a fractionated marine lipid concentration, standardized to 17-HDHA and 18-HEPE, on health-related quality of life and inflammation in adults with chronic pain. METHODS This study was a prospective, non-randomized, open-label clinical trial. Forty-four adults with ≥ moderate pain intensity for at least 3 months were recruited. The primary outcome was change in health-related quality of life (QOL) using the Patient Reported Outcomes Measurement Information System-43 Profile (PROMIS-43) and the American Chronic Pain Association (ACPA) QOL scale. Exploratory outcomes assessed safety and tolerability, changes in anxiety and depression, levels of pain intensity and interference, patient satisfaction, and impression of change. Changes in blood biomarkers of inflammation (hs-CRP and ESR) were also explored. RESULTS Outcome measures were collected at Baseline, Week 2, and Week 4 (primary endpoint). At Week 4, PROMIS-43 QOL subdomains changed with significance from baseline (p < 0.05), with borderline changes in the ACPA Quality of Life scale (p < 0.052). Exploratory analyses revealed significant changes (p < 0.05) in all measures of pain intensity, pain interference, depression, and anxiety. There were no statistically significant changes in either hs-CRP or ESR, which stayed within normal limits. CONCLUSION We conclude that oral supplementation with a fractionated marine lipid concentration standardized to 17-HDHA and 18-HEPE may improve quality of life, reduce pain intensity and interference, and improve mood within 4 weeks in adults with chronic pain. The consistency and magnitude of these results support the need for placebo-controlled clinical trials of marine lipid concentrations standardized to 17-HDHA and 18-HEPE. Trial registration ClinicalTrials.gov: Influence of an Omega-3 SPM Supplement on Quality of Life, NCT02683850. Registered 17 February 2016-retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02683850 .
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Affiliation(s)
- Nini Callan
- National University of Natural Medicine, Helfgott Research Institute, 2220 SW 1st Ave, Portland, OR, 97201, USA
| | - Doug Hanes
- National University of Natural Medicine, Helfgott Research Institute, 2220 SW 1st Ave, Portland, OR, 97201, USA
| | - Ryan Bradley
- National University of Natural Medicine, Helfgott Research Institute, 2220 SW 1st Ave, Portland, OR, 97201, USA. .,Herbert Wertheim School of Public Health, University of California, San Diego, La Jolla, CA, USA.
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