1
|
Tian J, Shen Z, Sutherland BA, Cicuttini F, Jones G, Pan F. Chronic pain in multiple sites is associated with cardiovascular dysfunction: an observational UK Biobank cohort study. Br J Anaesth 2024; 133:605-614. [PMID: 39003202 DOI: 10.1016/j.bja.2024.06.021] [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: 02/03/2024] [Revised: 05/30/2024] [Accepted: 06/05/2024] [Indexed: 07/15/2024] Open
Abstract
BACKGROUND Chronic pain is associated with development of cardiovascular disease. We investigated the association between how widespread chronic pain is and the development of cardiovascular dysfunction. METHODS We analysed data from participants enrolled in the UK Biobank study who underwent examinations at baseline, plus first follow-up and two imaging visits. Pain sites (including hip, knee, back, neck/shoulder, or 'all over the body') and pain duration were recorded at each visit. Chronic pain was defined as pain lasting for ≥3 months. Participants were categorised into six groups: no chronic pain, chronic pain in one, two, three, or four sites, or 'all over the body'. Arterial stiffness index was measured at each time point. Carotid intima-media thickness, cardiac index, and left ventricular ejection fraction (LVEF) were measured using ultrasound and heart MRI at two additional imaging visits in a subset of participants. Mixed-effect linear regression models were used for the analyses. RESULTS The number of chronic pain sites was directly related to increased arterial stiffness index (n=159,360; β=0.06 per one site increase, 95% confidence interval 0.04 to 0.08). In 23,899 participants, lower LVEF was associated with widespread chronic pain (β=-0.17 per one site increase, 95% confidence interval -0.27 to -0.07). The number of chronic pain sites was not associated with carotid intima-media thickness (n=30,628) or cardiac index (n=23,899). CONCLUSION A greater number of chronic pain sites is associated with increased arterial stiffness and poorer cardiac function, suggesting that widespread chronic pain is an important contributor to cardiovascular dysfunction.
Collapse
Affiliation(s)
- Jing Tian
- Cardiovascular Research Flagship, Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
| | - Ziyuan Shen
- Musculoskeletal Health and Disease Theme, Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia; Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, AN, China
| | - Brad A Sutherland
- Tasmanian School of Medicine, University of Tasmania, Hobart, TAS, Australia
| | - Flavia Cicuttini
- School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
| | - Graeme Jones
- Musculoskeletal Health and Disease Theme, Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
| | - Feng Pan
- Musculoskeletal Health and Disease Theme, Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia.
| |
Collapse
|
2
|
Abdolmohammadi-Vahid S, Baradaran B, Sadeghi A, Bezemer GFG, Kiaee F, Adcock IM, Folkerts G, Garssen J, Mortaz E. Effects of toll-like receptor agonists and SARS-CoV-2 antigens on interferon (IFN) expression by peripheral blood CD3 + T cells from COVID-19 patients. Exp Mol Pathol 2024; 137:104897. [PMID: 38691979 DOI: 10.1016/j.yexmp.2024.104897] [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: 06/14/2023] [Revised: 03/09/2024] [Accepted: 04/22/2024] [Indexed: 05/03/2024]
Abstract
BACKGROUND Signaling by toll-like receptors (TLRs) initiates important immune responses against viral infection. The role of TLRs in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is not well elucidated. Thus, we investigated the interaction of TLRs agonists and SARS-COV-2 antigens with immune cells in vitro. MATERIAL & METHODS 30 coronavirus disease 2019 (COVID-19) patients (15 severe and 15 moderate) and 10 age and sex-matched healthy control (HC) were enrolled. Peripheral blood mononuclear cells (PBMCs) were isolated and activated with TLR3, 7, 8, and 9 agonists, the spike protein (SP) of SARS-CoV-2, and the receptor binding domain (RBD) of SP. Frequencies of CD3+IFN-β+ T cells, and CD3+IFN-γ+ T cells were evaluated by flow cytometry. Interferon (IFN)-β gene expression was assessed by qRT-PCR. RESULTS The frequency of CD3+IFN-β+ T cells was higher in PBMCs from moderate (p < 0.0001) and severe (p = 0.009) patients at baseline in comparison with HCs. The highest increase in the frequency of CD3+IFN-β+ T cells in cell from moderate patients was induced by TLR8 agonist and SP (p < 0.0001 for both) when compared to HC, while, the highest increase of the frequency of CD3+IFN-β+ T cells in sample of severe patients was seen with TLR8 and TLR7 agonists (both p = 0.002). The frequency of CD3+IFN-γ+ T cells was significantly increased upon stimulation with TLR agonists in cell from patients with moderate and severe COVID-19, compared with HC (all p < 0.01), except with TLR7 and TLR8 agonists. The TLR8 agonist did not significantly increase the frequency of CD3+IFN-γ+ T cells in PBMCs of severe patients, but did so in cells from patients with moderate disease (p = 0.01). Moreover, IFN-β gene expression was significantly upregulated in CD3+T cells from moderate (p < 0.0001) and severe (p = 0.002) COVID-19 patients, compared to HC after stimulation with the TLR8 agonist, while, stimulation of T cells with SP, significantly up-regulated IFN-β mRNA expression in cells from patients with moderate (p = 0.0003), but not severe disease. CONCLUSION Stimulation of PBMCs from COVID-19 patients, especially patients with moderate disease, with TLR8 agonist and SP increased the frequency of IFN-β-producing T cells and IFN-β gene expression.
Collapse
Affiliation(s)
| | - Behzad Baradaran
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Armin Sadeghi
- Tuberculosis and Lung Disease Research Center of Tabriz University of Medical Sciences, Tabriz, Iran
| | - Gillina F G Bezemer
- Division of Pharmacology, Faculty of Science, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, the Netherlands; Impact Station, Hilversum, the Netherlands
| | - Fatemeh Kiaee
- Department of Immunology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ian M Adcock
- Respiratory Section, Faculty of Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom; Immune Health Program at Hunter Medical Research Institute and the College of Health and Medicine at the University of Newcastle, NSW, Australia
| | - Gert Folkerts
- Division of Pharmacology, Faculty of Science, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, the Netherlands
| | - Johan Garssen
- Division of Pharmacology, Faculty of Science, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, the Netherlands
| | - Esmaeil Mortaz
- Department of Immunology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
3
|
Rodríguez-Palma EJ, Huerta de la Cruz S, Islas-Espinoza AM, Castañeda-Corral G, Granados-Soto V, Khanna R. Nociplastic pain mechanisms and toll-like receptors as promising targets for its management. Pain 2024:00006396-990000000-00571. [PMID: 38595206 DOI: 10.1097/j.pain.0000000000003238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 02/29/2024] [Indexed: 04/11/2024]
Abstract
ABSTRACT Nociplastic pain, characterized by abnormal pain processing without an identifiable organic cause, affects a significant portion of the global population. Unfortunately, current pharmacological treatments for this condition often prove ineffective, prompting the need to explore new potential targets for inducing analgesic effects in patients with nociplastic pain. In this context, toll-like receptors (TLRs), known for their role in the immune response to infections, represent promising opportunities for pharmacological intervention because they play a relevant role in both the development and maintenance of pain. Although TLRs have been extensively studied in neuropathic and inflammatory pain, their specific contributions to nociplastic pain remain less clear, demanding further investigation. This review consolidates current evidence on the connection between TLRs and nociplastic pain, with a specific focus on prevalent conditions like fibromyalgia, stress-induced pain, sleep deprivation-related pain, and irritable bowel syndrome. In addition, we explore the association between nociplastic pain and psychiatric comorbidities, proposing that modulating TLRs can potentially alleviate both pain syndromes and related psychiatric disorders. Finally, we discuss the potential sex differences in TLR signaling, considering the higher prevalence of nociplastic pain among women. Altogether, this review aims to shed light on nociplastic pain, its underlying mechanisms, and its intriguing relationship with TLR signaling pathways, ultimately framing the potential therapeutic role of TLRs in addressing this challenging condition.
Collapse
Affiliation(s)
- Erick J Rodríguez-Palma
- Department of Pharmacology and Therapeutics, College of Medicine, University of Florida, Gainesville, FL, United States
- Neurobiology of Pain Laboratory, Departamento de Farmacobiología, Cinvestav, South Campus, Mexico City, Mexico
| | | | - Ana M Islas-Espinoza
- Neurobiology of Pain Laboratory, Departamento de Farmacobiología, Cinvestav, South Campus, Mexico City, Mexico
| | | | - Vinicio Granados-Soto
- Neurobiology of Pain Laboratory, Departamento de Farmacobiología, Cinvestav, South Campus, Mexico City, Mexico
| | - Rajesh Khanna
- Department of Pharmacology and Therapeutics, College of Medicine, University of Florida, Gainesville, FL, United States
| |
Collapse
|
4
|
Mustafa S, Bajic JE, Barry B, Evans S, Siemens KR, Hutchinson MR, Grace PM. One immune system plays many parts: The dynamic role of the immune system in chronic pain and opioid pharmacology. Neuropharmacology 2023; 228:109459. [PMID: 36775098 PMCID: PMC10015343 DOI: 10.1016/j.neuropharm.2023.109459] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 02/06/2023] [Accepted: 02/08/2023] [Indexed: 02/12/2023]
Abstract
The transition from acute to chronic pain is an ongoing major problem for individuals, society and healthcare systems around the world. It is clear chronic pain is a complex multidimensional biological challenge plagued with difficulties in pain management, specifically opioid use. In recent years the role of the immune system in chronic pain and opioid pharmacology has come to the forefront. As a highly dynamic and versatile network of cells, tissues and organs, the immune system is perfectly positioned at the microscale level to alter nociception and drive structural adaptations that underpin chronic pain and opioid use. In this review, we highlight the need to understand the dynamic and adaptable characteristics of the immune system and their role in the transition, maintenance and resolution of chronic pain. The complex multidimensional interplay of the immune system with multiple physiological systems may provide new transformative insight for novel targets for clinical management and treatment of chronic pain. This article is part of the Special Issue on "Opioid-induced changes in addiction and pain circuits".
Collapse
Affiliation(s)
- Sanam Mustafa
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia; Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, The University of Adelaide, Adelaide, SA, Australia; Davies Livestock Research Centre, The University of Adelaide, Roseworthy, SA, Australia.
| | - Juliana E Bajic
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia; Davies Livestock Research Centre, The University of Adelaide, Roseworthy, SA, Australia
| | - Benjamin Barry
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia
| | - Samuel Evans
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia; Davies Livestock Research Centre, The University of Adelaide, Roseworthy, SA, Australia
| | - Kariel R Siemens
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia
| | - Mark R Hutchinson
- School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia; Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, The University of Adelaide, Adelaide, SA, Australia; Davies Livestock Research Centre, The University of Adelaide, Roseworthy, SA, Australia
| | - Peter M Grace
- Laboratories of Neuroimmunology, Department of Symptom Research, University of Texas MD Anderson Cancer Center, Houston, TX, USA; MD Anderson Pain Research Consortium, Houston, TX, USA
| |
Collapse
|
5
|
Lutke Schipholt IJ, Scholten-Peeters GGM, Koop MA, Bonnet P, Bontkes HJ, Coppieters MW. Systemic neuroimmune responses in people with non-specific neck pain and cervical radiculopathy, and associations with clinical, psychological, and lifestyle factors. Front Mol Neurosci 2022; 15:1003821. [PMID: 36311017 PMCID: PMC9608367 DOI: 10.3389/fnmol.2022.1003821] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 09/20/2022] [Indexed: 08/09/2023] Open
Abstract
Neuroimmune responses remain understudied in people with neck pain. This study aimed to (1) compare a broad range of systemic neuroimmune responses in people with non-specific neck pain (N = 112), cervical radiculopathy (N = 25), and healthy participants (N = 23); and (2) explore their associations with clinical, psychological and lifestyle factors. Quantification of systemic neuroimmune responses involved ex vivo serum and in vitro evoked-release levels of inflammatory markers, and characterization of white blood cell phenotypes. Inflammatory indices were calculated to obtain a measure of total immune status and were considered the main outcomes. Differences between groups were tested using analyses of covariance (ANCOVA) and multivariable regression models. Compared to healthy participants, the ex vivo pro-inflammatory index was increased in people with non-specific neck pain (β = 0.70, p = 0.004) and people with cervical radiculopathy (β = 0.64, p = 0.04). There was no difference between non-specific neck pain and cervical radiculopathy (β = 0.23, p = 0.36). Compared to non-specific neck pain, people with cervical radiculopathy showed lower numbers of monocytes (β = -59, p = 0.01). There were no differences between groups following in vitro whole blood stimulation (p ≥ 0.23) or other differences in the number and phenotype of white blood cells (p ≥ 0.07). The elevated ex vivo neuroimmune responses in people with non-specific neck pain and radiculopathy support the contention that these conditions encompass inflammatory components that can be measured systemically. There were multiple significant associations with clinical, psychological and lifestyle factors, such as pain intensity (β = 0.25) and anxiety (β = 0.23) in non-specific neck pain, visceral adipose tissue (β = 0.43) and magnification (β = 0.59) in cervical radiculopathy, and smoking (β = 0.59) and visceral adipose tissue (β = 0.52) in healthy participants. These associations were modified by sex, indicating different neuroimmune associations for females and males.
Collapse
Affiliation(s)
- Ivo J. Lutke Schipholt
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Laboratory Medical Immunology, Department of Clinical Chemistry, Amsterdam University Medical Center, Amsterdam, Netherlands
- Department of Rehabilitation Medicine, Amsterdam University Medical Centre, Amsterdam, Netherlands
| | - Gwendolyne G. M. Scholten-Peeters
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Meghan A. Koop
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Laboratory Medical Immunology, Department of Clinical Chemistry, Amsterdam University Medical Center, Amsterdam, Netherlands
| | - Petra Bonnet
- Laboratory Medical Immunology, Department of Clinical Chemistry, Amsterdam University Medical Center, Amsterdam, Netherlands
| | - Hetty J. Bontkes
- Laboratory Medical Immunology, Department of Clinical Chemistry, Amsterdam University Medical Center, Amsterdam, Netherlands
| | - Michel W. Coppieters
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Menzies Health Institute Queensland, Griffith University, Brisbane, QLD, Australia
| |
Collapse
|
6
|
Madden VJ, Msolo N, Mqadi L, Lesosky M, Bedwell GJ, Hutchinson MR, Peter JG, Parker R, Schrepf A, Edwards RR, Joska JA. Study protocol: an observational study of distress, immune function and persistent pain in HIV. BMJ Open 2022; 12:e059723. [PMID: 36691234 PMCID: PMC9171212 DOI: 10.1136/bmjopen-2021-059723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 04/28/2022] [Indexed: 01/27/2023] Open
Abstract
INTRODUCTION Many people with HIV report both distress and pain. The relationship between distress and pain is bidirectional, but the mechanisms by which distress exacerbates pain are unclear. The inflammatory response to challenge (inflammatory reactivity, IR) may be a partial mediator, given that neuroimmune interactions provide a substrate for IR to also influence neurological reactivity and, thus, pain-related neural signalling. This prospective, observational, case-control study will characterise the relationships between distress, IR, pain-related signalling as captured by induced secondary hyperalgesia (SH), and pain, in people with HIV who report persistent pain (PP) (cases) or no pain (controls). METHODS AND ANALYSIS One hundred people with suppressed HIV, reporting either PP or no pain, will be assessed two or four times over 6 months. The primary outcomes are distress (Hopkins 25-item symptom checklist), IR (multiplex assay after LPS challenge), and PP (Brief Pain Inventory), assessed at the baseline timepoint, although each will also be assessed at follow-up time points. Induced SH will be assessed in a subsample of 60 participants (baseline timepoint only). To test the hypothesis that IR partly mediates the relationship between distress and pain, mediation analysis will use the baseline data from the PP group to estimate direct and indirect contributions of distress and IR to pain. To test the hypothesis that IR is positively associated with SH, data from the subsample will be analysed with generalised mixed effects models to estimate the association between IR and group membership, with SH as the dependent variable. ETHICS AND DISSEMINATION Information obtained from this study will be published in peer-reviewed journals and presented at scientific meetings. The study has been approved by the Human Research Ethics Committee of the University of Cape Town (approval number: 764/2019) and the City of Cape Town (ref: 24699). TRIAL REGISTRATION NUMBER NCT04757987.
Collapse
Affiliation(s)
- Victoria J Madden
- Pain Research Team, Department of Anaesthesia and Perioperative Medicine, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
- HIV Mental Health Research Unit, Department of Psychiatry and Mental Health, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Ncumisa Msolo
- Pain Research Team, Department of Anaesthesia and Perioperative Medicine, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Luyanduthando Mqadi
- Pain Research Team, Department of Anaesthesia and Perioperative Medicine, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
- HIV Mental Health Research Unit, Department of Psychiatry and Mental Health, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Maia Lesosky
- Division of Epidemiology & Biostatistics, School of Public Health and Family Medicine, University of Cape Town, Cape Town, South Africa
| | - Gillian J Bedwell
- Pain Research Team, Department of Anaesthesia and Perioperative Medicine, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Mark R Hutchinson
- Adelaide Medical School, The University of Adelaide, Adelaide, South Australia, Australia
| | - Jonathan Grant Peter
- Division of Allergy and Clinical Immunology, Department of Medicine, Groote Schuur Hospital, University of Cape Town, Rondebosch, South Africa
- Allergy and Immunology Unit, University of Cape Town Lung Institute, University of Cape Town, Cape Town, South Africa
| | - Romy Parker
- Pain Research Team, Department of Anaesthesia and Perioperative Medicine, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Andrew Schrepf
- Chronic Pain and Fatigue Research Center, Department of Anesthesiology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Robert R Edwards
- Department of Anesthesiology, Perioperative, and Pain Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - John A Joska
- HIV Mental Health Research Unit, Department of Psychiatry and Mental Health, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| |
Collapse
|
7
|
Johnston CH, Whittaker AL, Franklin SH, Hutchinson MR. The Neuroimmune Interface and Chronic Pain Through the Lens of Production Animals. Front Neurosci 2022; 16:887042. [PMID: 35663552 PMCID: PMC9160236 DOI: 10.3389/fnins.2022.887042] [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: 03/01/2022] [Accepted: 04/13/2022] [Indexed: 11/13/2022] Open
Abstract
Communication between the central nervous system (CNS) and the immune system has gained much attention for its fundamental role in the development of chronic and pathological pain in humans and rodent models. Following peripheral nerve injury, neuroimmune signaling within the CNS plays an important role in the pathophysiological changes in pain sensitivity that lead to chronic pain. In production animals, routine husbandry procedures such as tail docking and castration, often involve some degree of inflammation and peripheral nerve injury and consequently may lead to chronic pain. Our understanding of chronic pain in animals is limited by the difficulty in measuring this pathological pain state. In light of this, we have reviewed the current understanding of chronic pain in production animals. We discuss our ability to measure pain and the implications this has on animal welfare and production outcomes. Further research into the neuroimmune interface in production animals will improve our fundamental understanding of chronic pain and better inform human clinical pain management and animal husbandry practices and interventions.
Collapse
Affiliation(s)
- Charlotte H. Johnston
- Faculty of Health Sciences, Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Alexandra L. Whittaker
- School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy, SA, Australia
| | - Samantha H. Franklin
- School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy, SA, Australia
- Equine Health and Performance Centre, University of Adelaide, Roseworthy, SA, Australia
| | - Mark R. Hutchinson
- Faculty of Health Sciences, Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, University of Adelaide, Adelaide, SA, Australia
- Davies Livestock Research Centre, University of Adelaide, Roseworthy, SA, Australia
| |
Collapse
|
8
|
Thomas JHL, Lui L, Abell A, Tieu W, Somogyi AA, Bajic JE, Hutchinson MR. Toll-like receptors change morphine-induced antinociception, tolerance and dependence: Studies using male and female TLR and signalling gene KO mice. Brain Behav Immun 2022; 102:71-85. [PMID: 35131445 DOI: 10.1016/j.bbi.2022.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 12/22/2021] [Accepted: 02/01/2022] [Indexed: 12/13/2022] Open
Abstract
Toll-like receptors (TLR) have been proposed as a site of action that alters opioid pharmacodynamics. However, a comprehensive assessment of acute opioid antinociception, tolerance and withdrawal behaviours in genetic null mutant strains with altered innate immune signalling has not been performed. Nor has the impact of genetic deletion of TLR2/4 on high-affinity opioid receptor binding. Here we show that diminished TLR signalling potentiates acute morphine antinociception equally in male and female mice. However, only male TIR8 null mutant mice showed reduced morphine analgesia. Analgesic tolerance was prevented in TLR2 and TLR4 null mutants, but not MyD88 animals. Withdrawal behaviours were only protected in TLR2-/- mice. In silico docking simulations revealed opioid ligands bound preferentially to the LPS binding pocket of MD-2 rather than TLR4. There was no binding of [3H](-)-naloxone or [3H]diprenorphine to TLR4 in the concentrations explored. These data confirm that opioids have high efficacy activity at innate immune pattern recognition binding sites but do not bind to TLR4 and identify critical pathway and sex-specific effects of the complex innate immune signalling contributions to opioid pharmacodynamics. These data further support the behavioural importance of the TLR-opioid interaction but fail to demonstrate direct evidence for high-affinity binding of the TLR4 signalling complex to ligands.
Collapse
Affiliation(s)
- Jacob H L Thomas
- Discipline of Pharmacology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; Discipline of Physiology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
| | - Liang Lui
- Discipline of Pharmacology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
| | - Andrew Abell
- Discipline of Physiology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; ARC Centre for Nanoscale BioPhotonics, University of Adelaide, SA 5005, Australia
| | - William Tieu
- Discipline of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia
| | - Andrew A Somogyi
- Discipline of Pharmacology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
| | - Juliana E Bajic
- Discipline of Physiology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; ARC Centre for Nanoscale BioPhotonics, University of Adelaide, SA 5005, Australia
| | - Mark R Hutchinson
- Discipline of Physiology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; ARC Centre for Nanoscale BioPhotonics, University of Adelaide, SA 5005, Australia.
| |
Collapse
|
9
|
Zhang L, Stamer UM, Huang MYY, Stüber F. Interactions between the Nociceptin and Toll-like Receptor Systems. Cells 2022; 11:1085. [PMID: 35406649 PMCID: PMC8997556 DOI: 10.3390/cells11071085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/14/2022] [Accepted: 03/20/2022] [Indexed: 02/01/2023] Open
Abstract
Nociceptin and the nociceptin receptor (NOP) have been described as targets for treatment of pain and inflammation, whereas toll-like receptors (TLRs) play key roles in inflammation and impact opioid receptors and endogenous opioids expression. In this study, interactions between the nociceptin and TLR systems were investigated. Human THP-1 cells were cultured with or without phorbol myristate acetate (PMA 5 ng/mL), agonists specific for TLR2 (lipoteichoic acid, LTA 10 µg/mL), TLR4 (lipopolysaccharide, LPS 100 ng/mL), TLR7 (imiquimod, IMQ 10 µg/mL), TLR9 (oligonucleotide (ODN) 2216 1 µM), PMA+TLR agonists, or nociceptin (0.01−100 nM). Prepronociceptin (ppNOC), NOP, and TLR mRNAs were quantified by RT-qPCR. Proteins were measured using flow cytometry. PMA upregulated ppNOC mRNA, intracellular nociceptin, and cell membrane NOP proteins (all p < 0.05). LTA and LPS prevented PMA’s upregulating effects on ppNOC mRNA and nociceptin protein (both p < 0.05). IMQ and ODN 2216 attenuated PMA’s effects on ppNOC mRNA. PMA, LPS, IMQ, and ODN 2216 increased NOP protein levels (all p < 0.05). PMA+TLR agonists had no effects on NOP compared to PMA controls. Nociceptin dose-dependently suppressed TLR2, TLR4, TLR7, and TLR9 proteins (all p < 0.01). Antagonistic effects observed between the nociceptin and TLR systems suggest that the nociceptin system plays an anti-inflammatory role in monocytes under inflammatory conditions.
Collapse
Affiliation(s)
- Lan Zhang
- Department of Anaesthesiology and Pain Medicine, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland; (U.M.S.); (M.Y.-Y.H.); (F.S.)
- Department for BioMedical Research, University of Bern, 3008 Bern, Switzerland
| | - Ulrike M. Stamer
- Department of Anaesthesiology and Pain Medicine, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland; (U.M.S.); (M.Y.-Y.H.); (F.S.)
- Department for BioMedical Research, University of Bern, 3008 Bern, Switzerland
| | - Melody Ying-Yu Huang
- Department of Anaesthesiology and Pain Medicine, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland; (U.M.S.); (M.Y.-Y.H.); (F.S.)
- Department for BioMedical Research, University of Bern, 3008 Bern, Switzerland
| | - Frank Stüber
- Department of Anaesthesiology and Pain Medicine, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland; (U.M.S.); (M.Y.-Y.H.); (F.S.)
- Department for BioMedical Research, University of Bern, 3008 Bern, Switzerland
| |
Collapse
|
10
|
Lutke Schipholt IJ, Scholten-Peeters G, Bontkes H, Coppieters MW. Neuroimmune responses following joint mobilisation and manipulation in people with persistent neck pain: a protocol for a randomised placebo-controlled trial. BMJ Open 2022; 12:e055748. [PMID: 35260459 PMCID: PMC8905979 DOI: 10.1136/bmjopen-2021-055748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
INTRODUCTION Joint mobilisation and manipulation often results in immediate pain relief in people with neck pain. However, the biological mechanisms behind pain relief are largely unknown. There is preliminary evidence that joint mobilisation and manipulation lessens the upregulated neuroimmune responses in people with persistent neck pain. METHODS AND ANALYSIS This study protocol describes a randomised placebo-controlled trial to investigate whether joint mobilisation and manipulation influence neuroimmune responses in people with persistent neck pain. People with persistent neck pain (N=100) will be allocated, in a randomised and concealed manner, to the experimental or control group (ratio 3:1). Short-term (ie, baseline, immediately after and 2 hours after the intervention) neuroimmune responses will be assessed, such as inflammatory marker concentration following in vitro stimulation of whole blood cells, systemic inflammatory marker concentrations directly from blood samples, phenotypic analysis of peripheral blood mononuclear cells and serum cortisol. Participants assigned to the experimental group (N=75) will receive cervical mobilisations targeting the painful and/or restricted cervical segments and a distraction manipulation of the cervicothoracic junction. Participants assigned to the control group (N=25) will receive a placebo mobilisation and placebo manipulation. Using linear mixed models, the short-term neuroimmune responses will be compared (1) between people in the experimental and control group and (2) within the experimental group, between people who experience a good outcome and those with a poor outcome. Furthermore, the association between the short-term neuroimmune responses and pain relief following joint mobilisation and manipulation will be tested in the experimental group. ETHICS AND DISSEMINATION This trial is approved by the Medical Ethics Committee of Amsterdam University Medical Centre, location VUmc (Approval number: 2018.181). TRIAL REGISTRATION NUMBER NL6575 (trialregister.nl.
Collapse
Affiliation(s)
- Ivo J Lutke Schipholt
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Department of Clinical Chemistry, Laboratory Medical Immunology, Amsterdam UMC, Location VU Medical Centre, Amsterdam, Netherlands
| | - Gwendolyne Scholten-Peeters
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Hetty Bontkes
- Department of Clinical Chemistry, Laboratory Medical Immunology, Amsterdam UMC, Location VU Medical Centre, Amsterdam, Netherlands
| | - Michel W Coppieters
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Menzies Health Institute Queensland, Griffith University, Brisbane & Gold Coast, Queensland, Australia
| |
Collapse
|
11
|
Somogyi AA, Musolino ST, Barratt DT. New pharmacological perspectives and therapeutic options for opioids: Differences matter. Anaesth Intensive Care 2022; 50:127-140. [PMID: 35112584 DOI: 10.1177/0310057x211063891] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Opioids remain the major drug class for the treatment of acute, chronic and cancer pain, but have major harmful effects such as dependence and opioid-induced ventilatory impairment. Although no new typical opioids have come onto the market in the past almost 50 years, a plethora of new innovative formulations has been developed to meet the clinical need. This review is intended to shed light on new understanding of the molecular pharmacology of opioids, which has arisen largely due to the genomic revolution, and what new drugs may become available in the coming years. Atypical opioids have and are being developed which not only target the mu opioid receptor but other targets in the pain pathway. Biased mu agonists have been developed but remain 'unbiased' clinically. The contribution of drugs targeting non-mu opioid receptors either alone or as heterodimers shows potential promise but remains understudied. That gene splice variants of the mu opioid receptor produce multiple receptor isoforms in different brain regions, and may change with pain chronicity and phenotype, presents new challenges but also opportunities for precision pain medicine. Finally, that opioids also have pro-inflammatory effects not aligned with mu opioid receptor binding affinity implicates a fresh understanding of their role in chronic pain, whether cancer or non-cancer. Hopefully, a new understanding of opioid analgesic drug action may lead to new drug development and better precision medicine in acute and chronic pain relief with less patient harm.
Collapse
Affiliation(s)
- Andrew A Somogyi
- Discipline of Pharmacology, University of Adelaide, Adelaide, Australia
| | - Stefan T Musolino
- Discipline of Pharmacology, University of Adelaide, Adelaide, Australia
| | - Daniel T Barratt
- Discipline of Physiology, University of Adelaide, Adelaide, Australia
| |
Collapse
|
12
|
Reid C, Beynon C, Kennedy E, O'Farrelly C, Meade KG. Bovine innate immune phenotyping via a standardized whole blood stimulation assay. Sci Rep 2021; 11:17227. [PMID: 34446770 PMCID: PMC8390753 DOI: 10.1038/s41598-021-96493-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 08/04/2021] [Indexed: 12/24/2022] Open
Abstract
Cattle vary in their susceptibility to infection and immunopathology, but our ability to measure and longitudinally profile immune response variation is limited by the lack of standardized immune phenotyping assays for high-throughput analysis. Here we report longitudinal innate immune response profiles in cattle using a low-blood volume, whole blood stimulation system—the ImmunoChek (IChek) assay. By minimizing cell manipulation, our standardized system minimizes the potential for artefactual results and enables repeatable temporal comparative analysis in cattle. IChek successfully captured biological variation in innate cytokine (IL-1β and IL-6) and chemokine (IL-8) responses to 24-hr stimulation with either Gram-negative (LPS), Gram-positive (PamCSK4) bacterial or viral (R848) pathogen-associated molecular patterns (PAMPs) across a 4-month time window. Significant and repeatable patterns of inter-individual variation in cytokine and chemokine responses, as well as consistent high innate immune responder individuals were identified at both baseline and induced levels. Correlation coefficients between immune response read-outs (IL-1β, IL-6 and IL-8) varied according to PAMP. Strong significant positive correlations were observed between circulating monocytes and IL-6 levels for null and induced responses (0.49–0.61) and between neutrophils and cytokine responses to R848 (0.38–0.47). The standardized assay facilitates high-throughput bovine innate immune response profiling to identify phenotypes associated with disease susceptibility and responses to vaccination.
Collapse
Affiliation(s)
- Cian Reid
- Animal and Bioscience Research Department, Animal & Grassland Research and Innovation Centre, Teagasc, Grange, Co Meath, Ireland.,School of Biochemistry and Immunology, Trinity College Dublin, Dublin 2, Ireland
| | - Charlotte Beynon
- Animal and Bioscience Research Department, Animal & Grassland Research and Innovation Centre, Teagasc, Grange, Co Meath, Ireland.,School of Biochemistry and Immunology, Trinity College Dublin, Dublin 2, Ireland
| | - Emer Kennedy
- Teagasc, Animal & Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland
| | - Cliona O'Farrelly
- School of Biochemistry and Immunology, Trinity College Dublin, Dublin 2, Ireland.,School of Medicine, Trinity College Dublin, Dublin 2, Ireland
| | - Kieran G Meade
- School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland. .,Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland. .,Institute of Food and Health, University College Dublin, Belfield, Dublin 4, Ireland.
| |
Collapse
|
13
|
Malafoglia V, Ilari S, Vitiello L, Tenti M, Balzani E, Muscoli C, Raffaeli W, Bonci A. The Interplay between Chronic Pain, Opioids, and the Immune System. Neuroscientist 2021; 28:613-627. [PMID: 34269117 DOI: 10.1177/10738584211030493] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chronic pain represents one of the most serious worldwide medical problems, in terms of both social and economic costs, often causing severe and intractable physical and psychological suffering. The lack of biological markers for pain, which could assist in forming clearer diagnoses and prognoses, makes chronic pain therapy particularly arduous and sometimes harmful. Opioids are used worldwide to treat chronic pain conditions, but there is still an ambiguous and inadequate understanding about their therapeutic use, mostly because of their dual effect in acutely reducing pain and inducing, at the same time, tolerance, dependence, and a risk for opioid use disorder. In addition, clinical studies suggest that opioid treatment can be associated with a high risk of immune suppression and the development of inflammatory events, worsening the chronic pain status itself. While opioid peptides and receptors are expressed in both central and peripheral nervous cells, immune cells, and tissues, the role of opioids and their receptors, when and why they are activated endogenously and what their exact role is in chronic pain pathways is still poorly understood. Thus, in this review we aim to highlight the interplay between pain and immune system, focusing on opioids and their receptors.
Collapse
Affiliation(s)
| | - Sara Ilari
- Department of Health Science Institute of Research for Food Safety & Health (IRC-FSH), University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | | | - Michael Tenti
- Institute for Research on Pain, ISAL Foundation, Rimini, Italy
| | - Eleonora Balzani
- Department of Surgical Science, University of Turin, Turin, Italy
| | - Carolina Muscoli
- Department of Health Science Institute of Research for Food Safety & Health (IRC-FSH), University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | | | | |
Collapse
|
14
|
Evans SF, Kwok Y, Solterbeck A, Pyragius C, Hull ML, Hutchinson MR, Rolan P. The Relationship Between Androgens and Days per Month of Period Pain, Pelvic Pain, Headache, and TLR4 Responsiveness of Peripheral Blood Mononuclear Cells in Young Women with Dysmenorrhoea. J Pain Res 2021; 14:585-599. [PMID: 33688248 PMCID: PMC7937378 DOI: 10.2147/jpr.s279253] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Accepted: 01/07/2021] [Indexed: 01/10/2023] Open
Abstract
Purpose Women bear a disproportionate burden of persistent pain conditions when compared to men. To determine whether the hormonal environment affects the clinical experience of pain, as measured by the days per month of pelvic pain (DPelvicPM), period pain (DPeriodPM), headache (DHeadachePM) or the in vitro EC50 for Interleukin-1β (IL-1β) release following TLR4 stimulation with Lipopolysaccharide from Peripheral Blood Mononuclear Cells (PBMCs). Findings were stratified according to use or non-use of the oral contraceptive pill. Patients and Methods Fifty-six women aged 16–35 years, with minimal or severe dysmenorrhea, and use or non-use of the OC, were enrolled. Blood was collected on two occasions in a single menstrual cycle: Days 1–2 and Days 7–10. Hormonal analysis for testosterone, dihydrotestosterone, dehydroepiandrosterone, Androstenedione, 3α-Androstanediol, 3β-androstanediol, estradiol, estrone, 17α-hydroxyprogesterone, progesterone, cortisol and sex-hormone binding globulin was undertaken using ultra-sensitive Liquid Chromatography Mass–Spectrometry (LC-MS). PBMCs were exposed to lipopolysaccharide (LPS) and the resulting Interleukin-1β output was determined. Results Non-users of the OC showed a strongly inverse correlation between a reducing free androgen index (FAI) and increasing DPelvicPM (p=0.0032), DPeriodPM (p=0.013), DHeadachePM (p=0.041). Non-users of the OC showed a significant increase in DPelvicPM (p=0.049) on Days 7–10. Modestly significant associations were found between reduced androgens and potentiated LPS-induced IL-1β (lower EC50). Conclusion This is the first study to investigate the relationship between the hormonal environment and activation of the immune system in young women with dysmenorrhoea-related pain conditions. Low androgen levels were consistently associated with increased pain. Translational implications for the findings are discussed.
Collapse
Affiliation(s)
- Susan F Evans
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
| | - Yuen Kwok
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
| | | | - Carmen Pyragius
- School of Paediatrics & Reproductive Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Mary Louise Hull
- Robinson Research Institute, School of Pediatrics and Reproductive Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Mark R Hutchinson
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia.,ARC Centre of Excellence for Nanoscale Biophotonics, University of Adelaide, Adelaide, South Australia, Australia
| | - Paul Rolan
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
| |
Collapse
|
15
|
The Neuroimmunology of Chronic Pain: From Rodents to Humans. J Neurosci 2020; 41:855-865. [PMID: 33239404 DOI: 10.1523/jneurosci.1650-20.2020] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/29/2020] [Accepted: 10/04/2020] [Indexed: 12/11/2022] Open
Abstract
Chronic pain, encompassing conditions, such as low back pain, arthritis, persistent post-surgical pain, fibromyalgia, and neuropathic pain disorders, is highly prevalent but remains poorly treated. The vast majority of therapeutics are directed solely at neurons, despite the fact that signaling between immune cells, glia, and neurons is now recognized as indispensable for the initiation and maintenance of chronic pain. This review highlights recent advances in understanding fundamental neuroimmune signaling mechanisms and novel therapeutic targets in rodent models of chronic pain. We further discuss new technological developments to study, diagnose, and quantify neuroimmune contributions to chronic pain in patient populations.
Collapse
|
16
|
Møller Johansen L, Gerra MC, Arendt-Nielsen L. Time course of DNA methylation in pain conditions: From experimental models to humans. Eur J Pain 2020; 25:296-312. [PMID: 33063322 DOI: 10.1002/ejp.1674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND OBJECTIVE Throughout the last decade, research has uncovered associations between pain and epigenetic alterations caused by environmental factors. Specifically, studies have demonstrated correlations between pain conditions and altered DNA methylation patterns. Thus, DNA methylation has been revealed as a possible modulator or contributor to pain conditions, providing a potential therapeutic target for treatment by DNA methylation modification. To develop such treatments, it is necessary to clarify a wide number of aspects on how DNA methylation affects pain perception; first and foremost, the temporal dynamics. The objective of the present review is to provide an overview of current knowledge on temporal dynamics of DNA methylation in response to pain, and to investigate if a timeframe can be established based on the data of currently published studies. DATABASES AND DATA TREATMENT PubMed, MEDLINE, Google Scholar and Embase were searched comprehensively for studies of DNA methylation in neuropathic, inflammatory and alternative animal pain models, and in chronic pain patients including Complex Regional Pain Syndrome, chronic postsurgical pain, chronic widespread pain, fibromyalgia and Crohn's disease. RESULTS We identified 34 articles highlighting variations in temporal dynamics of DNA methylation across species and between different types of pain. These studies represent a starting point to uncover new insights in the DNA methylation time course in pain. CONCLUSIONS No timeframe can currently be made for the DNA methylation response to pain in any of the reviewed conditions, highlighting an important focus area for future research.
Collapse
Affiliation(s)
- Lonnie Møller Johansen
- Department of Health Science and Technology, The Faculty of Medicine, Aalborg University, Aalborg, Denmark
| | - Maria Carla Gerra
- Center for Neuroplasticity and Pain (CNAP), SMI®, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Lars Arendt-Nielsen
- Center for Neuroplasticity and Pain (CNAP), SMI®, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| |
Collapse
|
17
|
Evans SF, Kwok YH, Solterbeck A, Liu J, Hutchinson MR, Hull ML, Rolan PE. Toll-Like Receptor Responsiveness of Peripheral Blood Mononuclear Cells in Young Women with Dysmenorrhea. J Pain Res 2020; 13:503-516. [PMID: 32210607 PMCID: PMC7071941 DOI: 10.2147/jpr.s219684] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Accepted: 01/20/2020] [Indexed: 12/13/2022] Open
Abstract
PURPOSE Dysmenorrhea is a common disorder that substantially disrupts the lives of young women. To determine whether there is evidence of activation of the innate immune system in dysmenorrhea and whether the degree of activation may be used as a biomarker for pain, we compared the responsiveness of peripheral blood mononuclear cells (PBMCs) to toll-like receptor (TLR) 2 or 4 stimulation. We also investigated whether this effect is modulated by the use of the oral contraceptive pill (OC). PATIENTS AND METHODS Fifty-six women aged 16-35 years, with either severe or minimal dysmenorrhea, and use or non-use of the OC, were enrolled. PBMCs were collected on two occasions in a single menstrual cycle: the menstrual phase and the mid-follicular phase. PBMCs were exposed to lipopolysaccharide (LPS), a TLR4 agonist, and PAM3CSK4 (PAM), a TLR2 agonist, and the resulting interleukin-1beta (IL-1β) output was determined. Statistical analysis compared the EC50 between groups as a measure of TLR responsiveness of PBMCs. RESULTS The key finding following LPS stimulation was a pain effect of dysmenorrhea (p=0.042) that was independent of use or non-use of OC, and independent of day of testing. Women with dysmenorrhea showed a large 2.15-fold (95% CI -4.69, -0.09) increase in IL-1β release when compared with pain-free participants across both days. CONCLUSION This is the first study to demonstrate an ex vivo immune relationship in women with dysmenorrhea-related pelvic pain. It provides evidence for the potential of immune modulation as a novel pharmacological target for future drug development in the management of dysmenorrhea.
Collapse
Affiliation(s)
- Susan F Evans
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
| | - Yuen H Kwok
- Faculty of Health Science, University of Adelaide, Adelaide, South Australia, Australia
| | | | - Jiajun Liu
- Faculty of Health Science, University of Adelaide, Adelaide, South Australia, Australia
| | - Mark R Hutchinson
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, University of Adelaide, Adelaide, South Australia, Australia
| | - M Louise Hull
- Robinson Research Institute, School or Pediatrics and Reproductive Health, University of Adelaide, Adelaide, South Australia, Australia
| | - Paul E Rolan
- School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
| |
Collapse
|
18
|
Diasso PDK, Birke H, Nielsen SD, Main KM, Højsted J, Sjøgren P, Kurita GP. The effects of long-term opioid treatment on the immune system in chronic non-cancer pain patients: A systematic review. Eur J Pain 2019; 24:481-496. [PMID: 31705699 DOI: 10.1002/ejp.1506] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 11/05/2019] [Accepted: 11/07/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND OBJECTIVE Opioids have been increasingly prescribed for chronic non-cancer pain (CNCP). An association between long-term opioid treatment (L-TOT) of CNCP patients and suppression of both the innate and the adaptive immune system has been proposed. This systematic review aims at investigating the effects of L-TOT on the immune system in CNCP patients. DATABASES AND DATA TREATMENT A systematic search of MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and the CINAHL for relevant articles was performed. Studies examining measures of both the innate and the adaptive immune system in adult CNCP patients in L-TOT (≥4 weeks of intake) were included. Outcomes and the level of evidence were analysed. RESULTS A total of 382 studies were identified; however, 376 were excluded (352 inappropriate methodology, 21 duplicates, three full-text could not be obtained) and one randomized controlled trial (RCT) and five cross-sectional studies were included and analysed. L-TOT compared with no treatment was associated with a lower percentage of natural killer (NK) cells, a lower absolute number of CD56bright NK cells, a higher absolute number of IL-2-activated NK cells and a higher concentration of IL-1β as a response to toll-like receptor (TLR) agonists stimulation (Pam3CSK4, LPS, Imiquimod). No other significant differences were reported. Generalizability of the results was limited due to inconsistency of outcomes and an overall low quality of the studies. CONCLUSIONS L-TOT may alter the immune system in CNCP patients, but the level of evidence is still weak. More studies are needed to clarify the impact of L-TOT on immune system function. SIGNIFICANCE This systematic review found indication that long-term opioid treatment alters the immune system in chronic non-cancer pain patients. These alterations involved the NK cells and IL-1β production. However, the level of evidence is weak.
Collapse
Affiliation(s)
- Pernille D K Diasso
- Department of Oncology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Hanne Birke
- Department of Clinical Research and Prevention, Frederiksberg Hospital, Frederiksberg, Denmark
| | - Susanne D Nielsen
- Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Katharina M Main
- Department of Growth and Reproduction and EDMaRC, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Jette Højsted
- Multidisciplinary Pain Centre, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Per Sjøgren
- Department of Oncology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.,Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Geana P Kurita
- Department of Oncology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.,Multidisciplinary Pain Centre, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| |
Collapse
|
19
|
Teodorczyk-Injeyan JA, Triano JJ, Injeyan HS. Nonspecific Low Back Pain: Inflammatory Profiles of Patients With Acute and Chronic Pain. Clin J Pain 2019; 35:818-825. [PMID: 31283548 PMCID: PMC6735949 DOI: 10.1097/ajp.0000000000000745] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 05/15/2019] [Accepted: 06/14/2019] [Indexed: 12/14/2022]
Abstract
BACKGROUND The pathogenesis of low back pain (LBP) remains unclear. However, recent studies suggest that the inflammatory response may be inherent in spinal pain. The purpose of this study was to discern inflammatory profiles in patients with nonspecific acute and chronic LBP in relation to those in asymptomatic individuals. MATERIALS AND METHODS Peripheral blood samples were obtained from asymptomatic controls and patients with nonspecific acute and chronic LBP reporting a minimum pain score of 3 on a 10-point Visual Analogue Scale (VAS). The levels of in vitro production of proinflammatory (tumor necrosis factor α [TNFα], interleukin [IL] 1β, IL-6, IL-2, interferon γ) and anti-inflammatory (IL-1 receptor antagonist, soluble receptors of TNF2, and IL-10) mediators were determined by specific immunoassays. RESULTS The mean VAS scores were comparable between the acute and chronic LBP patient groups. Compared with asymptomatic group, the production of TNFα, IL-1β, IL-6 and their ratios to IL-10 levels were significantly elevated in both patient groups (P=0.0001 to 0.003). In acute LBP group, the ratio of IL-2:IL-10 was also significantly increased (P=0.02). In contrast, the production of interferon γ was significantly reduced compared with the other study groups (P=0.005 to 0.01), nevertheless, it was positively correlated (P=0.006) with pain scores. In chronic LBP patients, the production of TNFα, IL-1 receptor antagonist, and soluble receptors of TNF2 was significantly increased (P=0.001 to 0.03) in comparison with the control and acute LBP groups, and TNFα and IL-1β levels were positively correlated (P<0.001) with VAS scores. CONCLUSIONS The inflammatory profiles of patients with acute and chronic LBP are distinct. Nonetheless, in both patient groups, an imbalance between proinflammatory and anti-inflammatory mediator levels favors the production of proinflammatory components.
Collapse
Affiliation(s)
| | | | - H. Stephen Injeyan
- Research and Clinical Education Programs, Canadian Memorial Chiropractic College, Toronto, ON, Canada
| |
Collapse
|
20
|
Review: What innovations in pain measurement and control might be possible if we could quantify the neuroimmune synapse? Animal 2019; 13:3000-3008. [PMID: 31405403 DOI: 10.1017/s1751731119001885] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
It has taken more than 40 years for the fields of immunology and neuroscience to capture the potential impact of the mechanistic understanding of how an active immune signalling brain might function. These developments have grown an appreciation for the immunocompetent cells of the central nervous system and their key role in the health and disease of the brain and spinal cord. Moreover, the understanding of the bidirectional communication between the brain and the peripheral immune system has evolved to capture an understanding of how mood can alter immune function and vice versa. These concepts are rapidly evolving the field of psychiatry and medicine as a whole. However, the advances in human medicine have not been capitalised upon yet in animal husbandry practice. Of specific attention are the implications that these biological systems have for creating and maintaining heightened pain states. This review will outline the key concepts of brain-immune communication and the immediate opportunities targeting this biology can have for husbandry practices, with a specific focus on pain.
Collapse
|
21
|
Kaliyaperumal S, Wilson K, Aeffner F, Dean C. Animal Models of Peripheral Pain: Biology Review and Application for Drug Discovery. Toxicol Pathol 2019; 48:202-219. [PMID: 31269874 DOI: 10.1177/0192623319857051] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Pain is a complex constellation of cognitive, unpleasant sensory, and emotional experiences that primarily serves as a survival mechanism. Pain arises in the peripheral nervous system and pain signals synapse with nerve tracts extending into the central nervous system. Several different schemes are used to classify pain, including the underlying mechanism, tissues primarily affected, and time-course. Numerous animal models of pain, which should be employed with appropriate Institutional Animal Care and Use approvals, have been developed to elucidate pathophysiology mechanisms and aid in identification of novel therapeutic targets. The variety of available models underscores the observations that pain phenotypes are driven by several distinct mechanisms. Pain outcome measurement encompasses both reflexive (responses to heat, cold, mechanical and electrical stimuli) and nonreflexive (spontaneous pain responses to stimuli) behaviors. However, the question of translatability to human pain conditions and potential treatment outcomes remains a topic of continued scrutiny. In this review we discuss the different types of pain and their mechanisms and pathways, available rodent pain models with an emphasis on type of pain stimulations and pain outcome measures and discuss the role of pathologists in assessing and validating pain models.
Collapse
Affiliation(s)
| | | | | | - Charles Dean
- Amgen, Inc, Thousand Oaks, CA, USA *Both authors equally contributed to the manuscript
| |
Collapse
|
22
|
Abstract
One of the fundamental mechanisms whereby the innate immune system coordinates inflammatory signal transduction is through Toll-like receptors (TLRs), which function to protect and defend the host organism by initiating inflammatory signaling cascades in response to tissue damage or injury. TLRs are positioned at the neuroimmune interface, and accumulating evidence suggests that the inflammatory consequences of TLR activation on glia (including microglia and astrocytes), sensory neurons, and other cell types can influence nociceptive processing and lead to states of exaggerated and unresolved pain. In this review, we summarize our current understanding of how different TLRs and their accessory or adaptor molecules can contribute to the development and maintenance of persistent pain. The challenges and opportunities of targeting TLRs for new treatment strategies against chronic pain are discussed, including the therapeutic context of TLR-mediated signaling in opioid analgesia and chemotherapy-induced pain. Considering the prevalence of persistent pain and the insufficient efficacy and safety of current treatment options, a deeper understanding of Toll-like receptors holds the promise of novel therapies for managing pathological pain.
Collapse
|
23
|
Biological Stress Systems, Adverse Life Events, and the Improvement of Chronic Multisite Musculoskeletal Pain Across a 6-Year Follow-Up. THE JOURNAL OF PAIN 2017; 18:155-165. [DOI: 10.1016/j.jpain.2016.10.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 10/11/2016] [Accepted: 10/14/2016] [Indexed: 01/01/2023]
|
24
|
Guerrero ATG, Pinto LG, Cunha FQ, Ferreira SH, Alves-Filho JC, Verri WA, Cunha TM. Mechanisms underlying the hyperalgesic responses triggered by joint activation of TLR4. Pharmacol Rep 2016; 68:1293-1300. [PMID: 27689757 DOI: 10.1016/j.pharep.2016.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 08/15/2016] [Accepted: 08/23/2016] [Indexed: 01/04/2023]
Abstract
BACKGROUND Toll-like receptors (TLRs) including TLR4 and their signal pathways contribute to the pathogenesis of arthritis. Herein, we evaluated the mechanisms underlying the hyperalgesic response caused by TLR4 activation in the tibio-tarsal joint in mice. METHODS Joint inflammatory hyperalgesia was induced by intra-articular (ia) injection of LPS (lipopolysaccharide- TLR4 agonist) in C57BL/6, TLR4, TLR2, MyD88, TRIF, TNFR1/2 and IL-1R1 knockout (-/-) mice. Joint hyperalgesia was evaluated using an electronic von Frey. Neutrophil recruitment was assessed by MPO activity. Joint levels of cytokines were measured by ELISA. RESULTS Firstly, it was shown that LPS injected into the joints causes a dose- and time-dependent reduction in the mechanical nociceptive threshold. The TLR4 activation in the joint triggers mechanical hyperalgesia and neutrophil migration, which was abolished in TLR4 -/- and MyD88-/-, but not in TLR2-/- and TRIF-/- mice. Besides, joint administration of LPS increased the release of TNF-α, IL-1β, and KC/CXCL1, which were reduced in TLR4-/- and MyD88-/-, but not in TRIF-/- mice. In agreement, the LPS-induced joint nociceptive effect was decreased in TNFR1/2-/- and IL-1R1-/- mice or in mice pre-treated with a CXCR1/2 selective antagonist (DF2156A). CONCLUSIONS These results suggest that TLR4 activation in the joint produces articular hyperalgesia via MyD88 signaling pathway. Moreover, this pathway is involved in the cascade of events of articular hyperalgesia through mechanisms dependent on cytokines and chemokines production. Thus, TLR4/MyD88 signaling pathway inhibitors might be useful for the treatment of inflammatory joint pain.
Collapse
Affiliation(s)
- Ana T G Guerrero
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Avenida Bandeirantes, 3900, 14049-900 Ribeirão Preto, São Paulo, Brazil; Fundação Oswaldo Cruz-FIOCRUZ Mato Grosso do Sul, Rua Gabriel Abrão 92, 79081-746 Campo Grande, Mato Grosso do Sul, Brazil.
| | - Larissa G Pinto
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Avenida Bandeirantes, 3900, 14049-900 Ribeirão Preto, São Paulo, Brazil.
| | - Fernando Q Cunha
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Avenida Bandeirantes, 3900, 14049-900 Ribeirão Preto, São Paulo, Brazil.
| | - Sérgio H Ferreira
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Avenida Bandeirantes, 3900, 14049-900 Ribeirão Preto, São Paulo, Brazil.
| | - Jose C Alves-Filho
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Avenida Bandeirantes, 3900, 14049-900 Ribeirão Preto, São Paulo, Brazil.
| | - Waldiceu A Verri
- Departamento de Patologia, Centro de Ciências Biológicas, Universidade Estadual de Londrina, Paraná, Rod. Celso Garcia Cid Km380 PR445, 86057-970 Londrina, Paraná, Brazil.
| | - Thiago M Cunha
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Avenida Bandeirantes, 3900, 14049-900 Ribeirão Preto, São Paulo, Brazil.
| |
Collapse
|
25
|
Gaurilcikaite E, Renton T, Grant AD. The paradox of painless periodontal disease. Oral Dis 2016; 23:451-463. [PMID: 27397640 DOI: 10.1111/odi.12537] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 05/04/2016] [Accepted: 06/23/2016] [Indexed: 12/23/2022]
Abstract
Periodontal diseases, primarily gingivitis and periodontitis, are characterised by progressive inflammation and tissue destruction. However, they are unusual in that they are not also accompanied by the pain commonly seen in other inflammatory conditions. This suggests that interactions between periodontal bacteria and host cells create a unique environment in which the pro-algesic effects of inflammatory mediators and factors released during tissue damage are directly or indirectly inhibited. In this review, we summarise the evidence that periodontal disease is characterised by an accumulation of classically pro-algesic factors from bacteria and host cells. We then discuss several mechanisms by which inflammatory sensitisation of nociceptive fibres could be prevented through inactivation or inhibition of these factors. Further studies are necessary to fully understand the molecular processes underlying the endogenous localised hypoalgesia in human periodontal disease. This knowledge might provide a rational basis to develop future therapeutic interventions, such as host modulation therapies, against a wide variety of other human pain conditions.
Collapse
Affiliation(s)
- E Gaurilcikaite
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - T Renton
- Department of Oral Surgery, Dental Institute, King's College London, London, UK
| | - A D Grant
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| |
Collapse
|
26
|
Helley M, Abate W, Jackson S, Bennett J, Thompson S. The expression of Toll-like receptor 4, 7 and co-receptors in neurochemical sub-populations of rat trigeminal ganglion sensory neurons. Neuroscience 2015; 310:686-98. [DOI: 10.1016/j.neuroscience.2015.09.069] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 09/03/2015] [Accepted: 09/25/2015] [Indexed: 12/12/2022]
|
27
|
Cruz-Almeida Y, Aguirre M, Sorenson HL, Tighe P, Wallet SM, Riley JL. Age differences in cytokine expression under conditions of health using experimental pain models. Exp Gerontol 2015; 72:150-6. [PMID: 26456458 DOI: 10.1016/j.exger.2015.09.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 09/23/2015] [Accepted: 09/25/2015] [Indexed: 11/20/2022]
Abstract
Older adults are at an increased risk to develop frequent and prolonged pain. Emerging evidence proposes a link between immune changes and pain, which is consistent with the inflammation theory of aging and the increased incidence of age-related diseases. This study tested the hypothesis that older adults show greater immune responses to experimental pain compared to younger individuals. Study subjects (8 younger and 9 older healthy adults) underwent 3 experimental sessions using well-validated human experimental pain models: the cold pressor task (CPT), focal heat pain (FHP), and a non-painful thermal control. Blood was collected through an indwelling catheter at baseline and 3, 15, 30, 45, 60, and 90 min post-stimuli administration. Pro-inflammatory cytokines (TNF-α IL-6 and IL-8) peaked at the same time points for both groups, with greater elevations among older subjects for TNF-α and IL-8 in both pain models and elevations in IL-6 only for CPT. Anti-inflammatory cytokines (IL-4, IL-5, and IL-10) generally peaked later for the older subjects, with increased elevations for FHP but not the CPT. These data are consistent with the assertion that age-related immune system dysregulation may account for the increased prevalence of pain in older adults.
Collapse
Affiliation(s)
- Yenisel Cruz-Almeida
- Pain Research & Intervention Center of Excellence (PRICE), United States; Institute of Aging, College of Medicine, United States; Department of Community Dentistry and Behavioral Science, College of Dentistry, United States
| | - Maria Aguirre
- Pain Research & Intervention Center of Excellence (PRICE), United States; Department of Community Dentistry and Behavioral Science, College of Dentistry, United States
| | | | - Patrick Tighe
- Pain Research & Intervention Center of Excellence (PRICE), United States; Department of Anesthesiology, College of Medicine, United States
| | | | - Joseph L Riley
- Pain Research & Intervention Center of Excellence (PRICE), United States; Department of Community Dentistry and Behavioral Science, College of Dentistry, United States
| |
Collapse
|
28
|
Schrepf A, Bradley CS, O'Donnell M, Luo Y, Harte SE, Kreder K, Lutgendorf S. Toll-like receptor 4 and comorbid pain in Interstitial Cystitis/Bladder Pain Syndrome: a multidisciplinary approach to the study of chronic pelvic pain research network study. Brain Behav Immun 2015; 49:66-74. [PMID: 25771510 PMCID: PMC4567436 DOI: 10.1016/j.bbi.2015.03.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 03/03/2015] [Accepted: 03/04/2015] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS) is a condition characterized by pelvic pain and urinary symptoms. Some IC/BPS patients have pain confined to the pelvic region, while others suffer widespread pain. Inflammatory processes have previously been linked to pelvic pain in IC/BPS, but their association with widespread pain in IC/BPS has not been characterized. METHODS Sixty-six women meeting criteria for IC/BPS completed self-report measures of pain as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP), collected 3days of saliva for cortisol assays, and provided blood samples. Peripheral blood mononuclear cells (PBMCs) were stimulated with Toll-like Receptor (TLR) 2 and 4 agonists and cytokines were measured in supernatant; IL-6 was also measured in plasma. Associations between inflammatory variables and the likelihood of endorsing extra-pelvic pain, or the presence of a comorbid syndrome, were tested by logistic regression and General Linear Models, respectively. A subset of patients (n=32) completed Quantitative Sensory Testing. RESULTS A one standard deviation increase in TLR-4 inflammatory response was associated with a 1.59 greater likelihood of endorsing extra-pelvic pain (p=.019). Participants with comorbid syndromes also had higher inflammatory responses to TLR-4 stimulation in PBMCs (p=.016). Lower pressure pain thresholds were marginally associated with higher TLR-4 inflammatory responses (p=.062), and significantly associated with higher IL-6 in plasma (p=.031). CONCLUSIONS TLR-4 inflammatory responses in PBMCs are a marker of widespread pain in IC/BPS, and should be explored in other conditions characterized by medically unexplained pain.
Collapse
Affiliation(s)
- Andrew Schrepf
- Department of Psychology, University of Iowa, United States
| | - Catherine S Bradley
- Department of Urology, University of Iowa, United States; Department of Obstetrics and Gynecology, University of Iowa, United States
| | | | - Yi Luo
- Department of Urology, University of Iowa, United States
| | - Steven E Harte
- Departments of Anesthesiology and Internal Medicine-Rheumatology, University of Michigan, United States
| | - Karl Kreder
- Department of Urology, University of Iowa, United States; Department of Obstetrics and Gynecology, University of Iowa, United States
| | - Susan Lutgendorf
- Department of Psychology, University of Iowa, United States; Department of Urology, University of Iowa, United States; Department of Obstetrics and Gynecology, University of Iowa, United States.
| |
Collapse
|
29
|
Johnson JL, Kwok YH, Sumracki NM, Swift JE, Hutchinson MR, Johnson K, Williams DB, Tuke J, Rolan PE. Glial Attenuation With Ibudilast in the Treatment of Medication Overuse Headache: A Double-Blind, Randomized, Placebo-Controlled Pilot Trial of Efficacy and Safety. Headache 2015; 55:1192-208. [DOI: 10.1111/head.12655] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/26/2015] [Indexed: 01/08/2023]
Affiliation(s)
| | - Yuen H. Kwok
- Discipline of Pharmacology, University of Adelaide; Adelaide Australia
| | | | - James E. Swift
- Discipline of Pharmacology, University of Adelaide; Adelaide Australia
| | | | | | - Desmond B. Williams
- School of Pharmacy and Medical Sciences; University of South Australia; Adelaide Australia
| | - Jonathon Tuke
- School of Mathematical Sciences; University of Adelaide; Adelaide Australia
| | - Paul E. Rolan
- Discipline of Pharmacology, University of Adelaide; Adelaide Australia
- Pain and Anaesthesia Research Clinic, Royal Adelaide Hospital; Adelaide Australia
- Pain Management Unit, Royal Adelaide Hospital; Adelaide Australia
| |
Collapse
|
30
|
Luo J, Feng J, Liu S, Walters ET, Hu H. Molecular and cellular mechanisms that initiate pain and itch. Cell Mol Life Sci 2015; 72:3201-23. [PMID: 25894692 PMCID: PMC4534341 DOI: 10.1007/s00018-015-1904-4] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 03/20/2015] [Accepted: 04/07/2015] [Indexed: 12/17/2022]
Abstract
Somatosensory neurons mediate our sense of touch. They are critically involved in transducing pain and itch sensations under physiological and pathological conditions, along with other skin-resident cells. Tissue damage and inflammation can produce a localized or systemic sensitization of our senses of pain and itch, which can facilitate our detection of threats in the environment. Although acute pain and itch protect us from further damage, persistent pain and itch are debilitating. Recent exciting discoveries have significantly advanced our knowledge of the roles of membrane-bound G protein-coupled receptors and ion channels in the encoding of information leading to pain and itch sensations. This review focuses on molecular and cellular events that are important in early stages of the biological processing that culminates in our senses of pain and itch.
Collapse
Affiliation(s)
- Jialie Luo
- Department of Anesthesiology, The Center for the Study of Itch, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, MO, 63110, USA
| | | | | | | | | |
Collapse
|
31
|
Evidence for a distinct neuro-immune signature in rats that develop behavioural disability after nerve injury. J Neuroinflammation 2015; 12:96. [PMID: 25986444 PMCID: PMC4506439 DOI: 10.1186/s12974-015-0318-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 05/05/2015] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Chronic neuropathic pain is a neuro-immune disorder, characterised by allodynia, hyperalgesia and spontaneous pain, as well as debilitating affective-motivational disturbances (e.g., reduced social interactions, sleep-wake cycle disruption, anhedonia, and depression). The role of the immune system in altered sensation following nerve injury is well documented. However, its role in the development of affective-motivational disturbances remains largely unknown. Here, we aimed to characterise changes in the immune response at peripheral and spinal sites in a rat model of neuropathic pain and disability. METHODS Sixty-two rats underwent sciatic nerve chronic constriction injury (CCI) and were characterised as either Pain and disability, Pain and transient disability or Pain alone on the basis of sensory threshold testing and changes in post-CCI dominance behaviour in resident-intruder interactions. Nerve ultrastructure was assessed and the number of T lymphocytes and macrophages were quantified at the site of injury on day six post-CCI. ATF3 expression was quantified in the dorsal root ganglia (DRG). Using a multiplex assay, eight cytokines were quantified in the sciatic nerve, DRG and spinal cord. RESULTS All CCI rats displayed equal levels of mechanical allodynia, structural nerve damage, and reorganisation. All CCI rats had significant infiltration of macrophages and T lymphocytes to both the injury site and the DRG. Pain and disability rats had significantly greater numbers of T lymphocytes. CCI increased IL-6 and MCP-1 in the sciatic nerve. Examination of disability subgroups revealed increases in IL-6 and MCP-1 were restricted to Pain and disability rats. Conversely, CCI led to a decrease in IL-17, which was restricted to Pain and transient disability and Pain alone rats. CCI significantly increased IL-6 and MCP-1 in the DRG, with IL-6 restricted to Pain and disability rats. CCI rats had increased IL-1β, IL-6 and MCP-1 in the spinal cord. Amongst subgroups, only Pain and disability rats had increased IL-1β. CONCLUSIONS This study has defined individual differences in the immune response at peripheral and spinal sites following CCI in rats. These changes correlated with the degree of disability. Our data suggest that individual immune signatures play a significant role in the different behavioural trajectories following nerve injury, and in some cases may lead to persistent affective-motivational disturbances.
Collapse
|
32
|
Generaal E, Vogelzangs N, Macfarlane GJ, Geenen R, Smit JH, de Geus EJCN, Penninx BWJH, Dekker J. Biological stress systems, adverse life events and the onset of chronic multisite musculoskeletal pain: a 6-year cohort study. Ann Rheum Dis 2015; 75:847-54. [DOI: 10.1136/annrheumdis-2014-206741] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 04/05/2015] [Indexed: 11/03/2022]
|
33
|
Grace PM, Maier SF, Watkins LR. Opioid-induced central immune signaling: implications for opioid analgesia. Headache 2015; 55:475-89. [PMID: 25833219 DOI: 10.1111/head.12552] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/20/2015] [Indexed: 12/30/2022]
Abstract
Despite being the mainstay of pain management, opioids are limited in their clinical utility by adverse effects, such as tolerance and paradoxical hyperalgesia. Research of the past 15 years has extended beyond neurons, to implicate central nervous system immune signaling in these adverse effects. This article will provide an overview of these central immune mechanisms in opioid tolerance and paradoxical hyperalgesia, including those mediated by Toll-like receptor 4, purinergic, ceramide, and chemokine signaling. Challenges for the future, as well as new lines of investigation will be highlighted.
Collapse
|
34
|
Cairns BE, Arendt-Nielsen L, Sacerdote P. Perspectives in Pain Research 2014: Neuroinflammation and glial cell activation: The cause of transition from acute to chronic pain? Scand J Pain 2015; 6:3-6. [DOI: 10.1016/j.sjpain.2014.10.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 09/22/2014] [Indexed: 11/25/2022]
Abstract
Abstract
Background
It is unknown why an acute pain condition under various circumstances can transition into a chronic pain condition.
There has been a shift towards neuroinflammation and hence glial cell activations specifically in the dorsal root ganglion and spinal cord as a mechanism possibly driving the transition to chronic pain. This has led to a focus on non-neuronal cells in the peripheral and central nervous system. Besides infiltrating macrophages, Schwann cells and satellite glial cells release cytokines and therefore important mechanisms in the maintenance of pain. Activated Schwann cells, satellite glial cells, microglia, and astrocytes may contribute to pain sensitivity by releasing cytokines leading to altered neuronal function in the direction of sensitisation.
Aims of this perspective paper
1) Highlight the complex but important recent achievement in the area of neuroinflammation and pain at spinal cord level and in the dorsal root ganglion.
2) Encourage further research which hopefully may provide better understanding of new key elements driving the transition from acute to chronic pain.
Recent results in the area of neuroinflammation and pain
Following a sciatic nerve injury, local macrophages, and Schwann cells trigger an immune response immediately followed by recruitment of blood-derived immune cells. Schwann cells, active resident, and infiltrating macrophages release proinflammatory cytokines. Proinflammatory cytokines contribute to axonal damage and also stimulate spontaneous nociceptor activity. This results in activation of satellite glial cells leading to an immune response in the dorsal root ganglia driven by macrophages, lymphocytes and satellite cells. The anterograde signalling progresses centrally to activate spinal microglia with possible up regulation of glial-derived proinflammatory/pronociceptive mediators.
An important aspect is extrasegmental spreading sensitisation where bilateral elevations in TNF-α, IL-6, and IL-10 are found in dorsal root ganglion in neuropathic models. Similarly in inflammatory pain models, bilateral up regulation occurs for TNF-α, IL-1 β, and p38 MAPK. Bilateral alterations in cytokine levels in the DRG and spinal cord may underlie the spread of pain to the uninjured side.
An important aspect is how the opioids may interact with immune cells as opioid receptors are expressed by peripheral immune cells and thus can induce immune signaling changes. Furthermore, opioids may stimulate microglia cells to produce proinflammatory cytokines such as IL-1.
Conclusions
The present perspective paper indicates that neuroinflammation and the associated release of pro-inflammatory cytokines in dorsal root ganglion and at the spinal cord contribute to the transition from acute to chronic pain. Neuroinflammatory changes have not only been identified in the spinal cord and brainstem, but more recently, in the sensory ganglia and in the nerves as well. The glial cell activation may be responsible for contralateral spreading and possible widespread sensitisation.
Implications
Communication between glia and neurons is proposed to be a critical component of neuroinflammatory changes that may lead to chronic pain. Sensory ganglia neurons are surrounded by satellite glial cells but how communication between the cells contributes to altered pain sensitivity is still unknown. Better understanding may lead to new possibilities for (1) preventing development of chronic pain and (2) better pain management.
Collapse
Affiliation(s)
- Brian E. Cairns
- Faculty of Pharmaceutical Sciences , University of British Columbia , 2405 Wesbrook Mall , Vancouver, BC , Canada V6T 1Z3
- Center for Sensory-Motor Interaction, Department of Health Science and Technology, Faculty of Medicine , Aalborg University, Frederik Bajers Vej 7D3, 9220 Aalborg East , Denmark
| | - Lars Arendt-Nielsen
- Center for Sensory-Motor Interaction, Department of Health Science and Technology, Faculty of Medicine , Aalborg University, Frederik Bajers Vej 7D3, 9220 Aalborg East , Denmark
| | - Paola Sacerdote
- Dipartimento di Scienze farmacologiche e biomolecolari , Università degli Studi di Milano , Via Vanvitelli 32, 20129 Milano , Italy
| |
Collapse
|
35
|
Sindberg GM, Sharma U, Banerjee S, Anand V, Dutta R, Gu CJ, Volsky DJ, Roy S. An infectious murine model for studying the systemic effects of opioids on early HIV pathogenesis in the gut. J Neuroimmune Pharmacol 2014; 10:74-87. [PMID: 25502600 DOI: 10.1007/s11481-014-9574-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 12/03/2014] [Indexed: 10/24/2022]
Abstract
Opioids are known to exacerbate HIV pathogenesis, however current studies have been limited by models of HIV infection. Given that HIV causes many systemic effects via direct infection of host cells as well as indirect bystander effects, it is important to establish a systemic infection model in a small animal so that genetic tools can be utilized to elucidate the mechanisms of action. In this study, the systemic effects of EcoHIV infection, a modified HIV which can infect mouse cells, are examined in conjunction with morphine. EcoHIV infection with opioid treatment induced bacterial translocation from the lumen of the gut into systemic compartments such as liver, which is similar to observations in human patients with LPS. Bacterial translocation corresponds with alterations in gut morphology, disorganization of the tight junction protein occludin, and a concurrent increase in systemic inflammation in both IL-6 and TNFα. Long term infection also had increased expression of inflammatory cytokines in the CNS when co-treated with morphine. Overall, this study shows that EcoHIV is an appropriate model to study the effects of opioids on HIV pathogenesis, including the HIV-induced pathology at early stages of pathogenesis in the gut.
Collapse
Affiliation(s)
- Gregory M Sindberg
- Department of Veterinary Population Medicine, University of Minnesota, 1988 Fitch Avenue Room 295, Saint Paul, MN, 55108, USA
| | | | | | | | | | | | | | | |
Collapse
|
36
|
Abstract
This paper is the thirty-sixth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2013 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.
Collapse
Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, United States.
| |
Collapse
|
37
|
Schrepf A, O'Donnell M, Luo Y, Bradley CS, Kreder K, Lutgendorf S. Inflammation and inflammatory control in interstitial cystitis/bladder pain syndrome: Associations with painful symptoms. Pain 2014; 155:1755-1761. [PMID: 24907404 DOI: 10.1016/j.pain.2014.05.029] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 05/19/2014] [Accepted: 05/29/2014] [Indexed: 10/25/2022]
Abstract
Toll-like receptors (TLR) are known to play a role in chronic pain, from animal models and limited research in humans, but their role in interstitial cystitis/bladder pain syndrome (IC/BPS) is unknown. Similarly, alterations of the hypothalamic-pituitary-adrenal axis have been reported in some pain conditions. Our objectives were to identify inflammatory processes that might distinguish individuals with IC/BPS from healthy controls (HC) and to examine their associations with IC/BPS symptoms. Female participants (58IC/BPS patients and 28HCs) completed pain and urinary symptom questionnaires and collected saliva for cortisol as part of the Multidisciplinary Approach to Pelvic Pain study. Inflammatory cytokines were assayed in plasma, and in TLR-2- and TLR-4-stimulated peripheral blood mononuclear cells. Controlling for BMI and negative affect, between-group differences were analyzed by general linear models, and relationships between symptoms and inflammatory variables were analyzed by regression. Compared to HCs, IC/BPS patients had higher levels of plasma interleukin-6 (P=.040), greater interleukin-1β responsive to TLR-2 stimulation (P=.040), and flatter diurnal cortisol slopes (P=.010), indicating inflammatory dysregulation. In IC/BPS patients, inflammation after TLR-4 stimulation was associated with multiple symptoms, including genitourinary pain (P=.010), sexual pain (P=.002), and marginally with urinary symptoms (P=.068). Genitourinary pain severity (P=.008), frequency (P=.001), and pain with intercourse (P=.002) were strongly associated with TLR-4 inflammatory response. TLR-4 appears to play a central role in painful symptoms of IC/BPS patients, which may be linked to poor endogenous inflammatory control. These findings may help to identify new mechanisms in IC/BPS and lead to new therapeutic approaches.
Collapse
Affiliation(s)
- Andrew Schrepf
- Department of Psychology, University of Iowa, Iowa City, IA, USA Department of Urology, University of Iowa, Ames, IA, USA Department of Obstetrics and Gynecology, University of Iowa, Iowa City, IA, USA
| | | | | | | | | | | | | |
Collapse
|
38
|
Generaal E, Vogelzangs N, Macfarlane GJ, Geenen R, Smit JH, Dekker J, Penninx BWJH. Basal inflammation and innate immune response in chronic multisite musculoskeletal pain. Pain 2014; 155:1605-1612. [PMID: 24813297 DOI: 10.1016/j.pain.2014.05.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 04/24/2014] [Accepted: 05/02/2014] [Indexed: 10/25/2022]
Abstract
Dysregulation of the immune system may play a role in chronic pain, although study findings are inconsistent. This cross-sectional study examined whether basal inflammatory markers and the innate immune response are associated with the presence and severity of chronic multisite musculoskeletal pain. Data were used on 1632 subjects of the Netherlands Study of Depression and Anxiety. The Chronic Pain Grade questionnaire was used to determine the presence and severity of chronic multisite musculoskeletal pain. Subjects were categorized in a chronic multisite musculoskeletal pain group (n=754) and a control group (n=878). Blood levels of the basal inflammatory markers C-reactive protein, interleukin-6, and tumor necrosis factor-alpha were determined. To obtain a measure of the innate immune response, 13 inflammatory markers were assessed after lipopolysaccharide (LPS) stimulation in a subsample (n=707). Subjects with chronic multisite musculoskeletal pain showed elevated levels of basal inflammatory markers compared with controls, but statistical significance was lost after adjustment for lifestyle and disease variables. For some LPS-stimulated inflammatory markers, we did find elevated levels in subjects with chronic multisite musculoskeletal pain both before and after adjustment for covariates. Pain severity was not associated with inflammation within chronic pain subjects. An enhanced innate immune response in chronic multisite musculoskeletal pain may be examined as a potential biomarker for the onset or perpetuation of chronic pain.
Collapse
Affiliation(s)
- Ellen Generaal
- Department of Psychiatry and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands Musculoskeletal Research Collaboration (Epidemiology Group), University of Aberdeen, Aberdeen, UK Department of Clinical and Health Psychology, Utrecht University, Utrecht, The Netherlands Department of Rehabilitation Medicine, VU University Medical Center, Amsterdam, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
39
|
Peng Y, Zhang L. Activation of the TLR1/2 pathway induces the shaping of the immune response status of peripheral blood leukocytes. Exp Ther Med 2014; 7:1708-1712. [PMID: 24926371 PMCID: PMC4043581 DOI: 10.3892/etm.2014.1621] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 01/02/2014] [Indexed: 02/05/2023] Open
Abstract
Toll-like receptors (TLRs) play an essential role in the activation and regulation of the innate and adaptive immune responses through the recognition of specific components of pathogens. TLR1/2 on the cell surface plays an important role in defending against Gram-positive bacteria. The aim of the present study was to examine the expressional variation of immunomodulatory molecules in peripheral blood leukocytes (PBLs) treated with the TLR1/2 agonist, Pam3Cys. The quantitative polymerase chain reaction result showed dramatically increased expression of immune-related factors treated with Pam3Cys. Antibody-chip assays confirmed that activation of TLR1/2 could induce secretion of four important immune factors [interleukin (IL)-6, IL-8, macrophage inflammatory protein-1α and interferon-β). Western-blot analysis indicated the upregulation of three significant signal kinase proteins (phosphorylated signal transducer and activator of transcription 3, extracellular signal-related kinase and c-Jun N-terminal kinase 2). The study demonstrated that there were numerous molecules involved in the immune response of PBLs stimulated by the TLR1/2 ligand. Our future studies will focus on the mechanisms of these molecules in the TLR1/2 agonist-mediated immune response.
Collapse
Affiliation(s)
- Ying Peng
- Department of Cardiology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Li Zhang
- Laboratory of Pathology, Department of Pathology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| |
Collapse
|
40
|
Abstract
Reciprocal signalling between immunocompetent cells in the central nervous system (CNS) has emerged as a key phenomenon underpinning pathological and chronic pain mechanisms. Neuronal excitability can be powerfully enhanced both by classical neurotransmitters derived from neurons, and by immune mediators released from CNS-resident microglia and astrocytes, and from infiltrating cells such as T cells. In this Review, we discuss the current understanding of the contribution of central immune mechanisms to pathological pain, and how the heterogeneous immune functions of different cells in the CNS could be harnessed to develop new therapeutics for pain control. Given the prevalence of chronic pain and the incomplete efficacy of current drugs--which focus on suppressing aberrant neuronal activity--new strategies to manipulate neuroimmune pain transmission hold considerable promise.
Collapse
|
41
|
Kwok YH, Tuke J, Nicotra LL, Grace PM, Rolan PE, Hutchinson MR. TLR 2 and 4 responsiveness from isolated peripheral blood mononuclear cells from rats and humans as potential chronic pain biomarkers. PLoS One 2013; 8:e77799. [PMID: 24204973 PMCID: PMC3813723 DOI: 10.1371/journal.pone.0077799] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 09/04/2013] [Indexed: 01/31/2023] Open
Abstract
Background Chronic pain patients have increased peripheral blood mononuclear cell Interkeukin-1β production following TLR2 and TLR4 simulation. Here we have used a human-to-rat and rat-to-human approach to further investigate whether peripheral blood immune responses to TLR agonists might be suitable for development as possible systems biomarkers of chronic pain in humans. Methods and Results Study 1: using a graded model of chronic constriction injury in rats, behavioral allodynia was assessed followed by in vitro quantification of TLR2 and TLR4 agonist-induced stimulation of IL-1β release by PBMCs and spinal cord tissues (n = 42; 6 rats per group). Statistical models were subsequently developed using the IL-1β responses, which distinguished the pain/no pain states and predicted the degree of allodynia. Study 2: the rat-derived statistical models were tested to assess their predictive utility in determining the pain status of a published human cohort that consists of a heterogeneous clinical pain population (n = 19) and a pain-free population (n = 11). The predictive ability of one of the rat models was able to distinguish pain patients from controls with a ROC AUC of 0.94. The rat model was used to predict the presence of pain in a new chronic pain cohort and was able to accurately predict the presence of pain in 28 out of the 34 chronic pain participants. Conclusions These clinical findings confirm our previous discoveries of the involvement of the peripheral immune system in chronic pain. Given that these findings are reflected in the prospective graded rat data, it suggests that the TLR response from peripheral blood and spinal cord were related to pain and these clinical findings do indeed act as system biomarkers for the chronic pain state. Hence, they provide additional impetus to the neuroimmune interaction to be a drug target for chronic pain.
Collapse
Affiliation(s)
- Yuen H. Kwok
- Discipline of Pharmacology, School of Medical Sciences, University of Adelaide, Adelaide, South Australia, Australia
- * E-mail:
| | - Jonathan Tuke
- School of Mathematical Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Lauren L. Nicotra
- Discipline of Pharmacology, School of Medical Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Peter M. Grace
- Discipline of Pharmacology, School of Medical Sciences, University of Adelaide, Adelaide, South Australia, Australia
- Department of Psychology and The Center for Neuroscience, University of Colorado at Boulder, Boulder, Colorado, United States of America
| | - Paul E. Rolan
- Discipline of Pharmacology, School of Medical Sciences, University of Adelaide, Adelaide, South Australia, Australia
- Pain and Anaesthesia Research Clinic, University of Adelaide, Adelaide, South Australia, Australia
- Pain Management Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Mark R. Hutchinson
- Department of Psychology and The Center for Neuroscience, University of Colorado at Boulder, Boulder, Colorado, United States of America
- Discipline of Physiology, School of Medical Sciences, University of Adelaide, Adelaide, South Australia, Australia
| |
Collapse
|
42
|
Johnson JL, Hutchinson MR, Williams DB, Rolan P. Medication-overuse headache and opioid-induced hyperalgesia: A review of mechanisms, a neuroimmune hypothesis and a novel approach to treatment. Cephalalgia 2012; 33:52-64. [PMID: 23144180 DOI: 10.1177/0333102412467512] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Introduction Patients with chronic headache who consume large amounts of analgesics are often encountered in clinical practice. Excessive intake of analgesics is now considered to be a cause, rather than simply a consequence, of frequent headaches, and as such the diagnosis “medication-overuse headache” (MOH) has been formulated. Despite the prevalence and clinical impact of MOH, the pathophysiology behind this disorder remains unclear and specific mechanism-based treatment options are lacking. Discussion Although most acute headache treatments have been alleged to cause MOH, here we conclude from the literature that opioids are a particularly problematic drug class consistently associated with worsening headache. MOH may not be a single entity, as each class of drug implicated may cause MOH via a different mechanism. Recent evidence indicates that chronic opioid administration may exacerbate pain in the long term by activating toll-like receptor-4 on glial cells, resulting in a pro-inflammatory state that manifests clinically as increased pain. Thus, from the available evidence it seems opioid-overuse headache is a phenomenon similar to opioid-induced hyperalgesia, which derives from a cumulative interaction between central sensitisation, due to repeated activation of nociceptive pathways by recurrent headaches, and pain facilitation due to glial activation. Conclusion Treatment strategies directed at inhibiting glial activation may be of benefit alongside medication withdrawal in the management of MOH.
Collapse
Affiliation(s)
| | | | - Desmond B Williams
- School of Pharmacy and Medical Sciences, University of South Australia, Australia
| | - Paul Rolan
- Discipline of Pharmacology, University of Adelaide, Australia
- Pain and Anaesthesia Research Clinic, Royal Adelaide Hospital, Australia
- Pain Management Unit, Royal Adelaide Hospital, Australia
| |
Collapse
|