1
|
Suárez-Pereira I, López-Martín C, Camarena-Delgado C, Llorca-Torralba M, González-Saiz F, Ruiz R, Santiago M, Berrocoso E. Nerve Injury Triggers Time-dependent Activation of the Locus Coeruleus, Influencing Spontaneous Pain-like Behavior in Rats. Anesthesiology 2024; 141:131-150. [PMID: 38602502 DOI: 10.1097/aln.0000000000005006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
BACKGROUND Dynamic changes in neuronal activity and in noradrenergic locus coeruleus (LC) projections have been proposed during the transition from acute to chronic pain. Thus, the authors explored the cellular cFos activity of the LC and its projections in conjunction with spontaneous pain-like behavior in neuropathic rats. METHODS Tyrosine hydroxylase:Cre and wild-type Long-Evans rats, males and females, were subjected to chronic constriction injury (CCI) for 2 (short-term, CCI-ST) or 30 days (long-term, CCI-LT), evaluating cFos and Fluoro-Gold expression in the LC, and its projections to the spinal cord (SC) and rostral anterior cingulate cortex (rACC). These tests were carried out under basal conditions (unstimulated) and after noxious mechanical stimulation. LC activity was evaluated through chemogenetic and pharmacologic approaches, as were its projections, in association with spontaneous pain-like behaviors. RESULTS CCI-ST enhanced basal cFos expression in the LC and in its projection to the SC, which increased further after noxious stimulation. Similar basal activation was found in the neurons projecting to the rACC, although this was not modified by stimulation. Strong basal cFos expression was found in CCI-LT, specifically in the projection to the rACC, which was again not modified by stimulation. No cFos expression was found in the CCI-LT LCipsilateral (ipsi)/contralateral (contra)→SC. Chemogenetics showed that CCI-ST is associated with greater spontaneous pain-like behavior when the LCipsi is blocked, or by selectively blocking the LCipsi→SC projection. Activation of the LCipsi or LCipsi/contra→SC dampened pain-like behavior. Moreover, Designer Receptor Exclusively Activated by Designer Drugs (DREADDs)-mediated inactivation of the CCI-ST LCipsi→rACC or CCI-LT LCipsi/contra→rACC pathway, or intra-rACC antagonism of α-adrenoreceptors, also dampens pain-like behavior. CONCLUSIONS In the short term, activation of the LC after CCI attenuates spontaneous pain-like behaviors via projections to the SC while increasing nociception via projections to the rACC. In the long term, only the projections from the LC to the rACC contribute to modulate pain-like behaviors in this model. EDITOR’S PERSPECTIVE
Collapse
Affiliation(s)
- Irene Suárez-Pereira
- Biomedical Research Networking Center for Mental Health (CIBERSAM), Institute of Health Carlos III (ISCIII), Madrid, Spain; Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, Faculty of Medicine, University of Cádiz, Cádiz, Spain; Biomedical Research and Innovation Institute of Cádiz (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain
| | - Carolina López-Martín
- Biomedical Research Networking Center for Mental Health (CIBERSAM), Institute of Health Carlos III (ISCIII), Madrid, Spain; Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, Faculty of Medicine, University of Cádiz, Cádiz, Spain; Biomedical Research and Innovation Institute of Cádiz (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain
| | - Carmen Camarena-Delgado
- Biomedical Research and Innovation Institute of Cádiz (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain; IRCCS Humanitas Research Hospital, Milan, Italy; Institute of Neuroscience (IN-CNR), National Research Council of Italy, Milan, Italy
| | - Meritxell Llorca-Torralba
- Biomedical Research Networking Center for Mental Health (CIBERSAM), Institute of Health Carlos III (ISCIII), Madrid, Spain; Biomedical Research and Innovation Institute of Cádiz (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain; Neuropsychopharmacology and Psychobiology Research Group, Department of Cell Biology and Histology, University of Cádiz, Cádiz, Spain
| | - Francisco González-Saiz
- Biomedical Research Networking Center for Mental Health (CIBERSAM), Institute of Health Carlos III (ISCIII), Madrid, Spain; Department of Neuroscience, Faculty of Medicine, University of Cádiz, Cádiz, Spain; Community Mental Health Unit of Villamartin, University Hospital of Jerez de la Frontera, Cádiz, Spain
| | - Rocío Ruiz
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Institute of Biomedicine of Sevilla (IBiS) - University Hospital Virgen del Rocío/CSIC/University of Sevilla, Sevilla, Spain
| | - Martiniano Santiago
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Institute of Biomedicine of Sevilla (IBiS) - University Hospital Virgen del Rocío/CSIC/University of Sevilla, Sevilla, Spain
| | - Esther Berrocoso
- Biomedical Research Networking Center for Mental Health (CIBERSAM), Institute of Health Carlos III (ISCIII), Madrid, Spain; Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, Faculty of Medicine, University of Cádiz, Cádiz, Spain; Biomedical Research and Innovation Institute of Cádiz (INIBICA), Puerta del Mar University Hospital, Cádiz, Spain
| |
Collapse
|
2
|
Louçano M, Coelho A, Chambel SS, Prudêncio C, Cruz CD, Tavares I. Noradrenergic Pathways Involved in Micturition in an Animal Model of Hydrocephalus-Implications for Urinary Dysfunction. Biomedicines 2024; 12:215. [PMID: 38255319 PMCID: PMC10813199 DOI: 10.3390/biomedicines12010215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 01/08/2024] [Accepted: 01/16/2024] [Indexed: 01/24/2024] Open
Abstract
Hydrocephalus is characterized by enlargement of the cerebral ventricles, accompanied by distortion of the periventricular tissue. Patients with hydrocephalus usually experience urinary impairments. Although the underlying etiology is not fully described, the effects of hydrocephalus in the neuronal network responsible for the control of urination, which involves periventricular areas, including the periaqueductal gray (PAG) and the noradrenergic locus coeruleus (LC). In this study, we aimed to investigate the mechanisms behind urinary dysfunction in rats with kaolin-induced hydrocephalus. For that purpose, we used a validated model of hydrocephalus-the rat injected with kaolin in the cisterna magna-also presents urinary impairments in order to investigate the putative involvement of noradrenergic control from the brain to the spinal cord Onuf's nucleus, a key area in the motor control of micturition. We first evaluated bladder contraction capacity using cystometry. Since our previous characterization of the LC in hydrocephalic animals showed increased levels of noradrenaline, we then evaluated the noradrenergic innervation of the spinal cord's Onuf's nucleus by measuring levels of dopamine β-hydroxylase (DBH). We also evaluated the expression of the c-Fos protooncogene, the most widely used marker of neuronal activation, in the ventrolateral PAG (vlPAG), an area that plays a major role in the control of urination by its indirect control of the LC via pontine micturition center. Hydrocephalic rats showed an increased frequency of bladder contractions and lower minimum pressure. These animals also presented increased DBH levels at the Onuf´s nucleus, along with decreased c-Fos expression in the vlPAG. The present findings suggest that impairments in urinary function during hydrocephalus may be due to alterations in descending noradrenergic modulation. We propose that the effects of hydrocephalus in the decrease of vlPAG neuronal activation lead to a decrease in the control over the LC. The increased availability of noradrenaline production at the LC probably causes an exaggerated micturition reflex due to the increased innervation of the Onuf´s nucleus, accounting for the urinary impairments detected in hydrocephalic animals. The results of the study provide new insights into the neuronal underlying mechanisms of urinary dysfunction in hydrocephalus. Further research is needed to fully evaluate the translational perspectives of the current findings.
Collapse
Affiliation(s)
- Marta Louçano
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal; (M.L.)
- IBMC-Institute of Molecular and Cell Biology, University of Porto, 4200-135 Porto, Portugal
- I3S-Institute of Investigation and Innovation in Health, University of Porto, 4200-135 Porto, Portugal
- Chemical and Biomolecule Sciences, School of Health, Polytechnic of Porto, 4200-072 Porto, Portugal
| | - Ana Coelho
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal; (M.L.)
- IBMC-Institute of Molecular and Cell Biology, University of Porto, 4200-135 Porto, Portugal
- I3S-Institute of Investigation and Innovation in Health, University of Porto, 4200-135 Porto, Portugal
| | - Sílvia Sousa Chambel
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal; (M.L.)
- IBMC-Institute of Molecular and Cell Biology, University of Porto, 4200-135 Porto, Portugal
- I3S-Institute of Investigation and Innovation in Health, University of Porto, 4200-135 Porto, Portugal
| | - Cristina Prudêncio
- I3S-Institute of Investigation and Innovation in Health, University of Porto, 4200-135 Porto, Portugal
- Chemical and Biomolecule Sciences, School of Health, Polytechnic of Porto, 4200-072 Porto, Portugal
- Center for Translational Health and Medical Biotechnology Research (TBIO), Polytechnic of Porto, 4200-072 Porto, Portugal
| | - Célia Duarte Cruz
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal; (M.L.)
- IBMC-Institute of Molecular and Cell Biology, University of Porto, 4200-135 Porto, Portugal
- I3S-Institute of Investigation and Innovation in Health, University of Porto, 4200-135 Porto, Portugal
| | - Isaura Tavares
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal; (M.L.)
- IBMC-Institute of Molecular and Cell Biology, University of Porto, 4200-135 Porto, Portugal
- I3S-Institute of Investigation and Innovation in Health, University of Porto, 4200-135 Porto, Portugal
| |
Collapse
|
3
|
Norris MR, Kuo CC, Kim JR, Dunn SS, Borges G, Thang LV, McCall JG. Endogenous opioids gate the locus coeruleus pain generator. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.20.562785. [PMID: 37961541 PMCID: PMC10634678 DOI: 10.1101/2023.10.20.562785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The locus coeruleus (LC) plays a paradoxical role in chronic pain. Although largely known as a potent source of endogenous analgesia, increasing evidence suggests injury can transform the LC into a chronic pain generator. We sought to clarify the role of this system in pain. Here, we show optogenetic inhibition of LC activity is acutely antinociceptive. Following long-term spared nerve injury, the same LC inhibition is analgesic - further supporting its pain generator function. To identify inhibitory substrates that may naturally serve this function, we turned to endogenous LC mu opioid receptors (LC-MOR). These receptors provide powerful LC inhibition and exogenous activation of LC-MOR is antinociceptive. We therefore hypothesized that endogenous LC-MOR-mediated inhibition is critical to how the LC modulates pain. Using cell type-selective conditional knockout and rescue of LC-MOR receptor signaling, we show these receptors bidirectionally regulate thermal and mechanical hyperalgesia - providing a functional gate on the LC pain generator.
Collapse
Affiliation(s)
- Makenzie R. Norris
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Chao-Cheng Kuo
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Jenny R. Kim
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Samantha S. Dunn
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Gustavo Borges
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Loc V. Thang
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Jordan G. McCall
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA; Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA; Washington University Pain Center, Washington University in St. Louis, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA
| |
Collapse
|
4
|
Takemura M, Niki K, Okamoto Y, Tamura H, Kawamura T, Kohno M, Matsuda Y, Ikeda K. Differences in the Analgesic Effect of Opioids on Pain in Cancer Patients With Spinal Metastases. Palliat Med Rep 2023; 4:220-230. [PMID: 37637760 PMCID: PMC10457616 DOI: 10.1089/pmr.2023.0018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/14/2023] [Indexed: 08/29/2023] Open
Abstract
Background Spinal metastasis pain includes both inflammatory and neuropathic pain, and opioids, which have only a μ-opioid receptor-stimulating effect, are generally less effective in neuropathic pain. However, no previous study has been conducted for the comparisons of the efficacy of opioids in treating spinal metastasis pain. Objective To compare the efficacy of tapentadol and methadone with other opioids for back pain caused by a metastatic spinal tumor. Design Retrospective cohort study. Setting/Subjects A total of 274 patients were enrolled, who started a tapentadol extended-release tablet, methadone tablet, hydromorphone extended-release tablet, oxycodone extended-release tablet, or transdermal fentanyl patch for cancer pain due to spinal metastasis in Japan from January 1, 2013 to October 31, 2021. Measurements The primary endpoint, the difference in the numerical rating scale (NRS) scores before and seven days after each opioid administration, was compared among the five groups. Results In patients with numbness, a decrease of the NRS score on day seven compared with before starting each opioid was significantly higher in the tapentadol group than those in the hydromorphone, oxycodone, and fentanyl groups and comparable to that in the methadone group. In patients without numbness, no significant differences were observed in decreases of the NRS scores on day seven among the five groups. Conclusions Tapentadol and methadone may be more effective than hydromorphone, oxycodone, and fentanyl for cancer pain due to spinal metastasis with numbness.
Collapse
Affiliation(s)
- Miho Takemura
- Department of Clinical Pharmacy Research and Education, Osaka University Graduate School of Pharmaceutical Sciences, Suita, Japan
- Department of Pharmacy, Ashiya Municipal Hospital, Ashiya, Japan
| | - Kazuyuki Niki
- Department of Clinical Pharmacy Research and Education, Osaka University Graduate School of Pharmaceutical Sciences, Suita, Japan
- Department of Pharmacy, Ashiya Municipal Hospital, Ashiya, Japan
| | - Yoshiaki Okamoto
- Department of Pharmacy, Ashiya Municipal Hospital, Ashiya, Japan
| | - Hiroshi Tamura
- Department of Rehabilitation, and Ashiya Municipal Hospital, Ashiya, Japan
| | - Tomohiro Kawamura
- Department of Palliative Care, Ashiya Municipal Hospital, Ashiya, Japan
| | - Makie Kohno
- Department of Palliative Care, Ashiya Municipal Hospital, Ashiya, Japan
| | - Yoshinobu Matsuda
- Department of Palliative Care, Ashiya Municipal Hospital, Ashiya, Japan
| | - Kenji Ikeda
- Department of Clinical Pharmacy Research and Education, Osaka University Graduate School of Pharmaceutical Sciences, Suita, Japan
| |
Collapse
|
5
|
Hayashi Y, Otsuji J, Oshima E, Hitomi S, Ni J, Urata K, Shibuta I, Iwata K, Shinoda M. Microglia cause structural remodeling of noradrenergic axon in the trigeminal spinal subnucleus caudalis after infraorbital nerve injury in rats. Brain Behav Immun Health 2023; 30:100622. [PMID: 37101903 PMCID: PMC10123072 DOI: 10.1016/j.bbih.2023.100622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 04/01/2023] [Accepted: 04/07/2023] [Indexed: 04/28/2023] Open
Abstract
The dysfunction of descending noradrenergic (NAergic) modulation in second-order neurons has long been observed in neuropathic pain. In clinical practice, antidepressants that increase noradrenaline levels in the synaptic cleft are used as first-line agents, although adequate analgesia has not been occasionally achieved. One of the hallmarks of neuropathic pain in the orofacial regions is microglial abnormalities in the trigeminal spinal subnucleus caudalis (Vc). However, until now, the direct interaction between descending NAergic system and Vc microglia in orofacial neuropathic pain has not been explored. We found that reactive microglia ingested the dopamine-β-hydroxylase (DβH)-positive fraction, NAergic fibers, in the Vc after infraorbital nerve injury (IONI). Major histocompatibility complex class I (MHC-I) was upregulated in Vc microglia after IONI. Interferon-γ (IFNγ) was de novo induced in trigeminal ganglion (TG) neurons following IONI, especially in C-fiber neurons, which conveyed to the central terminal of TG neurons. Gene silencing of IFNγ in the TG reduced MHC-I expression in the Vc after IONI. Intracisternal administration of exosomes from IFNγ-stimulated microglia elicited mechanical allodynia and a decrease in DβH in the Vc, which did not occur when exosomal MHC-I was knocked down. Similarly, in vivo MHC-I knockdown in Vc microglia attenuated the development of mechanical allodynia and a decrease in DβH in the Vc after IONI. These results show that microglia-derived MHC-I causes a decrease in NAergic fibers, culminating in orofacial neuropathic pain.
Collapse
Affiliation(s)
- Yoshinori Hayashi
- Department of Physiology, Nihon University School of Dentistry, Chiyoda-ku, Tokyo, 101-8310, Japan
- Corresponding author. Department of Physiology, Nihon University School of Dentistry, 1-8-13, Kandasurugadai, Chiyoda-ku, Tokyo, 101-8301, Japan.
| | - Jo Otsuji
- Department of Physiology, Nihon University School of Dentistry, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Eri Oshima
- Department of Physiology, Nihon University School of Dentistry, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Suzuro Hitomi
- Department of Physiology, Nihon University School of Dentistry, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Junjun Ni
- Key Laboratory of Molecular Medicine and Biotherapy in the Ministry of Industry and Information Technology, Department of Biology, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Kentaro Urata
- Department of Complete Denture Prosthodontics, Nihon University School of Dentistry, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Ikuko Shibuta
- Department of Physiology, Nihon University School of Dentistry, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Koichi Iwata
- Department of Physiology, Nihon University School of Dentistry, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Masamichi Shinoda
- Department of Physiology, Nihon University School of Dentistry, Chiyoda-ku, Tokyo, 101-8310, Japan
| |
Collapse
|
6
|
Da Vitoria Lobo ME, Madden R, Liddell S, Hirashima M, Hulse RP. Spinal cord vascular degeneration impairs duloxetine penetration. FRONTIERS IN PAIN RESEARCH 2023; 4:1190440. [PMID: 37325676 PMCID: PMC10262048 DOI: 10.3389/fpain.2023.1190440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 05/03/2023] [Indexed: 06/17/2023] Open
Abstract
Introduction Chronic pain is a prevalent physically debilitating health-related morbidity. Frontline analgesics are inadequate, providing only partial pain relief in only a proportion of the patient cohort. Here, we explore whether alterations in spinal cord vascular perfusion are a factor in reducing the analgesic capability of the noradrenaline reuptake inhibitor, duloxetine. Method An established rodent model of spinal cord vascular degeneration was used. Endothelial-specific vascular endothelial growth factor receptor 2 knockout mouse was induced via hydroxytamoxifen administered via intrathecal injection. Duloxetine was administered via intraperitoneal injection, and nociceptive behavioural testing was performed in both WT and VEGFR2KO mice. LC-MS/MS was performed to explore the accumulation of duloxetine in the spinal cord in WT and VEGFR2KO mice. Results Spinal cord vascular degeneration leads to heat hypersensitivity and a decline in capillary perfusion. The integrity of noradrenergic projections (dopa - hydroxylase labelled) in the dorsal horn remained unaltered in WT and VEGFR2KO mice. There was an association between dorsal horn blood flow with the abundance of accumulated duloxetine in the spinal cord and analgesic capacity. In VEGFR2KO mice, the abundance of duloxetine in the lumbar spinal cord was reduced and was correlated with reduced anti-nociceptive capability of duloxetine. Discussion Here, we show that an impaired vascular network in the spinal cord impairs the anti-nociceptive action of duloxetine. This highlights that the spinal cord vascular network is crucial to maintaining the efficacy of analgesics to provide pain relief.
Collapse
Affiliation(s)
- M. E Da Vitoria Lobo
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine University of Nottingham, Nottingham, United Kingdom
| | - R Madden
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine University of Nottingham, Nottingham, United Kingdom
| | - S Liddell
- Exonate Ltd., Nottingham, United Kingdom
| | - M Hirashima
- Division of Pharmacology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - R. P Hulse
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine University of Nottingham, Nottingham, United Kingdom
- School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
| |
Collapse
|
7
|
Wong F, Reddy A, Rho Y, Vollert J, Strutton PH, Hughes SW. Responders and nonresponders to topical capsaicin display distinct temporal summation of pain profiles. Pain Rep 2023; 8:e1071. [PMID: 37731476 PMCID: PMC10508395 DOI: 10.1097/pr9.0000000000001071] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 12/15/2022] [Accepted: 02/02/2023] [Indexed: 09/22/2023] Open
Abstract
Introduction Topical application of capsaicin can produce an ongoing pain state in healthy participants. However, approximately one-third report no pain response (ie, nonresponders), and the reasons for this are poorly understood. Objectives In this study, we investigated temporal summation of pain (TSP) profiles, pain ratings and secondary hyperalgesia responses in responders and nonresponders to 1% topical capsaicin cream. Methods Assessments were made at baseline and then during an early (ie, 15 minutes) and late (ie, 45 minutes) time points post-capsaicin in 37 healthy participants. Results Participants reporting a visual analogue scale (VAS) rating of >50 were defined as responders (n = 24) and those with <50 VAS rating were defined as nonresponders (n = 13). There was a facilitation of TSP during the transition from an early to the late time point post-capsaicin (P<0.001) and the development of secondary hyperalgesia (P<0.05) in the responder group. Nonresponders showed no changes in TSP or secondary hyperalgesia during the early and late time points. There was an association between baseline TSP scores and the later development of a responder or nonresponder phenotype (r = 0.36; P = 0.03). Receiver operating characteristic analysis revealed that baseline TSP works as a good response predictor at an individual level (area under the curve = 0.75). Conclusion These data suggest that responders and nonresponders have different facilitatory pain mechanisms. The assessment of TSP may help to identify participants with stronger endogenous pain facilitation who may be more likely to respond to topical capsaicin.
Collapse
Affiliation(s)
- Felyx Wong
- The Nick Davey Laboratory, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Aditi Reddy
- The Nick Davey Laboratory, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Yeanuk Rho
- The Nick Davey Laboratory, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Jan Vollert
- Pain Research, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Paul H. Strutton
- The Nick Davey Laboratory, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Sam W. Hughes
- The Pain Modulation Laboratory, Brain Research and Imaging Centre (BRIC), School of Psychology, Faculty of Health, University of Plymouth, Plymouth, United Kingdom
| |
Collapse
|
8
|
Pereira-Silva R, Serrão P, Lourença Neto F, Martins I. Diffuse noxious inhibitory controls in chronic joint inflammatory Pain: Study of the descending serotonergic modulation mediated through 5HT3 receptors. NEUROBIOLOGY OF PAIN (CAMBRIDGE, MASS.) 2023; 13:100123. [PMID: 36915290 PMCID: PMC10006856 DOI: 10.1016/j.ynpai.2023.100123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/27/2023] [Accepted: 02/27/2023] [Indexed: 03/05/2023]
Abstract
The loss of diffuse noxious inhibitory controls (DNIC) is recognized as a predictor of chronic pain. Mechanistically, DNIC produces analgesia by a heterotopically applied conditioning-noxious stimulus (CS) and yet underexplored descending modulatory inputs. Here, we aimed at studying DNIC in monoarthritis (MA) by exploring the spinal component of the descending serotonergic system, specifically 5-hydroxytryptamine 3 receptors (5-HT3R). MA was induced in male Wistar rats by tibiotarsal injection of complete Freund's adjuvant. Mechanical hyperalgesia and DNIC were assessed weekly by the Randall-Selitto test. Immunohistochemistry was used to quantify spinal 5-HT3R, and tryptophan hydroxylase (TPH) colocalization with phosphorylated extracellular signal-regulated protein kinases 1/2 at the rostroventromedial medulla (RVM). Spinal serotonin (5-HT) was quantified by HPLC. The effects of intrathecal ondansetron, a 5-HT3R antagonist, were assessed on mechanical hyperalgesia and DNIC. MA resulted in a prolonged steady-state mechanical hyperalgesia. In contrast, DNIC peaked after 28 days, decreasing afterwards until extinction at 42 days. At this later timepoint, MA rats showed increased: (i) spinal 5-HT3R and 5-HT levels, (ii) neuronal serotonergic activation and TPH expression at the RVM. Ondansetron reversed mechanical hyperalgesia and restored DNIC, regardless of being administered before or after CS. However, data variability was higher upon administration before CS in MA-animals. Prolonged MA upregulates the descending serotonergic modulation, which simultaneously results in increased nociception and DNIC extinction, through 5-HT3R. Our data suggest a role for spinal 5-HT3R in the top-down modulation of DNIC. Additionally, these receptors may also be involved in the bottom-up circuitry implicated in the trigger of DNIC.
Collapse
Affiliation(s)
- Raquel Pereira-Silva
- Instituto de Investigação e Inovação em Saúde da Universidade do Porto (I3S). Rua Alfredo Allen 208, 4200 393 Porto, Portugal.,Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto. Rua Alfredo Allen 208, 4200-393 Porto, Portugal.,Departamento de Biomedicina - Unidade de Biologia Experimental, Faculdade de Medicina, Universidade do Porto. Alameda Prof. Hernâni Monteiro 4200-319 Porto, Portugal
| | - Paula Serrão
- Departamento de Biomedicina - Unidade de Farmacologia e Terapêutica, Faculdade de Medicina, Universidade do Porto. Alameda Prof. Hernâni Monteiro 4200-319 Porto, Portugal.,MedInUP - Center for Drug Discovery and Innovative Medicines, University of Porto. Alameda Prof. Hernâni Monteiro 4200-319 Porto, Portugal
| | - Fani Lourença Neto
- Instituto de Investigação e Inovação em Saúde da Universidade do Porto (I3S). Rua Alfredo Allen 208, 4200 393 Porto, Portugal.,Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto. Rua Alfredo Allen 208, 4200-393 Porto, Portugal.,Departamento de Biomedicina - Unidade de Biologia Experimental, Faculdade de Medicina, Universidade do Porto. Alameda Prof. Hernâni Monteiro 4200-319 Porto, Portugal
| | - Isabel Martins
- Instituto de Investigação e Inovação em Saúde da Universidade do Porto (I3S). Rua Alfredo Allen 208, 4200 393 Porto, Portugal.,Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto. Rua Alfredo Allen 208, 4200-393 Porto, Portugal.,Departamento de Biomedicina - Unidade de Biologia Experimental, Faculdade de Medicina, Universidade do Porto. Alameda Prof. Hernâni Monteiro 4200-319 Porto, Portugal
| |
Collapse
|
9
|
Patra PH, Tench B, Hitrec T, Holmes F, Drake R, Cerritelli S, Spanswick D, Pickering AE. Pro-Opiomelanocortin (POMC) neurons in the nucleus of the solitary tract mediate endorphinergic endogenous analgesia in mice. Pain 2022; 164:1051-1066. [PMID: 36448978 DOI: 10.1097/j.pain.0000000000002802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Accepted: 09/27/2022] [Indexed: 12/02/2022]
Abstract
ABSTRACT The nucleus of the solitary tract (NTS) contains pro-opiomelanocortin (POMC) neurons which are one of the two major sources of β-endorphin in the brain. The functional role of these NTS POMC neurons in nociceptive and cardiorespiratory function is debated. We have shown that NTS POMC optogenetic activation produces bradycardia and transient apnoea in a working heart brainstem preparation and chemogenetic activation with an engineered ion channel (PSAM) produced opioidergic analgesia in vivo . To better define the role of the NTS POMC neurons in behaving animals, we adopted in vivo optogenetics (ChrimsonR) and excitatory/inhibitory chemogenetic DREADD (hM3Dq/hM4Di) strategies in POMC-Cre mice. We show that optogenetic activation of NTS POMC neurons produces time-locked, graded, transient bradycardia and bradypnoea in anaesthetised mice which is naloxone sensitive (1 mg/kg, i.p) suggesting a role of β-endorphin. Both optogenetic and chemogenetic activation of NTS POMC neurons produces sustained thermal analgesia in behaving mice which can be blocked by naloxone. It also produced analgesia in inflammatory pain (carrageenan) but not in a neuropathic pain model (tibial nerve transection). Inhibiting NTS POMC neurons does not produce any effect on basal nociception but inhibits stress-induced analgesia (unlike inhibition of arcuate POMC neurons). Activation of NTS POMC neuronal populations in conscious mice did not cause respiratory depression, anxiety or locomotor deficit (in open field) nor affective preference. These findings indicate that NTS POMC neurons play a key role in the generation of endorphinergic endogenous analgesia and can also regulate cardiorespiratory function.
Collapse
Affiliation(s)
- Pabitra Hriday Patra
- Anaesthesia, Pain & Critical Care Research, School of Physiology, Pharmacology and Neuroscience, University of Bristol, BS8 1TD, UK
| | - Becks Tench
- Anaesthesia, Pain & Critical Care Research, School of Physiology, Pharmacology and Neuroscience, University of Bristol, BS8 1TD, UK
| | - Timna Hitrec
- Anaesthesia, Pain & Critical Care Research, School of Physiology, Pharmacology and Neuroscience, University of Bristol, BS8 1TD, UK
| | - Fiona Holmes
- Anaesthesia, Pain & Critical Care Research, School of Physiology, Pharmacology and Neuroscience, University of Bristol, BS8 1TD, UK
| | - Robert Drake
- Anaesthesia, Pain & Critical Care Research, School of Physiology, Pharmacology and Neuroscience, University of Bristol, BS8 1TD, UK
| | - Serena Cerritelli
- Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - David Spanswick
- Neurosolutions, University of Warwick, Gibbet Hill Road, Coventry, West Midlands, CV4 7AL, UK
| | - Anthony Edward Pickering
- Anaesthesia, Pain & Critical Care Research, School of Physiology, Pharmacology and Neuroscience, University of Bristol, BS8 1TD, UK
| |
Collapse
|
10
|
Li J, Wei Y, Zhou J, Zou H, Ma L, Liu C, Xiao Z, Liu X, Tan X, Yu T, Cao S. Activation of locus coeruleus-spinal cord noradrenergic neurons alleviates neuropathic pain in mice via reducing neuroinflammation from astrocytes and microglia in spinal dorsal horn. J Neuroinflammation 2022; 19:123. [PMID: 35624514 PMCID: PMC9145151 DOI: 10.1186/s12974-022-02489-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 05/15/2022] [Indexed: 11/10/2022] Open
Abstract
Background The noradrenergic neurons of locus coeruleus (LC) project to the spinal dorsal horn (SDH), and release norepinephrine (NE) to inhibit pain transmission. However, its effect on pathological pain and the cellular mechanism in the SDH remains unclear. This study aimed to explore the analgesic effects and the anti-neuroinflammation mechanism of LC-spinal cord noradrenergic pathway (LC:SC) in neuropathic pain (NP) mice with sciatic chronic constriction injury. Methods The Designer Receptors Exclusively Activated by Designer Drugs (DREADD) was used to selectively activate LC:SC. Noradrenergic neuron-specific retro–adeno-associated virus was injected to the spinal cord. Pain threshold, LC and wide dynamic range (WDR) neuron firing, neuroinflammation (microglia and astrocyte activation, cytokine expression), and α2AR expression in SDH were evaluated. Results Activation of LC:SC with DREADD increased the mechanical and thermal nociceptive thresholds and reduced the WDR neuron firing. LC:SC activation (daily, 7 days) downregulated TNF-α and IL-1β expression, upregulated IL-4 and IL-10 expression in SDH, and inhibited microglia and astrocytes activation in NP mice. Immunofluorescence double staining confirmed that LC:SC activation decreased the expression of cytokines in microglia of the SDH. In addition, the effects of LC:SC activation could be reversed by intrathecal injection of yohimbine. Immunofluorescence of SDH showed that NE receptor α2B-AR was highly expressed in microglia in CCI mice. Conclusion These findings indicate that selective activation of LC:SC alleviates NP in mice by increasing the release of NE and reducing neuroinflammation of astrocytes and microglia in SDH. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-022-02489-9.
Collapse
Affiliation(s)
- Juan Li
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Street, Zunyi, 563000, Guizhou, China.,Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, 149 Dalian Street, Zunyi, 563000, Guizhou, China
| | - Yiyong Wei
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Street, Zunyi, 563000, Guizhou, China.,Guizhou Key Lab of Anesthesia and Organ Protection, Zunyi Medical University, 6 West Xuefu Street, Zunyi, 563099, Guizhou, China
| | - Junli Zhou
- Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, 149 Dalian Street, Zunyi, 563000, Guizhou, China
| | - Helin Zou
- Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, 149 Dalian Street, Zunyi, 563000, Guizhou, China
| | - Lulin Ma
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Street, Zunyi, 563000, Guizhou, China
| | - Chengxi Liu
- Guizhou Key Lab of Anesthesia and Organ Protection, Zunyi Medical University, 6 West Xuefu Street, Zunyi, 563099, Guizhou, China
| | - Zhi Xiao
- Guizhou Key Lab of Anesthesia and Organ Protection, Zunyi Medical University, 6 West Xuefu Street, Zunyi, 563099, Guizhou, China
| | - Xingfeng Liu
- Guizhou Key Lab of Anesthesia and Organ Protection, Zunyi Medical University, 6 West Xuefu Street, Zunyi, 563099, Guizhou, China
| | - Xinran Tan
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Street, Zunyi, 563000, Guizhou, China.,Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, 149 Dalian Street, Zunyi, 563000, Guizhou, China
| | - Tian Yu
- Guizhou Key Lab of Anesthesia and Organ Protection, Zunyi Medical University, 6 West Xuefu Street, Zunyi, 563099, Guizhou, China
| | - Song Cao
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Street, Zunyi, 563000, Guizhou, China. .,Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, 149 Dalian Street, Zunyi, 563000, Guizhou, China. .,Guizhou Key Lab of Anesthesia and Organ Protection, Zunyi Medical University, 6 West Xuefu Street, Zunyi, 563099, Guizhou, China.
| |
Collapse
|
11
|
Nerve injury induces transient locus coeruleus activation over time: role of the locus coeruleus-dorsal reticular nucleus pathway. Pain 2022; 163:943-954. [PMID: 35025190 DOI: 10.1097/j.pain.0000000000002457] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 08/05/2021] [Indexed: 01/13/2023]
Abstract
ABSTRACT The transition from acute to chronic pain results in maladaptive brain remodeling, as characterized by sensorial hypersensitivity and the ensuing appearance of emotional disorders. Using the chronic constriction injury of the sciatic nerve as a model of neuropathic pain in male Sprague-Dawley rats, we identified time-dependent plasticity of locus coeruleus (LC) neurons related to the site of injury, ipsilateral (LCipsi) or contralateral (LCcontra) to the lesion, hypothesizing that the LC→dorsal reticular nucleus (DRt) pathway is involved in the pathological nociception associated with chronic pain. LCipsi inactivation with lidocaine increased cold allodynia 2 days after nerve injury but not later. However, similar blockade of LCcontra reduced cold allodynia 7 and 30 days after inducing neuropathy but not earlier. Furthermore, lidocaine blockade of the LCipsi or LCcontra reversed pain-induced depression 30 days after neuropathy. Long-term pain enhances phosphorylated cAMP-response element binding protein expression in the DRtcontra but not in the DRtipsi. Moreover, inactivation of the LCcontra→DRtcontra pathway using dual viral-mediated gene transfer of designer receptor exclusively activated by designer drugs produced consistent analgesia in evoked and spontaneous pain 30 days postinjury. This analgesia was similar to that produced by spinal activation of α2-adrenoreceptors. Furthermore, chemogenetic inactivation of the LCcontra→DRtcontra pathway induced depressive-like behaviour in naïve animals, but it did not modify long-term pain-induced depression. Overall, nerve damage activates the LCipsi, which temporally dampens the neuropathic phenotype. However, the ensuing activation of a LCcontra→DRtcontra facilitatory pain projection contributes to chronic pain, whereas global bilateral LC activation contributes to associated depressive-like phenotype.
Collapse
|
12
|
Suárez-Pereira I, Llorca-Torralba M, Bravo L, Camarena-Delgado C, Soriano-Mas C, Berrocoso E. The Role of the Locus Coeruleus in Pain and Associated Stress-Related Disorders. Biol Psychiatry 2022; 91:786-797. [PMID: 35164940 DOI: 10.1016/j.biopsych.2021.11.023] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 11/24/2021] [Accepted: 11/26/2021] [Indexed: 12/26/2022]
Abstract
The locus coeruleus (LC)-noradrenergic system is the main source of noradrenaline in the central nervous system and is involved intensively in modulating pain and stress-related disorders (e.g., major depressive disorder and anxiety) and in their comorbidity. However, the mechanisms involving the LC that underlie these effects have not been fully elucidated, in part owing to the technical difficulties inherent in exploring such a tiny nucleus. However, novel research tools are now available that have helped redefine the LC system, moving away from the traditional view of LC as a homogeneous structure that exerts a uniform influence on neural activity. Indeed, innovative techniques such as DREADDs (designer receptors exclusively activated by designer drugs) and optogenetics have demonstrated the functional heterogeneity of LC, and novel magnetic resonance imaging applications combined with pupillometry have opened the way to evaluate LC activity in vivo. This review aims to bring together the data available on the efferent activity of the LC-noradrenergic system in relation to pain and its comorbidity with anxiodepressive disorders. Acute pain triggers a robust LC stress response, producing spinal cord-mediated endogenous analgesia while promoting aversion, vigilance, and threat detection through its ascending efferents. However, this protective biological system fails in chronic pain, and LC activity produces pain facilitation, anxiety, increased aversive memory, and behavioral despair, acting at the medulla, prefrontal cortex, and amygdala levels. Thus, the activation/deactivation of specific LC projections contributes to different behavioral outcomes in the shift from acute to chronic pain.
Collapse
Affiliation(s)
- Irene Suárez-Pereira
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, Cádiz, Spain; Instituto de Investigación e Innovación Biomédica de Cádiz, Hospital Universitario Puerta del Mar, Cádiz, Spain; Centro de Investigación Biomédica en Red de Salud Mental, Instituto de Salud Carlos III, Madrid, Spain
| | - Meritxell Llorca-Torralba
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Cádiz, Spain; Instituto de Investigación e Innovación Biomédica de Cádiz, Hospital Universitario Puerta del Mar, Cádiz, Spain; Centro de Investigación Biomédica en Red de Salud Mental, Instituto de Salud Carlos III, Madrid, Spain
| | - Lidia Bravo
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, Cádiz, Spain; Instituto de Investigación e Innovación Biomédica de Cádiz, Hospital Universitario Puerta del Mar, Cádiz, Spain; Centro de Investigación Biomédica en Red de Salud Mental, Instituto de Salud Carlos III, Madrid, Spain
| | - Carmen Camarena-Delgado
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Cádiz, Spain; Instituto de Investigación e Innovación Biomédica de Cádiz, Hospital Universitario Puerta del Mar, Cádiz, Spain
| | - Carles Soriano-Mas
- Centro de Investigación Biomédica en Red de Salud Mental, Instituto de Salud Carlos III, Madrid, Spain; Department of Psychiatry, Bellvitge University Hospital, Bellvitge Biomedical Research Institute, Barcelona, Spain; Department of Psychobiology and Methodology in Health Sciences, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Esther Berrocoso
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Cádiz, Spain; Instituto de Investigación e Innovación Biomédica de Cádiz, Hospital Universitario Puerta del Mar, Cádiz, Spain; Centro de Investigación Biomédica en Red de Salud Mental, Instituto de Salud Carlos III, Madrid, Spain.
| |
Collapse
|
13
|
Patel R, Lumb BM, Bannister K. Editorial: Plasticity of Endogenous Pain Modulatory Circuits in Neuropathy. FRONTIERS IN PAIN RESEARCH 2022; 2:776948. [PMID: 35295507 PMCID: PMC8915642 DOI: 10.3389/fpain.2021.776948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 09/24/2021] [Indexed: 12/03/2022] Open
Affiliation(s)
- Ryan Patel
- Wolfson Centre for Age Related Diseases, King's College London, London, United Kingdom
| | - Bridget M Lumb
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom
| | - Kirsty Bannister
- Wolfson Centre for Age Related Diseases, King's College London, London, United Kingdom
| |
Collapse
|
14
|
Juri T, Fujimoto Y, Suehiro K, Nishikawa K, Mori T. Participation of the descending noradrenergic inhibitory system in the anti-hyperalgesic effect of acetaminophen in a rat model of inflammation. Life Sci 2021; 286:120030. [PMID: 34627774 DOI: 10.1016/j.lfs.2021.120030] [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: 07/16/2021] [Revised: 09/25/2021] [Accepted: 10/01/2021] [Indexed: 11/18/2022]
Abstract
AIMS This study investigated the relationship between the analgesic efficacy of acetaminophen and the descending noradrenergic systems using rodent models of inflammatory pain. MAIN METHODS Inflammatory pain models were established by carrageenan injection into rats' paws. The models were defined as acute (4 h after carrageenan injection), subacute (24 h after carrageenan injection), and late (1 week after carrageenan injection) phase. To evaluate intravenous acetaminophen treatment, the withdrawal threshold to mechanical stimuli was assessed simultaneously with in vivo microdialysis assay of noradrenaline levels in the locus coeruleus (LC). Further analyses were performed to observe the effect of yohimbine on the treatment and the impact of AM404 treatment, a metabolite of acetaminophen, on noradrenaline levels in the LC. KEY FINDINGS In all phases, intravenous acetaminophen had a significant anti-hyperalgesic effect (p < 0.05). There was a significant time-dependent increase in the noradrenaline concentration within the LC (acetaminophen versus saline treatment; at 30 min, p < 0.001; 60 min, p < 0.01) in the subacute pain model, but not in the acute and late phase pain models. Intrathecal pre-injection of yohimbine attenuated the anti-hyperalgesic effect after acetaminophen injection only in the subacute model (p < 0.05). In the subacute pain model, intracerebroventricular administration of AM404 showed the same trend in noradrenaline levels as acetaminophen administration (AM404 versus vehicle group at 30 min, p < 0.001). SIGNIFICANCE We found the descending noradrenergic inhibitory system is involved in the antinociceptive action of acetaminophen in the subacute phase of inflammatory pain.
Collapse
Affiliation(s)
- Takashi Juri
- Department of Anesthesiology, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Yohei Fujimoto
- Department of Anesthesiology, Osaka City University Graduate School of Medicine, Osaka, Japan.
| | - Koichi Suehiro
- Department of Anesthesiology, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Kiyonobu Nishikawa
- Department of Anesthesiology, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Takashi Mori
- Department of Anesthesiology, Osaka City University Graduate School of Medicine, Osaka, Japan
| |
Collapse
|
15
|
Llorca-Torralba M, Camarena-Delgado C, Suárez-Pereira I, Bravo L, Mariscal P, Garcia-Partida JA, López-Martín C, Wei H, Pertovaara A, Mico JA, Berrocoso E. Pain and depression comorbidity causes asymmetric plasticity in the locus coeruleus neurons. Brain 2021; 145:154-167. [PMID: 34373893 PMCID: PMC8967092 DOI: 10.1093/brain/awab239] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 06/12/2021] [Accepted: 06/17/2021] [Indexed: 11/13/2022] Open
Abstract
There is strong comorbidity between chronic pain and depression, although the neural circuits and mechanisms underlying this association remain unclear. By combining immunohistochemistry, tracing studies and western-blotting, with the use of different DREADDs (Designer Receptor Exclusively Activated by Designer Drugs) and behavioural approaches in a rat model of neuropathic pain (chronic constriction injury), we explore how this comorbidity arises. To this end, we evaluated the time-dependent plasticity of noradrenergic-locus coeruleus (LC) neurons relative to the site of injury: ipsilateral (LCipsi) or contralateral (LCcontra) at three different time points: short- (2 days), mid- (7 days), and long-term (30-35 days from nerve injury). Nerve injury led to sensorial hypersensitivity from the onset of injury, whereas depressive-like behavior was only evident following long-term pain. Global chemogenetic blockade of the LCipsi system alone increased short-term pain sensitivity while the blockade of the LCipsi or LCcontra relieved pain-induced depression. The asymmetric contribution of LC-modules was also evident as neuropathy develops. Hence, chemogenetic blockade of the LCipsi→spinal cord projection, increased pain-related behaviours in the short-term. However, this lateralized circuit is not universal as the bilateral chemogenetic inactivation of the LC-rostral anterior cingulate cortex (rACC) pathway or the intra-rACC antagonism of alpha1- and alpha2-adrenoreceptors reversed long-term pain-induced depression. Furthermore, chemogenetic LC to spinal cord activation, mainly through LCipsi, reduced sensorial hypersensitivity irrespective of the time post-injury. Our results indicate that asymmetric activation of specific LC modules promotes early restorative-analgesia, as well as late depressive-like behavior in chronic pain and depression comorbidity.
Collapse
Affiliation(s)
- Meritxell Llorca-Torralba
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Cádiz, Spain.,Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain.,Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Carmen Camarena-Delgado
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Cádiz, Spain.,Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
| | - Irene Suárez-Pereira
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain.,Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain.,Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, Cádiz, Spain
| | - Lidia Bravo
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain.,Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain.,Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, Cádiz, Spain
| | - Patricia Mariscal
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain.,Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, Cádiz, Spain
| | - Jose Antonio Garcia-Partida
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain.,Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, Cádiz, Spain
| | - Carolina López-Martín
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Cádiz, Spain.,Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
| | - Hong Wei
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Antti Pertovaara
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Juan Antonio Mico
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain.,Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain.,Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, Cádiz, Spain
| | - Esther Berrocoso
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Cádiz, Spain.,Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain.,Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| |
Collapse
|
16
|
Cui D, Li ZH, Li C, Qiu C, Ma P, Wu M, Song XJ. Spinal beta-amyloid1-42 acts as an endogenous analgesic peptide in CCI-induced neuropathic pain. Eur J Pain 2021; 26:133-142. [PMID: 34288242 DOI: 10.1002/ejp.1843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND The mechanism for reduced pain sensitivity associated with Alzheimer's disease (AD) has not been illustrated. We hypothesize that amyloid beta 1-42 (Aβ1-42) in the spinal cord acts as an endogenous analgesic peptide to suppress pain induced by nerve injury. METHODS We used chronic constriction injury of the sciatic nerve (CCI) to produce neuropathic pain in Sprague-Dawley rats. Enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry were used to determine the level of Aβ1-42, the expression of Wnt3a/5b and glial activation in the spinal cord. Western blotting was used to determine the expression of interleukins, the phosphorylation of NR2B and ERK1/2, and the nuclear accumulation of transcriptional factors YAP/TAZ. Thermal hyperalgesia and mechanical allodynia were assessed after CCI and pharmacological manipulations through intrathecal administration. RESULTS Nerve injury increases spinal level of Aβ1-42, while intrathecal administration of MK-8931 reduces the level of Aβ1-42 and facilitates mechanical allodynia. Intrathecal administration of Aβ1-42 suppresses pain behaviors in the early and late phases of neuropathy. Spinal administration of Aβ1-42 regulates the expression of interleukins, reducing glial activation and phosphorylation of NR2B and ERK1/2 in the spinal cord of CCI rats. Furthermore, intrathecal administration of Aβ1-42 decreases Wnt5b expression and suppresses the nuclear accumulation of YAP and TAZ. Blocking the interaction between Aβ1-42 and Frizzled receptors by cSP5 reverses the analgesic effects of Aβ1-42. CONCLUSIONS These findings suggest that spinal Aβ1-42 acts as an endogenous analgesic peptide through regulating cytokines and Wnt pathways. This study may provide a potential target for the development of novel analgesic peptides. SIGNIFICANCE This study provides an explanation of reduced pain sensitivity associated with Alzheimer's disease. Furthermore, our findings propose a possible physiological function of beta-amyloid1-42 to regulate pain. This study may provide a potential target for the development of novel analgesics based on an existing endogenous peptide.
Collapse
Affiliation(s)
- Dong Cui
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education of China), Peking University Cancer Hospital & Institute, Beijing, China.,SUSTech Center for Pain Medicine, Southern University of Science and Technology School of Medicine, Shenzhen, China
| | - Ze-Hua Li
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education of China), Peking University Cancer Hospital & Institute, Beijing, China.,SUSTech Center for Pain Medicine, Southern University of Science and Technology School of Medicine, Shenzhen, China
| | - Cheng Li
- SUSTech Center for Pain Medicine, Southern University of Science and Technology School of Medicine, Shenzhen, China
| | - Chengjie Qiu
- SUSTech Center for Pain Medicine, Southern University of Science and Technology School of Medicine, Shenzhen, China
| | - Pingchuan Ma
- SUSTech Center for Pain Medicine, Southern University of Science and Technology School of Medicine, Shenzhen, China
| | - Mingzheng Wu
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
| | - Xue-Jun Song
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education of China), Peking University Cancer Hospital & Institute, Beijing, China.,SUSTech Center for Pain Medicine, Southern University of Science and Technology School of Medicine, Shenzhen, China
| |
Collapse
|
17
|
Cardenas A, Papadogiannis A, Dimitrov E. The role of medial prefrontal cortex projections to locus ceruleus in mediating the sex differences in behavior in mice with inflammatory pain. FASEB J 2021; 35:e21747. [PMID: 34151467 DOI: 10.1096/fj.202100319rr] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 05/27/2021] [Accepted: 06/07/2021] [Indexed: 11/11/2022]
Abstract
We tested the hypothesis that the cognitive impairment associated with inflammatory pain may result from dysregulation of the top-down control of locus ceruleus's (LC) activity by the medial prefrontal cortex (mPFC). Injection of complete Freund's adjuvant (CFA) served as a model for inflammatory pain. The CFA injection decreased the thermal thresholds in both sexes but only the male mice showed increased anxiety-like behavior and diminished cognition, while the females were not affected. Increased calcium fluorescence, a marker for neuronal activity, was detected by photometry in the mPFC of males but not in females with CFA. Next, while chemogenetic inhibition of the projections from the mPFC to the LC improved the object recognition memory of males with pain, the inhibition of the mPFC to LC pathway in female mice produced anxiolysis and spatial memory deficits. The behavior results prompted us to compare the reciprocal innervation of mPFC and LC between the sexes. We used an anterograde transsynaptic tagging technique, which relies on postsynaptic cre transfer, to assess the innervation of LC by mPFC efferents. The males showed a higher rate of postsynaptic cre transfer into LC neurons from mPFC efferents than the females. And vice versa, a retrograde tracing experiment demonstrated that LC to mPFC projection neurons were more numerous in females when compared to males. In conclusion, we provide evidence that subtle differences in the reciprocal neuronal circuit between the LC and mPFC may contribute to sex differences associated with the adverse cognitive effects of inflammatory pain.
Collapse
Affiliation(s)
- Andrea Cardenas
- Center for the Neurobiology of Stress Resilience and Psychiatric Disorders, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
| | - Alexander Papadogiannis
- Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
| | - Eugene Dimitrov
- Center for the Neurobiology of Stress Resilience and Psychiatric Disorders, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
| |
Collapse
|
18
|
Tavares I, Costa-Pereira JT, Martins I. Monoaminergic and Opioidergic Modulation of Brainstem Circuits: New Insights Into the Clinical Challenges of Pain Treatment? FRONTIERS IN PAIN RESEARCH 2021; 2:696515. [PMID: 35295506 PMCID: PMC8915776 DOI: 10.3389/fpain.2021.696515] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 06/08/2021] [Indexed: 12/22/2022] Open
Abstract
The treatment of neuropathic pain remains a clinical challenge. Analgesic drugs and antidepressants are frequently ineffective, and opioids may induce side effects, including hyperalgesia. Recent results on brainstem pain modulatory circuits may explain those clinical challenges. The dual action of noradrenergic (NA) modulation was demonstrated in animal models of neuropathic pain. Besides the well-established antinociception due to spinal effects, the NA system may induce pronociception by directly acting on brainstem pain modulatory circuits, namely, at the locus coeruleus (LC) and medullary dorsal reticular nucleus (DRt). The serotoninergic system also has a dual action depending on the targeted spinal receptor, with an exacerbated activity of the excitatory 5-hydroxytryptamine 3 (5-HT3) receptors in neuropathic pain models. Opioids are involved in the modulation of descending modulatory circuits. During neuropathic pain, the opioidergic modulation of brainstem pain control areas is altered, with the release of enhanced local opioids along with reduced expression and desensitization of μ-opioid receptors (MOR). In the DRt, the installation of neuropathic pain increases the levels of enkephalins (ENKs) and induces desensitization of MOR, which may enhance descending facilitation (DF) from the DRt and impact the efficacy of exogenous opioids. On the whole, the data discussed in this review indicate the high plasticity of brainstem pain control circuits involving monoaminergic and opioidergic control. The data from studies of these neurochemical systems in neuropathic models indicate the importance of designing drugs that target multiple neurochemical systems, namely, maximizing the antinociceptive effects of antidepressants that inhibit the reuptake of serotonin and noradrenaline and preventing desensitization and tolerance of MOR at the brainstem.
Collapse
Affiliation(s)
- Isaura Tavares
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal
- Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal
- Institute of Investigation and Innovation in Health, University of Porto, Porto, Portugal
- *Correspondence: Isaura Tavares
| | - José Tiago Costa-Pereira
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal
- Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal
- Institute of Investigation and Innovation in Health, University of Porto, Porto, Portugal
- Faculty of Nutrition and Food Science, University of Porto, Porto, Portugal
| | - Isabel Martins
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal
- Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal
- Institute of Investigation and Innovation in Health, University of Porto, Porto, Portugal
| |
Collapse
|
19
|
Santos GX, Barbosa D, de-Souza GG, Kosour C, Parizotto NA, Dos Reis LM. Central involvement of 5-HT1A receptors in antinociception induced by photobiomodulation in animal model of neuropathic pain. Lasers Med Sci 2021; 37:821-829. [PMID: 33890191 DOI: 10.1007/s10103-021-03318-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 04/05/2021] [Indexed: 10/21/2022]
Abstract
This study aimed to investigate the central involvement of 5-HT1A receptors in the nociceptive behavior of mice submitted to the chronic constriction injury (CCI) of sciatic nerve and the subsequent application of photobiomodulation (PBM). Male mice (Swiss-albino) were submitted to CCI and subsequently received an infusion of WAY100635 (5-HT1A receptor antagonist) or intracerebroventricular saline (ICV), followed by infrared laser irradiation (808 nm), in continuous mode, with the power of 100 mW and a dose of 0 J/cm2 (control group) or 50 J/cm2. The thermal hyperalgesia was evaluated by hot plate test, while mechanical allodynia was evaluated by von Frey filaments. After CCI, animals showed a reduction in the nociceptive threshold (p<0.001) when compared to the sham group. In von Frey test, the CCI + saline + PBM 50 J/cm2 group showed an increase in nociceptive threshold (p<0.001) in all measurement moments in comparison with groups CCI + SALINE + PBM 0 J/cm2, CCI + WAY100635 + PBM 50 J/cm2, and CCI + WAY100635 + PBM 0 J/cm2. Similarly, in hot plate test, CCI + SALINE + PBM 50 J/cm2 group showed an increase in nociceptive threshold after application of PBM at 120 and 180 min. Because of the results found, it can be suggested the involvement of 5-HT1A receptors in the central nervous system, since WAY100635 was able to reverse the antinociceptive effect provided by PBM in animals submitted to CCI.
Collapse
Affiliation(s)
| | - Danillo Barbosa
- State University of Midwest Paraná - Unicentro, Guarapuava, PR, Brazil
| | | | - Carolina Kosour
- Physiotherapy Department, Federal University of Alfenas (UNIFAL), Alfenas, Brazil
| | | | - Luciana Maria Dos Reis
- Physiotherapy Department, Federal University of Alfenas (UNIFAL), Alfenas, Brazil.,Physiotherapy Department, Federal University of Paraiba (UFPB), João Pessoa, Brazil
| |
Collapse
|
20
|
Díaz JL, Cuevas F, Pazos G, Álvarez-Bercedo P, Oliva AI, Sarmentero MÁ, Font D, Jiménez-Aquino A, Morón M, Port A, Pascual R, Dordal A, Portillo-Salido E, Reinoso RF, Vela JM, Almansa C. Bicyclic Diazepinones as Dual Ligands of the α2δ-1 Subunit of Voltage-Gated Calcium Channels and the Norepinephrine Transporter. J Med Chem 2021; 64:2167-2185. [PMID: 33591743 DOI: 10.1021/acs.jmedchem.0c01867] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The synthesis and pharmacological activity of a new series of bicyclic diazepinones with dual activity toward the α2δ-1 subunit of voltage-gated calcium channels (Cavα2δ-1) and the norepinephrine transporter (NET) are reported. Exploration of the positions amenable for substitution on a nonaminoacidic Cavα2δ-1 scaffold allowed the identification of favorable positions for the attachment of NET pharmacophores. Among the patterns explored, attachment of the 2-ethylamino-9-methyl-6-phenyl-6,7,8,9-tetrahydro-5H-pyrimido[4,5-e][1,4]diazepin-5-one framework to the meta-position of the phenyl ring of the 3-methylamino-1-phenylpropoxy and 3-methylamino-1-thiophenylpropoxy moieties provided dual compounds with excellent NET functionality. Alternative bicyclic frameworks were also explored, and some lead molecules were identified, which showed a balanced dual profile and exhibited good ADMET properties.
Collapse
Affiliation(s)
- José Luis Díaz
- ESTEVE Pharmaceuticals, Torre Esteve, Passeig de la Zona Franca, 109, 08038 Barcelona, Spain
| | - Félix Cuevas
- Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Gonzalo Pazos
- Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Paula Álvarez-Bercedo
- Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Ana I Oliva
- Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - M Ángeles Sarmentero
- Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Daniel Font
- Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Agustín Jiménez-Aquino
- Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - María Morón
- Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Adriana Port
- ESTEVE Pharmaceuticals, Torre Esteve, Passeig de la Zona Franca, 109, 08038 Barcelona, Spain
| | - Rosalía Pascual
- ESTEVE Pharmaceuticals, Torre Esteve, Passeig de la Zona Franca, 109, 08038 Barcelona, Spain
| | - Albert Dordal
- ESTEVE Pharmaceuticals, Torre Esteve, Passeig de la Zona Franca, 109, 08038 Barcelona, Spain
| | - Enrique Portillo-Salido
- ESTEVE Pharmaceuticals, Torre Esteve, Passeig de la Zona Franca, 109, 08038 Barcelona, Spain
| | - Raquel F Reinoso
- ESTEVE Pharmaceuticals, Torre Esteve, Passeig de la Zona Franca, 109, 08038 Barcelona, Spain
| | - José Miguel Vela
- ESTEVE Pharmaceuticals, Torre Esteve, Passeig de la Zona Franca, 109, 08038 Barcelona, Spain
| | - Carmen Almansa
- ESTEVE Pharmaceuticals, Torre Esteve, Passeig de la Zona Franca, 109, 08038 Barcelona, Spain
| |
Collapse
|
21
|
Drake RAR, Steel KA, Apps R, Lumb BM, Pickering AE. Loss of cortical control over the descending pain modulatory system determines the development of the neuropathic pain state in rats. eLife 2021; 10:e65156. [PMID: 33555256 PMCID: PMC7895525 DOI: 10.7554/elife.65156] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 02/07/2021] [Indexed: 12/21/2022] Open
Abstract
The loss of descending inhibitory control is thought critical to the development of chronic pain but what causes this loss in function is not well understood. We have investigated the dynamic contribution of prelimbic cortical neuronal projections to the periaqueductal grey (PrL-P) to the development of neuropathic pain in rats using combined opto- and chemogenetic approaches. We found PrL-P neurons to exert a tonic inhibitory control on thermal withdrawal thresholds in uninjured animals. Following nerve injury, ongoing activity in PrL-P neurons masked latent hypersensitivity and improved affective state. However, this function is lost as the development of sensory hypersensitivity emerges. Despite this loss of tonic control, opto-activation of PrL-P neurons at late post-injury timepoints could restore the anti-allodynic effects by inhibition of spinal nociceptive processing. We suggest that the loss of cortical drive to the descending pain modulatory system underpins the expression of neuropathic sensitisation after nerve injury.
Collapse
Affiliation(s)
- Robert AR Drake
- School of Physiology, Pharmacology & Neuroscience, University of BristolBristolUnited Kingdom
| | - Kenneth A Steel
- School of Biosciences, University of CardiffCardiffUnited States
| | - Richard Apps
- School of Physiology, Pharmacology & Neuroscience, University of BristolBristolUnited Kingdom
| | - Bridget M Lumb
- School of Physiology, Pharmacology & Neuroscience, University of BristolBristolUnited Kingdom
| | - Anthony E Pickering
- School of Physiology, Pharmacology & Neuroscience, University of BristolBristolUnited Kingdom
- Bristol Anaesthesia, Pain & Critical Care Sciences, Bristol Medical School, Bristol Royal InfirmaryBristolUnited Kingdom
| |
Collapse
|
22
|
Khosravi H, Khalilzadeh E, Vafaei Saiah G. Pain-induced aggression and changes in social behavior in mice. Aggress Behav 2021; 47:89-98. [PMID: 32662216 DOI: 10.1002/ab.21912] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 06/10/2020] [Accepted: 06/15/2020] [Indexed: 12/19/2022]
Abstract
The effects of neuropathic, formalin, and acetic acid-induced visceral pain were investigated on the social and aggressive behaviors in the Swiss male mice. Neuropathic pain was induced by tibial nerve transection (TNT). Also, somatic and visceral pain was conducted by intraplantar injection of diluted formalin (1%, 20 μl) and intraperitoneal administration of acetic acid (0.6%, 200 μl), respectively. Fourteen and twenty one days after the TNT surgery, and also, 1 and 7 days following formalin and acetic acid administration, the three-chambered test was used to determine sociability and preference for social novelty and resident/intruder test was used for the evaluation of the aggressive behaviors. In the sociability phase of the three-chambered test, all the three models of pain did not change the animal's sociability. However, in the social novelty preference phase, the animals in pain showed deficits in social novelty preference by a significant increase in the time spent with the familiar mice compared to the control groups. Also, animals in pain significantly showed more aggressive behaviors like biting and clinching and have much less attack latency in comparison to the control groups. Pain-induced changes in the social novelty preference and aggressive behaviors continued in the neuropathic group until the end of the experiment. However, 7 days following the induction of both formalin and visceral pain, animals' social memory, and aggression almost returned to the standard value. These results suggest that long-lasting pain could lead to social memory impairment and increase aggressive behaviors in mice.
Collapse
Affiliation(s)
- Hatef Khosravi
- Division of Physiology, Department of Basic Sciences, Faculty of Veterinary Medicine University of Tabriz Tabriz Iran
| | - Emad Khalilzadeh
- Division of Physiology, Department of Basic Sciences, Faculty of Veterinary Medicine University of Tabriz Tabriz Iran
| | - Gholamreza Vafaei Saiah
- Division of Physiology, Department of Basic Sciences, Faculty of Veterinary Medicine University of Tabriz Tabriz Iran
| |
Collapse
|
23
|
Spinal astrocytes in superficial laminae gate brainstem descending control of mechanosensory hypersensitivity. Nat Neurosci 2020; 23:1376-1387. [DOI: 10.1038/s41593-020-00713-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 08/24/2020] [Indexed: 12/16/2022]
|
24
|
Zheng Y, Zhou Y, Wu Q, Yue J, Ying X, Li S, Lou X, Yang G, Tu W, Zhou K, Jiang S. Effect of electroacupuncture on the expression of P2 × 4, GABAA γ 2 and long-term potentiation in spinal cord of rats with neuropathic pain. Brain Res Bull 2020; 162:1-10. [PMID: 32428626 DOI: 10.1016/j.brainresbull.2020.04.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 03/10/2020] [Accepted: 04/27/2020] [Indexed: 12/19/2022]
Abstract
OBJECTIVE To observe the impacts of electroacupuncture (EA) stimulation at "Zusanli and Kunlun Points" on spinal dorsal horn microglia activation in L5 spinal nerve ligation (SNL) rats and BNDF, P2 × 4 and GABAAγ2, and the changes in spinal dorsal horn synaptic plasticity in model rats. METHODS Adult male SD rats (180-220 g) were selected and randomly divided into 6 groups, including the sham group, the SNL group, the SNL + EA group, the SNL+5-BDBD group, the SNL + EA + 5-BDBD group and the SNL + FEA group. The changes in the Iba-1, BDNF, P2 × 4 and GABAAγ2 in the spinal cord of rats were observed by Western blotting, immunofluorescence, RT-PCR and other techniques; the long-term changes in the potential after the excitatory synapse of the spinal dorsal horn in rats were observed by in vivo electrophysiological technique. RESULTS After 7 days of intervention, the fluorescence intensity (FI) of P2 × 4 and Iba-1 in the SNL + EA group was lower than that in the SNL group and higher than that in the sham group(P < 0.01), but the FI of GABAAγ2 was higher than that in the SNL group(P < 0.01); the expression of Iba-1, BDNF and P2 × 4 proteins in the SNL + EA group, the SNL+5-BDBD group and the SNL + EA + 5-BDBD group was significantly lower than that in the SNL + FEA group(P < 0.05), but the expression of GABAAγ2 protein was higher (P < 0.05); after treatment with EA, the expression levels of Iba-1 mRNA and P2 × 4 mRNA in the SNL + EA group were lower than those in the SNL group(P < 0.01), but the expression levels of GABAAγ2 mRNA were higher (P < 0.01). Meanwhile, long-term potentiation changes could not be induced in the SNL + EA group. CONCLUSION The EA stimulation at "Zusanli" and "Kunlun" points can improve the pain threshold of rats with neuropathic pain (NP), inhibit the excitatory postsynaptic potential (EPSP), and weaken the excitatory transmission efficiency between synapses during NP.
Collapse
Affiliation(s)
- Yuyin Zheng
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ye Zhou
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Qiaoyun Wu
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jingjing Yue
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xinwang Ying
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Sisi Li
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xinfa Lou
- Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Guanhu Yang
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Wenzhan Tu
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China.
| | - Kecheng Zhou
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China.
| | - Songhe Jiang
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China.
| |
Collapse
|
25
|
Attenuation of the Diffuse Noxious Inhibitory Controls in Chronic Joint Inflammatory Pain Is Accompanied by Anxiodepressive-Like Behaviors and Impairment of the Descending Noradrenergic Modulation. Int J Mol Sci 2020; 21:ijms21082973. [PMID: 32340137 PMCID: PMC7215719 DOI: 10.3390/ijms21082973] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/15/2020] [Accepted: 04/21/2020] [Indexed: 12/17/2022] Open
Abstract
The noradrenergic system is paramount for controlling pain and emotions. We aimed at understanding the descending noradrenergic modulatory mechanisms in joint inflammatory pain and its correlation with the diffuse noxious inhibitory controls (DNICs) and with the onset of anxiodepressive behaviours. In the complete Freund’s adjuvant rat model of Monoarthritis, nociceptive behaviors, DNICs, and anxiodepressive-like behaviors were evaluated. Spinal alpha2-adrenergic receptors (a2-AR), dopamine beta-hydroxylase (DBH), and noradrenaline were quantified concomitantly with a2-AR pharmacologic studies. The phosphorylated extracellular signal–regulated kinases 1 and 2 (pERK1/2) were quantified in the Locus coeruleus (LC), amygdala, and anterior cingulate cortex (ACC). DNIC was attenuated at 42 days of monoarthritis while present on days 7 and 28. On day 42, in contrast to day 28, noradrenaline was reduced and DBH labelling was increased. Moreover, spinal a2-AR were potentiated and no changes in a2-AR levels were observed. Additionally, at 42 days, the activation of ERKs1/2 was increased in the LC, ACC, and basolateral amygdala. This was accompanied by anxiety- and depressive-like behaviors, while at 28 days, only anxiety-like behaviors were observed. The data suggest DNIC is attenuated in prolonged chronic joint inflammatory pain, and this is accompanied by impairment of the descending noradrenergic modulation and anxiodepressive-like behaviors.
Collapse
|
26
|
Hughes SW, Ward G, Strutton PH. Anodal transcranial direct current stimulation over the primary motor cortex attenuates capsaicin‐induced dynamic mechanical allodynia and mechanical pain sensitivity in humans. Eur J Pain 2020; 24:1130-1137. [DOI: 10.1002/ejp.1557] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 02/20/2020] [Accepted: 03/04/2020] [Indexed: 12/18/2022]
Affiliation(s)
- Sam W. Hughes
- The Nick Davey Laboratory Faculty of Medicine Imperial College London London UK
| | - Grace Ward
- The Nick Davey Laboratory Faculty of Medicine Imperial College London London UK
| | - Paul H. Strutton
- The Nick Davey Laboratory Faculty of Medicine Imperial College London London UK
| |
Collapse
|
27
|
Costa-Pereira JT, Ribeiro J, Martins I, Tavares I. Role of Spinal Cord α 2-Adrenoreceptors in Noradrenergic Inhibition of Nociceptive Transmission During Chemotherapy-Induced Peripheral Neuropathy. Front Neurosci 2020; 13:1413. [PMID: 32009887 PMCID: PMC6974806 DOI: 10.3389/fnins.2019.01413] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 12/13/2019] [Indexed: 12/14/2022] Open
Abstract
Chemotherapy-induced peripheral neuropathy (CIPN) is a problem during cancer treatment and for cancer survivors but the central mechanisms underlying CIPN remain understudied. This study aims to determine if CIPN is associated with alterations of noradrenergic modulation of nociceptive transmission at the spinal cord. CIPN was induced in male Wistar rats by paclitaxel injections. One month after CIPN induction, the behavioral effects of the administration of reboxetine (noradrenaline reuptake inhibitor), clonidine (agonist of α2-adrenoreceptors; α2–AR) and atipamezole (antagonist of α2–AR) were evaluated using the von Frey and cold plate tests. Furthermore, we measured the expression of the noradrenaline biosynthetic enzyme dopamine-β-hydroxylase (DBH) and of α2–AR in the spinal dorsal horn. Reboxetine and clonidine reversed the behavioral signs of CIPN whereas the opposite occurred with atipamezole. In the 3 pharmacological approaches, a higher effect was detected in mechanical allodynia, the pain modality which is under descending noradrenergic control. DBH expression was increased at the spinal dorsal horn of paclitaxel-injected animals. The enhanced noradrenergic inhibition during CIPN may represent an adaptation of the descending noradrenergic pain control system to the increased arrival of peripheral nociceptive input. A potentiation of the α2–AR mediated antinociception at the spinal cord may represent a therapeutic opportunity to face CIPN.
Collapse
Affiliation(s)
- José Tiago Costa-Pereira
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal.,Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal.,I3S-Institute for Investigation and Innovation in Health, University of Porto, Porto, Portugal
| | - Joana Ribeiro
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal.,Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal.,I3S-Institute for Investigation and Innovation in Health, University of Porto, Porto, Portugal
| | - Isabel Martins
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal.,Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal.,I3S-Institute for Investigation and Innovation in Health, University of Porto, Porto, Portugal
| | - Isaura Tavares
- Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal.,Institute of Molecular and Cell Biology, University of Porto, Porto, Portugal.,I3S-Institute for Investigation and Innovation in Health, University of Porto, Porto, Portugal
| |
Collapse
|
28
|
Ding YQ, Luo H, Qi JG. MHCII-restricted T helper cells: an emerging trigger for chronic tactile allodynia after nerve injuries. J Neuroinflammation 2020; 17:3. [PMID: 31900220 PMCID: PMC6942353 DOI: 10.1186/s12974-019-1684-0] [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: 09/23/2019] [Accepted: 12/19/2019] [Indexed: 02/08/2023] Open
Abstract
Nerve injury-induced chronic pain has been an urgent problem for both public health and clinical practice. While transition to chronic pain is not an inevitable consequence of nerve injuries, the susceptibility/resilience factors and mechanisms for chronic neuropathic pain after nerve injuries still remain unknown. Current preclinical and clinical studies, with certain notable limitations, have shown that major histocompatibility complex class II–restricted T helper (Th) cells is an important trigger for nerve injury-induced chronic tactile allodynia, one of the most prevalent and intractable clinical symptoms of neuropathic pain. Moreover, the precise pathogenic neuroimmune interfaces for Th cells remain controversial, not to mention the detailed pathogenic mechanisms. In this review, depending on the biology of Th cells in a neuroimmunological perspective, we summarize what is currently known about Th cells as a trigger for chronic tactile allodynia after nerve injuries, with a focus on identifying what inconsistencies are evident. Then, we discuss how an interdisciplinary perspective would improve the understanding of Th cells as a trigger for chronic tactile allodynia after nerve injuries. Finally, we hope that the expected new findings in the near future would translate into new therapeutic strategies via targeting Th cells in the context of precision medicine to either prevent or reverse chronic neuropathic tactile allodynia.
Collapse
Affiliation(s)
- You-Quan Ding
- Department of Histology, Embryology and Neurobiology, West China School of Basic Medical Sciences and Forensic Medicine, Sichuan University, No 17, Section 3, South Ren-min road, Chengdu, 610041, Sichuan, China
| | - Han Luo
- Department of Thyroid and Parathyroid Surgery, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jian-Guo Qi
- Department of Histology, Embryology and Neurobiology, West China School of Basic Medical Sciences and Forensic Medicine, Sichuan University, No 17, Section 3, South Ren-min road, Chengdu, 610041, Sichuan, China.
| |
Collapse
|
29
|
Loss of endogenous analgesia leads to delayed recovery from incisional pain in a rat model of chronic neuropathic pain. Brain Res 2020; 1727:146568. [DOI: 10.1016/j.brainres.2019.146568] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 11/14/2019] [Accepted: 11/23/2019] [Indexed: 02/06/2023]
|
30
|
Patel R, Dickenson AH. A study of cortical and brainstem mechanisms of diffuse noxious inhibitory controls in anaesthetised normal and neuropathic rats. Eur J Neurosci 2019; 51:952-962. [PMID: 31518451 PMCID: PMC7079135 DOI: 10.1111/ejn.14576] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 08/26/2019] [Accepted: 09/03/2019] [Indexed: 12/30/2022]
Abstract
Diffuse noxious inhibitory controls (DNIC) are a mechanism of endogenous descending pain modulation and are deficient in a large proportion of chronic pain patients. However, the pathways involved remain only partially determined with several cortical and brainstem structures implicated. This study examined the role of the dorsal reticular nucleus (DRt) and infralimbic (ILC) region of the medial prefrontal cortex in DNIC. In vivo electrophysiology was performed to record from dorsal horn lamina V/VI wide dynamic range neurones with left hind paw receptive fields in anaesthetised sham‐operated and L5/L6 spinal nerve‐ligated (SNL) rats. Evoked neuronal responses were quantified in the presence and absence of a conditioning stimulus (left ear clamp). In sham rats, DNIC were reproducibly recruited by a heterotopically applied conditioning stimulus, an effect that was absent in neuropathic rats. Intra‐DRt naloxone had no effect on spinal neuronal responses to dynamic brush, punctate mechanical, evaporative cooling and heat stimuli in sham and SNL rats. In addition, intra‐DRt naloxone blocked DNIC in sham rats, but had no effect in SNL rats. Intra‐ILC lidocaine had no effect on spinal neuronal responses to dynamic brush, punctate mechanical, evaporative cooling and heat stimuli in sham and SNL rats. However, differential effects were observed in relation to the expression of DNIC; intra‐ILC lidocaine blocked activation of DNIC in sham rats but restored DNIC in SNL rats. These data suggest that the ILC is not directly involved in mediating DNIC but can modulate its activation and that DRt involvement in DNIC requires opioidergic signalling.
Collapse
Affiliation(s)
- Ryan Patel
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK
| | - Anthony H Dickenson
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK
| |
Collapse
|
31
|
Caraci F, Merlo S, Drago F, Caruso G, Parenti C, Sortino MA. Rescue of Noradrenergic System as a Novel Pharmacological Strategy in the Treatment of Chronic Pain: Focus on Microglia Activation. Front Pharmacol 2019; 10:1024. [PMID: 31572196 PMCID: PMC6751320 DOI: 10.3389/fphar.2019.01024] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Accepted: 08/12/2019] [Indexed: 12/11/2022] Open
Abstract
Different types of pain can evolve toward a chronic condition characterized by hyperalgesia and allodynia, with an abnormal response to normal or even innocuous stimuli, respectively. A key role in endogenous analgesia is recognized to descending noradrenergic pathways that originate from the locus coeruleus and project to the dorsal horn of the spinal cord. Impairment of this system is associated with pain chronicization. More recently, activation of glial cells, in particular microglia, toward a pro-inflammatory state has also been implicated in the transition from acute to chronic pain. Both α2- and β2-adrenergic receptors are expressed in microglia, and their activation leads to acquisition of an anti-inflammatory phenotype. This review analyses in more detail the interconnection between descending noradrenergic system and neuroinflammation, focusing on drugs that, by rescuing the noradrenergic control, exert also an anti-inflammatory effect, ultimately leading to analgesia. More specifically, the potential efficacy in the treatment of neuropathic pain of different drugs will be analyzed. On one side, drugs acting as inhibitors of the reuptake of serotonin and noradrenaline, such as duloxetine and venlafaxine, and on the other, tapentadol, inhibitor of the reuptake of noradrenaline, and agonist of the µ-opioid receptor.
Collapse
Affiliation(s)
- Filippo Caraci
- Department of Drug Sciences, Section of Pharmacology and Toxicology, University of Catania, Catania, Italy.,Oasi Research Institute-IRCCS, Troina, Italy
| | - Sara Merlo
- Department of Biomedical and Biotechnological Sciences, Section of Pharmacology, University of Catania, Catania, Italy
| | - Filippo Drago
- Department of Biomedical and Biotechnological Sciences, Section of Pharmacology, University of Catania, Catania, Italy
| | | | - Carmela Parenti
- Department of Drug Sciences, Section of Pharmacology and Toxicology, University of Catania, Catania, Italy
| | - Maria Angela Sortino
- Department of Biomedical and Biotechnological Sciences, Section of Pharmacology, University of Catania, Catania, Italy
| |
Collapse
|
32
|
Abstract
The taste of sucrose is commonly used to provide pain relief in newborn humans and is innately analgesic to neonatal rodents. In adulthood, sucrose remains a strong motivator to feed, even in potentially hazardous circumstances (ie, threat of tissue damage). However, the neurobiological mechanisms of this endogenous reward-pain interaction are unclear. We have developed a simple model of sucrose drinking-induced analgesia in Sprague-Dawley rats (6-10 weeks old) and have undertaken a behavioral and pharmacological characterization using the Hargreaves' test of hind-paw thermal sensitivity. Our results reveal an acute, potent, and robust inhibitory effect of sucrose drinking on thermal nociceptive behaviour that unlike the phenomenon in neonates is independent of endogenous opioid signalling and does not seem to operate through classical descending inhibition of the spinal cord circuitry. Experience of sucrose drinking had a conditioning effect whereby the apparent expectancy of sucrose enabled water alone (in euvolemic animals) to elicit a short-lasting placebo-like analgesia. Sweet taste alone, however, was insufficient to elicit analgesia in adult rats intraorally perfused with sucrose. Instead, the sucrose analgesia phenomenon only appeared after conditioning by oral perfusion in chronically cannulated animals. This sucrose analgesia was completely prevented by systemic dosing of the endocannabinoid CB1 receptor antagonist rimonabant. These results indicate the presence of an endogenous supraspinal analgesic circuit that is recruited by the context of rewarding drinking and is dependent on endocannabinoid signalling. We propose that this hedonic sucrose-drinking model may be useful for further investigation of the supraspinal control of pain by appetite and reward.
Collapse
|
33
|
Huang W, Kabbani N, Brannan TK, Lin MK, Theiss MM, Hamilton JF, Ecklund JM, Conley YP, Vodovotz Y, Brienza D, Wagner AK, Robbins E, Sowa GA, Lipsky RH. Association of a Functional Polymorphism in the CHRFAM7A Gene with Inflammatory Response Mediators and Neuropathic Pain after Spinal Cord Injury. J Neurotrauma 2019; 36:3026-3033. [PMID: 30924722 DOI: 10.1089/neu.2018.6200] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The alpha 7 nicotinic acetylcholine receptor, α7 nAChR, plays a central role in regulating inflammatory responses. Previous studies showed that pharmacological inhibitors of α7nAChR have a pro-inflammatory effect, increasing the circulating levels of cytokines such as tumor necrosis factor alpha (TNFα). This study focused on how genetic polymorphisms of the partially duplicated α7nAChR gene (CHRFAM7A), which is highly expressed in peripheral blood cells, contribute to functional outcome after spinal cord injury (SCI). In a cohort of 27 SCI patients and 25 emergency room consented controls (% F/M: 15/85, 24/76; mean ± SE age: 35 ± 1.38 and 35 ± 2.0 respectively), a panel of circulating cytokines, noradrenergic metabolite (normetanephrine [NMN]) levels, and clinical data were available within the first 7 days post-injury (DPI) up to 90 DPI, and were investigated in the acute/subacute (DPI 1-21) and intermediate (DPI 22-90) temporal periods. Cytokine and NMN plasma levels on different DPI were analyzed as a function of CHRFAM7A genotype. TNFα levels, as a representative of some elevated inflammatory mediators, were nearly threefold higher in individuals carrying the del-2bp variant of the CHRFAM7A gene compared with that in the no-deletion genotype (p = 0.001 analysis of variance [ANOVA]) 3 weeks DPI, and twofold higher than genotype-matched acute/subacute non-SCI injury controls within 7 days DPI. In contrast, NMN levels were initially unchanged, although after 3 weeks, NMN levels were significantly decreased in SCI individuals carrying the del-2bp variant compared with non-carriers (p = 0.011 ANOVA). Numerical pain scores over this same period post-injury were significantly elevated in SCI patients carrying the del-2bp variant relative to non-carriers (p = 0.001 ANOVA). Taken together, these data reveal that pro-inflammatory responses associated with CHRFAM7A gene variation may also be associated with differences in pain experience in patients following SCI, at least during the intermediate phase.
Collapse
Affiliation(s)
- Wan Huang
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Nadine Kabbani
- School of Systems Biology, George Mason University, Fairfax, Virginia
| | - Tricia K Brannan
- Inova Neuroscience Institute, Inova Health System, Falls Church, Virginia
| | - Ming Kuan Lin
- School of Systems Biology, George Mason University, Fairfax, Virginia
| | - Mark M Theiss
- Department of Orthopedic Services, Inova Fairfax Hospital, Falls Church, Virginia
| | - John F Hamilton
- Inova Neuroscience Institute, Inova Health System, Falls Church, Virginia
| | - James M Ecklund
- Inova Neuroscience Institute, Inova Health System, Falls Church, Virginia
| | - Yvette P Conley
- School of Nursing, Pittsburgh, Bioengineering McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Yoram Vodovotz
- Department of Surgery, Center for Inflammation and Regenerative Modeling, Bioengineering McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - David Brienza
- Rehabilitation Science and Technology, Bioengineering McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.,Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Amy K Wagner
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Emily Robbins
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Gwendolyn A Sowa
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.,Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Robert H Lipsky
- School of Systems Biology, George Mason University, Fairfax, Virginia.,Inova Neuroscience Institute, Inova Health System, Falls Church, Virginia
| |
Collapse
|
34
|
Romualdi P, Grilli M, Canonico PL, Collino M, Dickenson AH. Pharmacological rationale for tapentadol therapy: a review of new evidence. J Pain Res 2019; 12:1513-1520. [PMID: 31190962 PMCID: PMC6526917 DOI: 10.2147/jpr.s190160] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Chronic pain could be considered as a neurological disorder. Therefore, appropriate selection of the therapy, which should consider the pathophysiological mechanisms of pain, can result in a successful analgesic outcome. Tapentadol is an analgesic drug which acts both as a μ-opioid receptor (MOR) agonist and as a noradrenaline reuptake inhibitor (NRI), thereby generating a synergistic action in terms of analgesic efficacy, but not for the burden of adverse effects. Therefore, tapentadol can be defined as the first “MOR-NRI” drug. This molecule holds the potential to address at least some of the current limitations of analgesic therapy due to its unique mechanism of action and has shown to be safe and effective in the treatment of chronic pain of cancer and noncancer etiologies including nociceptive, neuropathic and mixed pain. In particular, the MOR component of tapentadol activity predominantly allows for analgesia in nociceptive pain; on the other hand, the NRI component contributes, now in a predominant manner, for analgesic efficacy in cases of neuropathic pain states. This paper will discuss recent pieces of evidence on the pathophysiology of pain, the background on tapentadol and then present some new studies on how the unique mechanism of action of tapentadol provides a key role in its analgesic efficacy in a number of pain states and with a favorable safety profile.
Collapse
Affiliation(s)
- Patrizia Romualdi
- Department of Pharmacy and Biotechnologies Alma Mater Studiorum, University of Bologna, Bologna 40126, Italy
| | - Mariagrazia Grilli
- Laboratory of Neuroplasticity, Department Pharmaceutical Sciences, University of Piemonte Orientale, Novara 28100, Italy
| | - Pier Luigi Canonico
- Departiment of Pharmacological Sciences, University of Piemonte Orientale, Novara 28100, Italy
| | - Massimo Collino
- Department of Drug Science and Technology, University of Turin, Turin 10121, Italy
| | - Anthony H Dickenson
- Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK,
| |
Collapse
|
35
|
Selective deficiencies in descending inhibitory modulation in neuropathic rats: implications for enhancing noradrenergic tone. Pain 2019; 159:1887-1899. [PMID: 29863529 PMCID: PMC6095727 DOI: 10.1097/j.pain.0000000000001300] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Supplemental Digital Content is Available in the Text. Descending noradrenergic pathways modulate spontaneous but not evoked thalamic neuronal hyperexcitability in neuropathic pain states. Spinal clonidine inhibits evoked and spontaneous firing, whereas reboxetine selectively inhibits evoked firing. Pontine noradrenergic neurones form part of a descending inhibitory system that influences spinal nociceptive processing. Weak or absent descending inhibition is a common feature of chronic pain patients. We examined the extent to which the descending noradrenergic system is tonically active, how control of spinal neuronal excitability is integrated into thalamic relays within sensory-discriminative projection pathways, and how this inhibitory control is altered after nerve injury. In vivo electrophysiology was performed in anaesthetised spinal nerve–ligated (SNL) and sham-operated rats to record from wide dynamic range neurones in the ventral posterolateral thalamus (VPL). In sham rats, spinal block of α2-adrenoceptors with atipamezole resulted in enhanced stimulus-evoked and spontaneous firing in the VPL, and produced conditioned place avoidance. However, in SNL rats, these conditioned avoidance behaviours were absent. Furthermore, inhibitory control of evoked neuronal responses was lost, but spinal atipamezole markedly increased spontaneous firing. Augmenting spinal noradrenergic tone in neuropathic rats with reboxetine, a selective noradrenergic reuptake inhibitor, modestly reinstated inhibitory control of evoked responses in the VPL but had no effect on spontaneous firing. By contrast, clonidine, an α2 agonist, inhibited both evoked and spontaneous firing, and exhibited increased potency in SNL rats compared with sham controls. These data suggest descending noradrenergic inhibitory pathways are tonically active in sham rats. Moreover, in neuropathic states, descending inhibitory control is diminished, but not completely absent, and distinguishes between spontaneous and evoked neuronal activity. These observations may have implications for how analgesics targeting the noradrenergic system provide relief.
Collapse
|
36
|
Alles SRA, Smith PA. Comparison of ex vivo and in vitro actions of gabapentin in superficial dorsal horn and the role of extra-spinal sites of drug action. Neurosci Lett 2019; 694:148-153. [PMID: 30500395 DOI: 10.1016/j.neulet.2018.11.050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 11/23/2018] [Accepted: 11/26/2018] [Indexed: 10/27/2022]
Abstract
Although gabapentin (GBP) is a first-line treatment in the management of neuropathic pain, its mechanism of action is incompletely understood. We have previously shown, in rats made neuropathic following sciatic chronic constriction injury, that IP injection of 100 mg/kg GBP decreases overall excitability of spinal cord slices obtained ex vivo. Excitability was assessed using confocal imaging to monitor the amplitude of K+- induced increases in cytoplasmic Ca2+. This decrease in excitability involved a reduction in the frequency and amplitude of spontaneous EPSC's (sEPSC) in putative excitatory substantia gelatinosa neurons and an increase in sEPSC frequency in putative inhibitory neurons. We used have whole-cell recording to compare these ex vivo actions of GBP with its acute in vitro effects on spinal cord slices obtained from neuropathic but drug-free rats. While GBP (100μM) decreased sEPSC amplitude and frequency in excitatory neurons in vitro in a similar fashion to effects observed ex vivo, sEPSC frequency in inhibitory neurons was decreased in vitro rather than increased. Acute in vitro application of GBP also failed to decrease the overall excitability of slices from neuropathic animals as monitored by confocal Ca2+ imaging. Since spinal cord slices in vitro are disconnected from the periphery and higher brain centres, the GBP-induced increase in sEPSC frequency in inhibitory neurons previously reported and seen ex vivo must result from extra-spinal actions. It may be attributable to alterations in descending neurotrophic control of dorsal horn circuitry.
Collapse
Affiliation(s)
- Sascha R A Alles
- Neuroscience and Mental Health Institute and Department of Pharmacology, University of Alberta, Edmonton, AB, T6G 2H7, Canada
| | - Peter A Smith
- Neuroscience and Mental Health Institute and Department of Pharmacology, University of Alberta, Edmonton, AB, T6G 2H7, Canada.
| |
Collapse
|
37
|
Bravo L, Llorca-Torralba M, Berrocoso E, Micó JA. Monoamines as Drug Targets in Chronic Pain: Focusing on Neuropathic Pain. Front Neurosci 2019; 13:1268. [PMID: 31942167 PMCID: PMC6951279 DOI: 10.3389/fnins.2019.01268] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 11/08/2019] [Indexed: 12/11/2022] Open
Abstract
Monoamines are involved in regulating the endogenous pain system and indeed, peripheral and central monoaminergic dysfunction has been demonstrated in certain types of pain, particularly in neuropathic pain. Accordingly, drugs that modulate the monaminergic system and that were originally designed to treat depression are now considered to be first line treatments for certain types of neuropathic pain (e.g., serotonin and noradrenaline (and also dopamine) reuptake inhibitors). The analgesia induced by these drugs seems to be mediated by inhibiting the reuptake of these monoamines, thereby reinforcing the descending inhibitory pain pathways. Hence, it is of particular interest to study the monoaminergic mechanisms involved in the development and maintenance of chronic pain. Other analgesic drugs may also be used in combination with monoamines to facilitate descending pain inhibition (e.g., gabapentinoids and opioids) and such combinations are often also used to alleviate certain types of chronic pain. By contrast, while NSAIDs are thought to influence the monoaminergic system, they just produce consistent analgesia in inflammatory pain. Thus, in this review we will provide preclinical and clinical evidence of the role of monoamines in the modulation of chronic pain, reviewing how this system is implicated in the analgesic mechanism of action of antidepressants, gabapentinoids, atypical opioids, NSAIDs and histaminergic drugs.
Collapse
Affiliation(s)
- Lidia Bravo
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, Cádiz, Spain
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Meritxell Llorca-Torralba
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, Cádiz, Spain
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Esther Berrocoso
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Cádiz, Spain
| | - Juan Antonio Micó
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, Cádiz, Spain
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
- *Correspondence: Juan Antonio Micó,
| |
Collapse
|
38
|
Llorca-Torralba M, Pilar-Cuéllar F, Bravo L, Bruzos-Cidon C, Torrecilla M, Mico JA, Ugedo L, Garro-Martínez E, Berrocoso E. Opioid Activity in the Locus Coeruleus Is Modulated by Chronic Neuropathic Pain. Mol Neurobiol 2018; 56:4135-4150. [PMID: 30284123 DOI: 10.1007/s12035-018-1361-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 09/20/2018] [Indexed: 12/16/2022]
Abstract
Pain affects both sensory and emotional aversive responses, often provoking depression and anxiety-related conditions when it becomes chronic. As the opioid receptors in the locus coeruleus (LC) have been implicated in pain, stress responses, and opioid drug effects, we explored the modifications to LC opioid neurotransmission in a chronic constriction injury (CCI) model of short- and long-term neuropathic pain (7 and 30 days after nerve injury). No significant changes were found after short-term CCI, yet after 30 days, CCI provoked an up-regulation of cAMP (cyclic 5'-adenosine monophosphate), pCREB (phosphorylated cAMP response element binding protein), protein kinase A, tyrosine hydroxylase, and electrical activity in the LC, as well as enhanced c-Fos expression. Acute mu opioid receptor desensitization was more intense in these animals, measured as the decline of the peak current caused by [Met5]-enkephalin and the reduction of forskolin-stimulated cAMP produced in response to DAMGO. Sustained morphine treatment did not markedly modify certain LC parameters in CCI-30d animals, such as [Met5]-enkephalin-induced potassium outward currents or burst activity and c-Fos rebound after naloxone precipitation, which may limit the development of some typical opioid drug-related adaptations. However, other phenomena were impaired by long-term CCI, including the reduction in forskolin-stimulated cAMP accumulation by DAMGO after naloxone precipitation in morphine dependent animals. Overall, this study suggests that long-term CCI leads to changes at the LC level that may contribute to the anxiodepressive phenotype that develops in these animals. Furthermore, opioid drugs produce complex adaptations in the LC in this model of chronic neuropathic pain.
Collapse
Affiliation(s)
- Meritxell Llorca-Torralba
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, 11003, Cádiz, Spain
- Instituto de Investigación e Innovación en Ciencias Biomédicas de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Avda. Ana de Viya, 21, 11009, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Fuencisla Pilar-Cuéllar
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
- Instituto de Biomedicina y Biotecnología de Cantabria, IBBTEC (Universidad de Cantabria, CSIC, SODERCAN), Departamento de Fisiología y Farmacología, Universidad de Cantabria, 39011, Santander, Spain
| | - Lidia Bravo
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, 11003, Cádiz, Spain
- Instituto de Investigación e Innovación en Ciencias Biomédicas de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Avda. Ana de Viya, 21, 11009, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Cristina Bruzos-Cidon
- Department of Pharmacology, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, 48940, Leioa, Spain
| | - María Torrecilla
- Department of Pharmacology, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, 48940, Leioa, Spain
| | - Juan A Mico
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, 11003, Cádiz, Spain
- Instituto de Investigación e Innovación en Ciencias Biomédicas de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Avda. Ana de Viya, 21, 11009, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Luisa Ugedo
- Department of Pharmacology, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, 48940, Leioa, Spain
| | - Emilio Garro-Martínez
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
- Instituto de Biomedicina y Biotecnología de Cantabria, IBBTEC (Universidad de Cantabria, CSIC, SODERCAN), Departamento de Fisiología y Farmacología, Universidad de Cantabria, 39011, Santander, Spain
| | - Esther Berrocoso
- Instituto de Investigación e Innovación en Ciencias Biomédicas de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Avda. Ana de Viya, 21, 11009, Cádiz, Spain.
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain.
- Neuropsychopharmacology and Psychobiology Research Group, Psychobiology Area, Department of Psychology, University of Cádiz, 11510, Cádiz, Spain.
| |
Collapse
|
39
|
Khalilzadeh E, Azarpey F, Hazrati R, Vafaei Saiah G. Evaluation of different classes of histamine H 1 and H 2 receptor antagonist effects on neuropathic nociceptive behavior following tibial nerve transection in rats. Eur J Pharmacol 2018; 834:221-229. [PMID: 30009812 DOI: 10.1016/j.ejphar.2018.07.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 07/02/2018] [Accepted: 07/12/2018] [Indexed: 12/13/2022]
Abstract
It seems that histamine release in the site of neuronal injury could contribute to the neuropathic pain mechanism. In the present study, we investigated the anti-allodynic effects of chronic administration of different classes of histamine H1 and H2 receptor antagonists on neuropathic nociceptive behavior following tibial nerve transection (TNT) in rats. Peripheral neuropathy was induced by TNT surgery. We performed acetone tests (AT) to record cold allodynia, Von Frey tests (VFT) to measure mechanical allodynia, double plate test (DPT) to evaluate thermal place preference/avoidance and open field test (OFT) for evaluation of animal activity. TNT rats showed a significant mechanical and cold allodynia compared to the sham group. Chlorpheniramine (5 and 15 mg/kg, i.p) significantly attenuated cold allodynia and prevented cold plate avoidance behavior and at the dose of 15 mg/kg remarkably decreased mechanical allodynia. Fexofenadine (10 and 30 mg/kg, p.o) significantly attenuated the mechanical allodynia and prevented cold plate avoidance. Ranitidine (5 and 15 mg/kg, i.p) significantly prevented cold plate avoidance behavior and at the dose of 15 mg/kg notably improved mechanical and cold allodynia. Famotidine (1 and 3 mg/kg, p.o) was ineffective on all nociceptive tests. Gabapantin (100 mg/kg, p.o) significantly improved all types of nociceptive behaviors. These results indicate that both blood brain barrier penetrating (chlorpheniramine) and poorly penetrating (fexofenadine) histamine H1 receptor antagonists could improve the neuropathic pain sign, but only the blood brain barrier penetrating histamine H2 receptor antagonist (ranitidine) could produce anti-allodynic effects in the TNT model of neuropathic pain in rats.
Collapse
Affiliation(s)
- Emad Khalilzadeh
- Division of Physiology, Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran.
| | - Farzin Azarpey
- Division of Physiology, Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Reza Hazrati
- Brain Research Center, Laval University, Quebec, Canada
| | - Gholamreza Vafaei Saiah
- Division of Physiology, Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| |
Collapse
|
40
|
|
41
|
Ito S, Suto T, Saito S, Obata H. Repeated Administration of Duloxetine Suppresses Neuropathic Pain by Accumulating Effects of Noradrenaline in the Spinal Cord. Anesth Analg 2018; 126:298-307. [DOI: 10.1213/ane.0000000000002380] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
42
|
Hirschberg S, Li Y, Randall A, Kremer EJ, Pickering AE. Functional dichotomy in spinal- vs prefrontal-projecting locus coeruleus modules splits descending noradrenergic analgesia from ascending aversion and anxiety in rats. eLife 2017; 6:29808. [PMID: 29027903 PMCID: PMC5653237 DOI: 10.7554/elife.29808] [Citation(s) in RCA: 152] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 10/11/2017] [Indexed: 12/12/2022] Open
Abstract
The locus coeruleus (LC) projects throughout the brain and spinal cord and is the major source of central noradrenaline. It remains unclear whether the LC acts functionally as a single global effector or as discrete modules. Specifically, while spinal-projections from LC neurons can exert analgesic actions, it is not known whether they can act independently of ascending LC projections. Using viral vectors taken up at axon terminals, we expressed chemogenetic actuators selectively in LC neurons with spinal (LC:SC) or prefrontal cortex (LC:PFC) projections. Activation of the LC:SC module produced robust, lateralised anti-nociception while activation of LC:PFC produced aversion. In a neuropathic pain model, LC:SC activation reduced hind-limb sensitisation and induced conditioned place preference. By contrast, activation of LC:PFC exacerbated spontaneous pain, produced aversion and increased anxiety-like behaviour. This independent, contrasting modulation of pain-related behaviours mediated by distinct noradrenergic neuronal populations provides evidence for a modular functional organisation of the LC.
Collapse
Affiliation(s)
- Stefan Hirschberg
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom
| | - Yong Li
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom
| | - Andrew Randall
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom.,Medical School, University of Exeter, Exeter, United Kingdom
| | - Eric J Kremer
- IGMM, CNRS, University of Montpellier, Montpellier, France
| | - Anthony E Pickering
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom
| |
Collapse
|
43
|
Andreoli M, Marketkar T, Dimitrov E. Contribution of amygdala CRF neurons to chronic pain. Exp Neurol 2017; 298:1-12. [PMID: 28830762 DOI: 10.1016/j.expneurol.2017.08.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 08/03/2017] [Accepted: 08/18/2017] [Indexed: 12/30/2022]
Abstract
We investigated the role of amygdala corticotropin-releasing factor (CRF) neurons in the perturbations of descending pain inhibition caused by neuropathic pain. Forced swim increased the tail-flick response latency in uninjured mice, a phenomenon known as stress-induced analgesia (SIA) but did not change the tail-flick response latency in mice with neuropathic pain caused by sciatic nerve constriction. Neuropathic pain also increased the expression of CRF in the central amygdala (CeAmy) and ΔFosB in the dorsal horn of the spinal cord. Next, we injected the CeAmy of CRF-cre mice with cre activated AAV-DREADD (Designer Receptors Exclusively Activated by Designer Drugs) vectors. Activation of CRF neurons by DREADD/Gq did not affect the impaired SIA but inhibition of CRF neurons by DREADD/Gi restored SIA and decreased allodynia in mice with neuropathic pain. The possible downstream circuitry involved in the regulation of SIA was investigated by combined injections of retrograde cre-virus (CAV2-cre) into the locus ceruleus (LC) and cre activated AAV-diphtheria toxin (AAV-FLEX-DTX) virus into the CeAmy. The viral injections were followed by a sciatic nerve constriction ipsilateral or contralateral to the injections. Ablation of amygdala projections to the LC on the side of injury but not on the opposite side, completely restored SIA, decreased allodynia and decreased ΔFosB expression in the spinal cord in mice with neuropathic pain. The possible lateralization of SIA impairment to the side of injury was confirmed by an experiment in which unilateral inhibition of the LC decreased SIA even in uninjured mice. The current view in the field of pain research attributes the process of pain chronification to abnormal functioning of descending pain inhibition. Our results demonstrate that the continuous activity of CRF neurons brought about by persistent pain leads to impaired SIA, which is a symptom of dysregulation of descending pain inhibition. Therefore, an over-activation of amygdala CRF neurons is very likely an important contributing factor for pain chronification.
Collapse
Affiliation(s)
- Matthew Andreoli
- Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064, Unites States.
| | - Tanvi Marketkar
- Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064, Unites States.
| | - Eugene Dimitrov
- Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064, Unites States.
| |
Collapse
|
44
|
Martins I, Tavares I. Reticular Formation and Pain: The Past and the Future. Front Neuroanat 2017; 11:51. [PMID: 28725185 PMCID: PMC5497058 DOI: 10.3389/fnana.2017.00051] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 06/19/2017] [Indexed: 01/10/2023] Open
Abstract
The involvement of the reticular formation (RF) in the transmission and modulation of nociceptive information has been extensively studied. The brainstem RF contains several areas which are targeted by spinal cord afferents conveying nociceptive input. The arrival of nociceptive input to the RF may trigger alert reactions which generate a protective/defense reaction to pain. RF neurons located at the medulla oblongata and targeted by ascending nociceptive information are also involved in the control of vital functions that can be affected by pain, namely cardiovascular control. The RF contains centers that belong to the pain modulatory system, namely areas involved in bidirectional balance (decrease or enhancement) of pain responses. It is currently accepted that the imbalance of pain modulation towards pain facilitation accounts for chronic pain. The medullary RF has the peculiarity of harboring areas involved in bidirectional pain control namely by the existence of specific neuronal populations involved in antinociceptive or pronociceptive behavioral responses, namely at the rostroventromedial medulla (RVM) and the caudal ventrolateral medulla (VLM). Furthermore the dorsal reticular nucleus (also known as subnucleus reticularis dorsalis; DRt) may enhance nociceptive responses, through a reverberative circuit established with spinal lamina I neurons and inhibit wide-dynamic range (WDR) neurons of the deep dorsal horn. The components of the triad RVM-VLM-DRt are reciprocally connected and represent a key gateway for top-down pain modulation. The RVM-VLM-DRt triad also represents the neurobiological substrate for the emotional and cognitive modulation of pain, through pathways that involve the periaqueductal gray (PAG)-RVM connection. Collectively, we propose that the RVM-VLM-DRt triad represents a key component of the “dynamic pain connectome” with special features to provide integrated and rapid responses in situations which are life-threatening and involve pain. The new available techniques in neurobiological studies both in animal and human studies are producing new and fascinating data which allow to understand the complex role of the RF in pain modulation and its integration with several body functions and also how the RF accounts for chronic pain.
Collapse
Affiliation(s)
- Isabel Martins
- Departamento de Biomedicina, Faculdade de Medicina do PortoPorto, Portugal.,Unidade de Biologia Experimental, Faculdade de Medicina do Porto, Universidade do PortoPorto, Portugal.,Instituto de Biologia Celular e Molecular (IBMC), Universidade do PortoPorto, Portugal.,Instituto de Investigação e Inovação em Saúde, Universidade do Porto (I3S)Porto, Portugal
| | - Isaura Tavares
- Departamento de Biomedicina, Faculdade de Medicina do PortoPorto, Portugal.,Unidade de Biologia Experimental, Faculdade de Medicina do Porto, Universidade do PortoPorto, Portugal.,Instituto de Biologia Celular e Molecular (IBMC), Universidade do PortoPorto, Portugal.,Instituto de Investigação e Inovação em Saúde, Universidade do Porto (I3S)Porto, Portugal
| |
Collapse
|
45
|
Bannister K, Dickenson AH. The plasticity of descending controls in pain: translational probing. J Physiol 2017; 595:4159-4166. [PMID: 28387936 DOI: 10.1113/jp274165] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 03/15/2017] [Indexed: 01/26/2023] Open
Abstract
Descending controls, comprising pathways that originate in midbrain and brainstem regions and project onto the spinal cord, have long been recognised as key links in the multiple neural networks that interact to produce the overall pain experience. There is clear evidence from preclinical and clinical studies that both peripheral and central sensitisation play important roles in determining the level of pain perceived. Much emphasis has been put on spinal cord mechanisms in central excitability, but it is now becoming clear that spinal hyperexcitability can be regulated by descending pathways from the brain that originate from predominantly noradrenergic and serotonergic systems. One pain can inhibit another. In this respect diffuse noxious inhibitory controls (DNIC) are a unique form of endogenous descending inhibitory pathway since they can be easily evoked and quantified in animals and man. The spinal pharmacology of pathways that subserve DNIC are complicated; in the normal situation these descending controls produce a final inhibitory effect through the actions of noradrenaline at spinal α2 -adrenoceptors, although serotonin, acting on facilitatory spinal 5-HT3 receptors, influences the final expression of DNIC also. These descending pathways are altered in neuropathy and the effects of excess serotonin may now become inhibitory through activation of spinal 5-HT7 receptors. Conditioned pain modulation (CPM) is the human counterpart of DNIC and requires a descending control also. Back and forward translational studies between DNIC and CPM, gauged between bench and bedside, are key for the development of analgesic therapies that exploit descending noradrenergic and serotonergic control pathways.
Collapse
Affiliation(s)
| | - A H Dickenson
- University College London, Gower Street, London, WC1E 6BT, UK
| |
Collapse
|
46
|
Chen M, Hoshino H, Saito S, Yang Y, Obata H. Spinal dopaminergic involvement in the antihyperalgesic effect of antidepressants in a rat model of neuropathic pain. Neurosci Lett 2017; 649:116-123. [PMID: 28416380 DOI: 10.1016/j.neulet.2017.04.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 04/10/2017] [Accepted: 04/10/2017] [Indexed: 10/19/2022]
Abstract
Antidepressants such as tricyclic antidepressants, and serotonin noradrenaline reuptake inhibitors are a first-line treatment for neuropathic pain. Here, we aimed to determine the involvement of the spinal dopaminergic system in the antihyperalgesic effects of antidepressants in a rat model of neuropathic pain induced by spinal nerve ligation (SNL). The right L5 spinal nerve of male Sprague-Dawley rats was ligated under inhalation anesthesia to induce hyperalgesia. Behavioral testing was performed by measuring ipsilateral hindpaw withdrawal thresholds after intraperitoneal injection of amitriptyline, duloxetine, milnacipran, and fluoxetine. D2-like receptors were blocked by intrathecal administration of sulpiride. We also determined the concentrations of dopamine in the spinal cord using microdialysis after injection of antidepressants. The dopamine contents in the spinal dorsal horn were also measured in normal and SNL rats at 2, 3, 4, and 8 weeks after SNL surgery. Intraperitoneal injection of amitriptyline, duloxetine, milnacipran, and fluoxetine (3-30mg/kg) produced antihyperalgesic effects, and prevented by intrathecal pre-injection of sulpiride (30μg). Microdialysis revealed the dopamine levels in the spinal cord were increased after intraperitoneal injection of each antidepressant (10mg/kg). Furthermore, the dopamine content in homogenized spinal cord tissue were increased at 2 weeks after SNL and then subsequently declined. Our results suggest that the effect of antidepressants against neuropathic pain is related to modulation of not only noradrenalin and serotonin but also dopamine levels in the spinal cord.
Collapse
Affiliation(s)
- Mi Chen
- Department of Anesthesiology, Gunma University Graduate School of Medicine, 3-39-22, Showa, Maebashi, Gunma 371-8511, Japan; Department of Anesthesiology, Affiliated Hospital of Guizhou Medical University, #28 Guiyi Road, Guiyang, Guizhou 550004, China
| | - Hajime Hoshino
- Department of Anesthesiology, Gunma University Graduate School of Medicine, 3-39-22, Showa, Maebashi, Gunma 371-8511, Japan; Center for Pain Management, Fukushima Medical University Hospital, #1 Hikarigaoka, Fukushima-city, Fukushima 960-1295, Japan
| | - Shigeru Saito
- Department of Anesthesiology, Gunma University Graduate School of Medicine, 3-39-22, Showa, Maebashi, Gunma 371-8511, Japan
| | - Yang Yang
- Department of Anesthesiology, Gunma University Graduate School of Medicine, 3-39-22, Showa, Maebashi, Gunma 371-8511, Japan; Department of Anesthesiology, Affiliated Hospital of Guizhou Medical University, #28 Guiyi Road, Guiyang, Guizhou 550004, China
| | - Hideaki Obata
- Center for Pain Management, Fukushima Medical University Hospital, #1 Hikarigaoka, Fukushima-city, Fukushima 960-1295, Japan; Department of Anesthesiology, Fukushima Medical University, #1 Hikarigaoka, Fukushima-city, Fukushima 960-1295, Japan.
| |
Collapse
|
47
|
Widespread pain sensitization after partial infraorbital nerve transection in MRL/MPJ mice. Pain 2016; 157:740-749. [PMID: 26588696 DOI: 10.1097/j.pain.0000000000000432] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Clinical studies show that chronic pain can spread to adjacent or even distant body regions in some patients. However, little is known about how this happens. In this study, we found that partial infraorbital nerve transection (p-IONX) in MRL/MPJ mice induced not only marked and long-lasting orofacial thermal hyperalgesia but also thermal hyperalgesia from day 3 postoperatively (PO) and tactile allodynia from day 7 PO in bilateral hind paws. Pain sensitization in the hind paw was negatively correlated with facial thermal hyperalgesia at early but not late stage after p-IONX. After a rapid activation of c-Fos, excitability and excitatory synaptic neurotransmission in lumbar dorsal horn neurons were elevated from day 3 and day 7 PO, respectively. In addition, microglial activation after p-IONX transmitted caudally from the Vc in the medulla to lumber dorsal horn in a time-dependent manner. Inhibition of microglial activation by minocycline at early but not late stage after p-IONX postponed and attenuated pain sensitization in the hind paw. These results indicate that neuropathic pain after p-IONX in MRL/MPJ mice spreads from the orofacial region to distant somatic regions and that a rostral-caudal transmission of central sensitization in the spinal cord is involved in the spreading process of pain hypersensitivity.
Collapse
|
48
|
Pan B, Yu H, Fischer GJ, Kramer JM, Hogan QH. Dorsal Root Ganglionic Field Stimulation Relieves Spontaneous and Induced Neuropathic Pain in Rats. THE JOURNAL OF PAIN 2016; 17:1349-1358. [DOI: 10.1016/j.jpain.2016.09.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 08/23/2016] [Accepted: 09/13/2016] [Indexed: 11/16/2022]
|
49
|
Bravo L, Mico JA, Rey-Brea R, Camarena-Delgado C, Berrocoso E. Effect of DSP4 and desipramine in the sensorial and affective component of neuropathic pain in rats. Prog Neuropsychopharmacol Biol Psychiatry 2016; 70:57-67. [PMID: 27181607 DOI: 10.1016/j.pnpbp.2016.05.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 05/08/2016] [Accepted: 05/09/2016] [Indexed: 12/13/2022]
Abstract
Previous findings suggest that neuropathic pain induces characteristic changes in the noradrenergic system that may modify the sensorial and affective dimensions of pain. We raise the hypothesis that different drugs that manipulate the noradrenergic system can modify specific domains of pain. In the chronic constriction injury (CCI) model of neuropathic pain, the sensorial (von Frey and acetone tests) and the affective (place escape/avoidance paradigm) domains of pain were evaluated in rats 1 and 2weeks after administering the noradrenergic neurotoxin [N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride] (DSP4, 50mg/kg). In other animals, we evaluated the effect of enhancing noradrenergic tone in the 2weeks after injury by administering the antidepressant desipramine (10mg/kg/day, delivered by osmotic minipumps) during this period, a noradrenaline reuptake inhibitor. Moreover, the phosphorylation of the extracellular signal regulated kinases (p-ERK) in the anterior cingulate cortex (ACC) was also assessed. The ACC receives direct inputs from the main noradrenergic nucleus, the locus coeruleus, and ERK activation has been related with the expression of pain-related negative affect. These studies revealed that DSP4 almost depleted noradrenergic axons in the ACC and halved noradrenergic neurons in the locus coeruleus along with a decrease in the affective dimension and an increased of p-ERK in the ACC. However, it did not modify sensorial pain perception. By contrast, desipramine reduced pain hypersensitivity, while completely impeding the reduction of the affective pain dimension and without modifying the amount of p-ERK. Together results suggest that the noradrenergic system may regulate the sensorial and affective sphere of neuropathic pain independently.
Collapse
Affiliation(s)
- Lidia Bravo
- Neuropsychopharmacology & Psychobiology Research Group, University of Cádiz, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, 28007 Madrid, Spain; Psychobiology Area, Department of Psychology, University of Cadiz, Spain
| | - Juan A Mico
- Neuropsychopharmacology & Psychobiology Research Group, University of Cádiz, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, 28007 Madrid, Spain; Department of Neuroscience, University of Cádiz, Spain
| | - Raquel Rey-Brea
- Neuropsychopharmacology & Psychobiology Research Group, University of Cádiz, Spain
| | | | - Esther Berrocoso
- Neuropsychopharmacology & Psychobiology Research Group, University of Cádiz, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, 28007 Madrid, Spain; Psychobiology Area, Department of Psychology, University of Cadiz, Spain.
| |
Collapse
|
50
|
Taylor BK, Westlund KN. The noradrenergic locus coeruleus as a chronic pain generator. J Neurosci Res 2016; 95:1336-1346. [PMID: 27685982 DOI: 10.1002/jnr.23956] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 08/25/2016] [Accepted: 09/07/2016] [Indexed: 12/17/2022]
Abstract
Central noradrenergic centers such as the locus coeruleus (LC) are traditionally viewed as pain inhibitory; however, complex interactions among brainstem pathways and their receptors modulate both inhibition and facilitation of pain. In addition to the well-described role of descending pontospinal pathways that inhibit spinal nociceptive transmission, an emerging body of research now indicates that noradrenergic neurons in the LC and their terminals in the dorsal reticular nucleus (DRt), medial prefrontal cortex (mPFC), spinal dorsal horn, and spinal trigeminal nucleus caudalis participate in the development and maintenance of allodynia and hyperalgesia after nerve injury. With time after injury, we argue that the balance of LC function shifts from pain inhibition to pain facilitation. Thus, the pain-inhibitory actions of antidepressant drugs achieved with elevated noradrenaline concentrations in the dorsal horn may be countered or even superseded by simultaneous activation of supraspinal facilitating systems dependent on α1 -adrenoreceptors in the DRt and mPFC as well as α2 -adrenoreceptors in the LC. Indeed, these opposing actions may account in part for the limited treatment efficacy of tricyclic antidepressants and noradrenaline reuptake inhibitors such as duloxetine for the treatment of chronic pain. We propose that the traditional view of the LC as a pain-inhibitory structure be modified to account for its capacity as a pain facilitator. Future studies are needed to determine the neurobiology of ascending and descending pathways and the pharmacology of receptors underlying LC-mediated pain inhibition and facilitation. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Bradley K Taylor
- Department of Physiology, School of Medicine, University of Kentucky Medical Center, Lexington, Kentucky
| | - Karin N Westlund
- Department of Physiology, School of Medicine, University of Kentucky Medical Center, Lexington, Kentucky
| |
Collapse
|