1
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Craft RM. Pain-suppressed consumption of highly palatable liquid in rats. Behav Pharmacol 2024; 35:263-268. [PMID: 38847464 DOI: 10.1097/fbp.0000000000000783] [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: 07/06/2024]
Abstract
This study determined whether consumption of a highly palatable liquid is a reliable measure of inflammatory pain and antinociception in male and female rats. After a 10-day acquisition period, the impact of intraplantar oil vs. complete Freund adjuvant (CFA) on consumption of vanilla-flavored Ensure was assessed, with a sipper tube height 12 or 19 cm above the floor. CFA significantly decreased Ensure consumption, which completely recovered within 4-7 days to levels in oil-treated controls; neither sex nor sipper tube height significantly influenced Ensure consumption. CFA also significantly suppressed Ensure consumption in rats not exposed to the 10-day acquisition period, but only in males. To test the predictive validity of Ensure consumption as a measure of pain, separate rats were pretreated with a vehicle, an opioid, a nonsteroidal anti-inflammatory drug, or a cannabinoid the day after CFA treatment. Morphine and ibuprofen significantly attenuated CFA-suppressed drinking in at least one sex, and tetrahydrocannabinol did not. Neither ibuprofen nor tetrahydrocannabinol significantly altered drinking in oil-injected, 'pain-free' controls, but morphine increased drinking. These results demonstrate that CFA decreases consumption of a highly palatable liquid regardless of previous exposure (training) to the consumption procedure, but only in males. Although standard analgesics attenuate CFA-suppressed drinking, nonspecific hyperphagic effects can confound the interpretation of results. Thus, consumption of a highly palatable liquid is not an optimal measure for candidate analgesic screening.
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Affiliation(s)
- Rebecca M Craft
- Department of Psychology, Washington State University and Pullman, Washington, USA
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2
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Zumbusch AS, McEachern ELF, Morgan OB, Nickner E, Mogil JS. Normative Preclinical Algesiometry Data on the von Frey and Radiant Heat Paw-Withdrawal Tests: An Analysis of Data from More Than 8,000 Mice Over 20 Years. THE JOURNAL OF PAIN 2024; 25:104468. [PMID: 38219851 DOI: 10.1016/j.jpain.2024.01.333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/18/2023] [Accepted: 01/03/2024] [Indexed: 01/16/2024]
Abstract
The measurement of withdrawal to experimenter-delivered mechanical stimuli (von Frey test) and to heat stimuli (radiant heat paw-withdrawal or Hargreaves' test) applied to the hind paws is ubiquitous in preclinical pain research, but no normative values for the most-common applications of these tests have ever been published. We analyzed a retrospective data set of withdrawal thresholds or latencies in 8,150 mice in which these measures were taken using replicate determinations, before and after injection of inflammatory substances or experimental nerve damage producing pain hypersensitivity, totaling 97,332 measurements. All mice were tested in the same physical laboratory over a 20-year period using similar equipment and procedures. We nonetheless find evidence of large interindividual variability, affected by tester, genotype, mouse sex, tester sex, replicate order, and injury. These factors are discussed, and we believe that these normative data will serve as a useful reference for expected values in preclinical pain testing. PERSPECTIVE: This article presents a retrospective analysis of a large data set of mouse von Frey and radiant heat paw-withdrawal (Hargreaves' test) measurements collected in a single laboratory over 20 years. In addition to serving as a normative guide, sources of variability are identified including genotype, tester, and sex.
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Affiliation(s)
- Alicia S Zumbusch
- Departments of Psychology and Anesthesia, Faculties of Science, Medicine, and Dentistry, Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | - Eleri L F McEachern
- Departments of Psychology and Anesthesia, Faculties of Science, Medicine, and Dentistry, Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | - Oakley B Morgan
- Departments of Psychology and Anesthesia, Faculties of Science, Medicine, and Dentistry, Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | - Elodie Nickner
- Departments of Psychology and Anesthesia, Faculties of Science, Medicine, and Dentistry, Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | - Jeffrey S Mogil
- Departments of Psychology and Anesthesia, Faculties of Science, Medicine, and Dentistry, Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
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3
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Vijayakumar Sreelatha H, Palekkodan H, Fasaludeen A, K. Krishnan L, Abelson KSP. Refinement of the motorised laminectomy-assisted rat spinal cord injury model by analgesic treatment. PLoS One 2024; 19:e0294720. [PMID: 38227583 PMCID: PMC10790998 DOI: 10.1371/journal.pone.0294720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 11/06/2023] [Indexed: 01/18/2024] Open
Abstract
Usage and reporting of analgesia in animal models of spinal cord injury (SCI) have been sparse and requires proper attention. The majority of experimental SCI research uses rats as an animal model. This study aimed to probe into the effects of some commonly used regimens with NSAIDs and opioids on well-being of the rats as well as on the functional outcome of the model. This eight-week study used forty-two female Wistar rats (Crl: WI), randomly and equally divided into 6 treatment groups, viz. I) tramadol (5mg/kg) and buprenorphine (0.05mg/kg); II) carprofen (5mg/kg) and buprenorphine (0.05mg/kg); III) carprofen (5mg/kg); IV) meloxicam (1mg/kg) and buprenorphine (0.05mg/kg); V) meloxicam (1mg/kg); and VI) no analgesia (0.5 ml sterile saline). Buprenorphine was administered twice daily whereas other treatments were given once daily for five days post-operatively. Injections were given subcutaneously. All animals underwent dental burr-assisted laminectomy at the T10-T11 vertebra level. A custom-built calibrated spring-loaded 200 kilodynes force deliverer was used to induce severe SCI. Weekly body weight scores, Rat Grimace Scale (RGS), and dark-phase home cage activity were used as markers for well-being. Weekly Basso Beattie and Bresnahan (BBB) scores served as markers for functionality together with Novel Object Recognition test (NOR) at week 8 and terminal histopathology using area of vacuolisation and live neuronal count from the ventral horns of spinal cord. It was concluded that the usage of analgesia improved animal wellbeing while having no effects on the functional aspects of the animal model in comparison to the animals that received no analgesics.
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Affiliation(s)
- Harikrishnan Vijayakumar Sreelatha
- Department of Applied Biology, Division of Laboratory Animal Science, Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India
- Department of Experimental Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hamza Palekkodan
- Department of Veterinary Pathology, College of Veterinary and Animal Sciences, Pookot, Wayanad, Kerala, India
| | - Ansar Fasaludeen
- Department of Veterinary Pathology, College of Veterinary and Animal Sciences, Pookot, Wayanad, Kerala, India
| | - Lissy K. Krishnan
- Biological Research and Innovation Wing, Dr. Moopen’s Medical College, Wayanad, Kerala, India
| | - Klas S. P. Abelson
- Department of Experimental Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Rivi V, Batabyal A, Benatti C, Blom JMC, Tascedda F, Lukowiak K. Investigating the interactions between multiple memory stores in the pond snail Lymnaea stagnalis. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2024; 210:91-102. [PMID: 37395798 DOI: 10.1007/s00359-023-01649-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 06/01/2023] [Accepted: 06/17/2023] [Indexed: 07/04/2023]
Abstract
The pond snail Lymnaea stagnalis exhibits various forms of associative learning including (1) operant conditioning of aerial respiration where snails are trained not to open their pneumostome in a hypoxic pond water environment using a weak tactile stimulus to their pneumostome as they attempt to open it; and (2) a 24 h-lasting taste-specific learned avoidance known as the Garcia effect utilizing a lipopolysaccharide (LPS) injection just after snails eat a novel food substance (carrot). Typically, lab-inbred snails require two 0.5 h training sessions to form long-term memory (LTM) for operant conditioning of aerial respiration. However, some stressors (e.g., heat shock or predator scent) act as memory enhancers and thus a single 0.5 h training session is sufficient to enhance LTM formation lasting at least 24 h. Here, we found that snails forming a food-aversion LTM following Garcia-effect training exhibited enhanced LTM following operant condition of aerial respiration if trained in the presence of the food substance (carrot) they became averse to. Control experiments led us to conclude that carrot becomes a 'sickness' risk signal and acts as a stressor, sufficient to enhance LTM formation for another conditioning procedure.
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Affiliation(s)
- Veronica Rivi
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy.
| | - Anuradha Batabyal
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Department of Physical and Natural Sciences, FLAME University, Pune, India
| | - Cristina Benatti
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
| | - Johanna M C Blom
- Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Fabio Tascedda
- Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- CIB, Consorzio Interuniversitario Biotecnologie, Trieste, Italy
| | - Ken Lukowiak
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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Caparaso SM, Redwine AL, Wachs RA. Engineering a multicompartment in vitro model for dorsal root ganglia phenotypic assessment. J Biomed Mater Res B Appl Biomater 2023; 111:1903-1920. [PMID: 37326300 PMCID: PMC10527728 DOI: 10.1002/jbm.b.35294] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 05/19/2023] [Accepted: 05/31/2023] [Indexed: 06/17/2023]
Abstract
Despite the significant global prevalence of chronic pain, current methods to identify pain therapeutics often fail translation to the clinic. Phenotypic screening platforms rely on modeling and assessing key pathologies relevant to chronic pain, improving predictive capability. Patients with chronic pain often present with sensitization of primary sensory neurons (that extend from dorsal root ganglia [DRG]). During neuronal sensitization, painful nociceptors display lowered stimulation thresholds. To model neuronal excitability, it is necessary to maintain three key anatomical features of DRGs to have a physiologically relevant platform: (1) isolation between DRG cell bodies and neurons, (2) 3D platform to preserve cell-cell and cell-matrix interactions, and (3) presence of native non-neuronal support cells, including Schwann cells and satellite glial cells. Currently, no culture platforms maintain the three anatomical features of DRGs. Herein, we demonstrate an engineered 3D multicompartment device that isolates DRG cell bodies and neurites and maintains native support cells. We observed neurite growth into isolated compartments from the DRG using two formulations of collagen, hyaluronic acid, and laminin-based hydrogels. Further, we characterized the rheological, gelation and diffusivity properties of the two hydrogel formulations and found the mechanical properties mimic native neuronal tissue. Importantly, we successfully limited fluidic diffusion between the DRG and neurite compartment for up to 72 h, suggesting physiological relevance. Lastly, we developed a platform with the capability of phenotypic assessment of neuronal excitability using calcium imaging. Ultimately, our culture platform can screen neuronal excitability, providing a more translational and predictive system to identify novel pain therapeutics to treat chronic pain.
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Affiliation(s)
- Sydney M. Caparaso
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln Nebraska, USA
| | - Adan L. Redwine
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln Nebraska, USA
| | - Rebecca A. Wachs
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln Nebraska, USA
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6
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Portier K. Unifying two medicines to fight pain and to make anesthesia safer. Front Vet Sci 2023; 10:1248942. [PMID: 37732144 PMCID: PMC10507349 DOI: 10.3389/fvets.2023.1248942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 08/21/2023] [Indexed: 09/22/2023] Open
Affiliation(s)
- Karine Portier
- Université de Lyon, VetAgro Sup, CREFAC, Marcy l'Etoile, France
- Université Claude Bernard Lyon, Centre de Recherche en Neurosciences de Lyon, INSERM, CRNL U1028 UMR5292, Trajectoire, Lyon, Bron, France
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Rivi V, Rigillo G, Toscano Y, Benatti C, Blom JMC. Narrative Review of the Complex Interaction between Pain and Trauma in Children: A Focus on Biological Memory, Preclinical Data, and Epigenetic Processes. CHILDREN (BASEL, SWITZERLAND) 2023; 10:1217. [PMID: 37508714 PMCID: PMC10378710 DOI: 10.3390/children10071217] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 07/07/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023]
Abstract
The incidence and collective impact of early adverse experiences, trauma, and pain continue to increase. This underscores the urgent need for translational efforts between clinical and preclinical research to better understand the underlying mechanisms and develop effective therapeutic approaches. As our understanding of these issues improves from studies in children and adolescents, we can create more precise preclinical models and ultimately translate our findings back to clinical practice. A multidisciplinary approach is essential for addressing the complex and wide-ranging effects of these experiences on individuals and society. This narrative review aims to (1) define pain and trauma experiences in childhood and adolescents, (2) discuss the relationship between pain and trauma, (3) consider the role of biological memory, (4) decipher the relationship between pain and trauma using preclinical data, and (5) examine the role of the environment by introducing the importance of epigenetic processes. The ultimate scope is to better understand the wide-ranging effects of trauma, abuse, and chronic pain on children and adolescents, how they occur, and how to prevent or mitigate their effects and develop effective treatment strategies that address both the underlying causes and the associated physiological and psychological effects.
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Affiliation(s)
- Veronica Rivi
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Giovanna Rigillo
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Ylenia Toscano
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Cristina Benatti
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
- Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Johanna Maria Catharina Blom
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
- Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, 41125 Modena, Italy
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8
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Sadighparvar S, Al-Hamed FS, Sharif-Naeini R, Meloto CB. Preclinical orofacial pain assays and measures and chronic primary orofacial pain research: where we are and where we need to go. FRONTIERS IN PAIN RESEARCH 2023; 4:1150749. [PMID: 37293433 PMCID: PMC10244561 DOI: 10.3389/fpain.2023.1150749] [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: 01/24/2023] [Accepted: 04/11/2023] [Indexed: 06/10/2023] Open
Abstract
Chronic primary orofacial pain (OFP) conditions such as painful temporomandibular disorders (pTMDs; i.e., myofascial pain and arthralgia), idiopathic trigeminal neuralgia (TN), and burning mouth syndrome (BMS) are seemingly idiopathic, but evidence support complex and multifactorial etiology and pathophysiology. Important fragments of this complex array of factors have been identified over the years largely with the help of preclinical studies. However, findings have yet to translate into better pain care for chronic OFP patients. The need to develop preclinical assays that better simulate the etiology, pathophysiology, and clinical symptoms of OFP patients and to assess OFP measures consistent with their clinical symptoms is a challenge that needs to be overcome to support this translation process. In this review, we describe rodent assays and OFP pain measures that can be used in support of chronic primary OFP research, in specific pTMDs, TN, and BMS. We discuss their suitability and limitations considering the current knowledge of the etiology and pathophysiology of these conditions and suggest possible future directions. Our goal is to foster the development of innovative animal models with greater translatability and potential to lead to better care for patients living with chronic primary OFP.
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Affiliation(s)
- Shirin Sadighparvar
- Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada
- The Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
| | | | - Reza Sharif-Naeini
- The Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
- Department of Physiology and Cell Information Systems, McGill University, Montreal, QC, Canada
| | - Carolina Beraldo Meloto
- The Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
- Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
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Cronin SJF, Andrews NA, Latremoliere A. Peripheralized sepiapterin reductase inhibition as a safe analgesic therapy. Front Pharmacol 2023; 14:1173599. [PMID: 37251335 PMCID: PMC10213231 DOI: 10.3389/fphar.2023.1173599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 05/02/2023] [Indexed: 05/31/2023] Open
Abstract
The development of novel analgesics for chronic pain in the last 2 decades has proven virtually intractable, typically failing due to lack of efficacy and dose-limiting side effects. Identified through unbiased gene expression profiling experiments in rats and confirmed by human genome-wide association studies, the role of excessive tetrahydrobiopterin (BH4) in chronic pain has been validated by numerous clinical and preclinical studies. BH4 is an essential cofactor for aromatic amino acid hydroxylases, nitric oxide synthases, and alkylglycerol monooxygenase so a lack of BH4 leads to a range of symptoms in the periphery and central nervous system (CNS). An ideal therapeutic goal therefore would be to block excessive BH4 production, while preventing potential BH4 rundown. In this review, we make the case that sepiapterin reductase (SPR) inhibition restricted to the periphery (i.e., excluded from the spinal cord and brain), is an efficacious and safe target to alleviate chronic pain. First, we describe how different cell types that engage in BH4 overproduction and contribute to pain hypersensitivity, are themselves restricted to peripheral tissues and show their blockade is sufficient to alleviate pain. We discuss the likely safety profile of peripherally restricted SPR inhibition based on human genetic data, the biochemical alternate routes of BH4 production in various tissues and species, and the potential pitfalls to predictive translation when using rodents. Finally, we propose and discuss possible formulation and molecular strategies to achieve peripherally restricted, potent SPR inhibition to treat not only chronic pain but other conditions where excessive BH4 has been demonstrated to be pathological.
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Affiliation(s)
| | - Nick A. Andrews
- The Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Alban Latremoliere
- Departments of Neurosurgery and Neuroscience, Johns Hopkins School of Medicine, Neurosurgery Pain Research Institute, Baltimore, MD, United States
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Jin MY, Everett ES, Abd-Elsayed A. Microbiological and Physiological Effects of Pain. Curr Pain Headache Rep 2023; 27:165-173. [PMID: 37086365 PMCID: PMC10122082 DOI: 10.1007/s11916-023-01114-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/14/2023] [Indexed: 04/23/2023]
Abstract
Pain is an important innate defense mechanism that can dramatically alter a person's quality of life. Understanding the microbiological and physiological effects of pain may be important in the pursuit of novel pain interventions. The three descriptors of pain recognized by the International Association for the Study of Pain are nociceptive, neuropathic, and nociplastic pain. Our review examined the current understanding of all three pain types, focusing on the key molecules involved in the manifestation of each type as well as physiological effects. Additionally, we compared the differences in painful and painless neuropathies and discussed the neuroimmune interaction involved in the manifestation of pain.
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Affiliation(s)
- Max Y Jin
- Department of Anesthesiology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Erin S Everett
- Tulane University School of Medicine, New Orleans, LA, 70112, USA
| | - Alaa Abd-Elsayed
- Department of Anesthesiology, University of Wisconsin-Madison, Madison, WI, 53706, USA.
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11
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Chan KM, Bowe MT, Allen KD. Recommendations for the analysis of rodent gait data to evaluate osteoarthritis treatments. Osteoarthritis Cartilage 2023; 31:425-434. [PMID: 36435413 DOI: 10.1016/j.joca.2022.11.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 10/15/2022] [Accepted: 11/10/2022] [Indexed: 11/26/2022]
Abstract
Behavioral assays of animal pain and disability can increase the clinical relevance of a preclinical study. However, pain and symptoms are difficult to measure in preclinical models. Because animals often alter their movement patterns to reduce or avoid joint pain, gait analysis can be an important tool for quantifying OA-related symptoms in rodents. Technologies to measure rodent gait continue to advance and have been the focus of prior reviews. Regardless of the techniques used, the analysis of rodent gait data can be complex due to multiple confounding variables. The goal of this review is to discuss recent advances in the understanding of OA-related gait changes and provide recommendations on the analysis of gait data. Recent studies suggest OA-affected animals reduce vertical loading through their injured limb while walking, indicating dynamic ground reaction forces are important data to collect when possible. Moreover, gait data analysis depends on accurately measuring and accounting for the confounding effects of velocity and other covariates (such as animal size) when interpreting shifts in various gait parameters. Herein, we discuss different statistical techniques to account for covariates and interpret gait shifts. In particular, this review will discuss residualization and linear mixed effects models, including how both techniques can account for inter- and intra-animal variability and the effects of velocity. Furthermore, this review discusses future considerations for using rodent gait analysis, while highlighting the intricacies of gait analysis as a tool to measure joint function and behavioral outcomes.
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Affiliation(s)
- Kiara M Chan
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Markia T Bowe
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Kyle D Allen
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA; Department of Orthopedics and Sports Medicine, University of Florida, Gainesville, FL, USA.
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12
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Modi AD, Parekh A, Pancholi YN. Evaluating Pain Behaviours: Widely Used Mechanical and Thermal Methods in Rodents. Behav Brain Res 2023; 446:114417. [PMID: 37003494 DOI: 10.1016/j.bbr.2023.114417] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 03/13/2023] [Accepted: 03/29/2023] [Indexed: 04/03/2023]
Abstract
Globally, over 300 million surgical procedures are performed annually, with pain being one of the most common post-operative side effects. During the onset of injury, acute pain plays a protective role in alerting the individual to remove noxious stimuli, while long-lasting chronic pain without any physiological reason is detrimental to the recovery process. Hence, it created an urgent need to better understand the pain mechanism and explore therapeutic targets. Despite the hardship in performing human pain studies due to ethical considerations, clinically relevant rodent pain models provide an excellent opportunity to perform pain studies. Several neurobehavioural tests are used to assess the drug efficacy in rodents to determine avoidance behaviour latency and threshold. This review article provides a methodological overview of mechanical (i.e. von Frey, Mechanical Conflict System) and thermal (i.e. Hargreaves Assay, Hot and Cold Plate, Temperature Place Preference) tests to assess pain in clinically relevant pain rodent models. We further discussed the current modifications of those tests along with their use in literature, the impact of confounding variables, advantages and disadvantages.
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Affiliation(s)
- Akshat D Modi
- Department of Biological Sciences, University of Toronto, Scarborough, Ontario M1C 1A4, Canada; Department of Genetics and Development, Krembil Research Institute, Toronto, Ontario M5T 0S8, Canada.
| | - Anavi Parekh
- Department of Neuroscience, University of Toronto, Toronto, Ontario M5S 1A1, Canada
| | - Yajan N Pancholi
- Department of Neuroscience, University of Toronto, Scarborough, Ontario M1C 1A4, Canada
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13
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Inherited pain hypersensitivity and increased anxiety-like behaviors are associated with genetic epilepsy in Wistar Audiogenic Rats: Short- and long-term effects of acute and chronic seizures on nociception and anxiety. Epilepsy Behav 2023; 141:109160. [PMID: 36907082 DOI: 10.1016/j.yebeh.2023.109160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/14/2023]
Abstract
Anxiety and pain hypersensitivity are neurobehavioral comorbidities commonly reported by patients with epilepsies, and preclinical models are suitable to investigate the neurobiology of behavioral and neuropathological alterations associated with these epilepsy-related comorbidities. This work aimed to characterize endogenous alterations in nociceptive threshold and anxiety-like behaviors in the Wistar Audiogenic Rat (WAR) model of genetic epilepsy. We also assessed the effects of acute and chronic seizures on anxiety and nociception. WARs from acute and chronic seizure protocols were divided into two groups to assess short- and long-term changes in anxiety (1 day or 15 days after seizures, respectively). To assess anxiety-like behaviors, the laboratory animals were submitted to the open field, light-dark box, and elevated plus maze tests. The von Frey, acetone, and hot plate tests were used to measure the endogenous nociception in seizure-free WARs, and postictal antinociception was recorded at 10, 30, 60, 120, 180 min, and 24 h after seizures. Seizure-free WARs presented increased anxiety-like behaviors and pain hypersensitivity, displaying mechanical and thermal allodynia (to heat and cold stimuli) in comparison to nonepileptic Wistar rats. Potent postictal antinociception that persisted for 120 to 180 min was detected after acute and chronic seizures. Additionally, acute and chronic seizures have magnified the expression of anxiety-like behaviors when assessed at 1 day and 15 days after seizures. Behavioral analysis indicated more severe and persistent anxiogenic-like alterations in WARs submitted to acute seizures. Therefore, WARs presented pain hypersensitivity and increased anxiety-like behaviors endogenously associated with genetic epilepsy. Acute and chronic seizures induced postictal antinociception in response to mechanical and thermal stimuli and increased anxiety-like behaviors when assessed 1 day and 15 days later. These findings support the presence of neurobehavioral alterations in subjects with epilepsy and shed light on the use of genetic models to characterize neuropathological and behavioral alterations associated with epilepsy.
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14
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Pharmacological Interaction of Quercetin Derivatives of Tilia americana and Clinical Drugs in Experimental Fibromyalgia. Metabolites 2022; 12:metabo12100916. [PMID: 36295818 PMCID: PMC9607183 DOI: 10.3390/metabo12100916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 09/09/2022] [Accepted: 09/12/2022] [Indexed: 11/16/2022] Open
Abstract
Fibromyalgia (FM) is a pain syndrome characterized by chronic widespread pain and CNS comorbidities. Tilia americana var. mexicana is a medicinal species used to treat anxiety, insomnia, and acute or chronic pain. However, its spectrum of analgesic efficacy for dysfunctional pain is unknown. To investigate a possible therapeutic alternative for FM-type pain, an aqueous Tilia extract (TE) and its flavonoid fraction (FF) containing rutin and isoquercitrin were evaluated alone and/or combined with clinical drugs (tramadol—TRA and pramipexol—PRA) using the reserpine-induced FM model in rats. Chromatographic analysis allowed the characterization of flavonoids, while a histological analysis confirmed their presence in the brain. TE (10–100 mg/kg, i.p.) and FF (10–300 mg/kg, i.p.) produced significant and dose-dependent antihyperalgesic and antiallodynic effects equivalent to TRA (3–10 mg/kg, i.p.) or PRA (0.01–1 mg/kg, s.c.). Nevertheless, the combination of FF + TRA or FF + PRA resulted in an antagonistic interaction by possible competitive action on the serotonin transporter or µ-opioid and D2 receptors, respectively, according to the in silico analysis. Flavonoids were identified in cerebral regions because of their self-epifluorescence. In conclusion, Tilia possesses potential properties to relieve FM-type pain. However, the consumption of this plant or flavonoids such as quercetin derivatives in combination with analgesic drugs might reduce their individual benefits.
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15
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Mogil JS. The history of pain measurement in humans and animals. FRONTIERS IN PAIN RESEARCH 2022; 3:1031058. [PMID: 36185770 PMCID: PMC9522466 DOI: 10.3389/fpain.2022.1031058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 08/31/2022] [Indexed: 11/29/2022] Open
Abstract
Pain needs to be measured in order to be studied and managed. Pain measurement strategies in both humans and non-human animals have varied widely over the years and continue to evolve. This review describes the historical development of human and animal algesiometry.
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16
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Yoon H, Bak MS, Kim SH, Lee JH, Chung G, Kim SJ, Kim SK. Development of a spontaneous pain indicator based on brain cellular calcium using deep learning. EXPERIMENTAL & MOLECULAR MEDICINE 2022; 54:1179-1187. [PMID: 35982300 PMCID: PMC9385425 DOI: 10.1038/s12276-022-00828-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 05/04/2022] [Accepted: 05/23/2022] [Indexed: 12/04/2022]
Abstract
Chronic pain remains an intractable condition in millions of patients worldwide. Spontaneous ongoing pain is a major clinical problem of chronic pain and is extremely challenging to diagnose and treat compared to stimulus-evoked pain. Although extensive efforts have been made in preclinical studies, there still exists a mismatch in pain type between the animal model and humans (i.e., evoked vs. spontaneous), which obstructs the translation of knowledge from preclinical animal models into objective diagnosis and effective new treatments. Here, we developed a deep learning algorithm, designated AI-bRNN (Average training, Individual test-bidirectional Recurrent Neural Network), to detect spontaneous pain information from brain cellular Ca2+ activity recorded by two-photon microscopy imaging in awake, head-fixed mice. AI-bRNN robustly determines the intensity and time points of spontaneous pain even in chronic pain models and evaluates the efficacy of analgesics in real time. Furthermore, AI-bRNN can be applied to various cell types (neurons and glia), brain areas (cerebral cortex and cerebellum) and forms of somatosensory input (itch and pain), proving its versatile performance. These results suggest that our approach offers a clinically relevant, quantitative, real-time preclinical evaluation platform for pain medicine, thereby accelerating the development of new methods for diagnosing and treating human patients with chronic pain. A microscopy technique coupled with an artificial intelligence (AI) platform could help researchers discover new types of pain-relief medicines. A team from South Korea led by Sun Kwang Kim of Kyung Hee University and Sang Jeong Kim of Seoul National University created a machine-learning algorithm that converts calcium signaling data in the brain, as estimated via imaging on genetically engineered mice, into a measurement of pain intensity. The researchers applied the technique to several mouse models of chronic pain and showed that it accurately captured the analgesic effects of known painkillers. They also extended the system to multiple brain regions, cell types and another brain-controlled sensory process, itch. The researchers propose using the AI-based tool to evaluate candidate anti-pain and anti-itch medicines ahead of human trials.
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Affiliation(s)
- Heera Yoon
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea.,Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Myeong Seong Bak
- Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Seung Ha Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea.,Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea
| | - Ji Hwan Lee
- Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Geehoon Chung
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Sang Jeong Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea. .,Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea.
| | - Sun Kwang Kim
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea. .,Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul, 02447, Republic of Korea.
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17
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Patel S, Mittal R, Sarantopoulos KD, Galor A. Neuropathic ocular surface pain: Emerging drug targets and therapeutic implications. Expert Opin Ther Targets 2022; 26:681-695. [PMID: 36069761 PMCID: PMC9613591 DOI: 10.1080/14728222.2022.2122438] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Accepted: 09/05/2022] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Dysfunction at various levels of the somatosensory system can lead to ocular surface pain with a neuropathic component. Compared to nociceptive pain (due to noxious stimuli at the ocular surface), neuropathic pain tends to be chronic and refractory to therapies, making it an important source of morbidity in the population. An understanding of the options available for neuropathic ocular surface pain, including new and emerging therapies, is thus an important topic. AREAS COVERED This review will examine studies focusing on ocular surface pain, emphasizing those examining patients with a neuropathic component. Attention will be placed toward recent (after 2017) studies that have examined new and emerging therapies for neuropathic ocular surface pain. EXPERT OPINION Several therapies have been studied thus far, and continued research is needed to identify which individuals would benefit from specific therapies. Gaps in our understanding exist, especially with availability of in-clinic diagnostics for neuropathic pain. A focus on improving diagnostic capabilities and researching gene-modulating therapies could help us to provide more specific mechanism-based therapies for patients. In the meantime, continuing to uncover new modalities and examining which are likely to work depending on pain phenotype remains an important short-term goal.
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Affiliation(s)
- Sneh Patel
- University of Miami Miller School of Medicine, Miami, FL, USA
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Rhiya Mittal
- University of Miami Miller School of Medicine, Miami, FL, USA
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Konstantinos D. Sarantopoulos
- Department of Anesthesiology, Perioperative Medicine, and Pain Management, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Anat Galor
- University of Miami Miller School of Medicine, Miami, FL, USA
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
- Surgical services, Miami Veterans Affairs Medical Center, Miami, FL, USA
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18
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Santiago V. Painful Truth: The Need to Re-Center Chronic Pain on the Functional Role of Pain. J Pain Res 2022; 15:497-512. [PMID: 35210849 PMCID: PMC8859280 DOI: 10.2147/jpr.s347780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 01/18/2022] [Indexed: 11/23/2022] Open
Abstract
Pain is undesirable, whether it is a symptom of mild or severe illness or instead indicates disorder in the nervous system’s ability to perceive and process sensory information. Nonetheless, pain is part of the body’s ability to defend itself and promote its own survival—this is its fundamental evolutionary function. This normal expression of pain is not limited to what is considered useful because it alerts us to the initiation of illness. It also applies to pain that continues when illness or noxious stimuli persist. However, the parameters of what is here termed functional pain are not fully understood and are seldom explicitly the focus of research. This paper posits that failure to appreciate the functional role of pain in research has had significant unintended consequences and may be contributing to inconsistent research findings. To that end, the paper describes the misclassification issue at the core of chronic pain research—whether a given pain reflects functional or pathological processes—and discusses research areas where reconsidering the functional role of pain may lead to advancements.
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Affiliation(s)
- Vivian Santiago
- Department of Oral & Maxillofacial Pathology, Radiology & Medicine, New York University College of Dentistry, New York, NY, USA
- Correspondence: Vivian Santiago, Email
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19
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Karmakar V, Mohammad FS, Baeesa SS, Alexiou A, Sivakumar SR, Ashraf GM. Effect of Cliothosa aurivilli on Paclitaxel-induced Peripheral Neuropathy in Experimental Animals. Mol Neurobiol 2022; 59:2232-2245. [PMID: 35064539 DOI: 10.1007/s12035-021-02685-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 12/08/2021] [Indexed: 11/28/2022]
Abstract
Chemotherapy-induced peripheral neuropathy (CIPN) is a serious complication leading to painful episodes of parasthesia and numbness in hands and feet. The present drugs that have been used for symptomatic treatment yield inconclusive results in trials and assorted side effects. Thus, there is a pressing demand for development of therapeutically efficacious strategy to combat CIPN. The present study investigates about the effect of a marine sponge; Cliothosa aurivilli (CA) on paclitaxel (PT)-induced peripheral neuropathy in mice. Peripheral neuropathy was induced by intoxication with chemotherapeutic drug PT (2 mg/kg; i.p.) for 5 days consequently. Subsequent treatment with aqueous extract of CA (100 and 200 mg/kg) and standard drug methylcobalamin (MCA) (5 mg/kg) was done and results compared statistically. Neuropathic pain sensations were assessed using various behavioural and locomotory models and evaluated on 0th, 7th and 14th days. Kinovea software was used for video path-tracking of animals and total distance travelled calculated. The results indicated clear signs of improvement post 10 days of PT intoxication in CA-treated groups when compared PT challenged group. A significant reduction in pain behaviours in mechanical allodynia, cold chemical allodynia and thermal hyperalgesia models, improvement in sensory motor coordination, locomotor activity, and distance travelled in closed field model reveals that CA possesses potential ameliorating effect against PT-induced neuropathic pain symptoms. The extract notably improved the movement of the PT challenged animals which was shown by the video path-tracking software and total distance travelled by those animals.
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Affiliation(s)
- Varnita Karmakar
- Department of Pharmaceutical Sciences, Jharkhand Rai University, Ratu Road, Kamre, Ranchi, Jharkhand, 835222, India
| | - Firdous Sayeed Mohammad
- Department of Pharmacology, Calcutta Institute of Pharmaceutical Technology & AHS, Uluberia, Howrah, 711316, West Bengal, India.
| | - Saleh S Baeesa
- Division of Neurosurgery, College of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Athanasios Alexiou
- Novel Global Community Educational Foundation, Hebersham, Australia.,AFNP Med Austria, Wien, Austria
| | - S R Sivakumar
- Department of Botany, Bharathidasan University, Trichy, 620024, Tamilnadu, India
| | - Ghulam Md Ashraf
- Pre-Clinical Research Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia. .,Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.
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20
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Jonas R, Schmelz M. Sensitization of supra-threshold pain responses-Translational aspects and mechanisms. FRONTIERS IN NETWORK PHYSIOLOGY 2022; 2:1078890. [PMID: 36926107 PMCID: PMC10013001 DOI: 10.3389/fnetp.2022.1078890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 12/05/2022] [Indexed: 12/23/2022]
Abstract
A substantial translational gap in pain research has been reflected by a mismatch of relevant primary pain assessment endpoints in preclinical vs. clinical trials. Since activity-dependent mechanisms may be neglected during reflexive tests, this may add as a confounding factor during preclinical pain assessment. In this perspective, we consider the evidence for a need for supra-threshold pain assessment in the pain research literature. In addition to that, we focus on previous results that may demonstrate an example mechanism, where the detection of neuron-glial interactions on pain seems to be substantially depending on the assessment of pain intensity beyond threshold levels.
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Affiliation(s)
- Robin Jonas
- Department of Translational Pharmacology, Medical School EWL, Bielefeld University, Bielefeld, Germany.,UMCG Pain Center, Department of Anaesthesiology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Martin Schmelz
- Department of Experimental Pain Research, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
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21
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Radulescu A, White FA, Chenu C. What Did We Learn About Fracture Pain from Animal Models? J Pain Res 2022; 15:2845-2856. [PMID: 36124034 PMCID: PMC9482434 DOI: 10.2147/jpr.s361826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 07/01/2022] [Indexed: 11/23/2022] Open
Abstract
Progress in bone fracture repair research has been made possible due to the development of reproducible models of fracture in rodents with more clinically relevant fracture fixation, where there is considerably better assessment of the factors that affect fracture healing and/or novel therapeutics. However, chronic or persistent pain is one of the worst, longest-lasting and most difficult symptoms to manage after fracture repair, and an ongoing challenge remains for animal welfare as limited information exists regarding pain scoring and management in these rodent fracture models. This failure of adequate pre-clinical pain assessment following osteotomy in the rodent population may not only subject the animal to severe pain states but may also affect the outcome of the bone healing study. Animal models to study pain were also mainly developed in rodents, and there is increasing validation of fracture and pain models to quantitatively evaluate fracture pain and to study the factors that generate and maintain fracture pain and develop new therapies for treating fracture pain. This review aims to discuss the different animal models for fracture pain research and characterize what can be learned from using animal models of fracture regarding behavioral pain states and new molecular targets for future management of these behaviors.
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Affiliation(s)
- Andreea Radulescu
- Royal Veterinary College, Department of Comparative Biomedical Sciences, London, NW1 OTU, UK
| | - Fletcher A White
- Department of Anesthesia, Indiana University School of Medicine, Indianapolis, IN, USA
- Richard L. Roudebush Veterans Medical Center, Indianapolis, IN, USA
| | - Chantal Chenu
- Royal Veterinary College, Department of Comparative Biomedical Sciences, London, NW1 OTU, UK
- Correspondence: Chantal Chenu, Royal Veterinary College, Department of Comparative Biological Sciences, Royal College Street, London, NW1 0TU, UK, Tel +44 207 468 5045, Email
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22
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Gao L, Cui S, Huang Z, Cui H, Awad Alahmadi T, Manikandan V. Antinociceptive and anti-inflammatory activities of butein in different nociceptive and inflammatory mice models. Saudi J Biol Sci 2021; 28:7090-7097. [PMID: 34867011 PMCID: PMC8626269 DOI: 10.1016/j.sjbs.2021.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/02/2021] [Accepted: 08/01/2021] [Indexed: 11/26/2022] Open
Abstract
Background Around 30% world population affected by acute and chronic pain due to inflammation and accidental injuries. Pain is a uncomfortable sensation and it reduce the patients’ life quality. Objective The present exploration focuses to explore the beneficial effects of butein on the different chemical and thermal-provoked nociceptive and inflammatory mice models. Methodology The nociception was induced to the Swiss mice using different chemical (formalin, acetic acid, glutamate, and capsaicin) and thermal (hot plate and tail immersion) methods. the mice were supplemented with 10, 15, and 20 mg/kg of butein and respective standard drugs like morphine, diclofenac sodium, and dexamethasone. The anti-inflammatory effects of butein was studied using carrageenan-provoked inflammation in mice. Results The present findings clearly demonstrated that the butein was substantially lessened the different thermal and chemical provoked nociception in mice. The carrageenan-triggered paw edema and inflammatory cell infiltrations were appreciably suppressed by the butein treatment. The TNF-α, IL-1β, and IL-6 levels in the carrageenan-induced mice were effectively depleted by the butein. Conclusion Altogether, the present findings evidenced the potent antinociceptive and anti-inflammatory properties of the butein in different nociceptive mice models.
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Affiliation(s)
- Li Gao
- Department of Anesthesiology, The First Affiliated Hospital of Jiamusi University, Jiamusi, Heilongjiang Province 154002, China
| | - Shasha Cui
- Department of Anesthesiology, Jincheng People's Hospital, Jincheng, Shanxi Province 048000, China
| | - Zhiqiang Huang
- Department of Anesthesiology, Xilingo League Central Hospital, Xilingo league, Inner Mongolia Autonomous Region 026000,China
| | - Hailong Cui
- Department of Anesthesiology, Hohhot Maternal and Child Health Hospital, Hohhot, Inner Mongolia Autonomous Region 010031, China
| | - Tahani Awad Alahmadi
- Department of Pediatrics, College of Medicine and King Khalid University Hospital, King Saud University, Medical City, PO Box-2925, Riyadh 11461, Saudi Arabia
| | - Velu Manikandan
- Division of Biotechnology,College of Environmental and Bioresource Sciences, Jeonbuk National University, Iksan 54596, South Korea
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23
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Falsetta ML, Wood RW, Linder MA, Bonham AD, Honn KV, Maddipati KR, Phipps RP, Haidaris CG, Foster DC. Specialized Pro-resolving Mediators Reduce Pro-nociceptive Inflammatory Mediator Production in Models of Localized Provoked Vulvodynia. THE JOURNAL OF PAIN 2021; 22:1195-1209. [PMID: 33813057 PMCID: PMC8484336 DOI: 10.1016/j.jpain.2021.03.144] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 03/05/2021] [Accepted: 03/24/2021] [Indexed: 12/25/2022]
Abstract
Localized provoked vulvodynia (LPV) is the most common cause of chronic dyspareunia in premenopausal women, characterized by pain with light touch to the vulvar vestibule surrounding the vaginal opening. The devastating impact of LPV includes sexual dysfunction, infertility, depression, and even suicide. Yet, its etiology is unclear. No effective medical therapy exists; surgical removal of the painful vestibule is the last resort. In LPV, the vestibule expresses a unique inflammatory profile with elevated levels of pro-nociceptive proinflammatory mediators prostaglandin E2 (PGE2) and interleukin-6 (IL-6), which are linked to lower mechanical sensitivity thresholds. Specialized pro-resolving mediators (SPMs), lipids produced endogenously within the body, hold promise as an LPV treatment by resolving inflammation without impairing host defense. Ten of 13 commercially available SPMs reduced IL-6 and PGE2 production by vulvar fibroblasts, administered either before or after inflammatory stimulation. Using a murine vulvar pain model, coupling proinflammatory mediator quantification with mechanical sensitivity threshold determination, topical treatment with the SPM, maresin 1, decreased sensitivity and suppressed PGE2 levels. Docosahexaenoic acid, a precursor of maresin 1, was also effective in reducing PGE2 in vulvar fibroblasts and rapidly restored mouse sensitivity thresholds. Overall, SPMs and their precursors may be a safe and efficacious for LPV. Perspective: Vulvodynia, like many pain conditions, is difficult to treat because disease origins are incompletely understood. Here, we applied our knowledge of more recently discovered vulvodynia disease mechanisms to screen novel therapeutics. We identified several specialized pro-resolving mediators as likely potent and safe for treating LPV with potential for broader application.
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Affiliation(s)
- Megan L Falsetta
- Department of Obstetrics and Gynecology, University of Rochester, School of Medicine and Dentistry Rochester, New York; Department of Pharmacology and Physiology, University of Rochester, School of Medicine and Dentistry, Rochester, New York.
| | - Ronald W Wood
- Department of Obstetrics and Gynecology, University of Rochester, School of Medicine and Dentistry Rochester, New York
| | - Mitchell A Linder
- Department of Obstetrics and Gynecology, University of Rochester, School of Medicine and Dentistry Rochester, New York
| | - Adrienne D Bonham
- Department of Obstetrics and Gynecology, University of Rochester, School of Medicine and Dentistry Rochester, New York
| | - Kenneth V Honn
- Department of Pathology, Wayne State University, School of Medicine, Detroit, Michigan
| | - Krishna Rao Maddipati
- Department of Pathology, Wayne State University, School of Medicine, Detroit, Michigan
| | | | - Constantine G Haidaris
- Department of Microbiology and Immunology, University of Rochester, School of Medicine and Dentistry Rochester, New York
| | - David C Foster
- Department of Obstetrics and Gynecology, University of Rochester, School of Medicine and Dentistry Rochester, New York
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24
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Zaki S, Smith MM, Little CB. Pathology-pain relationships in different osteoarthritis animal model phenotypes: it matters what you measure, when you measure, and how you got there. Osteoarthritis Cartilage 2021; 29:1448-1461. [PMID: 34332049 DOI: 10.1016/j.joca.2021.03.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 03/17/2021] [Accepted: 03/31/2021] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine whether osteoarthritis (OA) pain characteristics and mechanistic pathways in pre-clinical models are phenotype-specific. DESIGN Male 11-week-old C57BL6 mice had unilateral medial-meniscal-destabilization (DMM) or antigen-induced-arthritis (AIA), vs sham-surgery/immunised-controls (Sham/Im-CT). Pain behaviour (allodynia, mechanical- and thermal-hyperalgesia, hindlimb static weight-bearing, stride-length) and lumbar dorsal root ganglia (DRG) gene-expression were measured at baseline, day-3, week-1/-2/-4/-8/-16, and pain-behaviour:gene-expression:joint-pathology associations investigated. RESULTS DMM and AIA induced structural OA defined by progressively increasing cartilage erosion, subchondral bone sclerosis and osteophyte size and maturation. All pain-behaviours were modified, with model-specific differences in severity and temporal pattern. Tactile allodynia developed acutely in both models and persisted to week-16. During early-OA (wk4-8) there was; reduced right hindlimb weight-bearing in AIA; thermal-hyperalgesia and reduced stride-length in DMM. During chronic-OA (wk12-16); mechanical-hyperalgesia and reduced right hindlimb weight-bearing were observed in DMM only. There were no associations in either model between different pain-behaviour outcomes. A coordinated DRG-expression profile was observed in sham and Im-CT for all 11 genes tested, but not in AIA and DMM. At wk-16 despite equivalent joint pathology, changes in DRG-expression (Calca, Trpa1, Trpv1, Trpv4) were observed only in DMM. In AIA mechanical-hyperalgesia was associated with Trpv1 (r = -0.79) and Il1b (r = 0.53). In DMM stride-length was associated with Calca, Tac1, Trpv1, Trpv2, Trpv4 and Adamts5 (r = 0.4-0.57). DRG gene-expression change was correlated with subchondral-bone sclerosis in DMM, and cartilage damage in AIA. Positive pain-behaviour:joint-pathology associations were only present in AIA - for synovitis, subchondral-bone resorption, chondrocyte-hypertrophy and cartilage damage. CONCLUSION Pain and peripheral sensory neuronal responses are OA-phenotype-specific with distinct pathology:pain-outcome:molecular-mechanism relationships.
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Affiliation(s)
- S Zaki
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, Australia; Raymond Purves Bone and Joint Research Laboratory, Kolling Institute of Medical Research, Faculty of Medicine and Health, The University of Sydney, at Royal North Shore Hospital, Australia.
| | - M M Smith
- Raymond Purves Bone and Joint Research Laboratory, Kolling Institute of Medical Research, Faculty of Medicine and Health, The University of Sydney, at Royal North Shore Hospital, Australia.
| | - C B Little
- Raymond Purves Bone and Joint Research Laboratory, Kolling Institute of Medical Research, Faculty of Medicine and Health, The University of Sydney, at Royal North Shore Hospital, Australia.
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25
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Segelcke D, Pradier B, Reichl S, Schäfer LC, Pogatzki-Zahn EM. Investigating the Role of Ly6G+ Neutrophils in Incisional and Inflammatory Pain by Multidimensional Pain-Related Behavioral Assessments: Bridging the Translational Gap. FRONTIERS IN PAIN RESEARCH 2021; 2:735838. [PMID: 35295496 PMCID: PMC8915677 DOI: 10.3389/fpain.2021.735838] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Accepted: 08/09/2021] [Indexed: 12/27/2022] Open
Abstract
In recent years, preclinical pain research has failed to develop genuinely new analgesics for clinical use. This fact is reflected by a high number of patients, limited drug efficacy accompanied by side effects, and a long-term opioid intake. Two main aspects have been addressed, which hinder translation: the use of non-relevant pain models and a mismatch between pain-related outcomes in preclinical and clinical studies. Conversely, disease-specific pain models that mirror more closely the clinical situation and multidimensional behavioral outcome measures that objectively and reproducibly assess relevant pain-related symptoms in a preclinical setting could improve translation. Mechanistically, a matter of debate is the role of Ly6G+ neutrophil granulocytes (NGs) for pain. NGs are essential to eliminate pathogens and promote the wound healing process. For this purpose, there is a need to release various pro- and anti-inflammatory mediators, some of which could ameliorate or enhance pain. However, the contribution of NGs to different pain entities is contradictory for reflex-based tests, and completely unknown in the context of non-evoked pain (NEP) and movement-evoked pain (MEP). First, we combined withdrawal reflex-based assays with novel video-based assessments for NEP- and MEP-related behavior in two mouse pain models. The pain models utilized in this study were incision (INC) and pathogen/adjuvant-induced inflammation (CFA), translating well to postsurgical and inflammatory pain entities. Second, we depleted NGs and applied a set of behavioral assessments to investigate the role of NG migration in different pain modalities. Our comprehensive behavioral approach identified pain-related behaviors in mice that resemble (NEP) or differentiate (MEP) behavioral trajectories in comparison to mechanical and heat hypersensitivity, thereby indicating modality-dependent mechanisms. Further, we show that injury-induced accumulation of NGs minimally affects pain-related behaviors in both pain models. In conclusion, we report a novel assessment to detect NEP in mice after unilateral injuries using a more unbiased approach. Additionally, we are capable of detecting an antalgic gait for both pain entities with unique trajectories. The different trajectories between MEP and other pain modalities suggest that the underlying mechanisms differ. We further conclude that NGs play a subordinate role in pain-related behaviors in incisional and inflammatory pain.
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Affiliation(s)
- Daniel Segelcke
- Department for Anesthesiology, Operative Intensive Care and Pain Medicine, University Hospital Muenster, Albert-Schweitzer-Campus 1, Muenster, Germany
| | - Bruno Pradier
- Department for Anesthesiology, Operative Intensive Care and Pain Medicine, University Hospital Muenster, Albert-Schweitzer-Campus 1, Muenster, Germany
| | - Sylvia Reichl
- Department for Anesthesiology, Operative Intensive Care and Pain Medicine, University Hospital Muenster, Albert-Schweitzer-Campus 1, Muenster, Germany
- Department of Anesthesiology, Perioperative Medicine, Paracelsus Medical University, Salzburg, Austria
| | - Lukas C. Schäfer
- Department for Anesthesiology, Operative Intensive Care and Pain Medicine, University Hospital Muenster, Albert-Schweitzer-Campus 1, Muenster, Germany
| | - Esther M. Pogatzki-Zahn
- Department for Anesthesiology, Operative Intensive Care and Pain Medicine, University Hospital Muenster, Albert-Schweitzer-Campus 1, Muenster, Germany
- *Correspondence: Esther M. Pogatzki-Zahn
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26
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Bouali-Benazzouz R, Landry M, Benazzouz A, Fossat P. Neuropathic pain modeling: Focus on synaptic and ion channel mechanisms. Prog Neurobiol 2021; 201:102030. [PMID: 33711402 DOI: 10.1016/j.pneurobio.2021.102030] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 02/22/2021] [Indexed: 12/28/2022]
Abstract
Animal models of pain consist of modeling a pain-like state and measuring the consequent behavior. The first animal models of neuropathic pain (NP) were developed in rodents with a total lesion of the sciatic nerve. Later, other models targeting central or peripheral branches of nerves were developed to identify novel mechanisms that contribute to persistent pain conditions in NP. Objective assessment of pain in these different animal models represents a significant challenge for pre-clinical research. Multiple behavioral approaches are used to investigate and to validate pain phenotypes including withdrawal reflex to evoked stimuli, vocalizations, spontaneous pain, but also emotional and affective behaviors. Furthermore, animal models were very useful in investigating the mechanisms of NP. This review will focus on a detailed description of rodent models of NP and provide an overview of the assessment of the sensory and emotional components of pain. A detailed inventory will be made to examine spinal mechanisms involved in NP-induced hyperexcitability and underlying the current pharmacological approaches used in clinics with the possibility to present new avenues for future treatment. The success of pre-clinical studies in this area of research depends on the choice of the relevant model and the appropriate test based on the objectives of the study.
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Affiliation(s)
- Rabia Bouali-Benazzouz
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France.
| | - Marc Landry
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
| | - Abdelhamid Benazzouz
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
| | - Pascal Fossat
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
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27
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Borges JP, Mekhail K, Fairn GD, Antonescu CN, Steinberg BE. Modulation of Pathological Pain by Epidermal Growth Factor Receptor. Front Pharmacol 2021; 12:642820. [PMID: 34054523 PMCID: PMC8149758 DOI: 10.3389/fphar.2021.642820] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 04/26/2021] [Indexed: 12/18/2022] Open
Abstract
Chronic pain has been widely recognized as a major public health problem that impacts multiple aspects of patient quality of life. Unfortunately, chronic pain is often resistant to conventional analgesics, which are further limited by their various side effects. New therapeutic strategies and targets are needed to better serve the millions of people suffering from this devastating disease. To this end, recent clinical and preclinical studies have implicated the epidermal growth factor receptor signaling pathway in chronic pain states. EGFR is one of four members of the ErbB family of receptor tyrosine kinases that have key roles in development and the progression of many cancers. EGFR functions by activating many intracellular signaling pathways following binding of various ligands to the receptor. Several of these signaling pathways, such as phosphatidylinositol 3-kinase, are known mediators of pain. EGFR inhibitors are known for their use as cancer therapeutics but given recent evidence in pilot clinical and preclinical investigations, may have clinical use for treating chronic pain. Here, we review the clinical and preclinical evidence implicating EGFR in pathological pain states and provide an overview of EGFR signaling highlighting how EGFR and its ligands drive pain hypersensitivity and interact with important pain pathways such as the opioid system.
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Affiliation(s)
- Jazlyn P Borges
- Neurosciences and Mental Health Program, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Katrina Mekhail
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Gregory D Fairn
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Department of Surgery, University of Toronto, Toronto, ON, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.,Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada
| | - Costin N Antonescu
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada
| | - Benjamin E Steinberg
- Neurosciences and Mental Health Program, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada.,Department of Anesthesia and Pain Medicine, The Hospital for Sick Children, Toronto, ON, Canada
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28
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Zhang H, Lecker I, Collymore C, Dokova A, Pham MC, Rosen SF, Crawhall-Duk H, Zain M, Valencia M, Filippini HF, Li J, D'Souza AJ, Cho C, Michailidis V, Whissell PD, Patel I, Steenland HW, Virginia Lee WJ, Moayedi M, Sterley TL, Bains JS, Stratton JA, Matyas JR, Biernaskie J, Dubins D, Vukobradovic I, Bezginov A, Flenniken AM, Martin LJ, Mogil JS, Bonin RP. Cage-lid hanging behavior as a translationally relevant measure of pain in mice. Pain 2021; 162:1416-1425. [PMID: 33230005 PMCID: PMC8054539 DOI: 10.1097/j.pain.0000000000002127] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 10/05/2020] [Accepted: 10/21/2020] [Indexed: 12/18/2022]
Abstract
ABSTRACT The development of new analgesic drugs has been hampered by the inability to translate preclinical findings to humans. This failure is due in part to the weak connection between commonly used pain outcome measures in rodents and the clinical symptoms of chronic pain. Most rodent studies rely on the use of experimenter-evoked measures of pain and assess behavior under ethologically unnatural conditions, which limits the translational potential of preclinical research. Here, we addressed this problem by conducting an unbiased, prospective study of behavioral changes in mice within a natural homecage environment using conventional preclinical pain assays. Unexpectedly, we observed that cage-lid hanging, a species-specific elective behavior, was the only homecage behavior reliably impacted by pain assays. Noxious stimuli reduced hanging behavior in an intensity-dependent manner, and the reduction in hanging could be restored by analgesics. Finally, we developed an automated approach to assess hanging behavior. Collectively, our results indicate that the depression of hanging behavior is a novel, ethologically valid, and translationally relevant pain outcome measure in mice that could facilitate the study of pain and analgesic development.
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Affiliation(s)
- Hantao Zhang
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
| | - Irene Lecker
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
| | - Chereen Collymore
- Division of Comparative Medicine, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Animal Care and Veterinary Services, University of Ottawa, Ottawa, ON, Canada
| | - Anastassia Dokova
- Departments of Psychology and Anesthesia, McGill University, Montreal, QC, Canada
| | | | - Sarah F. Rosen
- Departments of Psychology and Anesthesia, McGill University, Montreal, QC, Canada
| | - Hayley Crawhall-Duk
- Departments of Psychology and Anesthesia, McGill University, Montreal, QC, Canada
| | - Maham Zain
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
| | - Megan Valencia
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
| | | | - Jerry Li
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
| | - Abigail J. D'Souza
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
- The Centre for Phenogenomics, Toronto, ON, Canada
| | - Chulmin Cho
- Department of Psychology, University of Toronto at Mississauga, Mississauga, ON, Canada
| | - Vassilia Michailidis
- Department of Psychology, University of Toronto at Mississauga, Mississauga, ON, Canada
| | - Paul D. Whissell
- Cell and Systems Biology, University of Toronto Toronto, ON, Canada
| | - Ingita Patel
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
| | | | - Wai-Jane Virginia Lee
- Centre for Multimodal Sensorimotor and Pain Research, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - Massieh Moayedi
- Centre for Multimodal Sensorimotor and Pain Research, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - Toni-Lee Sterley
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Jaideep S. Bains
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Jo Anne Stratton
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - John R. Matyas
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Jeff Biernaskie
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - David Dubins
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
| | | | | | | | - Loren J. Martin
- Department of Psychology, University of Toronto at Mississauga, Mississauga, ON, Canada
- Cell and Systems Biology, University of Toronto Toronto, ON, Canada
| | - Jeffrey S. Mogil
- Departments of Psychology and Anesthesia, McGill University, Montreal, QC, Canada
| | - Robert P. Bonin
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
- Cell and Systems Biology, University of Toronto Toronto, ON, Canada
- Centre for the Study of Pain, University of Toronto, Toronto, ON, Canada
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29
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Cho C, Deol HK, Martin LJ. Bridging the Translational Divide in Pain Research: Biological, Psychological and Social Considerations. Front Pharmacol 2021; 12:603186. [PMID: 33935700 PMCID: PMC8082136 DOI: 10.3389/fphar.2021.603186] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Accepted: 02/22/2021] [Indexed: 12/29/2022] Open
Abstract
A gap exists between translating basic science research into effective pain therapies in humans. While preclinical pain research has primarily used animal models to understand biological processes, a lesser focus has been toward using animal models to fully consider other components of the pain experience, such as psychological and social influences. Herein, we provide an overview of translational studies within pain research by breaking them down into purely biological, psychological and social influences using a framework derived from the biopsychosocial model. We draw from a wide landscape of studies to illustrate that the pain experience is highly intricate, and every attempt must be made to address its multiple components and interactors to aid in fully understanding its complexity. We highlight our work where we have developed animal models to assess the cognitive and social effects on pain modulation while conducting parallel experiments in people that provide proof-of-importance for human pain modulation. In some instances, human pain research has sparked the development of novel animal models, with these animal models used to better understand the complexity of phenomena considered to be uniquely human such as placebo responses and empathy.
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Affiliation(s)
- Chulmin Cho
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Harashdeep K Deol
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Loren J Martin
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON, Canada
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30
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Pain-related behaviors and abnormal cutaneous innervation in a murine model of classical Ehlers-Danlos syndrome. Pain 2021; 161:2274-2283. [PMID: 32483055 DOI: 10.1097/j.pain.0000000000001935] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Classical Ehlers-Danlos syndrome (cEDS) is a connective tissue disorder caused by heterozygous mutations in one of the type V collagen-encoding genes, COL5A1 or COL5A2. cEDS is characterized by generalized joint hypermobility and instability, hyperextensible, fragile skin, and delayed wound healing. Chronic pain is a major problem in cEDS patients, but the underlying mechanisms are largely unknown, and studies in animal models are lacking. Therefore, we assessed pain-related behaviors in haploinsufficient Col5a1 mice, which clinically mimic human cEDS. Compared to wild-type (WT) littermates, 15 to 20-week-old Col5a1 mice of both sexes showed significant hypersensitivity to mechanical stimuli in the hind paws and the abdominal area, but responses to thermal stimuli were unaltered. Spontaneous behaviors, including distance travelled and rearing, were grossly normal in male Col5a1 mice, whereas female Col5a1 mice showed altered climbing behavior. Finally, male and female Col5a1 mice vocalized more than WT littermates when scruffed. Decreased grip strength was also noted. In view of the observed pain phenotype, Col5a1 mice were crossed with NaV1.8-tdTomato reporter mice, enabling visualization of nociceptors in the glabrous skin of the footpad. We observed a significant decrease in intraepidermal nerve fiber density, with fewer nerves crossing the epidermis, and a decreased total nerve length of Col5a1 mice compared to WT. In summary, male and female Col5a1 mice show hypersensitivity to mechanical stimuli, indicative of generalized sensitization of the nervous system, in conjunction with an aberrant organization of cutaneous nociceptors. Therefore, Col5a1 mice will provide a useful tool to study mechanisms of pain associated with cEDS.
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31
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Costa FV, Rosa LV, Quadros VA, de Abreu MS, Santos ARS, Sneddon LU, Kalueff AV, Rosemberg DB. The use of zebrafish as a non-traditional model organism in translational pain research: the knowns and the unknowns. Curr Neuropharmacol 2021; 20:476-493. [PMID: 33719974 DOI: 10.2174/1570159x19666210311104408] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 02/24/2021] [Accepted: 02/28/2021] [Indexed: 11/22/2022] Open
Abstract
The ability of the nervous system to detect a wide range of noxious stimuli is crucial to avoid life-threatening injury and to trigger protective behavioral and physiological responses. Pain represents a complex phenomenon, including nociception associated with cognitive and emotional processing. Animal experimental models have been developed to understand the mechanisms involved in pain response, as well as to discover novel pharmacological and non-pharmacological anti-pain therapies. Due to the genetic tractability, similar physiology, low cost, and rich behavioral repertoire, the zebrafish (Danio rerio) has been considered a powerful aquatic model for modeling pain responses. Here, we summarize the molecular machinery of zebrafish to recognize painful stimuli, as well as emphasize how zebrafish-based pain models have been successfully used to understand specific molecular, physiological, and behavioral changes following different algogens and/or noxious stimuli (e.g., acetic acid, formalin, histamine, Complete Freund's Adjuvant, cinnamaldehyde, allyl isothiocyanate, and fin clipping). We also discuss recent advances in zebrafish-based studies and outline the potential advantages and limitations of the existing models to examine the mechanisms underlying pain responses from an evolutionary and translational perspective. Finally, we outline how zebrafish models can represent emergent tools to explore pain behaviors and pain-related mood disorders, as well as to facilitate analgesic therapy screening in translational pain research.
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Affiliation(s)
- Fabiano V Costa
- Laboratory of Experimental Neuropsychobiology, Department of Biochemistry and Molecular Biology, Natural and Exact Sciences Center, Federal University of Santa Maria RS. Brazil
| | - Luiz V Rosa
- Laboratory of Experimental Neuropsychobiology, Department of Biochemistry and Molecular Biology, Natural and Exact Sciences Center, Federal University of Santa Maria RS. Brazil
| | - Vanessa A Quadros
- Laboratory of Experimental Neuropsychobiology, Department of Biochemistry and Molecular Biology, Natural and Exact Sciences Center, Federal University of Santa Maria RS. Brazil
| | - Murilo S de Abreu
- Bioscience Institute, University of Passo Fundo (UPF), Passo Fundo, RS. Brazil
| | - Adair R S Santos
- Laboratory of Neurobiology of Pain and Inflammation, Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina, Trindade, Florianópolis, SC. Brazil
| | - Lynne U Sneddon
- University of Gothenburg, Department of Biological & Environmental Sciences, Box 461, SE-405 30 Gothenburg. Sweden
| | - Allan V Kalueff
- School of Pharmacy, Southwest University, Chongqing, China; Ural Federal University, Ekaterinburg. Russian Federation
| | - Denis B Rosemberg
- Laboratory of Experimental Neuropsychobiology, Department of Biochemistry and Molecular Biology, Natural and Exact Sciences Center, Federal University of Santa Maria RS. Brazil
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A new hypertonic saline assay for analgesic screening in mice: effects of animal strain, sex, and diurnal phase. Can J Anaesth 2021; 68:672-682. [PMID: 33598887 DOI: 10.1007/s12630-021-01923-5] [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: 08/11/2020] [Revised: 10/27/2020] [Accepted: 10/29/2020] [Indexed: 10/22/2022] Open
Abstract
PURPOSE There exists a pressing need for the identification of novel analgesics. We recently reported on a new preclinical assay for rapid analgesic screening based on intraplantar (i.pl.) injection of 10% hypertonic saline (HS) in female outbred (CD-1) mice. Herein, we characterized the HS assay's performance in inbred (C57BL/6) mice, sensitivity to sex differences, and effects of diurnal rhythm phase. METHODS In randomized, controlled, blinded in vivo animal experiments, we studied nociceptive responses induced by i.pl. HS in C57BL/6 (vs CD-1) mice of both sexes (n = 240) and determined diurnal rhythm phase effects in female animals. We established the HS assay's sensitivity to morphine by constructing dose-response curves and calculating half-maximal inhibitory doses (ID50s). RESULTS The injection of i.pl. HS produced nociceptive (licking and biting) responses in all C57BL/6 mice tested. In both C57BL/6 and CD-1 mice, the mean (95% confidence interval [CI]) response magnitudes were greater in females vs males (C57BL/6: 87 sec [64 to 110] vs 45 sec [29 to 61]; difference in means, 42 sec; 95% CI, 17 to 68; P < 0.001; n = 10/group; CD-1: 110 sec [95 to 126] vs 53 sec [32 to 74]; difference in means, 57 sec; 95% CI, 34 to 79; P < 0.001; n = 10/group). The mean (95% CI) nociceptive responses were greater at 24:00 hr than at 12:00 hr in C57BL/6 mice (64 sec [40 to 88] vs 37 sec [24 to 51]; difference in means, 27 sec; 95% CI, 7 to 47; P = 0.007; n = 10/group), but not in CD-1 mice (P = 0.97). Intravenous morphine dose-dependently attenuated nociceptive responses of both C57BL/6 and CD-1 mice (ID50, 0.6 and 2.5 mg·kg-1, respectively; P = 0.41). CONCLUSION These findings in inbred and outbred mice solidify the utility of the HS assay as an effective, rapid, robust, and versatile preclinical tool for analgesic screening.
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Liu X, Zhang JT, Hu Y, Shan WQ, Wang ZH, Fu QY, Fu DN, Ji J, Liu T. Formalin Itch Test: Low-Dose Formalin Induces Histamine-Independent, TRPA1-Mediated Itch in Mice. Front Med (Lausanne) 2021; 8:627725. [PMID: 33681255 PMCID: PMC7928323 DOI: 10.3389/fmed.2021.627725] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 01/14/2021] [Indexed: 12/13/2022] Open
Abstract
Chronic itch is a common distressing symptom of many diseases, which reduced patient's quality of life. The mechanistic study on itch and screening for new anti-itch drugs require the development of new pre-clinical itch animal models. Herein, we established an acute itch model by intradermal (i.d.) injection of low-dose formalin into the neck or cheek in mice. In mice, i.d. injection of formalin (0.1–5%) in the nape of the neck evoked robust scratching behavior in a dose-dependent manner and the dose–response curves showed an inverted “U” shape. I.d. injection of formalin (0.3–0.6%) into the cheek evoked scratching in mice but wiping in rats, while formalin (1.25–5%) induced mixed wiping and scratching behavior in both mice and rats. Further, we found that 0.3% formalin-induced scratching was histamine-independent and significantly attenuated by transient receptor potential ion channel A1 (TRPA1) inhibitor (HC030031) or in TRPA1 knockout (KO) mice, but not affected by transient receptor potential ion channel V1 (TRPV1) inhibitor (capsazepine) or in TRPV1 KO mice. Additionally, 0.3% formalin-induced up-regulation of phosphorylation of extracellular regulated protein kinases (p-ERK) in the dorsal root ganglion (DRG) and scratching were suppressed by intrathecal injection of MEK inhibitor U0126 in mice. Incubation of 0.03% formalin induced the accumulation of intracellular reactive oxygen species (ROS) in the cultured DRG-derived cell line ND7-23, and formalin-induced itch was suppressed by antioxidants in mice. Finally, perfusion of 0.03% formalin induced elevation of intracellular calcium in a subset of primary cultured DRG neurons of mice. Thus, these results indicate that low-dose formalin induced non-histaminergic itch by activation of TRPA1 in mice, which may be employed as a useful acute itch model for screening potential anti-itch drugs.
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Affiliation(s)
- Xu Liu
- Department of Dermatology, The Second Affiliated Hospital of Soochow University, Suzhou, China.,Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Jiang-Tao Zhang
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Yue Hu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Wen-Qi Shan
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Zhi-Hong Wang
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Qing-Yue Fu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Dan-Ni Fu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Jiang Ji
- Department of Dermatology, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Tong Liu
- Institute of Pain Medicine and Special Environmental Medicine, Nantong University, Nantong, China.,College of Life Sciences, Yanan University, Yanan, China
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Midavaine É, Côté J, Marchand S, Sarret P. Glial and neuroimmune cell choreography in sexually dimorphic pain signaling. Neurosci Biobehav Rev 2021; 125:168-192. [PMID: 33582232 DOI: 10.1016/j.neubiorev.2021.01.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 11/03/2020] [Accepted: 01/25/2021] [Indexed: 12/17/2022]
Abstract
Chronic pain is a major global health issue that affects all populations regardless of sex, age, ethnicity/race, or country of origin, leading to persistent physical and emotional distress and to the loss of patients' autonomy and quality of life. Despite tremendous efforts in the elucidation of the mechanisms contributing to the pathogenesis of chronic pain, the identification of new potential pain targets, and the development of novel analgesics, the pharmacological treatment options available for pain management remain limited, and most novel pain medications have failed to achieve advanced clinical development, leaving many patients with unbearable and undermanaged pain. Sex-specific susceptibility to chronic pain conditions as well as sex differences in pain sensitivity, pain tolerance and analgesic efficacy are increasingly recognized in the literature and have thus prompted scientists to seek mechanistic explanations. Hence, recent findings have highlighted that the signaling mechanisms underlying pain hypersensitivity are sexually dimorphic, which sheds light on the importance of conducting preclinical and clinical pain research on both sexes and of developing sex-specific pain medications. This review thus focuses on the clinical and preclinical evidence supporting the existence of sex differences in pain neurobiology. Attention is drawn to the sexually dimorphic role of glial and immune cells, which are both recognized as key players in neuroglial maladaptive plasticity at the origin of the transition from acute pain to chronic pathological pain. Growing evidence notably attributes to microglial cells a pivotal role in the sexually dimorphic pain phenotype and in the sexually dimorphic analgesic efficacy of opioids. This review also summarizes the recent advances in understanding the pathobiology underpinning the development of pain hypersensitivity in both males and females in different types of pain conditions, with particular emphasis on the mechanistic signaling pathways driving sexually dimorphic pain responses.
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Affiliation(s)
- Élora Midavaine
- Department of Pharmacology-Physiology, Institut de pharmacologie de Sherbrooke, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du Centre hospitalier universitaire de Sherbrooke, CIUSSS de l'Estrie - CHUS, Sherbrooke, Québec, Canada.
| | - Jérôme Côté
- Department of Pharmacology-Physiology, Institut de pharmacologie de Sherbrooke, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du Centre hospitalier universitaire de Sherbrooke, CIUSSS de l'Estrie - CHUS, Sherbrooke, Québec, Canada
| | - Serge Marchand
- Department of Pharmacology-Physiology, Institut de pharmacologie de Sherbrooke, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du Centre hospitalier universitaire de Sherbrooke, CIUSSS de l'Estrie - CHUS, Sherbrooke, Québec, Canada
| | - Philippe Sarret
- Department of Pharmacology-Physiology, Institut de pharmacologie de Sherbrooke, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du Centre hospitalier universitaire de Sherbrooke, CIUSSS de l'Estrie - CHUS, Sherbrooke, Québec, Canada.
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35
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Locke S, Yousefpour N, Ribeiro-da-Silva A. Dorsal horn disinhibition and movement-induced behaviour in a rat model of inflammatory arthritis. Rheumatology (Oxford) 2021; 60:918-928. [PMID: 32910183 DOI: 10.1093/rheumatology/keaa396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 06/08/2020] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVES Alterations beyond joint inflammation such as changes in dorsal horn (DH) excitability contribute to pain in inflammatory arthritis (IA). More complete understanding of specific underlying mechanisms will be important to define novel targets for the treatment of IA pain. Pre-clinical models are useful, but relevant pain assays are vital for successful clinical translation. For this purpose, a method is presented to assess movement-induced pain-related behaviour changes that was subsequently used to investigate DH disinhibition in IA. METHODS IA was induced by intra-articular injection of complete Freund's adjuvant (CFA) in male rats, and weight distribution was assessed before and after walking on a treadmill. To confirm increased activity in nociception-related pathways, fos expression was assessed in the superficial DH, including in nociceptive neurons, identified by neurokinin 1 (NK1) immunoreactivity, and interneurons. Inhibitory terminal density onto NK1+ neurons was assessed and lastly, a cohort of animals was treated for 3 days with gabapentin. RESULTS At 4 weeks post-CFA, walking reduced weight distribution to the affected joint and increased DH fos expression, including in NK1+ neurons. Neuronal activity in inhibitory cells and inhibitory terminal density on NK1+ neurons were decreased in CFA-treated animals compared with controls. Treatment with gabapentin led to recovered behaviour and DH neuronal activity pattern in CFA-treated animals. CONCLUSION We describe an assay to assess movement-induced pain-related behaviour changes in a rodent IA model. Furthermore, our results suggest that disinhibition may contribute to pain related to movement in IA.
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Affiliation(s)
- Samantha Locke
- Department of Pharmacology and Therapeutics, Montreal, Quebec, Canada.,Alan Edwards Centre for Research on Pain, Montreal, Quebec, Canada
| | - Noosha Yousefpour
- Department of Pharmacology and Therapeutics, Montreal, Quebec, Canada.,Alan Edwards Centre for Research on Pain, Montreal, Quebec, Canada
| | - Alfredo Ribeiro-da-Silva
- Department of Pharmacology and Therapeutics, Montreal, Quebec, Canada.,Alan Edwards Centre for Research on Pain, Montreal, Quebec, Canada.,Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
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36
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Fullerton EF, Rubaharan M, Karom MC, Hanberry RI, Murphy AZ. Advanced age attenuates the antihyperalgesic effect of morphine and decreases μ-opioid receptor expression and binding in the rat midbrain periaqueductal gray in male and female rats. Neurobiol Aging 2021; 98:78-87. [PMID: 33249376 PMCID: PMC8673746 DOI: 10.1016/j.neurobiolaging.2020.10.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 09/23/2020] [Accepted: 10/22/2020] [Indexed: 02/08/2023]
Abstract
The present study investigated the impact of advanced age on morphine modulation of persistent inflammatory pain in male and female rats. The impact of age, sex, and pain on μ-opioid receptor (MOR) expression and binding in the ventrolateral periaqueductal gray (vlPAG) was also examined using immunohistochemistry and receptor autoradiography. Intraplantar administration of complete Freund's adjuvant induced comparable levels of edema and hyperalgesia in adult (2-3 mos) and aged (16-18 mos) male and female rats. Morphine potency was highest in adult males, with a greater than two-fold increase in morphine EC50 observed in adult versus aged males (3.83 mg/kg vs. 10.16 mg/kg). Adult and aged female rats also exhibited significantly higher EC50 values (7.76 mg/kg and 8.74 mg/kg, respectively) than adult males. The upward shift in EC50 from adult to aged males was paralleled by a reduction in vlPAG MOR expression and binding. The observed age-related reductions in morphine potency and vlPAG MOR expression and binding have significant implications in pain management in the aged population.
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Affiliation(s)
- Evan F Fullerton
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA
| | | | - Mary C Karom
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA
| | | | - Anne Z Murphy
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA.
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37
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Li J, Zain M, Bonin RP. Differential modulation of thermal preference after sensitization by optogenetic or pharmacological activation of heat-sensitive nociceptors. Mol Pain 2021; 17:17448069211000910. [PMID: 33719729 PMCID: PMC7960897 DOI: 10.1177/17448069211000910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 01/24/2021] [Accepted: 02/10/2021] [Indexed: 11/22/2022] Open
Abstract
Common approaches to studying mechanisms of chronic pain and sensory changes in pre-clinical animal models involve measurement of acute, reflexive withdrawal responses evoked by noxious stimuli. These methods typically do not capture more subtle changes in sensory processing nor report on the consequent behavioral changes. In addition, data collection and analysis protocols are often labour-intensive and require direct investigator interactions, potentially introducing bias. In this study, we develop and characterize a low-cost, easily assembled behavioral assay that yields self-reported temperature preference from mice that is responsive to peripheral sensitization. This system uses a partially automated and freely available analysis pipeline to streamline the data collection process and enable objective analysis. We found that after intraplantar administration of the TrpV1 agonist, capsaicin, mice preferred to stay in cooler temperatures than saline injected mice. We further observed that gabapentin, a non-opioid analgesic commonly prescribed to treat chronic pain, reversed this aversion to higher temperatures. In contrast, optogenetic activation of the central terminals of TrpV1+ primary afferents via in vivo spinal light delivery did not induce a similar change in thermal preference, indicating a possible role for peripheral nociceptor activity in the modulation of temperature preference. We conclude that this easily produced and robust sensory assay provides an alternative approach to investigate the contribution of central and peripheral mechanisms of sensory processing that does not rely on reflexive responses evoked by noxious stimuli.
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Affiliation(s)
- Jerry Li
- Department of Human Biology: Neuroscience and Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Maham Zain
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Robert P Bonin
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
- University of Toronto Centre for the Study of Pain, University of Toronto, Toronto, Ontario, Canada
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38
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Novel 1,3,4-Oxadiazole Derivatives of Pyrrolo[3,4- d]pyridazinone Exert Antinociceptive Activity in the Tail-Flick and Formalin Test in Rodents and Reveal Reduced Gastrotoxicity. Int J Mol Sci 2020; 21:ijms21249685. [PMID: 33353118 PMCID: PMC7766312 DOI: 10.3390/ijms21249685] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 12/13/2020] [Accepted: 12/16/2020] [Indexed: 12/12/2022] Open
Abstract
Despite the availability of the current drug arsenal for pain management, there is still a clinical need to identify new, more effective, and safer analgesics. Based on our earlier study, newly synthesized 1,3,4-oxadiazole derivatives of pyrrolo[3,4-d]pyridazinone, especially 10b and 13b, seem to be promising as potential analgesics. The current study was designed to investigate whether novel derivatives attenuate nociceptive response in animals subjected to thermal or chemical noxious stimulus, and to compare this effect to reference drugs. The antinociceptive effect of novel compounds was studied using the tail-flick and formalin test. Pretreatment with novel compounds at all studied doses increased the latency time in the tail-flick test and decreased the licking time during the early phase of the formalin test. New derivatives given at the medium and high doses also reduced the late phase of the formalin test. The achieved results indicate that new derivatives dose-dependently attenuate nociceptive response in both models of pain and exert a lack of gastrotoxicity. Both studied compounds act more efficiently than indomethacin, but not morphine. Compound 13b at the high dose exerts the greatest antinociceptive effect. It may be due to the reduction of nociceptor sensitization via prostaglandin E2 and myeloperoxidase levels decrease.
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39
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Chronic pain impact on rodents’ behavioral repertoire. Neurosci Biobehav Rev 2020; 119:101-127. [DOI: 10.1016/j.neubiorev.2020.09.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 07/14/2020] [Accepted: 09/21/2020] [Indexed: 12/20/2022]
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40
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Abboud C, Duveau A, Bouali-Benazzouz R, Massé K, Mattar J, Brochoire L, Fossat P, Boué-Grabot E, Hleihel W, Landry M. Animal models of pain: Diversity and benefits. J Neurosci Methods 2020; 348:108997. [PMID: 33188801 DOI: 10.1016/j.jneumeth.2020.108997] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 11/03/2020] [Accepted: 11/08/2020] [Indexed: 12/15/2022]
Abstract
Chronic pain is a maladaptive neurological disease that remains a major health problem. A deepening of our knowledge on mechanisms that cause pain is a prerequisite to developing novel treatments. A large variety of animal models of pain has been developed that recapitulate the diverse symptoms of different pain pathologies. These models reproduce different pain phenotypes and remain necessary to examine the multidimensional aspects of pain and understand the cellular and molecular basis underlying pain conditions. In this review, we propose an overview of animal models, from simple organisms to rodents and non-human primates and the specific traits of pain pathologies they model. We present the main behavioral tests for assessing pain and investing the underpinning mechanisms of chronic pathological pain. The validity of animal models is analysed based on their ability to mimic human clinical diseases and to predict treatment outcomes. Refine characterization of pathological phenotypes also requires to consider pain globally using specific procedures dedicated to study emotional comorbidities of pain. We discuss the limitations of pain models when research findings fail to be translated from animal models to human clinics. But we also point to some recent successes in analgesic drug development that highlight strategies for improving the predictive validity of animal models of pain. Finally, we emphasize the importance of using assortments of preclinical pain models to identify pain subtype mechanisms, and to foster the development of better analgesics.
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Affiliation(s)
- Cynthia Abboud
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000 Bordeaux, France; Univ. Bordeaux, CNRS, Institute for Neurodegenerative Diseases, IMN, UMR 5293, F-33000 Bordeaux, France; Faculty of Arts and Sciences, Holy Spirit University of Kaslik (USEK), Lebanon
| | - Alexia Duveau
- Univ. Bordeaux, CNRS, Institute for Neurodegenerative Diseases, IMN, UMR 5293, F-33000 Bordeaux, France
| | - Rabia Bouali-Benazzouz
- Univ. Bordeaux, CNRS, Institute for Neurodegenerative Diseases, IMN, UMR 5293, F-33000 Bordeaux, France
| | - Karine Massé
- Univ. Bordeaux, CNRS, Institute for Neurodegenerative Diseases, IMN, UMR 5293, F-33000 Bordeaux, France
| | - Joseph Mattar
- School of Medicine and Medical Sciences, Holy Spirit University of Kaslik (USEK), Lebanon
| | - Louison Brochoire
- Univ. Bordeaux, CNRS, Institute for Neurodegenerative Diseases, IMN, UMR 5293, F-33000 Bordeaux, France
| | - Pascal Fossat
- Univ. Bordeaux, CNRS, Institute for Neurodegenerative Diseases, IMN, UMR 5293, F-33000 Bordeaux, France
| | - Eric Boué-Grabot
- Univ. Bordeaux, CNRS, Institute for Neurodegenerative Diseases, IMN, UMR 5293, F-33000 Bordeaux, France
| | - Walid Hleihel
- School of Medicine and Medical Sciences, Holy Spirit University of Kaslik (USEK), Lebanon; Faculty of Arts and Sciences, Holy Spirit University of Kaslik (USEK), Lebanon
| | - Marc Landry
- Univ. Bordeaux, CNRS, Institute for Neurodegenerative Diseases, IMN, UMR 5293, F-33000 Bordeaux, France.
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41
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Cabañero D, Ramírez-López A, Drews E, Schmöle A, Otte DM, Wawrzczak-Bargiela A, Huerga Encabo H, Kummer S, Ferrer-Montiel A, Przewlocki R, Zimmer A, Maldonado R. Protective role of neuronal and lymphoid cannabinoid CB 2 receptors in neuropathic pain. eLife 2020; 9:55582. [PMID: 32687056 PMCID: PMC7384863 DOI: 10.7554/elife.55582] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 07/19/2020] [Indexed: 12/14/2022] Open
Abstract
Cannabinoid CB2 receptor (CB2) agonists are potential analgesics void of psychotropic effects. Peripheral immune cells, neurons and glia express CB2; however, the involvement of CB2 from these cells in neuropathic pain remains unresolved. We explored spontaneous neuropathic pain through on-demand self-administration of the selective CB2 agonist JWH133 in wild-type and knockout mice lacking CB2 in neurons, monocytes or constitutively. Operant self-administration reflected drug-taking to alleviate spontaneous pain, nociceptive and affective manifestations. While constitutive deletion of CB2 disrupted JWH133-taking behavior, this behavior was not modified in monocyte-specific CB2 knockouts and was increased in mice defective in neuronal CB2 knockouts suggestive of increased spontaneous pain. Interestingly, CB2-positive lymphocytes infiltrated the injured nerve and possible CB2transfer from immune cells to neurons was found. Lymphocyte CB2depletion also exacerbated JWH133 self-administration and inhibited antinociception. This work identifies a simultaneous activity of neuronal and lymphoid CB2that protects against spontaneous and evoked neuropathic pain.
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Affiliation(s)
- David Cabañero
- Laboratory of Neuropharmacology, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain.,Institute of Research, Development and Innovation in Healthcare Biotechnology of Elche (IDiBE), Universidad Miguel Hernández de Elche, Alicante, Spain
| | - Angela Ramírez-López
- Laboratory of Neuropharmacology, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Eva Drews
- Institute of Molecular Psychiatry, University of Bonn, Bonn, Germany
| | - Anne Schmöle
- Institute of Molecular Psychiatry, University of Bonn, Bonn, Germany
| | - David M Otte
- Institute of Molecular Psychiatry, University of Bonn, Bonn, Germany
| | - Agnieszka Wawrzczak-Bargiela
- Department of Pharmacology, Laboratory of Pharmacology and Brain Biostructure, Maj Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Hector Huerga Encabo
- Immunology Unit, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain.,Haematopoietic Stem Cell Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Sami Kummer
- Laboratory of Neuropharmacology, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Antonio Ferrer-Montiel
- Institute of Research, Development and Innovation in Healthcare Biotechnology of Elche (IDiBE), Universidad Miguel Hernández de Elche, Alicante, Spain
| | - Ryszard Przewlocki
- Department of Molecular Neuropharmacology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Andreas Zimmer
- Institute of Molecular Psychiatry, University of Bonn, Bonn, Germany
| | - Rafael Maldonado
- Laboratory of Neuropharmacology, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain.,IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain
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42
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Cata JP, Gorur A, Yuan X, Berg NK, Sood AK, Eltzschig HK. Role of Micro-RNA for Pain After Surgery. Anesth Analg 2020; 130:1638-1652. [DOI: 10.1213/ane.0000000000004767] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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43
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Just N, Segelcke D, Sandbrink M, Pogatzki-Zahn E, Faber C. Development of a Stimulator for the Characterization of Mechanical-Evoked Pain-Related Supra-Spinal Processing Using BOLD-fMRI in Rodents. IEEE Trans Biomed Eng 2020; 67:1349-1356. [DOI: 10.1109/tbme.2019.2936571] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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44
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Reker AN, Chen S, Etter K, Burger T, Caudill M, Davidson S. The Operant Plantar Thermal Assay: A Novel Device for Assessing Thermal Pain Tolerance in Mice. eNeuro 2020; 7:ENEURO.0210-19.2020. [PMID: 32071073 PMCID: PMC7078811 DOI: 10.1523/eneuro.0210-19.2020] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 01/27/2020] [Accepted: 01/31/2020] [Indexed: 02/07/2023] Open
Abstract
Pain is a multidimensional experience of sensory-discriminative, cognitive, and affective processes; however, current basic research methods rely heavily on response to threshold stimuli, bypassing the supraspinal processing that ultimately gives rise to the pain experience. We developed the operant plantar thermal assay (OPTA), which utilizes a novel, conflict-based operant task requiring evaluation and active decision-making to obtain reward under thermally aversive conditions to quantify thermal pain tolerance. In baseline measures, male and female mice exhibited similar temperature preferences, however in the OPTA, female mice exhibited greater temperature-dependent tolerance, as defined by choice time spent in an adverse thermal condition to obtain reward. Increasing reward salience (4% vs 10% sucrose solution) led to increased thermal tolerance for males but not females. To determine whether neuropathic and inflammatory pain models alter thermal tolerance, animals with chronic constriction injury (CCI) or complete Freund's adjuvant (CFA), respectively, were tested in the OPTA. Surprisingly, neuropathic animals exhibited increased thermal tolerance, as shown by greater time spent in the reward zone in an adverse thermal condition, compared with sham animals. There was no effect of inflammation on thermal tolerance. Administration of clonidine in the CCI model led to increased thermal tolerance in both injured and sham animals. In contrast, the non-steroidal anti-inflammatory meloxicam was anti-hyperalgesic in the CFA model, but reduced thermal pain tolerance. These data support the feasibility of using the OPTA to assess thermal pain tolerance to gain new insights into complex pain behaviors and to investigate novel aspects of analgesic efficacy.
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Affiliation(s)
- Ashlie N Reker
- Department of Anesthesiology and Pain Research Center, University of Cincinnati, College of Medicine, Cincinnati, OH 45267
| | - Sisi Chen
- Department of Anesthesiology and Pain Research Center, University of Cincinnati, College of Medicine, Cincinnati, OH 45267
| | - Katherine Etter
- Department of Anesthesiology and Pain Research Center, University of Cincinnati, College of Medicine, Cincinnati, OH 45267
| | - Taylor Burger
- Department of Anesthesiology and Pain Research Center, University of Cincinnati, College of Medicine, Cincinnati, OH 45267
| | - Makayla Caudill
- Department of Anesthesiology and Pain Research Center, University of Cincinnati, College of Medicine, Cincinnati, OH 45267
| | - Steve Davidson
- Department of Anesthesiology and Pain Research Center, University of Cincinnati, College of Medicine, Cincinnati, OH 45267
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45
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Ozbakir HF, Anderson NT, Fan KC, Mukherjee A. Beyond the Green Fluorescent Protein: Biomolecular Reporters for Anaerobic and Deep-Tissue Imaging. Bioconjug Chem 2020; 31:293-302. [PMID: 31794658 PMCID: PMC7033020 DOI: 10.1021/acs.bioconjchem.9b00688] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Fluorescence imaging represents cornerstone technology for studying biological function at the cellular and molecular levels. The technology's centerpiece is a prolific collection of genetic reporters based on the green fluorescent protein (GFP) and related analogs. More than two decades of protein engineering have endowed the GFP repertoire with an incredible assortment of fluorescent proteins, allowing scientists immense latitude in choosing reporters tailored to various cellular and environmental contexts. Nevertheless, GFP and derivative reporters have specific limitations that hinder their unrestricted use for molecular imaging. These challenges have inspired the development of new reporter proteins and imaging mechanisms. Here, we review how these developments are expanding the frontiers of reporter gene techniques to enable nondestructive studies of cell function in anaerobic environments and deep inside intact animals-two important biological contexts that are fundamentally incompatible with the use of GFP-based reporters.
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Affiliation(s)
- Harun F. Ozbakir
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Nolan T. Anderson
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Kang-Ching Fan
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Arnab Mukherjee
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
- Department of Chemistry, University of California, Santa Barbara, California 93106, United States
- Neuroscience Research Institute, University of California, Santa Barbara, California 93106, United States
- Center for Bioengineering, University of California, Santa Barbara, California 93106, United States
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46
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Edwards S, Vendruscolo LF, Gilpin NW, Wojnar M, Witkiewitz K. Alcohol and Pain: A Translational Review of Preclinical and Clinical Findings to Inform Future Treatment Strategies. Alcohol Clin Exp Res 2020; 44:368-383. [PMID: 31840821 PMCID: PMC11004915 DOI: 10.1111/acer.14260] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 11/28/2019] [Indexed: 12/13/2022]
Abstract
Alcohol use disorder (AUD) and chronic pain are enduring and devastating conditions that share an intersecting epidemiology and neurobiology. Chronic alcohol use itself can produce a characteristic painful neuropathy, while the regular analgesic use of alcohol in the context of nociceptive sensitization and heightened affective pain sensitivity may promote negative reinforcement mechanisms that underlie AUD maintenance and progression. The goal of this review was to provide a broad translational framework that communicates research findings spanning preclinical and clinical studies, including a review of genetic, molecular, behavioral, and social mechanisms that facilitate interactions between persistent pain and alcohol use. We also consider recent evidence that will shape future investigations into novel treatment mechanisms for pain in individuals suffering from AUD.
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Affiliation(s)
- Scott Edwards
- Department of Physiology and Comprehensive Alcohol-HIV/AIDS Research Center, LSU Health Sciences Center, New Orleans, LA 70112
| | - Leandro F. Vendruscolo
- National Institute on Drug Abuse (NIDA), Intramural Research Program (IRP), Baltimore, MD 21224
| | - Nicholas W. Gilpin
- Department of Physiology and Comprehensive Alcohol-HIV/AIDS Research Center, LSU Health Sciences Center, New Orleans, LA 70112
| | - Marcin Wojnar
- Department of Psychiatry, Medical University of Warsaw, Warsaw, Poland
- Department of Psychiatry, University of Michigan, Ann Arbor, MI 48109
| | - Katie Witkiewitz
- Department of Psychology, University of New Mexico, Albuquerque NM 87131
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47
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Herzberg D, Strobel P, Müller H, Meneses C, Werner M, Bustamante H. Proteomic profiling of proteins in the dorsal horn of the spinal cord in dairy cows with chronic lameness. PLoS One 2020; 15:e0228134. [PMID: 31990932 PMCID: PMC6986711 DOI: 10.1371/journal.pone.0228134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 01/08/2020] [Indexed: 01/03/2023] Open
Abstract
Chronic lameness affects bovine welfare and has a negative economic impact in dairy industry. Moreover, due to the translational gap between traditional pain models and new drugs development for treating chronic pain states, naturally occurring painful diseases could be a potential translational tool for chronic pain research. We therefore employed liquid chromatography tandem mass spectrometry (LC-MS/MS) to stablish the proteomic profile of the spinal cord samples from lumbar segments (L2-L4) of chronic lame dairy cows. Data were validated and quantified through software tool (Scaffold® v 4.0) using output data from two search engines (SEQUEST® and X-Tandem®). Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) analysis was performed to detect proteins interactions. LC-MS/MS identified a total amount of 177 proteins; of which 129 proteins were able to be quantified. Lame cows showed a strong upregulation of interacting proteins with chaperone and stress functions such as Hsp70 (p < 0.006), Hsc70 (p < 0.0079), Hsp90 (p < 0.015), STIP (p > 0.0018) and Grp78 (p <0.0068), and interacting proteins associated to glycolytic pathway such as; γ-enolase (p < 0.0095), α-enolase (p < 0.013) and hexokinase-1 (p < 0.028). It was not possible to establish a clear network of interaction in several upregulated proteins in lame cows. Non-interacting proteins were mainly associated to redox process and cytoskeletal organization. The most relevant down regulated protein in lame cows was myelin basic protein (MBP) (p < 0.02). Chronic inflammatory lameness in cows is associated to increased expression of stress proteins with chaperone, metabolism, redox and structural functions. A state of endoplasmic reticulum stress and unfolded protein response (UPR) might explain the changes in protein expression in lame cows; however, further studies need to be performed in order to confirm these findings.
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Affiliation(s)
- Daniel Herzberg
- Veterinary Clinical Sciences Department, Faculty of Veterinary Science, Universidad Austral de Chile, Valdivia, Chile
- * E-mail: (HB); (DH)
| | - Pablo Strobel
- Animal Science Department, Faculty of Veterinary Science, Universidad Austral de Chile, Valdivia, Chile
| | - Heine Müller
- Veterinary Clinical Sciences Department, Faculty of Veterinary Science, Universidad Austral de Chile, Valdivia, Chile
| | - Constanza Meneses
- Comparative Biomedical Science Graduate Program, College of Veterinary Medicine, North Caroline State University, Raleigh, North Carolina, United States of America
| | - Marianne Werner
- Animal Science Department, Faculty of Veterinary Science, Universidad Austral de Chile, Valdivia, Chile
| | - Hedie Bustamante
- Veterinary Clinical Sciences Department, Faculty of Veterinary Science, Universidad Austral de Chile, Valdivia, Chile
- * E-mail: (HB); (DH)
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48
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Smith JC. A Review of Strain and Sex Differences in Response to Pain and Analgesia in Mice. Comp Med 2019; 69:490-500. [PMID: 31822324 DOI: 10.30802/aalas-cm-19-000066] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Pain and its alleviation are currently a highly studied issue in human health. Research on pain and response to analgesia has evolved to include the effects of genetics, heritability, and sex as important components in both humans and animals. The laboratory mouse is the major animal studied in the field of pain and analgesia. Studying the inbred mouse to understand how genetic heritable traits and/or sex influence pain and analgesia has added valuable information to the complex nature of pain as a human disease. In the context of biomedical research, identifying pain and ensuring its control through analgesia in research animals remains one of the hallmark responsibilities of the research community. Advancements in both human and mouse genomic research shed light not only on the need to understand how both strain and sex affect the mouse pain response but also on how these research achievements can be used to improve the humane use of all research animal species. A better understanding of how strain and sex affect the response to pain may allow researchers to improve study design and thereby the reproducibility of animal research studies. The need to use both sexes, along with an improved understanding of how genetic heritability affects nociception and analgesic sensitivity, remains a key priority for pain researchers working with mice. This review summarizes the current literature on how strain and sex alter the response to pain and analgesia in the modern research mouse, and highlights the importance of both strain and sex selection in pain research.
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Affiliation(s)
- Jennifer C Smith
- Department of Bioresources, Henry Ford Health System, Detroit, Michigan;,
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49
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The emergence of animal models of chronic pain and logistical and methodological issues concerning their use. J Neural Transm (Vienna) 2019; 127:393-406. [DOI: 10.1007/s00702-019-02103-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 11/07/2019] [Indexed: 12/12/2022]
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50
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Advances in assessment of pain behaviors and mechanisms of post-operative pain models. CURRENT OPINION IN PHYSIOLOGY 2019. [DOI: 10.1016/j.cophys.2019.07.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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