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Negus SS. Core Outcome Measures in Preclinical Assessment of Candidate Analgesics. Pharmacol Rev 2019; 71:225-266. [PMID: 30898855 PMCID: PMC6448246 DOI: 10.1124/pr.118.017210] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
All preclinical procedures for analgesic drug discovery involve two components: 1) a “pain stimulus” (the principal independent variable), which is delivered to an experimental subject with the intention of producing a pain state; and 2) a “pain behavior” (the principal dependent variable), which is measured as evidence of that pain state. Candidate analgesics are then evaluated for their effectiveness to reduce the pain behavior, and results are used to prioritize drugs for advancement to clinical testing. This review describes a taxonomy of preclinical procedures organized into an “antinociception matrix” by reference to their types of pain stimulus (noxious, inflammatory, neuropathic, disease related) and pain behavior (unconditioned, classically conditioned, operant conditioned). Particular emphasis is devoted to pain behaviors and the behavioral principals that govern their expression, pharmacological modulation, and preclinical-to-clinical translation. Strengths and weaknesses are compared and contrasted for procedures using each type of behavioral outcome measure, and the following four recommendations are offered to promote strategic use of these procedures for preclinical-to-clinical analgesic drug testing. First, attend to the degree of homology between preclinical and clinical outcome measures, and use preclinical procedures with behavioral outcome measures homologous to clinically relevant outcomes in humans. Second, use combinations of preclinical procedures with complementary strengths and weaknesses to optimize both sensitivity and selectivity of preclinical testing. Third, take advantage of failed clinical translation to identify drugs that can be back-translated preclinically as active negative controls. Finally, increase precision of procedure labels by indicating both the pain stimulus and the pain behavior in naming preclinical procedures.
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Affiliation(s)
- S Stevens Negus
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia
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52
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Evaluation of the Antinociceptive Effect of Maropitant, a Neurokinin-1 Receptor Antagonist, in Cats Undergoing Ovariohysterectomy. Vet Med Int 2019; 2019:9352528. [PMID: 31093325 PMCID: PMC6476118 DOI: 10.1155/2019/9352528] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Revised: 01/24/2019] [Accepted: 02/20/2019] [Indexed: 12/14/2022] Open
Abstract
Maropitant is a neurokinin-1 (NK1) receptor antagonist that can be used for pain management. The objective of this study was to evaluate the effect of continuous infusion of two doses of maropitant on cardiorespiratory parameters and its postoperative analgesic effect in cats undergoing ovariohysterectomy. Thirty cats were randomly assigned to one of three groups (10 cats each group): the control group (CG) received a continuous infusion of 10 ml/kg/h Ringer's lactate; GM30 and GM100 first received an intravenous (IV) bolus of 1 mg/kg maropitant; GM30 then received continuous infusion of 30 μg/kg/h maropitant; and GM100 then received continuous infusion of 100 μg/kg/h maropitant. The maropitant was diluted into Ringer's lactate and the GM30 and GM100 also received fluids intraoperatively. In all groups, premedication included intramuscular injections of morphine and acepromazine, followed by induction with propofol and maintenance with isoflurane. Temperature, heart rate (HR), Doppler blood pressure (DBP), respiratory rate, oxygen saturation, and measuring the end-tidal carbon dioxide and isoflurane were monitored. Postoperative pain was evaluated using a visual analog scale and the UNESP-Botucatu multidimensional composite pain scale in cats; morphine was used for analgesic rescue. During the surgical procedure, cats in GM100 demonstrated lower HR and DBP than those in CG. With regard to the evaluation of postoperative pain, GM100 required the least frequent morphine rescue and less rescue analgesia compared with CG. In conclusion, cats in GM100 maintained lower DBP and HR and required lower analgesic rescue during the postoperative period. The results suggested that animals receiving maropitant bolus (1 mg/kg) plus (100 μg/kg/h) experienced greater postoperative comfort, reflected by the lesser need for analgesic rescue. The use of maropitant in surgical procedures in cats contributes to postoperative comfort.
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53
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Karlsson B, Burell G, Kristiansson P, Björkegren K, Nyberg F, Svärdsudd K. Decline of substance P levels after stress management with cognitive behaviour therapy in women with the fibromyalgia syndrome. Scand J Pain 2019; 19:473-482. [DOI: 10.1515/sjpain-2018-0324] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 01/22/2019] [Indexed: 12/25/2022]
Abstract
Abstract
Background and aims
Substance P (CSF-SP) is known to be elevated in females with fibromyalgia syndrome (FMS). The aims of this study were to evaluate the effect of cognitive behaviour therapy (CBT) on plasma SP levels in women with FMS and to find possible clinical behavioural correlates to plasma SP level changes.
Methods
Forty-eight women with FMS were randomly allocated into two groups. Group 1 received the CBT treatment intervention over the course of 6 months while group 2 was waitlisted. CBT was given with a protocol developed to diminish stress and pain. After 6 months, group 2 was given the same CBT treatment as well. All were followed up 1 year after the start of CBT treatment. This approach allowed for two analytical designs – a randomised controlled trial (RCT) (n=24 vs. n=24) and a before-and-after treatment design (n=48). All women were repeatedly evaluated by the West Haven-Yale Multidimensional Pain Inventory (MPI) and three other psychometric questionnaires and plasma SP was analysed.
Results
In the RCT design, the plasma SP level was 8.79 fmol/mL in both groups at the start of the trial, after adjustment for initial differences. At the end of the RCT, the plasma SP level was 5.25 fmol/mL in the CBT intervention group compared to 8.39 fmol/mL in the control group (p=0.02). In the before-and-after design, the plasma SP was reduced by 33% (p<0.01) after CBT, but returned to the pre-treatment level at follow-up 1 year after the start of CBT treatment. Plasma SP was associated with the MPI dimensions experienced “support from spouses or significant others” and “life control”.
Conclusions
Plasma SP might be a marker of the effect of CBT in FMS associated with better coping strategies and reduced stress rather than a biochemical marker of pain.
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Affiliation(s)
- Bo Karlsson
- Department of Public Health and Caring Sciences , Uppsala University , Uppsala SE-751 22 , Sweden
| | - Gunilla Burell
- Department of Public Health and Caring Sciences , Uppsala University , Uppsala SE-751 22 , Sweden
| | - Per Kristiansson
- Department of Public Health and Caring Sciences , Uppsala University , Uppsala SE-751 22 , Sweden
| | - Karin Björkegren
- Department of Public Health and Caring Sciences , Uppsala University , Uppsala SE-751 22 , Sweden
| | - Fred Nyberg
- Department of Pharmaceutical Biosciences , Uppsala University , Uppsala SE-751 22 , Sweden
| | - Kurt Svärdsudd
- Department of Public Health and Caring Sciences , Uppsala University , Uppsala SE-751 22 , Sweden
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54
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Green DP, Limjunyawong N, Gour N, Pundir P, Dong X. A Mast-Cell-Specific Receptor Mediates Neurogenic Inflammation and Pain. Neuron 2019; 101:412-420.e3. [PMID: 30686732 DOI: 10.1016/j.neuron.2019.01.012] [Citation(s) in RCA: 221] [Impact Index Per Article: 44.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 10/29/2018] [Accepted: 12/31/2018] [Indexed: 12/12/2022]
Abstract
Mast cells can be found in close proximity to peripheral nerve endings where, upon activation, they release a broad range of pro-inflammatory cytokines and chemokines. However, the precise mechanism underlying this so-called neurogenic inflammation and associated pain has remained elusive. Here we report that the mast-cell-specific receptor Mrgprb2 mediates inflammatory mechanical and thermal hyperalgesia and is required for recruitment of innate immune cells at the injury site. We also found that the neuropeptide substance P (SP), an endogenous agonist of Mrgprb2, facilitates immune cells' migration via Mrgprb2. Furthermore, SP activation of the human mast cell led to the release of multiple pro-inflammatory cytokines and chemokines via the human homolog MRGPRX2. Surprisingly, the SP-mediated inflammatory responses were independent of its canonical receptor, neurokinin-1 receptor (NK-1R). These results identify Mrgprb2/X2 as an important neuroimmune modulator and a potential target for treating inflammatory pain.
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Affiliation(s)
- Dustin P Green
- The Solomon H. Snyder Department of Neuroscience, Center for Sensory Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Nathachit Limjunyawong
- The Solomon H. Snyder Department of Neuroscience, Center for Sensory Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Naina Gour
- The Solomon H. Snyder Department of Neuroscience, Center for Sensory Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Priyanka Pundir
- The Solomon H. Snyder Department of Neuroscience, Center for Sensory Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Xinzhong Dong
- The Solomon H. Snyder Department of Neuroscience, Center for Sensory Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA; Howard Hughes Medical Institute, Johns Hopkins University, Baltimore, MD, USA.
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55
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Hunyady Á, Hajna Z, Gubányi T, Scheich B, Kemény Á, Gaszner B, Borbély É, Helyes Z. Hemokinin-1 is an important mediator of pain in mouse models of neuropathic and inflammatory mechanisms. Brain Res Bull 2019; 147:165-173. [PMID: 30664920 DOI: 10.1016/j.brainresbull.2019.01.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 01/11/2019] [Accepted: 01/14/2019] [Indexed: 01/15/2023]
Abstract
The Tac4 gene-derived hemokinin-1 (HK-1) is present in pain-related regions and activates the tachykinin NK1 receptor, but with binding site and signaling pathways different from Substance P (SP). NK1 receptor is involved in nociception, but our earlier data showed that it has no role in chronic neuropathic hyperalgesia, similarly to SP. Furthermore, NK1 antagonists failed in clinical trials as analgesics due to still unknown reasons. Therefore, we investigated the role of HK-1 in pain conditions of distinct mechanisms using genetically modified mice. Chronic neuropathic mechanical and cold hyperalgesia after partial sciatic nerve ligation (PSL) were determined by dynamic plantar aesthesiometry and withdrawal latency from icy water, motor coordination on the accelerating Rotarod. Peripheral nerve growth factor (NGF) production was measured by ELISA, neuronal and glia cell activation by immunohistochemistry in pain-related regions. Acute somatic and visceral chemonocifensive behaviors were assessed after intraplantar formalin or intraperitoneal acetic-acid injection, respectively. Resiniferatoxin-induced inflammatory mechanical and thermal hyperalgesia by aesthesiometry and increasing temperature hot plate. Chronic neuropathic mechanical and cold hypersensitivity were significantly decreased in HK-1 deficient mice. NGF level in the paw homogenates of intact mice were significantly lower in case of HK-1 deletion. However, it significantly increased under neuropathic condition in contrast to wildtype mice, where the higher basal concentration did not show any changes. Microglia, but not astrocyte activation was observed 14 days after PSL in the ipsilateral spinal dorsal horn of wildtype, but not HK-1-deficient mice. However, under neuropathic conditions, the number of GFAP-positive astrocytes was significantly smaller in case of HK-1 deletion. Acute visceral, but not somatic nocifensive behavior, as well as neurogenic inflammatory mechanical and thermal hypersensitivity were significantly reduced by HK-1 deficiency similarly to NK1, but not to SP deletion. We provide evidence for pro-nociceptive role of HK-1, via NK1 receptor activation in acute inflammation models, but differently from SP-mediated actions. Identification of its targets and signaling can open new directions in pain research.
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Affiliation(s)
- Ágnes Hunyady
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Hungary; János Szentágothai Research Centre, Centre for Neuroscience, University of Pécs, Hungary
| | - Zsófia Hajna
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Hungary; János Szentágothai Research Centre, Centre for Neuroscience, University of Pécs, Hungary
| | - Tímea Gubányi
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Hungary; János Szentágothai Research Centre, Centre for Neuroscience, University of Pécs, Hungary
| | - Bálint Scheich
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Hungary; János Szentágothai Research Centre, Centre for Neuroscience, University of Pécs, Hungary
| | - Ágnes Kemény
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Hungary; János Szentágothai Research Centre, Centre for Neuroscience, University of Pécs, Hungary; Department of Medical Biology, Medical School, University of Pécs, Hungary
| | - Balázs Gaszner
- Department of Anatomy, Medical School, University of Pécs, Hungary
| | - Éva Borbély
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Hungary; János Szentágothai Research Centre, Centre for Neuroscience, University of Pécs, Hungary
| | - Zsuzsanna Helyes
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Hungary; János Szentágothai Research Centre, Centre for Neuroscience, University of Pécs, Hungary.
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56
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Rice FL, Castel D, Ruggiero E, Dockum M, Houk G, Sabbag I, Albrecht PJ, Meilin S. Human-like cutaneous neuropathologies associated with a porcine model of peripheral neuritis: A translational platform for neuropathic pain. NEUROBIOLOGY OF PAIN (CAMBRIDGE, MASS.) 2019; 5:100021. [PMID: 31194066 PMCID: PMC6550106 DOI: 10.1016/j.ynpai.2018.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/19/2018] [Accepted: 07/19/2018] [Indexed: 01/10/2023]
Abstract
Despite enormous investment in research and development of novel treatments, there remains a lack of predictable, effective, and safe therapeutics for human chronic neuropathic pain (NP) afflictions. NP continues to increase among the population and treatments remain a major unmet public health care need. In recent years, numerous costly (time and money) failures have occurred attempting to translate successful animal pain model results, typically using rodents, to human clinical trials. These continued failures point to the essential need for better animal models of human pain conditions. To address this challenge, we have previously developed a peripheral neuritis trauma (PNT) model of chronic pain induced by a proximal sciatic nerve irritation in pigs, which have a body size, metabolism, skin structure, and cutaneous innervation more similar to humans. Here, we set out to determine the extent that the PNT model presents with cutaneous neuropathologies consistent with those associated with human chronic NP afflictions. Exactly as is performed in human skin biopsies, extensive quantitative multi-molecular immunofluorescence analyses of porcine skin biopsies were performed to assess cutaneous innervation and skin structure. ChemoMorphometric Analysis (CMA) results demonstrated a significant reduction in small caliber intraepidermal nerve fiber (IENF) innervation, altered dermal vascular innervation, and aberrant analgesic/algesic neurochemical properties among epidermal keratinocytes, which are implicated in modulating sensory innervation. These comprehensive pathologic changes very closely resemble those observed from CMA of human skin biopsies collected from NP afflictions. The results indicate that the porcine PNT model is more appropriate for translational NP research compared with commonly utilized rodent models. Because the PNT model creates cutaneous innervation and keratinocyte immunolabeling alterations consistent with human NP conditions, use of this animal model for NP testing and treatment response characteristics will likely provide more realistic results to direct successful translation to humans.
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Affiliation(s)
- Frank L. Rice
- Neuroscience & Pain Research Group, Integrated Tissue Dynamics, LLC, Rensselaer, NY 12144, United States
- Division of Health Sciences, University at Albany, Rensselaer, NY 12144, United States
| | - David Castel
- The Neufeld Cardiac Research Institute, Sheba Medical Centre, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - Elizabeth Ruggiero
- Neuroscience & Pain Research Group, Integrated Tissue Dynamics, LLC, Rensselaer, NY 12144, United States
| | - Marilyn Dockum
- Neuroscience & Pain Research Group, Integrated Tissue Dynamics, LLC, Rensselaer, NY 12144, United States
| | - George Houk
- Neuroscience & Pain Research Group, Integrated Tissue Dynamics, LLC, Rensselaer, NY 12144, United States
| | - Itai Sabbag
- Lahav Research Institute, Kibutz Lahav, Negev 85335, Israel
| | - Phillip J. Albrecht
- Neuroscience & Pain Research Group, Integrated Tissue Dynamics, LLC, Rensselaer, NY 12144, United States
- Division of Health Sciences, University at Albany, Rensselaer, NY 12144, United States
| | - Sigal Meilin
- MD Biosciences, Neurology R&D Division, Nes-Ziona 74140, Israel
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57
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Gutierrez S, Alvarado-Vázquez PA, Eisenach JC, Romero-Sandoval EA, Boada MD. Tachykinins modulate nociceptive responsiveness and sensitization: In vivo electrical characterization of primary sensory neurons in tachykinin knockout (Tac1 KO) mice. Mol Pain 2019; 15:1744806919845750. [PMID: 31012376 PMCID: PMC6505240 DOI: 10.1177/1744806919845750] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 03/21/2019] [Accepted: 03/22/2019] [Indexed: 01/08/2023] Open
Abstract
Since the failure of specific substance P antagonists to induce analgesia, the role of tachykinins in the development of neuropathic pain states has been discounted. This conclusion was reached without studies on the role of tachykinins in normal patterns of primary afferents response and sensitization or the consequences of their absence on the modulation of primary mechanonociceptive afferents after injury. Nociceptive afferents from animals lacking tachykinins (Tac1 knockout) showed a disrupted pattern of activation to tonic suprathreshold mechanical stimulation. These nociceptors failed to encode the duration and magnitude of natural pronociceptive stimuli or to develop mechanical sensitization as consequence of this stimulation. Moreover, paw edema, hypersensitivity, and weight bearing were also reduced in Tac1 knockout mice 24 h after paw incision surgery. At this time, nociceptive afferents from these animals did not show the normal sensitization to mechanical stimulation or altered membrane electrical hyperexcitability as observed in wild-type animals. These changes occurred despite a similar increase in calcitonin gene-related peptide immunoreactivity in sensory neurons in Tac1 knockout and normal mice. Based on these observations, we conclude that tachykinins are critical modulators of primary nociceptive afferents, with a preeminent role in the electrical control of their excitability with sustained activation or injury.
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Affiliation(s)
| | | | | | | | - M Danilo Boada
- Wake Forest Baptist Medical Center, Winston-Salem, NC, USA
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58
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Hökfelt T, Barde S, Xu ZQD, Kuteeva E, Rüegg J, Le Maitre E, Risling M, Kehr J, Ihnatko R, Theodorsson E, Palkovits M, Deakin W, Bagdy G, Juhasz G, Prud’homme HJ, Mechawar N, Diaz-Heijtz R, Ögren SO. Neuropeptide and Small Transmitter Coexistence: Fundamental Studies and Relevance to Mental Illness. Front Neural Circuits 2018; 12:106. [PMID: 30627087 PMCID: PMC6309708 DOI: 10.3389/fncir.2018.00106] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 11/05/2018] [Indexed: 12/31/2022] Open
Abstract
Neuropeptides are auxiliary messenger molecules that always co-exist in nerve cells with one or more small molecule (classic) neurotransmitters. Neuropeptides act both as transmitters and trophic factors, and play a role particularly when the nervous system is challenged, as by injury, pain or stress. Here neuropeptides and coexistence in mammals are reviewed, but with special focus on the 29/30 amino acid galanin and its three receptors GalR1, -R2 and -R3. In particular, galanin's role as a co-transmitter in both rodent and human noradrenergic locus coeruleus (LC) neurons is addressed. Extensive experimental animal data strongly suggest a role for the galanin system in depression-like behavior. The translational potential of these results was tested by studying the galanin system in postmortem human brains, first in normal brains, and then in a comparison of five regions of brains obtained from depressed people who committed suicide, and from matched controls. The distribution of galanin and the four galanin system transcripts in the normal human brain was determined, and selective and parallel changes in levels of transcripts and DNA methylation for galanin and its three receptors were assessed in depressed patients who committed suicide: upregulation of transcripts, e.g., for galanin and GalR3 in LC, paralleled by a decrease in DNA methylation, suggesting involvement of epigenetic mechanisms. It is hypothesized that, when exposed to severe stress, the noradrenergic LC neurons fire in bursts and release galanin from their soma/dendrites. Galanin then acts on somato-dendritic, inhibitory galanin autoreceptors, opening potassium channels and inhibiting firing. The purpose of these autoreceptors is to act as a 'brake' to prevent overexcitation, a brake that is also part of resilience to stress that protects against depression. Depression then arises when the inhibition is too strong and long lasting - a maladaption, allostatic load, leading to depletion of NA levels in the forebrain. It is suggested that disinhibition by a galanin antagonist may have antidepressant activity by restoring forebrain NA levels. A role of galanin in depression is also supported by a recent candidate gene study, showing that variants in genes for galanin and its three receptors confer increased risk of depression and anxiety in people who experienced childhood adversity or recent negative life events. In summary, galanin, a neuropeptide coexisting in LC neurons, may participate in the mechanism underlying resilience against a serious and common disorder, MDD. Existing and further results may lead to an increased understanding of how this illness develops, which in turn could provide a basis for its treatment.
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Affiliation(s)
- Tomas Hökfelt
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Swapnali Barde
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Zhi-Qing David Xu
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Department of Neurobiology, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Laboratory of Brain Disorders (Ministry of Science and Technology), Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Eugenia Kuteeva
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Joelle Rüegg
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
- The Center for Molecular Medicine, Stockholm, Sweden
- Swedish Toxicology Sciences Research Center, Swetox, Södertälje, Sweden
| | - Erwan Le Maitre
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Mårten Risling
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Jan Kehr
- Pronexus Analytical AB, Solna, Sweden
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Robert Ihnatko
- Department of Clinical Chemistry, Linköping University, Linköping, Sweden
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Elvar Theodorsson
- Department of Clinical Chemistry, Linköping University, Linköping, Sweden
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Miklos Palkovits
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
| | - William Deakin
- Neuroscience and Psychiatry Unit, University of Manchester, Manchester, United Kingdom
| | - Gyorgy Bagdy
- Department of Pharmacodynamics, Semmelweis University, Budapest, Hungary
- MTA-SE Neuropsychopharmacology and Neurochemistry Research Group, Hungarian Academy of Sciences, Semmelweis University, Budapest, Hungary
- NAP 2-SE New Antidepressant Target Research Group, Hungarian Brain Research Program, Semmelweis University, Budapest, Hungary
| | - Gabriella Juhasz
- Neuroscience and Psychiatry Unit, University of Manchester, Manchester, United Kingdom
- Department of Pharmacodynamics, Semmelweis University, Budapest, Hungary
- SE-NAP2 Genetic Brain Imaging Migraine Research Group, Hungarian Brain Research Program, Semmelweis University, Budapest, Hungary
| | | | - Naguib Mechawar
- Douglas Hospital Research Centre, Verdun, QC, Canada
- Department of Psychiatry, McGill University, Montreal, QC, Canada
| | | | - Sven Ove Ögren
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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Abstract
Hybrid compounds (also known as chimeras, designed multiple ligands, bivalent compounds) are chemical units where two active components, usually possessing affinity and selectivity for distinct molecular targets, are combined as a single chemical entity. The rationale for using a chimeric approach is well documented as such novel drugs are characterized by their enhanced enzymatic stability and biological activity. This allows their use at lower concentrations, increasing their safety profile, particularly when considering undesirable side effects. In the group of synthetic bivalent compounds, drugs combining pharmacophores having affinities toward opioid and neurokinin-1 receptors have been extensively studied as potential analgesic drugs. Indeed, substance P is known as a major endogenous modulator of nociception both in the peripheral and central nervous systems. Hence, synthetic peptide fragments showing either agonism or antagonism at neurokinin 1 receptor were both assigned with analgesic properties. However, even though preclinical studies designated neurokinin-1 receptor antagonists as promising analgesics, early clinical studies revealed a lack of efficacy in human. Nevertheless, their molecular combination with enkephalin/endomorphin fragments has been considered as a valuable approach to design putatively promising ligands for the treatment of pain. This paper is aimed at summarizing a 20-year journey to the development of potent analgesic hybrid compounds involving an opioid pharmacophore and devoid of unwanted side effects. Additionally, the legitimacy of considering neurokinin-1 receptor ligands in the design of chimeric drugs is discussed.
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60
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Birklein F, Ibrahim A, Schlereth T, Kingery WS. The Rodent Tibia Fracture Model: A Critical Review and Comparison With the Complex Regional Pain Syndrome Literature. THE JOURNAL OF PAIN 2018; 19:1102.e1-1102.e19. [PMID: 29684510 PMCID: PMC6163066 DOI: 10.1016/j.jpain.2018.03.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 02/28/2018] [Accepted: 03/30/2018] [Indexed: 12/23/2022]
Abstract
Distal limb fracture is the most common cause of complex regional pain syndrome (CRPS), thus the rodent tibia fracture model (TFM) was developed to study CRPS pathogenesis. This comprehensive review summarizes the published TFM research and compares these experimental results with the CRPS literature. The TFM generated spontaneous and evoked pain behaviors, inflammatory symptoms (edema, warmth), and trophic changes (skin thickening, osteoporosis) resembling symptoms in early CRPS. Neuropeptides, inflammatory cytokines, and nerve growth factor (NGF) have been linked to pain behaviors, inflammation, and trophic changes in the TFM model and proliferating keratinocytes were identified as the primary source of cutaneous cytokines and NGF. Tibia fracture also activated spinal glia and upregulated spinal neuropeptide, cytokine, and NGF expression, and in the brain it changed dendritic architecture. B cell-expressed immunoglobulin M antibodies also contributed to pain behavior, indicating a role for adaptive immunity. These results modeled many findings in early CRPS, but significant differences were also noted. PERSPECTIVE Multiple neuroimmune signaling mechanisms contribute to the pain, inflammation, and trophic changes observed in the injured limb of the rodent TFM. This model replicates many of the symptoms, signs, and pathophysiology of early CRPS, but most post-fracture changes resolve within 5 months and may not contribute to perpetuating chronic CRPS.
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Affiliation(s)
- Frank Birklein
- University Medical Center of the Johannes Gutenberg University Mainz, Department of Neurology, Mainz, Germany
| | - Alaa Ibrahim
- University Medical Center of the Johannes Gutenberg University Mainz, Department of Neurology, Mainz, Germany
| | - Tanja Schlereth
- University Medical Center of the Johannes Gutenberg University Mainz, Department of Neurology, Mainz, Germany
| | - Wade S Kingery
- Palo Alto Veterans Institute for Research, Veterans Affairs Palo Alto Health Care System, Palo Alto, California.
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61
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Sanger GJ, Andrews PLR. A History of Drug Discovery for Treatment of Nausea and Vomiting and the Implications for Future Research. Front Pharmacol 2018; 9:913. [PMID: 30233361 PMCID: PMC6131675 DOI: 10.3389/fphar.2018.00913] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 07/25/2018] [Indexed: 12/24/2022] Open
Abstract
The origins of the major classes of current anti-emetics are examined. Serendipity is a recurrent theme in discovery of their anti-emetic properties and repurposing from one indication to another is a continuing trend. Notably, the discoveries have occurred against a background of company mergers and changing anti-emetic requirements. Major drug classes include: (i) Muscarinic receptor antagonists-originated from historical accounts of plant extracts containing atropine and hyoscine with development stimulated by the need to prevent sea-sickness among soldiers during beach landings; (ii) Histamine receptor antagonists-searching for replacements for the anti-malaria drug quinine, in short supply because of wartime shipping blockade, facilitated the discovery of histamine (H1) antagonists (e.g., dimenhydrinate), followed by serendipitous discovery of anti-emetic activity against motion sickness in a patient undergoing treatment for urticaria; (iii) Phenothiazines and dopamine receptor antagonists-investigations of their pharmacology as "sedatives" (e.g., chlorpromazine) implicated dopamine receptors in emesis, leading to development of selective dopamine (D2) receptor antagonists (e.g., domperidone with poor ability to penetrate the blood-brain barrier) as anti-emetics in chemotherapy and surgery; (iv) Metoclopramide and selective 5-hydroxytryptamine3(5-HT3) receptor antagonists-metoclopramide was initially assumed to act only via D2 receptor antagonism but subsequently its gastric motility stimulant effect (proposed to contribute to the anti-emetic action) was shown to be due to 5-hydroxytryptamine4 receptor agonism. Pre-clinical studies showed that anti-emetic efficacy against the newly-introduced, highly emetic, chemotherapeutic agent cisplatin was due to antagonism at 5-HT3 receptors. The latter led to identification of selective 5-HT3 receptor antagonists (e.g., granisetron), a major breakthrough in treatment of chemotherapy-induced emesis; (v) Neurokinin1receptor antagonists-antagonists of the actions of substance P were developed as analgesics but pre-clinical studies identified broad-spectrum anti-emetic effects; clinical studies showed particular efficacy in the delayed phase of chemotherapy-induced emesis. Finally, the repurposing of different drugs for treatment of nausea and vomiting is examined, particularly during palliative care, and also the challenges in identifying novel anti-emetic drugs, particularly for treatment of nausea as compared to vomiting. We consider the lessons from the past for the future and ask why there has not been a major breakthrough in the last 20 years.
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Affiliation(s)
- Gareth J. Sanger
- Blizard Institute and the National Centre for Bowel Research, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Paul L. R. Andrews
- Division of Biomedical Sciences, St George's University of London, London, United Kingdom
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Iadarola MJ, Sapio MR, Wang X, Carrero H, Virata-Theimer ML, Sarnovsky R, Mannes AJ, FitzGerald DJ. Analgesia by Deletion of Spinal Neurokinin 1 Receptor Expressing Neurons Using a Bioengineered Substance P-Pseudomonas Exotoxin Conjugate. Mol Pain 2018; 13:1744806917727657. [PMID: 28814145 PMCID: PMC5574484 DOI: 10.1177/1744806917727657] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Cell deletion approaches to pain directed at either the primary nociceptive afferents or
second-order neurons are highly effective analgesic manipulations. Second-order spinal
neurons expressing the neurokinin 1 (NK1) receptor are required for the perception of many
types of pain. To delete NK1+ neurons for the purpose of pain control, we generated a
toxin–peptide conjugate using DTNB-derivatized (Cys0) substance P (SP) and a
N-terminally truncated Pseudomonas exotoxin (PE35) that retains the endosome-release and
ADP-ribosylation enzymatic domains but with only one free sulfhydryl side chain for
conjugation. This allowed generation of a one-to-one product linked by a disulfide bond
(SP-PE35). In vitro, Chinese hamster ovary cells stably transfected with the NK1 receptor
exhibited specific cytotoxicity when exposed to SP-PE35
(IC50 = 5 × 10−11 M), whereas the conjugate was nontoxic to NK2
and NK3 receptor-bearing cell lines. In vivo studies showed that, after infusion into the
spinal subarachnoid space, the toxin was extremely effective in deleting NK1
receptor-expressing cells from the dorsal horn of the spinal cord. The specific cell
deletion robustly attenuated thermal and mechanical pain sensations and inflammatory
hyperalgesia but did not affect motoric capabilities. NK1 receptor cell deletion and
antinociception occurred without obvious lesion of non–receptor-expressing cells or
apparent reorganization of primary afferent innervation. These data demonstrate the
extraordinary selectivity and broad-spectrum antinociceptive efficacy of this
ligand-directed protein therapeutic acting via receptor-mediated endocytosis. The loss of
multiple pain modalities including heat and mechanical pinch, transduced by different
populations of primary afferents, shows that spinal NK1 receptor-expressing neurons are
critical points of convergence in the nociceptive transmission circuit. We further suggest
that therapeutic end points can be effectively and safely achieved when SP-PE35 is locally
infused, thereby producing a regionally defined analgesia.
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Affiliation(s)
- Michael J Iadarola
- Department of Perioperative Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20892
| | | | - Xunde Wang
- Biotherapy Section, Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - Hector Carrero
- Pain and Neurosensory Mechanisms Branch, National Institutes of Dental and Craniofacial
| | - Maria Luisa Virata-Theimer
- Biotherapy Section, Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - Robert Sarnovsky
- Biotherapy Section, Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - Andrew J Mannes
- Department of Perioperative Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20892
| | - David J FitzGerald
- Biotherapy Section, Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
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Diaz-delCastillo M, Woldbye DP, Heegaard AM. Neuropeptide Y and its Involvement in Chronic Pain. Neuroscience 2018; 387:162-169. [DOI: 10.1016/j.neuroscience.2017.08.050] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 08/22/2017] [Accepted: 08/29/2017] [Indexed: 12/20/2022]
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Neuroepithelial control of mucosal inflammation in acute cystitis. Sci Rep 2018; 8:11015. [PMID: 30030504 PMCID: PMC6054610 DOI: 10.1038/s41598-018-28634-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 05/03/2018] [Indexed: 12/18/2022] Open
Abstract
The nervous system is engaged by infection, indirectly through inflammatory cascades or directly, by bacterial attack on nerve cells. Here we identify a neuro-epithelial activation loop that participates in the control of mucosal inflammation and pain in acute cystitis. We show that infection activates Neurokinin-1 receptor (NK1R) and Substance P (SP) expression in nerve cells and bladder epithelial cells in vitro and in vivo in the urinary bladder mucosa. Specific innate immune response genes regulated this mucosal response, and single gene deletions resulted either in protection (Tlr4−/− and Il1b−/− mice) or in accentuated bladder pathology (Asc−/− and Nlrp3−/− mice), compared to controls. NK1R/SP expression was lower in Tlr4−/− and Il1b−/− mice than in C56BL/6WT controls but in Asc−/− and Nlrp3−/− mice, NK1R over-activation accompanied the exaggerated disease phenotype, due, in part to transcriptional de-repression of Tacr1. Pharmacologic NK1R inhibitors attenuated acute cystitis in susceptible mice, supporting a role in disease pathogenesis. Clinical relevance was suggested by elevated urine SP levels in patients with acute cystitis, compared to patients with asymptomatic bacteriuria identifying NK1R/SP as potential therapeutic targets. We propose that NK1R and SP influence the severity of acute cystitis through a neuro-epithelial activation loop that controls pain and mucosal inflammation.
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Zak A, Siwinska N, Slowikowska M, Borowicz H, Szpot P, Zawadzki M, Niedzwiedz A. The detection of capsaicin and dihydrocapsaicin in horse serum following long-term local administration. BMC Vet Res 2018; 14:193. [PMID: 29914499 PMCID: PMC6006555 DOI: 10.1186/s12917-018-1518-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 06/06/2018] [Indexed: 11/21/2022] Open
Abstract
Background Capsaicin and dihydrocapsaicin are alkaloids with analgesic effects in humans and animals. When used locally, both of them minimalise pain sensation by defunctionalising nerve endings. According to the Federation Equestrian International Prohibited Substances List, these are substance banned in horse competitions. The aim of the study was to determine the detection time of capsaicin in both plasma and serum after long-term use of a gel recommended for commercial use and applied as intended. The objective of the study was to select the best material for the detection of capsaicin as a doping substance in horses. Methods Nine healthy mature horses were administered 0.1% capsaicin topically in the form of a commercial analgesic gel (15 g of the gel per limb) to the front limbs every 24 hours for five days with a polar fleece bandage. Blood serum and plasma were collected prior to gel application and in the 12th, 18th, 24th, 36th, 42nd, 48th, 60th, 84th, 108th, 132nd, 156th hour after the gel application. Qualitative and quantitative analysis was performed using ultra-high performance liquid chromatography coupled with a triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS). Results The concentration of capsaicin in the serum samples did not exceed the lower limit of quantification. Capsaicin was not detected in the plasma samples during the entire study period. Dihydrocapsaicin was not detected in blood serum or plasma. Conclusion The presented results suggest that capsaicin is not detected in horse serum in the 24-hour-periodfollowing its last application according to the dosage regimen used by owners and veterinarians for therapy rather than doping, based on a five day gel application and a polar bandage.
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Affiliation(s)
- A Zak
- Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 47, 50-366, Wroclaw, Poland.
| | - N Siwinska
- Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 47, 50-366, Wroclaw, Poland
| | - M Slowikowska
- Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 47, 50-366, Wroclaw, Poland
| | - H Borowicz
- Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 47, 50-366, Wroclaw, Poland
| | - P Szpot
- Department of Forensic Medicine, Wroclaw Medical University, ul. Mikulicza-Radeckiego 4, 50-345, Wroclaw, Poland
| | - M Zawadzki
- Department of Forensic Medicine, Wroclaw Medical University, ul. Mikulicza-Radeckiego 4, 50-345, Wroclaw, Poland
| | - A Niedzwiedz
- Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 47, 50-366, Wroclaw, Poland
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Yezierski RP, Hansson P. Inflammatory and Neuropathic Pain From Bench to Bedside: What Went Wrong? THE JOURNAL OF PAIN 2018; 19:571-588. [DOI: 10.1016/j.jpain.2017.12.261] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 11/29/2017] [Accepted: 12/13/2017] [Indexed: 12/31/2022]
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Ryan NM, Vertigan AE, Birring SS. An update and systematic review on drug therapies for the treatment of refractory chronic cough. Expert Opin Pharmacother 2018; 19:687-711. [PMID: 29658795 PMCID: PMC5935050 DOI: 10.1080/14656566.2018.1462795] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 04/05/2018] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Chronic Cough (CC) is common and often associated with significant comorbidity and decreased quality of life. In up to 50% of cases, the cough is refractory despite extensive investigation and treatment trials. It is likely that the key abnormality in refractory CC is dysfunctional, hypersensitive sensory nerves, similar to conditions such as laryngeal hypersensitivity and neuropathic pain. AREAS COVERED The aim of this systematic review is to assess drug therapies for refractory CC. The authors review the current management of CC and provide discussion of the similarities between neuropathic pain and refractory CC. They review repurposed and new pharmacological treatments. Several meta-analyses were performed to compare the efficacy of treatments where possible. EXPERT OPINION Repurposed pain medications such as gabapentin and pregabalin reduce the frequency of cough and improve quality of life. Along with speech pathology, they are important and alternate treatments for refractory CC. However, more treatments are needed and the P2X3 ion channel receptor antagonists show the most promise. With a better understanding of neuronal activation and sensitisation and their signal processing in the brain, improved animal models of cough, and the use of validated cough measurement tools, more effective treatments will develop.
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Affiliation(s)
- Nicole M. Ryan
- Clinical Toxicology Research Group, School of Medicine and Public Health, The University of Newcastle, Calvary Mater Hospital, Newcastle, Australia
| | - Anne E. Vertigan
- Centre for Asthma and Respiratory Diseases, School of Medicine and Public Health, Hunter Medical Research Institute, The University of Newcastle, Newcastle, Australia
- Department of Speech Pathology, John Hunter Hospital, Hunter New England Health, Newcastle, Australia
| | - Surinder S. Birring
- Division of Asthma, Allergy & Lung Biology, School of Transplantation, Immunology, Infection & Inflammation Sciences, Faculty of Life Sciences & Medicine, King’s College London, London, UK
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A historical perspective on the role of sensory nerves in neurogenic inflammation. Semin Immunopathol 2018; 40:229-236. [PMID: 29616309 PMCID: PMC5960476 DOI: 10.1007/s00281-018-0673-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 03/06/2018] [Indexed: 01/25/2023]
Abstract
The term ‘neurogenic inflammation’ is commonly used, especially with respect to the role of sensory nerves within inflammatory disease. However, despite over a century of research, we remain unclear about the role of these nerves in the vascular biology of inflammation, as compared with their interacting role in pain processing and of their potential for therapeutic manipulation. This chapter attempts to discuss the progress in understanding, from the initial discovery of sensory nerves until the present day. This covers pioneering findings that these nerves exist, are involved in vascular events and act as important sensors of environmental changes, including injury and infection. This is followed by discovery of the contents they release such as the established vasoactive neuropeptides substance P and CGRP as well as anti-inflammatory peptides such as the opioids and somatostatin. The more recent emergence of the importance of the transient receptor potential (TRP) channels has revealed some of the mechanisms by which these nerves sense environmental stimuli. This knowledge enables a platform from which to learn of the potential role of neurogenic inflammation in disease and in turn of novel therapeutic targets.
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Negus SS. Addressing the Opioid Crisis: The Importance of Choosing Translational Endpoints in Analgesic Drug Discovery. Trends Pharmacol Sci 2018; 39:327-330. [PMID: 29501211 DOI: 10.1016/j.tips.2018.02.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 02/06/2018] [Indexed: 11/19/2022]
Abstract
The opioid crisis has stimulated renewed interest in analgesic drug development. This effort will involve preclinical-to-clinical translational research and will benefit from a focus on endpoints that are both clinically relevant and shared across laboratory animals and humans. Measures of pain-related functional impairment and behavioral depression could serve this purpose.
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Affiliation(s)
- S Stevens Negus
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond VA, USA.
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Lascelles BDX, Brown DC, Maixner W, Mogil JS. Spontaneous painful disease in companion animals can facilitate the development of chronic pain therapies for humans. Osteoarthritis Cartilage 2018; 26:175-183. [PMID: 29180098 DOI: 10.1016/j.joca.2017.11.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 10/17/2017] [Accepted: 11/13/2017] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To outline the role that spontaneous osteoarthritis (OA) in companion animals can play in translational research and therapeutic pharmacological development. OUTLINE Narrative review summarizing the opportunities and limitations of naturally occurring, spontaneous OA as models of human OA pain, with a focus on companion animal pets. The background leading to considering inserting spontaneous disease models in the translational paradigm is provided. The utility of this model is discussed in terms of outcome measures that have been validated as being related to pain, and in terms of the potential for target discovery is outlined. The limitations to using companion animal pets as models of human disease are discussed. CONCLUSIONS Although many steps along the translational drug development pathway have been identified as needing improvement, spontaneous painful OA in companion animals offers translational potential. Such 'models' may better reflect the complex genetic, environmental, temporal and physiological influences present in humans and current data suggests the predictive validity of the models are good. The opportunity for target discovery exists but is, as yet, unproven.
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Affiliation(s)
- B D X Lascelles
- Comparative Pain Research Program, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC, USA; Center for Pain Research and Innovation, UNC School of Dentistry, Chapel Hill, NC, USA; Center for Translational Pain Research, Department of Anesthesiology, Duke University, Durham, NC, USA.
| | - D C Brown
- Translational Comparative Medicine Research, Elanco Animal Health, Greenfield, IN, USA
| | - W Maixner
- Center for Translational Pain Research, Department of Anesthesiology, Duke University, Durham, NC, USA
| | - J S Mogil
- Department of Psychology, Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada; Department of Anesthesia, Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada
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Latremoliere A, Costigan M. Combining Human and Rodent Genetics to Identify New Analgesics. Neurosci Bull 2018; 34:143-155. [PMID: 28667479 PMCID: PMC5799129 DOI: 10.1007/s12264-017-0152-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Accepted: 06/01/2017] [Indexed: 12/26/2022] Open
Abstract
Most attempts at rational development of new analgesics have failed, in part because chronic pain involves multiple processes that remain poorly understood. To improve translational success, one strategy is to select novel targets for which there is proof of clinical relevance, either genetically through heritable traits, or pharmacologically. Such an approach by definition yields targets with high clinical validity. The biology of these targets can be elucidated in animal models before returning to the patients with a refined therapeutic. For optimal treatment, having biomarkers of drug action available is also a plus. Here we describe a case study in rational drug design: the use of controlled inhibition of peripheral tetrahydrobiopterin (BH4) synthesis to reduce abnormal chronic pain states without altering nociceptive-protective pain. Initially identified in a population of patients with low back pain, the association between BH4 production and chronic pain has been confirmed in more than 12 independent cohorts, through a common haplotype (present in 25% of Caucasians) of the rate-limiting enzyme for BH4 synthesis, GTP cyclohydrolase 1 (GCH1). Genetic tools in mice have demonstrated that both injured sensory neurons and activated macrophages engage increased BH4 synthesis to cause chronic pain. GCH1 is an obligate enzyme for de novo BH4 production. Therefore, inhibiting GCH1 activity eliminates all BH4 production, affecting the synthesis of multiple neurotransmitters and signaling molecules and interfering with physiological function. In contrast, targeting the last enzyme of the BH4 synthesis pathway, sepiapterin reductase (SPR), allows reduction of pathological BH4 production without completely blocking physiological BH4 synthesis. Systemic SPR inhibition in mice has not revealed any safety concerns to date, and available genetic and pharmacologic data suggest similar responses in humans. Finally, because it is present in vivo only when SPR is inhibited, sepiapterin serves as a reliable biomarker of target engagement, allowing potential quantification of drug efficacy. The emerging development of therapeutics that target BH4 synthesis to treat chronic pain illustrates the power of combining human and mouse genetics: human genetic studies for clinical selection of relevant targets, coupled with causality studies in mice, allowing the rational engineering of new analgesics.
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Affiliation(s)
- Alban Latremoliere
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA, 02115, USA.
| | - Michael Costigan
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA, 02115, USA.
- Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Boston, MA, 02115, USA.
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Manorak W, Idahosa C, Gupta K, Roy S, Panettieri R, Ali H. Upregulation of Mas-related G Protein coupled receptor X2 in asthmatic lung mast cells and its activation by the novel neuropeptide hemokinin-1. Respir Res 2018; 19:1. [PMID: 29295703 PMCID: PMC5751818 DOI: 10.1186/s12931-017-0698-3] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Accepted: 12/11/2017] [Indexed: 12/21/2022] Open
Abstract
Hemokinin-1 (HK-1) is a novel neuropeptide produced by human bronchial cells and macrophages and causes contraction of human bronchi ex vivo. It is also generated by antigen/IgE-activated murine mast cells (MCs) and contributes to experimental chronic allergic airway inflammation via the activation of the neurokinin receptor-1 (NK-1R) expressed on murine MCs. We found elevated MC numbers in the lungs of individuals who died from asthma (asthma) when compared to lungs of individuals who died from other causes (non-asthma). Mas-related G Protein coupled receptor X2 (MRGPRX2) is a novel G-protein coupled receptor (GPCR) that is expressed predominantly on human MCs. We detected low level of MRGPRX2 in non-asthma lung MCs but its expression was significantly upregulated in asthma lung MCs. HK-1 caused degranulation in a human MC line (LAD2) and RBL-2H3 cells stably expressing MRGPRX2 and this response was resistant to inhibition by an NK-1R antagonist. However, knockdown of MRGPRX2 in LAD2 cells resulted in substantial inhibition of HK-1-induced degranulation. These findings suggest that while HK-1 contributes to the development of experimental asthma in mice via NK-1R on murine MCs the effect of this neuropeptide on human bronchoconstriction likely reflects the activation of MRGPRX2 on lung MCs. Thus, development of selective MRGPRX2 antagonists could serve as novel target for the modulation of asthma.
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Affiliation(s)
- Wichayapha Manorak
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Philadelphia, PA, 19104-6030, USA
| | - Chizobam Idahosa
- Department of Oral Medicine, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Present Address: Departmentof Oral and Maxillofacial Pathology, Medicine and Surgery, Temple University Kornberg School of Dentistry, Philadelphia, PA, USA
| | - Kshitij Gupta
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Philadelphia, PA, 19104-6030, USA
| | - Saptarshi Roy
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Philadelphia, PA, 19104-6030, USA
| | - Reynold Panettieri
- Rutgers Institute for Translational Medicine and Science, Rutgers University, New Brunswick, NJ, USA
| | - Hydar Ali
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Philadelphia, PA, 19104-6030, USA.
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Pasricha PJ, Yates KP, Sarosiek I, McCallum RW, Abell TL, Koch KL, Nguyen LAB, Snape WJ, Hasler WL, Clarke JO, Dhalla S, Stein EM, Lee LA, Miriel LA, Van Natta ML, Grover M, Farrugia G, Tonascia J, Hamilton FA, Parkman HP. Aprepitant Has Mixed Effects on Nausea and Reduces Other Symptoms in Patients With Gastroparesis and Related Disorders. Gastroenterology 2018; 154:65-76.e11. [PMID: 29111115 PMCID: PMC5742047 DOI: 10.1053/j.gastro.2017.08.033] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 08/15/2017] [Accepted: 08/18/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS There are few effective treatments for nausea and other symptoms in patients with gastroparesis and related syndromes. We performed a randomized trial of the ability of the neurokinin-1 receptor antagonist aprepitant to reduce symptoms in patients with chronic nausea and vomiting caused by gastroparesis or gastroparesis-like syndrome. METHODS We conducted a 4-week multicenter, double-masked trial of 126 patients with at least moderate symptoms of chronic nausea and vomiting of presumed gastric origin for a minimum of 6 months. Patients were randomly assigned to groups given oral aprepitant (125 mg/day, n = 63) or placebo (n = 63). The primary outcome from the intention-to-treat analysis was reduction in nausea, defined as a decrease of 25 mm or more, or absolute level below 25 mm, on a daily patient-reported 0-to-100 visual analog scale (VAS) of nausea severity. We calculated relative risks of nausea improvement using stratified Cochran-Mental-Haenszel analysis. RESULTS Aprepitant did not reduce symptoms of nausea, based on the primary outcome measure (46% reduction in the VAS score in the aprepitant group vs 40% reduction in the placebo group; relative risk, 1.2; 95% CI, 0.8-1.7) (P = .43). However, patients in the aprepitant group had significant changes in secondary outcomes such as reduction in symptom severity (measured by the 0-5 Gastroparesis Clinical Symptom Index) for nausea (1.8 vs 1.0; P = .005), vomiting (1.6 vs 0.5; P = .001), and overall symptoms (1.3 vs 0.7; P = .001). Adverse events, predominantly mild or moderate in severity grade, were more common in aprepitant (22 of 63 patients, 35% vs 11 of 63, 17% in the placebo group) (P = .04). CONCLUSIONS In a randomized trial of patients with chronic nausea and vomiting caused by gastroparesis or gastroparesis-like syndrome, aprepitant did not reduce the severity of nausea when reduction in VAS score was used as the primary outcome. However, aprepitant had varying effects on secondary outcomes of symptom improvement. These findings support the need to identify appropriate patient outcomes for trials of therapies for gastroparesis, including potential additional trials for aprepitant. ClinicalTrials.gov no: NCT01149369.
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Affiliation(s)
| | - Katherine P Yates
- Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD
| | | | | | | | | | | | | | - William L Hasler
- Division of Gastroenterology, University of Michigan Health System, Ann Arbor, MI
| | - John O Clarke
- Johns Hopkins University School of Medicine, Baltimore, MD
| | - Sameer Dhalla
- Johns Hopkins University School of Medicine, Baltimore, MD
| | - Ellen M Stein
- Johns Hopkins University School of Medicine, Baltimore, MD
| | - Linda A Lee
- Johns Hopkins University School of Medicine, Baltimore, MD
| | - Laura A Miriel
- Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD
| | - Mark L Van Natta
- Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD
| | | | | | - James Tonascia
- Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD
| | - Frank A Hamilton
- National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD
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Rostock C, Schrenk-Siemens K, Pohle J, Siemens J. Human vs. Mouse Nociceptors - Similarities and Differences. Neuroscience 2017; 387:13-27. [PMID: 29229553 PMCID: PMC6150929 DOI: 10.1016/j.neuroscience.2017.11.047] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 10/30/2017] [Accepted: 11/29/2017] [Indexed: 02/09/2023]
Abstract
The somatosensory system allows us to detect a diverse range of physical and chemical stimuli including noxious ones, which can initiate protective reflexes to prevent tissue damage. However, the sensation of pain can - under pathological circumstances - outlive its usefulness and perpetrate ongoing suffering. Rodent model systems have been tremendously useful to help understand basic mechanisms of pain perception. Unfortunately, the translation of this knowledge into novel therapies has been challenging. We have investigated similarities and differences of human and mouse peptidergic (TRKA expressing) nociceptors using dual-color fluorescence in situ hybridization of dorsal root ganglia. By comparing the transcripts of a selected group of well-established nociceptive markers, we observed significant differences for some of them. We found co-expression of Trpv1, a key player for sensitization and inflammatory pain, with TrkA in a larger population in humans compared to mice. Similar results could be obtained for Nav1.8 and Nav1.9, two voltage gated sodium channels implicated in pathological forms of pain. Additionally, co-expression of Ret and TrkA was also found to be more abundant in human neurons. Moreover, the neurofilament heavy polypeptide was detected in all human sensory DRG neurons compared to a more selective expression pattern observed in rodents. To our knowledge, this is the first time that such detailed comparative analysis has been performed and we believe that our findings will direct future experimentation geared to understand the difficulties we face in translating findings from rodent models to humans.
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Affiliation(s)
- Charlotte Rostock
- Department of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Katrin Schrenk-Siemens
- Department of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Jörg Pohle
- Department of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Jan Siemens
- Department of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany.
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75
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Khasabov SG, Malecha P, Noack J, Tabakov J, Giesler GJ, Simone DA. Hyperalgesia and sensitization of dorsal horn neurons following activation of NK-1 receptors in the rostral ventromedial medulla. J Neurophysiol 2017; 118:2727-2744. [PMID: 28794197 PMCID: PMC5675905 DOI: 10.1152/jn.00478.2017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 08/04/2017] [Accepted: 08/06/2017] [Indexed: 11/22/2022] Open
Abstract
Neurons in the rostral ventromedial medulla (RVM) project to the spinal cord and are involved in descending modulation of pain. Several studies have shown that activation of neurokinin-1 (NK-1) receptors in the RVM produces hyperalgesia, although the underlying mechanisms are not clear. In parallel studies, we compared behavioral measures of hyperalgesia to electrophysiological responses of nociceptive dorsal horn neurons produced by activation of NK-1 receptors in the RVM. Injection of the selective NK-1 receptor agonist Sar9,Met(O2)11-substance P (SSP) into the RVM produced dose-dependent mechanical and heat hyperalgesia that was blocked by coadministration of the selective NK-1 receptor antagonist L-733,060. In electrophysiological studies, responses evoked by mechanical and heat stimuli were obtained from identified high-threshold (HT) and wide dynamic range (WDR) neurons. Injection of SSP into the RVM enhanced responses of WDR neurons, including identified neurons that project to the parabrachial area, to mechanical and heat stimuli. Since intraplantar injection of capsaicin produces robust hyperalgesia and sensitization of nociceptive spinal neurons, we examined whether this sensitization was dependent on NK-1 receptors in the RVM. Pretreatment with L-733,060 into the RVM blocked the sensitization of dorsal horn neurons produced by capsaicin. c-Fos labeling was used to determine the spatial distribution of dorsal horn neurons that were sensitized by NK-1 receptor activation in the RVM. Consistent with our electrophysiological results, administration of SSP into the RVM increased pinch-evoked c-Fos expression in the dorsal horn. It is suggested that targeting this descending pathway may be effective in reducing persistent pain.NEW & NOTEWORTHY It is known that activation of neurokinin-1 (NK-1) receptors in the rostral ventromedial medulla (RVM), a main output area for descending modulation of pain, produces hyperalgesia. Here we show that activation of NK-1 receptors produces hyperalgesia by sensitizing nociceptive dorsal horn neurons. Targeting this pathway at its origin or in the spinal cord may be an effective approach for pain management.
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Affiliation(s)
- Sergey G Khasabov
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, Minnesota; and
| | - Patrick Malecha
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, Minnesota; and
| | - Joseph Noack
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, Minnesota; and
| | - Janneta Tabakov
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, Minnesota; and
| | - Glenn J Giesler
- Department of Neuroscience, University of Minnesota, School of Medicine, Minneapolis, Minnesota
| | - Donald A Simone
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, Minnesota; and
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76
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Beckers AB, Weerts ZZRM, Helyes Z, Masclee AAM, Keszthelyi D. Review article: transient receptor potential channels as possible therapeutic targets in irritable bowel syndrome. Aliment Pharmacol Ther 2017; 46:938-952. [PMID: 28884838 DOI: 10.1111/apt.14294] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 06/06/2017] [Accepted: 08/17/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND Abdominal pain in irritable bowel syndrome (IBS) remains challenging to treat effectively. Researchers have attempted to elucidate visceral nociceptive processes in order to guide treatment development. Transient receptor potential (TRP) channels have been implied in the generation (TRPV1, TRPV4, TRPA1) and inhibition (TRPM8) of visceral pain signals. Pathological changes in their functioning have been demonstrated in inflammatory conditions, and appear to be present in IBS as well. AIM To provide a comprehensive review of the current literature on TRP channels involved in visceral nociception. In particular, we emphasise the clinical implications of these nociceptors in the treatment of IBS. METHODS Evidence to support this review was obtained from an electronic database search via PubMed using the search terms "visceral nociception," "visceral hypersensitivity," "irritable bowel syndrome" and "transient receptor potential channels." After screening the abstracts the articles deemed relevant were cross-referenced for additional manuscripts. RESULTS Recent studies have resulted in significant advances in our understanding of TRP channel mediated visceral nociception. The diversity of TRP channel sensitization pathways is increasingly recognised. Endogenous TRP agonists, including poly-unsaturated fatty acid metabolites and hydrogen sulphide, have been implied in augmented visceral pain generation in IBS. New potential targets for treatment development have been identified (TRPA1 and TRPV4,) and alternative means of affecting TRP channel signalling (partial antagonists, downstream targeting and RNA-based therapy) are currently being explored. CONCLUSIONS The improved understanding of mechanisms involved in visceral nociception provides a solid basis for the development of new treatment strategies for abdominal pain in IBS.
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Affiliation(s)
- A B Beckers
- Division of Gastroenterology-Hepatology, Department of Internal Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, Limburg, The Netherlands
| | - Z Z R M Weerts
- Division of Gastroenterology-Hepatology, Department of Internal Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, Limburg, The Netherlands
| | - Z Helyes
- Department of Pharmacology and Pharmacotherapy, Molecular Pharmacology Research Team, University of Pécs Medical School, János Szentágothai Research Centre, University of Pécs, Pécs, Baranya, Hungary
| | - A A M Masclee
- Division of Gastroenterology-Hepatology, Department of Internal Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, Limburg, The Netherlands
| | - D Keszthelyi
- Division of Gastroenterology-Hepatology, Department of Internal Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, Limburg, The Netherlands
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77
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A nociceptive stress model of adolescent physical abuse induces contextual fear and cingulate nociceptive neuroplasticities. Brain Struct Funct 2017; 223:429-448. [PMID: 28861709 DOI: 10.1007/s00429-017-1502-3] [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: 08/18/2016] [Accepted: 08/18/2017] [Indexed: 10/19/2022]
Abstract
Adolescent physical abuse impairs emotional development and evokes cingulate pathologies, but its neuronal and circuit substrates are unknown. Conditioning adolescent rabbits with noxious colorectal distension for only 2 h over 3 weeks simulated the human child abuse in amplitude, frequency, and duration. Thermal withdrawal thresholds were unchanged suggesting that sensitized spinal mechanisms may not be operable. Unchanged weight, stools, colorectal histology, and no evidence of abdominal pain argue against tissue injury or irritable bowel syndrome. Contextual fear was amplified as they avoided the site of their abuse. Conditioning impacted anterior cingulate and anterior midcingulate (ACC, aMCC) neuron excitability: (1) more neurons responded to cutaneous and visceral (VNox) noxious stimuli than controls engaging latent nociception (present but not manifest in controls). (2) Rear paw stimulation increased responses over forepaws with shorter onsets and longer durations, while forepaw responses were of higher amplitude. (3) There were more VNox responses with two excitatory phases and longer durations. (4) Some had unique three-phase excitatory responses. (5) Long-duration VNox stimuli did not inhibit neurons as in controls, suggesting the release of an inhibitory circuit. (6) aMCC changes in cutaneous but not visceral nociception confirmed its role in cutaneous nociception. For the first time, we report neuroplasticities that may be evoked by adolescent physical abuse and reflect psychogenic pain: i.e., no ongoing peripheral pain and altered ACC nociception. These limbic responses may be a cognitive trace of abuse and may shed light on impaired human emotional development and sexual function.
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78
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Carletti R, Tacconi S, Mugnaini M, Gerrard P. Receptor distribution studies. Curr Opin Pharmacol 2017; 35:94-100. [PMID: 28803835 DOI: 10.1016/j.coph.2017.07.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 07/23/2017] [Indexed: 12/18/2022]
Abstract
Receptor distribution studies have played a key role in the characterization of receptor systems (e.g. GABAB, NMDA (GluNRs), and Neurokinin 1) and in generating hypotheses to exploit these systems as potential therapeutic targets. Distribution studies can provide important information on the potential role of candidate receptors in normal physiology/disease and alert for possible adverse effects of targeting the receptors. Moreover, they can provide valuable information relating to quantitative target engagement (e.g. % receptor occupancy) to drive mechanistic pharmacokinetic/pharmacodynamic (PK/PD) hypotheses for compounds in the Drug Discovery process. Finally, receptor distribution and quantitative target engagement studies can be used to validate truly translational technologies such as PET ligands and pharmacoEEG paradigms to facilitate bridging of the preclinical/clinical interface and thus increase probability of success.
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Affiliation(s)
- Renzo Carletti
- Center of Drug Discovery & Development, Aptuit S.r.l., via Fleming 4, 37135 Verona, Italy.
| | - Stefano Tacconi
- Center of Drug Discovery & Development, Aptuit S.r.l., via Fleming 4, 37135 Verona, Italy
| | - Manolo Mugnaini
- Neuroscience Discovery, AbbVie Deutschland GmbH & Co. KG, Knollstraße 50, 67061 Ludwigshafen, Germany
| | - Philip Gerrard
- Center of Drug Discovery & Development, Aptuit S.r.l., via Fleming 4, 37135 Verona, Italy
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79
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Abstract
Acute and chronic pain complaints, although common, are generally poorly served by existing therapies. This unmet clinical need reflects a failure to develop novel classes of analgesics with superior efficacy, diminished adverse effects and a lower abuse liability than those currently available. Reasons for this include the heterogeneity of clinical pain conditions, the complexity and diversity of underlying pathophysiological mechanisms, and the unreliability of some preclinical pain models. However, recent advances in our understanding of the neurobiology of pain are beginning to offer opportunities for developing novel therapeutic strategies and revisiting existing targets, including modulating ion channels, enzymes and G-protein-coupled receptors.
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80
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Ängeby Möller K, Svärd H, Suominen A, Immonen J, Holappa J, Stenfors C. Gait analysis and weight bearing in pre-clinical joint pain research. J Neurosci Methods 2017; 300:92-102. [PMID: 28445709 DOI: 10.1016/j.jneumeth.2017.04.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Revised: 04/19/2017] [Accepted: 04/20/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND There is a need for better joint pain treatment, but development of new medication has not been successful. Pre-clinical models with readouts that better reflect the clinical situation are needed. In patients with joint pain, pain at rest and pain at walking are two major complaints. NEW METHOD We describe a new way of calculating results from gait analysis using the CatWalk™ setup. Rats with monoarthritis induced by injection of Complete Freund's Adjuvant (CFA) intra-articularly into the ankle joint of one hind limb were used to assess gait and dynamic weight bearing. RESULTS The results show that dynamic weight bearing was markedly reduced for the injected paw. Gait parameters such as amount of normal step sequences, walking speed and duration of step placement were also affected. Treatment with naproxen (an NSAID commonly used for inflammatory pain) attenuated the CFA-induced effects. Pregabalin, which is used for neuropathic pain, had no effect. COMPARISON WITH EXISTING METHODS Reduced dynamic weight bearing during locomotion, assessed and calculated in the way we present here, showed a dose-dependent and lasting normalization after naproxen treatment. In contrast, static weight bearing while standing (Incapacitance tester) showed a significant effect for a limited time only. Mechanical sensitivity (von Frey Optihairs) was completely normalized by naproxen, and the window for testing pharmacological effect disappeared. CONCLUSIONS Objective and reproducible effects, with an endpoint showing face validity compared to pain while walking in patients with joint pain, are achieved by a new way of calculating dynamic weight bearing in monoarthritic rats.
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Affiliation(s)
- Kristina Ängeby Möller
- CNS Research, Orion Corporation Orion Pharma, Turku, Finland; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
| | - Heta Svärd
- CNS Research, Orion Corporation Orion Pharma, Turku, Finland
| | - Anni Suominen
- CNS Research, Orion Corporation Orion Pharma, Turku, Finland
| | - Jarmo Immonen
- CNS Research, Orion Corporation Orion Pharma, Turku, Finland
| | - Johanna Holappa
- CNS Research, Orion Corporation Orion Pharma, Turku, Finland
| | - Carina Stenfors
- CNS Research, Orion Corporation Orion Pharma, Turku, Finland
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81
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A role for neurokinin-1 receptor neurons in the rostral ventromedial medulla in the development of chronic postthoracotomy pain. Pain 2017. [DOI: 10.1097/j.pain.0000000000000919] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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82
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Schomberg DT, Miranpuri GS, Chopra A, Patel K, Meudt JJ, Tellez A, Resnick DK, Shanmuganayagam D. Translational Relevance of Swine Models of Spinal Cord Injury. J Neurotrauma 2017; 34:541-551. [DOI: 10.1089/neu.2016.4567] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Dominic T. Schomberg
- Biomedical and Genomic Research Group, Department of Animal Sciences, University of Wisconsin–Madison, Wisconsin
| | - Gurwattan S. Miranpuri
- Department of Neurological Surgery, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Abhishek Chopra
- Department of Neurological Surgery, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Kush Patel
- Department of Neurological Surgery, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Jennifer J. Meudt
- Biomedical and Genomic Research Group, Department of Animal Sciences, University of Wisconsin–Madison, Wisconsin
| | | | - Daniel K. Resnick
- Department of Neurological Surgery, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Dhanansayan Shanmuganayagam
- Biomedical and Genomic Research Group, Department of Animal Sciences, University of Wisconsin–Madison, Wisconsin
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83
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Azimi E, Reddy VB, Shade KTC, Anthony RM, Talbot S, Pereira PJS, Lerner EA. Dual action of neurokinin-1 antagonists on Mas-related GPCRs. JCI Insight 2016; 1:e89362. [PMID: 27734033 DOI: 10.1172/jci.insight.89362] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The challenge of translating findings from animal models to the clinic is well known. An example of this challenge is the striking effectiveness of neurokinin-1 receptor (NK-1R) antagonists in mouse models of inflammation coupled with their equally striking failure in clinical investigations in humans. Here, we provide an explanation for this dichotomy: Mas-related GPCRs (Mrgprs) mediate some aspects of inflammation that had been considered mediated by NK-1R. In support of this explanation, we show that conventional NK-1R antagonists have off-target activity on the mouse receptor MrgprB2 but not on the homologous human receptor MRGPRX2. An unrelated tripeptide NK-1R antagonist has dual activity on MRGPRX2. This tripeptide both suppresses itch in mice and inhibits degranulation from the LAD-2 human mast cell line elicited by basic secretagogue activation of MRGPRX2. Antagonists of Mrgprs may fill the void left by the failure of NK-1R antagonists.
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Affiliation(s)
- Ehsan Azimi
- Cutaneous Biology Research Center, Department of Dermatology, and
| | - Vemuri B Reddy
- Cutaneous Biology Research Center, Department of Dermatology, and
| | - Kai-Ting C Shade
- Center for Immunology and Inflammatory Diseases, Division of Rheumatology, Allergy, and Immunology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Robert M Anthony
- Center for Immunology and Inflammatory Diseases, Division of Rheumatology, Allergy, and Immunology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Sebastien Talbot
- FM Kirby Neurobiology Center, Children's Hospital Boston, Boston, Massachusetts, USA
| | - Paula Juliana Seadi Pereira
- Cutaneous Biology Research Center, Department of Dermatology, and.,Programa de Pós-graduação em Biologia Celular e Molecular, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Ethan A Lerner
- Cutaneous Biology Research Center, Department of Dermatology, and
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84
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Comparison of the Prophylactic Antiemetic Efficacy of Aprepitant Plus Palonosetron Versus Aprepitant Plus Ramosetron in Patients at High Risk for Postoperative Nausea and Vomiting After Laparoscopic Cholecystectomy: A Prospective Randomized-controlled Trial. Surg Laparosc Endosc Percutan Tech 2016; 26:354-357. [DOI: 10.1097/sle.0000000000000316] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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85
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Decreased Brain Neurokinin-1 Receptor Availability in Chronic Tennis Elbow. PLoS One 2016; 11:e0161563. [PMID: 27658244 PMCID: PMC5033598 DOI: 10.1371/journal.pone.0161563] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 08/08/2016] [Indexed: 12/28/2022] Open
Abstract
Substance P is released in painful and inflammatory conditions, affecting both peripheral processes and the central nervous system neurokinin 1 (NK1) receptor. There is a paucity of data on human brain alterations in NK1 expression, how this system may be affected by treatment, and interactions between central and peripheral tissue alterations. Ten subjects with chronic tennis elbow (lateral epicondylosis) were selected out of a larger (n = 120) randomized controlled trial evaluating graded exercise as a treatment for chronic tennis elbow (lateral epicondylosis). These ten subjects were examined by positron emission tomography (PET) with the NK1-specific radioligand 11C-GR205171 before, and eight patients were followed up after treatment with graded exercise. Brain binding in the ten patients before treatment, reflecting NK1-receptor availability (NK1-RA), was compared to that of 18 healthy subjects and, longitudinally, to the eight of the original ten patients that agreed to a second PET examination after treatment. Before treatment, patients had significantly lower NK1-RA in the insula, vmPFC, postcentral gyrus, anterior cingulate, caudate, putamen, amygdala and the midbrain but not the thalamus and cerebellum, with the largest difference in the insula contralateral to the injured elbow. No significant correlations between brain NK1-RA and pain, functional severity, or peripheral NK1-RA in the affected limb were observed. In the eight patients examined after treatment, pain ratings decreased in everyone, but there were no significant changes in NK1-RA. These findings indicate a role for the substance P (SP) / NK1 receptor system in musculoskeletal pain and tissue healing. As neither clinical parameters nor successful treatment response was reflected in brain NK1-RA after treatment, this may reflect the diverse function of the SP/NK1 system in CNS and peripheral tissue, or a change too small or slow to capture over the three-month treatment.
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86
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Valtcheva MV, Copits BA, Davidson S, Sheahan TD, Pullen MY, McCall JG, Dikranian K, Gereau RW. Surgical extraction of human dorsal root ganglia from organ donors and preparation of primary sensory neuron cultures. Nat Protoc 2016; 11:1877-88. [PMID: 27606776 PMCID: PMC5082842 DOI: 10.1038/nprot.2016.111] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Primary cultures of rodent sensory neurons are widely used to investigate the cellular and molecular mechanisms involved in pain, itch, nerve injury and regeneration. However, translation of these preclinical findings may be greatly improved by direct validation in human tissues. We have developed an approach to extract and culture human sensory neurons in collaboration with a local organ procurement organization (OPO). Here we describe the surgical procedure for extraction of human dorsal root ganglia (hDRG) and the necessary modifications to existing culture techniques to prepare viable adult human sensory neurons for functional studies. Dissociated sensory neurons can be maintained in culture for >10 d, and they are amenable to electrophysiological recording, calcium imaging and viral gene transfer. The entire process of extraction and culturing can be completed in <7 h, and it can be performed by trained graduate students. This approach can be applied at any institution with access to organ donors consenting to tissue donation for research, and is an invaluable resource for improving translational research.
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Affiliation(s)
- Manouela V Valtcheva
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA.,Medical Scientist Training Program, Washington University in St. Louis, St. Louis, Missouri, USA.,Neurosciences Program, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Bryan A Copits
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Steve Davidson
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA.,Pain Research Center, Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Tayler D Sheahan
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA.,Neurosciences Program, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Melanie Y Pullen
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA.,Developmental, Regenerative, and Stem Cell Biology Program, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Jordan G McCall
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Krikor Dikranian
- Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Robert W Gereau
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA
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87
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Ormandy EH, Griffin G. Attitudes toward the use of Animals in Chronic versus Acute Pain Research: Results of a Web-based Forum. Altern Lab Anim 2016; 44:323-335. [DOI: 10.1177/026119291604400410] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
When asked about the use of animals in biomedical research, people often state that the research is only acceptable if pain and distress are minimised. However, pain is caused when the aim is to study pain itself, resulting in unalleviated pain for many of the animals involved. Consequently, the use of animals in pain research is often considered contentious. To date, no research has explored people's views toward different types of animal-based pain research (e.g. chronic or acute pain). This study used a web-based survey to explore people's willingness to support the use of mice in chronic versus acute pain research. The majority of the participants opposed the use of mice for either chronic (68.3%) or acute (63.1%) pain research. There was no difference in the levels of support or opposition for chronic versus acute pain research. Unsupportive participants justified their opposition by focusing on the perceived lack of scientific merit, or the existence of non-animal alternatives. Supporters emphasised the potential benefits that could arise, with some stating that the benefits outweigh the costs. The majority of the participants were opposed to pain research involving mice, regardless of the nature and duration of the pain inflicted, or the perceived benefit of the research. A better understanding of public views toward animal use in pain research may provide a stronger foundation for the development of policy governing the use of animals in research where animals are likely to experience unalleviated pain.
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Affiliation(s)
- Elisabeth H. Ormandy
- The University of British Columbia, Animal Welfare Program, Vancouver, British Columbia, Canada
| | - Gilly Griffin
- Canadian Council on Animal Care, Ottawa, Ontario, Canada
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88
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Huang D, Huang S, Gao H, Liu Y, Qi J, Chen P, Wang C, Scragg JL, Vakurov A, Peers C, Du X, Zhang H, Gamper N. Redox-Dependent Modulation of T-Type Ca(2+) Channels in Sensory Neurons Contributes to Acute Anti-Nociceptive Effect of Substance P. Antioxid Redox Signal 2016; 25:233-51. [PMID: 27306612 PMCID: PMC4971421 DOI: 10.1089/ars.2015.6560] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 05/26/2016] [Accepted: 06/14/2016] [Indexed: 02/05/2023]
Abstract
AIMS Neuropeptide substance P (SP) is produced and released by a subset of peripheral sensory neurons that respond to tissue damage (nociceptors). SP exerts excitatory effects in the central nervous system, but peripheral SP actions are still poorly understood; therefore, here, we aimed at investigating these peripheral mechanisms. RESULTS SP acutely inhibited T-type voltage-gated Ca(2+) channels in nociceptors. The effect was mediated by neurokinin 1 (NK1) receptor-induced stimulation of intracellular release of reactive oxygen species (ROS), as it can be prevented or reversed by the reducing agent dithiothreitol and mimicked by exogenous or endogenous ROS. This redox-mediated T-type Ca(2+) channel inhibition operated through the modulation of CaV3.2 channel sensitivity to ambient zinc, as it can be prevented or reversed by zinc chelation and mimicked by exogenous zinc. Elimination of the zinc-binding site in CaV3.2 rendered the channel insensitive to SP-mediated inhibition. Importantly, peripherally applied SP significantly reduced bradykinin-induced nociception in rats in vivo; knock-down of CaV3.2 significantly reduced this anti-nociceptive effect. This atypical signaling cascade shared the initial steps with the SP-mediated augmentation of M-type K(+) channels described earlier. INNOVATION Our study established a mechanism underlying the peripheral anti-nociceptive effect of SP whereby this neuropeptide produces ROS-dependent inhibition of pro-algesic T-type Ca(2+) current and concurrent enhancement of anti-algesic M-type K(+) current. These findings will lead to a better understanding of mechanisms of endogenous analgesia. CONCLUSION SP modulates T-type channel activity in nociceptors by a redox-dependent tuning of channel sensitivity to zinc; this novel modulatory pathway contributes to the peripheral anti-nociceptive effect of SP. Antioxid. Redox Signal. 25, 233-251.
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Affiliation(s)
- Dongyang Huang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, P.R. China
| | - Sha Huang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, P.R. China
| | - Haixia Gao
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, P.R. China
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Yani Liu
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, P.R. China
| | - Jinlong Qi
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, P.R. China
| | - Pingping Chen
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, P.R. China
| | - Caixue Wang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, P.R. China
| | - Jason L. Scragg
- Leeds Institute of Cardiovascular and Metabolic Medicine (LICAMM), Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom
| | - Alexander Vakurov
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Chris Peers
- Leeds Institute of Cardiovascular and Metabolic Medicine (LICAMM), Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom
| | - Xiaona Du
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, P.R. China
| | - Hailin Zhang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, P.R. China
| | - Nikita Gamper
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, P.R. China
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
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Burma NE, Leduc-Pessah H, Fan CY, Trang T. Animal models of chronic pain: Advances and challenges for clinical translation. J Neurosci Res 2016; 95:1242-1256. [PMID: 27376591 DOI: 10.1002/jnr.23768] [Citation(s) in RCA: 119] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/25/2016] [Accepted: 04/29/2016] [Indexed: 12/17/2022]
Abstract
Chronic pain is a global problem that has reached epidemic proportions. An estimated 20% of adults suffer from pain, and another 10% are diagnosed with chronic pain each year (Goldberg and McGee, ). Despite the high prevalence of chronic pain (an estimated 1.5 billion people are afflicted worldwide), much remains to be understood about the underlying causes of this condition, and there is an urgent requirement for better pain therapies. The discovery of novel targets and the development of better analgesics rely on an assortment of preclinical animal models; however, there are major challenges to translating discoveries made in animal models to realized pain therapies in humans. This review discusses common animal models used to recapitulate clinical chronic pain conditions (such as neuropathic, inflammatory, and visceral pain) and the methods for assessing the sensory and affective components of pain in animals. We also discuss the advantages and limitations of modeling chronic pain in animals as well as highlighting strategies for improving the predictive validity of preclinical pain studies. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Nicole E Burma
- Departments of Comparative Biology and Experimental Medicine, and Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Heather Leduc-Pessah
- Departments of Comparative Biology and Experimental Medicine, and Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Churmy Y Fan
- Departments of Comparative Biology and Experimental Medicine, and Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Tuan Trang
- Departments of Comparative Biology and Experimental Medicine, and Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
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Tabakoff B, Ren W, Vanderlinden L, Snell LD, Matheson CJ, Wang ZJ, Levinson R, Smothers CT, Woodward JJ, Honse Y, Lovinger D, Rush AM, Sather WA, Gustafson DL, Hoffman PL. A novel substituted aminoquinoline selectively targets voltage-sensitive sodium channel isoforms and NMDA receptor subtypes and alleviates chronic inflammatory and neuropathic pain. Eur J Pharmacol 2016; 784:1-14. [PMID: 27158117 DOI: 10.1016/j.ejphar.2016.05.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 05/03/2016] [Accepted: 05/04/2016] [Indexed: 12/19/2022]
Abstract
Recent understanding of the systems that mediate complex disease states, has generated a search for molecules that simultaneously modulate more than one component of a pathologic pathway. Chronic pain syndromes are etiologically connected to functional changes (sensitization) in both peripheral sensory neurons and in the central nervous system (CNS). These functional changes involve modifications of a significant number of components of signal generating, signal transducing and signal propagating pathways. Our analysis of disease-related changes which take place in sensory neurons during sensitization led to the design of a molecule that would simultaneously inhibit peripheral NMDA receptors and voltage sensitive sodium channels. In the current report, we detail the selectivity of N,N-(diphenyl)-4-ureido-5,7-dichloro-2-carboxy-quinoline (DCUKA) for action at NMDA receptors composed of different subunit combinations and voltage sensitive sodium channels having different α subunits. We show that DCUKA is restricted to the periphery after oral administration, and that circulating blood levels are compatible with its necessary concentrations for effects at the peripheral cognate receptors/channels that were assayed in vitro. Our results demonstrate that DCUKA, at concentrations circulating in the blood after oral administration, can modulate systems which are upregulated during peripheral sensitization, and are important for generating and conducting pain information to the CNS. Furthermore, we demonstrate that DCUKA ameliorates the hyperalgesia of chronic pain without affecting normal pain responses in neuropathic and inflammation-induced chronic pain models.
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Affiliation(s)
- Boris Tabakoff
- Lohocla Research Corporation, Colorado Bioscience Building, 12635 East Montview Blvd., Suite 128, Aurora, CO 80045, USA; Department of Pharmaceutical Sciences, Skaggs School of Pharmacy & Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Campus Box: C238 12850, E. Montview Blvd., Aurora, CO 80045, USA.
| | - Wenhua Ren
- Lohocla Research Corporation, Colorado Bioscience Building, 12635 East Montview Blvd., Suite 128, Aurora, CO 80045, USA.
| | - Lauren Vanderlinden
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy & Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Campus Box: C238 12850, E. Montview Blvd., Aurora, CO 80045, USA.
| | - Lawrence D Snell
- Lohocla Research Corporation, Colorado Bioscience Building, 12635 East Montview Blvd., Suite 128, Aurora, CO 80045, USA.
| | - Christopher J Matheson
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy & Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Campus Box: C238 12850, E. Montview Blvd., Aurora, CO 80045, USA.
| | - Ze-Jun Wang
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, 12800 E. 19 Ave., Aurora, CO 80045 USA.
| | - Rock Levinson
- Department of Physiology & Biophysics, University of Colorado Anschutz Medical Campus, 12800 E. 19th Ave., Aurora, CO 80045, USA.
| | - C Thetford Smothers
- Department of Neurosciences and Department of Psychiatry, Medical University of South Carolina, 171 Ashley Ave., Charleston, SC 29425, USA.
| | - John J Woodward
- Department of Neurosciences and Department of Psychiatry, Medical University of South Carolina, 171 Ashley Ave., Charleston, SC 29425, USA.
| | - Yumiko Honse
- Clinical and Biological Research Unit, NIAAA, 12420 Parklawn Dr., MSC 8115, Bethesda, MD 20892-8115, USA.
| | - David Lovinger
- Clinical and Biological Research Unit, NIAAA, 12420 Parklawn Dr., MSC 8115, Bethesda, MD 20892-8115, USA.
| | | | - William A Sather
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, 12800 E. 19 Ave., Aurora, CO 80045 USA.
| | - Daniel L Gustafson
- UCCC Pharmacology Shared Resource, Colorado State University, Veterinary Teaching Hospital, A CC246, 300 West Drake Road, Fort Collins, CO 80023, USA.
| | - Paula L Hoffman
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, 12800 E. 19 Ave., Aurora, CO 80045 USA.
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Newberry K, Wang S, Hoque N, Kiss L, Ahlijanian MK, Herrington J, Graef JD. Development of a spontaneously active dorsal root ganglia assay using multiwell multielectrode arrays. J Neurophysiol 2016; 115:3217-28. [PMID: 27052585 DOI: 10.1152/jn.01122.2015] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 04/05/2016] [Indexed: 11/22/2022] Open
Abstract
In vitro phenotypic assays of sensory neuron activity are important tools for identifying potential analgesic compounds. These assays are typically characterized by hyperexcitable and/or abnormally, spontaneously active cells. Whereas manual electrophysiology experiments provide high-resolution biophysical data to characterize both in vitro models and potential therapeutic modalities (e.g., action potential characteristics, the role of specific ion channels, and receptors), these techniques are hampered by their low throughput. We have established a spontaneously active dorsal root ganglia (DRG) platform using multiwell multielectrode arrays (MEAs) that greatly increase the ability to evaluate the effects of multiple compounds and conditions on DRG excitability within the context of a cellular network. We show that spontaneous DRG firing can be attenuated with selective Na(+) and Ca(2+) channel blockers, as well as enhanced with K(+) channel blockers. In addition, spontaneous activity can be augmented with both the transient receptor potential cation channel subfamily V member 1 agonist capsaicin and the peptide bradykinin and completely blocked with neurokinin receptor antagonists. Finally, we validated the use of this assay by demonstrating that commonly used neuropathic pain therapeutics suppress DRG spontaneous activity. Overall, we have optimized primary rat DRG cells on a multiwell MEA platform to generate and characterize spontaneously active cultures that have the potential to be used as an in vitro phenotypic assay to evaluate potential therapeutics in rodent models of pain.
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Affiliation(s)
- Kim Newberry
- Genetically Defined Diseases, Bristol-Myers Squibb Company, Wallingford, Connecticut; and
| | - Shuya Wang
- Genetically Defined Diseases, Bristol-Myers Squibb Company, Wallingford, Connecticut; and
| | - Nina Hoque
- Genetically Defined Diseases, Bristol-Myers Squibb Company, Wallingford, Connecticut; and
| | - Laszlo Kiss
- Leads Discovery and Optimization, Bristol-Myers Squibb Company, Wallingford, Connecticut
| | - Michael K Ahlijanian
- Genetically Defined Diseases, Bristol-Myers Squibb Company, Wallingford, Connecticut; and
| | - James Herrington
- Genetically Defined Diseases, Bristol-Myers Squibb Company, Wallingford, Connecticut; and
| | - John D Graef
- Genetically Defined Diseases, Bristol-Myers Squibb Company, Wallingford, Connecticut; and
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93
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Harte SE, Meyers JB, Donahue RR, Taylor BK, Morrow TJ. Mechanical Conflict System: A Novel Operant Method for the Assessment of Nociceptive Behavior. PLoS One 2016; 11:e0150164. [PMID: 26915030 PMCID: PMC4767889 DOI: 10.1371/journal.pone.0150164] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 02/10/2016] [Indexed: 11/19/2022] Open
Abstract
A new operant test for preclinical pain research, termed the Mechanical Conflict System (MCS), is presented. Rats were given a choice either to remain in a brightly lit compartment or to escape to a dark compartment by crossing an array of height-adjustable nociceptive probes. Latency to escape the light compartment was evaluated with varying probe heights (0, .5, 1, 2, 3, and 4 mm above compartment floor) in rats with neuropathic pain induced by constriction nerve injury (CCI) and in naive control rats. Escape responses in CCI rats were assessed following intraperitoneal administration of pregabalin (10 and 30 mg/kg), morphine (2.5 and 5 mg/kg), and the tachykinin NK1 receptor antagonist, RP 67580 (1 and 10 mg/kg). Results indicate that escape latency increased as a function of probe height in both naive and CCI rats. Pregabalin (10 and 30 mg/kg) and morphine (5 mg/kg), but not RP 67580, decreased latency to escape in CCI rats suggesting an antinociceptive effect. In contrast, morphine (10 mg/kg) but not pregabalin (30 mg/kg) increased escape latency in naive rats suggesting a possible anxiolytic action of morphine in response to light-induced fear. No order effects following multiple test sessions were observed. We conclude that the MCS is a valid method to assess behavioral signs of affective pain in rodents.
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Affiliation(s)
- Steven E. Harte
- Department of Anesthesiology, Chronic Pain and Fatigue Research Center, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Internal Medicine, Division of Rheumatology, University of Michigan, Ann Arbor, Michigan, United States of America
- Neurology Service, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan, United States of America
- * E-mail:
| | - Jessica B. Meyers
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
- Neurology Service, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan, United States of America
| | - Renee R. Donahue
- Department of Physiology, University of Kentucky, Lexington, Kentucky, United States of America
| | - Bradley K. Taylor
- Department of Physiology, University of Kentucky, Lexington, Kentucky, United States of America
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, Kentucky, United States of America
| | - Thomas J. Morrow
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
- Neurology Service, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan, United States of America
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94
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Whiteside GT, Pomonis JD, Kennedy JD. Preclinical Pharmacological Approaches in Drug Discovery for Chronic Pain. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2016; 75:303-23. [PMID: 26920017 DOI: 10.1016/bs.apha.2015.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In recent years, animal behavioral models, particularly those used in pain research, have been increasingly scrutinized and criticized for their role in the poor translation of novel pharmacotherapies for chronic pain. This chapter addresses the use of animal models of pain used in drug discovery research. It highlights how, when, and why animal models of pain are used as one of the many experimental tools used to gain better understanding of target mechanisms and rank-order compounds in the iterative process of establishing structure-activity relationship. Together, these models help create an "analgesic signature" for a compound and inform the indications most likely to yield success in clinical trials. In addition, the authors discuss some often underappreciated aspects of currently used (traditional) animal models of pain, including simply applying basic pharmacological principles to study design and data interpretation as well as consideration of efficacy alongside side effect measures as part of the overall conclusion of efficacy. This is provided to add perspective regarding current efforts to develop new models and endpoints both in rodents and in larger animal species as well as assess cognitive and/or affective aspects of pain. Finally, the authors suggest ways in which efficacy evaluation in animal models of pain, whether traditional or new, might better align with clinical standards of analysis, citing examples where applying effect size and number needed to treat estimations to animal model data suggest that the efficacy bar often may be set too low preclinically to allow successful translation to the clinical setting.
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Affiliation(s)
| | - James D Pomonis
- American Preclinical Services, LLC, Minneapolis, Minnesota, USA
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95
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Castel D, Sabbag I, Brenner O, Meilin S. Peripheral Neuritis Trauma in Pigs: A Neuropathic Pain Model. THE JOURNAL OF PAIN 2016; 17:36-49. [DOI: 10.1016/j.jpain.2015.09.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 09/21/2015] [Accepted: 09/26/2015] [Indexed: 12/29/2022]
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Wanigasekera V, Mezue M, Andersson J, Kong Y, Tracey I. Disambiguating Pharmacodynamic Efficacy from Behavior with Neuroimaging: Implications for Analgesic Drug Development. Anesthesiology 2016; 124:159-68. [PMID: 26669989 PMCID: PMC4684093 DOI: 10.1097/aln.0000000000000924] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Attrition rates of new analgesics during drug development are high; poor assay sensitivity with reliance on subjective outcome measures being a crucial factor. METHODS The authors assessed the utility of functional magnetic resonance imaging with capsaicin-induced central sensitization, a mechanism relevant in neuropathic pain, for obtaining mechanism-based objective outcome measures that can differentiate an effective analgesic (gabapentin) from an ineffective analgesic (ibuprofen) and both from placebo. The authors used a double-blind, randomized phase I study design (N = 24) with single oral doses. RESULTS Only gabapentin suppressed the secondary mechanical hyperalgesia-evoked neural response in a region of the brainstem's descending pain modulatory system (right nucleus cuneiformis) and left (contralateral) posterior insular cortex and secondary somatosensory cortex. Similarly, only gabapentin suppressed the resting-state functional connectivity during central sensitization between the thalamus and secondary somatosensory cortex, which was plasma gabapentin level dependent. A power analysis showed that with 12 data sets, when using neural activity from the left posterior insula and right nucleus cuneiformis, a statistically significant difference between placebo and gabapentin was detected with probability ≥ 0.8. When using subjective pain ratings, this reduced to less than or equal to 0.6. CONCLUSIONS Functional imaging with central sensitization can be used as a sensitive mechanism-based assay to guide go/no-go decisions on selecting analgesics effective in neuropathic pain in early human drug development. We also show analgesic modulation of neural activity by using resting-state functional connectivity, a less challenging paradigm that is ideally suited for patient studies because it requires no task or pain provocation.
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Affiliation(s)
- Vishvarani Wanigasekera
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB) & Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurosciences University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, United Kingdom. Telephone +441865 222736
| | - Melvin Mezue
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB) & Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurosciences University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, United Kingdom. Telephone +441865 222736
| | - Jesper Andersson
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB) & Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurosciences University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, United Kingdom. Telephone +441865 222736
| | - Yazhuo Kong
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB) & Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurosciences University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, United Kingdom. Telephone +441865 222736
| | - Irene Tracey
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB) & Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurosciences University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, United Kingdom. Telephone +441865 222736
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Sisignano M, Parnham MJ, Geisslinger G. Drug Repurposing for the Development of Novel Analgesics. Trends Pharmacol Sci 2015; 37:172-183. [PMID: 26706620 DOI: 10.1016/j.tips.2015.11.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 11/16/2015] [Accepted: 11/17/2015] [Indexed: 01/12/2023]
Abstract
Drug development consumes huge amounts of time and money and the search for novel analgesics, which are urgently required, is particularly difficult, having resulted in many setbacks in the past. Drug repurposing - the identification of new uses for existing drugs - is an alternative approach, which bypasses most of the time- and cost-consuming components of drug development. Recent, unexpected findings suggest a role for several existing drugs, such as minocycline, ceftriaxone, sivelestat, and pioglitazone, as novel analgesics in chronic and neuropathic pain states. Here, we discuss these findings as well as their proposed antihyperalgesic mechanisms and outline the merits of pathway-based repurposing screens, in combination with bioinformatics and novel cellular reprogramming techniques, for the identification of novel analgesics.
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Affiliation(s)
- Marco Sisignano
- Institute of Clinical Pharmacology, pharmazentrum Frankfurt/ZAFES, University Hospital of Goethe-University, 60590 Frankfurt am Main, Germany
| | - Michael J Parnham
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Project Group Translational Medicine and Pharmacology (TMP), Theodor-Stern-Kai 7, 60596 Frankfurt am Main, Germany
| | - Gerd Geisslinger
- Institute of Clinical Pharmacology, pharmazentrum Frankfurt/ZAFES, University Hospital of Goethe-University, 60590 Frankfurt am Main, Germany; Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Project Group Translational Medicine and Pharmacology (TMP), Theodor-Stern-Kai 7, 60596 Frankfurt am Main, Germany.
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98
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Muley MM, Krustev E, McDougall JJ. Preclinical Assessment of Inflammatory Pain. CNS Neurosci Ther 2015; 22:88-101. [PMID: 26663896 DOI: 10.1111/cns.12486] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 10/28/2015] [Accepted: 10/29/2015] [Indexed: 12/21/2022] Open
Abstract
While acute inflammation is a natural physiological response to tissue injury or infection, chronic inflammation is maladaptive and engenders a considerable amount of adverse pain. The chemical mediators responsible for tissue inflammation act on nociceptive nerve endings to lower neuronal excitation threshold and sensitize afferent firing rate leading to the development of allodynia and hyperalgesia, respectively. Animal models have aided in our understanding of the pathophysiological mechanisms responsible for the generation of chronic inflammatory pain and allowed us to identify and validate numerous analgesic drug candidates. Here we review some of the commonly used models of skin, joint, and gut inflammatory pain along with their relative benefits and limitations. In addition, we describe and discuss several behavioral and electrophysiological approaches used to assess the inflammatory pain in these preclinical models. Despite significant advances having been made in this area, a gap still exists between fundamental research and the implementation of these findings into a clinical setting. As such we need to characterize inherent pathophysiological pathways and develop new endpoints in these animal models to improve their predictive value of human inflammatory diseases in order to design safer and more effective analgesics.
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Affiliation(s)
- Milind M Muley
- Departments of Pharmacology and Anaesthesia, Pain Management & Perioperative Medicine, Dalhousie University, Halifax, NS, Canada
| | - Eugene Krustev
- Departments of Pharmacology and Anaesthesia, Pain Management & Perioperative Medicine, Dalhousie University, Halifax, NS, Canada
| | - Jason J McDougall
- Departments of Pharmacology and Anaesthesia, Pain Management & Perioperative Medicine, Dalhousie University, Halifax, NS, Canada
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Intra-articular (IA) ropivacaine microparticle suspensions reduce pain, inflammation, cytokine, and substance p levels significantly more than oral or IA celecoxib in a rat model of arthritis. Inflammation 2015; 38:40-60. [PMID: 25189465 DOI: 10.1007/s10753-014-0006-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Current therapeutic treatment options for osteoarthritis entail significant safety concerns. A novel ropivacaine crystalline microsuspension for bolus intra-articular (IA) delivery was thus developed and studied in a peptidoglycan polysaccharide (PGPS)-induced ankle swelling rat model. Compared with celecoxib controls, both oral and IA, ropivacaine IA treatment resulted in a significant reduction of pain upon successive PGPS reactivation, as demonstrated in two different pain models, gait analysis and incapacitance testing. The reduction in pain was attended by a significant reduction in histological inflammation, which in turn was accompanied by significant reductions in the cytokines IL-18 and IL-1β. This may have been due to inhibition of substance P, which was also significantly reduced. Pharmacokinetic analysis indicated that the analgesic effects outlasted measurable ropivacaine levels in either blood or tissue. The results are discussed in the context of pharmacologic mechanisms both of local anesthetics as well as inflammatory arthritis.
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Marquez M, Boscan P, Weir H, Vogel P, Twedt DC. Comparison of NK-1 Receptor Antagonist (Maropitant) to Morphine as a Pre-Anaesthetic Agent for Canine Ovariohysterectomy. PLoS One 2015; 10:e0140734. [PMID: 26513745 PMCID: PMC4626099 DOI: 10.1371/journal.pone.0140734] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 09/28/2015] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE To compare the NK-1 receptor antagonist maropitant to morphine during and after surgery in dogs undergoing ovariohysterectomy (OHE). METHODS 30 healthy female dogs were randomly divided to receive either a pre-anaesthetic dose of morphine (0.5 mg/kg SQ) or maropitant (1 mg/kg, SQ) prior to OHE. Anaesthesia was induced with propofol and maintained with isoflurane. Expired isoflurane concentration, heart rate (HR), systolic arterial pressure (SAP) and respiratory rate were measured. Post-operative pain scores and appetite were evaluated during the recovery period. Rescue analgesia (morphine 0.1 mg/kg IV) was administered as needed post-operatively based on blinded pain score assessments. RESULTS Although clinically comparable; during surgical stimulation, the maropitant group had lower HR (108±18 vs 115±24 bpm; p = 0.04), lower SAP (114±23 vs 125±23 mmHg; p = 0.003) and required slightly lower percent of isoflurane anaesthetic (1.35±0.2 vs 1.51±0.4%; p = 0.005), when compared to the morphine group. In the recovery period, the maropitant group had lower pain scores at extubation (1.7±0.7 vs 3.4±2.3; p = 0.0001) and were more likely to eat within 3 hours after extubation (64.7 vs 15.3%). However, post-operative rescue analgesia requirements were similar between groups. All other measured parameters were similar between groups. The overall difference observed between groups was small and all monitored and measured parameters were within the expected range for anesthetized dogs. CLINICAL SIGNIFICANCE No major differences in cardiorespiratory parameters or anaesthetic requirements were observed between maropitant and morphine when used as a pre-anesthetic agent for OHE. Further studies are necessary to fully elucidate the benefits of maropitant as a pre-anaesthetic agent for canine OHE.
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Affiliation(s)
- Megan Marquez
- Department of Clinical Sciences, Veterinary Teaching Hospital, Colorado State University, Fort Collins, Colorado, United States of America
| | - Pedro Boscan
- Department of Clinical Sciences, Veterinary Teaching Hospital, Colorado State University, Fort Collins, Colorado, United States of America
- * E-mail:
| | - Heather Weir
- Department of Clinical Sciences, Veterinary Teaching Hospital, Colorado State University, Fort Collins, Colorado, United States of America
| | - Pamela Vogel
- Department of Clinical Sciences, Veterinary Teaching Hospital, Colorado State University, Fort Collins, Colorado, United States of America
| | - David C. Twedt
- Department of Clinical Sciences, Veterinary Teaching Hospital, Colorado State University, Fort Collins, Colorado, United States of America
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