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Cao B, Xu Q, Shi Y, Zhao R, Li H, Zheng J, Liu F, Wan Y, Wei B. Pathology of pain and its implications for therapeutic interventions. Signal Transduct Target Ther 2024; 9:155. [PMID: 38851750 PMCID: PMC11162504 DOI: 10.1038/s41392-024-01845-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 04/08/2024] [Accepted: 04/25/2024] [Indexed: 06/10/2024] Open
Abstract
Pain is estimated to affect more than 20% of the global population, imposing incalculable health and economic burdens. Effective pain management is crucial for individuals suffering from pain. However, the current methods for pain assessment and treatment fall short of clinical needs. Benefiting from advances in neuroscience and biotechnology, the neuronal circuits and molecular mechanisms critically involved in pain modulation have been elucidated. These research achievements have incited progress in identifying new diagnostic and therapeutic targets. In this review, we first introduce fundamental knowledge about pain, setting the stage for the subsequent contents. The review next delves into the molecular mechanisms underlying pain disorders, including gene mutation, epigenetic modification, posttranslational modification, inflammasome, signaling pathways and microbiota. To better present a comprehensive view of pain research, two prominent issues, sexual dimorphism and pain comorbidities, are discussed in detail based on current findings. The status quo of pain evaluation and manipulation is summarized. A series of improved and innovative pain management strategies, such as gene therapy, monoclonal antibody, brain-computer interface and microbial intervention, are making strides towards clinical application. We highlight existing limitations and future directions for enhancing the quality of preclinical and clinical research. Efforts to decipher the complexities of pain pathology will be instrumental in translating scientific discoveries into clinical practice, thereby improving pain management from bench to bedside.
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Affiliation(s)
- Bo Cao
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
| | - Qixuan Xu
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
- Medical School of Chinese PLA, Beijing, 100853, China
| | - Yajiao Shi
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China
| | - Ruiyang Zhao
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
- Medical School of Chinese PLA, Beijing, 100853, China
| | - Hanghang Li
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
- Medical School of Chinese PLA, Beijing, 100853, China
| | - Jie Zheng
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China
| | - Fengyu Liu
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China.
| | - You Wan
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China.
| | - Bo Wei
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China.
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Karm MH, Kwon HJ, Shin E, Bae H, Kim YK, Choi SS. Involvement of the spinal γ-aminobutyric acid receptor in the analgesic effects of intrathecally injected hypertonic saline in spinal nerve-ligated rats. Korean J Pain 2023; 36:441-449. [PMID: 37722756 PMCID: PMC10551396 DOI: 10.3344/kjp.23162] [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: 06/02/2023] [Revised: 07/26/2023] [Accepted: 08/05/2023] [Indexed: 09/20/2023] Open
Abstract
Background : Hypertonic saline is used for treating chronic pain; however, clinical studies that aid in optimizing therapeutic protocols are lacking. We aimed to determine the concentration of intrathecally injected hypertonic saline at which the effect reaches its peak as well as the underlying γ-aminobutyric acid (GABA) receptor-related antinociceptive mechanism. Methods : Spinal nerve ligation (SNL; left L5 and L6) was performed to induce neuropathic pain in rats weighing 250-300 g. Experiment 1: one week after implanting the intrathecal catheter, 60 rats were assigned randomly to intrathecal injection with 0.45%, 0.9%, 2.5%, 5%, 10%, and 20% NaCl, followed by behavioral testing at baseline and after 30 minutes, 2 hours, 1 day, and 1 week to determine the minimal concentration which produced maximal analgesia. Experiment 2: after determining the optimal intrathecal hypertonic saline concentration, 60 rats were randomly divided into four groups: Sham, hypertonic saline without pretreatment, and hypertonic saline after pretreatment with one of two GABA receptor antagonists (GABAA [bicuculline], or GABAB [phaclofen]). Behavioral tests were performed at weeks 1 and 3 following each treatment. Results : Hypertonic saline at concentrations greater than 5% alleviated SNL-induced mechanical allodynia and had a significant therapeutic effect, while showing a partial time- and dose-dependent antinociceptive effect on thermal and cold hyperalgesia. However, pretreatment with GABA receptor antagonists inhibited the antinociceptive effect of 5% NaCl. Conclusions : This study indicates that the optimal concentration of hypertonic saline for controlling mechanical allodynia in neuropathic pain is 5%, and that its analgesic effect is related to GABAA and GABAB receptors.
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Affiliation(s)
- Myong-Hwan Karm
- Department of Dental Anesthesiology, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Korea
| | - Hyun-Jung Kwon
- Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Euiyong Shin
- Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Honggyoon Bae
- Department of Anesthesiology and Pain Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea
| | - Young Ki Kim
- Department of Anesthesiology and Pain Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea
| | - Seong-Soo Choi
- Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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Khalilzadeh E, Aliyoldashi M, Abdkarimi B, Azarpey F, Vafaei Saiah G, Hazrati R, Caspani O. Reversal of cold intolerance by testosterone in orchiectomized mice after tibial nerve transection. Behav Brain Res 2023; 441:114269. [PMID: 36574845 DOI: 10.1016/j.bbr.2022.114269] [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: 08/16/2022] [Revised: 11/25/2022] [Accepted: 12/15/2022] [Indexed: 12/25/2022]
Abstract
Cold intolerance is a debilitating effect of nerve injury, has a strong impact on the life of patients and no advisable treatment exists against it. Testosterone influences pain pathways and has analgesic effects. A recent study showed testosterone as being an agonist of TRPM8, the predominant ion channel that contributes to cold hypersensitivity after injury. We investigated the effect of testosterone on cold sensitivity after nerve injury. Specifically, using the double plate test (DPT) (thermo-neutral-plate: 31 ºC and cold-plate: 18 ºC) we determined the thermal preference of mice at different points during the study design consisting of: orchiectomy, tibial nerve transection (TNT) (30 days after orchiectomy), 15-days-repeated subcutaneous injections of testosterone enanthate (250 or 500 µg/kg/day) or vehicle (started 12 h after TNT surgery). Different parameters such as time spent on cold plates, distance traveled, animal speed on the cold- and thermo-neutral-plates were determined in naïve, sham and neuropathic animals. Neither orchiectomy nor sham TNT surgery generate effects on cold intolerance and animal activity while TNT surgery decreased the time spent on the cold-plate and the distance traveled during DPT. Testosterone administration reversed the effect of nerve injury, decreasing the cold hypersensitivity and increasing activity of TNT mice. However, the effect of testosterone on cold avoidance reduced with time and at 14 days after TNT surgery, a higher dose was needed to reverse the effect generated by nerve injury. This indicates that although testosterone administration has a positive effect on cold intolerance, it might not be suitable for prolongated treatment.
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Affiliation(s)
- Emad Khalilzadeh
- Division of physiology, Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran; Neurophysiology Department, Medical Faculty Mannheim of the University of Heidelberg, Mannheim Center for Translational Neuroscience (MCTN), Ludolf-Krehl-Str., 68167 Mannheim, Germany.
| | - Mohammadhassan Aliyoldashi
- Division of physiology, Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Babak Abdkarimi
- Division of physiology, Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Farzin Azarpey
- Division of physiology, Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran; Neurophysiology Department, Medical Faculty Mannheim of the University of Heidelberg, Mannheim Center for Translational Neuroscience (MCTN), Ludolf-Krehl-Str., 68167 Mannheim, Germany
| | - Gholamreza Vafaei Saiah
- Division of physiology, Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Reza Hazrati
- Brain Research Center, Laval University, Quebec, Canada
| | - Ombretta Caspani
- Neurophysiology Department, Medical Faculty Mannheim of the University of Heidelberg, Mannheim Center for Translational Neuroscience (MCTN), Ludolf-Krehl-Str., 68167 Mannheim, Germany
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Liu XG. Normalization of Neuroinflammation: A New Strategy for Treatment of Persistent Pain and Memory/Emotional Deficits in Chronic Pain. J Inflamm Res 2022; 15:5201-5233. [PMID: 36110505 PMCID: PMC9469940 DOI: 10.2147/jir.s379093] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 08/18/2022] [Indexed: 12/12/2022] Open
Abstract
Chronic pain, which affects around 1/3 of the world population and is often comorbid with memory deficit and mood depression, is a leading source of suffering and disability. Studies in past decades have shown that hyperexcitability of primary sensory neurons resulting from abnormal expression of ion channels and central sensitization mediated pathological synaptic plasticity, such as long-term potentiation in spinal dorsal horn, underlie the persistent pain. The memory/emotional deficits are associated with impaired synaptic connectivity in hippocampus. Dysregulation of numerous endogenous proteins including receptors and intracellular signaling molecules is involved in the pathological processes. However, increasing knowledge contributes little to clinical treatment. Emerging evidence has demonstrated that the neuroinflammation, characterized by overproduction of pro-inflammatory cytokines and glial activation, is reliably detected in humans and animals with chronic pain, and is sufficient to induce persistent pain and memory/emotional deficits. The abnormal expression of ion channels and pathological synaptic plasticity in spinal dorsal horn and in hippocampus are resulting from neuroinflammation. The neuroinflammation is initiated and maintained by the interactions of circulating monocytes, glial cells and neurons. Obviously, unlike infectious diseases and cancer, which are caused by pathogens or malignant cells, chronic pain is resulting from alterations of cells and molecules which have numerous physiological functions. Therefore, normalization (counterbalance) but not simple inhibition of the neuroinflammation is the right strategy for treating neuronal disorders. Currently, no such agent is available in clinic. While experimental studies have demonstrated that intracellular Mg2+ deficiency is a common feature of chronic pain in animal models and supplement Mg2+ are capable of normalizing the neuroinflammation, activation of upregulated proteins that promote recovery, such as translocator protein (18k Da) or liver X receptors, has a similar effect. In this article, relevant experimental and clinical evidence is reviewed and discussed.
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Affiliation(s)
- Xian-Guo Liu
- Pain Research Center and Department of Physiology, Zhongshan School of Medicine of Sun Yat-sen University, Guangzhou, People's Republic of China
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The Effect of Ginger and Its Sub-Components on Pain. PLANTS 2022; 11:plants11172296. [PMID: 36079679 PMCID: PMC9460519 DOI: 10.3390/plants11172296] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 08/27/2022] [Accepted: 08/31/2022] [Indexed: 11/16/2022]
Abstract
Zingiber officinale Roscoe (ginger) has long been used as an herbal medicine to treat various diseases, and its main sub-components, [6]-gingerol and [6]-shogaol, were also reported to have anti-inflammatory, anti-oxidant, and anti-tumor effects. However, their effects on various types of pain and their underlying mechanisms of action have not been clearly analyzed and understood yet. Thus, in this review, by analyzing 16 studies that used Z. officinale, [6]-gingerol, and [6]-shogaol on mechanical, spontaneous and thermal pain, their effects and mechanisms of action have been analyzed. Pain was induced by either nerve injury or chemical injections in rodents. Nine studies analyzed the analgesic effect of Z. officinale, and four and three studies focused on [6]-gingerol and [6]-shogaol, respectively. Seven papers have demonstrated the underlying mechanism of action of their analgesic effects. Studies have focused on the spinal cord and one on the dorsal root ganglion (DRG) neurons. Involvement and change in the function of serotonergic receptors (5-HT1A, B, D, and 5A), transient receptor potential vanilloid 1 (TRPV1), N-methyl-D-aspartate (NMDA) receptors, phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2), histone deacetylase 1 (HDAC1), voltage-gated sodium channel 1.8 (Nav1.8), substance P (SP), and sciatic nerve’s morphology have been observed.
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Mirabelli E, Elkabes S. Neuropathic Pain in Multiple Sclerosis and Its Animal Models: Focus on Mechanisms, Knowledge Gaps and Future Directions. Front Neurol 2022; 12:793745. [PMID: 34975739 PMCID: PMC8716468 DOI: 10.3389/fneur.2021.793745] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 11/17/2021] [Indexed: 12/22/2022] Open
Abstract
Multiple sclerosis (MS) is a multifaceted, complex and chronic neurological disease that leads to motor, sensory and cognitive deficits. MS symptoms are unpredictable and exceedingly variable. Pain is a frequent symptom of MS and manifests as nociceptive or neuropathic pain, even at early disease stages. Neuropathic pain is one of the most debilitating symptoms that reduces quality of life and interferes with daily activities, particularly because conventional pharmacotherapies do not adequately alleviate neuropathic pain. Despite advances, the mechanisms underlying neuropathic pain in MS remain elusive. The majority of the studies investigating the pathophysiology of MS-associated neuropathic pain have been performed in animal models that replicate some of the clinical and neuropathological features of MS. Experimental autoimmune encephalomyelitis (EAE) is one of the best-characterized and most commonly used animal models of MS. As in the case of individuals with MS, rodents affected by EAE manifest increased sensitivity to pain which can be assessed by well-established assays. Investigations on EAE provided valuable insights into the pathophysiology of neuropathic pain. Nevertheless, additional investigations are warranted to better understand the events that lead to the onset and maintenance of neuropathic pain in order to identify targets that can facilitate the development of more effective therapeutic interventions. The goal of the present review is to provide an overview of several mechanisms implicated in neuropathic pain in EAE by summarizing published reports. We discuss current knowledge gaps and future research directions, especially based on information obtained by use of other animal models of neuropathic pain such as nerve injury.
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Affiliation(s)
- Ersilia Mirabelli
- Reynolds Family Spine Laboratory, Department of Neurosurgery, New Jersey Medical School, Rutgers the State University of New Jersey, Newark, NJ, United States.,Department of Biology and Chemistry, School of Health Sciences, Liberty University, Lynchburg, VA, United States
| | - Stella Elkabes
- Reynolds Family Spine Laboratory, Department of Neurosurgery, New Jersey Medical School, Rutgers the State University of New Jersey, Newark, NJ, United States
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Chao D, Mecca CM, Yu G, Segel I, Gold MS, Hogan QH, Pan B. Dorsal root ganglion stimulation of injured sensory neurons in rats rapidly eliminates their spontaneous activity and relieves spontaneous pain. Pain 2021; 162:2917-2932. [PMID: 33990112 PMCID: PMC8486885 DOI: 10.1097/j.pain.0000000000002284] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 03/23/2021] [Indexed: 11/26/2022]
Abstract
ABSTRACT Dorsal root ganglion field stimulation (GFS) relieves evoked and spontaneous neuropathic pain by use-dependent blockade of impulse trains through the sensory neuron T-junction, which becomes complete within less than 1 minute for C-type units, also with partial blockade of Aδ units. We used this tool in the spinal nerve ligation (SNL) rat model to selectively block sensory neuron spontaneous activity (SA) of axotomized neurons at the fifth lumbar (L5) level vs blockade of units at the L4 level that remain uninjured but exposed to inflammation. In vivo dorsal root single-unit recordings after SNL showed increased SA in L5 units but not L4 units. Ganglion field stimulation blocked this SA. Ganglion field stimulation delivered at the L5 dorsal root ganglion blocked mechanical hyperalgesia behavior, mechanical allodynia, and ongoing spontaneous pain indicated by conditioned place preference, whereas GFS at L4 blocked evoked pain behavior but not spontaneous pain. In vivo single-unit recordings of spinal cord dorsal horn (DH) wide-dynamic-range neurons showed elevated SA after SNL, which was reduced by GFS at the L5 level but not by GFS at the L4 level. In addition, L5 GFS, but not L4 GFS, increased mechanical threshold of DH units during cutaneous mechanical stimulation, while L5 GFS exceeded L4 GFS in reducing evoked firing rates. Our results indicate that SA in injured neurons supports increased firing of DH wide-dynamic-range neurons, contributing to hyperalgesia, allodynia, and ongoing pain. Ganglion field stimulation analgesic effects after nerve injury are at least partly attributable to blocking propagation of this SA.
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Affiliation(s)
- Dongman Chao
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
| | - Christina M. Mecca
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
| | - Guoliang Yu
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
| | - Ian Segel
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
| | - Michael S. Gold
- Department of Neurobiology, University of Pittsburgh, 3500 Terrace Street Rm E1440 BST, Pittsburgh, PA 15213
| | - Quinn H. Hogan
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
| | - Bin Pan
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
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Abstract
Managing chronic pain remains a major unmet clinical challenge. Patients can be treated with a range of interventions, but pharmacotherapy is the most common. These include opioids, antidepressants, calcium channel modulators, sodium channel blockers, and nonsteroidal anti-inflammatory drugs. Many of these drugs target a particular mechanism; however, chronic pain in many diseases is multifactorial and induces plasticity throughout the sensory neuroaxis. Furthermore, comorbidities such as depression, anxiety, and sleep disturbances worsen quality of life. Given the complexity of mechanisms and symptoms in patients, it is unsurprising that many fail to achieve adequate pain relief from a single agent. The efforts to develop novel drug classes with better efficacy have not always proved successful; a multimodal or combination approach to analgesia is an important strategy in pain control. Many patients frequently take more than one medication, but high-quality evidence to support various combinations is often sparse. Ideally, combining drugs would produce synergistic action to maximize analgesia and reduce side effects, although sub-additive and additive analgesia is still advantageous if additive side-effects can be avoided. In this review, we discuss pain mechanisms, drug actions, and the rationale for mechanism-led treatment selection.Abbreviations: COX - cyclooxygenase, CGRP - calcitonin gene-related peptide, CPM - conditioned pain modulation, NGF - nerve growth factor, NNT - number needed to treat, NMDA - N-methyl-d-aspartate, NSAID - nonsteroidal anti-inflammatory drugs, TCA - tricyclic antidepressant, SNRI - serotonin-noradrenaline reuptake inhibitor, QST - quantitative sensory testing.
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Affiliation(s)
- Ryan Patel
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, UK
| | - Anthony H Dickenson
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, UK
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Sun Z, Meng P, Su C, Ji S, Gao Y, Wang H, Tian J, Li C. PCC-0105002, a novel small molecule inhibitor of PSD95-nNOS protein-protein interactions, attenuates neuropathic pain and corrects motor disorder associated with neuropathic pain model. Toxicol Appl Pharmacol 2021; 429:115698. [PMID: 34428447 DOI: 10.1016/j.taap.2021.115698] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 08/16/2021] [Accepted: 08/18/2021] [Indexed: 01/11/2023]
Abstract
In view of postsynaptic density 95kDA (PSD95) tethers neuronal NO synthase (nNOS) to N-methyl-d-aspartate receptor (NMDAR), the PSD95-nNOS complex represents a therapeutic target of neuropathic pain. This study therefore sought to explore the ability of PCC-0105002, a novel PSD95-nNOS small molecule inhibitor, to alter pain sensitivity in rodent neuropathic pain models. Firstly, the IC50 of PCC-0105002 for PSD95 and NOS1 binding activity was determined using an Alpha Screen assay kit. Then, we examined the effects of PCC-0105002 in the mouse formalin test and in the rat spinal nerve ligation (SNL) model, and explored the ability of PCC-0105002 to mediate analgesia and to effect motor coordination in a rota-rod test. Moreover, the mechanisms whereby PCC-0105002 mediates analgesia was explored via western blotting, Golgi staining, and co-immunoprecipitation experiments in dorsal horn. The outcomes indicated that PCC-0105002 exhibited dose-dependent attenuation of phase II pain-associated behaviors in the formalin test. The result indicated that PCC-0105002 disrupted the PSD95-nNOS interaction with IC50 of 1.408 μM. In the SNL model, PCC-0105002 suppressed mechanical allodynia, thermal hyperalgesia, and abnormal dorsal horn wide dynamic range neuron discharge. PCC-0105002 mediated an analgesic effect comparable to that of MK-801, while it was better able to enhance motor coordination as compared with MK-801. Moreover, PCC-0105002 altered signaling downstream of NMDAR and thus functionally and structurally attenuating synaptic plasticity through respective regulation of the NR2B/GluR1/CaMKIIα and Rac1/RhoA pathways. These findings suggest that the novel PSD95-nNOS inhibitor PCC-0105002 is an effective agent for alleviating neuropathic pain, and that it produces fewer motor coordination-associated side effects than do NMDAR antagonists.
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Affiliation(s)
- Zhihong Sun
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Ping Meng
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Chunyu Su
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Shengmin Ji
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Yonglin Gao
- School of Life Science, Yantai University, Yantai 264005, China
| | - Hongbo Wang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Jingwei Tian
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China.
| | - Chunmei Li
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China.
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Jergova S, Martinez H, Hernandez M, Schachner B, Gross S, Sagen J. Development of a Phantom Limb Pain Model in Rats: Behavioral and Histochemical Evaluation. FRONTIERS IN PAIN RESEARCH 2021; 2:675232. [PMID: 35295448 PMCID: PMC8915728 DOI: 10.3389/fpain.2021.675232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 05/18/2021] [Indexed: 11/13/2022] Open
Abstract
Therapeutic strategies targeting phantom limb pain (PLP) provide inadequate pain relief; therefore, a robust and clinically relevant animal model is necessary. Animal models of PLP are based on a deafferentation injury followed by autotomy behavior. Clinical studies have shown that the presence of pre-amputation pain increases the risk of developing PLP. In the current study, we used Sprague-Dawley male rats with formalin injections or constriction nerve injury at different sites or time points prior to axotomy to mimic clinical scenarios of pre-amputation inflammatory and neuropathic pain. Animals were scored daily for PLP autotomy behaviors, and several pain-related biomarkers were evaluated to discover possible underlying pathological changes. Majority displayed some degree of autotomy behavior following axotomy. Injury prior to axotomy led to more severe PLP behavior compared to animals without preceding injury. Autotomy behaviors were more directed toward the pretreatment insult origin, suggestive of pain memory. Increased levels of IL-1β in cerebrospinal fluid and enhanced microglial responses and the expression of NaV1.7 were observed in animals displaying more severe PLP outcomes. Decreased expression of GAD65/67 was consistent with greater PLP behavior. This study provides a preclinical basis for future understanding and treatment development in the management of PLP.
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Bernal L, Cisneros E, Roza C. Activation of the regeneration-associated gene STAT3 and functional changes in intact nociceptors after peripheral nerve damage in mice. Eur J Pain 2021; 25:886-901. [PMID: 33345380 DOI: 10.1002/ejp.1718] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 12/16/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND In the context of neuropathic pain, the contribution of regeneration to the development of positive symptoms is not completely understood. Several efforts have been done to described changes in axotomized neurons, however, there is scarce data on changes occurring in intact neurons, despite experimental evidence of functional changes. To address this issue, we analysed by immunohistochemistry the presence of phosphorylated signal transducer and activator of transcription 3 (pSTAT3), an accepted marker of regeneration, within DRGs where axotomized neurons were retrogradely labelled following peripheral nerve injury. Likewise, we have characterized abnormal electrophysiological properties in intact fibres after partial nerve injury. METHODS/RESULTS We showed that induction of pSTAT3 in sensory neurons was similar after partial or total transection of the sciatic nerve and to the same extent within axotomized and non-axotomized neurons. We also examined pSTAT3 presence on non-peptidergic and peptidergic nociceptors. Whereas the percentage of neurons marked by IB4 decrease after injury, the proportion of CGRP neurons did not change, but its expression switched from small- to large-diameter neurons. Besides, the percentage of CGRP+ neurons expressing pSTAT3 increased significantly 2.5-folds after axotomy, preferentially in neurons with large diameters. Electrophysiological recordings showed that after nerve damage, most of the neurons with ectopic spontaneous activity (39/46) were non-axotomized C-fibres with functional receptive fields in the skin far beyond the site of damage. CONCLUSIONS Neuronal regeneration after nerve injury, likely triggered from the site of injury, may explain the abnormal functional properties gained by intact neurons, reinforcing their role in neuropathic pain. SIGNIFICANCE Positive symptoms in patients with peripheral neuropathies correlate to abnormal functioning of different subpopulations of primary afferents. Peripheral nerve damage triggers regenerating programs in the cell bodies of axotomized but also in non-axotomized nociceptors which is in turn, develop abnormal spontaneous and evoked discharges. Therefore, intact nociceptors have a significant role in the development of neuropathic pain due to their hyperexcitable peripheral terminals. Therapeutical targets should focus on inhibiting peripheral hyperexcitability in an attempt to limit peripheral and central sensitization.
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Affiliation(s)
- Laura Bernal
- Department of System's Biology, Medical School, University of Alcala, Alcalá de Henares, Spain
| | - Elsa Cisneros
- Department of System's Biology, Medical School, University of Alcala, Alcalá de Henares, Spain.,Health Sciences School, Centro Universitario Internacional de Madrid (CUNIMAD), Madrid, Spain.,Health Sciences School, Universidad Internacional de La Rioja (UNIR), Logroño, Spain
| | - Carolina Roza
- Department of System's Biology, Medical School, University of Alcala, Alcalá de Henares, Spain
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12
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Tran EL, Crawford LK. Revisiting PNS Plasticity: How Uninjured Sensory Afferents Promote Neuropathic Pain. Front Cell Neurosci 2020; 14:612982. [PMID: 33362476 PMCID: PMC7759741 DOI: 10.3389/fncel.2020.612982] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 11/12/2020] [Indexed: 11/13/2022] Open
Abstract
Despite the widespread study of how injured nerves contribute to chronic pain, there are still major gaps in our understanding of pain mechanisms. This is particularly true of pain resulting from nerve injury, or neuropathic pain, wherein tactile or thermal stimuli cause painful responses that are particularly difficult to treat with existing therapies. Curiously, this stimulus-driven pain relies upon intact, uninjured sensory neurons that transmit the signals that are ultimately sensed as painful. Studies that interrogate uninjured neurons in search of cell-specific mechanisms have shown that nerve injury alters intact, uninjured neurons resulting in an activity that drives stimulus-evoked pain. This review of neuropathic pain mechanisms summarizes cell-type-specific pathology of uninjured sensory neurons and the sensory ganglia that house their cell bodies. Uninjured neurons have demonstrated a wide range of molecular and neurophysiologic changes, many of which are distinct from those detected in injured neurons. These intriguing findings include expression of pain-associated molecules, neurophysiological changes that underlie increased excitability, and evidence that intercellular signaling within sensory ganglia alters uninjured neurons. In addition to well-supported findings, this review also discusses potential mechanisms that remain poorly understood in the context of nerve injury. This review highlights key questions that will advance our understanding of the plasticity of sensory neuron subpopulations and clarify the role of uninjured neurons in developing anti-pain therapies.
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Affiliation(s)
- Emily L Tran
- Department of Pathobiological Sciences, University of Wisconsin-Madison School of Veterinary Medicine, Madison, WI, United States
| | - LaTasha K Crawford
- Department of Pathobiological Sciences, University of Wisconsin-Madison School of Veterinary Medicine, Madison, WI, United States
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13
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Yeoh S, Warner WS, Eli I, Mahan MA. Rapid-stretch injury to peripheral nerves: comparison of injury models. J Neurosurg 2020; 135:893-903. [PMID: 33157535 DOI: 10.3171/2020.5.jns193448] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 05/13/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Traditional animal models of nerve injury use controlled crush or transection injuries to investigate nerve regeneration; however, a more common and challenging clinical problem involves closed traction nerve injuries. The authors have produced a precise traction injury model and sought to examine how the pathophysiology of stretch injuries compares with that of crush and transection injuries. METHODS Ninety-five late-adolescent (8-week-old) male mice underwent 1 of 7 injury grades or a sham injury (n > 10 per group): elastic stretch, inelastic stretch, stretch rupture, crush, primary coaptation, secondary coaptation, and critical gap. Animals underwent serial neurological assessment with sciatic function index, tapered beam, and von Frey monofilament testing for 48 days after injury, followed by trichrome and immunofluorescent nerve histology and muscle weight evaluation. RESULTS The in-continuity injuries, crush and elastic stretch, demonstrated different recovery profiles, with more severe functional deficits after crush injury than after elastic stretch immediately following injury (p < 0.05). However, animals with either injury type returned to baseline performance in all neurological assessments, accompanied by minimal change in nerve histology. Inelastic stretch, a partial discontinuity injury, produced more severe neurological deficits, incomplete return of function, 47% ± 9.1% (mean ± SD) reduction of axon counts (p < 0.001), and partial neuroma formation within the nerve. Discontinuity injuries, including immediate and delayed nerve repair, stretch rupture, and critical gap, manifested severe, long-term neurological deficits and profound axonal loss, coupled with intraneural scar formation. Although repaired nerves demonstrated axon regeneration across the gap, rupture and critical gap injuries demonstrated negligible axon crossing, despite rupture injuries having healed into continuity. CONCLUSIONS Stretch-injured nerves present unique pathology and functional deficits compared with traditional nerve injury models. Because of the profound neuroma formation, stretch injuries represent an opportunity to study the pathophysiology associated with clinical injury mechanisms. Further validation for comparison with human injuries will require evaluation in a large-animal model.
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14
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Li C, Su C, Wang Z, Han R, Wang Y, Wang H, Tian J, Gao Y. WITHDRAWN: PCC-0105002, a novel small molecule inhibitor of PSD95-nNOS protein-protein interactions, attenuates neuropathic pain and corrects motor coordination-associated side effects in neuropathic pain model. Toxicol Appl Pharmacol 2020:115208. [PMID: 32828906 DOI: 10.1016/j.taap.2020.115208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/06/2020] [Accepted: 08/18/2020] [Indexed: 11/28/2022]
Abstract
This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.
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Affiliation(s)
- Chunmei Li
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Chunyu Su
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Zhezhe Wang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Rui Han
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Yu Wang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Hongbo Wang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Jingwei Tian
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China.
| | - Yonglin Gao
- School of Life Science, Yantai University, Yantai 264005, China.
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15
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Dendritic Spine Dynamics after Peripheral Nerve Injury: An Intravital Structural Study. J Neurosci 2020; 40:4297-4308. [PMID: 32371602 DOI: 10.1523/jneurosci.2858-19.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 02/10/2020] [Accepted: 02/28/2020] [Indexed: 11/21/2022] Open
Abstract
Neuropathic pain is an intractable medical condition with few or no options for effective treatment. Emerging evidence shows a strong structure-function relationship between dendritic spine dysgenesis and the presence of neuropathic pain. Postmortem tissue analyses can only imply dynamic structural changes associated with injury-induced pain. Here, we profiled the in vivo dynamics of dendritic spines over time on the same superficial dorsal horn (lamina II) neurons before and after peripheral nerve injury-induced pain. We used a two-photon, whole-animal imaging paradigm that permitted repeat imaging of the same dendritic branches of these neurons in C57/Bl6 Thy1-YFP male mice. Our study demonstrates, for the first time, the ongoing, steady-state changes in dendritic spine dynamics in the dorsal horn associated with peripheral nerve injury and pain. Ultimately, the relationship between altered dendritic spine dynamics and neuropathic pain may serve as a structure-based opportunity to investigate mechanisms of pain following injury and disease.SIGNIFICANCE STATEMENT This work is important because it demonstrates for the first time: (1) the powerful utility of intravital study of dendritic spine dynamics in the superficial dorsal horn; (2) that nerve injury-induced pain triggers changes in dendritic spine steady-state behavior in the spinal cord dorsal horn; and (3) this work opens the door to further investigations in vivo of spinal cord dendritic spine dynamics in the context of injury and disease.
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16
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Hara R, Asaoka Y, Takahashi D, Nomura H, Amano T, Minami M. Disappearance of the inhibitory effect of neuropeptide Y within the dorsolateral bed nucleus of the stria terminalis in rats with chronic pain. Neurosci Lett 2020; 728:134958. [PMID: 32278943 DOI: 10.1016/j.neulet.2020.134958] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 03/25/2020] [Accepted: 04/04/2020] [Indexed: 01/24/2023]
Abstract
We recently showed that the mesolimbic dopaminergic system was tonically suppressed during chronic pain by enhanced corticotropin releasing factor (CRF) signaling within the dorsolateral bed nucleus of the stria terminalis (dlBNST), and that inhibition of intra-dlBNST CRF signaling restored the mesolimbic dopaminergic system function. Specifically, bilateral intra-dlBNST injections of the CRF type 1 receptor antagonist NBI27914 increased intra-nucleus accumbens dopamine release and induced reward-related behaviors in rats with chronic pain. Here, we used a conditioned place preference (CPP) test to explore whether intra-dlBNST injections of neuropeptide Y (NPY) restored the mesolimbic reward system function in chronic pain rats, because we previously showed that NPY had an effect opposite to that of CRF in dlBNST neurons. Specifically, CRF depolarized type II dlBNST neurons whereas NPY hyperpolarized them. However, unexpectedly, intra-dlBNST NPY injections had no effect on CPP test outcomes. Then, we compared the effects of NPY on the membrane potentials of type II dlBNST neurons of sham-operated control rats and those of chronic pain animals. Whole-cell patch-clamp electrophysiology revealed that NPY hyperpolarized type II dlBNST neurons in the sham-operated group. By contrast, in the chronic pain group, NPY did not hyperpolarize, but rather depolarized, type II dlBNST neurons. These results indicate that NPY no longer hyperpolarizes type II dlBNST neurons in rats with chronic pain, therefore it does not reverse the excitatory effects of CRF. This may be why intra-dlBNST injections of NPY into chronic pain rats did not exhibit a rewarding effect in the CPP test, whereas intra-dlBNST injections of NBI27914 did. This is the first study to demonstrate a chronic pain-induced neuroplastic change in NPY signaling in the dlBNST. Such a change may be involved in the dysfunction of the mesolimbic reward system under the chronic pain condition.
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Affiliation(s)
- Ryuto Hara
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Yuta Asaoka
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Daiki Takahashi
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Hiroshi Nomura
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Taiju Amano
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Masabumi Minami
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
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17
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Retroperitoneal Approach for Ilioinguinal, Iliohypogastric, and Genitofemoral Neurectomies in the Treatment of Refractory Groin Pain After Inguinal Hernia Repair. Ann Plast Surg 2020; 84:431-435. [DOI: 10.1097/sap.0000000000002226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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18
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Takamura H, Terashima T, Mori K, Katagi M, Okano J, Suzuki Y, Imai S, Kojima H. Bone-Marrow-Derived Mononuclear Cells Relieve Neuropathic Pain after Spinal Nerve Injury in Mice. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2020; 17:657-665. [PMID: 32322604 PMCID: PMC7160523 DOI: 10.1016/j.omtm.2020.03.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 03/23/2020] [Indexed: 12/19/2022]
Abstract
Treating neuropathic pain is a critical clinical issue. Although numerous therapies have been proposed, effective treatments have not been established. Therefore, safe and feasible treatment methods are urgently needed. In this study, we investigated the therapeutic effects of autologous intrathecal administration of bone-marrow-derived mononuclear cells (MNCs) on neuropathic pain. We generated a mouse model of neuropathic pain by transecting the spinal nerve and evaluated neuropathic pain by measuring the mechanical threshold in the following 14 days. Mice in the MNC injection group had a higher mechanical threshold than those in the buffer group. We assessed the effect of MNC treatment on the dorsal root ganglia and spinal cord by immunohistochemistry, mRNA expression, and cytokine assay. The migration and accumulation of microglia were significantly suppressed in the MNC group, and the mRNA expression of inflammatory cytokines such as interleukin (IL)-6, IL-1β, and tumor necrosis factor alpha (TNF-α) was markedly downregulated. Furthermore, MNC administration tended to suppress various cytokines in the cerebrospinal fluid of the model mice. In conclusion, our results suggest that intrathecal injection of MNCs relieves neuropathic pain and might be a promising cell therapy for the treatment of this condition.
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Affiliation(s)
- Hiroshi Takamura
- Department of Stem Cell Biology and Regenerative Medicine, Shiga University of Medical Science, Shiga 520-2192, Japan.,Department of Orthopedic Surgery, Shiga University of Medical Science, Shiga, Japan
| | - Tomoya Terashima
- Department of Stem Cell Biology and Regenerative Medicine, Shiga University of Medical Science, Shiga 520-2192, Japan
| | - Kanji Mori
- Department of Orthopedic Surgery, Shiga University of Medical Science, Shiga, Japan
| | - Miwako Katagi
- Department of Stem Cell Biology and Regenerative Medicine, Shiga University of Medical Science, Shiga 520-2192, Japan
| | - Junko Okano
- Department of Plastic and Reconstructive Surgery, Shiga University of Medical Science, Shiga, Japan
| | - Yoshihisa Suzuki
- Department of Plastic and Reconstructive Surgery, Shiga University of Medical Science, Shiga, Japan
| | - Shinji Imai
- Department of Orthopedic Surgery, Shiga University of Medical Science, Shiga, Japan
| | - Hideto Kojima
- Department of Stem Cell Biology and Regenerative Medicine, Shiga University of Medical Science, Shiga 520-2192, Japan
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19
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Anti-hypernociceptive effects of methanol extract of Boswellia dalzielii on STZ-induced diabetic neuropathic pain. ADVANCES IN TRADITIONAL MEDICINE 2020. [DOI: 10.1007/s13596-019-00411-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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20
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Ding YQ, Luo H, Qi JG. MHCII-restricted T helper cells: an emerging trigger for chronic tactile allodynia after nerve injuries. J Neuroinflammation 2020; 17:3. [PMID: 31900220 PMCID: PMC6942353 DOI: 10.1186/s12974-019-1684-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 12/19/2019] [Indexed: 02/08/2023] Open
Abstract
Nerve injury-induced chronic pain has been an urgent problem for both public health and clinical practice. While transition to chronic pain is not an inevitable consequence of nerve injuries, the susceptibility/resilience factors and mechanisms for chronic neuropathic pain after nerve injuries still remain unknown. Current preclinical and clinical studies, with certain notable limitations, have shown that major histocompatibility complex class II–restricted T helper (Th) cells is an important trigger for nerve injury-induced chronic tactile allodynia, one of the most prevalent and intractable clinical symptoms of neuropathic pain. Moreover, the precise pathogenic neuroimmune interfaces for Th cells remain controversial, not to mention the detailed pathogenic mechanisms. In this review, depending on the biology of Th cells in a neuroimmunological perspective, we summarize what is currently known about Th cells as a trigger for chronic tactile allodynia after nerve injuries, with a focus on identifying what inconsistencies are evident. Then, we discuss how an interdisciplinary perspective would improve the understanding of Th cells as a trigger for chronic tactile allodynia after nerve injuries. Finally, we hope that the expected new findings in the near future would translate into new therapeutic strategies via targeting Th cells in the context of precision medicine to either prevent or reverse chronic neuropathic tactile allodynia.
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Affiliation(s)
- You-Quan Ding
- Department of Histology, Embryology and Neurobiology, West China School of Basic Medical Sciences and Forensic Medicine, Sichuan University, No 17, Section 3, South Ren-min road, Chengdu, 610041, Sichuan, China
| | - Han Luo
- Department of Thyroid and Parathyroid Surgery, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jian-Guo Qi
- Department of Histology, Embryology and Neurobiology, West China School of Basic Medical Sciences and Forensic Medicine, Sichuan University, No 17, Section 3, South Ren-min road, Chengdu, 610041, Sichuan, China.
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21
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Takahashi D, Asaoka Y, Kimura K, Hara R, Arakaki S, Sakasai K, Suzuki H, Yamauchi N, Nomura H, Amano T, Minami M. Tonic Suppression of the Mesolimbic Dopaminergic System by Enhanced Corticotropin-Releasing Factor Signaling Within the Bed Nucleus of the Stria Terminalis in Chronic Pain Model Rats. J Neurosci 2019; 39:8376-8385. [PMID: 31451580 PMCID: PMC6794933 DOI: 10.1523/jneurosci.3047-18.2019] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 07/01/2019] [Accepted: 08/16/2019] [Indexed: 02/02/2023] Open
Abstract
Although dysfunction of the mesolimbic dopaminergic system has been implicated in chronic pain, the underlying mechanisms remain to be elucidated. We hypothesized that increased inhibitory inputs to the neuronal pathway from the dorsolateral bed nucleus of the stria terminalis (dlBNST) to the ventral tegmental area (VTA) during chronic pain may induce tonic suppression of the mesolimbic dopaminergic system. To test this hypothesis, male Sprague Dawley rats were subjected to spinal nerve ligation to induce neuropathic pain and then spontaneous IPSCs (sIPSCs) were measured in this neuronal pathway. Whole-cell patch-clamp electrophysiology of brain slices containing the dlBNST revealed that the frequency of sIPSCs significantly increased in VTA-projecting dlBNST neurons 4 weeks after surgery. Next, the role of corticotropin-releasing factor (CRF) signaling within the dlBNST in the increased sIPSCs was examined. CRF increased the frequency of sIPSCs in VTA-projecting dlBNST neurons in sham-operated controls, but not in chronic pain rats. By contrast, NBI27914, a CRF type 1 receptor antagonist, decreased the frequency of sIPSCs in VTA-projecting dlBNST neurons in the chronic pain rats, but not in the control animals. In addition, histological analyses revealed the increased expression of CRF mRNA in the dlBNST. Finally, bilateral injections of NBI27914 into the dlBNST of chronic pain rats activated mesolimbic dopaminergic neurons and induced conditioned place preference. Together, these results suggest that the mesolimbic dopaminergic system is tonically suppressed during chronic pain by enhanced CRF signaling within the dlBNST via increased inhibitory inputs to VTA-projecting dlBNST neurons.SIGNIFICANCE STATEMENT The comorbidity of chronic pain and depression has long been recognized. Although dysfunction of the mesolimbic dopaminergic system has been implicated in both chronic pain and depression, the underlying mechanisms remain to be elucidated. Here, we show that the inhibitory inputs to the neuronal pathway from the dorsolateral bed nucleus of the stria terminalis (dlBNST) to the ventral tegmental area increase during chronic pain. This neuroplastic change is mediated by enhanced corticotropin-releasing factor signaling within the dlBNST that leads to tonic suppression of the mesolimbic dopaminergic system, which may be involved in the depressive mood and anhedonia under the chronic pain condition.
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Affiliation(s)
- Daiki Takahashi
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Yuta Asaoka
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Keisuke Kimura
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Ryuto Hara
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Saya Arakaki
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Keisuke Sakasai
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Hiroe Suzuki
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Naoki Yamauchi
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Hiroshi Nomura
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Taiju Amano
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Masabumi Minami
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
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22
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Abstract
A consensus on the optimal treatment of painful neuromas does not exist. Our objective was to identify available data and to examine the role of surgical technique on outcomes following surgical management of painful neuromas. In accordance with the PRISMA guidelines, we performed a comprehensive literature search to identify studies measuring the efficacy of the surgical treatment of painful neuromas in the extremities (excluding Morton's neuroma and compression neuropathies). Surgical treatments were categorized as excision-only, excision and transposition, excision and cap, excision and repair, or neurolysis and coverage. Data on the proportion of patients with a meaningful reduction in pain were pooled and a random-effects meta-analysis was performed. The effects of confounding, study quality, and publication bias were examined with stratified, meta-regression, and bias analysis. Fifty-four articles met the inclusion criteria, many with multiple treatment groups. Outcomes reporting varied significantly and few studies controlled for confounding. Overall, surgical treatment of neuroma pain was effective in 77% of patients [95% confidence interval: 73-81]. No significant differences were seen between surgical techniques. Among studies with a mean pain duration greater than 24 months, or median number of operations greater than 2 prior to definitive neuroma pain surgery, excision and transposition or neurolysis and coverage were significantly more likely than other operative techniques to result in a meaningful reduction in pain (P < 0.05). Standardization in the reporting of surgical techniques, outcomes, and confounding factors is needed in future studies to enable providers to make comparisons across disparate techniques in the surgical treatment of neuroma pain.
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Mbiantcha M, Khalid R, Dawe A, Mehreen A, Atsamo DA, Ateufack G, Hamza D, Nana WY, Bomba FTD, Naeem RU, Izhar A. Antihypernociceptive and neuroprotective effects of Combretin A and Combretin B on streptozotocin-induced diabetic neuropathy in mice. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2019; 392:697-713. [DOI: 10.1007/s00210-019-01626-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 01/29/2019] [Indexed: 11/29/2022]
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24
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Duerr ER, Chang A, Venkateswaran N, Goldhardt R, Levitt RC, Gregori NZ, Sarantopoulos CD, Galor A. Resolution of pain with periocular injections in a patient with a 7-year history of chronic ocular pain. Am J Ophthalmol Case Rep 2019; 14:35-38. [PMID: 30815622 PMCID: PMC6378870 DOI: 10.1016/j.ajoc.2019.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 11/22/2018] [Accepted: 02/04/2019] [Indexed: 12/26/2022] Open
Abstract
Purpose We report a case of a male patient with chronic ocular pain that resolved completely following peripheral nerve blocks. Observations A 66-year-old male presented with a seven-year history of severe left eye pain and photophobia. The pain began after retinal detachment repair with scleral buckle placement. Previous treatments included topical (autologous serum tears, corticosteroids, diclofenac, cyclosporine) and oral (gabapentin, diclofenac) therapies with no pain relief. The patient's pain was so severe that he requested enucleation. After discussion, the decision was made to perform periocular nerve blocks. Prior to the procedure, the patient reported an average pain intensity of 8 out of 10 and photophobia daily. Following left supraorbital, supratrochlear, infraorbital and infratrochlear injections with bupivacaine and methylprednisolone, pain intensity and photophobia improved to 1–2 out of 10. One week later, repeat infraorbital and infratrochlear nerve blocks were given, after which time the patient reported complete resolution of symptoms that lasted for 7 months. Repeat nerve blocks were administered with repeat resolution of pain. There were no complications associated with the procedures. Conclusions and Importance Chronic ocular pain can be a debilitating condition. Periorbital nerve blocks can provide pain relief and should be considered as a potential treatment option after medical management has failed.
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Affiliation(s)
- Eric Rh Duerr
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami, 900 NW 17th Street, Miami, FL, 33136, USA
| | - Andrew Chang
- Department of Physical Medicine and Rehabilitation, University of Miami/Jackson Memorial Hospital, 1800 NW 10th Ave, Miami, FL, 33136, USA
| | - Nandini Venkateswaran
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami, 900 NW 17th Street, Miami, FL, 33136, USA
| | - Raquel Goldhardt
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami, 900 NW 17th Street, Miami, FL, 33136, USA.,Miami Veterans Administration Medical Center, 1201 NW 16th St, Miami, FL, 33125, USA
| | - Roy C Levitt
- Department of Pain Management, University of Miami, 1120 NW 14th St, Miami, FL, 33136, USA
| | - Ninel Z Gregori
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami, 900 NW 17th Street, Miami, FL, 33136, USA.,Miami Veterans Administration Medical Center, 1201 NW 16th St, Miami, FL, 33125, USA
| | | | - Anat Galor
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami, 900 NW 17th Street, Miami, FL, 33136, USA.,Miami Veterans Administration Medical Center, 1201 NW 16th St, Miami, FL, 33125, USA
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25
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Gintzler AR, Liu NJ, Storman EM, Wessendorf MW. Exploiting endogenous opioids: Lessons learned from endomorphin 2 in the female rat. Peptides 2019; 112:133-138. [PMID: 30557590 PMCID: PMC7173356 DOI: 10.1016/j.peptides.2018.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 11/30/2018] [Accepted: 12/03/2018] [Indexed: 02/06/2023]
Abstract
Effective management of chronic pain is demanded by ethical as well as medical considerations. Although opioid analgesics remain among the most effective pharmacotherapies for ameliorating many types of pain, their use is clouded by concerns regarding their addictive properties, underscored by the current epidemic of prescription opioid abuse and attendant deaths. Medicinal harnessing of endogenous opioid antinociception could provide a strategy for continuing to take advantage of the powerful antinociceptive properties of opioids while avoiding their abuse potential. Based on our studies of endogenous mechanism that suppress and facilitate spinal endomorphin 2 antinociception over the rat reproductive cycle, we identified multiple signaling molecules that could serve as targets for activating endogenous opioid analgesia for chronic pain management in women. Our findings emphasize the need for a precision medicine approach that includes stage of menstrual cycle as an important determinant of drug targets for (activating/harnessing) endogenous opioid antinociceptive systems/ capabilities. Utilization of drugs that harness endogenous opioid antinociception in accordance with varying physiological states represents a novel approach for effective pain management.
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Affiliation(s)
- Alan R Gintzler
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY, 11203, USA.
| | - Nai-Jiang Liu
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY, 11203, USA
| | - Emiliya M Storman
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY, 11203, USA
| | - Martin W Wessendorf
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, MN 55455, USA
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Abstract
Pain is a frequent cause of physician visits. Many physicians find these patients challenging because they often have complicated histories, emotional comorbidities, confusing examinations, difficult problems to fix, and the possibility of factitious complaints for attention or narcotic pain medications. As a result, many patients are lumped into the category of chronic, centralized pain and relegated to pain management. However, recent literature suggests that surgical management of carefully diagnosed generators of pain can greatly reduce patients' pain and narcotic requirements. This article reviews recent literature on surgical management of pain and four specific sources of chronic pain amenable to surgical treatment: painful neuroma, nerve compression, myofascial/musculoskeletal pain, and complex regional pain syndrome type II.
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Affiliation(s)
- Louis H Poppler
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA.
| | - Susan E Mackinnon
- Division of Plastic and Reconstructive Surgery, Washington University in St. Louis, St. Louis, MO, USA
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Patel R, Kucharczyk M, Montagut‐Bordas C, Lockwood S, Dickenson AH. Neuropathy following spinal nerve injury shares features with the irritable nociceptor phenotype: A back-translational study of oxcarbazepine. Eur J Pain 2019; 23:183-197. [PMID: 30091265 PMCID: PMC6396087 DOI: 10.1002/ejp.1300] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 07/24/2018] [Accepted: 07/31/2018] [Indexed: 12/30/2022]
Abstract
BACKGROUND The term 'irritable nociceptor' was coined to describe neuropathic patients characterized by evoked hypersensitivity and preservation of primary afferent fibres. Oxcarbazepine is largely ineffectual in an overall patient population, but has clear efficacy in a subgroup with the irritable nociceptor profile. We examine whether neuropathy in rats induced by spinal nerve injury shares overlapping pharmacological sensitivity with the irritable nociceptor phenotype using drugs that target sodium channels. METHODS In vivo electrophysiology was performed in anaesthetized spinal nerve ligated (SNL) and sham-operated rats to record from wide dynamic range (WDR) neurones in the ventral posterolateral thalamus (VPL) and dorsal horn. RESULTS In neuropathic rats, spontaneous activity in the VPL was substantially attenuated by spinal lidocaine, an effect that was absent in sham rats. The former measure was in part dependent on ongoing peripheral activity as intraplantar lidocaine also reduced aberrant spontaneous thalamic firing. Systemic oxcarbazepine had no effect on wind-up of dorsal horn neurones in sham and SNL rats. However, in SNL rats, oxcarbazepine markedly inhibited punctate mechanical-, dynamic brush- and cold-evoked neuronal responses in the VPL and dorsal horn, with minimal effects on heat-evoked responses. In addition, oxcarbazepine inhibited spontaneous activity in the VPL. Intraplantar injection of the active metabolite licarbazepine replicated the effects of systemic oxcarbazepine, supporting a peripheral locus of action. CONCLUSIONS We provide evidence that ongoing activity in primary afferent fibres drives spontaneous thalamic firing after spinal nerve injury and that oxcarbazepine through a peripheral mechanism exhibits modality-selective inhibitory effects on sensory neuronal processing. SIGNIFICANCE The inhibitory effects of lidocaine and oxcarbazepine in this rat model of neuropathy resemble the clinical observations in the irritable nociceptor patient subgroup and support a mechanism-based rationale for bench-to-bedside translation when screening novel drugs.
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Affiliation(s)
- Ryan Patel
- Department of Neuroscience, Physiology and PharmacologyUniversity College LondonLondonUK
| | - Mateusz Kucharczyk
- Department of Neuroscience, Physiology and PharmacologyUniversity College LondonLondonUK
| | | | - Stevie Lockwood
- Department of Neuroscience, Physiology and PharmacologyUniversity College LondonLondonUK
| | - Anthony H. Dickenson
- Department of Neuroscience, Physiology and PharmacologyUniversity College LondonLondonUK
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Yu H, Shin SM, Wang F, Xu H, Xiang H, Cai Y, Itson-Zoske B, Hogan QH. Transmembrane protein 100 is expressed in neurons and glia of dorsal root ganglia and is reduced after painful nerve injury. Pain Rep 2018; 4:e703. [PMID: 30801043 PMCID: PMC6370145 DOI: 10.1097/pr9.0000000000000703] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 10/08/2018] [Accepted: 10/30/2018] [Indexed: 12/16/2022] Open
Abstract
Introduction Tmem100 modulates interactions between TRPA1 and TRPV1. The cell specificity of Tmem100 expression in dorsal root ganglia (DRGs) is not well defined, nor is the effect of peripheral nerve injury on Tmem100 expression. Objective This study was designed to determine the cell specificity of Tmem100 expression in DRG and its subcellular localization, and to examine how Tmem100 expression may be altered in painful conditions. Methods Dorsal root ganglion Tmem100 expression was determined by immunohistochemistry, immunoblot, and quantitative real-time PCR, and compared between various experimental rat pain models and controls. Results Tmem100 is expressed in both neurons and perineuronal glial cells in the rat DRG. The plasma membrane and intracellular localization of Tmem100 are identified in 83% ± 6% of IB4-positive and 48% ± 6% of calcitonin gene-related peptide-positive neurons, as well as in medium- and large-sized neurons, with its immunopositivity colocalized to TRPV1 (94% ± 5%) and TRPA1 (96% ± 3%). Tmem100 is also detected in the perineuronal satellite glial cells and in some microglia. Tmem100 protein is significantly increased in the lumbar DRGs in the complete Freund adjuvant inflammatory pain. By contrast, peripheral nerve injury by spinal nerve ligation diminishes Tmem100 expression in the injured DRG, with immunoblot and immunohistochemistry experiments showing reduced Tmem100 protein levels in both neurons and satellite glial cells of DRGs proximal to injury, whereas Tmem100 is unchanged in adjacent DRGs. The spared nerve injury model also reduces Tmem100 protein in the injured DRGs. Conclusion Our data demonstrate a pain pathology-dependent alteration of DRG Tmem100 protein expression, upregulated during CFA inflammatory pain but downregulated during neuropathic pain.
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Affiliation(s)
- Hongwei Yu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Zablocki Veterans Affairs Medical Center, Milwaukee, WI, USA
| | - Seung Min Shin
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Fei Wang
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Medical Experiment Center, Shaanxi University of Chinese Medicine, Xianyang, Shaanxi, PR of China
| | - Hao Xu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Department of Orthopedic Surgery, Affiliated Hospital of Qingdao University, Qingdao, PR of China
| | - Hongfei Xiang
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Department of Orthopedic Surgery, Affiliated Hospital of Qingdao University, Qingdao, PR of China
| | - Yongsong Cai
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, PR of China
| | - Brandon Itson-Zoske
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Quinn H Hogan
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Zablocki Veterans Affairs Medical Center, Milwaukee, WI, USA
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Liu NJ, Storman EM, Gintzler AR. Pharmacological Modulation of Endogenous Opioid Activity to Attenuate Neuropathic Pain in Rats. THE JOURNAL OF PAIN 2018; 20:235-243. [PMID: 30366152 DOI: 10.1016/j.jpain.2018.10.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/12/2018] [Accepted: 10/17/2018] [Indexed: 12/23/2022]
Abstract
We showed previously that spinal metabotropic glutamate receptor 1 (mGluR1) signaling suppresses or facilitates (depending on the stage of estrous cycle) analgesic responsiveness to intrathecal endomorphin 2, a highly mu-opioid receptor-selective endogenous opioid. Spinal endomorphin 2 antinociception is suppressed during diestrus by mGluR1 when it is activated by membrane estrogen receptor alpha (mERα) and is facilitated during proestrus when mGluR1 is activated by glutamate. In the current study, we tested the hypothesis that in female rats subjected to spinal nerve ligation (SNL), the inhibition of spinal estrogen synthesis or blockade of spinal mERα/mGluR1 would be antiallodynic during diestrus, whereas during proestrus, mGluR1 blockade would worsen the mechanical allodynia. As postulated, following SNL, aromatase inhibition or mERα/mGluR1 blockade during diestrus markedly lessened the mechanical allodynia. This was observed only on the paw ipsilateral to SNL and was eliminated by naloxone, implicating endogenous opioid mediation. In contrast, during proestrus, mGluR1 blockade worsened the SNL-induced mechanical allodynia of the ipsilateral paw. Findings suggest menstrual cycle stage-specific drug targets for and the putative clinical utility of harnessing endogenous opioids for chronic pain management in women, as well as the value of, if not the necessity for, considering menstrual cycle stage in clinical trials thereof. PERSPECTIVE: Intrathecal treatments that enhance spinal endomorphin 2 analgesic responsiveness under basal conditions lessen mechanical allodynia in a chronic pain model. Findings provide a foundation for developing drugs that harness endogenous opioid antinociception for chronic pain relief, lessening the need for exogenous opioids and thus prescription opioid abuse.
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Affiliation(s)
- Nai-Jiang Liu
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, Brooklyn, New York
| | - Emiliya M Storman
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, Brooklyn, New York
| | - Alan R Gintzler
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, Brooklyn, New York..
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de Moraes AA, de Almeida CAS, Lucas G, Thomazini JA, DeMaman AS. Effect of swimming training on nerve morphological recovery after compressive injury. Neurol Res 2018; 40:955-962. [PMID: 30091393 DOI: 10.1080/01616412.2018.1504180] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE This study aims to investigate morphological alterations caused by partial sciatic nerve ligation (PNL) and the efficacy of a moderate-intensity swimming training as therapeutic strategy for nerve regeneration. METHODS A number of 30 male adult mice were equally divided in control, 14 days after PNL (PNL 14 days), 42 days after PNL (PNL 42 days), 70 days after PNL (PNL 70 days) and 5-week exercise training after 7 days post-lesion (PNL trained 35 days) groups. PNL trained 35 days group began with a 10-min session for 3 days and this time was gradually increased by 10 min every three sessions until the animals had swum for 50 min per session. Morphoquantitative analysis was carried out to assess nerve regeneration in each group. RESULTS PNL 14 days group exhibited less degenerating signs than PNL 42 days group, where most post-lesion alterations were visualized. Nerve area and minimum diameter were significantly lower (p < 0.05) than control group. PNL 70 days group showed a greater degree of regenerating fibers and similar morphometric parameters to control group. PNL trained 35 days demonstrated signs of regeneration, reaching control group values in the morphometric analysis. DISCUSSION PNL promotes great histopathological changes, which became more visible at 42 post-injury days. A natural nerve-regeneration tendency was observed throughout time, as observed in PNL 70 days group; nevertheless, moderate swimming training was found to be a therapeutic resource for nerve regeneration, accelerating such process from a morphoquantitative perspective. ABBREVIATIONS ANOVA: One-way analysis of variance; BDNF: Brain-derived neurotrophic factor; FGF-2: Fibroblast growth factor 2; GDNF: Glial cell line derived neurotrophic factor; IGF: Insulin-link growth factor; IL-1β: Interleukin-1β; NGF: Neural growth factor; PBS: Phosphate-buffered saline; PNL: Partial sciatic nerve ligation.
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Affiliation(s)
- Alexa Alves de Moraes
- a Department of Physiotherapy, Center of Biological and Health Sciences , Paraíba State University , Campina Grande , Brazil
| | | | - Guilherme Lucas
- c Department of Physiology, Ribeirão Preto School of Medicine , University of São Paulo , Ribeirão Preto , Brazil
| | - José Antonio Thomazini
- d Department of Surgery and Anatomy, Ribeirão Preto School of Medicine , University of São Paulo , Ribeirão Preto , Brazil
| | - Aline Santos DeMaman
- e Department of Biology, Center of Biological and Health Sciences , Paraíba State University , Campina Grande , Brazil
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31
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Yang J, Xie MX, Hu L, Wang XF, Mai JZ, Li YY, Wu N, Zhang C, Li J, Pang RP, Liu XG. Upregulation of N-type calcium channels in the soma of uninjured dorsal root ganglion neurons contributes to neuropathic pain by increasing neuronal excitability following peripheral nerve injury. Brain Behav Immun 2018; 71:52-65. [PMID: 29709527 DOI: 10.1016/j.bbi.2018.04.016] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 04/24/2018] [Accepted: 04/26/2018] [Indexed: 01/05/2023] Open
Abstract
N-type voltage-gated calcium (Cav2.2) channels are expressed in the central terminals of dorsal root ganglion (DRG) neurons, and are critical for neurotransmitter release. Cav2.2 channels are also expressed in the soma of DRG neurons, where their function remains largely unknown. Here, we showed that Cav2.2 was upregulated in the soma of uninjured L4 DRG neurons, but downregulated in those of injured L5 DRG neurons following L5 spinal nerve ligation (L5-SNL). Local application of specific Cav2.2 blockers (ω-conotoxin GVIA, 1-100 μM or ZC88, 10-1000 μM) onto L4 and 6 DRGs on the operated side, but not the contralateral side, dose-dependently reversed mechanical allodynia induced by L5-SNL. Patch clamp recordings revealed that both ω-conotoxin GVIA (1 μM) and ZC88 (10 μM) depressed hyperexcitability in L4 but not in L5 DRG neurons of L5-SNL rats. Consistent with this, knockdown of Cav2.2 in L4 DRG neurons with AAV-Cav2.2 shRNA substantially prevented L5-SNL-induced mechanical allodynia and hyperexcitability of L4 DRG neurons. Furthermore, in L5-SNL rats, interleukin-1 beta (IL-1β) and IL-10 were upregulated in L4 DRGs and L5 DRGs, respectively. Intrathecal injection of IL-1β induced mechanical allodynia and Cav2.2 upregulation in bilateral L4-6 DRGs of naïve rats, whereas injection of IL-10 substantially prevented mechanical allodynia and Cav2.2 upregulation in L4 DRGs in L5-SNL rats. Finally, in cultured DRG neurons, Cav2.2 was dose-dependently upregulated by IL-1β and downregulated by IL-10. These data indicate that the upregulation of Cav2.2 in uninjured DRG neurons via IL-1β over-production contributes to neuropathic pain by increasing neuronal excitability following peripheral nerve injury.
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Affiliation(s)
- Jie Yang
- Pain Research Center and Department of Physiology, Zhongshan School of Medicine of Sun Yat-sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Man-Xiu Xie
- Department of Anesthesiology, Cancer Center, Sun Yat-sen University, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, East 651 Dongfeng Rd, Guangzhou 510060, China
| | - Li Hu
- CAS Key Laboratory of Mental Health, Institute of Psychology, 16 Lincui Rd, Beijing 100101, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiao-Fang Wang
- Pain Research Center and Department of Physiology, Zhongshan School of Medicine of Sun Yat-sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Jie-Zhen Mai
- Pain Research Center and Department of Physiology, Zhongshan School of Medicine of Sun Yat-sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Yong-Yong Li
- Pain Research Center and Department of Physiology, Zhongshan School of Medicine of Sun Yat-sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Ning Wu
- Beijing Key Laboratory of Neuropsychopharmacology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing 100850, China
| | - Cheng Zhang
- Beijing Key Laboratory of Neuropsychopharmacology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing 100850, China
| | - Jin Li
- Beijing Key Laboratory of Neuropsychopharmacology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing 100850, China
| | - Rui-Ping Pang
- Pain Research Center and Department of Physiology, Zhongshan School of Medicine of Sun Yat-sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China.
| | - Xian-Guo Liu
- Pain Research Center and Department of Physiology, Zhongshan School of Medicine of Sun Yat-sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China; Guangdong Provincial Key Laboratory of Brain Function and Disease, 74 Zhongshan Rd. 2, Guangzhou 510080, China.
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32
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Markman JD, Baron R, Gewandter JS. Why are there no drugs indicated for sciatica, the most common chronic neuropathic syndrome of all? Drug Discov Today 2018; 23:1904-1909. [PMID: 29894812 DOI: 10.1016/j.drudis.2018.06.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 05/16/2018] [Accepted: 06/05/2018] [Indexed: 10/14/2022]
Abstract
This review examines the stark contrast between the successes and failures of the clinical development of analgesics for different types of chronic low back pain (CLBP) syndrome over the past three decades. Multiple drugs with differing mechanisms of action have been developed for nonspecific axial-predominant low back syndromes and yet not a single therapy is indicated for any neuropathic low back pain syndrome (e.g., sciatica). Clinician findings have informed the entry criteria for neuropathic low back pain clinical trials, whereas entry criteria of axial CLBP trials have prioritized only patient reports of pain. This key difference could account for the lack of success in developing therapies for neuropathic low back pain in an era marked by successful development of analgesics for other types of CLBP as well as many chronic pain syndromes associated with nerve injury, such as post-herpetic neuralgia (PHN).
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Affiliation(s)
- John D Markman
- Department of Neurosurgery, Translational Pain Research Program, University of Rochester, 2180 South Clinton Avenue, Rochester, NY, USA.
| | - Ralf Baron
- Division of Neurological Pain Research and Therapy, Universitaetsklinikum Schleswig-Holstein, Campus Kiel, Haus 41, Arnold-Heller-Strasse 3, 24105 Kiel, Germany
| | - Jennifer S Gewandter
- Department of Anesthesiology and Perioperative Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY, USA
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Pregabalin induces conditioned place preference in the rat during the early, but not late, stage of neuropathic pain. Neurosci Lett 2018; 668:133-137. [PMID: 29355692 DOI: 10.1016/j.neulet.2018.01.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 01/13/2018] [Accepted: 01/15/2018] [Indexed: 11/24/2022]
Abstract
The present study aimed to examine the rewarding effects of pain relief during the early and late stages of neuropathic pain using a conditioned place preference (CPP) test. Animal models of neuropathic pain were prepared by spinal nerve ligation in male Sprague-Dawley rats. Intraperitoneal and intrathecal injections of pregabalin (300 mg/kg and 100 μg/10 μL, respectively) suppressed allodynia in the von Frey test both 2 weeks (early stage) and 4 weeks (late stage) after nerve injury. Intraperitoneal and intrathecal injections of pregabalin induced CPP during the early stage of neuropathic pain, suggesting that the CPP test serves as an objective and quantifiable behavioral assay to assess the emotional aspect of pain relief. In contrast with the early stage of neuropathic pain, intraperitoneal or intrathecal injection of pregabalin did not induce CPP during the late stage of neuropathic pain. The extinguishment of the rewarding effects of pregabalin during the late stage of neuropathic pain is likely due to dysfunction of the mesolimbic reward system, although the possibility that neuronal mechanisms other than dysfunction of the mesolimbic reward system are involved in the extinguishment of pregabalin-induced CPP cannot be excluded. We previously reported that not only the dopamine release in the nucleus accumbens induced by intrathecal pregabalin injection but also that induced by sucrose intake were extinguished during the late stage of neuropathic pain. These findings, combined with the results of this study, suggest that pain chronification leads to dysfunction of the mesolimbic reward system.
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Bulleyaconitine A preferably reduces tetrodotoxin-sensitive sodium current in uninjured dorsal root ganglion neurons of neuropathic rats probably via inhibition of protein kinase C. Pain 2017; 158:2169-2180. [DOI: 10.1097/j.pain.0000000000001018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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35
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Rosenthal P, Borsook D, Moulton EA. Oculofacial Pain: Corneal Nerve Damage Leading to Pain Beyond the Eye. Invest Ophthalmol Vis Sci 2017; 57:5285-5287. [PMID: 27723896 PMCID: PMC5063054 DOI: 10.1167/iovs.16-20557] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The cornea is supplied principally by the ophthalmic branch of the trigeminal nerve and is the most densely innervated organ in the human body. Under normal conditions, the corneal nerve terminals incorporate sensors that monitor the thickness and integrity of the tear film, which are essential for meaningful vision. A disrupted tear film or direct noxious stimulation of these corneal nerves can produce discomfort or pain limited to the affected surface. Damage to these nerves can sometimes lead to a chronic neuropathic condition, where pain persists months following the initial insult, long after the nerves appear to have healed in the cornea itself following treatment. Neuropathic pain appears to persist indefinitely in a few patients.
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Affiliation(s)
- Perry Rosenthal
- Boston EyePain Foundation, Chestnut Hill, Massachusetts, United States
| | - David Borsook
- Center for Pain and the Brain, Boston Children's Hospital, Massachusetts General Hospital, McLean Hospital, Harvard Medical School, Boston, Massachusetts, United States 3Department of Anesthesia, Critical Care and Pain Medicine, Boston Children's Hospital, Boston Massachusetts, United States
| | - Eric A Moulton
- Center for Pain and the Brain, Boston Children's Hospital, Massachusetts General Hospital, McLean Hospital, Harvard Medical School, Boston, Massachusetts, United States 3Department of Anesthesia, Critical Care and Pain Medicine, Boston Children's Hospital, Boston Massachusetts, United States
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Zhang S, Kartha S, Lee J, Winkelstein BA. Techniques for Multiscale Neuronal Regulation via Therapeutic Materials and Drug Design. ACS Biomater Sci Eng 2017; 3:2744-2760. [DOI: 10.1021/acsbiomaterials.7b00012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Sijia Zhang
- Department of Bioengineering, University of Pennsylvania, 210 S. 33rd Street, 240 Skirkanich
Hall, Philadelphia, Pennsylvania 19104, United States
| | - Sonia Kartha
- Department of Bioengineering, University of Pennsylvania, 210 S. 33rd Street, 240 Skirkanich
Hall, Philadelphia, Pennsylvania 19104, United States
| | - Jasmine Lee
- Department of Physics and Astronomy, University of Pennsylvania, 209 S. 33rd Street, David Rittenhouse Laboratory, Philadelphia, Pennsylvania 19104, United States
| | - Beth A. Winkelstein
- Department of Bioengineering, University of Pennsylvania, 210 S. 33rd Street, 240 Skirkanich
Hall, Philadelphia, Pennsylvania 19104, United States
- Department
of Neurosurgery, University of Pennsylvania, Stemmler Hall, 3450 Hamilton Walk, Philadelphia, Pennsylvania 19104, United States
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Ding YQ, Xie WZ, Qi JG. Regenerative peripheral neuropathic pain: novel pathological pain, new therapeutic dimension. Rev Neurosci 2017; 28:65-76. [PMID: 27664772 DOI: 10.1515/revneuro-2016-0014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 08/07/2016] [Indexed: 01/02/2023]
Abstract
AbstractAfter peripheral nerve damage, injured or stressed primary sensory neurons (PSNs) transmitting pathological pain (pathopain) sensitize central nervous system (CNS) neural circuits and determine behavioral phenotypes of peripheral neuropathic pain (PNP). Therefore, phenotypic profiling of pathopain-transmitting PSNs is vital for probing and discovering PNP conditions. Following peripheral nerve injuries (PNIs), PNP might be potentially transmitted by distinct classes of damaged or stressed PSNs, such as axotomized PSNs without regeneration (axotomy-non-regenerative neurons), axotomized PSNs with accurate regeneration (axotomy-regenerative neurons), and spared intact PSNs adjacent to axotomized neurons (axotomy-spared neurons). Both axotomy-non-regenerative neurons and axotomy-spared neurons have been definitely shown to participate in specific PNP transmission. However, whether axotomy-regenerative neurons could transmit PNP with unique features has remained unclear. Recent studies in rodent models of axonotmesis have clearly demonstrated that axotomy-regenerative neurons alone transmit persistent pathological pain with unique behavioral phenotypes. In this review, we exclusively review this novel category of PNP, reasonably term it ‘regenerative peripheral neuropathic pain’, and finally discuss its potential clinical significance as a new therapeutic dimension for PNIs beyond nerve regeneration.
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Todd AJ. Identifying functional populations among the interneurons in laminae I-III of the spinal dorsal horn. Mol Pain 2017; 13:1744806917693003. [PMID: 28326935 PMCID: PMC5315367 DOI: 10.1177/1744806917693003] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 12/16/2016] [Indexed: 12/15/2022] Open
Abstract
The spinal dorsal horn receives input from primary afferent axons, which terminate in a modality-specific fashion in different laminae. The incoming somatosensory information is processed through complex synaptic circuits involving excitatory and inhibitory interneurons, before being transmitted to the brain via projection neurons for conscious perception. The dorsal horn is important, firstly because changes in this region contribute to chronic pain states, and secondly because it contains potential targets for the development of new treatments for pain. However, at present, we have only a limited understanding of the neuronal circuitry within this region, and this is largely because of the difficulty in defining functional populations among the excitatory and inhibitory interneurons. The recent discovery of specific neurochemically defined interneuron populations, together with the development of molecular genetic techniques for altering neuronal function in vivo, are resulting in a dramatic improvement in our understanding of somatosensory processing at the spinal level.
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Affiliation(s)
- Andrew J Todd
- Institute of Neuroscience and Psychology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
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39
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Kato T, Ide S, Minami M. Pain relief induces dopamine release in the rat nucleus accumbens during the early but not late phase of neuropathic pain. Neurosci Lett 2016; 629:73-78. [DOI: 10.1016/j.neulet.2016.06.060] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 06/27/2016] [Accepted: 06/28/2016] [Indexed: 10/21/2022]
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40
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Bjurström MF, Nicol AL, Amid PK, Lee CH, Ferrante FM, Chen DC. Neurophysiological and Clinical Effects of Laparoscopic Retroperitoneal Triple Neurectomy in Patients with Refractory Postherniorrhaphy Neuropathic Inguinodynia. Pain Pract 2016; 17:447-459. [DOI: 10.1111/papr.12468] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 03/22/2016] [Accepted: 04/13/2016] [Indexed: 12/16/2022]
Affiliation(s)
- Martin F. Bjurström
- Department of Anesthesiology; University of California, Los Angeles (UCLA); Los Angeles California U.S.A
- Cousins Center for Psychoneuroimmunology; University of California, Los Angeles (UCLA); Los Angeles California U.S.A
| | - Andrea L. Nicol
- Department of Anesthesiology; University of Kansas; Kansas City Kansas U.S.A
| | - Parviz K. Amid
- Department of Surgery; Lichtenstein Amid Hernia Clinic at UCLA; Los Angeles California U.S.A
| | - Christine H. Lee
- Department of Anesthesiology; University of California, Los Angeles (UCLA); Los Angeles California U.S.A
| | - Francis M. Ferrante
- Department of Anesthesiology; University of California, Los Angeles (UCLA); Los Angeles California U.S.A
| | - David C. Chen
- Department of Surgery; Lichtenstein Amid Hernia Clinic at UCLA; Los Angeles California U.S.A
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Zhao P, Hill M, Liu S, Chen L, Bangalore L, Waxman SG, Tan AM. Dendritic spine remodeling following early and late Rac1 inhibition after spinal cord injury: evidence for a pain biomarker. J Neurophysiol 2016; 115:2893-910. [PMID: 26936986 DOI: 10.1152/jn.01057.2015] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 03/01/2016] [Indexed: 12/15/2022] Open
Abstract
Neuropathic pain is a significant complication following spinal cord injury (SCI) with few effective treatments. Drug development for neuropathic pain often fails because preclinical studies do not always translate well to clinical conditions. Identification of biological characteristics predictive of disease state or drug responsiveness could facilitate more effective clinical translation. Emerging evidence indicates a strong correlation between dendritic spine dysgenesis and neuropathic pain. Because dendritic spines are located on dorsal horn neurons within the spinal cord nociceptive system, dendritic spine remodeling provides a unique opportunity to understand sensory dysfunction after SCI. In this study, we provide support for the postulate that dendritic spine profiles can serve as biomarkers for neuropathic pain. We show that dendritic spine profiles after SCI change to a dysgenic state that is characteristic of neuropathic pain in a Rac1-dependent manner. Suppression of the dysgenic state through inhibition of Rac1 activity is accompanied by attenuation of neuropathic pain. Both dendritic spine dysgenesis and neuropathic pain return when inhibition of Rac1 activity is lifted. These findings suggest the utility of dendritic spines as structural biomarkers for neuropathic pain.
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Affiliation(s)
- Peng Zhao
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Myriam Hill
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Shujun Liu
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Lubin Chen
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Lakshmi Bangalore
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Andrew M Tan
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
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Wu SH, Huang SH, Lo YC, Chai CY, Lee SS, Chang KP, Lin SD, Lai CS, Yeh JL, Kwan AL. Autologous adipose-derived stem cells attenuate muscular atrophy and protect spinal cord ventral horn motor neurons in an animal model of burn injury. Cytotherapy 2016; 17:1066-75. [PMID: 26139546 DOI: 10.1016/j.jcyt.2015.03.687] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/19/2015] [Accepted: 03/20/2015] [Indexed: 11/27/2022]
Abstract
BACKGROUND AIMS Burn injuries might increase muscle mass loss, but the mechanisms are still unclear. In this study, we demonstrated that burn injury induced spinal cord ventral horn motor neuron (VHMN) apoptosis and subsequently caused muscle atrophy and revealed the potential protection of autologous adipose-derived stem cells (ASCs) transplantation on spinal cord VHMNs and muscle against burn injury. METHODS Third-degree hind-paw burns were established by contact with a 75°C metal surface for 10 seconds. Adipose tissues were harvested from the groin fat pad, expanded in culture and labeled with chloromethyl-benzamido/1,1'-dioctadecyl-3,3,3',3'- tetramethyl indocarbocyanine perchlorate. The ASCs were transplanted into the injured hind paw at 4 weeks after burn injury. The lumbar spinal cord, sciatic nerve, gastrocnemius muscle and hind-paw skin were processed for immunofluorescent staining at 4 weeks after transplantation, including terminal deoxynucleotidyl transferase (TUNEL) assay, caspase-3, caspase-9, CD 90 and S100, and the gastrocnemius muscle was evaluated through the use of hematoxylin and eosin staining. RESULTS Caspase-3-positive, caspase-9-positive and TUNEL-positive cells were significantly increased in the corresponding dermatome spinal cord VHMNs after burn injury. Moreover, the decrease of Schwann cells in sciatic nerve and the increase of denervation atrophy in gastrocnemius muscle were observed. Furthermore, ASCs transplantation significantly attenuated apoptotic death of VHMNs and the area of muscle denervation atrophy in the gastrocnemius muscle fibers. CONCLUSIONS The animal model of third-degree burns in the hind paw showed significant apoptosis in the corresponding spinal cord VHMNs, which suggests that neuroprotection might be the potentially therapeutic target in burn-induced muscle atrophy. ASCs have potential neuroprotection against burn injuries through its anti-apoptotic effects.
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Affiliation(s)
- Sheng-Hua Wu
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Anesthesia, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Shu-Hung Huang
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yi-Ching Lo
- Department and Graduate Institute of Pharmacology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
| | - Chee-Yin Chai
- Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Su-Shin Lee
- Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Kao-Ping Chang
- Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Sin-Daw Lin
- Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chung-Sheng Lai
- Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Jwu-Lai Yeh
- Department and Graduate Institute of Pharmacology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Aij-Lie Kwan
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Division of Neurosurgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
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Van Boxem K, de Meij N, Patijn J, Wilmink J, van Kleef M, Van Zundert J, Kessels A. Predictive Factors for Successful Outcome of Pulsed Radiofrequency Treatment in Patients with Intractable Lumbosacral Radicular Pain. PAIN MEDICINE 2016; 17:1233-1240. [PMID: 26791777 DOI: 10.1093/pm/pnv052] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND In a previous prospective study on pulsed radiofrequency (PRF) treatment adjacent to the lumbar dorsal root ganglion (DRG) for patients with chronic lumbosacral radicular pain, we reported success in 55.4% of the patients at 6 months. Identification of predictors for success after PRF may improve outcome. We assessed the predictors of PRF in patients with chronic intractable lumbosacral radicular pain. METHODS Patients with monosegmental chronic lumbosacral radicular pain of L5 or S1 first received a selective nerve root block at the corresponding level. Independent of the result of this block a PRF treatment at the same level was performed. At 6 weeks, 3 months, and 6 months after the procedure the outcome was evaluated. RESULTS A positive diagnostic nerve root block and age ≥ 55 were predictive factors for successful outcome at 6 months, while disability was a negative predictor.The use of failed back surgery syndrome, gender, duration of pain, Numerical Rating Scale, level and side of treatment, DN4, and RAND-36 as predictors for success was not supported. CONCLUSIONS Successful outcome after PRF adjacent to the DRG, in patients with intractable chronic lumbosacral radicular pain, is more likely in patients ≥ 55 years, with limited disability and after a positive diagnostic nerve root block. A combination of all these factors creates a fair predictive value (AUC: 0.73).
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Affiliation(s)
- Koen Van Boxem
- Departments of *Anesthesiology and Pain Management, Department of Anesthesiology, Critical Care and Multidisciplinary Pain Center, Sint-Jozefkliniek, Bornem & Willebroek, Belgium;
| | | | - Jacob Patijn
- Departments of *Anesthesiology and Pain Management
| | | | - Maarten van Kleef
- Departments of *Anesthesiology and Pain Management, Department of Anesthesiology and Pain Management, VUMC Amsterdam, The Netherlands
| | - Jan Van Zundert
- Departments of *Anesthesiology and Pain Management, Department of Anesthesiology, Critical Care and Multidisciplinary Pain Center, ZOL, Genk, Belgium
| | - Alfons Kessels
- Clinical Epidemiology and Medical Technology Assessment, Maastricht University Medical Centre, The Netherlands
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Neuropathic Pain: Sensory Nerve Injury or Motor Nerve Injury? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 904:59-75. [DOI: 10.1007/978-94-017-7537-3_5] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Shehab S, Anwer M, Galani D, Abdulkarim A, Al-Nuaimi K, Al-Baloushi A, Tariq S, Nagelkerke N, Ljubisavljevic M. Anatomical evidence that the uninjured adjacent L4 nerve plays a significant role in the development of peripheral neuropathic pain after L5 spinal nerve ligation in rats. J Comp Neurol 2015; 523:1731-47. [DOI: 10.1002/cne.23750] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 01/15/2015] [Accepted: 01/18/2015] [Indexed: 12/19/2022]
Affiliation(s)
- Safa Shehab
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Mehwish Anwer
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Divya Galani
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Afaf Abdulkarim
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Khuloud Al-Nuaimi
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Abdullah Al-Baloushi
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Saeed Tariq
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Nico Nagelkerke
- Department of Community Medicine, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Milos Ljubisavljevic
- Department of Physiology, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
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Needle-embedding therapy for fifty cases of post-herpetic neuralgia. WORLD JOURNAL OF ACUPUNCTURE-MOXIBUSTION 2015. [DOI: 10.1016/s1003-5257(15)30014-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Xie W, Strong JA, Zhang JM. Local knockdown of the NaV1.6 sodium channel reduces pain behaviors, sensory neuron excitability, and sympathetic sprouting in rat models of neuropathic pain. Neuroscience 2015; 291:317-30. [PMID: 25686526 DOI: 10.1016/j.neuroscience.2015.02.010] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 01/21/2015] [Accepted: 02/05/2015] [Indexed: 11/15/2022]
Abstract
In the spinal nerve ligation (SNL) model of neuropathic pain, as in other pain models, abnormal spontaneous activity of myelinated sensory neurons occurs early and is essential for establishing pain behaviors and other pathologies. Sympathetic sprouting into the dorsal root ganglion (DRG) is observed after SNL, and sympathectomy reduces pain behavior. Sprouting and spontaneous activity may be mutually reinforcing: blocking neuronal activity reduces sympathetic sprouting, and sympathetic spouts functionally increase spontaneous activity in vitro. However, most studies in this field have used nonspecific methods to block spontaneous activity, methods that also block evoked and normal activity. In this study, we injected small inhibitory (si) RNA directed against the NaV1.6 sodium channel isoform into the DRG before SNL. This isoform can mediate high-frequency repetitive firing, like that seen in spontaneously active neurons. Local knockdown of NaV1.6 markedly reduced mechanical pain behaviors induced by SNL, reduced sympathetic sprouting into the ligated sensory ganglion, and blocked abnormal spontaneous activity and other measures of hyperexcitability in myelinated neurons in the ligated sensory ganglion. Immunohistochemical experiments showed that sympathetic sprouting preferentially targeted NaV1.6-positive neurons. Under these experimental conditions, NaV1.6 knockdown did not prevent or strongly alter single evoked action potentials, unlike previous less specific methods used to block spontaneous activity. NaV1.6 knockdown also reduced pain behaviors in another pain model, chronic constriction of the sciatic nerve, provided the model was modified so that the lesion site was relatively close to the siRNA-injected lumbar DRGs. The results highlight the relative importance of abnormal spontaneous activity in establishing both pain behaviors and sympathetic sprouting, and suggest that the NaV1.6 isoform may have value as a therapeutic target.
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Affiliation(s)
- W Xie
- Pain Research Center, Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0531, USA.
| | - J A Strong
- Pain Research Center, Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0531, USA.
| | - J-M Zhang
- Pain Research Center, Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0531, USA.
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Zang Y, Chen SX, Liao GJ, Zhu HQ, Wei XH, Cui Y, Na XD, Pang RP, Xin WJ, Zhou LJ, Liu XG. Calpain-2 contributes to neuropathic pain following motor nerve injury via up-regulating interleukin-6 in DRG neurons. Brain Behav Immun 2015; 44:37-47. [PMID: 25150005 DOI: 10.1016/j.bbi.2014.08.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 07/25/2014] [Accepted: 08/12/2014] [Indexed: 01/09/2023] Open
Abstract
Motor nerve injury by L5 ventral root transection (L5-VRT) initiates interleukin-6 (IL-6) up-regulation in primary afferent system contributing to neuropathic pain. However, the early upstream regulatory mechanisms of IL-6 after L5-VRT are still unknown. Here, we monitored both the activity of calpain, a calcium-dependent protease suggested as one of the earliest mediators for cytokine regulation, and the expression of IL-6 in bilateral L4-L6 dorsal root ganglias (DRGs) soon after L5-VRT. We found that the protein level of calpain-2 in DRGs, but not calpain-1 was increased transiently in the first 10 min(-1)h ipsilaterally and 20 min(-1)h contralaterally after L5-VRT, long before mechanical allodynia was initiated (5-15 h ipsilaterally and 15 h(-1)d contralaterally). The early activation of calpain evaluated by the generation of spectrin breakdown products (SBDP) correlated well with IL-6 up-regulation in bilateral DRGs. Double immunofluorescence staining revealed that almost all the calpain-2 positive neurons expressed IL-6, indicating an association between calpain-2 and IL-6. Inhibition of calpain by pre-treatment with MDL28170 (25mg/kg, i.p.) attenuated the rat mechanical allodynia and prevented the early up-regulation of IL-6 following L5-VRT. Addition of exogenous calpain-2 onto the surface of left L5 DRG triggered a temporal allodynia and increased IL-6 in bilateral DRGs simultaneously. Taken together, the early increase of calpain-2 in L5-VRT rats might be responsible for the induction of allodynia via up-regulating IL-6 in DRG neurons.
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Affiliation(s)
- Ying Zang
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China.
| | - Shao-Xia Chen
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Guang-Jie Liao
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China; Department of Pathology, The Red Cross Hospital of Yulin, 1 Jinwang Rd., Yulin 537000, China
| | - He-Quan Zhu
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Xu-Hong Wei
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Yu Cui
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Xiao-Dong Na
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China; Department of Pathophysiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Rui-Ping Pang
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Wen-Jun Xin
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Li-Jun Zhou
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Xian-Guo Liu
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
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Third-degree hindpaw burn injury induced apoptosis of lumbar spinal cord ventral horn motor neurons and sciatic nerve and muscle atrophy in rats. BIOMED RESEARCH INTERNATIONAL 2015; 2015:372819. [PMID: 25695065 PMCID: PMC4324890 DOI: 10.1155/2015/372819] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Accepted: 11/25/2014] [Indexed: 12/17/2022]
Abstract
Background. Severe burns result in hypercatabolic state and concomitant muscle atrophy that persists for several months, thereby limiting patient recovery. However, the effects of burns on the corresponding spinal dermatome remain unknown. This study aimed to investigate whether burns induce apoptosis of spinal cord ventral horn motor neurons (VHMNs) and consequently cause skeletal muscle wasting. Methods. Third-degree hindpaw burn injury with 1% total body surface area (TBSA) rats were euthanized 4 and 8 weeks after burn injury. The apoptosis profiles in the ventral horns of the lumbar spinal cords, sciatic nerves, and gastrocnemius muscles were examined. The Schwann cells in the sciatic nerve were marked with S100. The gastrocnemius muscles were harvested to measure the denervation atrophy. Result. The VHMNs apoptosis in the spinal cord was observed after inducing third-degree burns in the hindpaw. The S100 and TUNEL double-positive cells in the sciatic nerve increased significantly after the burn injury. Gastrocnemius muscle apoptosis and denervation atrophy area increased significantly after the burn injury. Conclusion. Local hindpaw burn induces apoptosis in VHMNs and Schwann cells in sciatic nerve, which causes corresponding gastrocnemius muscle denervation atrophy. Our results provided an animal model to evaluate burn-induced muscle wasting, and elucidate the underlying mechanisms.
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Nam JS, Cheong YS, Karm MH, Ahn HS, Sim JH, Kim JS, Choi SS, Leem JG. Effects of nefopam on streptozotocin-induced diabetic neuropathic pain in rats. Korean J Pain 2014; 27:326-33. [PMID: 25317281 PMCID: PMC4196497 DOI: 10.3344/kjp.2014.27.4.326] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 09/19/2014] [Accepted: 09/25/2014] [Indexed: 11/22/2022] Open
Abstract
Background Nefopam is a centrally acting non-opioid analgesic agent. Its analgesic properties may be related to the inhibitions of monoamine reuptake and the N-methyl-D-aspartate (NMDA) receptor. The antinociceptive effect of nefopam has been shown in animal models of acute and chronic pain and in humans. However, the effect of nefopam on diabetic neuropathic pain is unclear. Therefore, we investigated the preventive effect of nefopam on diabetic neuropathic pain induced by streptozotocin (STZ) in rats. Methods Pretreatment with nefopam (30 mg/kg) was performed intraperitoneally 30 min prior to an intraperitoneal injection of STZ (60 mg/kg). Mechanical and cold allodynia were tested before, and 1 to 4 weeks after drug administration. Thermal hyperalgesia was also investigated. In addition, the transient receptor potential ankyrin 1 (TRPA1) and TRP melastatin 8 (TRPM8) expression levels in the dorsal root ganglion (DRG) were evaluated. Results Pretreatment with nefopam significantly inhibited STZ-induced mechanical and cold allodynia, but not thermal hyperalgesia. The STZ injection increased TRPM8, but not TRPA1, expression levels in DRG neurons. Pretreatment with nefopam decreased STZ-induced TRPM8 expression levels in the DRG. Conclusions These results demonstrate that a nefopam pretreatment has strong antiallodynic effects on STZ-induced diabetic rats, which may be associated with TRPM8 located in the DRG.
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Affiliation(s)
- Jae Sik Nam
- Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Yu Seon Cheong
- Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Myong Hwan Karm
- Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Ho Soo Ahn
- Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Ji Hoon Sim
- Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Jin Sun Kim
- Department of Anesthesiology and Pain Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea
| | - Seong Soo Choi
- Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Jeong Gil Leem
- Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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