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Sample records for treat neuropathic pain

  1. Spinal interleukin-10 therapy to treat peripheral neuropathic pain.

    Science.gov (United States)

    Milligan, Erin D; Penzkover, Kathryn R; Soderquist, Ryan G; Mahoney, Melissa J

    2012-01-01

      Current research indicates that chronic peripheral neuropathic pain includes a role for glia and the actions of proinflammatory factors. This review briefly discusses the glial and cytokine responses that occur following peripheral nerve damage in support of utilizing anti-inflammatory cytokine interleukin-10 (IL-10) therapy to suppress chronic peripheral neuropathic pain. SPINAL NONVIRAL INTERLEUKIN-10 GENE THERAPY:  IL-10 is one of the most powerful endogenous counter-regulators of proinflammatory cytokine function that acts in the nervous system. Subarachnoid (intrathecal) spinal injection of the gene encoding IL-10 delivered by nonviral vectors has several advantages over virally mediated gene transfer methods and leads to profound pain relief in several animal models. NONVIRAL GENE DELIVERY:  Lastly, data are reviewed that nonviral deoxyribonucleic acid (DNA) encapsulated by a biologically safe copolymer, poly(lactic-co-glycolic) acid (PLGA), thought to protect DNA, leads to significantly improved therapeutic gene transfer in animal models, which additionally and significantly extends pain relief.   The impact of these early studies exploring anti-inflammatory genes emphasizes the exceptional therapeutic potential of new biocompatible intrathecal nonviral gene delivery approaches such as PLGA microparticles. Ultimately, ongoing expression of therapeutic genes is a viable option to treat chronic neuropathic pain in the clinic. © 2012 International Neuromodulation Society.

  2. Neuropathic pain

    Directory of Open Access Journals (Sweden)

    Giuseppe Re

    2009-02-01

    Full Text Available Neuropathic pain is the expression of a dysfunction or primary lesion of a nerve in the peripheral or central nervous system, or both, rather than the biological signal transmitted by the nerve following peripheral nociceptor activation. It represents about 20% of all painful syndromes, with an estimated prevalence of 1.5%, however is actual incidence is hard to pinpoint due to the difficulties encountered in distinguishing it from chronic pain, of which it represents a significant percentage, on account of the not infrequent concurrence of conditions. It is crucial to recognise the variety of symptoms with which it can present: these can be negative and positive and, in turn, motor, sensitive and autonomic. In public health terms, it is important to emphasise that the diagnosis of neuropathic pain does not in most cases require sophisticated procedures and does not therefore weigh on health expenditure. In clinical practice, a validated scale (the LANSS is mentioned is useful for identifying patients presenting neuropathic pain symptoms. Therapy is based on three categories of medication: tricyclic antidepressants, anti-epileptics and opioids at high doses: neuropathic pain has a bad reputation for often resisting common therapeutic approaches and responding less well that nociceptor pain to monotherapy. Therapeutic strategies are all the more adequate the more they are based on symptoms and therefore on the pain generation mechanisms, although the recommendations are dictated more by expert opinions that double-blind randomised trials.

  3. Neuropathic Pain and Psychological Morbidity in Patients with Treated Leprosy: A Cross-Sectional Prevalence Study in Mumbai

    Science.gov (United States)

    Lasry-Levy, Estrella; Hietaharju, Aki; Pai, Vivek; Ganapati, Ramaswamy; Rice, Andrew S. C.; Haanpää, Maija; Lockwood, Diana N. J.

    2011-01-01

    Background Neuropathic pain has been little studied in leprosy. We assessed the prevalence and clinical characteristics of neuropathic pain and the validity of the Douleur Neuropathique 4 questionnaire as a screening tool for neuropathic pain in patients with treated leprosy. The association of neuropathic pain with psychological morbidity was also evaluated. Methodology/Principal Findings Adult patients who had completed multi-drug therapy for leprosy were recruited from several Bombay Leprosy Project clinics. Clinical neurological examination, assessment of leprosy affected skin and nerves and pain evaluation were performed for all patients. Patients completed the Douleur Neuropathique 4 and the 12-item General Health Questionnaire to identify neuropathic pain and psychological morbidity. Conclusions/Significance One hundred and one patients were recruited, and 22 (21.8%) had neuropathic pain. The main sensory symptoms were numbness (86.4%), tingling (68.2%), hypoesthesia to touch (81.2%) and pinprick (72.7%). Neuropathic pain was associated with nerve enlargement and tenderness, painful skin lesions and with psychological morbidity. The Douleur Neuropathique 4 had a sensitivity of 100% and specificity of 92% in diagnosing neuropathic pain. The Douleur Neuropathique 4 is a simple tool for the screening of neuropathic pain in leprosy patients. Psychological morbidity was detected in 15% of the patients and 41% of the patients with neuropathic pain had psychological morbidity. PMID:21408111

  4. Managing neuropathic pain in dogs

    Directory of Open Access Journals (Sweden)

    Sarah A Moore

    2016-02-01

    Full Text Available Disorders of the somatosensory system such as neuropathic pain are common in people with chronic neurologic and musculoskeletal diseases, yet these conditions remain an underappreciated morbidity in our veterinary patients. This is likely because assessment of neuropathic pain in people relies heavily on self-reporting, something our veterinary patients are not able to do. The development of neuropathic pain is a complex phenomenon, and concepts related to it are frequently not addressed in the standard veterinary medical curriculum such that veterinarians may not recognize this as a potential problem in patients. The goals of this review are to discuss basic concepts in the pathophysiology of neuropathic pain, provide definitions for common clinical terms used in association with the condition, and discuss available medical treatment options for dogs with neuropathic pain. The development of neuropathic pain involves key mechanisms such as ectopic afferent nerve activity, peripheral sensitization, central sensitization, impaired inhibitory modulation, and activation of microglia. Treatments aimed at reducing neuropathic pain are targeted at one or more of these mechanisms. Several drugs are commonly used in the veterinary clinical setting to treat neuropathic pain. These include gabapentin, pregabalin, amantadine, and amitriptyline. Proposed mechanisms of action for each drug, and known pharmacokinetic profiles in dogs are discussed. Strong evidence exists in the human literature for the utility of most of these treatments, but clinical veterinary-specific literature is currently limited. Future studies should focus on objective methods to document neuropathic pain and monitor response to therapy in our veterinary patients.

  5. Oxcarbazepine for neuropathic pain.

    Science.gov (United States)

    Zhou, Muke; Chen, Ning; He, Li; Yang, Mi; Zhu, Cairong; Wu, Fengbo

    2017-12-02

    painful DPN, compared to the baseline, the proportion of participants who reported at least a 50% or 30% reduction of pain scores after 16 weeks of treatment in the oxcarbazepine group versus the placebo group were: at least 50% reduction: 34.8% with oxcarbazepine versus 18.2% with placebo (risk ratio (RR) 1.91, 95% confidence interval (CI) 1.08 to 3.39, number of people needed to treat for an additional beneficial outcome (NNTB) 6, 95% CI 3 to 41); and at least 30% reduction: 44.9% with oxcarbazepine versus 28.6% with placebo (RR 1.57, 95% CI 1.01 to 2.44; NNTB 6, 95% CI 3 to 114; n = 146). Both results were based on data from a single trial, since two trials that found little or no benefit did not provide data that could be included in a meta-analysis. Although these trials were well designed, incomplete outcome data and possible unblinding of participants due to obvious adverse effects placed the results at a high risk of bias. There was also serious imprecision and a high risk of publication bias. The radiculopathy trial reported no benefit for the outcome 'at least 50% pain relief' from oxcarbazepine. In mixed neuropathies, 19.3% of people receiving oxcarbazepine versus 4.8% receiving placebo had at least 50% pain relief. These small trials had low event rates and provided, at best, low-quality evidence for any outcome. The proportion of people with 'improved' or 'very much improved' pain was 45.9% with oxcarbazepine versus 30.1% with placebo in DPN (RR 1.46, 95% CI 1.13 to 1.88; n = 493; 2 trials; very-low-quality evidence) and 23.9% with oxcarbazepine versus 14.9% with placebo in radiculopathy (RR 1.61, 95% CI 0.81 to 3.20; n = 145).We found no trials in other types of neuropathic pain such as trigeminal neuralgia.Trial reports stated that most adverse effects were mild to moderate in severity. Based on moderate-quality evidence from the three DPN trials, serious adverse effects occurred in 8.3% with oxcarbazepine and 2.5% with placebo (RR 3.65, 95% CI 1.45 to 9

  6. Melanocortins and Neuropathic Pain

    NARCIS (Netherlands)

    Vrinten, Dorien Henriëtte

    2003-01-01

    Neuropathic pain (pain initiated by a lesion or dysfunction of the nervous system) is characterised by symptoms such as allodynia (pain due to a stimulus that does not normally provoke pain) and hyperalgesia (an increased response to a stimulus that is normally painful). It constitutes a major

  7. Neuropathic pain in primary care

    African Journals Online (AJOL)

    The operative difference is that neuropathic pain represents a delayed, ongoing response to damage that is no longer acute ... Postsurgical pain (including post- mastectomy and phantom limb pain). Spinal cord injury pain ... Management of neuropathic pain. Neuropathic pain tends to exhibit a relatively poor response.

  8. A Mangifera indica L. extract could be used to treat neuropathic pain and implication of mangiferin.

    Science.gov (United States)

    Garrido-Suárez, Bárbara B; Garrido, Gabino; Delgado, Rene; Bosch, Fe; del C Rabí, María

    2010-12-09

    It has been accepted that neuroinflammation, oxidative stress and glial activation are involved in the central sensitization underlying neuropathic pain. Vimang is an aqueous extract of Mangifera indica L. traditionally used in Cuba for its analgesic, anti-inflammatory, antioxidant and immunomodulatory properties. Several formulations are available, and also for mangiferin, its major component. Preclinical studies demonstrated that these products prevented tumor necrosis factor α -induced IκB degradation and the binding of nuclear factor κB to DNA, which induces the transcription of genes implicated in the expression of some mediators and enzymes involved in inflammation, pain, oxidative stress and synaptic plasticity. In this paper we propose its potential utility in the neuropathic pain treatment. This hypothesis is supported in the cumulus of preclinical and clinical evidence around the extract and mangiferin, its major component, and speculates about the possible mechanism of action according to recent advances in the physiopathology of neuropathic pain.

  9. A Mangifera indica L. Extract Could Be Used to Treat Neuropathic Pain and Implication of Mangiferin

    Directory of Open Access Journals (Sweden)

    María del C. Rabí

    2010-12-01

    Full Text Available It has been accepted that neuroinflammation, oxidative stress and glial activation are involved in the central sensitization underlying neuropathic pain. Vimang is an aqueous extract of Mangifera indica L. traditionally used in Cuba for its analgesic, anti-inflammatory, antioxidant and immunomodulatory properties. Several formulations are available, and also for mangiferin, its major component. Preclinical studies demonstrated that these products prevented tumor necrosis factor α -induced IκB degradation and the binding of nuclear factor κB to DNA, which induces the transcription of genes implicated in the expression of some mediators and enzymes involved in inflammation, pain, oxidative stress and synaptic plasticity. In this paper we propose its potential utility in the neuropathic pain treatment. This hypothesis is supported in the cumulus of preclinical and clinical evidence around the extract and mangiferin, its major component, and speculates about the possible mechanism of action according to recent advances in the physiopathology of neuropathic pain.

  10. Interventional therapy for neuropathic pain

    Directory of Open Access Journals (Sweden)

    YANG Yang

    2013-10-01

    Full Text Available Neuropathic pain (NP is a common clinical refractory pain for which there are limited methods to treat. In this article, based on typical diseases, such as postherpetic neuralgia (PHN, trigeminal neuralgia, complex regional pain syndrome (CRPS, lower back pain with radiculopathy and failed back surgery syndrome (FBSS, phantom pain, the general treatment principle and method for NP are expatiated. Interventional methods for NP, including intraspinal block, radiofrequeney rhizotomy of trigeminal neuralgia, selective nerve root block, spinal cord stimulation (SCS and motor cortex stimulation (MCS are introduced, especially their indications, complications and matters needing attention.

  11. [Management of neuropathic pain].

    Science.gov (United States)

    Lozeron, P; Kubis, N

    2015-07-01

    Neuropathic pain is often underestimated and not adequately treated. The DN4 scale is very useful for its identification since it will benefit from pharmacological and non-pharmacological specific alternative care. The pathophysiological mechanisms involve the hyperexcitability of nociceptive pathways or decreased inhibitory descending controls that will be the target of pharmacological treatments. Frontline molecules are antidepressants (tricyclics and mixed serotonin and norepinephrine reuptake inhibitors) and antiepileptics (α2δ calcium channel inhibitors). However, these drugs will only have a partial efficacy on pain. The therapeutic strategy is based on reasonable goals, starting with a monotherapy adapted to the patient's symptoms and comorbidities and increased step by step. Patient compliance to contract is essential and requires clear and complete information. The impact on profession, social and family integration should rapidly be taken into account. In case of inefficiency, a change of the first-line treatment or an association could be considered. Some indications justify a specific therapy. Patients with resistant chronic pain should be sent to a specialized centre. New drugs are being studied and non-pharmacological support must be evaluated. Copyright © 2015 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  12. Pharmacologic management of chronic neuropathic pain

    Science.gov (United States)

    Mu, Alex; Weinberg, Erica; Moulin, Dwight E.; Clarke, Hance

    2017-01-01

    Abstract Objective To provide family physicians with a practical clinical summary of the Canadian Pain Society (CPS) revised consensus statement on the pharmacologic management of neuropathic pain. Quality of evidence A multidisciplinary interest group within the CPS conducted a systematic review of the literature on the current treatments of neuropathic pain in drafting the revised consensus statement. Main message Gabapentinoids, tricyclic antidepressants, and serotonin-norepinephrine reuptake inhibitors are the first-line agents for treating neuropathic pain. Tramadol and other opioids are recommended as second-line agents, while cannabinoids are newly recommended as third-line agents. Other anticonvulsants, methadone, tapentadol, topical lidocaine, and botulinum toxin are recommended as fourth-line agents. Conclusion Many pharmacologic analgesics exist for the treatment of neuropathic pain. Through evidence-based recommendations, the CPS revised consensus statement helps guide family physicians in the management of patients with neuropathic pain. PMID:29138154

  13. Analgesic Microneedle Patch for Neuropathic Pain Therapy.

    Science.gov (United States)

    Xie, Xi; Pascual, Conrado; Lieu, Christopher; Oh, Seajin; Wang, Ji; Zou, Bende; Xie, Julian; Li, Zhaohui; Xie, James; Yeomans, David C; Wu, Mei X; Xie, Xinmin Simon

    2017-01-24

    Neuropathic pain caused by nerve injury is debilitating and difficult to treat. Current systemic pharmacological therapeutics for neuropathic pain produce limited pain relief and have undesirable side effects, while current local anesthetics tend to nonspecifically block both sensory and motor functions. Calcitonin gene related peptide (CGRP), a neuropeptide released from sensory nerve endings, appears to play a significant role in chronic neuropathic pain. In this study, an analgesic microneedle (AMN) patch was developed using dissolvable microneedles to transdermally deliver selective CGRP antagonist peptide in a painless manner for the treatment of localized neuropathic pain. Local analgesic effects were evaluated in rats by testing behavioral pain sensitivity in response to thermal and mechanical stimuli using neuropathic pain models such as spared-nerve injury and diabetic neuropathy pain, as well as neurogenic inflammatory pain model induced by ultraviolet B (UVB) radiation. Unlike several conventional therapies, the AMN patches produced effective analgesia on neuropathic pain without disturbing the normal nociception and motor function of the rat, resulting from the high specificity of the delivered peptide against CGRP receptors. The AMN patches did not cause skin irritation or systemic side effects. These results demonstrate that dissolvable microneedle patches delivering CGRP antagonist peptide provide an effective, safe, and simple approach to mitigate neuropathic pain with significant advantages over current treatments.

  14. A randomized controlled trial of botulinum toxin A for treating neuropathic pain in patients with spinal cord injury.

    Science.gov (United States)

    Li, Gang; Lv, Chang-An; Tian, Li; Jin, Lian-Jin; Sun, Ping; Zhao, Wei

    2017-05-01

    To assess the effect of botulinum toxin A (BTA) for treating neuropathic pain in patients with spinal cord injury (SCI). A total of 44 patients with SCI with neuropathic pain were randomly divided into the intervention group and the placebo group, each group 21 patients. The subjects in the intervention group received BTA (200 U subcutaneous injection, once daily) at the painful area, whereas those in the placebo group were administered a saline placebo. This study was conducted from December 2014 to November 2016. The primary outcome was measured using the visual analog scale (VAS). The secondary outcomes were measured using the short-form McGill Pain Questionnaire (SF-MPQ), and World Health Organization quality of life (WHOQOL-BREF) questionnaire. All outcome measurements were performed before and after 4 and 8 weeks of intervention. Forty-one participants completed the study. The intervention with BTA showed greater efficacy than placebo in decreasing the VAS score after week 4 and week 8 of treatment. Significant differences in the SF-MPQ and WHOQOL-BREF were also found between the 2 groups. The results of this study demonstrated that BTA might decrease intractable neuropathic pain for patients with SCI.

  15. Poly(ADP-ribose polymerase inhibition reveals a potential mechanism to promote neuroprotection and treat neuropathic pain

    Directory of Open Access Journals (Sweden)

    Prashanth Komirishetty

    2016-01-01

    Full Text Available Neuropathic pain is triggered by the lesions to peripheral nerves which alter their structure and function. Neuroprotective approaches that limit the pathological changes and improve the behavioral outcome have been well explained in different experimental models of neuropathy but translation of such strategies to clinics has been disappointing. Experimental evidences revealed the role of free radicals, especially peroxynitrite after the nerve injury. They provoke oxidative DNA damage and consequent over-activation of the poly(ADP-ribose polymerase (PARP upregulates pro-inflammatory pathways, causing bioenergetic crisis and neuronal death. Along with these changes, it causes mitochondrial dysfunction leading to neuronal apoptosis. In related preclinical studies agents that neutralize the free radicals and pharmacological inhibitors of PARP have shown benefits in treating experimental neuropathy. This article reviews the involvement of PARP over-activation in trauma induced neuropathy and therapeutic significance of PARP inhibitors in the experimental neuropathy and neuropathic pain.

  16. Poly(ADP-ribose) polymerase inhibition reveals a potential mechanism to promote neuroprotection and treat neuropathic pain.

    Science.gov (United States)

    Komirishetty, Prashanth; Areti, Aparna; Gogoi, Ranadeep; Sistla, Ramakrishna; Kumar, Ashutosh

    2016-10-01

    Neuropathic pain is triggered by the lesions to peripheral nerves which alter their structure and function. Neuroprotective approaches that limit the pathological changes and improve the behavioral outcome have been well explained in different experimental models of neuropathy but translation of such strategies to clinics has been disappointing. Experimental evidences revealed the role of free radicals, especially peroxynitrite after the nerve injury. They provoke oxidative DNA damage and consequent over-activation of the poly(ADP-ribose) polymerase (PARP) upregulates pro-inflammatory pathways, causing bioenergetic crisis and neuronal death. Along with these changes, it causes mitochondrial dysfunction leading to neuronal apoptosis. In related preclinical studies agents that neutralize the free radicals and pharmacological inhibitors of PARP have shown benefits in treating experimental neuropathy. This article reviews the involvement of PARP over-activation in trauma induced neuropathy and therapeutic significance of PARP inhibitors in the experimental neuropathy and neuropathic pain.

  17. Reduction of painful area as new possible therapeutic target in post-herpetic neuropathic pain treated with 5% lidocaine medicated plaster: a case series

    Directory of Open Access Journals (Sweden)

    Casale R

    2014-06-01

    Full Text Available Roberto Casale,1,2 Maria Di Matteo,3,7 Cristina E Minella,4,7 Guido Fanelli,5,7 Massimo Allegri4,6,71Department of Clinical Neurophysiology and Pain Rehabilitation Unit, Foundation Salvatore Maugeri, IRCCS, Pavia, 2EFIC Montescano School, Montescano, 3Anesthesia and Intensive Care I, 4Pain Therapy Service, Fondazione IRCCS Policlinico San Matteo, Pavia, 5Department of Anesthesia, Intensive Care and Pain Therapy, Azienda Ospedaliera Universitaria Parma, University of Parma, Parma, 6Department of Clinical, Surgical, Diagnostic and Pediatric Science, University of Pavia, Pavia, 7Study In Multidisciplinary Pain Research Group, Parma, ItalyAbstract: Post-herpetic neuralgia (PHN is neuropathic pain persisting after an acute episode of herpes zoster, and is associated with severe pain and sensory abnormalities that adversely affect the patient's quality of life and increase health care costs. Up to 83% of patients with PHN describe localized neuropathic pain, defined as “a type of neuropathic pain characterized by consistent and circumscribed area(s of maximum pain”. Topical treatments have been suggested as a first-line treatment for localized neuropathic pain. Use of 5% lidocaine medicated plaster could reduce abnormal nervous peripheral discharge and via the plaster could have a “protective” function in the affected area. It has been suggested that use of this plaster could reduce pain as well as the size of the painful area. To evaluate this possible outcome, we retrospectively reviewed eight patients with PHN, treated using 5% lidocaine medicated plaster. During a follow-up period of 3 months, we observed good pain relief, which was associated with a 46% reduction in size of the painful area after one month (from 236.38±140.34 cm2 to 128.80±95.7 cm2 and a 66% reduction after 3 months (81.38±59.19 cm2. Our study cohort was composed mainly of elderly patients taking multiple drugs to treat comorbidities, who have a high risk of drug

  18. Neuropathic pain management in children.

    LENUS (Irish Health Repository)

    Hyde, Catherine

    2012-10-01

    There are difficulties in assessing, managing, and evaluating neuropathic pain in dying children, particularly those with neurological impairment. Neuropathic pain in children often presents differently to how it presents in the adult population. Comprehensive assessment as well as pharmacological and non-pharmacological interventions are crucial to its successful management and frequently require input from an interdisciplinary team. Notwithstanding the need for further research, this paper brings together research papers, reviews, and clinical guidelines to present an exploration of existing evidence regarding care for children with neuropathic pain and their families.

  19. Neuropathic pain and dry eye.

    Science.gov (United States)

    Galor, Anat; Moein, Hamid-Reza; Lee, Charity; Rodriguez, Adriana; Felix, Elizabeth R; Sarantopoulos, Konstantinos D; Levitt, Roy C

    2018-01-01

    Dry eye is a common, multifactorial disease currently diagnosed by a combination of symptoms and signs. Its epidemiology and clinical presentation have many similarities with neuropathic pain outside the eye. This review highlights the similarities between dry eye and neuropathic pain, focusing on clinical features, somatosensory function, and underlying pathophysiology. Implications of these similarities on the diagnosis and treatment of dry eye are discussed. Published by Elsevier Inc.

  20. Neuropathic pain: A personal case reflection on a critical incident

    Directory of Open Access Journals (Sweden)

    Balaji P Duraisamy

    2011-01-01

    Full Text Available Neuropathic pain is a distressing symptom for the patient and a difficult symptom for the physician to treat. There is lack of evidence-based clinical guidelines for the management of malignant neuropathic pain. The case reflection is a personal account of what has been learnt from a critical incident in a particular patient in the management of neuropathic pain. Psychological issues are known to increase pain percetion and affect the quality of life. The case reflection explores problem areas, defines lacunae in knowledge, and demonstrates active learning of the management of neuropathic pain through reflective practice.

  1. Central Neuropathic Pain in Spinal Cord Injury

    Science.gov (United States)

    Lee, Sujin; Zhao, Xing; Hatch, Maya; Chun, Sophia; Chang, Eric

    2015-01-01

    Spinal cord injury (SCI) is a devastating medical condition affecting 1.2 million people in the United States. Central neuropathic pain is one of the most common medical complications of SCI. Current treatment options include opioids, antiepileptic agents such as gabapentin, antispastic agents such as baclofen or tizanidine, and tricyclic acid. Other options include complementary, nonpharmacological treatment such as exercise or acupuncture, interventional treatments, and psychological approaches. Although these treatment options exist, central neuropathic pain in patients with SCI is still extremely difficult to treat because of its complexity. To develop and provide more effective treatment options to these patients, proper assessment of and classification tools for central neuropathic pain, as well as a better understanding of the pathophysiology, are needed. A combination of approaches, from standard general pain assessments to medically specific questions unique to SCI pathophysiology, is essential for this population. A multidisciplinary approach to patient care, in addition with a better understanding of pathophysiology and diagnosis, will lead to improved management and treatment of patients with SCI displaying central neuropathic pain. Here we summarize the most recent classification tools, pathophysiology, and current treatment options for patients with SCI with central neuropathic pain. PMID:25750485

  2. Pharmacologic management of neuropathic pain.

    Science.gov (United States)

    Gordon, Debra B; Love, Georgette

    2004-12-01

    The mechanisms underlying the pathogenesis of neuropathic pain are complex but are gradually coming to light. Agents that have been found effective in a variety of neuropathic pain conditions include drugs that act to modulate (a) sodium or calcium channels, (b) N-methyl-D-aspartate receptors, (c) norepinephrine or serotonin reuptake, (d) opioid receptors, and (e) other cellular processes. Clinical trials have primarily evaluated these treatments for postherpetic neuralgia and painful diabetic neuropathy, the two most common types of neuropathic pain. Nonetheless, the identification of effective treatment regimens remains challenging, often because multiple mechanisms may be operating in a given patient giving rise to the same symptom. Alternatively, a single mechanism may be responsible for multiple symptoms. Currently available diagnostic tools are inadequate to determine the best treatment using a mechanism-based model. Clinically, drug treatment of neuropathic pain is often a matter of treatment trials. This article presents a summary of available clinical information on first-line and lesser-known treatments for neuropathic pain.

  3. Combination treatment of neuropathic pain

    DEFF Research Database (Denmark)

    Holbech, Jakob Vormstrup; Jung, Anne; Jonsson, Torsten

    2017-01-01

    BACKGROUND: Current Danish treatment algorithms for pharmacological treatment of neuropathic pain (NeP) are tricyclic antidepressants (TCA), gabapentin and pregabalin as first-line treatment for the most common NeP conditions. Many patients have insufficient pain relief on monotherapy, but combin...

  4. Topical combinations aimed at treating microvascular dysfunction reduce allodynia in rat models of CRPS-I and neuropathic pain.

    Science.gov (United States)

    Ragavendran, J Vaigunda; Laferrière, André; Xiao, Wen Hua; Bennett, Gary J; Padi, Satyanarayana S V; Zhang, Ji; Coderre, Terence J

    2013-01-01

    Growing evidence indicates that various chronic pain syndromes exhibit tissue abnormalities caused by microvasculature dysfunction in the blood vessels of skin, muscle, or nerve. We tested whether topical combinations aimed at improving microvascular function would relieve allodynia in animal models of complex regional pain syndrome type I (CRPS-I) and neuropathic pain. We hypothesized that topical administration of either α(2)-adrenergic (α(2)A) receptor agonists or nitric oxide (NO) donors combined with either phosphodiesterase (PDE) or phosphatidic acid (PA) inhibitors would effectively reduce allodynia in these animal models of chronic pain. Single topical agents produced significant dose-dependent antiallodynic effects in rats with chronic postischemia pain, and the antiallodynic dose-response curves of PDE and PA inhibitors were shifted 2.5- to 10-fold leftward when combined with nonanalgesic doses of α(2)A receptor agonists or NO donors. Topical combinations also produced significant antiallodynic effects in rats with sciatic nerve injury, painful diabetic neuropathy, and chemotherapy-induced painful neuropathy. These effects were shown to be produced by a local action, lasted up to 6 hours after acute treatment, and did not produce tolerance over 15 days of chronic daily dosing. The present results support the hypothesis that allodynia in animal models of CRPS-I and neuropathic pain is effectively relieved by topical combinations of α(2)A or NO donors with PDE or PA inhibitors. This suggests that topical treatments aimed at improving microvascular function may reduce allodynia in patients with CRPS-I and neuropathic pain. This article presents the synergistic antiallodynic effects of combinations of α(2)A or NO donors with PDE or PA inhibitors in animal models of CRPS-I and neuropathic pain. The data suggest that effective clinical treatment of chronic neuropathic pain may be achieved by therapies that alleviate microvascular dysfunction in affected

  5. Correlation between pain response and improvements in patient-reported outcomes and health-related quality of life in duloxetine-treated patients with diabetic peripheral neuropathic pain

    Directory of Open Access Journals (Sweden)

    Ogawa K

    2015-08-01

    Full Text Available Kei Ogawa,1 Shinji Fujikoshi,2 William Montgomery,3 Levent Alev1 1Medical Science, 2Statistical Science, Eli Lilly Japan K.K., Kobe, Japan; 3Global Patient Outcomes and Real World Evidence, Eli Lilly Australia Pty Ltd, West Ryde, NSW, Australia Objective: We assessed whether quality of life (QoL improvement in duloxetine-treated patients with diabetic peripheral neuropathic pain (DPNP correlates with the extent of pain relief.Methods: Pooled data from three multicountry, double-blind, 12-week, placebo-controlled trials of duloxetine-treated (duloxetine 60 mg once daily; total number =335 patients with DPNP were analyzed. Based on improvement in 24-hour average pain scores, patients were stratified into four groups. Improvement in QoL, which was measured as the change from baseline in two patient-reported health outcome measures (Short Form [SF]-36 and five-dimension version of the EuroQol Questionnaire [EQ-5D], was evaluated and compared among the four groups. Pearson’s correlation coefficient was calculated to assess the correlation between improvement in pain scores and improvement in QoL.Results: The group with more pain improvement generally showed greater mean change from baseline in all of the SF-36 scale scores and on the EQ-5D index. Pearson’s correlation coefficients ranged from 0.114 to 0.401 for the SF-36 scale scores (P<0.05, and it was 0.271 for the EQ-5D (P<0.001.Conclusion: Improvement in pain scores was positively correlated with improvement in QoL and patient-reported outcomes in duloxetine-treated patients. Keywords: diabetic peripheral neuropathic pain, duloxetine, efficacy, function, quality of life

  6. Cortical stimulation and neuropathic pain

    Directory of Open Access Journals (Sweden)

    Cristiane Cagnoni Ramos

    2015-02-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2015v28n2p1 This paper is a review of physiological and behavioral data on motor cortex stimulation (MCS and its role in persistent neuropathic pain. MCS has been widely used in clinical medicine as a tool for the management of pain that does not respond satisfactorily to any kind of conventional analgesia. Some important mechanisms involved in nociceptive modulation still remains unclear. The aim of this study was to describe the mechanisms involved in neuropathic pain and introduce the effectiveness of electrical stimulation of the motor cortex used in the treatment of this disease. The ascending pain pathways are activated by peripheral receptors, in which there is the transduction of a chemical, physical or mechanical stimulus as a nerve impulse, where this impulse is transmitted to the dorsal horn of the spinal cord, which connects with second-order neurons and ascends to different locations in the central nervous system where the stimulus is perceived as pain. Because MCS has been proved to modulate this pathway in the motor cortex, it has been studied to mimic its effects in clinical practice and improve the treatments used for chronic pain. MCS has gained much attention in recent years due to its action in reversing chronic neuropathic pain, this being more effective than electrical stimulation at different locations and related pain nuclei.

  7. Cortical stimulation and neuropathic pain

    Directory of Open Access Journals (Sweden)

    Cristiane Cagnoni Ramos

    2015-05-01

    Full Text Available This paper is a review of physiological and behavioral data on motor cortex stimulation (MCS and its role in persistent neuropathic pain. MCS has been widely used in clinical medicine as a tool for the management of pain that does not respond satisfactorily to any kind of conventional analgesia. Some important mechanisms involved in nociceptive modulation still remains unclear. The aim of this study was to describe the mechanisms involved in neuropathic pain and introduce the effectiveness of electrical stimulation of the motor cortex used in the treatment of this disease. The ascending pain pathways are activated by peripheral receptors, in which there is the transduction of a chemical, physical or mechanical stimulus as a nerve impulse, where this impulse is transmitted to the dorsal horn of the spinal cord, which connects with second-order neurons and ascends to different locations in the central nervous system where the stimulus is perceived as pain. Because MCS has been proved to modulate this pathway in the motor cortex, it has been studied to mimic its effects in clinical practice and improve the treatments used for chronic pain. MCS has gained much attention in recent years due to its action in reversing chronic neuropathic pain, this being more effective than electrical stimulation at different locations and related pain nuclei.

  8. Spinal Gap Junction Channels in Neuropathic Pain

    OpenAIRE

    Jeon, Young Hoon; Youn, Dong Ho

    2015-01-01

    Damage to peripheral nerves or the spinal cord is often accompanied by neuropathic pain, which is a complex, chronic pain state. Increasing evidence indicates that alterations in the expression and activity of gap junction channels in the spinal cord are involved in the development of neuropathic pain. Thus, this review briefly summarizes evidence that regulation of the expression, coupling, and activity of spinal gap junction channels modulates pain signals in neuropathic pain states induced...

  9. Complex Regional Pain Syndrome (CRPS/RSD and Neuropathic Pain: Role of Intravenous Bisphosphonates as Analgesics

    Directory of Open Access Journals (Sweden)

    Jennifer Yanow

    2008-01-01

    Full Text Available Neuropathic pain is a sequela of dysfunction, injuries, or diseases of the peripheral and/or central nervous system pain pathways, which has historically been extremely difficult to treat. Complex regional pain syndrome (CRPS types 1 and 2 are neuropathic pain conditions that have a long history in the medical literature but whose pathophysiology remains elusive and whose available treatment options remain few. While an exact animal model for CRPS doesn't yet exist, there are several animal models of neuropathic pain that develop behaviors of hypersensitivity, one of the hallmark signs of neuropathic pain in humans.

  10. Neuropathic pain in leprosy: symptom profile characterization and comparison with neuropathic pain of other etiologies.

    Science.gov (United States)

    Raicher, Irina; Stump, Patrick Raymond Nicolas Andre Ghislain; Harnik, Simone Bega; de Oliveira, Rodrigo Alves; Baccarelli, Rosemari; Marciano, Lucia H S C; Ura, Somei; Virmond, Marcos C L; Teixeira, Manoel Jacobsen; de Andrade, Daniel Ciampi

    2018-03-01

    Previous studies reported a high prevalence of neuropathic pain in leprosy, being especially present in "pharmacologically cured" patients. The presence of neuropathic pain in leprosy poses a supplementary burden in patient's quality of life, daily activities, and mood. The aim of this study was to assess whether neuropathic pain in leprosy has similar symptom profile as neuropathic pain of other etiologies and to retrospectively assess the efficacy of neuropathic pain medications regularly prescribed to leprosy. Leprosy and nonleprosy patients had their neuropathic pain characterized by the neuropathic pain symptom inventory (NPSI, ranges from 0 to 100, with 100 being the maximal neuropathic pain intensity) in a first visit. In a second visit, leprosy patients who had significant pain and received pharmacological treatment in the first evaluation were reassessed (NPSI) and had their pain profile and treatment response further characterized, including information on drugs prescribed for neuropathic pain and their respective pain relief. The pain characteristics based on NPSI did not significantly differ between leprosy and nonleprosy neuropathic pain patients in visit 1 after correction for multiple analyses, and cluster analyses confirmed these findings (ie, no discrimination between leprosy and nonleprosy groups; Pearson χ2 = 0.072, P = 0.788). The assessment of pain relief response and the drugs taken by each patient, linear regression analysis showed that amitriptyline, when effective, had the highest percentage of analgesic relief. Neuropathic pain in leprosy is as heterogeneous as neuropathic pain of other etiologies, further supporting the concept that neuropathic pain is a transetiological entity. Neuropathic pain in leprosy may respond to drugs usually used to control pain of neuropathic profile in general, and amitriptiline may constitute a potential candidate drug for future formal clinical trials aimed at controlling neuropathic pain in leprosy.

  11. Neuropathic pain is not adequately treated in the older general population: Results from the KORA F4 survey.

    Science.gov (United States)

    Meisinger, Christa; Bongaerts, Brenda W C; Heier, Margit; Amann, Ute; Kowall, Bernd; Herder, Christian; Rückert-Eheberg, Ina-Maria; Rathmann, Wolfgang; Ziegler, Dan

    2018-05-24

    We evaluated the pharmacological treatment of distal sensorimotor polyneuropathy (DSPN) among older subjects from the general population. The study included subjects aged 61 to 82 years from the KORA F4 survey (2006-2008). DSPN was defined as the presence of bilaterally impaired foot-vibration perception and/or bilaterally impaired foot-pressure sensation. Pain intensity was assessed with the painDETECT questionnaire. From the included 1076 older persons, 172 (16%) persons reported pain in the lower extremities and DSPN was present in 150 (14%) subjects. Forty-eight people with pain in the lower extremities reported DSPN. Only 38% of the subjects with DSPN reporting an average pain level of ≥4 during the past 4 weeks received medical treatment, predominantly nonsteroidal anti-inflammatory drugs (NSAIDs 20% and opioids 12%). The medication of choice for neuropathic pain, antidepressants, anticonvulsants, and opioids was relatively being underused. However, opioids and neuropathy preparations were prescribed preferably for subjects with painful DSPN. In the older general population, only a small proportion of subjects with painful DSPN receive analgesic pharmacotherapy. Although not recommended by guidelines for the treatment of neuropathic pain, NSAIDs were the most frequently used class of analgesic drugs. Copyright © 2018 John Wiley & Sons, Ltd.

  12. Systemic Inflammatory and Th17 Immune Activation among Patients Treated for Lumbar Radiculopathy Exceeds that of Patients Treated for Persistent Postoperative Neuropathic Pain.

    Science.gov (United States)

    Shamji, Mohammed F; Guha, Daipayan; Paul, Darcia; Shcharinsky, Alina

    2017-09-01

    The pathophysiology of lumbar radiculopathy includes both mechanical compression and biochemical irritation of apposed neural elements. Inflammatory and immune cytokines have been implicated, induced by systemic exposure of immune-privileged intervertebral disc tissue. Surgical intervention provides improved symptoms and quality of life, but persistent postoperative neuropathic pain (PPNP) afflicts a significant fraction of patients. To compare the inflammatory and immune phenotypes among patients undergoing structural surgery for lumbar radiculopathy and spinal cord stimulation for neuropathic pain. Consecutive patients undergoing surgical intervention for lumbar radiculopathy or neuropathic pain were studied. Demographic data included age, gender, and VAS and neuropathic pain scores. Serum was evaluated for cytokine levels (IL-6, Il-17, TNF-α) and cellular content [white blood cell (WBC)/differential, lymphocyte subtypes]. The primary analysis differentiated molecular and cellular profiles between radiculopathy and neuropathic pain patients. Subgroup analysis within the surgical radiculopathy population compared those patients achieving relief of symptoms and those with PPNP. Heightened IL-6, Il-17, and TNF-α levels were observed for the lumbar radiculopathy group compared with the neuropathic pain group. This was complemented by higher WBC count and a greater fraction of Th17 lymphocytes among radiculopathy patients. In the lumbar discectomy subgroup, pain relief was seen among patients with preoperatively elevated IL-17 levels. Those patients with PPNP refractory to surgical discectomy exhibited normal cytokine levels. Differences in Th17 immune activation are seen among radiculopathy and neuropathic pain patients. These cellular and molecular profiles may be translated into biomarkers to improve patient selection for structural spine surgery. Copyright © 2017 by the Congress of Neurological Surgeons

  13. Neuropathic pain in spinal cord injury.

    Science.gov (United States)

    Nakipoglu-Yuzer, Guidal F; Atçı, Nermin; Ozgirgin, Nese

    2013-01-01

    Several studies have described pain prevalence, risk factors, pain and medical variables in spinal cord injury (SCI) populations. In this study on traumatic SCI in Turkey, we surveyed the neuropathic pain experiences during in-patient rehabilitation and defined the relationships between neuropathic pain and demographic and SCI characteristics of patients. To survey the neuropathic pain experiences during in-patient rehabilitation in traumatic SCI and to define the relationships between neuropathic pain and demographic and SCI-related characteristics of patients. Descriptive study. Physicial Medicine and Rehabilitation inpatient clinic, Ankara, Turkey Sixty-nine SCI patients as inpatients were included in this descriptive study. All patients demographic and SCI-related characteristics were enrolled. The diagnosis of neuropathic pain was made with the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) Pain Scale. Location of pain and pain description, relation to time and severity according to McGill Pain Questionnaire (MPQ) were enrolled. The neuropathic pain localization was below the lesion level in 67 (97.1%) and at the lesion level in 2 (2.9%) patients. The pain was at the hip and leg regions in 36 (52.2%) patients. The neuropathic pain was defined as burning in 27 (39.1%), aching in 26 (37.7%), sharp in 4 (5.8%), stinging in 3 (4.3%), and cramping in 3 (4.3%). We did not find a significant difference between demographic and SCI-related characteristics and the localization of neuropathic pain for the patients (P > 0.05). There was no significant difference according to pain description by MPQ and pain localization (P > 0.05). We found a significant relationship between the patient's lesion level and the region of pain (P neuropathic pain due to SCI to be mostly below the lesion level with a burning or aching character and we did not find a significant relationship between the demographic and SCI-related characteristics of the patient and the pain

  14. Poly(ADP-ribose) polymerase inhibition reveals a potential mechanism to promote neuroprotection and treat neuropathic pain

    OpenAIRE

    Komirishetty, Prashanth; Areti, Aparna; Gogoi, Ranadeep; Sistla, Ramakrishna; Kumar, Ashutosh

    2016-01-01

    Neuropathic pain is triggered by the lesions to peripheral nerves which alter their structure and function. Neuroprotective approaches that limit the pathological changes and improve the behavioral outcome have been well explained in different experimental models of neuropathy but translation of such strategies to clinics has been disappointing. Experimental evidences revealed the role of free radicals, especially peroxynitrite after the nerve injury. They provoke oxidative DNA damage and con...

  15. Neuropathic pain - Current concepts

    African Journals Online (AJOL)

    Department of Family Medicine, University of Pretoria and Kalafong Hospital ... The aim of treatment is to assist the patient in managing the pain and to improve function ..... The incidence of true addiction to strong opioids in the management.

  16. PHARMACOTHERAPY IN ELDERLY NEUROPATHIC PAIN

    Directory of Open Access Journals (Sweden)

    Thomas Eko P

    2013-10-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 The incidence of pain increases with age. Neuropathic pain are common in elderly patients and pose challenges in both their diagnosis and treatment. The most common neuropathic pain in elderly are radiculopathy due to foraminal or spinal stenosis, diabetic neuropathy, and postherpetic neuralgia. Pain in the elderly is often unrecognized and undertreated. The main problem with pain in older adults relates to impaired quality of life secondary to pain which may be expressed by depression (including increased suicide risk, anxiety, sleep disruption, appetite disturbance, and weight loss, cognitive impairment, and limitations in the performance of daily activities. Pain management in elderly patients requires a different perspective from that of younger patients. Causes, comorbidities, and responses to both pain and its treatment differ between young healthy and older patients. Effective pain management in elderly patients should include both pharmacologic and nonpharmacologic strategies. Pharmacological approaches are the first line of pain management in older person for neuropathic pain. Pharmacologic strategies call for administration of nonopioid analgesics, opioid analgesics, and adjuvant medication. Polypharmacy, drug-drug and drug-disease interactions, age-associated changes in drug metabolism, and the high frequency of adverse drug reactions need to be carefully considered in using medications in this population /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso

  17. Lumbar neuropathic pain of lower limbs treated by spinal infusion of ziconotide a case – report

    Directory of Open Access Journals (Sweden)

    Luca Quadrino

    2008-09-01

    Full Text Available The Author reports the case of a patient with severe lumbar pain unresponsive to NSAIDs. Initial treatment with tramadol gave poor results and a new protocol with hydromorphone – pregabalin was started. The analgesic response was observed only following high hydromorphone doses, associated with unacceptable side effects. A spinal device for continuous intrathecal infusion was then implanted, in order to administer ziconotide, a new opioid drug. Associated therapy included hydromorphone – pregabalin. At the 4 mcg/die dose ziconotide resulted highly effective (with a VAS reduction pain 6-7 to 2-3 even at 1st day after implantation; in addition at day 10, opioid dose was strongly reduced and pregabalin withdrawn. The treatment was associated with a good tolerability. The encouraging results prompted the Author to test ziconotide in further cases of severe chronic pain.

  18. Puerarin Alleviates Neuropathic Pain by Inhibiting Neuroinflammation in Spinal Cord

    OpenAIRE

    Ming Liu; Kaijun Liao; Changxi Yu; Xuejun Li; Suhuan Liu; Shuyu Yang

    2014-01-01

    Neuropathic pain responds poorly to drug treatments, and partial relief is achieved in only about half of the patients. Puerarin, the main constituent of Puerariae Lobatae Radix, has been used extensively in China to treat hypertension and tumor. The current study examined the effects of puerarin on neuropathic pain using two most commonly used animal models: chronic constriction injury (CCI) and diabetic neuropathy. We found that consecutive intrathecal administration of puerarin (4–100 nM) ...

  19. The neurosurgical treatment of neuropathic facial pain.

    Science.gov (United States)

    Brown, Jeffrey A

    2014-04-01

    This article reviews the definition, etiology and evaluation, and medical and neurosurgical treatment of neuropathic facial pain. A neuropathic origin for facial pain should be considered when evaluating a patient for rhinologic surgery because of complaints of facial pain. Neuropathic facial pain is caused by vascular compression of the trigeminal nerve in the prepontine cistern and is characterized by an intermittent prickling or stabbing component or a constant burning, searing pain. Medical treatment consists of anticonvulsant medication. Neurosurgical treatment may require microvascular decompression of the trigeminal nerve. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. AAPT Diagnostic Criteria for Central Neuropathic Pain

    DEFF Research Database (Denmark)

    Widerstrom-Noga, Eva; Loeser, John D.; Jensen, Troels Staehelin

    2017-01-01

    Central neuropathic pain, which is pain caused by a lesion or disease of the central somatosensory nervous system, is a serious consequence of spinal cord injury, stroke, multiple sclerosis, and other conditions affecting the central nervous system. A collaborative effort between the Analgesic....... This article focuses on central neuropathic pain associated with spinal cord injury, stroke, and multiple sclerosis, but the AAPT framework can be extended to central pain due to other causes such as traumatic brain injury. The classification of central neuropathic pain is organized according to the AAPT...

  1. Tramadol for neuropathic pain in adults.

    Science.gov (United States)

    Duehmke, Rudolf Martin; Derry, Sheena; Wiffen, Philip J; Bell, Rae F; Aldington, Dominic; Moore, R Andrew

    2017-06-15

    This review is an update of a review of tramadol for neuropathic pain, published in 2006; updating was to bring the review in line with current standards. Neuropathic pain, which is caused by a lesion or disease affecting the somatosensory system, may be central or peripheral in origin. Peripheral neuropathic pain often includes symptoms such as burning or shooting sensations, abnormal sensitivity to normally painless stimuli, or an increased sensitivity to normally painful stimuli. Neuropathic pain is a common symptom in many diseases of the peripheral nervous system. To assess the analgesic efficacy of tramadol compared with placebo or other active interventions for chronic neuropathic pain in adults, and the adverse events associated with its use in clinical trials. We searched CENTRAL, MEDLINE, and Embase for randomised controlled trials from inception to January 2017. We also searched the reference lists of retrieved studies and reviews, and online clinical trial registries. We included randomised, double-blind trials of two weeks' duration or longer, comparing tramadol (any route of administration) with placebo or another active treatment for neuropathic pain, with subjective pain assessment by the participant. Two review authors independently extracted data and assessed trial quality and potential bias. Primary outcomes were participants with substantial pain relief (at least 50% pain relief over baseline or very much improved on Patient Global Impression of Change scale (PGIC)), or moderate pain relief (at least 30% pain relief over baseline or much or very much improved on PGIC). Where pooled analysis was possible, we used dichotomous data to calculate risk ratio (RR) and number needed to treat for an additional beneficial outcome (NNT) or harmful outcome (NNH), using standard methods. We assessed the quality of the evidence using GRADE and created 'Summary of findings' tables. We identified six randomised, double-blind studies involving 438 participants

  2. Food-Derived Natural Compounds for Pain Relief in Neuropathic Pain.

    Science.gov (United States)

    Lim, Eun Yeong; Kim, Yun Tai

    2016-01-01

    Neuropathic pain, defined as pain caused by a lesion or disease of the somatosensory nervous system, is characterized by dysesthesia, hyperalgesia, and allodynia. The number of patients with this type of pain has increased rapidly in recent years. Yet, available neuropathic pain medicines have undesired side effects, such as tolerance and physical dependence, and do not fully alleviate the pain. The mechanisms of neuropathic pain are still not fully understood. Injury causes inflammation and immune responses and changed expression and activity of receptors and ion channels in peripheral nerve terminals. Additionally, neuroinflammation is a known factor in the development and maintenance of neuropathic pain. During neuropathic pain development, the C-C motif chemokine receptor 2 (CCR2) acts as an important signaling mediator. Traditional plant treatments have been used throughout the world for treating diseases. We and others have identified food-derived compounds that alleviate neuropathic pain. Here, we review the natural compounds for neuropathic pain relief, their mechanisms of action, and the potential benefits of natural compounds with antagonistic effects on GPCRs, especially those containing CCR2, for neuropathic pain treatment.

  3. Antidepressants in the treatment of neuropathic pain

    DEFF Research Database (Denmark)

    Sindrup, Søren H.; Otto, Marit; Finnerup, Nanna Brix

    2005-01-01

    Neuropathic pain is due to lesion or dysfunction of the peripheral or central nervous system. Tricyclic antidepressants and anticonvulsants have long been the mainstay of treatment of this type of pain. Tricyclic antidepressants may relieve neuropathic pain by their unique ability to inhibit...... presynaptic reuptake of the biogenic amines serotonin and noradrenaline, but other mechanisms such as N-methyl-D-aspartate receptor and ion channel blockade probably also play a role in their pain-relieving effect. The effect of tricyclic antidepressants in neuropathic pain in man has been demonstrated...... in numerous randomised, controlled trials, and a few trials have shown that serotonin noradrenaline and selective serotonin reuptake inhibitor antidepressants also relieve neuropathic pain although with lower efficacy. Tricyclic antidepressants will relieve one in every 2-3 patients with peripheral...

  4. The evidence for pharmacological treatment of neuropathic pain.

    Science.gov (United States)

    Finnerup, Nanna Brix; Sindrup, Søren Hein; Jensen, Troels Staehelin

    2010-09-01

    Randomized, double-blind, placebo-controlled trials on neuropathic pain treatment are accumulating, so an updated review of the available evidence is needed. Studies were identified using MEDLINE and EMBASE searches. Numbers needed to treat (NNT) and numbers needed to harm (NNH) values were used to compare the efficacy and safety of different treatments for a number of neuropathic pain conditions. One hundred and seventy-four studies were included, representing a 66% increase in published randomized, placebo-controlled trials in the last 5 years. Painful poly-neuropathy (most often due to diabetes) was examined in 69 studies, postherpetic neuralgia in 23, while peripheral nerve injury, central pain, HIV neuropathy, and trigeminal neuralgia were less often studied. Tricyclic antidepressants, serotonin noradrenaline reuptake inhibitors, the anticonvulsants gabapentin and pregabalin, and opioids are the drug classes for which there is the best evidence for a clinical relevant effect. Despite a 66% increase in published trials only a limited improvement of neuropathic pain treatment has been obtained. A large proportion of neuropathic pain patients are left with insufficient pain relief. This fact calls for other treatment options to target chronic neuropathic pain. Large-scale drug trials that aim to identify possible subgroups of patients who are likely to respond to specific drugs are needed to test the hypothesis that a mechanism-based classification may help improve treatment of the individual patients. Copyright (c) 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  5. Effect of Xylopic Acid on Paclitaxel-induced Neuropathic pain in rats ...

    African Journals Online (AJOL)

    Xylopic acid, a diterpenoid isolated from the fruits of Xylopia aethiopica has demonstrated analge-sic properties in acute pain models. It was therefore evaluated for its analgesic properties in paclitaxel-induced neuropathic pain, a type of pain difficult to treat clinically. Neuropathic pain was induced in rats by injecting 2 mg ...

  6. ARA290 : a novel treatment for neuropathic pain in sarcoidosis

    NARCIS (Netherlands)

    Heij, L.

    2016-01-01

    The general aim of this thesis is to investigate small fiber neuropathy in sarcoidosis and to asses whether ARA290 is a possible new agent to treat the neuropathic complaints in sarcoidosis population. The results of the various ARA290 trials in painful sarcoidosis are discussed. Painful neuropathy

  7. Neuropathic pain: targeting the melatonin MT receptor

    African Journals Online (AJOL)

    inflammatory drugs (NSAIDs) and opioids is highly effective in ... to drug treatment. .... effects in chronic neuropathic pain, which are mediated by the .... Reiter R, Tan D, Kim S, Cruz M. Delivery of pineal melatonin to the brain and SCN:.

  8. A Review of Neuropathic Pain: From Diagnostic Tests to Mechanisms

    OpenAIRE

    Truini, Andrea

    2017-01-01

    Neuropathic pain develops when the somatosensory nervous system is affected by a lesion or disease. Diagnostic tests aimed at assessing somatosensory afferent pathway damage are therefore useful for diagnosing neuropathic pain. Neuropathic pain manifests with a range of different symptoms such as ongoing burning pain, squeezing or pressure pain, paroxysmal electric shock-like sensations, stabbing pain, or mechanical dynamic allodynia. The various types of neuropathic pain are associated with ...

  9. Neuropathic low back pain in clinical practice.

    Science.gov (United States)

    Baron, R; Binder, A; Attal, N; Casale, R; Dickenson, A H; Treede, R-D

    2016-07-01

    Low back pain (LBP) is one of the most common chronic pain conditions. This paper reviews the available literature on the role of neuropathic mechanisms in chronic LBP and discusses implications for its clinical management, with a particular focus on pharmacological treatments. Literature searches were performed in PubMed, key pain congresses and ProQuest Dialog to identify published evidence on neuropathic back pain and its management. All titles were assessed for relevant literature. Chronic LBP comprises both nociceptive and neuropathic components, however, the neuropathic component appears under-recognized and undertreated. Neuropathic pain (NP) is challenging to manage. Many patients with chronic LBP have pain that is refractory to existing treatments. Typically, less than half of patients experience clinically meaningful analgesia with oral pharmacotherapies; these are also associated with risks of adverse effects. Paracetamol and NSAIDs, although widely used for LBP, are unlikely to ameliorate the neuropathic component and data on the use of NP medications such as antidepressants and gabapentin/pregabalin are limited. While there is an unmet need for improved treatment options, recent data have shown tapentadol to have efficacy in the neuropathic component of LBP, and studies suggest that the capsaicin 8% patch and lidocaine 5% medicated plaster, topical analgesics available for the treatment of peripheral NP, may be a valuable additional approach for the management of neuropathic LBP. Chronic LBP often has an under-recognized neuropathic component, which can be challenging to manage, and requires improved understanding and better diagnosis and treatment. WHAT DOES THIS REVIEW ADD?: Increased recognition and improved understanding of the neuropathic component of low back pain raises the potential for the development of mechanism-based therapies. Open and retrospective studies suggest that agents like tapentadol and topical analgesics - such as the capsaicin

  10. Molecular Hydrogen Attenuates Neuropathic Pain in Mice

    Science.gov (United States)

    Kawaguchi, Masanori; Satoh, Yasushi; Otsubo, Yukiko; Kazama, Tomiei

    2014-01-01

    Neuropathic pain remains intractable and the development of new therapeutic strategies are urgently required. Accumulating evidence indicates that overproduction of oxidative stress is a key event in the pathogenesis of neuropathic pain. However, repeated intra-peritoneal or intrathecal injections of antioxidants are unsuitable for continuous use in therapy. Here we show a novel therapeutic method against neuropathic pain: drinking water containing molecular hydrogen (H2) as antioxidant. The effect of hydrogen on neuropathic pain was investigated using a partial sciatic nerve ligation model in mice. As indicators of neuropathic pain, temporal aspects of mechanical allodynia and thermal hyperalgesia were analysed for 3 weeks after ligation. Mechanical allodynia and thermal hyperalgesia were measured using the von Frey test and the plantar test, respectively. When mice were allowed to drink water containing hydrogen at a saturated level ad libitum after ligation, both allodynia and hyperalgesia were alleviated. These symptoms were also alleviated when hydrogen was administered only for the induction phase (from day 0 to 4 after ligation). When hydrogen was administered only for the maintenance phase (from day 4 to 21 after ligation), hyperalgesia but not allodynia was alleviated. Immunohistochemical staining for the oxidative stress marker, 4-hydroxy-2-nonenal and 8-hydroxydeoxyguanosine, showed that hydrogen administration suppressed oxidative stress induced by ligation in the spinal cord and the dorsal root ganglion. In conclusion, oral administration of hydrogen water may be useful for alleviating neuropathic pain in a clinical setting. PMID:24941001

  11. Puerarin Alleviates Neuropathic Pain by Inhibiting Neuroinflammation in Spinal Cord

    Directory of Open Access Journals (Sweden)

    Ming Liu

    2014-01-01

    Full Text Available Neuropathic pain responds poorly to drug treatments, and partial relief is achieved in only about half of the patients. Puerarin, the main constituent of Puerariae Lobatae Radix, has been used extensively in China to treat hypertension and tumor. The current study examined the effects of puerarin on neuropathic pain using two most commonly used animal models: chronic constriction injury (CCI and diabetic neuropathy. We found that consecutive intrathecal administration of puerarin (4–100 nM for 7 days inhibited the mechanical and thermal nociceptive response induced by CCI and diabetes without interfering with the normal pain response. Meanwhile, in both models puerarin inhibited the activation of microglia and astroglia in the spinal dorsal horn. Puerarin also reduced the upregulated levels of nuclear factor-κB (NF-κB and other proinflammatory cytokines, such as IL-6, IL-1β, and TNF-α, in the spinal cord. In summary, puerarin alleviated CCI- and diabetes-induced neuropathic pain, and its effectiveness might be due to the inhibition of neuroinflammation in the spinal cord. The anti-inflammation effect of puerarin might be related to the suppression of spinal NF-κB activation and/or cytokines upregulation. We conclude that puerarin has a significant effect on alleviating neuropathic pain and thus may serve as a therapeutic approach for neuropathic pain.

  12. Puerarin alleviates neuropathic pain by inhibiting neuroinflammation in spinal cord.

    Science.gov (United States)

    Liu, Ming; Liao, Kaijun; Yu, Changxi; Li, Xuejun; Liu, Suhuan; Yang, Shuyu

    2014-01-01

    Neuropathic pain responds poorly to drug treatments, and partial relief is achieved in only about half of the patients. Puerarin, the main constituent of Puerariae Lobatae Radix, has been used extensively in China to treat hypertension and tumor. The current study examined the effects of puerarin on neuropathic pain using two most commonly used animal models: chronic constriction injury (CCI) and diabetic neuropathy. We found that consecutive intrathecal administration of puerarin (4-100 nM) for 7 days inhibited the mechanical and thermal nociceptive response induced by CCI and diabetes without interfering with the normal pain response. Meanwhile, in both models puerarin inhibited the activation of microglia and astroglia in the spinal dorsal horn. Puerarin also reduced the upregulated levels of nuclear factor-κB (NF-κB) and other proinflammatory cytokines, such as IL-6, IL-1β, and TNF-α, in the spinal cord. In summary, puerarin alleviated CCI- and diabetes-induced neuropathic pain, and its effectiveness might be due to the inhibition of neuroinflammation in the spinal cord. The anti-inflammation effect of puerarin might be related to the suppression of spinal NF-κB activation and/or cytokines upregulation. We conclude that puerarin has a significant effect on alleviating neuropathic pain and thus may serve as a therapeutic approach for neuropathic pain.

  13. Effects of fisetin on oxaliplatin-induced neuropathic pain in mice

    OpenAIRE

    Hong Liu; Chaohua Wang; Hua Yang; Fengjie Wang

    2015-01-01

    Common chemotherapeutic agents such as oxaliplatin often cause neuropathic pain during cancer treatment in patients. Such neuropathic pain is difficult to treat and responds poorly to common analgesics, which represents a challenging clinical issue. Fisetin is a naturally occurring flavonoid and this study tested the potential anti-hyperalgesic effects of fisetin in a mice model of oxaliplatin-induced neuropathic pain. Fisetin (1-4 mg/kg, i.p.) did not significantly alter the mechanical hyper...

  14. Neuropathic pain in the orofacial region: The role of pain history. A retrospective study.

    Science.gov (United States)

    Dieb, W; Moreau, N; Chemla, I; Descroix, V; Boucher, Y

    2017-06-01

    Orofacial neuropathic pain is often difficult to treat, mostly because of still unclear underlying mechanisms. The occurrence of such neuropathic pain varies depending on different factors, of which preexisting preoperative pain seems to be of high importance. The aim of this study was thus to test the hypothesis that prior history of pain could indeed be considered a risk factor for the development of orofacial neuropathic pain in the same region. The study was performed in the dental department of the Groupe Hospitalier Pitié-Salpêtrière (GHPS) in Paris, France. We investigated the presence of prior inflammatory pain before development of orofacial neuropathic pain in 56 patients. For each patient file, the following items were collected: age, gender; medical history; diagnosis; description of the pain (at time of consultation); presence or absence of prior dental treatment; date and type of dental treatment received. 41 patients (73%) of orofacial neuropathic pain patients had a history of pain compatible with an inflammatory condition; 4% (n=2) did not report any prior pain and 23% (n=13) could not remember. Among the patients with documented history of pain prior to neuropathy, 88% (n=36) received surgical treatment; 61%, (n=25) endodontic treatment and 22%, (n=9) restorative treatment. All eventually received endodontic treatment or tooth extraction. These dental treatments are compatible with the hypothesis of prior inflammatory pain in these patients. These results support the hypothesis that prior inflammatory pain could favor the development of orofacial neuropathic pain. Prevention and treatment of inflammatory trigeminal pain may therefore play a key role in preventing future neuropathic pain development. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  15. [Prevalence and aetiopathogenesis of neuropathic pain in elderly cancer patients].

    Science.gov (United States)

    Cabezón-Gutiérrez, Luis; Custodio-Cabello, Sara; Khosravi-Shahi, Parham

    2016-01-01

    The prevalence of neuropathic pain is difficult to estimate as most studies evaluating chronic pain do not differentiate neuropathic from nociceptive pain. There are only a few studies of neuropathic pain in the elderly, specifically in the oncology population. This article is a non-systematic review of the relevant evidence on the prevalence and aetiopathogenesis of neuropathic cancer pain in the elderly. Copyright © 2015 SEGG. Published by Elsevier Espana. All rights reserved.

  16. Neuropathic Pain Following Poly-L-Lactic Acid (Sculptra) Injection.

    Science.gov (United States)

    Vrcek, Ivan; El-Sawy, Tarek; Chou, Eva; Allen, Theresa; Nakra, Tanuj

    Injectable fillers have become a prevalent means of facial rejuvenation and volume expansion. While typically well tolerated, serious complications have been reported. The authors present a case in which an otherwise healthy female with a history of multiple filler injections including poly-L-lactic acid, developed 3 weeks of neuropathic pain in the left temporal fossa following injection. To the best of the authors knowledge, neuropathic pain has not been reported as a complication following poly-L-lactic acid injection. The patient was treated with an injection of steroid and long-acting anesthetic with resolution of symptoms.

  17. Low Dose Vaporized Cannabis Significantly Improves Neuropathic Pain

    Science.gov (United States)

    Wilsey, Barth; Marcotte, Thomas D.; Deutsch, Reena; Gouaux, Ben; Sakai, Staci; Donaghe, Haylee

    2013-01-01

    We conducted a double-blind, placebo-controlled, crossover study evaluating the analgesic efficacy of vaporized cannabis in subjects, the majority of whom were experiencing neuropathic pain despite traditional treatment. Thirty-nine patients with central and peripheral neuropathic pain underwent a standardized procedure for inhaling either medium dose (3.53%), low dose (1.29%), or placebo cannabis with the primary outcome being VAS pain intensity. Psychoactive side-effects, and neuropsychological performance were also evaluated. Mixed effects regression models demonstrated an analgesic response to vaporized cannabis. There was no significant difference between the two active dose groups’ results (p>0.7). The number needed to treat (NNT) to achieve 30% pain reduction was 3.2 for placebo vs. low dose, 2.9 for placebo vs. medium dose, and 25 for medium vs. low dose. As these NNT are comparable to those of traditional neuropathic pain medications, cannabis has analgesic efficacy with the low dose being, for all intents and purposes, as effective a pain reliever as the medium dose. Psychoactive effects were minimal and well-tolerated, and neuropsychological effects were of limited duration and readily reversible within 1–2 hours. Vaporized cannabis, even at low doses, may present an effective option for patients with treatment-resistant neuropathic pain. PMID:23237736

  18. Ethanolic extract of Aloe vera ameliorates sciatic nerve ligation induced neuropathic pain

    Directory of Open Access Journals (Sweden)

    Swetha Kanyadhara

    2014-01-01

    Conclusion: The results of the present study validate the use of EEAV to treat neuropathic pain. This effect may be attributed to the decreased migration of neutrophils and due to the anti-oxidant properties of A. vera. Further studies to confirm the mechanism of action will help develop suitable A. vera formulations for neuropathic pain therapy .

  19. Characteristics of neuropathic pain in patients with spinal cord injury.

    Science.gov (United States)

    Jang, Joon Young; Lee, Seung Hoon; Kim, MinYoung; Ryu, Ju Seok

    2014-06-01

    To characterize neuropathic pain in patients with spinal cord injury (SCI) according to classification used in the study by Baron et al. (Baron classification), a classification of neuropathic pain based on the mechanism. To also compare the patterns of neuropathic pain in SCI patients with those in patients with other etiologies and to determine the differences in patterns of neuropathic pain between the etiologies. This was a descriptive cross-sectional study. We used the Baron classification to investigate the characteristics of neuropathic pain in SCI. Sixty-one SCI patients with neuropathic pain (The Leeds assessment of neuropathic symptoms and signs score ≥12) were enrolled in this study between November 2012 and August 2013, after excluding patients patients with visual analog scale (VAS) score patients, and patients with systemic disease or pain other than neuropathic pain. The most common pain characteristic was pricking pain followed by electrical pain and numbness. The mean VAS score of at-level neuropathic pain was 7.51 and that of below-level neuropathic pain was 6.83. All of the patients suffered from rest pain, but 18 (54.6%) patients with at-level neuropathic pain and 20 (50.0%) patients with below-level neuropathic pain suffered from evoked pain. There was no significant difference in between at-level and below-level neuropathic pains. The result was quite different from the characteristics of post-herpetic neuralgia, but it was similar to the characteristics of diabetic neuropathy as shown in the study by Baron et al., which means that sensory nerve deafferentation may be the most common pathophysiologic mechanism of neuropathic pain after SCI. Since in our study, we included short and discrete symptoms and signs based on diverse mechanisms, our results could be helpful for determining further evaluation and treatment.

  20. Neuropathic orofacial pain: Facts and fiction.

    Science.gov (United States)

    Baad-Hansen, Lene; Benoliel, Rafael

    2017-06-01

    Definition and taxonomy This review deals with neuropathic pain of traumatic origin affecting the trigeminal nerve, i.e. painful post-traumatic trigeminal neuropathy (PTTN). Symptomatology The clinical characteristics of PTTN vary considerably, partly due to the type and extent of injury. Symptoms involve combinations of spontaneous and evoked pain and of positive and negative somatosensory signs. These patients are at risk of going through unnecessary dental/surgical procedures in the attempt to eradicate the cause of the pain, due to the fact that most dentists only rarely encounter PTTN. Epidemiology Overall, approximately 3% of patients with trigeminal nerve injuries develop PTTN. Patients are most often female above the age of 45 years, and both physical and psychological comorbidities are common. Pathophysiology PTTN shares many pathophysiological mechanisms with other peripheral neuropathic pain conditions. Diagnostic considerations PTTN may be confused with one of the regional neuralgias or other orofacial pain conditions. For intraoral PTTN, early stages are often misdiagnosed as odontogenic pain. Pain management Management of PTTN generally follows recommendations for peripheral neuropathic pain. Expert opinion International consensus on classification and taxonomy is urgently needed in order to advance the field related to this condition.

  1. Spinal cord stimulation for neuropathic pain: current perspectives

    OpenAIRE

    Wolter, Tilman

    2014-01-01

    Tilman Wolter Interdisciplinary Pain Centre, University Hospital Freiburg, Freiburg, Germany Abstract: Neuropathic pain constitutes a significant portion of chronic pain. Patients with neuropathic pain are usually more heavily burdened than patients with nociceptive pain. They suffer more often from insomnia, anxiety, and depression. Moreover, analgesic medication often has an insufficient effect on neuropathic pain. Spinal cord stimulation constitutes a therapy alternative that, to date, re...

  2. Low-dose vaporized cannabis significantly improves neuropathic pain.

    Science.gov (United States)

    Wilsey, Barth; Marcotte, Thomas; Deutsch, Reena; Gouaux, Ben; Sakai, Staci; Donaghe, Haylee

    2013-02-01

    We conducted a double-blind, placebo-controlled, crossover study evaluating the analgesic efficacy of vaporized cannabis in subjects, the majority of whom were experiencing neuropathic pain despite traditional treatment. Thirty-nine patients with central and peripheral neuropathic pain underwent a standardized procedure for inhaling medium-dose (3.53%), low-dose (1.29%), or placebo cannabis with the primary outcome being visual analog scale pain intensity. Psychoactive side effects and neuropsychological performance were also evaluated. Mixed-effects regression models demonstrated an analgesic response to vaporized cannabis. There was no significant difference between the 2 active dose groups' results (P > .7). The number needed to treat (NNT) to achieve 30% pain reduction was 3.2 for placebo versus low-dose, 2.9 for placebo versus medium-dose, and 25 for medium- versus low-dose. As these NNTs are comparable to those of traditional neuropathic pain medications, cannabis has analgesic efficacy with the low dose being as effective a pain reliever as the medium dose. Psychoactive effects were minimal and well tolerated, and neuropsychological effects were of limited duration and readily reversible within 1 to 2 hours. Vaporized cannabis, even at low doses, may present an effective option for patients with treatment-resistant neuropathic pain. The analgesia obtained from a low dose of delta-9-tetrahydrocannabinol (1.29%) in patients, most of whom were experiencing neuropathic pain despite conventional treatments, is a clinically significant outcome. In general, the effect sizes on cognitive testing were consistent with this minimal dose. As a result, one might not anticipate a significant impact on daily functioning. Published by Elsevier Inc.

  3. Neuropathic Pain Following Spinal Cord Injury: Mechanism, Assessment and Treatment

    Directory of Open Access Journals (Sweden)

    Gul Mete Civelek

    2016-04-01

    Full Text Available Spinal cord injury (SCI is a devastating disease which may cause physical, psychological and social dysfunction. Neuropathic pain (NP after SCI is common, can be seen in varying degrees and is one of the most difficultly treated problems developing after SCI. With the addition of the NP to loss of function after SCI, sleep patterns, moods and daily activities of patients are adversely affected. In order to treat pain effectively, classification of pain after SCI must be done carefully and correctly. According to classification of International Pain Study Group, pain after SCI is divided into two main groups as nociceptive and neuropathic pain. Neuropathic pain is defined as %u201Cpain occuring as a direct result of a disease or lesion directly affecting somato-sensorial system%u201D. NP after SCI can be classified according to anatomical region (above the level of lesion, at the level of lesion, below the level of lesion. Treatment of NP after SCI is often challenging and receiving response to treatment may take long time. Therefore, treatment of NP after SCI should be multifactorial. Treatment options include pharmochologic treatment, application of transcutanous electrical nerve stimulation, psychiatric treatment approaches, and surgical approaches in selected cases. In pharmachologic treatment, first line agents are tricyclic antidepresants, pregabalin and gabapentin. In this review, mechanisms and assessment and treatment of NP after SCI is discussed with the guide of current literature.

  4. Neuropathic pain and cytokines: current perspectives

    Directory of Open Access Journals (Sweden)

    Clark AK

    2013-11-01

    Full Text Available Anna K Clark, Elizabeth A Old, Marzia Malcangio Wolfson Centre for Age Related Diseases, King's College London, London, UK Abstract: Neuropathic pain represents a major problem in clinical medicine because it causes debilitating suffering and is largely resistant to currently available analgesics. A characteristic of neuropathic pain is abnormal response to somatic sensory stimulation. Thus, patients suffering peripheral neuropathies may experience pain caused by stimuli which are normally nonpainful, such as simple touching of the skin or by changes in temperature, as well as exaggerated responses to noxious stimuli. Convincing evidence suggests that this hypersensitivity is the result of pain remaining centralized. In particular, at the first pain synapse in the dorsal horn of the spinal cord, the gain of neurons is increased and neurons begin to be activated by innocuous inputs. In recent years, it has become appreciated that a remote damage in the peripheral nervous system results in neuronal plasticity and changes in microglial and astrocyte activity, as well as infiltration of macrophages and T cells, which all contribute to central sensitization. Specifically, the release of pronociceptive factors such as cytokines and chemokines from neurons and non-neuronal cells can sensitize neurons of the first pain synapse. In this article we review the current evidence for the role of cytokines in mediating spinal neuron–non-neuronal cell communication in neuropathic pain mechanisms following peripheral nerve injury. Specific and selective control of cytokine-mediated neuronal–glia interactions results in attenuation of the hypersensitivity to both noxious and innocuous stimuli observed in neuropathic pain models, and may represent an avenue for future therapeutic intervention. Keywords: anti-inflammatory cytokines, proinflammatory cytokines, microglia, astrocytes, first pain synapse

  5. The evidence for pharmacological treatment of neuropathic pain

    DEFF Research Database (Denmark)

    Finnerup, Nanna Brix; Sindrup, Søren Hein; Jensen, Troels Staehelin

    2010-01-01

    to compare the efficacy and safety of different treatments for a number of neuropathic pain conditions. One hundred and seventy-four studies were included, representing a 66% increase in published randomized, placebo-controlled trials in the last 5 years. Painful poly-neuropathy (most often due to diabetes......Randomized, double-blind, placebo-controlled trials on neuropathic pain treatment are accumulating, so an updated review of the available evidence is needed. Studies were identified using MEDLINE and EMBASE searches. Numbers needed to treat (NNT) and numbers needed to harm (NNH) values were used......) was examined in 69 studies, postherpetic neuralgia in 23, while peripheral nerve injury, central pain, HIV neuropathy, and trigeminal neuralgia were less often studied. Tricyclic antidepressants, serotonin noradrenaline reuptake inhibitors, the anticonvulsants gabapentin and pregabalin, and opioids...

  6. Spinal cord stimulation for neuropathic pain: current perspectives.

    Science.gov (United States)

    Wolter, Tilman

    2014-01-01

    Neuropathic pain constitutes a significant portion of chronic pain. Patients with neuropathic pain are usually more heavily burdened than patients with nociceptive pain. They suffer more often from insomnia, anxiety, and depression. Moreover, analgesic medication often has an insufficient effect on neuropathic pain. Spinal cord stimulation constitutes a therapy alternative that, to date, remains underused. In the last 10 to 15 years, it has undergone constant technical advancement. This review gives an overview of the present practice of spinal cord stimulation for chronic neuropathic pain and current developments such as high-frequency stimulation and peripheral nerve field stimulation.

  7. Pharmacological treatment of diabetic neuropathic pain.

    Science.gov (United States)

    Smith, Howard S; Argoff, Charles E

    2011-03-26

    Neuropathic pain continues to be a difficult and challenging clinical issue to deal with effectively. Painful diabetic polyneuropathy is a complex pain condition that occurs with reasonable frequency in the population and it may be extremely difficult for clinicians to provide patients with effective analgesia. Chronic neuropathic pain may occur in approximately one of every four diabetic patients. The pain may be described as burning or a deep-seated ache with sporadic paroxysms of lancinating painful exacerbations. The pain is often constant, moderate to severe in intensity, usually primarily involves the feet and generally tends to worsen at night. Treatment may be multimodal but largely involves pharmacological approaches. Pharmacological therapeutic options include antidepressants (tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors), α2δ ligands and topical (5%) lidocaine patch. Other agents may be different antiepileptic drugs (carbamazepine, lamotrigine, topiramate), topical capsaicin, tramadol and other opioids. Progress continues with respect to understanding various mechanisms that may contribute to painful diabetic neuropathy. Agents that may hold some promise include neurotrophic factors, growth factors, immunomodulators, gene therapy and poly (adenosine diphosphate-ribose) polymerase inhibitors. It is hoped that in the future clinicians will be able to assess patient pathophysiology, which may help them to match optimal therapeutic agents to target individual patient aberrant mechanisms.

  8. Gabapentin for chronic neuropathic pain and fibromyalgia in adults.

    Science.gov (United States)

    Moore, R Andrew; Wiffen, Philip J; Derry, Sheena; Toelle, Thomas; Rice, Andrew S C

    2014-04-27

    This review is an update of a review published in 2011, itself a major update of previous reviews published in 2005 and 2000, investigating the effects of gabapentin in chronic neuropathic pain (pain due to nerve damage). Antiepileptic drugs are used to manage chronic neuropathic pain and fibromyalgia. To assess the analgesic efficacy and adverse effects of gabapentin in chronic neuropathic pain and fibromyalgia. We identified randomised trials of gabapentin for chronic neuropathic pain or fibromyalgia by searching the databases MEDLINE (1966 to March 2014), EMBASE (1980 to 2014 week 10), and CENTRAL in The Cochrane Library (Issue 3 of 12, 2014). We obtained clinical trial reports and synopses of published and unpublished studies from Internet sources, and searched Clinicaltrials.gov. Searches were run originally in 2011 and the date of the most recent search was 17 March 2014. Randomised, double-blind studies reporting the analgesic and adverse effects of gabapentin in neuropathic pain or fibromyalgia with assessment of pain intensity, pain relief, or both, using validated scales. Participants were adults. Three review authors independently extracted efficacy and adverse event data, examined issues of study quality, and assessed risk of bias. We performed analysis using three tiers of evidence. First tier evidence derived from data meeting current best standards and subject to minimal risk of bias (outcome equivalent to substantial pain intensity reduction, intention-to-treat analysis without imputation for dropouts; at least 200 participants in the comparison, 8 to 12 weeks duration, parallel design), second tier from data that failed to meet one or more of these criteria and were considered at some risk of bias but with adequate numbers in the comparison, and third tier from data involving small numbers of participants that were considered very likely to be biased or used outcomes of limited clinical utility, or both.For efficacy, we calculated the number needed

  9. Walking with Neuropathic Pain: Paradoxical Shift from Burden to Support?

    Directory of Open Access Journals (Sweden)

    David J. Kopsky

    2015-01-01

    Full Text Available Baclofen 5% cream can be used for the treatment of neuropathic pain. We describe an unusual case of a neuropathic pain patient with spinal cord injury. A 71-year-old woman with a partial spinal cord injury lesion at L4 complained of tingling, pins and needles, and burning in her legs. She scored her pain as 6 before adding baclofen 5% cream to her pain medication (pregabalin 450 mg, acetaminophen 3000 mg, and diclofenac 150 mg daily. One month later she experienced complete pain relief, though experienced increased difficulties in walking, leading to frequent falls. Her steadier walking without stumbling and falling was more important to her than pain reduction. Thus she decided to stop using baclofen. This unusual case report discusses two important issues that relate to pain medicine and rehabilitation in patients with painful spinal cord lesions: (1 the presence of wide areas of sensory loss “covered” by the presence of painful sensations and (2 pathological sensations that can be used and integrated in the body schema to create an improved spatiovisual orientation and thus mobility. Both these aspects have to be taken into account when treating pain and design rehabilitation programs.

  10. [Systematic review of safeness and therapeutic efficacy of cannabis in patients with multiple sclerosis, neuropathic pain, and in oncological patients treated with chemotherapy].

    Science.gov (United States)

    Amato, Laura; Minozzi, Silvia; Mitrova, Zuzana; Parmelli, Elena; Saulle, Rosella; Cruciani, Fabio; Vecchi, Simona; Davoli, Marina

    2017-01-01

    medical cannabis refers to the use of cannabis or cannabinoids as medical therapy to treat disease or alleviate symptoms. In the United States, 23 states and Washington DC (May 2015) have introduced laws to permit the medical use of cannabis. Within the European Union, medicinal cannabis laws and praxis vary wildly between Countries. to provide evidence for benefits and harms of cannabis (including extracts and tinctures) treatment for adults in the following indications: control of spasticity and pain in patients with multiple sclerosis; control of pain in patients with chronic neuropathic pain; control of nausea and vomiting in adults with cancer receiving chemotherapy. we searched the Cochrane Central Register of Controlled Trials, PubMed, and EMBASE from inception to September 2016. We also searched for on-going studies via ClinicalTrials.gov and the World Health Organization and International Clinical Trials Registry Platform (ICTRP) search portal. All searches included also non-English language literature. All relevant randomized controlled trials (RCTs) evaluating the safety and efficacy of cannabis (including extracts and tinctures) compared with placebo or other pharmacological agents were included. Three authors independently evaluated the titles and abstracts of studies identified in the literature searches for their eligibility. For studies considered eligible, we retrieved full texts. Three investigators independently extracted data. For the assessment of the quality of evidence, we used the standard methodological procedures recommended by Cochrane and GRADE working Group. 41 trials (4,550 participants) were included; 15 studies considered efficacy and safety of cannabis for patients with multiple sclerosis, 12 for patients with chronic pain, and 14 for patients with cancer receiving chemotherapy. The included studies were published between 1975 and 2015, and the majority of them were conducted in Europe. We judged almost 50% of these studies to be at

  11. EFNS guidelines on neurostimulation therapy for neuropathic pain

    DEFF Research Database (Denmark)

    EFNS Panel on Neuropathic Pain, Vienna; Cruccu, Giorgio; Aziz, T. Z.

    2007-01-01

    Pharmacological relief of neuropathic pain is often insufficient. Electrical neurostimulation is efficacious in chronic neuropathic pain and other neurological diseases. European Federation of Neurological Societies (EFNS) launched a Task Force to evaluate the evidence for these techniques...... and to produce relevant recommendations. We searched the literature from 1968 to 2006, looking for neurostimulation in neuropathic pain conditions, and classified the trials according to the EFNS scheme of evidence for therapeutic interventions. Spinal cord stimulation (SCS) is efficacious in failed back surgery...

  12. Spinal cord stimulation for neuropathic pain: current perspectives

    Directory of Open Access Journals (Sweden)

    Wolter T

    2014-11-01

    Full Text Available Tilman Wolter Interdisciplinary Pain Centre, University Hospital Freiburg, Freiburg, Germany Abstract: Neuropathic pain constitutes a significant portion of chronic pain. Patients with neuropathic pain are usually more heavily burdened than patients with nociceptive pain. They suffer more often from insomnia, anxiety, and depression. Moreover, analgesic medication often has an insufficient effect on neuropathic pain. Spinal cord stimulation constitutes a therapy alternative that, to date, remains underused. In the last 10 to 15 years, it has undergone constant technical advancement. This review gives an overview of the present practice of spinal cord stimulation for chronic neuropathic pain and current developments such as high-frequency stimulation and peripheral nerve field stimulation. Keywords: spinal cord stimulation, neuropathic pain, neurostimulation

  13. Neuropathic pain: is quantitative sensory testing helpful?

    Science.gov (United States)

    Krumova, Elena K; Geber, Christian; Westermann, Andrea; Maier, Christoph

    2012-08-01

    Neuropathic pain arises as a consequence of a lesion or disease affecting the somatosensory system and is characterised by a combination of positive and negative sensory symptoms. Quantitative sensory testing (QST) examines the sensory perception after application of different mechanical and thermal stimuli of controlled intensity and the function of both large (A-beta) and small (A-delta and C) nerve fibres, including the corresponding central pathways. QST can be used to determine detection, pain thresholds and stimulus-response curves and can thus detect both negative and positive sensory signs, the second ones not being assessed by other methods. Similarly to all other psychophysical tests QST requires standardised examination, instructions and data evaluation to receive valid and reliable results. Since normative data are available, QST can contribute also to the individual diagnosis of neuropathy, especially in the case of isolated small-fibre neuropathy, in contrast to the conventional electrophysiology which assesses only large myelinated fibres. For example, detection of early stages of subclinical neuropathy in symptomatic or asymptomatic patients with diabetes mellitus can be helpful to optimise treatment and identify diabetic foot at risk of ulceration. QST assessed the individual's sensory profile and thus can be valuable to evaluate the underlying pain mechanisms which occur in different frequencies even in the same neuropathic pain syndromes. Furthermore, assessing the exact sensory phenotype by QST might be useful in the future to identify responders to certain treatments in accordance to the underlying pain mechanisms.

  14. Neuropathic sensory symptoms: association with pain and psychological factors

    Directory of Open Access Journals (Sweden)

    Shaygan M

    2014-05-01

    Full Text Available Maryam Shaygan,1 Andreas Böger,2 Birgit Kröner-Herwig11Department of Clinical Psychology and Psychotherapy, University of Göttingen, Germany; 2Pain Management Clinic at the Red Cross Hospital, Kassel, GermanyBackground: A large number of population-based studies of chronic pain have considered neuropathic sensory symptoms to be associated with a high level of pain intensity and negative affectivity. The present study examines the question of whether this association previously found in non-selected samples of chronic pain patients can also be found in chronic pain patients with underlying pathology of neuropathic sensory symptoms.Methods: Neuropathic sensory symptoms in 306 patients with chronic pain diagnosed as typical neuropathic pain, radiculopathy, fibromyalgia, or nociceptive back pain were assessed using the Pain DETECT Questionnaire. Two separate cluster analyses were performed to identify subgroups of patients with different levels of self-reported neuropathic sensory symptoms and, furthermore, to identify subgroups of patients with distinct patterns of neuropathic sensory symptoms (adjusted for individual response bias regarding specific symptoms.Results: ANOVA (analysis of variance results in typical neuropathic pain, radiculopathy, and fibromyalgia showed no significant differences between the three levels of neuropathic sensory symptoms regarding pain intensity, pain chronicity, pain catastrophizing, pain acceptance, and depressive symptoms. However, in nociceptive back pain patients, significant differences were found for all variables except pain chronicity. When controlling for the response bias of patients in ratings of symptoms, none of the patterns of neuropathic sensory symptoms were associated with pain and psychological factors.Conclusion: Neuropathic sensory symptoms are not closely associated with higher levels of pain intensity and cognitive-emotional evaluations in chronic pain patients with underlying pathology of

  15. Neuropathic pain due to fibromatosis: Does anticancer treatment help?

    Directory of Open Access Journals (Sweden)

    David Mathew

    2011-01-01

    Full Text Available Desmoid fibromatosis, although histologically benign, infiltrates local structures. The involvement of neural structures can lead to difficult neuropathic pain and the escalating use of analgesics. We report a patient with desmoid fibromatosis of the chest wall causing brachial plexus infiltration. As the tumor was locally invasive and unresectable, he was treated with radiation therapy and oral tamoxifen. On follow-up, there was significant pain relief, sustained reduction in the tumor size, and reduced analgesic requirement. Antineoplastic treatments like local radiation therapy and targeted systemic therapy with hormones or other agents can be considered in the management of selected unresectable desmoid fibromatosis to improve symptom control and reduce polypharmacy.

  16. Diagnosis and medical treatment of neuropathic pain in leprosy.

    Science.gov (United States)

    Arco, Rogerio Del; Nardi, Susilene Maria Tonelli; Bassi, Thiago Gasperini; Paschoal, Vania Del Arco

    2016-08-08

    to identify the difficulties in diagnosing and treating neuropathic pain caused by leprosy and to understand the main characteristics of this situation. 85 patients were treated in outpatient units with reference to leprosy and the accompanying pain. We used a questionnaire known as the Douleur Neuropathic 4 test and we conducted detailed neurological exams. As a result, 42 patients were excluded from the study for not having proved their pain. Out of the 37 patients that experienced pain, 22 (59.5%) had neuropathic pain (or a mixture of this pain and their existing pain) and of these 90.8% considered this pain to be moderate or severe. 81.8% of the sample suffered with this pain for more than 6 months. Only 12 (54.5%) of the patients had been diagnosed with neuropathic pain and in almost half of these cases, this pain had not been diagnosed. With reference to medical treatment (n=12) for neuropathic pain, 5 (41.6%) responded that they became better. For the other 7 (58.4%) there were no changes in relation to the pain or in some cases the pain worsened in comparison to their previous state. Statistical analysis comparing improvements in relation to the pain amongst the patients that were treated (n=12) and those that were not, showed significant differences (value p=0.020). we noted difficulties in diagnosing neuropathic pain for leprosy in that almost half of the patients that were studied had not had their pain diagnosed. We attributed this to some factors such as the non-adoption of the appropriate protocols which led to inadequate diagnosis and treatment that overlooked the true picture. identificar as dificuldades em diagnosticar e tratar a dor neuropática causada pela hanseníase, bem como determinar as características principais dessa situação. examinaram-se 85 pacientes tratados no ambulatório de referência para hanseníase e referiam dor. Aplicou-se questionário, o teste Douleur Neuropathic 4, e criterioso exame neurológico pelo qual exclu

  17. Phenytoin Cream for the Treatment of Neuropathic Pain: Case Series

    Directory of Open Access Journals (Sweden)

    David J. Kopsky

    2018-05-01

    Full Text Available BACKGROUND: Neuropathic pain can be disabling, and is often difficult to treat. Within a year, over half of all patients stop taking their prescribed neuropathic pain medication, which is most probably due to side effects or disappointing analgesic results. Therefore, new therapies are needed to alleviate neuropathic pain. As such, topical analgesics could be a new inroad in the treatment of neuropathic pain. In 2014, we developed a new topical formulation containing either phenytoin or sodium phenytoin. After optimization of the formulation, we were able to reach a 10% concentration and combine phenytoin with other co-analgesics in the same base cream. OBJECTIVE: To describe a series of 70 neuropathic pain patients who were treated with phenytoin cream. MATERIAL AND METHODS: Cases treated with phenytoin 5% or 10% creams were gathered. The mean onset of pain relief, the duration of effect, and reduction in pain intensity measured on the 11-point numerical rating scale (NRS were all studied. A single-blind response test with phenytoin 10% and placebo creams was conducted on 12 patients in order to select responders prior to prescribing the active cream. Plasma phenytoin concentrations were measured in 16 patients. RESULTS: Nine patients applied phenytoin 5% cream, and 61 patients used phenytoin 10% cream. After grouping the effects of all of the patients, the mean onset of pain relief was 16.3 min (SD: 14.8, the mean duration of analgesia was 8.1 h (SD: 9.1, and the mean pain reduction on the NRS was 61.2% (SD: 25.0. The mean pain reduction on the NRS while using phenytoin cream was statistically significant compared with the baseline, with a reduction of 4.5 (CI: 4.0 to 5.0, p < 0.01. The 12 patients on whom a single-blind response test was performed experienced a statistically significant reduction in pain in the area where the phenytoin 10% cream was applied in comparison to the area where the placebo cream was applied (p < 0.01. Thirty

  18. NMDA receptor antagonists for the treatment of neuropathic pain

    NARCIS (Netherlands)

    Collins, S.; Sigtermans, M.J.; Dahan, A.; Zuurmond, W.W.A.; Perez, R.S.G.M.

    2010-01-01

    Objective. The N-methyl-D-Aspartate (NMDA) receptor has been proposed as a primary target for the treatment of neuropathic pain. The aim of the present study was to perform a meta-analysis evaluating the effects of (individual) NMDA receptor antagonists on neuropathic pain, and the response

  19. Neuropathic pain and use of PainDETECT in patients with fibromyalgia: a cohort study.

    Science.gov (United States)

    Gauffin, Jarno; Hankama, Tiina; Kautiainen, Hannu; Hannonen, Pekka; Haanpää, Maija

    2013-02-14

    Fibromyalgia has a plethorae of symptoms, which can be confusing and even misleading. Accurate evaluation is necessary when patients with fibromyalgia are treated. Different types of instruments are available for the clinicians to supplement evaluation. Our objective was to study the applicability of the PainDETECT instrument to screen neuropathic pain in patients with fibromyalgia. 158 patients with primary fibromyalgia underwent a neurological examination including bedside sensory testing. They also fulfilled four questionnaires: PainDETECT, Beck depression inventory IA (BDI IA), Fibromyalgia Impact Questionnaire (FIQ) and a self-made questionnaire regarding present pain and pain relieving methods of the patients. The results of the clinical evaluation and questionnaires were then compared. Clinically verified neuropathic pain was diagnosed in 53/158 [34% (95% Cl: 26 to 41)] patients. The ROC curve achieved a maximum Youden´s index at score of 17 when sensitivity was 0.79 (95% Cl: 0.66 to 0.89) and specificity 0.53 (95% Cl: 0.43 to 0.63). The PainDETECT total score (OR: 1.14 95% Cl: 1.06 to 1.22), FM as the worst current pain (OR: 0.31; 95% 0.16 to 0.62), body mass index (BMI) (OR: 1.05; 95% Cl: 1.00 to 1.11) and the intensity of current pain (OR: 1.20; 95% Cl: 1.01 to 1.41) were significantly associated with the presence of neuropathic pain in univariate analyses. This study highlights the importance of thorough clinical examination. The Neuropathic pain screening tool PainDETECT is not as useful in patients with fibromyalgia as in patients with uncompromised central pain control.

  20. Neuropathic pain and use of PainDETECT in patients with fibromyalgia: a cohort study

    Directory of Open Access Journals (Sweden)

    Gauffin Jarno

    2013-02-01

    Full Text Available Abstract Backround Fibromyalgia has a plethorae of symptoms, which can be confusing and even misleading. Accurate evaluation is necessary when patients with fibromyalgia are treated. Different types of instruments are available for the clinicians to supplement evaluation. Our objective was to study the applicability of the PainDETECT instrument to screen neuropathic pain in patients with fibromyalgia. Methods 158 patients with primary fibromyalgia underwent a neurological examination including bedside sensory testing. They also fulfilled four questionnaires: PainDETECT, Beck depression inventory IA (BDI IA, Fibromyalgia Impact Questionnaire (FIQ and a self-made questionnaire regarding present pain and pain relieving methods of the patients. The results of the clinical evaluation and questionnaires were then compared. Results Clinically verified neuropathic pain was diagnosed in 53/158 [34% (95% Cl: 26 to 41] patients. The ROC curve achieved a maximum Youden´s index at score of 17 when sensitivity was 0.79 (95% Cl: 0.66 to 0.89 and specificity 0.53 (95% Cl: 0.43 to 0.63. The PainDETECT total score (OR: 1.14 95% Cl: 1.06 to 1.22, FM as the worst current pain (OR: 0.31; 95% 0.16 to 0.62, body mass index (BMI (OR: 1.05; 95% Cl: 1.00 to 1.11 and the intensity of current pain (OR: 1.20; 95% Cl: 1.01 to 1.41 were significantly associated with the presence of neuropathic pain in univariate analyses. Conclusion This study highlights the importance of thorough clinical examination. The Neuropathic pain screening tool PainDETECT is not as useful in patients with fibromyalgia as in patients with uncompromised central pain control.

  1. An Algorithm for Neuropathic Pain Management in Older People.

    Science.gov (United States)

    Pickering, Gisèle; Marcoux, Margaux; Chapiro, Sylvie; David, Laurence; Rat, Patrice; Michel, Micheline; Bertrand, Isabelle; Voute, Marion; Wary, Bernard

    2016-08-01

    Neuropathic pain frequently affects older people, who generally also have several comorbidities. Elderly patients are often poly-medicated, which increases the risk of drug-drug interactions. These patients, especially those with cognitive problems, may also have restricted communication skills, making pain evaluation difficult and pain treatment challenging. Clinicians and other healthcare providers need a decisional algorithm to optimize the recognition and management of neuropathic pain. We present a decisional algorithm developed by a multidisciplinary group of experts, which focuses on pain assessment and therapeutic options for the management of neuropathic pain, particularly in the elderly. The algorithm involves four main steps: (1) detection, (2) evaluation, (3) treatment, and (4) re-evaluation. The detection of neuropathic pain is an essential step in ensuring successful management. The extent of the impact of the neuropathic pain is then assessed, generally with self-report scales, except in patients with communication difficulties who can be assessed using behavioral scales. The management of neuropathic pain frequently requires combination treatments, and recommended treatments should be prescribed with caution in these elderly patients, taking into consideration their comorbidities and potential drug-drug interactions and adverse events. This algorithm can be used in the management of neuropathic pain in the elderly to ensure timely and adequate treatment by a multidisciplinary team.

  2. Prevalence of Neuropathic Pain and the Need for Treatment

    Directory of Open Access Journals (Sweden)

    Pat Morley-Forster

    2006-01-01

    There is an unmet need for the treatment of neuropathic pain as evidenced by reports of pain despite the use of opioids and anticonvulsants, continuing psychological difficulties, lack of access to treatments and patients seeking access to complementary therapy.

  3. Tramadol and propentofylline coadministration exerted synergistic effects on rat spinal nerve ligation-induced neuropathic pain.

    Science.gov (United States)

    Zhang, Jin; Wu, Dan; Xie, Cheng; Wang, Huan; Wang, Wei; Zhang, Hui; Liu, Rui; Xu, Li-Xian; Mei, Xiao-Peng

    2013-01-01

    Neuropathic pain is an intractable clinical problem. Drug treatments such as tramadol have been reported to effectively decrease neuropathic pain by inhibiting the activity of nociceptive neurons. It has also been reported that modulating glial activation could also prevent or reverse neuropathic pain via the administration of a glial modulator or inhibitor, such as propentofylline. Thus far, there has been no clinical strategy incorporating both neuronal and glial participation for treating neuropathic pain. Therefore, the present research study was designed to assess whether coadministration of tramadol and propentofylline, as neuronal and glial activation inhibitors, respectively, would exert a synergistic effect on the reduction of rat spinal nerve ligation (SNL)-induced neuropathic pain. Rats underwent SNL surgery to induce neuropathic pain. Pain behavioral tests were conducted to ascertain the effect of drugs on SNL-induced mechanical allodynia with von-Frey hairs. Proinflammatory factor interleukin-1β (IL-1β) expression was also detected by Real-time RT-PCR. Intrathecal tramadol and propentofylline administered alone relieved SNL-induced mechanical allodynia in a dose-dependent manner. Tramadol and propentofylline coadministration exerted a more potent effect in a synergistic and dose dependent manner than the intrathecal administration of either drug alone. Real-time RT-PCR demonstrated IL-1β up-expression in the ipsilateral spinal dorsal horn after the lesion, which was significantly decreased by tramadol and propentofylline coadministration. Inhibiting proinflammatory factor IL-1β contributed to the synergistic effects of tramadol and propentofylline coadministration on rat peripheral nerve injury-induced neuropathic pain. Thus, our study provided a rationale for utilizing a novel strategy for treating neuropathic pain by blocking the proinflammatory factor related pathways in the central nervous system.

  4. Neuropathic pain and use of PainDETECT in patients with fibromyalgia: a cohort study

    OpenAIRE

    Gauffin, Jarno; Hankama, Tiina; Kautiainen, Hannu; Hannonen, Pekka; Haanp??, Maija

    2013-01-01

    Abstract Backround Fibromyalgia has a plethorae of symptoms, which can be confusing and even misleading. Accurate evaluation is necessary when patients with fibromyalgia are treated. Different types of instruments are available for the clinicians to supplement evaluation. Our objective was to study the applicability of the PainDETECT instrument to screen neuropathic pain in patients with fibromyalgia. Methods 158 patients with primary fibromyalgia underwent a neurological examination includin...

  5. An Algorithm for Neuropathic Pain Management in Older People

    OpenAIRE

    Pickering, Gis?le; Marcoux, Margaux; Chapiro, Sylvie; David, Laurence; Rat, Patrice; Michel, Micheline; Bertrand, Isabelle; Voute, Marion; Wary, Bernard

    2016-01-01

    Neuropathic pain frequently affects older people, who generally also have several comorbidities. Elderly patients are often poly-medicated, which increases the risk of drug?drug interactions. These patients, especially those with cognitive problems, may also have restricted communication skills, making pain evaluation difficult and pain treatment challenging. Clinicians and other healthcare providers need a decisional algorithm to optimize the recognition and management of neuropathic pain. W...

  6. Effects of fisetin on oxaliplatin-induced neuropathic pain in mice

    Directory of Open Access Journals (Sweden)

    Hong Liu

    2015-03-01

    Full Text Available Common chemotherapeutic agents such as oxaliplatin often cause neuropathic pain during cancer treatment in patients. Such neuropathic pain is difficult to treat and responds poorly to common analgesics, which represents a challenging clinical issue. Fisetin is a naturally occurring flavonoid and this study tested the potential anti-hyperalgesic effects of fisetin in a mice model of oxaliplatin-induced neuropathic pain. Fisetin (1-4 mg/kg, i.p. did not significantly alter the mechanical hypersensitivity in oxaliplatin-treated mice but produced a dose-dependent anti-hyperalgesic effect during repeated treatment. Repeated treatment with fisetin also prevented chronic neuropathic pain-induced depressive-like behavior in a forced swimming test. Both the antihyperalgesic and the antidepressant-like effects of fisetin can be blocked by a selective 5-HT1A receptor antagonist WAY100635 (1 mg/kg. Together, these results demonstrate that fisetin has significant analgesic efficacy against chronic neuropathic pain, which could be a useful analgesic in the management of neuropathic pain.

  7. [Preoperative, neuropathic component in patients with back pain].

    Science.gov (United States)

    Lee, Y-J; Koch, E M W; Breidebach, J B; Bornemann, R; Wirtz, D C; Pflugmacher, R

    2017-04-01

    The objectification of pain is essential for evaluation, treatment plan and follow-up; therefore, it is necessary to find reliable clinical parameters. The goal of the study was the preoperative screening of a neuropathic component in patients with vertebral compression fracture (WKF), herniated disc (NPP) or spinal cord compression (SKS). Depending on the preoperative condition on admittance, patients were classified into three groups: group 1 WKF, group 2 NPP and group 3 SKS. To characterize the pain we used the painDETECT questionnaire, the Oswestry questionnaire and further questionnaires. All patients were surgically treated according to the diagnosis, e.g. radiofrequency kyphoplasty, nucleotomy or spondylodesis. We evaluated the data from 139 patients (45% WKF, 34% NPP and 21% SKS). There were no differences in preoperative pain intensity (median ordinal scale 0-10) with a mean preoperative score of 7 for all groups. The total score of the painDETECT questionnaire showed significantly higher results in group 2 (median 18) and in group 3 (median 14) than in group 1 (median 9). There was even a significant difference between groups 2 and 3 (p = 0.03). The highest pain intensity was detected in group 1 with a median visual analog scale (VAS) of 71 mm. The total scores in the painDETECT questionnaire and the scores in the Oswestry questionnaire correlated in groups 2 and 3. The painDETECT questionnaire was shown to be a very suitable instrument for evaluating the neuropathic pain component in patients with dorsalgia. This could be very useful in planning further therapy.

  8. Chronic Neuropathic Pain in Spinal Cord Injury: The Patient's Perspective

    Directory of Open Access Journals (Sweden)

    Penelope Henwood

    2004-01-01

    Full Text Available BACKGROUND: Chronic neuropathic pain (CNP in spinal cord injury (SCI is recognized as severely compromising, in both adjustment after injury and quality of life. Studies indicate that chronic pain in SCI is associated with great emotional distress over and above that of the injury itself. Currently, little is known about the SCI patient's perception of the impact of living with chronic neuropathic pain.

  9. Clinical and economic consequences of treating patients with peripheral neuropathic pain with brand name or generic drugs in routine clinical practice: The effects of age and sex.

    Science.gov (United States)

    Navarro-Artieda, R; Rejas-Gutiérrez, J; Pérez-Paramo, M; Sicras-Mainar, A

    2018-04-01

    We aimed to analyse the effects of age and sex on pain and cost for patients with chronic peripheral neuropathic pain (PNP) who have started treatment with brand name gabapentin versus generic gabapentin (EFG). We conducted a retrospective multicentre study using electronic medical records (EMR) for patients of both sexes, older than 18, who began treatment with brand name or generic gabapentin. Adherence (medication possession ratio [MPR]), persistence, use of healthcare resources, cost, and pain reduction were measured for one year. We analysed 1369 EMRs [61.1% women; mean age 64.6 (15.9), 52.4%≥65 years]; 400 used brand name drugs while 969 used generic gabapentin. Persistence and adherence were higher in patients using brand name gabapentin (7.3 vs 6.3 months, Pbrand-name gabapentin in both age groups (brand treatment showed greater pain relief: 13.5% (10.9-16.2) and 10.8% (8.2-13.5) in brand name medication showed greater persistence and adherence to treatment than those taking generic drugs. Brand name treatment also involved lower healthcare costs, and greater pain relief. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. Long term clinical outcome of peripheral nerve stimulation in patients with chronic peripheral neuropathic pain

    DEFF Research Database (Denmark)

    Calenbergh, F. Van; Gybels, J.; Laere, K. Van

    2009-01-01

    BACKGROUND: Chronic neuropathic pain after injury to a peripheral nerve is known to be resistant to treatment. Peripheral nerve stimulation is one of the possible treatment options, which is, however, not performed frequently. In recent years we have witnessed a renewed interest for PNS. The aim...... of the present study was to evaluate the long-term clinical efficacy of PNS in a group of patients with peripheral neuropathic pain treated with PNS since the 1980s. METHODS: Of an original series of 11 patients, 5 patients could be invited for clinical examination, detailed assessment of clinical pain and QST...... functioning) also showed positive effects. Quantitative Sensory Testing results did not show significant differences in cold pain and heat pain thresholds between the "ON" and "OFF" conditions. CONCLUSION: In selected patients with peripheral neuropathic pain PNS remains effective even after more than 20...

  11. Combination of Tramadol with Minocycline Exerted Synergistic Effects on a Rat Model of Nerve Injury-Induced Neuropathic Pain

    Directory of Open Access Journals (Sweden)

    Xiao-Peng Mei

    2012-09-01

    Full Text Available Neuropathic pain is a refractory clinical problem. Certain drugs, such as tramadol, proved useful for the treatment of neuropathic pain by inhibiting the activity of nociceptive neurons. Moreover, studies indicated that suppression or modulation of glial activation could prevent or reverse neuropathic pain, for example with the microglia inhibitor minocycline. However, few present clinical therapeutics focused on both neuronal and glial participation when treating neuropathic pain. Therefore, the present study hypothesized that combination of tramadol with minocycline as neuronal and glial activation inhibitor may exert some synergistic effects on spinal nerve ligation (SNL-induced neuropathic pain. Intrathecal tramadol or minocycline relieved SNL-induced mechanical allodynia in a dose-dependent manner. SNL-induced spinal dorsal horn Fos or OX42 expression was downregulated by intrathecal tramadol or minocycline. Combination of tramadol with minocycline exerted powerful and synergistic effects on SNL-induced neuropathic pain also in a dose-dependent manner. Moreover, the drug combination enhanced the suppression effects on SNL-induced spinal dorsal horn Fos and OX42 expression, compared to either drug administered alone. These results indicated that combination of tramadol with minocycline could exert synergistic effects on peripheral nerve injury-induced neuropathic pain; thus, a new strategy for treating neuropathic pain by breaking the interaction between neurons and glia bilaterally was also proposed.

  12. Characterizing neuropathic pain profiles: enriching interpretation of painDETECT

    Directory of Open Access Journals (Sweden)

    Cappelleri JC

    2016-07-01

    Full Text Available Joseph C Cappelleri,1 Vijaya Koduru,2 E Jay Bienen,3 Alesia Sadosky4 1Pfizer Inc, Groton, CT, USA; 2Eliassen Group, New London, CT, USA; 3Outcomes Research Consultant, New York, NY, USA; 4Pfizer Inc, New York, NY, USA Purpose: To psychometrically evaluate painDETECT, a patient-reported screening questionnaire for neuropathic pain (NeP, for discriminating among sensory pain symptoms (burning, tingling/prickling, light touching, sudden pain attacks/electric shock-type pain, cold/heat, numbness, and slight pressure. Methods: The seven-item version of painDETECT provides an overall score that targets only sensory symptoms, while the nine-item version adds responses on two items to the overall score, covering pain course pattern and pain radiation. Both versions have relevance in terms of characterizing broad NeP. The nine- and seven-item versions of painDETECT were administered to subjects with confirmed NeP across six conditions identified during office visits to US community-based physicians. Responses on the sensory symptom items were dichotomized into “at least moderate” (ie, moderate, strongly, very strongly relative to the combined other responses (never, hardly noticed, slightly. Logistic regression of dichotomized variables on the total painDETECT score provided probabilities of experiencing each symptom across the range of painDETECT scores. Results: Both painDETECT versions discriminated among the symptoms with similar probabilities across the score ranges. Using these data, the probability of moderately experiencing each pain sensory item was estimated for a particular score, providing a pain profile. Additionally, the likelihood of experiencing each sensation was determined for a discrete increase in score, ie, the odds of at least a moderate sensation of burning (versus less than a moderate sensation was 1.29 for a 1-point increase, 3.52 for a 5-point increase, and 12.42 for every 10-point increase in the nine-item painDETECT score

  13. Can We Distinguish between Inflammatory and Neuropathic Pain?

    Directory of Open Access Journals (Sweden)

    Gary J Bennett

    2006-01-01

    Full Text Available Inflammatory and neuropathic pain were once considered to be distinct entities. However, research over the past decade or so has brought to light many shared mechanisms, and the distinction between the two is no longer clear. Consideration of mechanisms, symptoms and the effects of analgesic drugs does not reveal any definitive or universally applicable differentiating factors. Given the present level of understanding, it may not be possible to distinguish between inflammatory and neuropathic pain in a large number of patients, and a satisfying definition of neuropathic pain may not be possible.

  14. EFNS guidelines on neurostimulation therapy for neuropathic pain

    DEFF Research Database (Denmark)

    EFNS Panel on Neuropathic Pain, Vienna; Cruccu, Giorgio; Aziz, T. Z.

    2007-01-01

    and to produce relevant recommendations. We searched the literature from 1968 to 2006, looking for neurostimulation in neuropathic pain conditions, and classified the trials according to the EFNS scheme of evidence for therapeutic interventions. Spinal cord stimulation (SCS) is efficacious in failed back surgery......Pharmacological relief of neuropathic pain is often insufficient. Electrical neurostimulation is efficacious in chronic neuropathic pain and other neurological diseases. European Federation of Neurological Societies (EFNS) launched a Task Force to evaluate the evidence for these techniques......TMS) has transient efficacy in central and peripheral neuropathic pains (level B). Motor cortex stimulation (MCS) is efficacious in central post-stroke and facial pain (level C). Deep brain stimulation (DBS) should only be performed in experienced centres. Evidence for implanted peripheral stimulations...

  15. Descending volleys generated by efficacious epidural motor cortex stimulation in patients with chronic neuropathic pain

    NARCIS (Netherlands)

    Lefaucheur, Jean-Pascal; Holsheimer, J.; Goujon, Colette; Keravel, Yves; Nguyen, Jean-Paul

    Epidural motor cortex stimulation (EMCS) is a therapeutic option for chronic, drug-resistant neuropathic pain, but its mechanisms of action remain poorly understood. In two patients with refractory hand pain successfully treated by EMCS, the presence of implanted epidural cervical electrodes for

  16. Topical amitriptyline and ketamine for the treatment of neuropathic pain.

    Science.gov (United States)

    Mercadante, Sebastiano

    2015-01-01

    A neuropathy is a disturbance of function or pathological change in nerves. In some cases, peripheral neuropathic pain may occur due to a lesion or disease of the peripheral somatosensory nervous system. Efficacy of different agents for peripheral neuropathic pain conditions is less than optimal. The administration of topical analgesics might be an option, due to the potential of reduced adverse effects and increased patient compliance. There is major interest in compounding topical analgesics for peripheral neuropathic pain, but several challenges remain for this approach. Topical analgesics have the potential to be a valuable additional approach for the management of peripheral neuropathic pain. Topical amitriptyline-ketamine combination (AK) is a promising agent for peripheral neuropathic pain conditions. Some studies have shown its efficacy in neuropathic pain conditions. However, this data was not uniformely obtained and its role remains still controversial. Efficacy may depend on many factors, including the choice of the vehicle, the concentration, the pain site, and specific diseases. More studies are necessary to support the use of AK in clinical practice.

  17. Pharmacological Regulation of Neuropathic Pain Driven by Inflammatory Macrophages

    Directory of Open Access Journals (Sweden)

    Norikazu Kiguchi

    2017-11-01

    Full Text Available Neuropathic pain can have a major effect on quality of life but current therapies are often inadequate. Growing evidence suggests that neuropathic pain induced by nerve damage is caused by chronic inflammation. Upon nerve injury, damaged cells secrete pro-inflammatory molecules that activate cells in the surrounding tissue and recruit circulating leukocytes to the site of injury. Among these, the most abundant cell type is macrophages, which produce several key molecules involved in pain enhancement, including cytokines and chemokines. Given their central role in the regulation of peripheral sensitization, macrophage-derived cytokines and chemokines could be useful targets for the development of novel therapeutics. Inhibition of key pro-inflammatory cytokines and chemokines prevents neuroinflammation and neuropathic pain; moreover, recent studies have demonstrated the effectiveness of pharmacological inhibition of inflammatory (M1 macrophages. Nicotinic acetylcholine receptor ligands and T helper type 2 cytokines that reduce M1 macrophages are able to relieve neuropathic pain. Future translational studies in non-human primates will be crucial for determining the regulatory mechanisms underlying neuroinflammation-associated neuropathic pain. In turn, this knowledge will assist in the development of novel pharmacotherapies targeting macrophage-driven neuroinflammation for the treatment of intractable neuropathic pain.

  18. An Intensive Locomotor Training Paradigm Improves Neuropathic Pain following Spinal Cord Compression Injury in Rats.

    Science.gov (United States)

    Dugan, Elizabeth A; Sagen, Jacqueline

    2015-05-01

    Spinal cord injury (SCI) is often associated with both locomotor deficits and sensory dysfunction, including debilitating neuropathic pain. Unfortunately, current conventional pharmacological, physiological, or psychological treatments provide only marginal relief for more than two-thirds of patients, highlighting the need for improved treatment options. Locomotor training is often prescribed as an adjunct therapy for peripheral neuropathic pain but is rarely used to treat central neuropathic pain. The goal of this study was to evaluate the potential anti-nociceptive benefits of intensive locomotor training (ILT) on neuropathic pain consequent to traumatic SCI. Using a rodent SCI model for central neuropathic pain, ILT was initiated either 5 d after injury prior to development of neuropathic pain symptoms (the "prevention" group) or delayed until pain symptoms fully developed (∼3 weeks post-injury, the "reversal" group). The training protocol consisted of 5 d/week of a ramping protocol that started with 11 m/min for 5 min and increased in speed (+1 m/min/week) and time (1-4 minutes/week) to a maximum of two 20-min sessions/d at 15 m/min by the fourth week of training. ILT prevented and reversed the development of heat hyperalgesia and cold allodynia, as well as reversed developed tactile allodynia, suggesting analgesic benefits not seen with moderate levels of locomotor training. Further, the analgesic benefits of ILT persisted for several weeks once training had been stopped. The unique ability of an ILT protocol to produce robust and sustained anti-nociceptive effects, as assessed by three distinct outcome measures for below-level SCI neuropathic pain, suggests that this adjunct therapeutic approach has great promise in a comprehensive treatment strategy for SCI pain.

  19. Cannabis-based medicines for chronic neuropathic pain in adults.

    Science.gov (United States)

    Mücke, Martin; Phillips, Tudor; Radbruch, Lukas; Petzke, Frank; Häuser, Winfried

    2018-03-07

    This review is one of a series on drugs used to treat chronic neuropathic pain. Estimates of the population prevalence of chronic pain with neuropathic components range between 6% and 10%. Current pharmacological treatment options for neuropathic pain afford substantial benefit for only a few people, often with adverse effects that outweigh the benefits. There is a need to explore other treatment options, with different mechanisms of action for treatment of conditions with chronic neuropathic pain. Cannabis has been used for millennia to reduce pain. Herbal cannabis is currently strongly promoted by some patients and their advocates to treat any type of chronic pain. To assess the efficacy, tolerability, and safety of cannabis-based medicines (herbal, plant-derived, synthetic) compared to placebo or conventional drugs for conditions with chronic neuropathic pain in adults. In November 2017 we searched CENTRAL, MEDLINE, Embase, and two trials registries for published and ongoing trials, and examined the reference lists of reviewed articles. We selected randomised, double-blind controlled trials of medical cannabis, plant-derived and synthetic cannabis-based medicines against placebo or any other active treatment of conditions with chronic neuropathic pain in adults, with a treatment duration of at least two weeks and at least 10 participants per treatment arm. Three review authors independently extracted data of study characteristics and outcomes of efficacy, tolerability and safety, examined issues of study quality, and assessed risk of bias. We resolved discrepancies by discussion. For efficacy, we calculated the number needed to treat for an additional beneficial outcome (NNTB) for pain relief of 30% and 50% or greater, patient's global impression to be much or very much improved, dropout rates due to lack of efficacy, and the standardised mean differences for pain intensity, sleep problems, health-related quality of life (HRQoL), and psychological distress. For

  20. [Transcranial magnetic stimulation and motor cortex stimulation in neuropathic pain].

    Science.gov (United States)

    Mylius, V; Ayache, S S; Teepker, M; Kappus, C; Kolodziej, M; Rosenow, F; Nimsky, C; Oertel, W H; Lefaucheur, J P

    2012-12-01

    Non-invasive and invasive cortical stimulation allows the modulation of therapy-refractory neuropathic pain. High-frequency repetitive transcranial magnetic stimulation (rTMS) of the contralateral motor cortex yields therapeutic effects at short-term and predicts the benefits of epidural motor cortex stimulation (MCS). The present article summarizes the findings on application, mechanisms and therapeutic effects of cortical stimulation in neuropathic pain.

  1. Intravenous Ketamine Infusions for Neuropathic Pain Management: A Promising Therapy in Need of Optimization.

    Science.gov (United States)

    Maher, Dermot P; Chen, Lucy; Mao, Jianren

    2017-02-01

    Intravenous ketamine infusions have been used extensively to treat often-intractable neuropathic pain conditions. Because there are many widely divergent ketamine infusion protocols described in the literature, the variation in these protocols presents a challenge for direct comparison of one protocol with another and in discerning an optimal protocol. Careful examination of the published literature suggests that ketamine infusions can be useful to treat neuropathic pain and that certain characteristics of ketamine infusions may be associated with better clinical outcomes. Increased duration of relief from neuropathic pain is associated with (1) higher total infused doses of ketamine; (2) prolonged infusion durations, although the rate of infusion does not appear to be a factor; and (3) coadministration of adjunct medications such as midazolam and/or clonidine that mitigate some of the unpleasant psychomimetic side effects. However, there are few studies designed to optimize ketamine infusion protocols by defining what an effective infusion protocol entails with regard to a respective neuropathic pain condition. Therefore, despite common clinical practice, the current state of the literature leaves the use of ketamine infusions without meaningful guidance from high-quality comparative evidence. The objectives of this topical review are to (1) analyze the available clinical evidence related to ketamine infusion protocols and (2) call for clinical studies to identify optimal ketamine infusion protocols tailored for individual neuropathic pain conditions. The Oxford Center for Evidence-Based Medicine classification for levels of evidence was used to stratify the grades of clinical recommendation for each infusion variable studied.

  2. TNF α is involved in neuropathic pain induced by nucleoside reverse transcriptase inhibitor in rats

    Science.gov (United States)

    Zheng, Xuexing; Ouyang, Handong; Liu, Shue; Mata, Marina; Fink, David J.; Hao, Shuanglin

    2011-01-01

    In patients with HIV/AIDS, neuropathic pain is a common neurological complication. Infection with the HIV itself may lead to neuropathic pain, and painful symptoms are enhanced when patients are treated with nucleoside reverse transcriptase inhibitors (NRTI). The mechanisms by which NRTIs contribute to the development of neuropathic pain are not known. In the current studies, we tested the role of TNFα in antiretroviral drug-induced neuropathic pain. We administered 2′,3′-dideoxycytidine (ddC, one of the NRTIs) systemically to induce mechanical allodynia. We found that ddC induced overexpression of both mRNA and proteins of GFAP and TNFα in the spinal dorsal horn. TNFα was colocalized with GFAP in the spinal dorsal horn and with NeuN in the DRG. Knockdown of TNFα with siRNA blocked the mechanical allodynia induced by ddC. Intrathecal administration of glial inhibitor or recombinant TNF soluble receptor, reversed mechanical allodynia induced by ddC. These results suggest that TNFα is involved in NRTI-induced neuropathic pain. PMID:21741472

  3. Needs and requests--patients and physicians voices about improving the management of spinal cord injury neuropathic pain.

    Science.gov (United States)

    Norrbrink, Cecilia; Löfgren, Monika

    2016-01-01

    The present purpose was to explore patients' and involved physicians' needs and requests for improving their management of neuropathic pain following spinal cord injury (SCI). Sixteen patients with SCI and neuropathic pain, and nine physicians, were interviewed in focus-groups or individual interviews. An emergent design was used and the interviews and analyses were carried out in parallel, making it possible to use and deepen new emerging knowledge. The interviews were transcribed verbatim and processed according to content analysis. A final model with four themes described the results. Three themes covered the current situation: limitations in structure, lack of knowledge and competence, and frustrations. A fourth theme, needs and requests, described suggestions by patients and physicians for future improvements. Suggestions included increased participation, increased patient involvement in the pain rehabilitation process, support in the process of learning to live with pain, implementation of multi-modal pain rehabilitation, and the use of complementary treatments for neuropathic pain. Neuropathic pain following SCI needs to be assessed and treated using a structured, inter-disciplinary, multi-modal rehabilitation approach involving patients in planning and decision-making. For improving SCI neuropathic pain management, there is a great need for individually-tailored management, planned in a dialogue on equal terms between health care and the patient. Patients desire continuity and regularity and the possibility of receiving complementary treatments for SCI neuropathic pain. Access to structured pain rehabilitation is needed. Support and tools need to be provided in the learning-to-live with pain process.

  4. Ketamine for acute neuropathic pain in patients with spinal cord injury.

    Science.gov (United States)

    Kim, Kyongsong; Mishina, Masahiro; Kokubo, Rinko; Nakajima, Takao; Morimoto, Daijiro; Isu, Toyohiko; Kobayashi, Shiro; Teramoto, Akira

    2013-06-01

    Ketamine, an N-methyl-d-aspartic acid (NMDA) receptor antagonist, may be useful for treating neuropathic pain, which is often difficult to control. We report a prospective study of 13 patients with acute neuropathic pain due to spinal cord injury (SCI) treated with ketamine. All underwent a test challenge with 5mg ketamine. Patients with satisfactory responses were then treated intravenously and subsequently perorally with ketamine. Pre- and post-treatment pain was recorded on a visual analogue scale. All 13 patients responded positively to the ketamine test challenge and underwent continued ketamine administration. At the cessation of treatment and alter at final follow up, pain was decreased by 74.7% and 96.8%, respectively. The average administration period was 17.2 days; it was longer (59 days) in one patient treated in the subacute phase. All patients suffered allodynia-type pain and experienced 30% or less of their original pain intensity upon test challenge. Side effects were noted in five patients, although their severity did not require treatment cessation. In patients with SCI, ketamine reduced allodynia. Particularly good results were obtained in patients treated in the acute phase and these patients did not experience post-treatment symptom recurrence. Our results suggest that in patients with SCI, ketamine is useful for treating neuropathic pain in the acute phase. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Neuropathic Pain - Current Concepts | Meyer | South African Family ...

    African Journals Online (AJOL)

    Neuropathic pain (NP) represents a common and diverse group of disorders with peripheral and/or central nervous system damage or dysfunction. Many patients report intractable and severe pain that is resistant to simple analgesics. The diagnosis of NP is primarily based on clinical evaluation rather than diagnostic tests.

  6. Spinal cord stimulation and modulation of neuropathic pain

    NARCIS (Netherlands)

    de Vos, Cecilia Cecilia Clementine

    2013-01-01

    This thesis reports on the opportunities of several new applications of spinal cord stimulation (SCS) for the treatment of neuropathic pain. Our pilot study and consecutively performed international randomised controlled trial on effects of SCS in patients with painful diabetic neuropathy showed

  7. Elucidation of pathophysiology and treatment of neuropathic pain

    NARCIS (Netherlands)

    Vranken, Jan H.

    2012-01-01

    Neuropathic pain, pain arising as a direct consequence of a lesion or disease affecting the somatosensory system, is relatively common, occurring in about 1% of the population. Studies in animal models describe a number of peripheral and central pathophysiological processes after nerve injury that

  8. Multimodal therapeutic assessment of peripheral nerve stimulation in neuropathic pain: five case reports with a 20-year follow-up

    DEFF Research Database (Denmark)

    Kupers, Ron; Laere, Koen Van; Calenbergh, Frank Van

    2011-01-01

    Neuropathic pain following peripheral nerve lesion is highly resistant to conventional pain treatments but may respond well to direct electrical peripheral nerve stimulation (PNS). In the 1980s, we treated a series of 11 peripheral neuropathic pain patients with PNS. A first outcome assessment......, cool, warmth, cold pain and heat pain thresholds. Laser-evoked potentials showed an enlarged N2-P2 complex during active PNS. Positron Emission Tomography revealed that PNS decreased activation in the pain matrix at rest and during thermal stimulation. PNS led to increased blood flow not only...

  9. Mechanisms of disease: mechanism-based classification of neuropathic pain - a critical analysis

    DEFF Research Database (Denmark)

    Finnerup, Nanna Brix; Jensen, Troels Staehelin

    2006-01-01

    Classification of neuropathic pain according to etiology or localization has clear limitations. The discovery of specific molecular and cellular events following experimental nerve injury has raised the possibility of classifying neuropathic pain on the basis of the underlying neurobiological...

  10. Estrogen alleviates neuropathic pain induced after spinal cord injury by inhibiting microglia and astrocyte activation.

    Science.gov (United States)

    Lee, Jee Youn; Choi, Hae Young; Ju, Bong-Gun; Yune, Tae Young

    2018-04-16

    Neuropathic pain after spinal cord injury (SCI) is developed in about 80% of SCI patients and there is no efficient therapeutic drug to alleviate SCI-induced neuropathic pain. Here we examined the effect of estrogen on SCI-induced neuropathic pain at below-level and its effect on neuroinflammation as underlying mechanisms. Neuropathic pain is developed at late phase after SCI and a single dose of 17β-estradiol (100, 300 μg/kg) were administered to rats with neuropathic pain after SCI through intravenous injection. As results, both mechanical allodynia and thermal hyperalgesia were significantly reduced by 17β-estradiol compared to vehicle control. Both microglia and astrocyte activation in the lamina I and II of L4-5 dorsal horn was also inhibited by 17β-estradiol. In addition, the levels of p-p38MAPK and p-ERK known to be activated in microglia and p-JNK known to be activated in astrocyte were significantly decreased by 17β-estradiol. Furthermore, the mRNA expression of inflammatory mediators such as Il-1β, Il-6, iNos, and Cox-2 was more attenuated in 17β-estradiol-treated group than in vehicle-treated group. Particularly, we found that the analgesic effect by 17β-estradiol was mediated via estrogen receptors, which are expressed in dorsal horn neurons. These results suggest that 17β-estradiol may attenuate SCI-induced neuropathic pain by inhibiting microglia and astrocyte activation followed inflammation. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Duloxetine in the management of diabetic peripheral neuropathic pain

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    Boomershine CS

    2011-07-01

    Full Text Available Michelle J Ormseth, Beth A Sholz, Chad S BoomershineDivision of Rheumatology and Immunology, Vanderbilt University, Nashville, TN, USAAbstract: Diabetic neuropathy affects up to 70% of diabetics, and diabetic peripheral neuropathic pain (DPNP is the most common and debilitating of the diabetic neuropathies. DPNP significantly reduces quality of life and increases management costs in affected patients. Despite the impact of DPNP, management is poor with one-quarter of patients receiving no treatment and many treated with medications having little or no efficacy in managing DPNP. Duloxetine is one of two drugs approved by the United States Food and Drug Administration for DPNP management. Duloxetine is a serotonin and norepinephrine reuptake inhibitor (SNRI proven safe, effective, and cost-saving in reducing DPNP symptoms at a dose of 60 mg/day. Duloxetine doses greater than 60 mg/day for DPNP management are not recommended since they are no more efficacious and associated with more side effects; addition of pregabalin or gabapentin for these patients may be beneficial. Side effects of duloxetine are generally mild and typical for the SNRI class including nausea, dizziness, somnolence, fatigue, sweating, dry mouth, constipation, and diarrhea. Given its other indications, duloxetine is a particularly good choice for DPNP treatment in patients with coexisting depression, anxiety, fibromyalgia, or chronic musculoskeletal pain. Duloxetine treatment had no clinically significant effect on glycemic control and did not increase the risk of cardiovascular events in diabetes patients. However, duloxetine use should be avoided in patients with hepatic disease or severe renal impairment. Given its safety, efficacy, and tolerability, duloxetine is an excellent choice for DPNP treatment in many patients.Keywords: duloxetine, diabetic peripheral neuropathic pain, review, treatment

  12. Potential for Cell-Transplant Therapy with Human Neuronal Precursors to Treat Neuropathic Pain in Models of PNS and CNS Injury: Comparison of hNT2.17 and hNT2.19 Cell Lines

    Science.gov (United States)

    2012-01-01

    Windows. To determine differences be- tween the groups and between time points, one-way analysis of variances (ANOVAs) and paired Student ’ t-tests were...Katz, “Neuropathic pain in patients with upper-extremity nerve injury,” Physiotherapy Canada, vol. 62, no. 3, pp. 190–201, 2010. Pain Research and

  13. Antidepressants inhibit P2X4 receptor function: a possible involvement in neuropathic pain relief

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    Tozaki-Saitoh Hidetoshi

    2009-04-01

    Full Text Available Abstract Background Neuropathic pain is characterized by pain hypersensitivity to innocuous stimuli (tactile allodynia that is nearly always resistant to known treatments such as non-steroidal anti-inflammatory drugs or even opioids. It has been reported that some antidepressants are effective for treating neuropathic pain. However, the underlying molecular mechanisms are not well understood. We have recently demonstrated that blocking P2X4 receptors in the spinal cord reverses tactile allodynia after peripheral nerve injury in rats, implying that P2X4 receptors are a key molecule in neuropathic pain. We investigated a possible role of antidepressants as inhibitors of P2X4 receptors and analysed their analgesic mechanism using an animal model of neuropathic pain. Results Antidepressants strongly inhibited ATP-mediated Ca2+ responses in P2X4 receptor-expressing 1321N1 cells, which are known to have no endogenous ATP receptors. Paroxetine exhibited the most powerful inhibition of calcium influx via rat and human P2X4 receptors, with IC50 values of 2.45 μM and 1.87 μM, respectively. Intrathecal administration of paroxetine produced a striking antiallodynic effect in an animal model of neuropathic pain. Co-administration of WAY100635, ketanserin or ondansetron with paroxetine induced no significant change in the antiallodynic effect of paroxetine. Furthermore, the antiallodynic effect of paroxetine was observed even in rats that had received intrathecal pretreatment with 5,7-dihydroxytryptamine, which dramatically depletes spinal 5-hydroxytryptamine. Conclusion These results suggest that paroxetine acts as a potent analgesic in the spinal cord via a mechanism independent of its inhibitory effect on serotonin transporters. Powerful inhibition on P2X4 receptors may underlie the analgesic effect of paroxetine, and it is possible that some antidepressants clinically used in patients with neuropathic pain show antiallodynic effects, at least in part

  14. Benfotiamine relieves inflammatory and neuropathic pain in rats.

    Science.gov (United States)

    Sánchez-Ramírez, Gabriela M; Caram-Salas, Nadia L; Rocha-González, Héctor I; Vidal-Cantú, Guadalupe C; Medina-Santillán, Roberto; Reyes-García, Gerardo; Granados-Soto, Vinicio

    2006-01-13

    Benfotiamine has shown therapeutic efficacy in the treatment of painful diabetic neuropathy in human beings. However, so far there is no evidence about the efficacy of this drug in preclinical models of pain. The purpose of this study was to assess the possible antinociceptive and antiallodynic effect of benfotiamine in inflammatory and neuropathic pain models in the rat. Inflammatory pain was induced by injection of formalin in non-diabetic and diabetic (2 weeks) rats. Reduction of flinching behavior was considered as antinociception. Neuropathic pain was induced by either ligation of left L5/L6 spinal nerves or administration of streptozotocin (50 mg/kg, i.p.) in Wistar rats. Benfotiamine significantly reduced inflammatory (10-300 mg/kg) and neuropathic (75-300 mg/kg) nociception in non-diabetic and diabetic rats. Results indicate that oral administration of benfotiamine is able to reduce tactile allodynia from different origin in the rat and they suggest the use of this drug to reduce inflammatory and neuropathic pain in humans.

  15. Fear of pain in children and adolescents with neuropathic pain and complex regional pain syndrome.

    Science.gov (United States)

    Simons, Laura E

    2016-02-01

    A significant proportion of children and adolescents with chronic pain endorse elevated pain-related fear. Pain-related fear is associated with high levels of disability, depressive symptoms, and school impairment. Because of faulty nerve signaling, individuals with neuropathic pain and complex regional pain syndrome may be more prone to develop pain-related fear as they avoid use of and neglect the affected body area(s), resulting in exacerbated symptoms, muscle atrophy, maintenance of pain signaling, and ongoing pain-related disability. Not surprisingly, effective treatments for elevated pain-related fears involve exposure to previously avoided activities to downregulate incorrect pain signaling. In the context of intensive interdisciplinary pain treatment of youth with neuropathic pain, decreasing pain-related fear is associated with improved physical and psychological functioning, whereas high initial pain-related fear is a risk factor for less treatment responsiveness. An innovative approach to targeting pain-related fear and evidence of a neural response to treatment involving decoupling of the amygdala with key fear circuits in youth with complex regional pain syndrome suggest breakthroughs in our ability to ameliorate these issues.

  16. Experiences with spinal cord stimulator in patients with chronic neuropathic back pain.

    Science.gov (United States)

    Gjesdal, Kine; Furnes, Bodil; Dysvik, Elin

    2014-09-01

    Neuropathic pain is a complex, chronic, and disabling condition that has physical, functional, and psychosocial repercussions. Although the estimated prevalence of neuropathic pain in the general population ranges from 1.5% to 8%, neuropathic pain is frequently underdiagnosed and undertreated. The aims of this study were to examine the experience of patients treated with spinal cord stimulation as a pain-relieving treatment and how this may influence the patient's ability to participate in everyday life activities. A qualitative approach based on seven telephone interviews was performed. The participants were recruited from a university hospital in Norway, and all used spinal cord stimulation as a pain-relieving treatment. Qualitative content analysis was used. Two thematic findings emerged: (1) pain relief with spinal cord stimulation as a complex and individual experience and (2) challenges in adaptations in everyday life with spinal cord stimulation. Findings indicate that spinal cord stimulation can offer pain relief that can help patients achieve a meaningful life despite chronic pain. Spinal cord stimulation also may have disadvantages that should be considered before offering this treatment. It seems evident that extended information needs about working mechanism of SCS and precautions as well as follow-up are required to meet unexpected challenges in adaptation. Here the nurse has an important role when informing and following this patient group. Copyright © 2014 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  17. Examining the Time to Therapeutic Effect of Pregabalin in Spinal Cord Injury Patients With Neuropathic Pain.

    Science.gov (United States)

    Cardenas, Diana D; Emir, Birol; Parsons, Bruce

    2015-05-01

    pregabalin-treated patients than among placebo-treated patients. Finally, the timing of pregabalin's effect on pain and pain-related sleep interference was unaffected by the use of concomitant medications that were allowed for treatment of neuropathic pain in both trials. Treatment with pregabalin results in rapid time to significant improvement in both pain and pain-related sleep interference in patients with neuropathic pain due to SCI. These findings should only be used as a guide to physicians and patients as to when clinical response to pregabalin may be expected. Copyright © 2015 Elsevier HS Journals, Inc. All rights reserved.

  18. How to diagnose neuropathic pain? The contribution from clinical examination, pain questionnaires and diagnostic tests.

    Science.gov (United States)

    La Cesa, S; Tamburin, S; Tugnoli, V; Sandrini, G; Paolucci, S; Lacerenza, M; Marchettini, P; Cruccu, G; Truini, A

    2015-12-01

    Patients with peripheral and central nervous system diseases may suffer from different types of pain, namely nociceptive, neuropathic and mixed pain. Although in some cases, the distinction between these types of pain is clinically evident, yet in some patients an accurate differential diagnosis requires dedicated clinical examination, screening questionnaires and diagnostic techniques some of which are available only in specialized pain centres. This review briefly addresses the currently agreed definitions of the different types of pain and shows how clinical examination, pain questionnaires and diagnostic tests can help the clinicians in identifying neuropathic pain.

  19. Advancing Nursing Practice: Management of Neuropathic Pain With Capsaicin 8% Without Physician Supervision.

    Science.gov (United States)

    O'Brien, Joanne; Keaveny, Joseph; Pollard, Valerie; Nugent, Linda Elizabeth

    The purpose of this study was to examine the management of patient's neuropathic pain with capsaicin 8% in a nurse-led clinic when administered by 1 registered advanced nurse practitioner without physician supervision. A longitudinal, single-group, descriptive research design was used to assess pain scores and quality of life 3 times over 3 months after treatment. Patients with a diagnosis of neuropathic pain were assessed and treated with capsaicin 8% by 1 advanced nurse practitioner with prescriptive authority in a nurse-led clinic. Pain scores were collected at baseline, and self-assessed pain, activity level, and quality of life were assessed at 1 week, 4 weeks, and 3 months after treatment. Twenty-four patients were recruited, and data were analyzed using Friedman's test. In post hoc analysis, Wilcoxon signed-rank test was used with Bonferroni correction. Pain scores differed from pretreatment to posttreatment at each of the 3 time points, at rest (χ3 = 20.54, P = .001) and on movement (χ3 = 23.644, P = .001), and remained significant after Bonferroni correction. Overall, 62.5% (n = 15) of patients achieved at least a 30% reduction in self-reported pain at rest from pretreatment to 3 months, and 54% (n = 13) achieved the same reduction in pain on movement. Most improvements in patient's quality of life occurred between 1 and 4 weeks. Patient satisfaction was high, with 83% stating that they would be happy to have the treatment repeated. Single-dose capsaicin 8% decreased neuropathic pain after being administered in an outpatient setting by an experienced registered advanced nurse practitioner. Further multicenter research led by advanced nurse practitioners is needed to support high-quality, safe treatment of neuropathic pain with high-concentration capsaicin in nurse-led chronic pain clinics.

  20. Antinociception induced by rosuvastatin in murine neuropathic pain.

    Science.gov (United States)

    Miranda, Hugo F; Sierralta, Fernando; Aranda, Nicolas; Poblete, Paula; Castillo, Rodrigo L; Noriega, Viviana; Prieto, Juan Carlos

    2018-06-01

    Neuropathic pain, and subsequent hypernociception, can be induced in mice by paclitaxel (PTX) administration and partial sciatic nerve ligation (PSNL). Its pharmacotherapy has been a clinical challenge, due to a lack of effective treatment. In two models of mouse neuropathic pain (PTX and PSNL) the antinociception induced by rosuvastatin and the participation of proinflammatory biomarkers, interleukin (IL)- 1β, TBARS and glutathione were evaluated. A dose-response curve for rosuvastatin ip was obtained on cold plate, hot plate and Von Frey assays. Changes on spinal cord levels of IL-1β, glutathione and lipid peroxidation were measured at 7 and 14days in PTX and PSNL murine models. PTX or PSNL were able to induce in mice peripheral neuropathy with hypernociception, either to 7 and 14days. Rosuvastatin induced a dose dependent antinociception in hot plate, cold plate and Von Frey assays. The increased levels of IL-1β or TBARS induced by pretreatment with PTX or PSNL were reduced by rosuvastatin. The reduction of spinal cord glutathione, by PTX or PSNL, expressed as the ratio GSH/GSSG, were increased significantly in animals pretreated with rosuvastatin. The anti-inflammatory properties of statins could underlie their beneficial effects on neuropathic pain by reduction of proinflammatory biomarkers and activation of glia. The findings of this study suggest a potential usefulness of rosuvastatin in the treatment of neuropathic pain. Copyright © 2018 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  1. Neuropathic pain and spasticity: intricate consequences of spinal cord injury

    DEFF Research Database (Denmark)

    Finnerup, Nanna Brix

    2017-01-01

    of SCI, and a careful examination and characterization of the symptoms and signs, are a prerequisite for understanding the relationship between neuropathic pain and spasticity and the intricate underlying mechanisms.Spinal Cord advance online publication, 11 July 2017; doi:10.1038/sc.2017.70....

  2. Anti-allodynic Effect of Nefopam and Morphine in a Rat Model of Neuropathic Pain

    Directory of Open Access Journals (Sweden)

    Taraneh Moini Zanjani

    2013-05-01

    Full Text Available Please cite this article as: Moini Zanjani T, Saghaei E, Ameli H, Sabetkasaei M. Anti-allodynic Effect of Nefopam and Morphine in a Rat Model of Neuropathic Pain. Novel Biomed 2013;1:16-22.Background: Neuropathic pain is a chronic pain due to a disorder in the peripheral or central nervous system with different pathophysiological mechanisms. Current treatments are not effective. Here we compared the analgesic effect of nefopam, and morphine in chronic constriction injury (CCI model of neuropathic pain.Methods: Male wistar rat (150-200g, n=8 were divided into 3 different groups: 1- Saline-treated CCI group, 2- Saline-treated sham group, and 3- Drug-treated CCI groups. In CCI model of neuropathic pain, the left sciatic nerve was exposed and 4 loose chromic gut ligatures were placed around the nerve proximal to the trifurcation. Ketamine 60mg/kg and xylazine 10 mg/kg were used for anesthesia. Nefopam (10, 20, 30mg/kg, and morphine (1, 3, 5mg/kg were injected 30 minutes before surgery and continued daily to day 14 post-ligation. Von Frey filaments for mechanical allodynia and acetone test for cold allodynia were respectively used as pain behavioral tests. Experiments were performed on day 0 (before surgery and days 1, 3, 5,7,10 and 14 post injury. Behavioral studies were performed in a quiet room between 9:00 to 11:00 AM. All experiments followed the IASP guidelines on ethical standards for investigation of experimental pain in animals.Results: Nefopam (20 and 30mg/kg blocked mechanical and cold allodynia during the experimental period, but the analgesic effects of morphine (5mg/kg lasted for 7 days.Conclusions: It seems that nefopam could effectively reduce pain behavior compared to morphine with reduced adverse effects.

  3. An improved behavioural assay demonstrates that ultrasound vocalizations constitute a reliable indicator of chronic cancer pain and neuropathic pain

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    Selvaraj Deepitha

    2010-03-01

    Full Text Available Abstract Background On-going pain is one of the most debilitating symptoms associated with a variety of chronic pain disorders. An understanding of mechanisms underlying on-going pain, i.e. stimulus-independent pain has been hampered so far by a lack of behavioural parameters which enable studying it in experimental animals. Ultrasound vocalizations (USVs have been proposed to correlate with pain evoked by an acute activation of nociceptors. However, literature on the utility of USVs as an indicator of chronic pain is very controversial. A majority of these inconsistencies arise from parameters confounding behavioural experiments, which include novelty, fear and stress due to restrain, amongst others. Results We have developed an improved assay which overcomes these confounding factors and enables studying USVs in freely moving mice repetitively over several weeks. Using this improved assay, we report here that USVs increase significantly in mice with bone metastases-induced cancer pain or neuropathic pain for several weeks, in comparison to sham-treated mice. Importantly, analgesic drugs which are known to alleviate tumour pain or neuropathic pain in human patients significantly reduce USVs as well as mechanical allodynia in corresponding mouse models. Conclusions We show that studying USVs and mechanical allodynia in the same cohort of mice enables comparing the temporal progression of on-going pain (i.e. stimulus-independent pain and stimulus-evoked pain in these clinically highly-relevant forms of chronic pain.

  4. Neuropathic pain in people with cancer (part 2): pharmacological and non-pharmacological management.

    Science.gov (United States)

    Taverner, Tarnia

    2015-08-01

    The aim of this paper is to provide an overview of the management of neuropathic pain associated with cancer and to provide helpful clinical advice for nurses working with patients who may have neuropathic pain. While cancer pain is a mixed-mechanism pain, this article will focus only on neuropathic pain management. The impact of neuropathic pain on patients' quality of life is great and while many patients recover from their cancer, a significant number continue to suffer from a neuropathic pain syndrome. Management of neuropathic pain is significantly different from management of nociceptive pain with respect to pharmacological and non-pharmacological strategies. Neuropathic pain is complex, and as such requires complex management using pharmacological as well as non-pharmacological approaches. Specific drugs for neuropathic pain may be effective for some patients, but not all; therefore, ongoing and comprehensive assessment and management are required. Furthermore, these patients may require trials of several drugs before they find one that works for them. It is important for nurses to understand neuropathic pain, its manifestation, impact on quality of life and management when nursing patients with neuropathic pain associated with cancer.

  5. Koumine Attenuates Neuroglia Activation and Inflammatory Response to Neuropathic Pain

    Directory of Open Access Journals (Sweden)

    Gui-Lin Jin

    2018-01-01

    Full Text Available Despite decades of studies, the currently available drugs largely fail to control neuropathic pain. Koumine—an alkaloidal constituent derived from the medicinal plant Gelsemium elegans Benth.—has been shown to possess analgesic and anti-inflammatory properties; however, the underlying mechanisms remain unclear. In this study, we aimed to investigate the analgesic and anti-inflammatory effects and the possible underlying mechanisms of koumine. The analgesic and anti-inflammatory effects of koumine were explored by using chronic constriction injury of the sciatic nerve (CCI neuropathic pain model in vivo and LPS-induced injury in microglia BV2 cells in vitro. Immunofluorescence staining and Western blot analysis were used to assess the modulator effect of koumine on microglia and astrocyte activation after CCI surgery. Enzyme-linked immunosorbent assay (ELISA was used to evaluate the levels of proinflammatory cytokines. Western blot analysis and quantitative real-time polymerase chain reaction (qPCR were used to examine the modulator effect of koumine on microglial M1 polarization. We found that single or repeated treatment of koumine can significantly reduce neuropathic pain after nerve injury. Moreover, koumine showed inhibitory effects on CCI-evoked microglia and astrocyte activation and reduced proinflammatory cytokine production in the spinal cord in rat CCI models. In BV2 cells, koumine significantly inhibited microglia M1 polarization. Furthermore, the analgesic effect of koumine was inhibited by a TSPO antagonist PK11195. These findings suggest that the analgesic effects of koumine on CCI-induced neuropathic pain may result from the inhibition of microglia activation and M1 polarization as well as the activation of astrocytes while sparing the anti-inflammatory responses to neuropathic pain.

  6. Differential pain modulation in patients with peripheral neuropathic pain and fibromyalgia.

    Science.gov (United States)

    Gormsen, Lise; Bach, Flemming W; Rosenberg, Raben; Jensen, Troels S

    2017-12-29

    Background The definition of neuropathic pain has recently been changed by the International Association for the Study of Pain. This means that conditions such as fibromyalgia cannot, as sometimes discussed, be included in the neuropathic pain conditions. However, fibromyalgia and peripheral neuropathic pain share common clinical features such as spontaneous pain and hypersensitivity to external stimuli. Therefore, it is of interest to directly compare the conditions. Material and methods In this study we directly compared the pain modulation in neuropathic pain versus fibromyalgia by recording responses to a cold pressor test in 30 patients with peripheral neuropathic pain, 28 patients with fibromyalgia, and 26 pain-free age-and gender-matched healthy controls. Patients were asked to rate their spontaneous pain on a visual analog scale (VAS (0-100 mm) immediately before and immediately after the cold pressor test. Furthermore the duration (s) of extremity immersion in cold water was used as a measure of the pain tolerance threshold, and the perceived pain intensity at pain tolerance on the VAS was recorded on the extremity in the water after the cold pressor test. In addition, thermal (thermo tester) and mechanical stimuli (pressure algometer) were used to determine sensory detection, pain detection, and pain tolerance thresholds in different body parts. All sensory tests were done by the same examiner, in the same room, and with each subject in a supine position. The sequence of examinations was the following: (1) reaction time, (2) pressure thresholds, (3) thermal thresholds, and (4) cold pressor test. Reaction time was measured to ensure that psychomotoric inhibitions did not influence pain thresholds. Results Pain modulation induced by a cold pressor test reduced spontaneous pain by 40% on average in neuropathic pain patients, but increased spontaneous pain by 2.6% in fibromyalgia patients. This difference between fibromyalgia and neuropathic pain patients was

  7. Conditioned pain modulation: a predictor for development and treatment of neuropathic pain.

    Science.gov (United States)

    Granovsky, Yelena

    2013-09-01

    Psychophysical evaluation of endogenous pain inhibition via conditioned pain modulation (CPM) represents a new generation of laboratory tests for pain assessment. In this review we discuss recent findings on CPM in neuropathic pain and refer to psychophysical, neurophysiological, and methodological aspects of its clinical implications. Typically, chronic neuropathic pain patients express less efficient CPM, to the extent that incidence of acquiring neuropathic pain (e.g. post-surgery) and its intensity can be predicted by a pre-surgery CPM assessment. Moreover, pre-treatment CPM evaluation may assist in the correct choice of serotonin-noradrenalin reuptake inhibitor analgesic agents for individual patients. Evaluation of pain modulation capabilities can serve as a step forward in individualizing pain medicine.

  8. How diagnostic tests help to disentangle the mechanisms underlying neuropathic pain symptoms in painful neuropathies.

    Science.gov (United States)

    Truini, Andrea; Cruccu, Giorgio

    2016-02-01

    Neuropathic pain, ie, pain arising directly from a lesion or disease affecting the somatosensory afferent pathway, manifests with various symptoms, the commonest being ongoing burning pain, electrical shock-like sensations, and dynamic mechanical allodynia. Reliable insights into the mechanisms underlying neuropathic pain symptoms come from diagnostic tests documenting and quantifying somatosensory afferent pathway damage in patients with painful neuropathies. Neurophysiological investigation and skin biopsy studies suggest that ongoing burning pain primarily reflects spontaneous activity in nociceptive-fiber pathways. Electrical shock-like sensations presumably arise from high-frequency ectopic bursts generated in demyelinated, nonnociceptive, Aβ fibers. Although the mechanisms underlying dynamic mechanical allodynia remain debatable, normally innocuous stimuli might cause pain by activating spared and sensitized nociceptive afferents. Extending the mechanistic approach to neuropathic pain symptoms might advance targeted therapy for the individual patient and improve testing for new drugs.

  9. Paracetamol (acetaminophen) with or without codeine or dihydrocodeine for neuropathic pain in adults.

    Science.gov (United States)

    Wiffen, Philip J; Knaggs, Roger; Derry, Sheena; Cole, Peter; Phillips, Tudor; Moore, R Andrew

    2016-12-27

    Paracetamol, either alone or in combination with codeine or dihydrocodeine, is commonly used to treat chronic neuropathic pain. This review sought evidence for efficacy and harm from randomised double-blind studies. To assess the analgesic efficacy and adverse events of paracetamol with or without codeine or dihydrocodeine for chronic neuropathic pain in adults. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase from inception to July 2016, together with reference lists of retrieved papers and reviews, and two online study registries. We included randomised, double-blind studies of two weeks' duration or longer, comparing paracetamol, alone or in combination with codeine or dihydrocodeine, with placebo or another active treatment in chronic neuropathic pain. Two review authors independently searched for studies, extracted efficacy and adverse event data, and examined issues of study quality and potential bias. We did not carry out any pooled analyses. We assessed the quality of the evidence using GRADE. No study satisfied the inclusion criteria. Effects of interventions were not assessed as there were no included studies. We have only very low quality evidence and have no reliable indication of the likely effect. There is insufficient evidence to support or refute the suggestion that paracetamol alone, or in combination with codeine or dihydrocodeine, works in any neuropathic pain condition.

  10. Thalamic deep brain stimulation for neuropathic pain after amputation or brachial plexus avulsion.

    Science.gov (United States)

    Pereira, Erlick A C; Boccard, Sandra G; Linhares, Paulo; Chamadoira, Clara; Rosas, Maria José; Abreu, Pedro; Rebelo, Virgínia; Vaz, Rui; Aziz, Tipu Z

    2013-09-01

    Fifteen hundred patients have received deep brain stimulation (DBS) to treat neuropathic pain refractory to pharmacotherapy over the last half-century, but few during the last decade. Deep brain stimulation for neuropathic pain has shown variable outcomes and gained consensus approval in Europe but not the US. This study prospectively evaluated the efficacy at 1 year of DBS for phantom limb pain after amputation, and deafferentation pain after brachial plexus avulsion (BPA), in a single-center case series. Patient-reported outcome measures were collated before and after surgery, using a visual analog scale (VAS) score, 36-Item Short-Form Health Survey (SF-36), Brief Pain Inventory (BPI), and University of Washington Neuropathic Pain Score (UWNPS). Twelve patients were treated over 29 months, receiving contralateral, ventroposterolateral sensory thalamic DBS. Five patients were amputees and 7 had BPAs, all from traumas. A postoperative trial of externalized DBS failed in 1 patient with BPA. Eleven patients proceeded to implantation and gained improvement in pain scores at 12 months. No surgical complications or stimulation side effects were noted. In the amputation group, after 12 months the mean VAS score improved by 90.0% ± 10.0% (p = 0.001), SF-36 by 57.5% ± 97.9% (p = 0.127), UWNPS by 80.4% ± 12.7% (p stimulation demonstrated efficacy at 1 year for chronic neuropathic pain after traumatic amputation and BPA. Clinical trials that retain patients in long-term follow-up are desirable to confirm findings from prospectively assessed case series.

  11. Trigeminal nerve anatomy in neuropathic and non-neuropathic orofacial pain patients.

    Science.gov (United States)

    Wilcox, Sophie L; Gustin, Sylvia M; Eykman, Elizabeth N; Fowler, Gordon; Peck, Christopher C; Murray, Greg M; Henderson, Luke A

    2013-08-01

    Trigeminal neuralgia, painful trigeminal neuropathy, and painful temporomandibular disorders (TMDs) are chronic orofacial pain conditions that are thought to have fundamentally different etiologies. Trigeminal neuralgia and neuropathy are thought to arise from damage to or pressure on the trigeminal nerve, whereas TMD results primarily from peripheral nociceptor activation. This study sought to assess the volume and microstructure of the trigeminal nerve in these 3 conditions. In 9 neuralgia, 18 neuropathy, 20 TMD, and 26 healthy controls, the trigeminal root entry zone was selected on high-resolution T1-weighted magnetic resonance images and the volume (mm(3)) calculated. Additionally, using diffusion-tensor images (DTIs), the mean diffusivity and fractional anisotropy values of the trigeminal nerve root were calculated. Trigeminal neuralgia patients displayed a significant (47%) decrease in nerve volume but no change in DTI values. Conversely, trigeminal neuropathy subjects displayed a significant (40%) increase in nerve volume but again no change in DTI values. In contrast, TMD subjects displayed no change in volume or DTI values. The data suggest that the changes occurring within the trigeminal nerve are not uniform in all orofacial pain conditions. These structural and volume changes may have implications in diagnosis and management of different forms of chronic orofacial pain. This study reveals that neuropathic orofacial pain conditions are associated with changes in trigeminal nerve volume, whereas non-neuropathic orofacial pain is not associated with any change in nerve volume. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

  12. Dopaminergic tone does not influence pain levels during placebo interventions in patients with chronic neuropathic pain.

    Science.gov (United States)

    Skyt, Ina; Moslemi, Kurosh; Baastrup, Cathrine; Grosen, Kasper; Benedetti, Fabrizio; Petersen, Gitte L; Price, Donald D; Hall, Kathryn T; Kaptchuk, Ted J; Svensson, Peter; Jensen, Troels S; Vase, Lene

    2017-10-23

    Placebo effects have been reported in patients with chronic neuropathic pain. Expected pain levels and positive emotions are involved in the observed pain relief, but the underlying neurobiology is largely unknown. Patients with neuropathic pain are highly motivated for pain relief, and as motivational factors such as expectations of reward, as well as pain processing in itself, are related to the dopaminergic system, it can be speculated that dopamine release contributes to placebo effects in neuropathic pain. Nineteen patients with neuropathic pain after thoracic surgery were tested during a placebo intervention consisting of open and hidden applications of the pain-relieving agent lidocaine (2 mL) and no treatment. The dopamine antagonist haloperidol (2 mg) and the agonist levodopa/carbidopa (100/25 mg) were administered to test the involvement of dopamine. Expected pain levels, desire for pain relief, and ongoing and evoked pain were assessed on mechanical visual analog scales (0-10). Significant placebo effects on ongoing (P ≤ 0.003) and evoked (P ≤ 0.002) pain were observed. Expectancy and desire accounted for up to 41.2% and 71.5% of the variance in ongoing and evoked pain, respectively, after the open application of lidocaine. We found no evidence for an effect of haloperidol and levodopa/carbidopa on neuropathic pain levels (P = 0.071-0.963). Dopamine seemed to influence the levels of expectancy and desire, yet there was no evidence for indirect or interaction effects on the placebo effect. This is the first study to suggest that dopamine does not contribute to placebo effects in chronic neuropathic pain.

  13. ANALGESIC EFFECT OF INTRATHECAL BACLOFEN BOLUS ON NEUROPATHIC PAIN IN SPINAL CORD INJURY PATIENTS.

    Science.gov (United States)

    Kumru, Hatice; Benito-Penalva, Jesus; Kofler, Markus; Vidal, Joan

    2018-05-18

    GABA-ergic neurons are widely distributed throughout the central nervous system, including the spinal cord which is important for the transmission of pain impulses to the brain. Here we hypothesized that intrathecal baclofen (ITB) which is a GABA analogue might exert analgesic effects on neuropathic pain, which could be related to subtypes of pain in spinal cord injury (SCI). SCI patients with a cervical or thoracic lesion and neuropathic pain were randomized to receive either a single ITB bolus or placebo. Numerical Rating Scale (NRS), Neuropathic Pain Symptom Inventory (NPSI), and Brief Pain Inventory (BPI) were obtained for assessment of neuropathic pain. Spasticity was assessed using Modified Ashworth Scale and visual analogue scale. Evaluations were performed at baseline, and 4, 8, and 24 hours after application of ITB or placebo. Eight patients received ITB, 5 placebo. Neuropathic pain improved significantly in the ITB group based on NRS, BPI, and NPSI, which revealed an effect on all subtypes of pain. Spasticity declined significantly. In the placebo group, there was neither significant change in pain nor in spasticity. An ITB bolus exerted a significant analgesic effect on all subtypes of neuropathic pain in SCI patients. ITB has analgesic effects on all subtypes of neuropathic pain and can improve interference of neuropathic pain with activities of daily living. ITB might be a promising analgesic treatment to control neuropathic pain. Copyright © 2018. Published by Elsevier Inc.

  14. Neuropathic Pain Medication Use Does Not Alter Outcomes of Spinal Cord Stimulation for Lower Extremity Pain.

    Science.gov (United States)

    Maher, Dermot P; Martins, Yuri Chaves; Doshi, Tina; Bicket, Mark; Zhang, Kui; Hanna, George; Ahmed, Shihab

    2018-01-01

    Spinal cord stimulation (SCS) for the treatment of lower extremity pain is believed to the result of increased activity in the descending inhibitory and decreased activity in the ascending excitatory tracts. Evidence suggests that the analgesia afforded by SCS may be altered using certain neuropathic pain medications that also modulate neurotransmitters in these sensory tracts. We hypothesize that neuropathic pain medications may alter the response to SCS therapy. One hundred and fifteen subjects undergoing SCS therapy for lower extremity pain were retrospectively examined. The pharmacologic profile, including stable use of neuropathic and opioid medications, were recorded. Three separate logistic regression models examined the odds ratio of primary outcomes; a successful SCS trial, a 50% decrease in pain or a 50% reduction in opioid use one year after implant. Neither the use of opioids or neuropathic pain medications were associated with changes in the odds of a successful SCS trial or a 50% pain reduction. A higher dose of chronic opioids use prior to a trial was associated with greater odds of having a 50% reduction in opioid use following implant. OR 1.02, 95% CI 1.01-1.02, p-value neuropathic pain medications did not change the odds of either a successful SCS trial, or of experiencing a 50% reduction in pain at one year. The association between higher opioid doses and greater odds of a 50% reduction in opioid use may be the reflective of SCS's ability to reduce opioid reliance in chronic pain patients. © 2017 International Neuromodulation Society.

  15. Management of Neuropathic Chronic Pain with Methadone Combined with Ketamine: A Randomized, Double Blind, Active-Controlled Clinical Trial.

    Science.gov (United States)

    Rigo, Flavia Karine; Trevisan, Gabriela; Godoy, Maria C; Rossato, Mateus Fortes; Dalmolin, Gerusa D; Silva, Mariane A; Menezes, Mirian S; Caumo, Wolnei; Ferreira, Juliano

    2017-03-01

    Methadone and ketamine are used in neuropathic pain management. However, the benefits of both drugs association are uncertain in the treatment of neuropathic pain. Our primary objective was test the hypothesis that oral methadone combined with oral ketamine is more effective than oral methadone or ketamine alone in reducing neuropathic pain. We conducted a randomized, double blind, active-controlled parallel-group clinical trial. Forty-two patients with neuropathic pain refractory to conventional therapy were randomly assigned to receive oral methadone (n = 14), ketamine (n = 14), or methadone plus ketamine (n = 14) over a 3-month period. During these 90 days, we observed pain scores using a visual analogical scale (VAS), allodynia, burning/shooting pain, and some side effects. All treatments were effective in reducing pain scores by at least 40%. However, a significant improvement in pain was observed only in the ketamine alone group compared with both the methadone or methadone/ketamine groups. No significant differences were observed among the treatment groups for the reduction of burning or shooting pain, while ketamine alone was more effective than methadone or methadone/ketamine for the reduction of allodynia. Formal assessment for awareness of the allocation was not performed, some co-intervention bias may have occurred, our results could be only relevant to the patient population investigated and the use of VAS as the primary outcome detect changes in pain intensity but not to assess neuropathic pain symptoms. This study indicates that ketamine was better than methadone or methadone/ketamine for treating neuropathic pain.Key words: Multimodal analgesia, refractory pain, NMDA receptor, opioid.

  16. Activated microglia in the spinal cord underlies diabetic neuropathic pain.

    Science.gov (United States)

    Wang, Dongmei; Couture, Réjean; Hong, Yanguo

    2014-04-05

    Diabetes mellitus is an increasingly common chronic medical condition. Approximately 30% of diabetic patients develop neuropathic pain, manifested as spontaneous pain, hyperalgesia and allodynia. Hyperglycemia induces metabolic changes in peripheral tissues and enhances oxidative stress in nerve fibers. The damages and subsequent reactive inflammation affect structural properties of Schwann cells and axons leading to the release of neuropoietic mediators, such as pro-inflammatory cytokines and pro-nociceptive mediators. Therefore, diabetic neuropathic pain (DNP) shares some histological features and underlying mechanisms with traumatic neuropathy. DNP displays, however, other distinct features; for instance, sensory input to the spinal cord decreases rather than increasing in diabetic patients. Consequently, development of central sensitization in DNP involves mechanisms that are distinct from traumatic neuropathic pain. In DNP, the contribution of spinal cord microglia activation to central sensitization and pain processes is emerging as a new concept. Besides inflammation in the periphery, hyperglycemia and the resulting production of reactive oxygen species affect the local microenvironment in the spinal cord. All these alterations could trigger resting and sessile microglia to the activated phenotype. In turn, microglia synthesize and release pro-inflammatory cytokines and neuroactive molecules capable of inducing hyperactivity of spinal nociceptive neurons. Hence, it is imperative to elucidate glial mechanisms underlying DNP for the development of effective therapeutic agents. The present review highlights the recent developments regarding the contribution of spinal microglia as compelling target for the treatment of DNP. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Pain relief with lidocaine 5% patch in localized peripheral neuropathic pain in relation to pain phenotype

    DEFF Research Database (Denmark)

    Torgaard Demant, Dyveke; Lund, Karen; Finnerup, Nanna B

    2015-01-01

    In neuropathic pain with irritable nociceptor phenotype, up-regulation of sodium channels on nociceptors is supposed to be an important pain mechanism that may be targeted by topical sodium channel blockade. This randomised, double-blind, phenotype-panel, cross-over study with 4-week treatment pe...... had an effect on peripheral neuropathic pain, and it may be most efficacious in patients with irritable nociceptor phenotype. The lack of significant phenotype differences may be caused by too low statistical power.......In neuropathic pain with irritable nociceptor phenotype, up-regulation of sodium channels on nociceptors is supposed to be an important pain mechanism that may be targeted by topical sodium channel blockade. This randomised, double-blind, phenotype-panel, cross-over study with 4-week treatment...... periods of lidocaine 5% patch and placebo was performed to search for phenotype differences in effect. The primary efficacy measure was the total pain intensity on an 11-point numeric rating scale (NRS), and the primary objective was to compare the effect of lidocaine in patients with and without...

  18. Blocking spinal CCR2 with AZ889 reversed hyperalgesia in a model of neuropathic pain

    Directory of Open Access Journals (Sweden)

    Vaillancourt François

    2010-12-01

    Full Text Available Abstract Background The CCR2/CCL2 system has been identified as a regulator in the pathogenesis of neuropathy-induced pain. However, CCR2 target validation in analgesia and the mechanism underlying antinociception produced by CCR2 antagonists remains poorly understood. In this study, in vitro and in vivo pharmacological approaches using a novel CCR2 antagonist, AZ889, strengthened the hypothesis of a CCR2 contribution to neuropathic pain and provided confidence over the possibilities to treat neuropathic pain with CCR2 antagonists. Results We provided evidence that dorsal root ganglia (DRG cells harvested from CCI animals responded to stimulation by CCL2 with a concentration-dependent calcium rise involving PLC-dependent internal stores. This response was associated with an increase in evoked neuronal action potentials suggesting these cells were sensitive to CCR2 signalling. Importantly, treatment with AZ889 abolished CCL2-evoked excitation confirming that this activity is CCR2-mediated. Neuronal and non-neuronal cells in the spinal cord were also excited by CCL2 applications indicating an important role of spinal CCR2 in neuropathic pain. We next showed that in vivo spinal intrathecal injection of AZ889 produced dose-dependent analgesia in CCI rats. Additionally, application of AZ889 to the exposed spinal cord inhibited evoked neuronal activity and confirmed that CCR2-mediated analgesia involved predominantly the spinal cord. Furthermore, AZ889 abolished NMDA-dependent wind-up of spinal withdrawal reflex pathway in neuropathic animals giving insight into the spinal mechanism underlying the analgesic properties of AZ889. Conclusions Overall, this study strengthens the important role of CCR2 in neuropathic pain and highlights feasibility that interfering on this mechanism at the spinal level with a selective antagonist can provide new analgesia opportunities.

  19. Peripheral nerve field stimulation for chronic neuropathic pain: a single institution experience.

    Science.gov (United States)

    D'Ammando, A; Messina, G; Franzini, A; Dones, I

    2016-04-01

    Peripheral nerve field stimulation (PNFS) is a novel neurosurgical procedure consisting of implantation of subcutaneous leads in specific painful areas in different types of painful, drug-resistant syndromes. The objective of this study was to evaluate the efficacy of PNFS in several patients affected by different chronic neuropathic pain syndromes, along with its risks, limits and possible correlation between the results achieved and the patients' main symptoms. Twenty-two patients affected by different types of chronic neuropathic pain were submitted to PNFS at the Department of Neurosurgery of the Istituto Neurologico "C. Besta" in Milan between July 2009 and July 2013. The visual analog scale (VAS) and variations in the use of analgesic drugs, along with complications, were considered to assess results. In 59 % of our patients, an average pain reduction of 5.50 points on the visual analog scale was observed (average pre-implant score 8.86 and average post-implant score 3.36). These patients reduced their analgesic drug use after PNFS. We observed no early or long-term complications after our last follow-up evaluation. PNFS can be considered an effective and safe option to treat carefully selected, drug-resistant and chronic neuropathic pain patients; the reversibility of the procedure and its lack, at least in our hands, of long-term complications may contribute to wider use of this procedure.

  20. Orofacial Neuropathic Pain Leads to a Hyporesponsive Barrel Cortex with Enhanced Structural Synaptic Plasticity.

    Science.gov (United States)

    Thibault, Karine; Rivière, Sébastien; Lenkei, Zsolt; Férézou, Isabelle; Pezet, Sophie

    2016-01-01

    Chronic pain is a long-lasting debilitating condition that is particularly difficult to treat due to the lack of identified underlying mechanisms. Although several key contributing processes have been described at the level of the spinal cord, very few studies have investigated the supraspinal mechanisms underlying chronic pain. Using a combination of approaches (cortical intrinsic imaging, immunohistochemical and behavioural analysis), our study aimed to decipher the nature of functional and structural changes in a mouse model of orofacial neuropathic pain, focusing on cortical areas involved in various pain components. Our results show that chronic neuropathic orofacial pain is associated with decreased haemodynamic responsiveness to whisker stimulation in the barrel field cortex. This reduced functional activation is likely due to the increased basal neuronal activity (measured indirectly using cFos and phospho-ERK immunoreactivity) observed in several cortical areas, including the contralateral barrel field, motor and cingulate cortices. In the same animals, immunohistochemical analysis of markers for active pre- or postsynaptic elements (Piccolo and phospho-Cofilin, respectively) revealed an increased immunofluorescence in deep cortical layers of the contralateral barrel field, motor and cingulate cortices. These results suggest that long-lasting orofacial neuropathic pain is associated with exacerbated neuronal activity and synaptic plasticity at the cortical level.

  1. Prevalence of acute neuropathic pain after cancer surgery: A prospective study

    Directory of Open Access Journals (Sweden)

    P N Jain

    2014-01-01

    Full Text Available Background and Aims: Acute neuropathic pain (ANP is an under-recognised and under-diagnosed condition and often difficult to treat. If left untreated, it may further transform into persistent post-operative chronic pain leading to a disability. Aims: This prospective study was undertaken on 300 patients to identify the prevalence of ANP in the post-operative period by using a neuropathic pain detection questionnaire tool. Methods: This is an open-label study in which patients with six different types of cancer surgeries (Thoracic, gastro-intestinal, gynae/urology, bone/soft-tissue, head and neck and breast subgroups-50 each were included for painDETECT questionnaire tool on the 2 nd and 7 th day surgery. Results: This study found a 10% point prevalence of ANP. Analysis showed that 25 patients had ′possible′ ANP, the maximum from urological cancer surgery (6 followed by thoracic surgery (5. Five patients were found to have ′positive′ ANP including 2 groin node dissection, 2 hemipelvectomy and 1 oesophagectomy. Conclusion: Significant relationship between severity of post-operative pain was found with the occurrence of ANP in the post-operative period requiring a special attention to neuropathic pain assessment. Larger studies are required with longer follow-up to identify accurately the true prevalence and causative factors of ANP after surgery.

  2. Treatment of Chronic Refractory Neuropathic Pelvic Pain with High-Frequency 10-kilohertz Spinal Cord Stimulation.

    Science.gov (United States)

    Simopoulos, Thomas; Yong, Robert J; Gill, Jatinder S

    2017-11-06

    Chronic neuropathic pelvic pain remains a recalcitrant problem in the field of pain management. Case series on application of 10 kHz spinal cord stimulation is presented. High frequency stimulation can improve chronic neuropathic pain states that are known to be mediated at the conus medullaris and offers another avenue for the treatment of these patients. © 2017 World Institute of Pain.

  3. Synaptic Homeostasis and Allostasis in the Dentate Gyrus Caused by Inflammatory and Neuropathic Pain Conditions

    Directory of Open Access Journals (Sweden)

    Rui-Rui Wang

    2018-01-01

    Full Text Available It has been generally accepted that pain can cause imbalance between excitation and inhibition (homeostasis at the synaptic level. However, it remains poorly understood how this imbalance (allostasis develops in the CNS under different pain conditions. Here, we analyzed the changes in both excitatory and inhibitory synaptic transmission and modulation of the dentate gyrus (DG under two pain conditions with different etiology and duration. First, it was revealed that the functions of the input-output (I/O curves for evoked excitatory postsynaptic currents (eEPSCs following the perforant path (PP stimulation were gained under both acute inflammatory and chronic neuropathic pain conditions relative to the controls. However, the functions of I/O curves for the PP-evoked inhibitory postsynaptic currents (eIPSCs differed between the two conditions, namely it was greatly gained under inflammatory condition, but was reduced under neuropathic condition in reverse. Second, both the frequency and amplitude of miniature IPSCs (mIPSCs were increased under inflammatory condition, however a decrease in frequency of mIPSCs was observed under neuropathic condition. Finally, the spike discharge of the DG granule cells in response to current injection was significantly increased by neuropathic pain condition, however, no different change was found between inflammatory pain condition and the control. These results provide another line of evidence showing homeostatic and allostatic modulation of excitatory synaptic transmission by inhibitory controls under different pathological pain conditions, hence implicating use of different therapeutic approaches to maintain the homeostasis between excitation and inhibition while treating different conditions of pathological pain.

  4. Motor cortex stimulation in the treatment of central and neuropathic pain.

    Science.gov (United States)

    Nguyen, J P; Lefaucher, J P; Le Guerinel, C; Eizenbaum, J F; Nakano, N; Carpentier, A; Brugières, P; Pollin, B; Rostaing, S; Keravel, Y

    2000-01-01

    Motor cortex stimulation has been proposed for the treatment of central pain. Thirty-two patients with refractory central and neuropathic pain of peripheral origin were treated by chronic stimulation of the motor cortex between May 1993 and January 1997. The mean follow-up was 27.3 months. The first 24 patients were operated on according to the technique described by Tsubokawa. The last 13 cases (8 new patients and 5 reinterventions) were operated on by a technique including localization by superficial CT reconstruction of the central region and neuronavigator guidance. The position of the central sulcus was confirmed by the use of intraoperative somatosensory evoked potentials. The somatotopic organization of the motor cortex was established preoperatively by studying the motor responses at stimulation of the motor cortex through the dura. Ten of the 13 patients with central pain (77%) and 10 of the 12 patients with neuropathic facial pain experienced substantial pain relief (83.3%). One of the three patients with post-paraplegia pain was clearly improved. A satisfactory result was obtained in one patient with pain related to plexus avulsion and in one patient with pain related to intercostal herpes zoster. None of the patients developed epileptic seizures. Our results confirm that chronic stimulation of the motor cortex is an effective method in treating certain forms of refractory pain.

  5. Fisetin exerts antihyperalgesic effect in a mouse model of neuropathic pain: engagement of spinal serotonergic system

    Science.gov (United States)

    Zhao, Xin; Wang, Chuang; Cui, Wu-Geng; Ma, Qing; Zhou, Wen-Hua

    2015-01-01

    Fisetin, a natural flavonoid, has been shown in our previous studies to exert antidepressant-like effect. As antidepressant drugs are clinically used to treat chronic neuropathic pain, this work aimed to investigate the potential antinociceptive efficacies of fisetin against neuropathic pain and explore mechanism(s). We subjected mice to chronic constriction injury (CCI) by loosely ligating the sciatic nerves, and Hargreaves test or von Frey test was used to assess thermal hyperalgesia or mechanical allodynia, respectively. Chronic fisetin treatment (5, 15 or 45 mg/kg, p.o.) ameliorated thermal hyperalgesia (but not mechanical allodynia) in CCI mice, concomitant with escalated levels of spinal monoamines and suppressed monoamine oxidase (MAO)-A activity. The antihyperalgesic action of fisetin was abolished by chemical depletion of spinal serotonin (5-HT) but potentiated by co-treatment with 5-HTP, a precursor of 5-HT. Moreover, intraperitoneal (i.p.) or intrathecal (i.t.) co-treatment with 5-HT7 receptor antagonist SB-258719 completely abrogated fisetin's antihyperalgesia. These findings confirm that chronic fisetin treatment exerts antinociceptive effect on thermal hyperalgesia in neuropathic mice, with spinal serotonergic system (coupled with 5-HT7) being critically involved. Of special benefit, fisetin attenuated co-morbidly behavioral symptoms of depression and anxiety (evaluated in forced swim test, novelty suppressed feeding test and light-dark test) evoked by neuropathic pain. PMID:25761874

  6. Transient urinary retention and chronic neuropathic pain associated with genital herpes simplex virus infection.

    Science.gov (United States)

    Haanpää, Maija; Paavonen, Jorma

    2004-10-01

    Genital herpes (GH) causes genital ulcer disease, severe transient pain, and often paresthesias. Whether or not GH can cause urinary retention or chronic neuropathic pain is not well known. We present two immunocompetent patients with GH associated with neuropathic symptoms. We also review the literature on GH and associated neurologic problems. Patient 1 had primary herpes simplex virus (HSV)-2 infection with transient urinary retention and chronic bilateral neuropathic pain in the sacral area. Patient 2 had recurrent HSV-1 associated with unitaleral chronic neuropathic pain in the sacral area. Although transient urinary retention associated with GH is not uncommon, chronic neuropathic pain has not been reported previously. Our cases show that chronic neuropathic pain, that is "pain initiated or caused by a primary lesion or dysfunction in the nervous system," can follow genital HSV infection.

  7. Pain management strategies for neuropathic pain in Fabry disease--a systematic review

    NARCIS (Netherlands)

    Schuller, Y.; Linthorst, G. E.; Hollak, C. E. M.; van Schaik, I. N.; Biegstraaten, M.

    2016-01-01

    Neuropathic pain is one of the key features of (classical) Fabry disease (FD). No randomized clinical trials comparing effectiveness of different pain management strategies have been performed. This review aims to give an overview of existing pain management strategies. PubMed and Embase were

  8. Parameter Optimization Analysis of Prolonged Analgesia Effect of tDCS on Neuropathic Pain Rats

    Science.gov (United States)

    Wen, Hui-Zhong; Gao, Shi-Hao; Zhao, Yan-Dong; He, Wen-Juan; Tian, Xue-Long; Ruan, Huai-Zhen

    2017-01-01

    Background: Transcranial direct current stimulation (tDCS) is widely used to treat human nerve disorders and neuropathic pain by modulating the excitability of cortex. The effectiveness of tDCS is influenced by its stimulation parameters, but there have been no systematic studies to help guide the selection of different parameters. Objective: This study aims to assess the effects of tDCS of primary motor cortex (M1) on chronic neuropathic pain in rats and to test for the optimal parameter combinations for analgesia. Methods: Using the chronic neuropathic pain models of chronic constriction injury (CCI), we measured pain thresholds before and after anodal-tDCS (A-tDCS) using different parameter conditions, including stimulation intensity, stimulation time, intervention time and electrode located (ipsilateral or contralateral M1 of the ligated paw on male/female CCI models). Results: Following the application of A-tDCS over M1, we observed that the antinociceptive effects were depended on different parameters. First, we found that repetitive A-tDCS had a longer analgesic effect than single stimulus, and both ipsilateral-tDCS (ip-tDCS) and contralateral-tDCS (con-tDCS) produce a long-lasting analgesic effect on neuropathic pain. Second, the antinociceptive effects were intensity-dependent and time-dependent, high intensities worked better than low intensities and long stimulus durations worked better than short stimulus durations. Third, timing of the intervention after injury affected the stimulation outcome, early use of tDCS was an effective method to prevent the development of pain, and more frequent intervention induced more analgesia in CCI rats, finally, similar antinociceptive effects of con- and ip-tDCS were observed in both sexes of CCI rats. Conclusion: Optimized protocols of tDCS for treating antinociceptive effects were developed. These findings should be taken into consideration when using tDCS to produce analgesic effects in clinical applications. PMID

  9. Pain severity and the economic burden of neuropathic pain in the United States: BEAT Neuropathic Pain Observational Study

    Directory of Open Access Journals (Sweden)

    Schaefer C

    2014-10-01

    Full Text Available Caroline Schaefer,1 Alesia Sadosky,2 Rachael Mann,3 Shoshana Daniel,4 Bruce Parsons,2 Michael Tuchman,5 Alan Anschel,6 Brett R Stacey,7 Srinivas Nalamachu,8 Edward Nieshoff9 1Covance Market Access Services Inc., Gaithersburg, MD, 2Pfizer, Inc., New York, NY, 3Covance Market Access Services Inc., San Diego, CA, 4Covance Market Access Services Inc., Conshohocken, PA, 5Palm Beach Neurological Center, Palm Beach Gardens, FL, 6Rehabilitation Institute of Chicago, Chicago, IL, 7Oregon Health and Science University, Portland, OR, 8International Clinical Research Institute, Overland Park, KS, 9Rehabilitation Institute of Michigan/Wayne State University, Detroit, MI, USABackground: As with many chronic conditions, patients with neuropathic pain (NeP are high consumers of health care resources. However, limited literature exists on the economic burden of NeP, including its impact on productivity. The aim of this study was to characterize health care resource utilization, productivity, and costs associated with NeP by pain severity level in US adults.Methods: Subjects (n=624 with painful diabetic peripheral neuropathy, human immunodeficiency virus-related peripheral NeP, post-trauma/post-surgical NeP, spinal cord injury with NeP, chronic low back pain with NeP, and small fiber neuropathy were recruited during routine office visits to US community-based general practitioners and specialists. Clinicians captured clinical characteristics, NeP-related medications, and health care resource utilization based on 6-month retrospective medical chart review. Subjects completed questionnaires on demographics, pain/symptoms, costs, and productivity. Brief Pain Inventory pain severity scores were used to classify subjects by mild, moderate, or severe pain. Annualized NeP-related costs (adjusted for covariates were estimated, and differences across pain severity groups were evaluated.Results: In total, 624 subjects were recruited (mean age 55.5±13.7 years; 55.4% male

  10. Neuropathic Pain Experiences of Spinal Cord Injury Patients.

    Science.gov (United States)

    Li, Chin-Ching; Lin, Hung-Ru; Tsai, Ming-Dar; Tsay, Shiow-Luan

    2017-11-09

    Neuropathic pain (NP) is a common, severe problem that affects spinal cord injury (SCI) patients. Only SCI patients truly understand the impact and extent of this type of pain. The aim of this study was to understand the NP experienced by SCI patients and the influence of this type of pain on their daily life. A qualitative design was used. An interview guide including a semistructured questionnaire and in-depth interviews was conducted with SCI patients with NP in a neurorehabilitation department at a medical center in northern Taiwan. The data were collected using a purposive sampling method. Content analysis was performed on the interview data, which were obtained from 13 SCI patients with NP. Three themes and eight subthemes were identified that described the NP experience of the participants and the influence of NP on their daily life. The three themes included elusive pain (changing and individual pain sensations, erratically haunting threat, and phantom limb sensations), complicated feelings about pain (converting depression into an active attitude toward life, having feelings of anticipation and anxiety about future pain relief, and facing and experiencing pain), and renewed hope (bravely fighting pain and seeking pain relief methods). This study revealed three important themes of NP experienced by SCI patients, including elusive pain, complicated feelings about pain, and renewed hope. Nurses should understand the nature of NP, provide a thorough pain assessment, and design a proper pain management plan to care effectively for patients with NP.

  11. The characteristics of chronic pain after non-traumatic, non-compressive myelopathy: Focus on neuropathic pain.

    Science.gov (United States)

    Eom, Young In; Kim, Min; Joo, In Soo

    2017-05-01

    The aim of this study was to assess the characteristics of neuropathic pain after non-traumatic, non-compressive (NTNC) myelopathy and find potential predictors for neuropathic pain. We analyzed 54 patients with NTNC myelopathy. The Short Form McGill Pain Questionnaire (SF-MPQ) and the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) were used to assess pain. Health-related QOL was evaluated by the Short Form 36-item (SF-36) health survey. Out of 48 patients with pain, 16 (33.3%) patients experienced neuropathic pain. Mean age was significantly lower in patients with neuropathic pain than in patients with non-neuropathic pain (39.1 ± 12.5 vs. 49.8 ± 9.3, P = 0.002). There were no statistically significant differences in the other variables including sex, etiology of myelopathy, pain and QOL scores between the two groups. A binary logistic regression revealed that onset age under 40, and non-idiopathic etiology were independent predictors of the occurrence of neuropathic pain. Both SF-MPQ and LANSS scores were significantly correlated with SF-36 scores, adjusted by age, sex, presence of diabetes mellitus, and current EDSS scores (r = -0.624, P Neuropathic pain must be one of serious complications in patients with NTNC myelopathy and also affects their quality of life. Onset age and etiology of myelopathy are important factors in the development of neuropathic pain in NTNC myelopathy.

  12. Antidepressants Are Effective in Decreasing Neuropathic Pain After SCI: A Meta-Analysis.

    Science.gov (United States)

    Mehta, Swati; Guy, Stacey; Lam, Tracey; Teasell, Robert; Loh, Eldon

    2015-01-01

    To systematically review and assess the effectiveness and safety of antidepressants for neuropathic pain among individuals with spinal cord injury (SCI). A systematic search was conducted using multiple databases for relevant articles published from 1980 to April 2014. Randomized controlled trials (RCTs) involving antidepressant treatment of neuropathic pain with ≥ 3 individuals and ≥ 50% of study population with SCI were included. Two independent reviewers selected studies based on inclusion criteria and then extracted data. Pooled analysis using Cohen's d to calculate standardized mean difference, standard error, and 95% confidence interval for primary (pain) and other secondary outcomes was conducted. Four RCTs met inclusion criteria. Of these, 2 studies assessed amitriptyline, 1 trazadone, and 1 duloxetine among individuals with neuropathic SCI pain. A small effect was seen in the effectiveness of antidepressants in decreasing pain among individuals with SCI (standardized mean difference = 0.34 ± 0.15; 95% CI, 0.05-0.62; P = .02). A number needed to treat of 3.4 for 30% or more pain relief was found by pooling 2 studies. Of these, significantly higher risk of experiencing constipation (risk ratio [RR] = 1.74; 95% CI, 1.09-2.78; P = .02) and dry mouth (RR = 1.39; 95% CI, 1.04-1.85; P = .02) was found amongst individuals receiving antidepressant treatment compared to those in the control group. The current meta-analysis demonstrates that antidepressants are effective in reducing neuropathic SCI pain. However, this should be interpreted with caution due to the limited number of studies. Further evaluation of long-term therapeutic options may be required.

  13. Interventional management of neuropathic pain: NeuPSIG recommendations

    Science.gov (United States)

    Dworkin, Robert H.; O’Connor, Alec B.; Kent, Joel; Mackey, Sean C.; Raja, Srinivasa N.; Stacey, Brett R.; Levy, Robert M.; Backonja, Miroslav; Baron, Ralf; Harke, Henning; Loeser, John D.; Treede, Rolf-Detlef; Turk, Dennis C.; Wells, Christopher D.

    2015-01-01

    Neuropathic pain (NP) is often refractory to pharmacologic and non-interventional treatment. On behalf of the International Association for the Study of Pain Neuropathic Pain Special Interest Group (NeuPSIG), the authors evaluated systematic reviews, clinical trials, and existing guidelines for the interventional management of NP. Evidence is summarized and presented for neural blockade, spinal cord stimulation (SCS), intrathecal medication, and neurosurgical interventions in patients with the following peripheral and central NP conditions: herpes zoster and postherpetic neuralgia (PHN); painful diabetic and other peripheral neuropathies; spinal cord injury NP; central post-stroke pain; radiculopathy and failed back surgery syndrome (FBSS); complex regional pain syndrome (CRPS); and trigeminal neuralgia and neuropathy. Due to the paucity of high-quality clinical trials, no strong recommendations can be made. Four weak recommendations based on the amount and consistency of evidence, including degree of efficacy and safety, are: (1) epidural injections for herpes zoster; (2) steroid injections for radiculopathy; (3) SCS for FBSS; and (4) SCS for CRPS type 1. Based on the available data, we recommend not to use sympathetic blocks for PHN nor RF lesions for radiculopathy. No other conclusive recommendations can be made due to the poor quality of available of data. Whenever possible, these interventions should either be part of randomized clinical trials or documented in pain registries. Priorities for future research include randomized clinical trials; long-term studies; and head-to-head comparisons among different interventional and non-interventional treatments. PMID:23748119

  14. Orofacial neuropathic pain reduces spontaneous burrowing behavior in rats.

    Science.gov (United States)

    Deseure, K; Hans, G

    2018-07-01

    It was recently reported that spontaneous burrowing behavior is decreased after tibial nerve transection, spinal nerve transection and partial sciatic nerve ligation. It was proposed that spontaneous burrowing could be used as a measure of the impact of neuropathic pain after peripheral nerve injury. It has remained unclear whether the reduction in burrowing behavior is caused directly by pain or hypersensitivity in the affected limbs, making it more difficult to perform burrowing, or by a pain induced decrease in the general wellbeing, thus reducing the motivation to burrow. We studied burrowing behavior after infraorbital nerve injury, a model of orofacial neuropathic pain that does not affect the limbs. Burrowing behavior was significantly reduced after infraorbital nerve injury. Isolated face grooming and responsiveness to mechanical von Frey stimulation of the infraorbital nerve territory were significantly increased after infraorbital nerve injury, indicative, respectively, of spontaneous pain and mechanical allodynia. It is concluded that spontaneous burrowing may provide a measure of the global impact of pain on the animal's wellbeing after peripheral nerve injury and incorporation of this behavioral assay in preclinical drug testing may improve the predictive validity of currently used pain models. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Irrational drug use in neuropathic pain treatment: a twoyear data ...

    African Journals Online (AJOL)

    Irrational drug use in neuropathic pain treatment: a twoyear data analysis. E Tan, A Akıncı, G Ayvaz, T Erbaş, M Ertaş, O Güç, S Hepgüler, S Kiraz, SZ Oşar, S Öztürk, NS Özyalçın, S Palaoğlu, M Uyar, S Ünal, S Yalçın ...

  16. Spinal SIRT1 activation attenuates neuropathic pain in mice.

    Directory of Open Access Journals (Sweden)

    Haijun Shao

    Full Text Available Abnormal histone acetylation occurs during neuropathic pain through an epigenetic mechanism. Silent information regulator 1 (sir2 or SIRT1, a NAD-dependent deacetylase, plays complex systemic roles in a variety of processes through deacetylating acetylated histone and other specific substrates. But the role of SIRT1 in neuropathic pain is not well established yet. The present study was intended to detect SIRT1 content and activity, nicotinamide (NAM and nicotinamide adenine dinucleotide (NAD in the spinal cord using immunoblotting or mass spectroscopy over time in mice following chronic constriction injury (CCI or sham surgery. In addition, the effect of intrathecal injection of NAD or resveratrol on thermal hyperalgesia and mechanical allodynia was evaluated in CCI mice. Finally, we investigated whether SIRT1 inhibitor EX-527 could reverse the anti-nociceptive effect of NAD or resveratrol. It was found that spinal SIRT1 expression, deacetylase activity and NAD/NAM decreased significantly 1, 3, 7, 14 and 21 days after CCI surgery as compared with sham group. In addition, daily intrathecal injection of 5 µl 800 mM NAD 1 h before and 1 day after CCI surgery or single intrathecal injection of 5 µl 90 mM resveratrol 1 h before CCI surgery produced a transient inhibitory effect on thermal hyperalgesia and mechanical allodynia in CCI mice. Finally, an intrathecal injection of 5 µl 1.2 mM EX-527 1 h before NAD or resveratrol administration reversed the anti-nociceptive effect of NAD or resveratrol. These data indicate that the reduction in SIRT1 deacetylase activity may be a factor contributing to the development of neuropathic pain in CCI mice. Our findings suggest that the enhancement of spinal NAD/NAM and/or SIRT1 activity may be a potentially promising strategy for the prevention or treatment of neuropathic pain.

  17. Motor cortex stimulation and neuropathic pain: how does motor cortex stimulation affect pain-signaling pathways?

    Science.gov (United States)

    Kim, Jinhyung; Ryu, Sang Baek; Lee, Sung Eun; Shin, Jaewoo; Jung, Hyun Ho; Kim, Sung June; Kim, Kyung Hwan; Chang, Jin Woo

    2016-03-01

    Neuropathic pain is often severe. Motor cortex stimulation (MCS) is used for alleviating neuropathic pain, but the mechanism of action is still unclear. This study aimed to understand the mechanism of action of MCS by investigating pain-signaling pathways, with the expectation that MCS would regulate both descending and ascending pathways. Neuropathic pain was induced in Sprague-Dawley rats. Surface electrodes for MCS were implanted in the rats. Tactile allodynia was measured by behavioral testing to determine the effect of MCS. For the pathway study, immunohistochemistry was performed to investigate changes in c-fos and serotonin expression; micro-positron emission tomography (mPET) scanning was performed to investigate changes of glucose uptake; and extracellular electrophysiological recordings were performed to demonstrate brain activity. MCS was found to modulate c-fos and serotonin expression. In the mPET study, altered brain activity was observed in the striatum, thalamic area, and cerebellum. In the electrophysiological study, neuronal activity was increased by mechanical stimulation and suppressed by MCS. After elimination of artifacts, neuronal activity was demonstrated in the ventral posterolateral nucleus (VPL) during electrical stimulation. This neuronal activity was effectively suppressed by MCS. This study demonstrated that MCS effectively attenuated neuropathic pain. MCS modulated ascending and descending pain pathways. It regulated neuropathic pain by affecting the striatum, periaqueductal gray, cerebellum, and thalamic area, which are thought to regulate the descending pathway. MCS also appeared to suppress activation of the VPL, which is part of the ascending pathway.

  18. Fibromyalgia as a neuropathic pain syndrome

    Directory of Open Access Journals (Sweden)

    Manuel Martinez-Lavin

    2003-06-01

    Full Text Available This article discusses scientific evidence supporting the notion that all fibromyalgia (FM features can be explained on the basis of autonomic (sympathetic nervous system dysfunction. Also suggests that FM main features (widespread pain and tenderness at palpation on specific anatomic points are manifestations of painful neuropathy. On these bases, a holistic approach for FM treatment is proposed.

  19. Macrophage-to-sensory neuron crosstalk mediated by Angiotensin II type-2 receptor elicits neuropathic pain

    OpenAIRE

    Krause, Eric; Shepherd, Andrew; Mickle, Aaron; Copits, Bryan; Karlsson, Pall; Kadunganattil, Suraj; Golden, Judith; Tadinada, Satya; Mack, Madison; Haroutounian, Simon; De Kloet, Annette; Samineni, Vijay; Valtcheva, Manouela; Mcilvried, Lisa; Sheahan, Tayler

    2017-01-01

    Peripheral nerve damage initiates a complex series of cellular and structural processes that culminate in chronic neuropathic pain. Our study defines local angiotensin signaling via activation of the Angiotensin II (Ang II) type-2 receptor (AT2R) on macrophages as the critical trigger of neuropathic pain. An AT2R-selective antagonist attenuates neuropathic, but not inflammatory pain hypersensitivity in mice, and requires the cell damage-sensing ion channel transient receptor potential family-...

  20. Effects of dextromethorphan and oxycodone on treatment of neuropathic pain in mice.

    Science.gov (United States)

    Yang, Pao-Pao; Yeh, Geng-Chang; Huang, Eagle Yi-Kung; Law, Ping-Yee; Loh, Horace H; Tao, Pao-Luh

    2015-09-22

    Neuropathic pain is a very troublesome and difficult pain to treat. Although opioids are the best analgesics for cancer and surgical pain in clinic, only oxycodone among opioids shows better efficacy to alleviate neuropathic pain. However, many side effects associated with the use of oxycodone render the continued use of it in neuropathic pain treatment undesirable. Hence, we explored whether dextromethorphan (DM, a known N-methyl-D-aspartate receptor antagonist with neuroprotective properties) could potentiate the anti-allodynic effect of oxycodone and underlying mechanisms regarding to glial cells (astrocytes and microglia) activation and proinflammatory cytokines release in a spinal nerve injury (SNL) mice model. Oxycodone produced a dose-dependent anti-allodynic effect. Co-administration of DM at a dose of 10 mg/kg (i.p.) (DM10) which had no anti-allodynic effect by itself enhanced the acute oxycodone (1 mg/kg, s.c.) effect. When the chronic anti-allodynic effects were examined, co-administration of DM10 also significantly enhanced the oxycodone effect at 3 mg/kg. Furthermore, oxycodone decreased SNL-induced activation of glial cells (astrocytes and microglia) and plasma levels of proinflammatory cytokines (IL-6, IL-1β and TNF-α). Co-administration of DM10 potentiated these effects of oxycodone. The combined use of DM with oxycodone may have therapeutic potential for decreasing the effective dose of oxycodone on the treatment of neuropathic pain. Attenuation of the glial activation and proinflammatory cytokines in the spinal cord may be important mechanisms for these effects of DM.

  1. Allergic Inflammation Leads to Neuropathic Pain via Glial Cell Activation.

    Science.gov (United States)

    Yamasaki, Ryo; Fujii, Takayuki; Wang, Bing; Masaki, Katsuhisa; Kido, Mizuho A; Yoshida, Mari; Matsushita, Takuya; Kira, Jun-Ichi

    2016-11-23

    Allergic and atopic disorders have increased over the past few decades and have been associated with neuropsychiatric conditions, such as autism spectrum disorder and asthmatic amyotrophy. Myelitis presenting with neuropathic pain can occur in patients with atopic disorder; however, the relationship between allergic inflammation and neuropathic pain, and the underlying mechanism, remains to be established. We studied whether allergic inflammation affects the spinal nociceptive system. We found that mice with asthma, atopic dermatitis, or atopic diathesis had widespread and significantly more activated microglia and astroglia in the spinal cord than those without atopy, and displayed tactile allodynia. Microarray analysis of isolated microglia revealed a dysregulated phenotype showing upregulation of M1 macrophage markers and downregulation of M2 markers in atopic mice. Among the cell surface protein genes, endothelin receptor type B (EDNRB) was most upregulated. Immunohistochemical analysis revealed that EDNRB expression was enhanced in microglia and astroglia, whereas endothelin-1, an EDNRB ligand, was increased in serum, lungs, and epidermis of atopic mice. No EDNRA expression was found in the spinal cord. Expression of FBJ murine osteosarcoma viral oncogene homolog B was significantly higher in the dorsal horn neurons of asthma mice than nonatopic mice. The EDNRB antagonist BQ788 abolished glial and neural activation and allodynia. We found increased serum endothelin-1 in atopic patients with myelitis and neuropathic pain, and activation of spinal microglia and astroglia with EDNRB upregulation in an autopsied case. These results suggest that allergic inflammation induces diffuse glial activation, influencing the nociceptive system via the EDNRB pathway. The prevalence of allergic disorders has markedly increased over the past few decades. Allergic disorders are associated with neuropsychiatric conditions; however, the relationship between allergic inflammation

  2. Slack channels expressed in sensory neurons control neuropathic pain in mice.

    Science.gov (United States)

    Lu, Ruirui; Bausch, Anne E; Kallenborn-Gerhardt, Wiebke; Stoetzer, Carsten; Debruin, Natasja; Ruth, Peter; Geisslinger, Gerd; Leffler, Andreas; Lukowski, Robert; Schmidtko, Achim

    2015-01-21

    Slack (Slo2.2) is a sodium-activated potassium channel that regulates neuronal firing activities and patterns. Previous studies identified Slack in sensory neurons, but its contribution to acute and chronic pain in vivo remains elusive. Here we generated global and sensory neuron-specific Slack mutant mice and analyzed their behavior in various animal models of pain. Global ablation of Slack led to increased hypersensitivity in models of neuropathic pain, whereas the behavior in models of inflammatory and acute nociceptive pain was normal. Neuropathic pain behaviors were also exaggerated after ablation of Slack selectively in sensory neurons. Notably, the Slack opener loxapine ameliorated persisting neuropathic pain behaviors. In conclusion, Slack selectively controls the sensory input in neuropathic pain states, suggesting that modulating its activity might represent a novel strategy for management of neuropathic pain. Copyright © 2015 the authors 0270-6474/15/351125-11$15.00/0.

  3. 5-HT6 receptor antagonist attenuates the memory deficits associated with neuropathic pain and improves the efficacy of gabapentinoids.

    Science.gov (United States)

    Jayarajan, Pradeep; Nirogi, Ramakrishna; Shinde, Anil; Goura, Venkatesh; Babu, Vuyyuru Arun; Yathavakilla, Sumanth; Bhyrapuneni, Gopinadh

    2015-10-01

    Memory deficit is a co-morbid disorder in patients suffering from neuropathic pain. Gabapentin and pregabalin (gabapentinoids) are among the widely prescribed medications for the treatment of neuropathic pain. Memory loss and sedation are the commonly reported side effects with gabapentinoids. Improving the cognitive functions and attenuating drug-induced side effects may play a crucial role in the management of pain. We evaluated the effects of 5-HT6 receptor antagonists on the memory deficits associated with neuropathy. We also studied the effects of 5-HT6 receptor antagonists on the side effects, and the analgesic effects of gabapentinoids. 5-HT6 receptor antagonists attenuated the cognitive deficits in neuropathic rats. Neuropathic rats co-treated with 5-HT6 receptor antagonist and gabapentinoids showed improvement in memory. 5-HT6 receptor antagonists enhanced the analgesic effects of gabapentinoids but had no effect on the motor side effects. The observed effects may not be due to pharmacokinetic interactions. 5-HT6 receptor antagonist attenuate the cognitive deficits associated with neuropathy, and this effect is also seen when co-treated with gabapentinoids. Since, 5-HT6 antagonists improved the effectiveness of gabapentinoids, reduction in the dosage and frequency of gabapentinoids treatment may reduce the side effects. Combining 5-HT6 receptor antagonist with gabapentinoids may offer a novel treatment strategy for neuropathic pain. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  4. Pain in chemotherapy-induced neuropathy--more than neuropathic?

    Science.gov (United States)

    Geber, Christian; Breimhorst, Markus; Burbach, Berenike; Egenolf, Christina; Baier, Bernhard; Fechir, Marcel; Koerber, Juergen; Treede, Rolf-Detlef; Vogt, Thomas; Birklein, Frank

    2013-12-01

    Chemotherapy-induced neuropathy (CIN) is an adverse effect of chemotherapy. Pain in CIN might comprise neuropathic and nonneuropathic (ie, musculoskeletal) pain components, which might be characterized by pain patterns, electrophysiology, and somatosensory profiling. Included were 146 patients (100 female, 46 male; aged 56 ± 0.8 years) with CIN arising from different chemotherapy regimens. Patients were characterized clinically through nerve conduction studies (NCS) and quantitative sensory testing (QST). Questionnaires for pain (McGill) and anxiety/depression (Hospital Anxiety and Depression Scale) were supplied. Patients were followed-up after 17 days. Large- (61%) and mixed- (35%) fibre neuropathies were more frequent than small-fibre neuropathy (1.4%). The 5 major chemotherapeutic regimens impacted differently on large- but not on small-fibre function and did not predict painfulness. Chronic pain associated with CIN was reported in 41.7%. Painless and painful CIN did not differ in QST profiles or electrophysiological findings, but different somatosensory patterns were found in CIN subgroups (pain at rest [RestP], n = 25; movement-associated pain [MovP], n = 15; both pain characteristics [MovP+RestP], n = 21; or no pain [NonP], n = 85): small-fibre function (cold-detection threshold, CDT: z score: -1.46 ± 0.21, P < 0.01) was most impaired in RestP; mechanical hyperalgesia was exclusively found in MovP (z score: +0.81 ± 0.30, P < 0.05). "Anxiety" discriminated between painful and painless CIN; "CDT" and "anxiety" discriminated between patients with ongoing (RestP) and movement-associated pain (MovP) or pain components (MovP+RestP). The detrimental effect of chemotherapy on large fibres failed to differentiate painful from painless CIN. Patients stratified for musculoskeletal or neuropathic pain, however, differed in psychological and somatosensory parameters. This stratification might allow for the application of a more specific therapy. Copyright © 2013

  5. Neuropathic pain, depressive symptoms, and C-reactive protein in sciatica patients.

    Science.gov (United States)

    Uher, Tomas; Bob, Petr

    2013-03-01

    There is evidence that neuropathic pain component in low back pain (LBP) patients is associated with higher ratings of comorbidities such as depression and anxiety disorders. In line with current findings, the purpose of this clinical study is to examine a hypothesis regarding a relationship of neuropathic pain component, depression, and other psychopathological symptoms in a specific group of LBP patients with sciatica pain. With respect to findings that depression is related to inflammatory changes, and inflammatory mediators may play a role in neuropathic pain generation, we have assessed also serum C-reactive protein (CRP). Results of the present study show that increased neuropathic pain component in sciatica patients is associated with elevated levels of depression, anxiety, alexithymia, and serum CRP levels. In conclusion, results of this study indicate that CRP levels in sciatica patients are closely associated with neuropathic pain.

  6. Application of the capsaicin 8% cutaneous patch in neuropathic pain of the head and face: A case series.

    Science.gov (United States)

    Gaul, Charly; Resch, Sonja

    2015-05-01

    Treatment of neuropathic or neuralgic head and facial pain due to dental, traumatic or surgical nerve lesions or post-herpetic neuropathy is often challenging. We are reporting on four patients with neuropathic pain syndromes successfully treated with a capsaicin 8% patch in the affected area of the head or face. Treatment with the capsaicin 8% patch seems to be effective and safe for application to the facial and head region. The capsaicin 8% patch might be an additional treatment option if first-line treatment with anticonvulsants or antidepressants was ineffective or limited by side effects. © International Headache Society 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  7. Chronic Orofacial Pain: Burning Mouth Syndrome and Other Neuropathic Disorders

    Science.gov (United States)

    Tait, Raymond C; Ferguson, McKenzie; Herndon, Christopher M

    2017-01-01

    Chronic orofacial pain is a symptom associated with a wide range of neuropathic, neurovascular, idiopathic, and myofascial conditions that affect a significant proportion of the population. While the collective impact of the subset of the orofacial pain disorders involving neurogenic and idiopathic mechanisms is substantial, some of these are relatively uncommon. Hence, patients with these disorders can be vulnerable to misdiagnosis, sometimes for years, increasing the symptom burden and delaying effective treatment. This manuscript first reviews the decision tree to be followed in diagnosing any neuropathic pain condition, as well as the levels of evidence needed to make a diagnosis with each of several levels of confidence: definite, probable, or possible. It then examines the clinical literature related to the idiopathic and neurogenic conditions that can occasion chronic orofacial pain, including burning mouth syndrome, trigeminal neuralgia, glossopharyngeal neuralgia, post-herpetic neuralgia, and atypical odontalgia. Temporomandibular disorders also are examined as are other headache conditions, even though they are not neurologic conditions, because they are common and can mimic symptoms of the latter disorders. For each of these conditions, the paper reviews literature regarding incidence and prevalence, physiologic and other contributing factors, diagnostic signs and symptoms, and empirical evidence regarding treatments. Finally, in order to improve the quality and accuracy of clinical diagnosis, as well as the efficiency with which effective treatment is initiated and delivered, criteria are offered that can be instrumental in making a differential diagnosis. PMID:28638895

  8. Chronic Orofacial Pain: Burning Mouth Syndrome and Other Neuropathic Disorders.

    Science.gov (United States)

    Tait, Raymond C; Ferguson, McKenzie; Herndon, Christopher M

    2017-03-01

    Chronic orofacial pain is a symptom associated with a wide range of neuropathic, neurovascular, idiopathic, and myofascial conditions that affect a significant proportion of the population. While the collective impact of the subset of the orofacial pain disorders involving neurogenic and idiopathic mechanisms is substantial, some of these are relatively uncommon. Hence, patients with these disorders can be vulnerable to misdiagnosis, sometimes for years, increasing the symptom burden and delaying effective treatment. This manuscript first reviews the decision tree to be followed in diagnosing any neuropathic pain condition, as well as the levels of evidence needed to make a diagnosis with each of several levels of confidence: definite, probable, or possible. It then examines the clinical literature related to the idiopathic and neurogenic conditions that can occasion chronic orofacial pain, including burning mouth syndrome, trigeminal neuralgia, glossopharyngeal neuralgia, post-herpetic neuralgia, and atypical odontalgia. Temporomandibular disorders also are examined as are other headache conditions, even though they are not neurologic conditions, because they are common and can mimic symptoms of the latter disorders. For each of these conditions, the paper reviews literature regarding incidence and prevalence, physiologic and other contributing factors, diagnostic signs and symptoms, and empirical evidence regarding treatments. Finally, in order to improve the quality and accuracy of clinical diagnosis, as well as the efficiency with which effective treatment is initiated and delivered, criteria are offered that can be instrumental in making a differential diagnosis.

  9. Transcutaneous electrical nerve stimulation (TENS) for neuropathic pain in adults.

    Science.gov (United States)

    Gibson, William; Wand, Benedict M; O'Connell, Neil E

    2017-09-14

    Neuropathic pain, which is due to nerve disease or damage, represents a significant burden on people and society. It can be particularly unpleasant and achieving adequate symptom control can be difficult. Non-pharmacological methods of treatment are often employed by people with neuropathic pain and may include transcutaneous electrical nerve stimulation (TENS). This review supersedes one Cochrane Review 'Transcutaneous electrical nerve stimulation (TENS) for chronic pain' (Nnoaham 2014) and one withdrawn protocol 'Transcutaneous electrical nerve stimulation (TENS) for neuropathic pain in adults' (Claydon 2014). This review replaces the original protocol for neuropathic pain that was withdrawn. To determine the analgesic effectiveness of TENS versus placebo (sham) TENS, TENS versus usual care, TENS versus no treatment and TENS in addition to usual care versus usual care alone in the management of neuropathic pain in adults. We searched CENTRAL, MEDLINE, Embase, PsycINFO, AMED, CINAHL, Web of Science, PEDro, LILACS (up to September 2016) and various clinical trials registries. We also searched bibliographies of included studies for further relevant studies. We included randomised controlled trials where TENS was evaluated in the treatment of central or peripheral neuropathic pain. We included studies if they investigated the following: TENS versus placebo (sham) TENS, TENS versus usual care, TENS versus no treatment and TENS in addition to usual care versus usual care alone in the management of neuropathic pain in adults. Two review authors independently screened all database search results and identified papers requiring full-text assessment. Subsequently, two review authors independently applied inclusion/exclusion criteria to these studies. The same review authors then independently extracted data, assessed for risk of bias using the Cochrane standard tool and rated the quality of evidence using GRADE. We included 15 studies with 724 participants. We found a

  10. Botulinum Toxin Type A for the Treatment of Neuropathic Pain in Neuro-Rehabilitation

    Directory of Open Access Journals (Sweden)

    Domenico Intiso

    2015-06-01

    Full Text Available Pain is a natural protective mechanism and has a warning function signaling imminent or actual tissue damage. Neuropathic pain (NP results from a dysfunction and derangement in the transmission and signal processing along the nervous system and it is a recognized disease in itself. The prevalence of NP is estimated to be between 6.9% and 10% in the general population. This condition can complicate the recovery from stroke, multiple sclerosis, spinal cord lesions, and several neuropathies promoting persistent disability and poor quality of life. Subjects suffering from NP describe it as burning, itching, lancing, and numbness, but hyperalgesia and allodynia represent the most bothersome symptoms. The management of NP is a clinical challenge and several non-pharmacological and pharmacological interventions have been proposed with variable benefits. Botulinum toxin (BTX as an adjunct to other interventions can be a useful therapeutic tool for the treatment of disabled people. Although BTX-A is predominantly used to reduce spasticity in a neuro-rehabilitation setting, it has been used in several painful conditions including disorders characterized by NP. The underlying pharmacological mechanisms that operate in reducing pain are still unclear and include blocking nociceptor transduction, the reduction of neurogenic inflammation by inhibiting neural substances and neurotransmitters, and the prevention of peripheral and central sensitization. Some neurological disorders requiring rehabilitative intervention can show neuropathic pain resistant to common analgesic treatment. This paper addresses the effect of BTX-A in treating NP that complicates frequent disorders of the central and peripheral nervous system such as spinal cord injury, post-stroke shoulder pain, and painful diabetic neuropathy, which are commonly managed in a rehabilitation setting. Furthermore, BTX-A has an effect in relief pain that may characterize less common neurological disorders

  11. Botulinum Toxin Type A for the Treatment of Neuropathic Pain in Neuro-Rehabilitation

    Science.gov (United States)

    Intiso, Domenico; Basciani, Mario; Santamato, Andrea; Intiso, Marta; Di Rienzo, Filomena

    2015-01-01

    Pain is a natural protective mechanism and has a warning function signaling imminent or actual tissue damage. Neuropathic pain (NP) results from a dysfunction and derangement in the transmission and signal processing along the nervous system and it is a recognized disease in itself. The prevalence of NP is estimated to be between 6.9% and 10% in the general population. This condition can complicate the recovery from stroke, multiple sclerosis, spinal cord lesions, and several neuropathies promoting persistent disability and poor quality of life. Subjects suffering from NP describe it as burning, itching, lancing, and numbness, but hyperalgesia and allodynia represent the most bothersome symptoms. The management of NP is a clinical challenge and several non-pharmacological and pharmacological interventions have been proposed with variable benefits. Botulinum toxin (BTX) as an adjunct to other interventions can be a useful therapeutic tool for the treatment of disabled people. Although BTX-A is predominantly used to reduce spasticity in a neuro-rehabilitation setting, it has been used in several painful conditions including disorders characterized by NP. The underlying pharmacological mechanisms that operate in reducing pain are still unclear and include blocking nociceptor transduction, the reduction of neurogenic inflammation by inhibiting neural substances and neurotransmitters, and the prevention of peripheral and central sensitization. Some neurological disorders requiring rehabilitative intervention can show neuropathic pain resistant to common analgesic treatment. This paper addresses the effect of BTX-A in treating NP that complicates frequent disorders of the central and peripheral nervous system such as spinal cord injury, post-stroke shoulder pain, and painful diabetic neuropathy, which are commonly managed in a rehabilitation setting. Furthermore, BTX-A has an effect in relief pain that may characterize less common neurological disorders including post

  12. Continuous brachial plexus block at the cervical level using a posterior approach in the management of neuropathic cancer pain

    NARCIS (Netherlands)

    Vranken, J. H.; van der Vegt, M. H.; Zuurmond, W. W.; Pijl, A. J.; Dzoljic, M.

    2001-01-01

    Neuropathic cancer pain due to tumor growth near the brachial plexus is often treated with a combination of nonsteroidal anti-inflammatory drugs, tricyclic antidepressants, anticonvulsants, and oral or transdermal opioids. We propose placement of a catheter along the brachial plexus using a

  13. Overexpression of GDNF in the uninjured DRG exerts analgesic effects on neuropathic pain following segmental spinal nerve ligation in mice.

    Science.gov (United States)

    Takasu, Kumiko; Sakai, Atsushi; Hanawa, Hideki; Shimada, Takashi; Suzuki, Hidenori

    2011-11-01

    Glial cell line-derived neurotrophic factor (GDNF), a survival-promoting factor for a subset of nociceptive small-diameter neurons, has been shown to exert analgesic effects on neuropathic pain. However, its detailed mechanisms of action are still unknown. In the present study, we investigated the site-specific analgesic effects of GDNF in the neuropathic pain state using lentiviral vector-mediated GDNF overexpression in mice with left fifth lumbar (L5) spinal nerve ligation (SNL) as a neuropathic pain model. A lentiviral vector expressing both GDNF and enhanced green fluorescent protein (EGFP) was constructed and injected into the left dorsal spinal cord, uninjured fourth lumbar (L4) dorsal root ganglion (DRG), injured L5 DRG, or plantar skin of mice. In SNL mice, injection of the GDNF-EGFP-expressing lentivirus into the dorsal spinal cord or uninjured L4 DRG partially but significantly reduced the mechanical allodynia in association with an increase in GDNF protein expression in each virus injection site, whereas injection into the injured L5 DRG or plantar skin had no effects. These results suggest that GDNF exerts its analgesic effects in the neuropathic pain state by acting on the central terminals of uninjured DRG neurons and/or on the spinal cells targeted by the uninjured DRG neurons. This article shows that GDNF exerts its analgesic effects on neuropathic pain by acting on the central terminals of uninjured DRG neurons and/or on the spinal cells targeted by these neurons. Therefore, research focusing on these GDNF-dependent neurons in the uninjured DRG would provide a new strategy for treating neuropathic pain. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.

  14. Combined approaches for the relief of spinal cord injury-induced neuropathic pain.

    Science.gov (United States)

    Gwak, Young S; Kim, Hee Young; Lee, Bong Hyo; Yang, Chae Ha

    2016-04-01

    The adequate treatment of spinal cord injury (SCI)-induced neuropathic pain still remains an unresolved problem. The current medications predominantly used in the SCI-induced neuropathic pain therapy are morphine, anticonvulsants, antidepressants, and antiepileptics, which suggests that psychiatric aspects might be important factors in the treatment of neuropathic pain. It is well documented that the modulation of the sensory events is not a unique way for achieving pain relief. In addition, pain patients still express dissatisfaction and complain of unwanted effects of the medications, suggesting that alternative approaches for the treatment of neuropathic pain are essential. In psychiatry, pain relief represents relaxation and a feeling of comfort and satisfaction, which suggests that cognitive and emotional motivations are important factors in the treatment of neuropathic pain. The comorbidity of chronic pain and psychiatric disorders, which is well recognized, suggests that the effective therapeutic relief for neuropathic pain induced by SCI can be achieved in conjunction with the management of the sensory and psychiatric aspects of patient. In this review, we address the feasibility of a combined acupuncture and pharmacotherapy treatment for the relief of neuropathic pain behavior following SCI. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Implications and mechanism of action of gabapentin in neuropathic pain.

    Science.gov (United States)

    Kukkar, Ankesh; Bali, Anjana; Singh, Nirmal; Jaggi, Amteshwar Singh

    2013-03-01

    Gabapentin is an anti-epileptic agent but now it is also recommended as first line agent in neuropathic pain, particularly in diabetic neuropathy and post herpetic neuralgia. α2δ-1, an auxillary subunit of voltage gated calcium channels, has been documented as its main target and its specific binding to this subunit is described to produce different actions responsible for pain attenuation. The binding to α2δ-1 subunits inhibits nerve injury-induced trafficking of α1 pore forming units of calcium channels (particularly N-type) from cytoplasm to plasma membrane (membrane trafficking) of pre-synaptic terminals of dorsal root ganglion (DRG) neurons and dorsal horn neurons. Furthermore, the axoplasmic transport of α2δ-1 subunits from DRG to dorsal horns neurons in the form of anterograde trafficking is also inhibited in response to gabapentin administration. Gabapentin has also been shown to induce modulate other targets including transient receptor potential channels, NMDA receptors, protein kinase C and inflammatory cytokines. It may also act on supra-spinal region to stimulate noradrenaline mediated descending inhibition, which contributes to its anti-hypersensitivity action in neuropathic pain.

  16. Citalopram, venlafaxine and mirtazapine judged on their merits. Treatment of neuropathic pain

    NARCIS (Netherlands)

    Jurg, R.; Van Roon, E.; Koning, H.; Bruinen, T.

    2002-01-01

    The response of neuropathic pain on treatment with elassie analgesics is limited. As primary or adjuvant therapy treatment with tricyclic antidepressants and anti-epileptics can be iniated. Reports on the efficacy of newer antidepressant for neuropathic pain led to evaluation of the study results

  17. Percutaneous Nerve Stimulation in Chronic Neuropathic Pain Patients due to Spinal Cord Injury: A Pilot Study

    NARCIS (Netherlands)

    Kopsky, D.J.; Ettema, F.W.L.; van der Leeden, M.; Dekker, J.; Stolwijk-Swuste, J.M.

    2014-01-01

    Background: The long-term prognosis for neuropathic pain resolution following spinal cord injury (SCI) is often poor. In many SCI patients, neuropathic pain continues or even worsens over time. Thus, new treatment approaches are needed. We conducted a pilot study to evaluate the feasibility and

  18. Stratifying patients with peripheral neuropathic pain based on sensory profiles

    DEFF Research Database (Denmark)

    Vollert, Jan; Maier, Christoph; Attal, Nadine

    2017-01-01

    In a recent cluster analysis, it has been shown that patients with peripheral neuropathic pain can be grouped into 3 sensory phenotypes based on quantitative sensory testing profiles, which are mainly characterized by either sensory loss, intact sensory function and mild thermal hyperalgesia and...... populations that need to be screened to reach a subpopulation large enough to conduct a phenotype-stratified study. The most common phenotype in diabetic polyneuropathy was sensory loss (83%), followed by mechanical hyperalgesia (75%) and thermal hyperalgesia (34%, note that percentages are overlapping...

  19. Chronic pain in Gaucher disease: skeletal or neuropathic origin?

    Science.gov (United States)

    Devigili, Grazia; De Filippo, Michele; Ciana, Giovanni; Dardis, Andrea; Lettieri, Christian; Rinaldo, Sara; Macor, Daniela; Moro, Alessandro; Eleopra, Roberto; Bembi, Bruno

    2017-08-31

    Pain is one of the most disabling symptoms of Gaucher disease. It is referred by the majority of Gaucher patients and often persists despite long-term enzyme replacement treatment. It has been mainly considered as nociceptive pain secondary to skeletal involvement but it is described even in the absence of bone disease without a clear explanation. In the last years an increasing number of reports have described the presence of neurological manifestation in Gaucher type 1 patients, including subclinical large fibre neuropathy. In our Gaucher clinic we have observed the recurrence of painful symptoms in a group of type 1 Gaucher patients even after a long-term enzyme replacement therapy. A cross-sectional study was designed to investigate the pathophysiology of pain in a cohort of 25 Gaucher patients (13 females, 12 males). Twenty-two patients received enzyme replacement therapy for a period of time ranging from 10 to >20 years, while three were new diagnosis. Pain was classified as bone or neurologic related on the basis of anamnestic data, clinical and electrophysilogical examinations. Intensity and quality of pain were recorded by Douleur Neuropathique en 4 questionnaire and Neuropathic Pain Symptom Inventory. Neuroalgological evaluation, quantitative sensory testing, nerve conduction studies and evaluation of epidermal nerve fibres density were performed. Comorbidities for peripheral neuropathy were excluded. Thirteen patients complained of pain suggestive of neuropathic origin with proximal patchy distribution, six manifested severe pain paroxysmal, nine pinprick hypoesthesia and 17 thermal hypoesthesia. At quantitative sensory testing, all of them showed high cold thresholds with errata sensation (burning instead of cold), paradoxical heat sensation and mechanic hypoesthesia; three patients showed pressure pain hyperalgesia. Epidermal denervation was present in 19 patients, 12 of them with non-length dependent pattern. These results confirm the role of

  20. The effect of Sativex in neuropathic pain and spasticity in spinal cord injury

    DEFF Research Database (Denmark)

    Andresen, Sven Robert; Hansen, Rikke Bod Middelhede; Johansen, Inger Lauge

    2014-01-01

    Introduction: Neuropathic pain and spasticity after spinal cord injury represent significant but still unresolved problems, which cause considerable suffering and reduced quality of life for patients with spinal cord injury. Treatment of neuropathic pain and spasticity is complicated and patients...... often receive incomplete relief from present available and recommended treatment. Cannabinoids has shown efficacy on both neuropathic pain and spasticity in patients with spinal cord injury, but the studies one the topic has been too small to make a general conclusion for patients with spinal cord...... injury. Aims: To investigate the effect of Sativex (cannabinoid agonist given as an oral mucosal spray), on neuropathic pain and spasticity in patients with spinal cord injury. Methods: A randomized, double-blind, placebo-controlled crossover study. We will include 30 patients with neuropathic pain...

  1. Wen-Luo-Tong Prevents Glial Activation and Nociceptive Sensitization in a Rat Model of Oxaliplatin-Induced Neuropathic Pain.

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    Deng, Bo; Jia, Liqun; Pan, Lin; Song, Aiping; Wang, Yuanyuan; Tan, Huangying; Xiang, Qing; Yu, Lili; Ke, Dandan

    2016-01-01

    One of the main dose-limiting complications of the chemotherapeutic agent oxaliplatin (OXL) is painful neuropathy. Glial activation and nociceptive sensitization may be responsible for the mechanism of neuropathic pain. The Traditional Chinese Medicine (TCM) Wen-luo-tong (WLT) has been widely used in China to treat chemotherapy induced neuropathic pain. However, there is no study on the effects of WLT on spinal glial activation induced by OXL. In this study, a rat model of OXL-induced chronic neuropathic pain was established and WLT was administrated. Pain behavioral tests and morphometric examination of dorsal root ganglia (DRG) were conducted. Glial fibrillary acidic protein (GFAP) immunostaining was performed, glial activation was evaluated, and the excitatory neurotransmitter substance P (SP) and glial-derived proinflammatory cytokine tumor necrosis factor-α (TNF-α) were analyzed. WLT treatment alleviated OXL-induced mechanical allodynia and mechanical hyperalgesia. Changes in the somatic, nuclear, and nucleolar areas of neurons in DRG were prevented. In the spinal dorsal horn, hypertrophy and activation of GFAP-positive astrocytes were averted, and the level of GFAP mRNA decreased significantly. Additionally, TNF-α mRNA and protein levels decreased. Collectively, these results indicate that WLT reversed both glial activation in the spinal dorsal horn and nociceptive sensitization during OXL-induced chronic neuropathic pain in rats.

  2. Fear of pain in children and adolescents with neuropathic pain and CRPS

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    Simons, Laura E.

    2015-01-01

    A significant proportion of children and adolescents with chronic pain endorse elevated pain-related fear. Pain-related fear is associated with high levels of disability, depressive symptoms, and school impairment. Due to faulty nerve signaling, individuals with neuropathic pain and CRPS may be more prone to develop pain-related fear as they avoid use of and neglect the affected body area(s), resulting in exacerbated symptoms, muscle atrophy, maintenance of pain signaling, and ongoing pain-related disability. Not surprisingly, effective treatments for elevated pain-related fears involve exposure to previously avoided activities to down-regulate incorrect pain signaling. In the context of intensive interdisciplinary pain treatment of youth with neuropathic pain, decreasing pain-related fear is associated with improved physical and psychological functioning, while high initial pain-related fear is a risk factor for less treatment responsiveness. An innovative approach to targeting pain-related fear as well as evidence of a neural response to treatment involving decoupling of the amygdala with key fear circuits in youth with CRPS suggest breakthroughs in our ability to ameliorate these issues. PMID:26785161

  3. Surgical experience of laparoscopic retroperitoneal triple neurectomy for a patient with chronic neuropathic inguinodynia

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    Masato Narita

    2017-01-01

    Conclusions: Laparoscopic retroperitoneal triple neurectomy is useful for treating refractory neuropathic pain. The diagnosis of neuropathic pain via thorough preoperative assessment is vital for procedure success because the procedure would not be effective for other types of pain.

  4. Natural history and outcome of 200 outpatients with classical trigeminal neuralgia treated with carbamazepine or oxcarbazepine in a tertiary centre for neuropathic pain

    Science.gov (United States)

    2014-01-01

    Background The guidelines on trigeminal neuralgia management that have been agreed and jointly published by the American Academy of Neurology and the European Federation of Neurological Societies recommend carbamazepine (CBZ) and oxcarbazepine (OXC) as the first-choice medical treatments in patients with trigeminal neuralgia (TN). The aim of this retrospective study was to analyze the natural history of classical trigeminal neuralgia in a large cohort of patients, focusing on drug responsiveness, side effects related to CBZ and OXC, and changes in pain characteristics during the course of disease. Findings We selected the last 100 consecutive patients with typical TN who began treatment with CBZ and the last 100 with OXC. All had MRI scans and a complete neurophysiological study of trigeminal reflexes. Among them, 22 were excluded on the basis of neuroradiological or neurophysiological investigations, to avoid the inclusion of patients with possible secondary TN. The initial number of responders was 98% with CBZ with a median dose of 600 mg (range 200–1200), and of 94% with OXC, with a median dose of 1200 mg (range 600–1800). In a mean period of 8.6 months, 27% of responders to CBZ incurred in undesired effects to a level that caused interruption of treatment or a dosage reduction to an unsatisfactory level. In a mean period of 13 months, the same occurred to 18% of responders to OXC. Among patients who had a good initial response, only 3 patients with CBZ and 2 with OXC developed late resistance. During the course of disease, paroxysms worsened in intensity in 3% of patients, and paroxysms duration increased in 2%. We did not observe the onset of a clinically manifest sensory deficit at any time in any patient. Conclusions Unlike common notion, in our large patient sample the worsening of pain with time and the development of late resistance only occurred in a very small minority of patients. CBZ and OXC were confirmed to be efficacious in a large majority

  5. The effects of music therapy on pain in patients with neuropathic pain.

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    Korhan, Esra Akın; Uyar, Meltem; Eyigör, Can; Hakverdioğlu Yönt, Gülendam; Çelik, Serkan; Khorshıd, Leyla

    2014-03-01

    The aim of this study was to investigate the effect of relaxing music on pain intensity in patients with neuropathic pain. A quasi-experimental study, repeated measures design was used. Thirty patients, aged 18-70 years, with neuropathic pain and hospitalized in an Algology clinic were identified as a convenience sample. Participants received 60 minutes of music therapy. Classical Turkish music was played to patients using a media player (MP3) and headphones. Participants had pain scores taken immediately before the intervention and at the 30th and 60th minutes of the intervention. Data were collected over a 6-month period in 2012. The patients' mean pain intensity scores were reduced by music, and that decrease was progressive over the 30th and 60th minutes of the intervention, indicating a cumulative dose effect. The results of this study implied that the inclusion of music therapy in the routine care of patients with neuropathic pain could provide nurses with an effective practice for reducing patients' pain intensity. Copyright © 2014 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  6. Alterations in the Anandamide Metabolism in the Development of Neuropathic Pain

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    Natalia Malek

    2014-01-01

    Full Text Available Endocannabinoids (EC, particularly anandamide (AEA, released constitutively in pain pathways might be accountable for the inhibitory effect on nociceptors. Pathogenesis of neuropathic pain may reflect complex remodeling of the dorsal root ganglia (DRGs and spinal cord EC system. Multiple pathways involved both in the biosynthesis and degradation of AEA have been suggested. We investigated the local synthesis and degradation features of AEA in DRGs and spinal cord during the development and maintenance of pain in a model of chronic constriction injury (CCI. All AEA synthesis and degradation enzymes are present on the mRNA level in DRGs and lumbar spinal cord of intact as well as CCI-treated animals. Deregulation of EC system components was consistent with development of pain phenotype at days 3, 7, and 14 after CCI. The expression levels of enzymes involved in AEA degradation was significantly upregulated ipsilateral in DRGs and spinal cord at different time points. Expression of enzymes of the alternative, sPLA2-dependent and PLC-dependent, AEA synthesis pathways was elevated in both of the analyzed structures at all time points. Our data have shown an alteration of alternative AEA synthesis and degradation pathways, which might contribute to the variation of AEA levels and neuropathic pain development.

  7. Pharmacologic management of neuropathic pain: Evidence-based recommendations

    DEFF Research Database (Denmark)

    Dworkin, Robert H.; O'Connor, Alec B.; Backonja, Miroslav

    2007-01-01

    Patients with neuropathic pain (NP) are challenging to manage and evidence-based clinical recommendations for pharmacologic management are needed. Systematic literature reviews, randomized clinical trials, and existing guidelines were evaluated at a consensus meeting. Medications were considered...... and pregabalin), and topical lidocaine. Opioid analgesics and tramadol are recommended as generally second-line treatments that can be considered for first-line use in select clinical circumstances. Other medications that would generally be used as third-line treatments but that could also be used as second......, and whether prompt onset of pain relief is necessary. To date, no medications have demonstrated efficacy in lumbosacral radiculopathy, which is probably the most common type of NP. Long-term studies, head-to-head comparisons between medications, studies involving combinations of medications, and RCTs...

  8. Diagnosis of Neuropathic Components in Patients with Back Pain Before and After Surgery.

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    Lee, Y-J; Koch, E M W; Breidebach, J B; Bornemann, R; Wirtz, D C; Pflugmacher, R

    2016-12-01

    Background: The perception of back pain subjective is hard for physicians to measure. For this reason, questionnaires are an important instrument to evaluate the pain 1. The main point of this study was to verify differentiation of pain symptoms in patients with different pain mechanisms. The most important parameter was the PainDetect questionnaire, which can differentiate between nociceptive and neuropathic pain. Additional parameters were measured before and after surgery to characterise pain symptoms in detail. Material and Methods: We selected patients with diagnosed vertebral compression fracture, herniated disc or with spinal cord compression. To characterise the preoperative condition on admittance, we collected the data from the physical examination, as well as clinical data, including X-ray, CT and MRI. To characterise the pain, we used the painDetect questionnaire, the Oswestry Index questionnaire (ODI) and the visual analogue scale (VAS). Depending on the diagnosis, patients were treated by surgery (radiofrequency kyphoplasty, nucleotomy, spondylodesis). At 2 to 3 days and 6 months after surgery, we repeated the questionnaire and compared the results with those before the operation. Data on patient satisfaction and adverse events were also collected. Results: This study included 62 patients with vertebral compression fracture (group 1: VBF, 89 % female, mean age 71 years) and 77 patients with herniated disc or spinal cord compression (group 2: non-VBF, 55 % female, mean age 53 years). There was no difference between both groups in preoperative pain intensity (acute, maximum, average): median ordinal scale 0 to 10; group 1: 6, 8, 7; group 2: 6, 9, 7. The total score in the painDetect questionnaire differed significantly between the two groups (median group 1 = 9, group 2 = 17; effect size r = 0.5; p = 0.000). The existence of neuropathic pain was presumed (> 90 %) in 3 % of the patients in group 1 and in 13 % of patients it

  9. Conditioned Medium of Bone Marrow-Derived Mesenchymal Stromal Cells as a Therapeutic Approach to Neuropathic Pain: A Preclinical Evaluation

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    Kelly Barbosa Gama

    2018-01-01

    Full Text Available Neuropathic pain is a type of chronic pain caused by injury or dysfunction of the nervous system, without effective therapeutic approaches. Mesenchymal stromal cells (MSCs, through their paracrine action, have great potential in the treatment of this syndrome. In the present study, the therapeutic potential of MSC-derived conditioned medium (CM was investigated in a mouse model of neuropathic pain induced by partial sciatic nerve ligation (PSL. PSL mice were treated by endovenous route with bone marrow-derived MSCs (1 × 106, CM, or vehicle. Gabapentin was the reference drug. Twelve hours after administration, neuropathic mice treated with CM exhibited an antinociceptive effect that was maintained throughout the evaluation period. MSCs also induced nonreversed antinociception, while gabapentin induced short-lasting antinociception. The levels of IL-1β, TNF-α, and IL-6 were reduced, while IL-10 was enhanced on sciatic nerve and spinal cord by treatment with CM and MSCs. Preliminary analysis of the CM secretome revealed the presence of growth factors and cytokines likely involved in the antinociception. In conclusion, the CM, similar to injection of live cells, produces a powerful and long-lasting antinociceptive effect on neuropathic pain, which is related with modulatory properties on peripheral and central levels of cytokines involved with the maintenance of this syndrome.

  10. The effect of low-frequency TENS in the treatment of neuropathic pain in patients with spinal cord injury.

    Science.gov (United States)

    Celik, E C; Erhan, B; Gunduz, B; Lakse, E

    2013-04-01

    Prospective, randomized and controlled study. The aim of the study was to investigate the effect of low-frequency transcutaneous electrical nerve stimulation (LF-TENS) in the treatment of neuropathic pain in patients with spinal cord injury (SCI). A total of 33 SCI patients with neuropathic pain were included in the study. History, duration, localization and characteristics of pain were recorded. Visual analog scale (VAS) was used to investigate the effect of LF-TENS four times during the day. Patients were randomly assigned to study and control groups. The study group was treated with 30 min of LF-TENS daily for 10 days while the placebo group with 30 min of sham TENS. The mean age of the patients was 36.55±10.36 years. Out of 33 patients, 7 were tetraplegic and 26 were paraplegic. Twenty-three patients had complete SCI while 10 patients had incomplete injuries. Two groups were similar with respect to age, gender, duration, level and severity of injury. In the LF-TENS treatment group, a statistically significant reduction of the VAS values was observed, however, such an effect was not evident in the control group. This study revealed that in treatment of neuropathic pain of SCI patients, LF-TENS may be effective. This article presents LF-TENS may effectively complement pharmacological treatment in patients with SCI and neuropathic pain.

  11. The α2δ-1-NMDA Receptor Complex Is Critically Involved in Neuropathic Pain Development and Gabapentin Therapeutic Actions

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    Jinjun Chen

    2018-02-01

    Full Text Available α2δ-1, commonly known as a voltage-activated Ca2+ channel subunit, is a binding site of gabapentinoids used to treat neuropathic pain and epilepsy. However, it is unclear how α2δ-1 contributes to neuropathic pain and gabapentinoid actions. Here, we show that Cacna2d1 overexpression potentiates presynaptic and postsynaptic NMDAR activity of spinal dorsal horn neurons to cause pain hypersensitivity. Conversely, Cacna2d1 knockdown or ablation normalizes synaptic NMDAR activity increased by nerve injury. α2δ-1 forms a heteromeric complex with NMDARs in rodent and human spinal cords. The α2δ-1-NMDAR interaction predominantly occurs through the C terminus of α2δ-1 and promotes surface trafficking and synaptic targeting of NMDARs. Gabapentin or an α2δ-1 C terminus-interfering peptide normalizes NMDAR synaptic targeting and activity increased by nerve injury. Thus, α2δ-1 is an NMDAR-interacting protein that increases NMDAR synaptic delivery in neuropathic pain. Gabapentinoids reduce neuropathic pain by inhibiting forward trafficking of α2δ-1-NMDAR complexes.

  12. Evaluation of the Effect of Duration on the Efficacy of Pulsed Radiofrequency in an Animal Model of Neuropathic Pain.

    Science.gov (United States)

    Ramzy, Eiad A; Khalil, Khaled I; Nour, Eman M; Hamed, Mohammed F; Taha, Mohamed A

    2018-03-01

    Pulsed radiofrequency (PRF) is increasingly used in clinical practice, especially in neuropathic pain disorders. Although PRF is not new to clinical use, there are significant gaps in knowledge regarding its effectiveness. The current study was conducted to evaluate the effect of duration of application of PRF on its analgesic efficacy in improvement of neuropathic pain. A randomized experimental trial. An animal research facility at the College of Veterinary Medicine at Mansoura University in Egypt. Chronic constriction of the sciatic nerve of 36 male Sprague-Dawley rats was performed to induce neuropathic pain. The rats were divided into 6 groups (6 rats each) in which PRF was applied for 2, 4, 6, or 8 minutes or not at all. In one group, RF cannula was applied without performing PRF intervention. The pain was assessed through observation of resting paw posture (RPP) at 3, 10, and 21 days. Nerve damage was assessed by histopathological evaluation of the sciatic nerve. Immunohistochemical localization of proinflammatory cytokines (interleukin 6 [IL-6] and tumor necrosis factor alpha [TNF-alpha]) was also done. RPP was improved in rats treated with PRF. This improvement was significant only in rats treated for 8 minutes. Increased duration for PRF application was associated with a significant decrease in IL-6 and TNF-alpha contents in all groups when compared with the control group. Histopathological evaluation of the constricted sciatic nerve revealed no statistical significance among the different study groups. The study was limited by the lack of measurement of other inflammatory markers that may help elucidate other relevant mechanisms. Increased duration of PRF application resulted in better analgesic efficacy without any increase in tissue injury in an animal model of neuropathic pain. This effect may be attributed to decreased production of pro-inflammatory cytokines. Pulsed radiofrequency, analgesic, rats, sciatic nerve, duration, neuropathic pain.

  13. Parameter Optimization Analysis of Prolonged Analgesia Effect of tDCS on Neuropathic Pain Rats

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    Hui-Zhong Wen

    2017-06-01

    Full Text Available Background: Transcranial direct current stimulation (tDCS is widely used to treat human nerve disorders and neuropathic pain by modulating the excitability of cortex. The effectiveness of tDCS is influenced by its stimulation parameters, but there have been no systematic studies to help guide the selection of different parameters.Objective: This study aims to assess the effects of tDCS of primary motor cortex (M1 on chronic neuropathic pain in rats and to test for the optimal parameter combinations for analgesia.Methods: Using the chronic neuropathic pain models of chronic constriction injury (CCI, we measured pain thresholds before and after anodal-tDCS (A-tDCS using different parameter conditions, including stimulation intensity, stimulation time, intervention time and electrode located (ipsilateral or contralateral M1 of the ligated paw on male/female CCI models.Results: Following the application of A-tDCS over M1, we observed that the antinociceptive effects were depended on different parameters. First, we found that repetitive A-tDCS had a longer analgesic effect than single stimulus, and both ipsilateral-tDCS (ip-tDCS and contralateral-tDCS (con-tDCS produce a long-lasting analgesic effect on neuropathic pain. Second, the antinociceptive effects were intensity-dependent and time-dependent, high intensities worked better than low intensities and long stimulus durations worked better than short stimulus durations. Third, timing of the intervention after injury affected the stimulation outcome, early use of tDCS was an effective method to prevent the development of pain, and more frequent intervention induced more analgesia in CCI rats, finally, similar antinociceptive effects of con- and ip-tDCS were observed in both sexes of CCI rats.Conclusion: Optimized protocols of tDCS for treating antinociceptive effects were developed. These findings should be taken into consideration when using tDCS to produce analgesic effects in clinical

  14. Diagnosis and management of neuropathic pain: a balanced approach to treatment.

    Science.gov (United States)

    Nicholson, Bruce D

    2003-12-01

    To provide nurse practitioners with a conceptual framework from which to diagnose and manage chronic neuropathic pain, specifically postherpetic neuralgia (PHN). A current review of the available treatment options for the management of neuropathic pain and PHN is provided. A comprehensive literature review was conducted. Clinical articles, meta-analyses, and reviews were selected for their relevance to the diagnosis and management of chronic neuropathic pain and PHN. Managing patients with chronic neuropathic pain is a common clinical challenge due to variability in individual symptoms, mechanisms, and treatment responses. In patients with PHN, a balanced treatment approach focusing on efficacy, safety, and tolerability is recommended. With appropriate treatment, most patients are able to achieve clinically significant relief from neuropathic pain. Diagnosis and management of neuropathic pain syndromes is challenging. Because of the complexity of chronic pain, successful long-term treatment can be especially difficult (Nicholson, 2003b). While most acute pain is nociceptive (i.e., a response to noxious stimuli), chronic pain can be nociceptive, neuropathic, or of mixed origin. PHN is a chronic pain syndrome that can last for years, causing physical and social disability and psychological distress (Kanazi, 2000). Despite major recent advances in the treatment of PHN, many patients remain refractory to current therapy (Dworkin, 2003). For practicing clinicians, including nurse practitioners, viewing pain as a disease rather than a symptom is the first step towards its successful management. Understanding the pathophysiology of chronic pain and emerging treatment paradigms for the management of neuropathic pain and PHN is critical to optimal care.

  15. Combined Effects of Bee Venom Acupuncture and Morphine on Oxaliplatin-Induced Neuropathic Pain in Mice

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    Woojin Kim

    2016-01-01

    Full Text Available Oxaliplatin, a chemotherapeutic drug for colorectal cancer, induces severe peripheral neuropathy. Bee venom acupuncture (BVA has been used to attenuate pain, and its effect is known to be mediated by spinal noradrenergic and serotonergic receptors. Morphine is a well-known opioid used to treat different types of pain. Here, we investigated whether treatment with a combination of these two agents has an additive effect on oxaliplatin-induced neuropathic pain in mice. To assess cold and mechanical allodynia, acetone and von Frey filament tests were used, respectively. Significant allodynia signs were observed three days after an oxaliplatin injection (6 mg/kg, i.p.. BVA (0.25, 1, and 2.5 mg/kg, s.c., ST36 or morphine (0.5, 2, and 5 mg/kg, i.p. alone showed dose-dependent anti-allodynic effects. The combination of BVA and morphine at intermediate doses showed a greater and longer effect than either BVA or morphine alone at the highest dose. Intrathecal pretreatment with the opioidergic (naloxone, 20 μg or 5-HT3 (MDL-72222, 15 μg receptor antagonist, but not with α2-adrenergic (idazoxan, 10 μg receptor antagonist, blocked this additive effect. Therefore, we suggest that the combination effect of BVA and morphine is mediated by spinal opioidergic and 5-HT3 receptors and this combination has a robust and enduring analgesic action against oxaliplatin-induced neuropathic pain.

  16. Combined Effects of Bee Venom Acupuncture and Morphine on Oxaliplatin-Induced Neuropathic Pain in Mice.

    Science.gov (United States)

    Kim, Woojin; Kim, Min Joon; Go, Donghyun; Min, Byung-Il; Na, Heung Sik; Kim, Sun Kwang

    2016-01-22

    Oxaliplatin, a chemotherapeutic drug for colorectal cancer, induces severe peripheral neuropathy. Bee venom acupuncture (BVA) has been used to attenuate pain, and its effect is known to be mediated by spinal noradrenergic and serotonergic receptors. Morphine is a well-known opioid used to treat different types of pain. Here, we investigated whether treatment with a combination of these two agents has an additive effect on oxaliplatin-induced neuropathic pain in mice. To assess cold and mechanical allodynia, acetone and von Frey filament tests were used, respectively. Significant allodynia signs were observed three days after an oxaliplatin injection (6 mg/kg, i.p.). BVA (0.25, 1, and 2.5 mg/kg, s.c., ST36) or morphine (0.5, 2, and 5 mg/kg, i.p.) alone showed dose-dependent anti-allodynic effects. The combination of BVA and morphine at intermediate doses showed a greater and longer effect than either BVA or morphine alone at the highest dose. Intrathecal pretreatment with the opioidergic (naloxone, 20 μg) or 5-HT3 (MDL-72222, 15 μg) receptor antagonist, but not with α2 adrenergic (idazoxan, 10 μg) receptor antagonist, blocked this additive effect. Therefore, we suggest that the combination effect of BVA and morphine is mediated by spinal opioidergic and 5-HT3 receptors and this combination has a robust and enduring analgesic action against oxaliplatin-induced neuropathic pain.

  17. Pain-related psychological distress, self-rated health and significance of neuropathic pain in Danish soldiers injured in Afghanistan

    DEFF Research Database (Denmark)

    Duffy, J R; Warburg, Finn; Koelle, S-F T

    2015-01-01

    BACKGROUND: Pain and mental health concerns are prevalent among veterans. While the majority of research has focused on chronic pain as an entity, there has been little work directed towards investigating the role of neuropathic pain in relation to psychological comorbidity. As such, we...... hypothesised that participants with signs of neuropathic pain would report higher levels of psychological distress and diminished self-rated health compared to those without a neuropathic component. METHODS: A retrospective review of standardised questionnaires (PainDETECT Questionnaire, Post-traumatic Stress...... pain. RESULTS: Fifty-three participants were included. The Post-traumatic Stress Disorder Checklist-Civilian score was in median (interquartile range) 26 (22-31), the Hospital Anxiety and Depression Scale score was 4 (2-6.5) and 2 (1-5) for anxiety and depression respectively. Evidence of neuropathic...

  18. Tanshinone IIA attenuates neuropathic pain via inhibiting glial activation and immune response.

    Science.gov (United States)

    Cao, Fa-Le; Xu, Min; Wang, Yan; Gong, Ke-Rui; Zhang, Jin-Tao

    2015-01-01

    Neuropathic pain, characterized by spontaneous pain, hyperalgesia and allodynia, is a devastating neurological disease that seriously affects patients' quality of life. We have previously shown that tanshinone IIA (TIIA), an important lipophilic component of Danshen, had significant anti-nociceptive effect in somatic and visceral pain, it is surprisingly noted that few pharmacological studies have been carried out to explore the possible analgesic action of TIIA on neuropathic pain and the underlying mechanisms. Therefore, in the present study, by using spinal nerve ligation (SNL) pain model, the antinociceptive and antihyperalgesic effects of TIIA on neuropathic pain were evaluated by intraperitoneal administration in rats. The results indicated that TIIA dose-dependently inhibited SNL-induced mechanical hyperalgesia. As revealed by OX42 levels, TIIA effectively repressed the activation of spinal microglial activation in SNL-induced neuropathic pain. Meanwhile, TIIA also decreased the expressions of inflammatory cytokines TNF-α and IL-1β in the spinal cord. Furthermore, TIIA inhibited oxidative stress by significantly rescuing the superoxide dismutase (SOD) activity and decreasing the malondialdehyde (MDA). Moreover, TIIA depressed SNL-induced MAPKs activation in spinal cord. Taken together, our study provides evidence that TIIA inhibited SNL-induced neuropathic pain through depressing microglial activation and immune response by the inhibition of mitogen-activated protein kinases (MAPKs) pathways. Our findings suggest that TIIA might be a promising agent in the treatment of neuropathic pain. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. TMEM16F Regulates Spinal Microglial Function in Neuropathic Pain States

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    Laura Batti

    2016-06-01

    Full Text Available Neuropathic pain is a widespread chronic pain state that results from injury to the nervous system. Spinal microglia play a causative role in the pathogenesis of neuropathic pain through secretion of growth factors and cytokines. Here, we investigated the contribution of TMEM16F, a protein that functions as a Ca2+-dependent ion channel and a phospholipid scramblase, to microglial activity during neuropathic pain. We demonstrate that mice with a conditional ablation of TMEM16F in microglia do not develop mechanical hypersensitivity upon nerve injury. In the absence of TMEM16F, microglia display deficits in process motility and phagocytosis. Moreover, loss of GABA immunoreactivity upon injury is spared in TMEM16F conditional knockout mice. Collectively, these data indicate that TMEM16F is an essential component of the microglial response to injury and suggest the importance of microglial phagocytosis in the pathogenesis of neuropathic pain.

  20. A Single Sub-anesthetic Dose of Ketamine Relieves Depression-like Behaviors Induced by Neuropathic Pain in Rats

    Science.gov (United States)

    Wang, Jing; Goffer, Yossef; Xu, Duo; Tukey, David S.; Shamir, D. B.; Eberle, Sarah E.; Zou, Anthony H.; Blanck, Thomas J.J.; Ziff, Edward B.

    2011-01-01

    Background Chronic pain is associated with depression. In rodents, pain is often assessed by sensory hypersensitivity, which does not sufficiently measure affective responses. Low-dose ketamine has been used to treat both pain and depression, but it is not clear whether ketamine can relieve depression associated with chronic pain and whether this antidepressant effect depends on its anti-nociceptive properties. Methods We examined whether the spared nerve injury (SNI) model of neuropathic pain induces depressive behavior in rats, using sucrose preference test and forced swim test, and tested whether a subanesthetic dose of ketamine treats SNI-induced depression. Results SNI-treated rats, compared with control, showed decreased sucrose preference (0.719 ± 0.068 (mean ± SEM) vs. 0.946 ± 0.010) and enhanced immobility in the forced swim test (107.3 ± 14.6s vs. 56.2 ± 12.5s). Further, sham-operated rats demonstrated depressive behaviors in the acute postoperative period (0.790 ± 0.062 on postoperative day 2). A single subanesthetic dose of ketamine (10mg/kg) did not alter SNI-induced hypersensitivity; however, it treated SNI-associated depression-like behaviors (0.896 ± 0.020 for ketamine vs. 0.663 ± 0.080 for control 1 day after administration; 0.858 ± 0.017 for ketamine vs. 0.683 ± 0.077 for control 5 days after administration). Conclusions Chronic neuropathic pain leads to depression-like behaviors. The postoperative period also confers vulnerability to depression, possibly due to acute pain. Sucrose preference test and forced swim test may be used to compliment sensory tests for assessment of pain in animal studies. Low-dose ketamine can treat depression-like behaviors induced by chronic neuropathic pain. PMID:21934410

  1. Role of microglia in neuropathic pain, postoperative pain, and morphine tolerance

    Science.gov (United States)

    Wen, Yeong-Ray; Tan, Ping-Heng; Cheng, Jen-Kun; Liu, Yen-Chin; Ji, Ru-Rong

    2011-01-01

    Management of chronic pain such as nerve injury-induced neuropathic pain associated with diabetic neuropathy, viral infection, and cancer is a real clinical challenge. Major surgeries such as breast and thoracic surgery, leg amputation, and coronary artery bypass surgery also lead to chronic pain in 10–50% of individuals after acute postoperative pain, in part due to surgery-induced nerve injury. Current treatments mainly focus on blocking neurotransmission in the pain pathway and have only resulted in limited success. Ironically, chronic opioid exposure may lead to paradoxical pain. Development of effective therapeutic strategies requires a better understanding of cellular mechanisms underlying the pathogenesis of neuropathic pain. An important progress in pain research points to important role of microglial cells in the development of chronic pain. Spinal cord microglia are strongly activated after nerve injury, surgical incision, and chronic opioid exposure. Increasing evidence suggests that under all these conditions the activated microglia not only exhibit increased expression of microglial markers CD11b and Iba1 but also display elevated phosphorylation of p38 MAP kinase. Inhibition of spinal cord p38 has been shown to attenuate neuropathic pain and postoperative pain, as well as morphine-induced antinociceptive tolerance. Activation of p38 in spinal microglia results in increased synthesis and release of the neurotrophin BDNF and the proinflammatory cytokines IL-1β, IL-6, and TNF-α. These microglia-released mediators can powerfully modulate spinal cord synaptic transmission, leading to increased excitability of dorsal horn neurons, i.e. central sensitization, in part via suppressing inhibitory synaptic transmission. We review the studies that support the pronociceptive role of microglia in conditions of neuropathic pain, post-surgical pain, and opioid tolerance. Some of these studies have been accomplished by four Taiwanese anesthesiologists who are also

  2. The Impact of Enrollment in a Specialized Interdisciplinary Neuropathic Pain Clinic

    Directory of Open Access Journals (Sweden)

    Alex Garven

    2011-01-01

    Full Text Available BACKGROUND: Chronic pain clinics have been created because of the increasing recognition of chronic pain as a very common, debilitating condition that requires specialized care. Neuropathic pain (NeP is a multifaceted, specialized form of chronic pain that often requires input from multiple disciplines for assessment and management.

  3. The clinical characteristics of neuropathic pain in patients with spinal cord injury.

    Science.gov (United States)

    Celik, E C; Erhan, B; Lakse, E

    2012-08-01

    The aim of the study was to evaluate the characteristics of neuropathic pain and observe intensity alterations in pain with regard to time during the day in spinal cord injury (SCI) patients. A total of 50 SCI patients (M/F, 40/10; mean age, 35±12 years) with at-level and below-level neuropathic pain were included in the study. All patients were examined and classified according to the ASIA/ISCoS 2002 International Neurologic Examination and Classification Standards. The history, duration, localization and characteristics of the pain were recorded. Neuropathic pain of patients was evaluated with the McGill-Melzack Pain Questionnaire and LANSS (Leeds Assessment of Neuropathic Symptoms and Signs) Pain Scale. Visual analog scale (VAS) was used to measure the severity of pain four times during the day. Quality of life was analyzed with Short Form 36. Out of 50 patients, 10 were tetraplegic and 40 were paraplegic. In all, 28 patients had motor and sensory complete injuries (AIS A), whereas 22 patients had sensory incomplete (AIS B, C and D) injuries. The most frequently used words to describe neuropathic pain were throbbing, tiring, hot and tingling. Pain intensity was significantly higher in the night than in the evening, noon and morning (PNeuropathic pain is a serious complaint in SCI patients and affects their quality of life. Neuropathic pain intensity was higher in the night hours than other times of day. This situation reinforces the need for a continued research and education on neuropathic pain in SCI.

  4. Orofacial neuropathic pain induced by oxaliplatin: downregulation of KCNQ2 channels in V2 trigeminal ganglion neurons and treatment by the KCNQ2 channel potentiator retigabine.

    Science.gov (United States)

    Ling, Jennifer; Erol, Ferhat; Viatchenko-Karpinski, Viacheslav; Kanda, Hirosato; Gu, Jianguo G

    2017-01-01

    Neuropathic pain induced by chemotherapy drugs such as oxaliplatin is a dose-limiting side effect in cancer treatment. The mechanisms underlying chemotherapy-induced neuropathic pain are not fully understood. KCNQ2 channels are low-threshold voltage-gated K+ channels that play a role in controlling neuronal excitability. Downregulation of KCNQ2 channels has been proposed to be an underlying mechanism of sensory hypersensitivity that leads to neuropathic pain. However, it is currently unknown whether KCNQ channels may be downregulated by chemotherapy drugs in trigeminal ganglion neurons to contribute to the pathogenesis of chemotherapy-induced orofacial neuropathic pain. In the present study, mechanical sensitivity in orofacial regions is measured using the operant behavioral test in rats treated with oxaliplatin. Operant behaviors in these animals show the gradual development of orofacial neuropathic pain that manifests with orofacial mechanical allodynia. Immunostaining shows strong KCNQ2 immunoreactivity in small-sized V2 trigeminal ganglion neurons in controls, and the numbers of KCNQ2 immunoreactivity positive V2 trigeminal ganglion neurons are significantly reduced in oxaliplatin-treated animals. Immunostaining is also performed in brainstem and shows strong KCNQ2 immunoreactivity at the trigeminal afferent central terminals innervating the caudal spinal trigeminal nucleus (Vc) in controls, but the KCNQ2 immunoreactivity intensity is significantly reduced in oxaliplatin-treated animals. We further show with the operant behavioral test that oxaliplatin-induced orofacial mechanical allodynia can be alleviated by the KCNQ2 potentiator retigabine. Taken together, these findings suggest that KCNQ2 downregulation may be a cause of oxaliplatin-induced orofacial neuropathic pain and KCNQ2 potentiators may be useful for alleviating the neuropathic pain.

  5. The anatomical relationship of the superficial radial nerve and the lateral antebrachial cutaneous nerve: A possible factor in persistent neuropathic pain

    NARCIS (Netherlands)

    Poublon, A.R.; Walbeehm, E.T.; Duraku, L.S.; Eilers, P.H.; Kerver, A.L.; Kleinrensink, G.J.; Coert, J.H.

    2015-01-01

    The superficial branch of the radial nerve (SBRN) is known for developing neuropathic pain syndromes after trauma. These pain syndromes can be hard to treat due to the involvement of other nerves in the forearm. When a nerve is cut, the Schwann cells, and also other cells in the distal segment of

  6. The anatomical relationship of the superficial radial nerve and the lateral antebrachial cutaneous nerve : A possible factor in persistent neuropathic pain

    NARCIS (Netherlands)

    Poublon, A. R.; Walbeehm, E. T.; Duraku, L. S.; Eilers, P. H C; Kerver, A. L A; Kleinrensink, G. J.; Coert, J. H.

    The superficial branch of the radial nerve (SBRN) is known for developing neuropathic pain syndromes after trauma. These pain syndromes can be hard to treat due to the involvement of other nerves in the forearm. When a nerve is cut, the Schwann cells, and also other cells in the distal segment of

  7. Epidural spinal cord stimulation for neuropathic pain: a neurosurgical multicentric Italian data collection and analysis.

    Science.gov (United States)

    Colombo, Elena Virginia; Mandelli, Carlo; Mortini, Pietro; Messina, Giuseppe; De Marco, Nicola; Donati, Roberto; Irace, Claudio; Landi, Andrea; Lavano, Angelo; Mearini, Massimo; Podetta, Stefano; Servello, Domenico; Zekaj, Edvin; Valtulina, Carlo; Dones, Ivano

    2015-04-01

    Spinal cord stimulation (SCS) is a technique used worldwide to treat several types of chronic neuropathic pain refractory to any conservative treatment. The aim of this data collection is to enforce evidence of SCS effectiveness on neuropathic chronic pain reported in the literature and to speculate on the usefulness of the trial period in determining the long-term efficacy. Moreover, the very low percentage of undesired side effects and complications reported in our case series suggests that all implants should be performed by similarly well-trained and experienced professionals. A multicentric data collection on a common database from 11 Italian neurosurgical departments started 3 years ago. Two different types of electrodes (paddle or percutaneous leads) were used. Of 122 patients, 73 % (N = 89) were submitted to a trial period, while the remaining patients underwent the immediate permanent implant (N = 33). Statistical comparisons of continuous variables between groups were performed. Most of the patients (80 %) had predominant pain to their lower limbs, while only 17 % of patients had prevalent axial pain. Significant reduction in pain, as measured by variation in visual analogue scale (VAS) score, was observed at least 1 year after implantation in 63.8 % of the cases, 59.5 % of patients who underwent a test trial and 71.4 % of patients who underwent permanent implant at once. No statistical differences were found between the lower-limb pain group and the axial pain group. No relevant differences in long-term outcomes were observed in previously tested patients compared with patients implanted at once. Through this analysis we hope to recruit new centres, to give more scientific value to our results.

  8. A comparison of coping strategies in patients with fibromyalgia, chronic neuropathic pain, and pain-free controls

    DEFF Research Database (Denmark)

    Baastrup, Sidsel; Schultz, Rikke; Brødsgaard, Inger

    2016-01-01

    different groups of chronic pain patients and a group of healthy controls. Thirty neuropathic pain (NP) patients, 28 fibromyalgia (FM) patients, and 26 pain-free healthy controls completed the Coping Strategy Questionnaire (CSQ-48/27) and rated their daily pain. The results showed that FM and NP patients...

  9. Spinal astrocytic activation contributes to mechanical allodynia in a rat chemotherapy-induced neuropathic pain model.

    Directory of Open Access Journals (Sweden)

    Xi-Tuan Ji

    Full Text Available Chemotherapy-induced neuropathic pain (CNP is the major dose-limiting factor in cancer chemotherapy. However, the neural mechanisms underlying CNP remain enigmatic. Accumulating evidence implicates the involvement of spinal glia in some neuropathic pain models. In this study, using a vincristine-evoked CNP rat model with obvious mechanical allodynia, we found that spinal astrocyte rather than microglia was dramatically activated. The mechanical allodynia was dose-dependently attenuated by intrathecal administratration of L-α-aminoadipate (astrocytic specific inhibitor; whereas minocycline (microglial specific inhibitor had no such effect, indicating that spinal astrocytic activation contributes to allodynia in CNP rat. Furthermore, oxidative stress mediated the development of spinal astrocytic activation, and activated astrocytes dramatically increased interleukin-1β expression which induced N-methyl-D-aspartic acid receptor (NMDAR phosphorylation in spinal neurons to strengthen pain transmission. Taken together, our findings suggest that spinal activated astrocytes may be a crucial component of the pathophysiology of CNP and "Astrocyte-Cytokine-NMDAR-neuron" pathway may be one detailed neural mechanisms underlying CNP. Thus, inhibiting spinal astrocytic activation may represent a novel therapeutic strategy for treating CNP.

  10. Treatment of neuropathic cancer pain with continuous intrathecal administration of S (+)-ketamine

    NARCIS (Netherlands)

    Vranken, J. H.; van der Vegt, M. H.; Kal, J. E.; Kruis, M. R.

    2004-01-01

    The effective treatment of patients suffering from neuropathic cancer pain remains a clinical challenge. When patients experience either insufficient analgesia or problematic side-effects after opioid administration, intrathecal administration of morphine and other medications such as bupivacaine

  11. Combined inhibition of monoacylglycerol lipase and cyclooxygenases synergistically reduces neuropathic pain in mice

    Science.gov (United States)

    Crowe, Molly S; Leishman, Emma; Banks, Matthew L; Gujjar, Ramesh; Mahadevan, Anu; Bradshaw, Heather B; Kinsey, Steven G

    2015-01-01

    Background and Purpose Neuropathic pain is commonly treated with GABA analogues, steroids or non-steroidal anti-inflammatory drugs (NSAIDs). NSAIDs inhibit one or more COX isozymes but chronic COX inhibition paradoxically increases gastrointestinal inflammation and risk of unwanted cardiovascular events. The cannabinoids also have analgesic and anti-inflammatory properties and reduce neuropathic pain in animal models. The present study investigated the analgesic effects of inhibiting both monoacylglycerol lipase (MAGL) and COX enzymes, using low doses of both inhibitors. Experimental Approach Mice subjected to chronic constriction injury (CCI) were tested for mechanical and cold allodynia after administration of the MAGL inhibitor, JZL184, or the non-selective COX inhibitor diclofenac. Then, both drugs were co-administered at fixed dose proportions of 1:3, 1:1 and 3:1, based on their ED50 values. PGs, endocannabinoids and related lipids were quantified in lumbar spinal cord. Key Results Combining low doses of JZL184 and diclofenac synergistically attenuated mechanical allodynia and additively reduced cold allodynia. The cannabinoid CB1 receptor antagonist, rimonabant, but not the CB2 receptor antagonist, SR144528, blocked the analgesic effects of the JZL184 and diclofenac combination on mechanical allodynia, implying that CB1 receptors were primarily responsible for the anti-allodynia. Diclofenac alone and with JZL184 significantly reduced PGE2 and PGF2α in lumbar spinal cord tissue, whereas JZL184 alone caused significant increases in the endocannabinoid metabolite, N-arachidonoyl glycine. Conclusions and Implications Combining COX and MAGL inhibition is a promising therapeutic approach for reducing neuropathic pain with minimal side effects. PMID:25393148

  12. Quetiapine reverse paclitaxel-induced neuropathic pain in mice: Role of Alpha2- adrenergic receptors

    Directory of Open Access Journals (Sweden)

    Alireza Abed

    2017-11-01

    Full Text Available Objective(s: Paclitaxel-induced peripheral neuropathy is a common adverse effect of cancer chemo -therapy. This neuropathy has a profound impact on quality of life and patient’s survival. Preventing and treating paclitaxel-induced peripheral neuropathy is a major concern. First- and second-generation antipsychotics have shown analgesic effects both in humans and animals. Quetiapine is a novel atypical antipsychotic with low propensity to induce extrapyramidal or hyperprolactinemia side effects. The present study was designed to investigate the effects of quetiapine on the development and expression of neuropathic pain induced by paclitaxel in mice and the role of α2-adrenoceptors on its antinociception. Materials and Methods: Paclitaxel (2 mg/kg IP was injected for five consecutive days which resulted in thermal hyperalgesia and mechanical and cold allodynia. Results: Early administration of quetiapine from the 1st day until the 5th day (5, 10, and 15 mg/kg PO did not affect thermal, mechanical, and cold stimuli and could not prevent the development of neuropathic pain. In contrast, when quetiapine (10 and 15 mg/kg PO administration was started on the 6th day after the first paclitaxel injections, once the model had been established, and given daily until the 10th day, heat hyperalgesia and mechanical and cold allodynia were significantly attenuated. Also, the effect of quetiapine on heat hyperalgesia was reversed by pretreatment with yohimbine, as an alpha-2 adrenergic receptor antagonist. Conclusion: These results indicate that quetiapine, when administered after nerve injury can reverse the expression of neuropathic pain. Also, we conclude that α2-adrenoceptors participate in the antinociceptive effects of quetiapine.

  13. Virtual reality-augmented neurorehabilitation improves motor function and reduces neuropathic pain in patients with incomplete spinal cord injury.

    Science.gov (United States)

    Villiger, Michael; Bohli, Dominik; Kiper, Daniel; Pyk, Pawel; Spillmann, Jeremy; Meilick, Bruno; Curt, Armin; Hepp-Reymond, Marie-Claude; Hotz-Boendermaker, Sabina; Eng, Kynan

    2013-10-01

    Neurorehabilitation interventions to improve lower limb function and neuropathic pain have had limited success in people with chronic, incomplete spinal cord injury (iSCI). We hypothesized that intense virtual reality (VR)-augmented training of observed and executed leg movements would improve limb function and neuropathic pain. Patients used a VR system with a first-person view of virtual lower limbs, controlled via movement sensors fitted to the patient's own shoes. Four tasks were used to deliver intensive training of individual muscles (tibialis anterior, quadriceps, leg ad-/abductors). The tasks engaged motivation through feedback of task success. Fourteen chronic iSCI patients were treated over 4 weeks in 16 to 20 sessions of 45 minutes. Outcome measures were 10 Meter Walking Test, Berg Balance Scale, Lower Extremity Motor Score, Spinal Cord Independence Measure, Locomotion and Neuropathic Pain Scale (NPS), obtained at the start and at 4 to 6 weeks before intervention. In addition to positive changes reported by the patients (Patients' Global Impression of Change), measures of walking capacity, balance, and strength revealed improvements in lower limb function. Intensity and unpleasantness of neuropathic pain in half of the affected participants were reduced on the NPS test. Overall findings remained stable 12 to 16 weeks after termination of the training. In a pretest/posttest, uncontrolled design, VR-augmented training was associated with improvements in motor function and neuropathic pain in persons with chronic iSCI, several of which reached the level of a minimal clinically important change. A controlled trial is needed to compare this intervention to active training alone or in combination.

  14. Functional brain imaging: what has it brought to our understanding of neuropathic pain? A special focus on allodynic pain mechanisms.

    Science.gov (United States)

    Peyron, Roland

    2016-02-01

    Brain responses to nociception are well identified. The same is not true for allodynic pain, a strong painful sensation in response to touch or innocuous cold stimuli that may be experienced by patients with neuropathic pain. Brain (or spinal cord) reorganization that may explain this paradoxical perception still remains largely unknown. Allodynic pain is associated with abnormally increased activity in SII and in the anterior insular cortex, contralateral and/or ipsilateral to allodynia. Because a bilateral increase in activity has been repeatedly reported in these areas in nociceptive conditions, the observed activation during allodynia can explain that a physiologically nonpainful stimulus could be perceived by the damaged nervous system as a painful one. Both secondary somatosensory and insular cortices receive input from the thalamus, which is a major relay of sensory and spinothalamic pathways, the involvement of which is known to be crucial for the development of neuropathic pain. Both thalamic function and structure have been reported to be abnormal or impaired in neuropathic pain conditions including in the basal state, possibly explaining the spontaneous component of neuropathic pain. A further indication as to how the brain can create neuropathic pain response in SII and insular cortices stems from examples of diseases, including single-case reports in whom a focal brain lesion leads to central pain disappearance. Additional studies are required to certify the contribution of these areas to the disease processes, to disentangle abnormalities respectively related to pain and to deafferentation, and, in the future, to guide targeting of stimulation studies.

  15. Spinal NF-κB and chemokine ligand 5 expression during spinal glial cell activation in a neuropathic pain model.

    Directory of Open Access Journals (Sweden)

    Qin Yin

    Full Text Available BACKGROUND: The NF-κB pathway and chemokine (C-C motif ligand 5 (CCL5 are involved in pain modulation; however, the precise mechanisms of their interactions in chronic neuropathic pain have yet to be established. METHODS: The present study examined the roles of spinal NF-κB and CCL5 in a neuropathic pain model after chronic constriction injury (CCI surgery. CCI-induced pain facilitation was evaluated using the Plantar and von Frey tests. The changes in NF-κB and CCL5 expression were analyzed by immunohistochemistry and Western blot analyses. RESULTS: Spinal NF-κB and CCL5 expression increased after CCI surgery. Repeated intrathecal infusions of pyrrolidine dithiocarbamate (PDTC, a NF-κB inhibitor decreased CCL5 expression, inhibited the activation of microglia and astrocytes, and attenuated CCI-induced allodynia and hyperalgesia. Intrathecal injection of a CCL5-neutralizing antibody attenuated CCI-induced pain facilitation and also suppressed spinal glial cell activation after CCI surgery. However, the CCL5-neutralizing antibody did not affect NF-κB expression. Furthermore, selective glial inhibitors, minocycline and fluorocitrate, attenuated the hyperalgesia induced by intrathecal CCL5. CONCLUSIONS: The inhibition of spinal CCL5 expression may provide a new method to prevent and treat nerve injury-induced neuropathic pain.

  16. Frequency, character, intensity and impact of neuropathic pain in a cohort of spinal cord injury patients

    International Nuclear Information System (INIS)

    Ullah, H.; Akhtar, N.; Matee, S.; Butt, A.W.

    2015-01-01

    The purpose of this study was to determine frequency, character, approximate location and intensity of neuropathic pain in spinal cord injury and its impact on the quality of life. Study Design: A cross-sectional survey Place and Duration of Study: Armed Forces Institute of Rehabilitation Medicine (AFIRM), Rawalpindi from Feb 2009 to Feb 2010. Material and Methods: Through non-probability convenience sampling 87 patients of both genders diagnosed with spinal cord injury based on American Spinal Injury Association criteria and admitted within a year of injury were included. Those in spinal shock, having poor cognition, inability to communicate, concurrent brain injury and history of chronic pain before injury were excluded. The history, localization and characteristics of the pain and interference with life activities were recorded. Neuropathic pain of patients was evaluated with Leeds Assessment of Neuropathic Symptoms and Signs Pain Scale. Visual analogue scale was used to measure the severity of pain. Results: Out of 87 patients (mean age 36.9 years) seventy four were male and 13 were female. Seventy patients (80%) were AIS-A, 6 (7%) were AIS-B and 11 (13%) were AIS-C. Neuropathic pain was present in 57.5% (n=50). Most of the patients localized their pain below the neurological level of injury (78%) and rated pain intensity as moderate pain (54%). Majority (48%) described the pain as burning followed by electric shock like (42%), stabbing (8%) and pricking (2%). 48% patients reported that their quality of life was affected due to pain. 52% required two analgesics of different groups to relieve pain followed by 40% requiring three analgesics and 8% requiring one analgesic. Conclusion: Neuropathic pain is prevalent in people with spinal cord injury and adversely affects life quality. Neuropathic pain is primarily described as a burning sensation of moderate intensity mostly referred to below the neurological level of injury. (author)

  17. Use of high performance technologies in the treatment of chronic neuropathic pain

    Directory of Open Access Journals (Sweden)

    Streltov Ion

    2018-03-01

    Full Text Available Spinal cord neurostimulation is a minimally invasive treatment method for chronic neuropathic pain that is refractory to treatment, and is part of top technology in field. Relatively recent introduction of this method in the Neurosurgery Clinic “Prof. Dr. N. Oblu” of Iasi has aligned the clinic’s therapeutic arsenal to world standards. This has made it possible to treat in Romania a category of patients who would be treated abroad until now. Our clinic has entered the “National Program for diagnostic and treatment using high performance equipment” - Subprogram of treatment of neuropathic pain by implant of a spinal cord neurostimulator and is currently the only one in Romania where this treatment can be done. This represents a new step in the transformation process of the Clinical Hospital Emergency “Prof. Dr. N. Oblu” Iasi in a real Center of Excellence in the field Neurosurgery. The team dealing with the implant consists of 3 neurosurgeons, a neurologist, pa sychologist and an anesthetist, trained in a specialized foreign center.

  18. Neuropathic pain. Redefinition and a grading system for clinical and research purposes

    DEFF Research Database (Denmark)

    Treede, R.-D.; Jensen, Troels Staehelin; Campbell, J.N.

    2008-01-01

    potentially tissue-damaging stimuli. Pain may also arise by activity generated within the nervous system without adequate stimulation of its peripheral sensory endings. For this type of pain, the International Association for the Study of Pain introduced the term neuropathic pain, defined as "pai...... evidence from a neurologic examination. This grading system is proposed for clinical and research purposes....... initiated or caused by a primary lesion or dysfunction in the nervous system." While this definition has been useful in distinguishing some characteristics of neuropathic and nociceptive types of pain, it lacks defined boundaries. Since the sensitivity of the nociceptive system is modulated by its adequate...... activation (e.g., by central sensitization), it has been difficult to distinguish neuropathic dysfunction from physiologic neuroplasticity. We present a more precise definition developed by a group of experts from the neurologic and pain community: pain arising as a direct consequence of a lesion or disease...

  19. HIV Distal Neuropathic Pain Is Associated with Smaller Ventral Posterior Cingulate Cortex.

    Science.gov (United States)

    Keltner, John R; Connolly, Colm G; Vaida, Florin; Jenkinson, Mark; Fennema-Notestine, Christine; Archibald, Sarah; Akkari, Cherine; Schlein, Alexandra; Lee, Jisu; Wang, Dongzhe; Kim, Sung; Li, Han; Rennels, Austin; Miller, David J; Kesidis, George; Franklin, Donald R; Sanders, Chelsea; Corkran, Stephanie; Grant, Igor; Brown, Gregory G; Atkinson, J Hampton; Ellis, Ronald J

    2017-03-01

    . Despite modern antiretroviral therapy, HIV-associated neuropathy is one of the most prevalent, disabling and treatment-resistant complications of HIV disease. The presence and intensity of distal neuropathic pain is not fully explained by the degree of peripheral nerve damage. A better understanding of brain structure in HIV distal neuropathic pain may help explain why some patients with HIV neuropathy report pain while the majority does not. Previously, we reported that more intense distal neuropathic pain was associated with smaller total cerebral cortical gray matter volumes. The objective of this study was to determine which parts of the cortex are smaller. . HIV positive individuals with and without distal neuropathic pain enrolled in the multisite (N = 233) CNS HIV Antiretroviral Treatment Effects (CHARTER) study underwent structural brain magnetic resonance imaging. Voxel-based morphometry was used to investigate regional brain volumes in these structural brain images. . Left ventral posterior cingulate cortex was smaller for HIV positive individuals with versus without distal neuropathic pain (peak P  = 0.017; peak t = 5.15; MNI coordinates x = -6, y = -54, z = 20). Regional brain volumes within cortical gray matter structures typically associated with pain processing were also smaller for HIV positive individuals having higher intensity ratings of distal neuropathic pain. . The posterior cingulate is thought to be involved in inhibiting the perception of painful stimuli. Mechanistically a smaller posterior cingulate cortex structure may be related to reduced anti-nociception contributing to increased distal neuropathic pain. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  20. Biopsychosocial characteristics of patients with neuropathic pain following spinal cord trauma injury. Case reports

    OpenAIRE

    Silva,Viviana Gonçalves; Jesus,Cristine Alves Costa de

    2015-01-01

    ABSTRACTBACKGROUND AND OBJECTIVES:Spinal cord injury is a change in spinal canal structures and may induce motor, sensory, autonomic and psychoaffective changes. Trauma injury is the most prevalent. Neuropathic pain is more frequent in people with spinal cord injury and may be disabling. Pain development mechanism is poorly known being its management difficult for both patients and health professionals. This study aimed at identifying biopsychosocial characteristics associated to neuropathic ...

  1. Neuropathic ocular pain due to dry eye is associated with multiple comorbid chronic pain syndromes

    Science.gov (United States)

    Galor, Anat; Covington, Derek; Levitt, Alexandra E.; McManus, Katherine T.; Seiden, Benjamin; Felix, Elizabeth R.; Kalangara, Jerry; Feuer, William; Patin, Dennis J.; Martin, Eden R.; Sarantopoulos, Konstantinos D.; Levitt, Roy C.

    2015-01-01

    Recent data demonstrate that dry eye (DE) susceptibility and other chronic pain syndromes (CPS) such as chronic widespread pain, irritable bowel syndrome and pelvic pain, may share common heritable factors. Previously, we showed that DE patients describing more severe symptoms tended to report features of neuropathic ocular pain (NOP). We hypothesize that patients with a greater number of CPS would have a different DE phenotype compared to those with fewer CPS. We recruited a cohort of 154 DE patients from the Miami Veterans Affairs Hospital and defined high and low CPS groups by cluster analysis. In addition to worse non-ocular pain complaints and higher PTSD and depression scores (Ppain assessed via 3 different pain scales (Ppain disorder, and that shared mechanistic factors may underlie vulnerability to some forms of DE and other comorbid CPS. PMID:26606863

  2. Effect of a polyherbal formulation cream on diabetic neuropathic pain among patients with type 2 diabetes – A pilot study

    Science.gov (United States)

    Viswanathan, Vijay; Rajsekar, Seena; Selvaraj, Bamila; Kumpatla, Satyavani

    2016-01-01

    Background & objectives: Painful diabetic neuropathy is a common complication of diabetes and can severely limit patients’ daily functions. The aim of this pilot study was to evaluate the safety and effect of using a polyherbal formulation in reducing the symptoms of diabetic neuropathic pain in comparison with placebo among patients with type 2 diabetes. Methods: A total of 50 (M:F = 33:17) consecutive type 2 diabetes patients with painful diabetic neuropathy were enrolled in this study. All these patients had either two or more symptoms of diabetic neuropathy such as pain, burning and pricking sensations and numbness in their feet. They were randomly assigned to two groups: group 1 (n = 26) patients were treated with polyherbal formulation cream and group 2 (n = 24) patients were administered placebo. The patients were followed up for six months. Changes in the symptoms of painful diabetic neuropathy of each patient were recorded at baseline, third and sixth month using the Diabetic Neuropathic Score. Results: The mean age of the patients, duration of diabetes and glycated haemoglobin (HbA1c) were similar in both groups at baseline. During follow up visits, there was a decrease in the HbA1c levels in the study and control groups. The symptoms of painful diabetic neuropathy were also similar in both groups at baseline. A significant decrease in symptoms of neuropathic pain was observed among the group of patients treated with polyherbal formulation cream (76.9 per cent) compared to the placebo-treated group (12.5 per cent) (P<0.001), at the end of the final follow up. Interpretation & conclusions: In this pilot study polyherbal formulation cream was found to be effective as well as safe to treat painful diabetic neuropathy. However, its long term use needs to be evaluated for any further effectiveness and side effects. PMID:27934800

  3. The topical 5% lidocaine medicated plaster in localized neuropathic pain: a reappraisal of the clinical evidence

    Directory of Open Access Journals (Sweden)

    de León-Casasola OA

    2016-02-01

    Full Text Available Oscar A de León-Casasola,1,2 Victor Mayoral3 1Department of Anesthesiology, Division of Pain Medicine, Roswell Park Cancer Institute, 2University at Buffalo, School of Medicine and Biomedical Sciences. NY, USA; 3Anesthesiology Department, Pain Management Unit, University Hospital of Bellvitge, L'Hospitalet de Llobregat, Spain Abstract: Topical 5% lidocaine medicated plasters represent a well-established first-line option for the treatment of peripheral localized neuropathic pain (LNP. This review provides an updated overview of the clinical evidence (randomized, controlled, and open-label clinical studies, real-life daily clinical practice, and case series. The 5% lidocaine medicated plaster effectively provides pain relief in postherpetic neuralgia, and data from a large open-label controlled study indicate that the 5% lidocaine medicated plaster is as effective as systemic pregabalin in postherpetic neuralgia and painful diabetic polyneuropathy but with an improved tolerability profile. Additionally, improved analgesia and fewer side effects were experienced by patients treated synchronously with the 5% lidocaine medicated plaster, further demonstrating the value of multimodal analgesia in LNP. The 5% lidocaine medicated plaster provides continued benefit after long-term (≤7 years use and is also effective in various other LNP conditions. Minor application-site reactions are the most common adverse events associated with the 5% lidocaine medicated plaster; there is minimal risk of systemic adverse events and drug–drug interactions. Although further well-controlled studies are warranted, the 5% lidocaine medicated plaster is efficacious and safe in LNP and may have particular clinical benefit in elderly and/or medically compromised patients because of the low incidence of adverse events. Keywords: 5% lidocaine medicated plaster, clinical evidence, localized neuropathic pain, postherpetic neuralgia, review

  4. [Prevalence and characteristics of chronic pain with neuropathic component at Parakou in northern Benin in 2012].

    Science.gov (United States)

    Adoukonou, T; Gnonlonfoun, D; Kpozehouen, A; Adjien, C; Tchaou, B; Tognon-Tchegnonsi, F; Adechina, H; Covi, R; Houinato, D

    2014-11-01

    The burden of chronic and neuropathic pain is high making it an important public health problem. The epidemiology is not well known in the general population in sub-Saharan Africa. We aimed to determine the prevalence of chronic pain with a neuropathic component at Tititou in Parakou in northeastern Benin. A cross-sectional study was conducted from 1st April to 31 May 2012 and included 2314 people in a door-to-door survey. Chronic pain was defined as pain occurring for more than three months. Neuropathic pain was assessed with the DN4 score. A neurological exam was performed by a young physician for all people with chronic pain. During the interview, sociodemographic data, past medical history, weight and height were recorded. Multivariate logistic regression was performed to analyze the main associated factors. Among the 2314 people included in this survey, 49.7% were male. The mean age was 32.3 ± 13.1 years. Nine hundred seven reported pain occurring for more than 3 months. The prevalence of chronic pain was 39.2% (CI95%: 29.3-34.7). It was more frequent in females, older people, among diabetics, people with a history of any surgery, stroke, brain trauma, and alcoholism. The prevalence of chronic pain with a neuropathic component was 6.3% (CI95%: 5.0-7.9). The main associated factors were age, matrimonial status, professional occupation, body mass index, diabetes, history of zoster, history of any surgery, brain trauma. People with neuropathic pain often reported pain with burning (87.6%), prickling (82.8%), numbness (66.9%), tingling (63.4%), and lightning pain (48.3%). The main locations were the lower limbs and low back pain. This study suggested the high frequency of chronic neuropathic pain in the general population in Parakou compared with rates reported in western countries. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  5. MiR-155 modulates the progression of neuropathic pain through targeting SGK3.

    Science.gov (United States)

    Liu, Shaoxing; Zhu, Bo; Sun, Yan; Xie, Xianfeng

    2015-01-01

    This study aimed to illustrate the potential effects of miR-155 in neuropathic pain and its potential mechanism. Spragure-Dawley (SD) rats were used for neuropathic pain model of bilateral chronic constriction injury (bCCI) construction. Effects of miR-155 expression on pain threshold of mechanical stimuli (MWT), paw withdrawal threshold latency (PMTL) and cold threshold were analyzed. Target for miR-155 was analyzed using bioinformatics methods. Moreover, effects of miR-155 target gene expression on pain thresholds were also assessed. Compared with the controls and sham group, miR-155 was overexpressed in neuropathic pain rats (P<0.05), but miR-155 slicing could significantly decreased the pain thresholds (P<0.05). Serum and glucocorticoid regulated protein kinase 3 (SGK3) was predicted as the target gene for miR-155, and miR-155 expression was negatively correlated to SGK3 expression. Furthermore, SGK3 overexpression could significantly decreased the pain thresholds which was the same as miR-155 (P<0.05). Moreover, miR-155 slicing and SGK3 overexpression could significantly decrease the painthreshold. The data presented in this study suggested that miR-155 slicing could excellently alleviate neuropathic pain in rats through targeting SGK3 expression. miR-155 may be a potential therapeutic target for neuropathic pain treatment.

  6. Neural markers of neuropathic pain associated with maladaptive plasticity in spinal cord injury.

    Science.gov (United States)

    Pascoal-Faria, Paula; Yalcin, Nilufer; Fregni, Felipe

    2015-04-01

    Given the potential use of neural markers for the development of novel treatments in spinal cord pain, we aimed to characterize the most effective neural markers of neuropathic pain following spinal cord injury (SCI). A systematic PubMed review was conducted, compiling studies that were published prior to April, 2014 that examined neural markers associated with neuropathic pain after SCI using electrophysiological and neuroimaging techniques. We identified 6 studies: Four using electroencephalogram (EEG); 1 using magnetic resonance imaging (MRI) and FDG-PET (positron emission tomography); and 1 using MR spectroscopy. The EEG recordings suggested a reduction in alpha EEG peak frequency activity in the frontal regions of SCI patients with neuropathic pain. The MRI scans showed volume loss, primarily in the gray matter of the left dorsolateral prefrontal cortex, and by FDG-PET, hypometabolism in the medial prefrontal cortex was observed in SCI patients with neuropathic pain compared with healthy subjects. In the MR spectroscopy findings, the presence of pain was associated with changes in the prefrontal cortex and anterior cingulate cortex. When analyzed together, the results of these studies seem to point out to a common marker of pain in SCI characterized by decreased cortical activity in frontal areas and possibly increased subcortical activity. These results may contribute to planning further mechanistic studies as to better understand the mechanisms by which neuropathic pain is modulated in patients with SCI as well as clinical studies investigating best responders of treatment. © 2014 World Institute of Pain.

  7. Neuropathic pain screening questionnaires have limited measurement properties. A systematic review.

    Science.gov (United States)

    Mathieson, Stephanie; Maher, Christopher G; Terwee, Caroline B; Folly de Campos, Tarcisio; Lin, Chung-Wei Christine

    2015-08-01

    The Douleur Neuropathique 4 (DN4), ID Pain, Leeds Assessment of Neuropathic Symptoms and Signs (LANSS), PainDETECT, and Neuropathic Pain Questionnaire have been recommended as screening questionnaires for neuropathic pain. This systematic review aimed to evaluate the measurement properties (eg, criterion validity and reliability) of these questionnaires. Online database searches were conducted and two independent reviewers screened studies and extracted data. Methodological quality of included studies and the measurement properties were assessed against established criteria. A modified Grading of Recommendations Assessment, Development and Evaluation approach was used to summarize the level of evidence. Thirty-seven studies were included. Most studies recruited participants from pain clinics. The original version of the DN4 (French) and Neuropathic Pain Questionnaire (English) had the most number of satisfactory measurement properties. The ID Pain (English) demonstrated satisfactory hypothesis testing and reliability, but all other properties tested were unsatisfactory. The LANSS (English) was unsatisfactory for all properties, except specificity. The PainDETECT (English) demonstrated satisfactory hypothesis testing and criterion validity. In general, the cross-cultural adaptations had less evidence than the original versions. Overall, the DN4 and Neuropathic Pain Questionnaire were most suitable for clinical use. These screening questionnaires should not replace a thorough clinical assessment. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

  8. Nerve Regenerative Effects of GABA-B Ligands in a Model of Neuropathic Pain

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    Valerio Magnaghi

    2014-01-01

    Full Text Available Neuropathic pain arises as a direct consequence of a lesion or disease affecting the peripheral somatosensory system. It may be associated with allodynia and increased pain sensitivity. Few studies correlated neuropathic pain with nerve morphology and myelin proteins expression. Our aim was to test if neuropathic pain is related to nerve degeneration, speculating whether the modulation of peripheral GABA-B receptors may promote nerve regeneration and decrease neuropathic pain. We used the partial sciatic ligation- (PSL- induced neuropathic model. The biochemical, morphological, and behavioural outcomes of sciatic nerve were analysed following GABA-B ligands treatments. Simultaneous 7-days coadministration of baclofen (10 mg/kg and CGP56433 (3 mg/kg alters tactile hypersensitivity. Concomitantly, specific changes of peripheral nerve morphology, nerve structure, and myelin proteins (P0 and PMP22 expression were observed. Nerve macrophage recruitment decreased and step coordination was improved. The PSL-induced changes in nociception correlate with altered nerve morphology and myelin protein expression. Peripheral synergic effects, via GABA-B receptor activation, promote nerve regeneration and likely ameliorate neuropathic pain.

  9. The Edible Brown Seaweed Ecklonia cava Reduces Hypersensitivity in Postoperative and Neuropathic Pain Models in Rats

    Directory of Open Access Journals (Sweden)

    Jae Goo Kim

    2014-06-01

    Full Text Available The current study was designed to investigate whether edible brown seaweed Ecklonia cava extracts exhibits analgesic effects in plantar incision and spared nerve injury (SNI rats. To evaluate pain-related behavior, we performed the mechanical withdrawal threshold (MWT and thermal hypersensitivity tests measured by von Frey filaments and a hot/cold plate analgesia meter. Pain-related behavior was also determined through analysis of ultrasonic vocalization. The results of experiments showed MWT values of the group that was treated with E. cava extracts by 300 mg/kg significantly increased; on the contrary, number of ultrasonic distress vocalization of the treated group was reduced at 6 h and 24 h after plantar incision operation (62.8%, p < 0.05. Moreover, E. cava 300 mg/kg treated group increased the paw withdrawal latency in hot-and cold-plate tests in the plantar incision rats. After 15 days of continuous treatment with E. cava extracts at 300 mg/kg, the treated group showed significantly alleviated SNI-induced hypersensitivity response by MWT compared with the control group. In conclusion, these results suggest that E. cava extracts have potential analgesic effects in the case of postoperative pain and neuropathic pain in rats.

  10. Exploring acute-to-chronic neuropathic pain in rats after contusion spinal cord injury.

    Science.gov (United States)

    Gaudet, Andrew D; Ayala, Monica T; Schleicher, Wolfgang E; Smith, Elana J; Bateman, Emily M; Maier, Steven F; Watkins, Linda R

    2017-09-01

    Spinal cord injury (SCI) causes chronic pain in 65% of individuals. Unfortunately, current pain management is inadequate for many SCI patients. Rodent models could help identify how SCI pain develops, explore new treatment strategies, and reveal whether acute post-SCI morphine worsens chronic pain. However, few studies explore or compare SCI-elicited neuropathic pain in rats. Here, we sought to determine how different clinically relevant contusion SCIs in male and female rats affect neuropathic pain, and whether acute morphine worsens later chronic SCI pain. First, female rats received sham surgery, or 150kDyn or 200kDyn midline T9 contusion SCI. These rats displayed modest mechanical allodynia and long-lasting thermal hyperalgesia. Next, a 150kDyn (1s dwell) midline contusion SCI was performed in male and female rats. Interestingly, males, but not females showed SCI-elicited mechanical allodynia; rats of both sexes had thermal hyperalgesia. In this model, acute morphine treatment had no significant effect on chronic neuropathic pain symptoms. Unilateral SCIs can also elicit neuropathic pain that could be exacerbated by morphine, so male rats received unilateral T13 contusion SCI (100kDyn). These rats exhibited significant, transient mechanical allodynia, but not thermal hyperalgesia. Acute morphine did not exacerbate chronic pain. Our data show that specific rat contusion SCI models cause neuropathic pain. Further, chronic neuropathic pain elicited by these contusion SCIs was not amplified by our course of early post-trauma morphine. Using clinically relevant rat models of SCI could help identify novel pain management strategies. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Minocycline Effects on IL-6 Concentration in Macrophage and Microglial Cells in a Rat Model of Neuropathic Pain.

    Science.gov (United States)

    Moini-Zanjani, Taraneh; Ostad, Seyed-Nasser; Labibi, Farzaneh; Ameli, Haleh; Mosaffa, Nariman; Sabetkasaei, Masoumeh

    2016-11-01

    Evidence indicates that neuropathic pain pathogenesis is not confined to changes in the activity of neuronal systems but involves interactions between neurons, inflammatory immune and immune-like glial cells. Substances released from immune cells during inflammation play an important role in development and maintenance of neuropathic pain. It has been found that minocycline suppresses the development of neuropathic pain. Here, we evaluated the analgesic effect of minocycline in a chronic constriction injury (CCI) model of neuropathic pain in rat and assessed IL-6 concentration from cultured macrophage and microglia cells. Male Wistar rat (n=6, 150-200 g) were divided into three different groups: 1) CCI+vehicle, 2) sham+vehicle, and 3) CCI+drug. Minocycline (10, 20, and 40 mg/kg) was injected one hour before surgery and continued daily to day 14 post ligation. Von Frey filaments and acetone, as pain behavioral tests, were used for mechanical allodynia and cold allodynia, respectively. Experiments were performed on day 0 (before surgery) and days 1, 3, 5, 7, 10, and 14 post -injury. At day 14, rats were killed and monocyte-derived macrophage from right ventricle and microglia from lumbar part of the spinal cord were isolated and cultured in RPMI and Leibovitz's media, respectively. IL-6 concentration was evaluated in cell culture supernatant after 24 h. Minocycline (10, 20, and 40 mg/kg) attenuated pain behavior, and a decrease in IL-6 concentration was observed in immune cells compared to CCI vehicle-treated animals. Minocycline reduced pain behavior and decreased IL-6 concentration in macrophage and microglial cells.

  12. Prevalence of Neuropathic Pain in Radiotherapy Oncology Units

    International Nuclear Information System (INIS)

    Manas, Ana; Monroy, Jose Luis; Ramos, Avelino Alia; Cano, Carmen; Lopez-Gomez, Vanessa; Masramon, Xavier; Perez, Maria

    2011-01-01

    Purpose: Neuropathic pain (NP) in cancer patients severely impacts quality of life. Radiotherapy (RT) may cause NP, and at the same time, cancer patients visit RT units for pain relief. NP prevalence at these sites and current analgesic treatment should be assessed to improve management. Methods and Materials: This epidemiological, prospective, multicenter study was undertaken to assess NP prevalence, according to Douleur Neuropathique 4 questions questtionaire (DN4) test results, and analgesic management in cancer pain patients visiting RT oncologic units. Secondary analyses assessed NP etiology and pain intensity (using the Brief Pain Inventory-Short Form) and impact (using the Hospital Anxiety and Depression Scale (HADS), Medical Outcomes Study [MOS] for Sleep, and the Health Survey Short Form-12). Results: A total of 1,098 patients with any kind of pain were registered. NP prevalence was 31.1% (95% confidence interval, 28.4%--33.9%); 291 NP patients (mean age, 62.2 ±12.5 years and 57.7% men) were eligible for study; 49% of patients were overweight. The most frequent tumors were those of breast and lung, and stage IIIB was the most common cancer stage. The tumors caused 75% of NP cases. Anxiety, sleepiness, and depression were common. At 8 weeks, pain intensity and interference with daily activities decreased significantly for 50.8% of responders. Depression and anxiety (p < 0.0001) scores on the Physical Component Summary and Mental Component Summary measures (p < 0.0001) and all MOS-Sleep subscales, except for snoring, improved significantly. The percentage of satisfied patients increased from 13.8% to 87.4% (p < 0.0001) with the current analgesic treatment, which meant a 1.2- and 6-fold increase (p < 0.0001) in narcotic analgesics and anticonvulsants, respectively, compared to previous treatment. Conclusions: NP is highly prevalent at RT oncology units, with sleepiness, anxiety, and depression as frequent comorbidities. There is a need to improve management

  13. Neuropathic pain in patients with spinal cord injury: report of 213 patients.

    Science.gov (United States)

    Teixeira, Manoel Jacobsen; Paiva, Wellingson Silva; Assis, Maruska Salles; Fonoff, Erich Talamoni; Bor-Seng-Shu, Edson; Cecon, Angelo Daros

    2013-09-01

    Management of neuropathic pain following spinal cord injury (SCI) can be a frustrating experience for patients since it poses a therapeutic challenge. In this article the authors describe the clinical characteristics of a group of patients with pain after spinal cord injury. In this retrospective study, 213 patients with SCI and neuropathic pain were assessed. We analyzed clinical characteristics, treatment options, and pain intensity for these patients. The main cause of SCI was spine trauma, which occurred in 169 patients, followed by tumors and infection. Complete lesions were verified in 144 patients. In our study, patients with traumatic SCI and partial lesions seem to be presented with more intense pain; however, this was not statistically significant. Neuropathic pain is a common complaint in patients with SCI and presents a treatment challenge. Knowledge of the clinical characteristics of this group of patients may help determine the best approach to intervention.

  14. Neuropathic pain in patients with spinal cord injury: report of 213 patients

    Directory of Open Access Journals (Sweden)

    Manoel Jacobsen Teixeira

    2013-09-01

    Full Text Available Objective Management of neuropathic pain following spinal cord injury (SCI can be a frustrating experience for patients since it poses a therapeutic challenge. In this article the authors describe the clinical characteristics of a group of patients with pain after spinal cord injury. Methods In this retrospective study, 213 patients with SCI and neuropathic pain were assessed. We analyzed clinical characteristics, treatment options, and pain intensity for these patients. Results The main cause of SCI was spine trauma, which occurred in 169 patients, followed by tumors and infection. Complete lesions were verified in 144 patients. In our study, patients with traumatic SCI and partial lesions seem to be presented with more intense pain; however, this was not statistically significant. Conclusions Neuropathic pain is a common complaint in patients with SCI and presents a treatment challenge. Knowledge of the clinical characteristics of this group of patients may help determine the best approach to intervention.

  15. Behavioral testing in rodent models of orofacial neuropathic and inflammatory pain

    Science.gov (United States)

    Krzyzanowska, Agnieszka; Avendaño, Carlos

    2012-01-01

    Orofacial pain conditions are often very debilitating to the patient and difficult to treat. While clinical interest is high, the proportion of studies performed in the orofacial region in laboratory animals is relatively low, compared with other body regions. This is partly due to difficulties in testing freely moving animals and therefore lack of reliable testing methods. Here we present a comprehensive review of the currently used rodent models of inflammatory and neuropathic pain adapted to the orofacial areas, taking into account the difficulties and drawbacks of the existing approaches. We examine the available testing methods and procedures used for assessing the behavioral responses in the face in both mice and rats and provide a summary of some pharmacological agents used in these paradigms to date. The use of these agents in animal models is also compared with outcomes observed in the clinic. PMID:23139912

  16. Prevalence, Causes, and Treatment of Neuropathic Pain in Dutch Nursing Home Residents : A Retrospective Chart Review

    NARCIS (Netherlands)

    van Kollenburg, Esther G. P.; Lavrijsen, Jan C. M.; Verhagen, Stans C.; Zuidema, Sytse U.; Schalkwijk, Annelies; Vissers, Kris C. P.

    Objectives To identify the prevalence and causes of neuropathic pain in Dutch nursing home residents; to establish the prevalence of painful and nonpainful diabetic polyneuropathy in a subsample of individuals with diabetes mellitus and central poststroke pain (CPSP) in a subsample of individuals

  17. Successful spinal cord stimulation for neuropathic below-level spinal cord injury pain following complete paraplegia: a case report.

    Science.gov (United States)

    Reck, Tim A; Landmann, Gunther

    2017-01-01

    Neuropathic pain is common in patients with spinal cord injury (SCI) and often difficult to treat. We report a case where epidural spinal cord stimulation (SCS) below the level of injury has been successfully applied in a patient with a complete spinal cord lesion. A 53-year-old female presented with neuropathic below-level SCI pain of both lower legs and feet due to complete SCI below T5. Time and pain duration since injury was 2 years. Pain intensity was reported on numeric rating scale with an average of 7/10 (0 meaning no pain, 10 meaning the worst imaginable pain), but also with about 8-10 pain attacks during the day with an intensity of 9/10, which lasted between some minutes and half an hour. SCS was applied below the level of injury at-level T11-L1. After a successful 2 weeks testing period the pulse generator has been implanted permanently with a burst-stimulation pattern. The average pain was reduced to a bearable intensity of 4/10, in addition attacks could be reduced both in frequency and in intensity. This effects lasted for at least three months of follow-up. Even in case of complete SCI, SCS might be effective. Mechanisms of pain relief remain unclear. A modulation of suggested residual spinothalamic tract function may play a role. Further investigation has to be carried out to support this theory.

  18. Preventive Effects of Bee Venom Derived Phospholipase A₂ on Oxaliplatin-Induced Neuropathic Pain in Mice.

    Science.gov (United States)

    Li, Dongxing; Kim, Woojin; Shin, Dasom; Jung, Yongjae; Bae, Hyunsu; Kim, Sun Kwang

    2016-01-19

    Oxaliplatin, a chemotherapy drug used to treat colorectal cancer, induces specific sensory neurotoxicity signs that are aggravated by cold and mechanical stimuli. Here we examined the preventive effects of Bee Venom (BV) derived phospholipase A₂ (bvPLA₂) on oxaliplatin-induced neuropathic pain in mice and its immunological mechanism. The cold and mechanical allodynia signs were evaluated by acetone and von Frey hair test on the hind paw, respectively. The most significant allodynia signs were observed at three days after an injection of oxaliplatin (6 mg/kg, i.p.) and then decreased gradually to a normal level on days 7-9. The oxaliplatin injection also induced infiltration of macrophages and upregulated levels of the pro-inflammatory cytokine interleukin (IL)-1β in the lumbar dorsal root ganglia (DRG). Daily treatment with bvPLA₂ (0.2 mg/kg, i.p.) for five consecutive days prior to the oxaliplatin injection markedly inhibited the development of cold and mechanical allodynia, and suppressed infiltration of macrophages and the increase of IL-1β level in the DRG. Such preventive effects of bvPLA₂ were completely blocked by depleting regulatory T cells (Tregs) with CD25 antibody pre-treatments. These results suggest that bvPLA₂ may prevent oxaliplatin-induced neuropathic pain by suppressing immune responses in the DRG by Tregs.

  19. Topical Ketamine 10% for Neuropathic Pain in Spinal Cord Injury Patients: An Open-Label Trial.

    Science.gov (United States)

    Rabi, Joseph; Minori, Joshua; Abad, Hasan; Lee, Ray; Gittler, Michelle

    2016-01-01

    Topical ketamine, an N-methyl-D-aspartate antagonist, has been shown to be effective in certain neuropathic pain syndromes. The objective of this study was to determine the efficacy of topical ketamine in spinal cord injury patients with neuropathic pain. An open label trial enrolled five subjects at an outpatient rehabilitation hospital with traumatic spinal cord injuries who had neuropathic pain at or below the level of injury. Subjects applied topical ketamine 10% three times a day for a two-week duration. Subjects recorded their numerical pain score-ranging from 0 to 10, with 0 representing "no pain, 5 representing "moderate pain," and 10 being described as "worst possible pain"-in a journal at the time of application of topical ketamine and one hour after application. Using a numerical pain scale allows for something as subjective as pain to be given an objective quantification. Subjects also recorded any occurrence of adverse events and level of satisfaction. All five subjects had a decrease in their numerical pain scale by the end of two weeks, ranging from 14% to 63%. The duration ranged from one hour in one subject to the next application in other subjects. There were no adverse effects. Overall, four out of the five subjects stated they were satisfied. Topical ketamine 10% is an effective neuropathic pain medicine in patients with spinal cord injuries; however, further studies need to be done with a placebo and larger sample size. Copyright© by International Journal of Pharmaceutical Compounding, Inc.

  20. Oscillatory neural representations in the sensory thalamus predict neuropathic pain relief by deep brain stimulation.

    Science.gov (United States)

    Huang, Yongzhi; Green, Alexander L; Hyam, Jonathan; Fitzgerald, James; Aziz, Tipu Z; Wang, Shouyan

    2018-01-01

    Understanding the function of sensory thalamic neural activity is essential for developing and improving interventions for neuropathic pain. However, there is a lack of investigation of the relationship between sensory thalamic oscillations and pain relief in patients with neuropathic pain. This study aims to identify the oscillatory neural characteristics correlated with pain relief induced by deep brain stimulation (DBS), and develop a quantitative model to predict pain relief by integrating characteristic measures of the neural oscillations. Measures of sensory thalamic local field potentials (LFPs) in thirteen patients with neuropathic pain were screened in three dimensional feature space according to the rhythm, balancing, and coupling neural behaviours, and correlated with pain relief. An integrated approach based on principal component analysis (PCA) and multiple regression analysis is proposed to integrate the multiple measures and provide a predictive model. This study reveals distinct thalamic rhythms of theta, alpha, high beta and high gamma oscillations correlating with pain relief. The balancing and coupling measures between these neural oscillations were also significantly correlated with pain relief. The study enriches the series research on the function of thalamic neural oscillations in neuropathic pain and relief, and provides a quantitative approach for predicting pain relief by DBS using thalamic neural oscillations. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Long non-coding RNA CCAT1 modulates neuropathic pain progression through sponging miR-155

    OpenAIRE

    Dou, Lidong; Lin, Hongqi; Wang, Kaiwei; Zhu, Guosong; Zou, Xuli; Chang, Enqiang; Zhu, Yongfeng

    2017-01-01

    Neuropathic pain is caused by dysfunction or primary injury of the somatosensory nervous system. Long noncoding RNAs (lncRNAs) play important roles in the development of neuropathic pain. However, the effects of lncRNA colon cancer associated transcript-1 (CCAT1) in neuropathic pain have not been reported. The model of bilateral sciatic nerve chronic constriction injuries (bCCI) is regarded as long-lasting mechanical hypersensitivity and cold allodynia, which is the representative symptom in ...

  2. Diabetes-induced microvascular complications at the level of the spinal cord; a contributing factor in diabetic neuropathic pain.

    Science.gov (United States)

    Ved, N; Da Vitoria Lobo, M E; Bestall, S M; L Vidueira, C; Beazley-Long, N; Ballmer-Hofer, K; Hirashima, M; Bates, D O; Donaldson, L F; Hulse, R P

    2018-05-17

    Abnormalities of neurovascular interactions within the central nervous system of diabetic patients is associated with the onset of many neurological disease states. However, to date, the link between the neurovascular network within the spinal cord and regulation of nociception has not been investigated despite neuropathic pain being common in diabetes. We hypothesised that hyperglycaemia-induced endothelial degeneration in the spinal cord, due to suppression of VEGF-A/VEGFR2 signalling, induces diabetic neuropathic pain. Nociceptive pain behaviour was investigated in a chemically induced model of type 1 diabetes (streptozotocin induced, insulin supplemented; either vehicle or VEGF-A 165 b treated) and an inducible endothelial knockdown of VEGFR2 (tamoxifen induced). Diabetic animals developed mechanical allodynia and heat hyperalgesia. This was associated with a reduction in the number of blood vessels and reduction in Evans blue extravasation in the lumbar spinal cord of diabetic animals versus age-matched controls. Endothelial markers occludin, CD31 and VE-cadherin were downregulated in the spinal cord of the diabetic group versus controls, as well as a concurrent reduction of VEGF-A 165 b expression. In diabetic animals, VEGF-A 165 b treatment (biweekly intraperitoneal, 20 ng g -1 ) restored normal Evans blue extravasation and prevented vascular degeneration, diabetes-induced central neuron activation and neuropathic pain. Inducible knockdown of VEGFR2 (tamoxifen treated Tie2CreER T2 -vegfr2 flfl mice) led to a reduction in blood vessel network volume in the lumbar spinal cord and development of heat hyperalgesia. These findings indicate that hyperglycaemia leads to a reduction in the VEGF-A/VEGFR2 signalling cascade resulting in endothelial dysfunction in the spinal cord, which could be an undiscovered contributing factor to diabetic neuropathic pain. This article is protected by copyright. All rights reserved. This article is protected by copyright. All

  3. Lipoxin A4 inhibits microglial activation and reduces neuroinflammation and neuropathic pain after spinal cord hemisection.

    Science.gov (United States)

    Martini, Alessandra Cadete; Berta, Temugin; Forner, Stefânia; Chen, Gang; Bento, Allisson Freire; Ji, Ru-Rong; Rae, Giles Alexander

    2016-04-08

    Spinal cord injury (SCI) is a severe neurological disorder with many disabling consequences, including persistent neuropathic pain, which develops in about 40 % of SCI patients and is induced and sustained by excessive and uncontrolled spinal neuroinflammation. Here, we have evaluated the effects of lipoxin A4 (LXA4), a member of a unique class of endogenous lipid mediators with both anti-inflammatory and analgesic properties, on spinal neuroinflammation and chronic pain in an experimental model of SCI. Spinal hemisection at T10 was carried out in adult male CD1 mice and Wistar rats. To test if LXA4 can reduce neuroinflammation and neuropathic pain, each animal received two intrathecal injections of LXA4 (300 pmol) or vehicle at 4 and 24 h after SCI. Sensitivity to mechanical stimulation of the hind paws was evaluated using von Frey monofilaments, and neuroinflammation was tested by measuring the mRNA and/or protein expression levels of glial markers and cytokines in the spinal cord samples after SCI. Also, microglia cultures prepared from murine cortical tissue were used to assess the direct effects of LXA4 on microglial activation and release of pro-inflammatory TNF-α. LXA4 treatment caused significant reductions in the intensity of mechanical pain hypersensitivity and spinal expression levels of microglial markers and pro-inflammatory cytokines induced by SCI, when compared to rodents receiving control vehicle injections. Notably, the increased expressions of the microglial marker IBA-1 and of the pro-inflammatory cytokine TNF-α were the most affected by the LXA4 treatment. Furthermore, cortical microglial cultures expressed ALX/FPR2 receptors for LXA4 and displayed potentially anti-inflammatory responses upon challenge with LXA4. Collectively, our results suggest that LXA4 can effectively modulate microglial activation and TNF-α release through ALX/FPR2 receptors, ultimately reducing neuropathic pain in rodents after spinal cord hemisection. The dual anti

  4. Pharmacological evaluation of tacrolimus (FK-506 on ischemia reperfusion induced vasculatic neuropathic pain in rats

    Directory of Open Access Journals (Sweden)

    Sood Shailja

    2010-06-01

    Full Text Available Abstract Background Ischemia reperfusion (I/R is common in various pathological conditions like diabetic complication, rheumatic arthritis, necrotizing vascular occlusive disease and trauma. Methods We have evaluated the effect of tacrolimus (1, 2 and 3 mg/kg, p.o. for 10 consecutive days on femoral arterial ischemic reperfusion (I/R induced neuropathic pain in rats. Behavioral parameters (i.e. hot plate, radiant heat, acetone drop, tail heat hyperalgesia, tail flick and tail cold allodynia tests were assessed at different time intervals (i.e. 0, 1, 4, 7, 10, 13 and 16th day and biochemical analysis in serum and tissue samples were also performed along with histopathological studies. Results Behavioral pain assessment revealed increase in the paw and tail withdrawal threshold in tacrolimus treated groups against hyperalgesic and allodynic stimuli as compared to the sham control group. We observed a decrease in the serum nitrate and thiobarbituric acid reactive substance (TBARS levels along with reduction in tissue myeloperoxidase (MPO and total calcium levels, whereas, rise in tissue reduced glutathione levels in tacrolimus treated groups. However, significant results were obtained in medium and high dose treated group as compared to sham control group. Histopathological study had revealed the increase in the neuronal edema and axonal degeneration in the I/R group whereas, tacrolimus ameliorate these effects. Conclusion Our results indicate the anti-oxidative, anti-inflammatory and calcium modulatory actions of tacrolimus. Therefore, it can be used as a therapeutic agent for the treatment of vascular inflammatory related neuropathic pain.

  5. Neuropathic pain characteristics in patients from Curitiba (Brazil) with spinal cord injury.

    Science.gov (United States)

    Vall, Janaína; Costa, Carlos Mauricio de Castro; Santos, Terezinha de Jesus Teixeira; Costa, Samuel Bovy de Castro

    2011-02-01

    This was a descriptive cross-sectional study on patients with spinal cord injuries living in Curitiba, Paraná, Brazil. The aim was to evaluate the pain characteristics among such patients seen at referral care centers for spinal cord injury patients in Curitiba. A total of 109 adults with spinal cord injury in this city were evaluated regarding the presence of pain, especially neuropathic pain. Neuropathic pain was evaluated using the DN4 questionnaire, a universal instrument that has been translated and validated for Portuguese. A visual analog scale (VAS) was used to evaluate the intensity of pain. The prevalence of pain among these 109 patients was 31.2% (34 patients). The nociceptive pain presented was classified as musculoskeletal pain (nine patients), visceral pain (four patients) and mixed pain (one patient), thus totaling 14 patients (12.8%). Another 20 patients (18.3%) showed symptoms of neuropathic pain and fulfilled the criteria for neuropathic pain with scores greater than 4 out 10 in the DN4 questionnaire. Regarding the characteristics of the patients with neuropathic pain, most of them were male, younger than 40 years of age and paraplegic with incomplete lesions. They had become injured from 1 to more than 5 years earlier. The predominant etiology was gunshot wounds, and the intensity of their pain was high, with VAS scores greater than 5. This study partially corroborates other studies conducted on this subject. Studies of this type are important for understanding the profile of these patients, for the purpose of designing strategies for their rehabilitation, with a focus on the appropriate treatment and management of pain.

  6. Neuropathic pain characteristics in patients from Curitiba (Brazil with spinal cord injury

    Directory of Open Access Journals (Sweden)

    Janaína Vall

    2011-02-01

    Full Text Available This was a descriptive cross-sectional study on patients with spinal cord injuries living in Curitiba, Paraná, Brazil. The aim was to evaluate the pain characteristics among such patients seen at referral care centers for spinal cord injury patients in Curitiba. A total of 109 adults with spinal cord injury in this city were evaluated regarding the presence of pain, especially neuropathic pain. Neuropathic pain was evaluated using the DN4 questionnaire, a universal instrument that has been translated and validated for Portuguese. A visual analog scale (VAS was used to evaluate the intensity of pain. The prevalence of pain among these 109 patients was 31.2% (34 patients. The nociceptive pain presented was classified as musculoskeletal pain (nine patients, visceral pain (four patients and mixed pain (one patient, thus totaling 14 patients (12.8%. Another 20 patients (18.3% showed symptoms of neuropathic pain and fulfilled the criteria for neuropathic pain with scores greater than 4 out 10 in the DN4 questionnaire. Regarding the characteristics of the patients with neuropathic pain, most of them were male, younger than 40 years of age and paraplegic with incomplete lesions. They had become injured from 1 to more than 5 years earlier. The predominant etiology was gunshot wounds, and the intensity of their pain was high, with VAS scores greater than 5. This study partially corroborates other studies conducted on this subject. Studies of this type are important for understanding the profile of these patients, for the purpose of designing strategies for their rehabilitation, with a focus on the appropriate treatment and management of pain.

  7. Therapeutic implications of toll-like receptors in peripheral neuropathic pain.

    Science.gov (United States)

    Thakur, Krishan K; Saini, Jyoti; Mahajan, Kanika; Singh, Dhyanendra; Jayswal, Dinkar P; Mishra, Srishti; Bishayee, Anupam; Sethi, Gautam; Kunnumakkara, Ajaikumar B

    2017-01-01

    Neuropathic pain is a state of chronic pain arising after peripheral or central nerve injury. These injuries can be mediated through the activation of various cells (astrocytes, microglia and Schwann cells), as well as the dissolution of distal axons. Recent studies have suggested that after nerve injury, Toll-like receptors (TLRs) involved in Wallerian degeneration and generation of neuropathic pain. Furthermore, these TLRs are responsible for the stimulation of astrocytes and microglia that can cause induction of the proinflammatory mediators and cytokines in the spinal cord, thereby leading to the generation and maintenance of neuropathic pain. Indeed considering the prevalence of neuropathic pain and suffering of the affected patients, insights into the diverse mechanism(s) of activation of TLR signaling cascades may open novel avenues for the management of this chronic condition. Moreover, existing therapies like antidepressants, anticonvulsants, opiates and other analgesic are not sufficiently effective in reducing the pain. In this review, we present substantial evidences highlighting the diverse roles of TLRs and their signaling pathways involved in the progression of neuropathic pain. Furthermore, an elaborate discussion on various existing treatment regimens and future targets involving TLRs has also been included. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Analgesic Effect of Indian Gooseberry (Emblica officinalis Fruit Extracts on Postoperative and Neuropathic Pain in Rats

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    Dong Wook Lim

    2016-11-01

    Full Text Available Indian gooseberry (Emblica officinalis fruit, also known as “Amla” is one of the oldest edible fruits known in India. It has also traditionally been used to treat inflammation, and as an analgesic to treat wounds. However, experimental evidence for the analgesic effects of E. officinalis has been lacking. The present study investigated whether E. officinalis extracts exhibit analgesic effects in the plantar incision (PI and spared nerve injury (SNI pain-model rats. We evaluated the mechanical withdrawal threshold (MWT using von Frey filaments, and pain-related behavior was determined after surgery based on ultrasonic vocalization (USV. The group treated with E. officinalis extracts at 300 mg/kg had significantly increased MWT values at 6 h and 24 h after the PI, and had a significantly reduced number of 22–27-kHz USVs at 6 h and 24 h after PI. Moreover, after 15 days of continuous treatment with E. officinalis extracts, the treated group showed significantly alleviated SNI-induced hypersensitivity and reduced pro-inflammatory cytokine levels. Thus, E. officinalis extracts have potential analgesic effects in both postoperative and neuropathic pain models in vivo.

  9. Minocycline treatment inhibits microglial activation and alters spinal levels of endocannabinoids in a rat model of neuropathic pain

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    Elphick Maurice R

    2009-07-01

    Full Text Available Abstract Activation of spinal microglia contributes to aberrant pain responses associated with neuropathic pain states. Endocannabinoids (ECs are present in the spinal cord, and inhibit nociceptive processing; levels of ECs may be altered by microglia which modulate the turnover of endocannabinoids in vitro. Here, we investigate the effect of minocycline, an inhibitor of activated microglia, on levels of the endocannabinoids anandamide and 2-arachidonoylglycerol (2-AG, and the related compound N-palmitoylethanolamine (PEA, in neuropathic spinal cord. Selective spinal nerve ligation (SNL in rats resulted in mechanical allodynia and the presence of activated microglia in the ipsilateral spinal cord. Chronic daily treatment with minocycline (30 mg/kg, ip for 14 days significantly reduced the development of mechanical allodynia at days 5, 10 and 14 post-SNL surgery, compared to vehicle-treated SNL rats (P P P P P

  10. Pain from Dental Implant Placement, Inflammatory Pulpitis Pain, and Neuropathic Pain Present Different Somatosensory Profiles.

    Science.gov (United States)

    Porporatti, André Luís; Bonjardim, Leonardo Rigoldi; Stuginski-Barbosa, Juliana; Bonfante, Estevam Augusto; Costa, Yuri Martins; Rodrigues Conti, Paulo César

    2017-01-01

    To address the two following questions: (1) What kind of somatosensory abnormalities may be characterized in patients receiving dental implants (IMP), in ongoing inflammatory dental pulpitis (IP) patients, and in neuropathic pain (atypical odontalgia [AO]) patients? and (2) What sort of sensory and neural changes may result from dental implant placement surgery and pulpectomy? A total of 60 subjects were divided into three groups: the IMP (n = 20), IP (n = 20), and AO groups (n = 20). Quantitative sensory testing (QST) was performed preoperatively (baseline) for all three groups and postoperatively at 1 month and 3 months after dental implant placement or pulpectomy (in the IMP group and IP group, respectively). Statistical analyses were completed with one-way and two-way analysis of variance and z score transformations (α = 5%). The main findings of this study indicated that: (1) Elevations in mechanical detection threshold (MDT) and in current perception threshold (CPT) related to C-fiber activation, indicating a loss of function, were found at baseline in IP patients; (2) Somatosensory abnormalities such as allodynia, reduced MDT and mechanical pain threshold (MPT), and impaired pain modulation were found in AO patients; (3) No somatosensory alterations after implant placement were found in the IMP group; and (4) Somatosensory alterations in the form of reduction in the CPT related to C-fiber activation were reported 3 months after pulpectomy in the IP group. This study showed that somatosensory abnormalities were evident in AO and IP patients, and somatosensory alterations were seen in IP patients even 3 months after pulpectomy. However, no somatosensory alterations were seen after implant placement.

  11. The application of neuropathic pain questionnaires in burning mouth syndrome patients.

    Science.gov (United States)

    Heo, Jun-Young; Ok, Soo-Min; Ahn, Yong-Woo; Ko, Myung-Yun; Jeong, Sung-Hee

    2015-01-01

    To evaluate and compare the validity of the PainDETECT, DN4, and abbreviated DN4 (DN4i) neuropathic pain questionnaires for primary burning mouth syndrome (BMS), which is a burning sensation in the oral mucosa in the absence of any identifiable organic etiology. Eighty-one patients (42 with primary BMS and 39 with nociceptive pain) complaining of a burning sensation and pain in their oral mucosa were enrolled in this study. All of the patients completed the neuropathic pain questionnaires. The sensitivity, specificity, positive predictive value, negative predictive value, and the area under the receiver operating characteristic (ROC) curve were estimated. Then the relationship between pain intensity and total neuropathic pain score was investigated. Data were analyzed with the chi-square test and independent t test for subjects' baseline characteristic differences, and with Pearson correlation coefficients for the relationship of variables. The mean area under the ROC curves (AUCs) for PainDETECT, DN4, and DN4i were 0.81, 0.79, and 0.81, respectively. There was no statistically significant difference in the AUCs among the questionnaires. PainDETECT, DN4, and DN4i had a lower sensitivity and specificity for BMS compared to previous validation studies. The total scores for PainDETECT, DN4, and DN4i in the primary BMS group were significantly associated with pain intensity. Although the results of this study suggest that neuropathic pain questionnaires, such as PainDETECT and DN4, are not ideal principal screening tools for BMS patients, a substantial proportion of neuropathic symptoms in primary BMS patients were identified.

  12. Effect of minocycline on lumbar radicular neuropathic pain: a randomized, placebo-controlled, double-blind clinical trial with amitriptyline as a comparator

    NARCIS (Netherlands)

    Vanelderen, P.; Zundert, J. Van; Kozicz, L.T.; Puylaert, M.; Vooght, P. De; Mestrum, R.; Heylen, R.; Roubos, E.W.; Vissers, K.C.P.

    2015-01-01

    BACKGROUND: Less than 50% of patients experience sufficient pain relief with current drug therapy for neuropathic pain. Minocycline shows promising results in rodent models of neuropathic pain but was not studied in humans with regard to the treatment of neuropathic pain. METHODS: In this

  13. Cognitive Impairment in Patients with Chronic Neuropathic or Radicular Pain: An Interaction of Pain and Age

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    Orla Moriarty

    2017-06-01

    Full Text Available A growing body of empirical research has confirmed an association between chronic pain and cognitive dysfunction. The aim of the present study was to determine whether cognitive function is affected in patients with a diagnosis of chronic neuropathic or radicular pain relative to healthy control participants matched by age, gender, and years of education. We also examined the interaction of pain with age in terms of cognitive performance. Some limitations of previous clinical research investigating the effects of chronic pain on cognitive function include differences in the pain and cognitive scale materials used, and the heterogeneity of patient participants, both in terms of their demographics and pathological conditions. To address these potential confounds, we have used a relatively homogenous patient group and included both experimental and statistical controls. We have also specifically investigated the interaction effect of pain and age on cognitive performance. Patients (n = 38 and controls (n = 38 were administered a battery of cognitive tests measuring IQ, spatial and verbal memory, attention, and executive function. Educational level, depressive symptoms, and state anxiety were assessed as were medication usage, caffeine, and nicotine consumption to control for possible confounding effects. Both the level of depressive symptoms and the state anxiety score were higher in chronic pain patients than in matched control participants. Chronic pain patients had a lower estimated IQ than controls, and showed impairments on measures of spatial and verbal memory. Attentional responding was altered in the patient group, possibly indicative of impaired inhibitory control. There were significant interactions between chronic pain condition and age on a number of cognitive outcome variables, such that older patients with chronic pain were more impaired than both age-matched controls and younger patients with chronic pain. Chronic pain did not appear

  14. Face-to-face comparison of the predictive validity of two models of neuropathic pain in the rat: analgesic activity of pregabalin, tramadol and duloxetine.

    Science.gov (United States)

    Le Cudennec, Camille; Castagné, Vincent

    2014-07-15

    We compared the preclinical analgesic activity of three marketed drugs with different pharmacological properties, pregabalin, tramadol and duloxetine, described as effective against neuropathic pain in the clinic. These drugs were tested against evoked pain in two different neuropathic models in the rat, the Bennett (CCI) and the Chung (SNL) models. The selected endpoints were tactile allodynia, tactile hyperalgesia, heat hyperalgesia and cold allodynia. Although all three drugs displayed analgesic activity, the effects observed varied according to the behavioral evaluation. Pregabalin showed clear analgesic effects against cold allodynia and tactile hyperalgesia in both the CCI and Chung models. Tramadol was active against all four endpoints in the Chung model with similar effects in the CCI model, apart from tactile allodynia. Duloxetine inhibited tactile allodynia and heat hyperalgesia in both neuropathic pain models. It also displayed efficacy against tactile hyperalgesia in the CCI model and against cold allodynia in the Chung model. These data confirm that the CCI and the Chung models of neuropathic pain do not detect the activity of analgesics with the same sensitivity. Furthermore, the mode of stimulation (tactile or thermal) and the type of endpoint (allodynia or hyperalgesia) can further influence the observed efficacy of gold standards as well as novel compounds developed for treating neuropathic pain symptoms. Copyright © 2014. Published by Elsevier B.V.

  15. The effect of Normast (PEA) in neuropathic pain in spinal cord injury

    DEFF Research Database (Denmark)

    Andresen, Sven Robert; Bing, Jette; Hansen, Rikke Bod Middelhede

    2015-01-01

    Introduction: Neuropathic pain and spasticity after spinal cord injury represent significant problems. Palmitoylethanolamide (PEA) is a fatty acid that is produced in many cells in the body, and it is thought to potentiate the body's own cannabis-like substances (endocannabinoids). PEA is suggested...... to reduce pain and inflammation but randomized controlled trials are lacking. Normast is a medical supplement which contains (PEA) approved for use in Denmark. The primary aim is to investigate the effect of Normast (PEA) on neuropathic pain, and secondary to study the effect of Normast on spasticity...

  16. Transient receptor potential channel polymorphisms are associated with the somatosensory function in neuropathic pain patients.

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    Andreas Binder

    Full Text Available Transient receptor potential channels are important mediators of thermal and mechanical stimuli and play an important role in neuropathic pain. The contribution of hereditary variants in the genes of transient receptor potential channels to neuropathic pain is unknown. We investigated the frequency of transient receptor potential ankyrin 1, transient receptor potential melastin 8 and transient receptor potential vanilloid 1 single nucleotide polymorphisms and their impact on somatosensory abnormalities in neuropathic pain patients. Within the German Research Network on Neuropathic Pain (Deutscher Forscbungsverbund Neuropathischer Schmerz 371 neuropathic pain patients were phenotypically characterized using standardized quantitative sensory testing. Pyrosequencing was employed to determine a total of eleven single nucleotide polymorphisms in transient receptor potential channel genes of the neuropathic pain patients and a cohort of 253 German healthy volunteers. Associations of quantitative sensory testing parameters and single nucleotide polymorphisms between and within groups and subgroups, based on sensory phenotypes, were analyzed. Single nucleotide polymorphisms frequencies did not differ between both the cohorts. However, in neuropathic pain patients transient receptor potential ankyrin 1 710G>A (rs920829, E179K was associated with the presence of paradoxical heat sensation (p = 0.03, and transient receptor potential vanilloid 1 1911A>G (rs8065080, I585V with cold hypoalgesia (p = 0.0035. Two main subgroups characterized by preserved (1 and impaired (2 sensory function were identified. In subgroup 1 transient receptor potential vanilloid 1 1911A>G led to significantly less heat hyperalgesia, pinprick hyperalgesia and mechanical hypaesthesia (p = 0.006, p = 0.005 and pG (rs222747, M315I to cold hypaesthesia (p = 0.002, but there was absence of associations in subgroup 2. In this study we found no evidence that genetic

  17. A long noncoding RNA contributes to neuropathic pain by silencing Kcna2 in primary afferent neurons

    Science.gov (United States)

    Zhao, Xiuli; Tang, Zongxiang; Zhang, Hongkang; Atianjoh, Fidelis E.; Zhao, Jian-Yuan; Liang, Lingli; Wang, Wei; Guan, Xiaowei; Kao, Sheng-Chin; Tiwari, Vinod; Gao, Yong-Jing; Hoffman, Paul N.; Cui, Hengmi; Li, Min; Dong, Xinzhong; Tao, Yuan-Xiang

    2013-01-01

    Neuropathic pain is a refractory disease characterized by maladaptive changes in gene transcription and translation within the sensory pathway. Long noncoding RNAs (lncRNAs) are emerging as new players in gene regulation, but how lncRNAs operate in the development of neuropathic pain is unclear. Here we identify a conserved lncRNA for Kcna2 (named Kcna2 antisense RNA) in first-order sensory neurons of rat dorsal root ganglion (DRG). Peripheral nerve injury increases Kcna2 antisense RNA expression in injured DRG through activation of myeloid zinc finger protein 1, a transcription factor that binds to Kcna2 antisense RNA gene promoter. Mimicking this increase downregulates Kcna2, reduces total Kv current, increases excitability in DRG neurons, and produces neuropathic pain symptoms. Blocking this increase reverses nerve injury-induced downregulation of DRG Kcna2 and attenuates development and maintenance of neuropathic pain. These findings suggest native Kcna2 antisense RNA as a new therapeutic target for the treatment of neuropathic pain. PMID:23792947

  18. Blocking proteinase-activated receptor 2 alleviated neuropathic pain evoked by spinal cord injury.

    Science.gov (United States)

    Wei, H; Wei, Y; Tian, F; Niu, T; Yi, G

    2016-01-01

    Spinal cord injury (SCI) is an extremely serious type of physical trauma observed in clinics. Especially, neuropathic pain resulting from SCI has a lasting and significant impact on most aspects of daily life. Thus, a better understanding of the molecular pathways responsible for the cause of neuropathic pain observed in SCI is important to develop effectively therapeutic agents and treatment strategies. Proteinase-activated receptors (PARs) are a family member of G-protein-coupled receptors and are activated by a proteolytic mechanism. One of its subtypes PAR2 has been reported to be engaged in mechanical and thermal hyperalgesia. Thus, in this study we specifically examined the underlying mechanisms responsible for SCI evoked-neuropathic pain in a rat model. Overall, we demonstrated that SCI increases PAR2 and its downstream pathways TRPV1 and TRPA1 expression in the superficial dorsal horn of the spinal cord. Also, we showed that blocking spinal PAR2 by intrathecal injection of FSLLRY-NH2 significantly inhibits neuropathic pain responses induced by mechanical and thermal stimulation whereas FSLLRY-NH2 decreases the protein expression of TRPV1 and TRPA1 as well as the levels of substance P and calcitonin gene-related peptide. Results of this study have important implications, i.e. targeting one or more of these signaling molecules involved in activation of PAR2 and TRPV1/TRPA1 evoked by SCI may present new opportunities for treatment and management of neuropathic pain often observed in patients with SCI.

  19. Inefficacy of high-dose transdermal fentanyl in a patient with neuropathic pain, a case report.

    NARCIS (Netherlands)

    Bleeker, C.P.; Bremer, R.; Dongelmans, D.A.; Dongen, R.T.M. van; Crul, B.J.P.

    2001-01-01

    Pain partially responsive to opioids can lead to rapid escalating dosages due to tolerance development. In this report the case of a 58-year-old female with neuropathic pain using increasing transdermal (TTS) fentanyl dosages to a maximum dose of 3400 microg/h resulting in fentanyl plasma levels of

  20. Use of Lidocaine Patches for Neuropathic Pain in a Comprehensive Cancer Centre

    Directory of Open Access Journals (Sweden)

    Julia Ann Fleming

    2009-01-01

    Full Text Available BACKGROUND: There are few reports of the use of the lidocaine 5% patch (L5%P for neuropathic pain (NP in the cancer patient. Within a comprehensive cancer centre, L5%P has been prescribed by the Pain and Palliative Care Service (Peter McCallum Cancer Centre, East Melbourne, Victoria, Australia for selected patients with NP since 2001.

  1. Effect of Patient Education on Reducing Medication in Spinal Cord Injury Patients With Neuropathic Pain.

    Science.gov (United States)

    Shin, Ji Cheol; Kim, Na Young; Chang, Shin Hye; Lee, Jae Joong; Park, Han Kyul

    2017-08-01

    To determine whether providing education about the disease pathophysiology and drug mechanisms and side effects, would be effective for reducing the use of pain medication while appropriately managing neurogenic pain in spinal cord injury (SCI) patients. In this prospective study, 109 patients with an SCI and neuropathic pain, participated in an educational pain management program. This comprehensive program was specifically created, for patients with an SCI and neuropathic pain. It consisted of 6 sessions, including educational training, over a 6-week period. Of 109 patients, 79 (72.5%) initially took more than two types of pain medication, and this decreased to 36 (33.0%) after the educational pain management program was completed. The mean pain scale score and the number of pain medications decreased, compared to the baseline values. Compared to the non-response group, the response group had a shorter duration of pain onset (p=0.004), and a higher initial number of different medications (ppain management program, can be a valuable complement to the treatment of spinal cord injured patients with neuropathic pain. Early intervention is important, to prevent patients from developing chronic SCI-related pain.

  2. Alternative treatment strategies for neuropathic pain: Role of Indian medicinal plants and compounds of plant origin-A review.

    Science.gov (United States)

    Singh, Hasandeep; Bhushan, Sakshi; Arora, Rohit; Singh Buttar, Harpal; Arora, Saroj; Singh, Balbir

    2017-08-01

    Neuropathic pain is a complex, chronic pain state accompanied by tissue injury and nerve damage. This important health issue constitutes a challenge for the modern medicine worldwide. The management of neuropathic pain remains a major clinical challenge, pertaining to an inadequate understanding of pathophysiological mechanisms of neuropathic pain. Various classes of drugs have been reported effective for the management of neuropathic pain viz. opiates, tricyclic antidepressants, and antiepileptic agents. However, association of adverse effects with these drugs hinders their confident prescription in people with neuropathic pain. Recently, various medicinal plants have been reported effective for the management of neuropathic pain. So, it may be prudent to look beyond synthetic drugs pertaining to their unprecedented pharmacotherapeutic effects with lesser adverse effects. The extensive literature review has been carried out from databases such as Science direct, Scifinder, Wiley online library, PubMed, Research gate, Google scholar and Chemical Abstracts. The list of Traditional Indian Medicinal plants (TIMPs) and isolated compounds have been compiled which have been reported effective as an alternative therapy for the management of neuropathic pain. This helps the researchers to discover some novel therapeutic agents against neuropathic pain. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  3. Revised definition of neuropathic pain and its grading system: an open case series illustrating its use in clinical practice.

    Science.gov (United States)

    Geber, Christian; Baumgärtner, Ulf; Schwab, Rainer; Müller, Harald; Stoeter, Peter; Dieterich, Marianne; Sommer, Clemens; Birklein, Frank; Treede, Rolf-Detlef

    2009-10-01

    The definition of neuropathic pain has recently been revised by an expert committee of the Neuropathic Pain Special Interest Group of the International Association for the Study of Pain (NeuPSIG) as "pain arising as direct consequence of a lesion or disease affecting the somatosensory system," and a grading system of "definite," "probable," and "possible" neuropathic pain has been introduced. This open case series of 5 outpatients (3 men, 2 women; mean age 48 +/- 12 years) demonstrates how the grading system can be applied, in combination with appropriate confirmatory testing, to diagnosis neuropathic conditions in clinical practice. The proposed grading system includes a dynamic algorithm that enhances the physician's ability to determine with a greater level of certainty whether a pain condition is neuropathic. Its clinical use should be further validated in prospective studies.

  4. Neuropathic ocular pain: an important yet underevaluated feature of dry eye

    Science.gov (United States)

    Galor, A; Levitt, R C; Felix, E R; Martin, E R; Sarantopoulos, C D

    2015-01-01

    Dry eye has gained recognition as a public health problem given its prevalence, morbidity, and cost implications. Dry eye can have a variety of symptoms including blurred vision, irritation, and ocular pain. Within dry eye-associated ocular pain, some patients report transient pain whereas others complain of chronic pain. In this review, we will summarize the evidence that chronicity is more likely to occur in patients with dysfunction in their ocular sensory apparatus (ie, neuropathic ocular pain). Clinical evidence of dysfunction includes the presence of spontaneous dysesthesias, allodynia, hyperalgesia, and corneal nerve morphologic and functional abnormalities. Both peripheral and central sensitizations likely play a role in generating the noted clinical characteristics. We will further discuss how evaluating for neuropathic ocular pain may affect the treatment of dry eye-associated chronic pain. PMID:25376119

  5. Central Sensitization and Neuropathic Features of Ongoing Pain in a Rat Model of Advanced Osteoarthritis.

    Science.gov (United States)

    Havelin, Joshua; Imbert, Ian; Cormier, Jennifer; Allen, Joshua; Porreca, Frank; King, Tamara

    2016-03-01

    Osteoarthritis (OA) pain is most commonly characterized by movement-triggered joint pain. However, in advanced disease, OA pain becomes persistent, ongoing and resistant to treatment with nonsteroidal anti-inflammatory drugs (NSAIDs). The mechanisms underlying ongoing pain in advanced OA are poorly understood. We recently showed that intra-articular (i.a.) injection of monosodium iodoacetate (MIA) into the rat knee joint produces concentration-dependent outcomes. Thus, a low dose of i.a. MIA produces NSAID-sensitive weight asymmetry without evidence of ongoing pain and a high i.a. MIA dose produces weight asymmetry and NSAID-resistant ongoing pain. In the present study, palpation of the ipsilateral hind limb of rats treated 14 days previously with high, but not low, doses of i.a. MIA produced expression of the early oncogene, FOS, in the spinal dorsal horn. Inactivation of descending pain facilitatory pathways using a microinjection of lidocaine within the rostral ventromedial medulla induced conditioned place preference selectively in rats treated with the high dose of MIA. Conditioned place preference to intra-articular lidocaine was blocked by pretreatment with duloxetine (30 mg/kg, intraperitoneally at -30 minutes). These observations are consistent with the likelihood of a neuropathic component of OA that elicits ongoing, NSAID-resistant pain and central sensitization that is mediated, in part, by descending modulatory mechanisms. This model provides a basis for exploration of underlying mechanisms promoting neuropathic components of OA pain and for the identification of mechanisms that might guide drug discovery for treatment of advanced OA pain without the need for joint replacement. Difficulty in managing advanced OA pain often results in joint replacement therapy in these patients. Improved understanding of mechanisms driving NSAID-resistant ongoing OA pain might facilitate development of alternatives to joint replacement therapy. Our findings suggest

  6. Learning and memory in mice with neuropathic pain: impact of old age and progranulin deficiency

    Directory of Open Access Journals (Sweden)

    Boris eAlbuquerque

    2013-11-01

    Full Text Available Persistent neuropathic pain is a frequent consequence of peripheral nerve injuries, particularly in the elderly. Using the IntelliCage we studied if a sciatic nerve injury obstructed learning and memory in young and aged mice, each in wild type and progranulin deficient mice, which develop premature signs of brain aging and are more susceptible to nerve injury evoked nociceptive hypersensitivity and hence allow to assess a potential mutual aggravation of pain and old age. Both young and aged mice developed long-term nerve injury-evoked hyperalgesia and allodynia but, in both genotypes, only aged mice with neuropathic pain showed high error rates in place avoidance acquisition tasks. Once learnt however, aged mice with neuropathic pain maintained the aversive memory longer, i.e. the extinction was significantly slowed. In addition, nerve injury in progranulin deficient mice impaired the learning of spatial sequences of awarded places, particularly in aged mice, whereas easy place preference learning was not affected by nerve injury or progranulin deficiency. The sequencing task required a discrimination of clockwise and anti-clockwise sequences and spatial flexibility to re-learn a novel sequence. The loss of spatial flexibility did not occur in sham operated mice, i.e. was a consequence of nerve injury and suggests that neuropathic pain accelerates manifestations of old age and progranulin deficiency. Neuropathic pain at old age, irrespective of the genotype, resulted in a long maintenance of aversive memory suggesting a negative alliance and possibly mutual aggravation of chronic neuropathic pain and aversive memory at old age.

  7. Blocking mammalian target of rapamycin (mTOR) improves neuropathic pain evoked by spinal cord injury.

    Science.gov (United States)

    Wang, Xiaoping; Li, Xiaojia; Huang, Bin; Ma, Shuai

    2016-01-01

    Spinal cord injury (SCI) is an extremely serious type of physical trauma observed in clinics. Neuropathic pain resulting from SCI has a lasting and significant impact on most aspects of daily life. Thus, a better understanding of the molecular pathways responsible for the cause of neuropathic pain observed in SCI is important to develop effective therapeutic agents and treatment strategies. Mammalian target of rapamycin (mTOR) is a serine/threonine protein kinase that is well known for its critical roles in regulating protein synthesis and growth. Furthermore, compelling evidence supports the notion that widespread dysregulation of mTOR and its downstream pathways are involved in neuropathic pain. Thus, in this study we specifically examined the underlying mechanisms by which mTOR and its signaling pathways are involved in SCI-evoked neuropathic pain in a rat model. Overall, we demonstrated that SCI increased the protein expression of p-mTOR, and mTORmediated- phosphorylation of 4E-binding protein 4 (4E-BP1) and p70 ribosomal S6 protein kinase 1 (S6K1) in the superficial dorsal horn of the spinal cord. Also, we showed that blocking spinal mTOR by intrathecal injection of rapamycin significantly inhibited pain responses induced by mechanical and thermal stimulation. In addition, blocking spinal phosphatidylinositide 3-kinase (p-PI3K) pathway significantly attenuated activities of p-mTOR pathways as well as mechanical and thermal hyperalgesia in SCI rats. Moreover, blocking mTOR and PI3K decreased the enhanced levels of substance P and calcitonin gene-related peptide (CGRP) in the dorsal horn of SCI rats. We revealed specific signaling pathways leading to SCI-evoked neuropathic pain, including the activation of PI3K, mTOR and its downstream signaling pathways. Targeting one or more of these signaling molecules may present new opportunities for treatment and management of neuropathic pain often observed in patients with SCI.

  8. Pain relief and functional improvement in patients with neuropathic pain associated with spinal cord injury: an exploratory analysis of pregabalin clinical trials.

    Science.gov (United States)

    Sadosky, Alesia; Parsons, Bruce; Emir, Birol; Nieshoff, Edward C

    2016-01-01

    Characterizing relationships between pain relief and function can inform patient management decisions. This analysis explored graphically the relationship between pain relief and functional improvement in patients with neuropathic pain associated with spinal cord injury in two clinical trials of pregabalin. This was a post hoc analysis of two randomized, double-blind, clinical trials in patients who were treated with pregabalin (n=181) or placebo (n=172) for neuropathic pain associated with spinal cord injury. The bivariate relationship between percent pain relief and absolute change in the functional outcomes with placebo and pregabalin was evaluated graphically using scatter plots, and loess curves illustrated the extent of the relationship between pain and function. Linear trend analysis evaluated the statistical significance of these relationships using Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT)-based thresholds of pain reduction (Pain Inventory pain interference with function in one of the studies and the Medical Outcomes Study Sleep Scale (an 11-point Numeric Rating Scale) and the Hospital Anxiety and Depression Scale (HADS) for the pooled studies. Data ellipses showed a shift with pregabalin relative to placebo toward greater improvement with increasing pain relief for all outcome measures except HADS. Loess curves suggested a relationship between increased pain relief and improved function except for HADS, with the clearest relationship observed for sleep. Linear trend analysis showed significant relationships between pain and Medical Outcomes Study Sleep Scale (Ppain and function on the modified Brief Pain Inventory Interference Index and most individual items (Ppain reduction. Pregabalin resulted in shifts from placebo toward greater functional improvement with greater pain relief.

  9. Antinociceptive effects of fisetin against diabetic neuropathic pain in mice: Engagement of antioxidant mechanisms and spinal GABAA receptors.

    Science.gov (United States)

    Zhao, Xin; Li, Xin-Lin; Liu, Xin; Wang, Chuang; Zhou, Dong-Sheng; Ma, Qing; Zhou, Wen-Hua; Hu, Zhen-Yu

    2015-12-01

    Peripheral painful neuropathy is one of the most common complications in diabetes and necessitates improved treatment. Fisetin, a naturally occurring flavonoid, has been reported to exert antidepressant-like effect in previous studies. As antidepressant drugs are employed clinically to treat neuropathic pain, this work aimed to investigate whether fisetin possess beneficial effect on diabetic neuropathic pain and explore the mechanism(s). We subjected mice to diabetes by a single intraperitoneal (i.p.) injection of streptozotocin (200mg/kg), and von Frey test or Hargreaves test was used to assess mechanical allodynia or thermal hyperalgesia, respectively. Chronic treatment of diabetic mice with fisetin not only ameliorated the established symptoms of thermal hyperalgesia and mechanical allodynia, but also arrested the development of neuropathic pain when given at low doses. Although chronic fisetin administration did not impact on the symptom of hyperglycemia in diabetic mice, it reduced exacerbated oxidative stress in tissues of spinal cord, dorsal root ganglion (DRG) and sciatic verve. Furthermore, the analgesic actions of fisetin were abolished by repetitive co-treatment with the reactive oxygen species (ROS) donor tert-butyl hydroperoxide (t-BOOH), but potentiated by the ROS scavenger phenyl-N-tert-butylnitrone (PBN). Finally, acute blockade of spinal GABAA receptors by bicuculline totally counteracted such fisetin analgesia. These findings indicate that chronic fisetin treatment can delay or correct neuropathic hyperalgesia and allodynia in mice with type 1 diabetes. Mechanistically, the present fisetin analgesia may be associated with its antioxidant activity, and spinal GABAA receptors are likely rendered as downstream targets. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Pharmacological correlation between the formalin test and the neuropathic pain behavior in different species with chronic constriction injury.

    NARCIS (Netherlands)

    Vissers, K.C.P.; Geenen, F.; Biermans, R.; Meert, T.F.

    2006-01-01

    Research on mechanisms of drug action, and preclinical screening of molecules with a potential activity on neuropathic pain requires extensive animal work. The chronic constriction injury model is one of the best-characterized models of neuropathic pain behavior in rats, but requires extensive time

  11. Mechanistic Differences in Neuropathic Pain Modalities Revealed by Correlating Behavior with Global Expression Profiling

    Directory of Open Access Journals (Sweden)

    Enrique J. Cobos

    2018-01-01

    Full Text Available Chronic neuropathic pain is a major morbidity of neural injury, yet its mechanisms are incompletely understood. Hypersensitivity to previously non-noxious stimuli (allodynia is a common symptom. Here, we demonstrate that the onset of cold hypersensitivity precedes tactile allodynia in a model of partial nerve injury, and this temporal divergence was associated with major differences in global gene expression in innervating dorsal root ganglia. Transcripts whose expression change correlates with the onset of cold allodynia were nociceptor related, whereas those correlating with tactile hypersensitivity were immune cell centric. Ablation of TrpV1 lineage nociceptors resulted in mice that did not acquire cold allodynia but developed normal tactile hypersensitivity, whereas depletion of macrophages or T cells reduced neuropathic tactile allodynia but not cold hypersensitivity. We conclude that neuropathic pain incorporates reactive processes of sensory neurons and immune cells, each leading to distinct forms of hypersensitivity, potentially allowing drug development targeted to each pain type.

  12. The effect of Normast (PEA) on neuropathic pain in spinal cord injury

    DEFF Research Database (Denmark)

    Andresen, Sven Robert; Bing, Jette; Hansen, Rikke Bod Middelhede

    2015-01-01

    status: Presently, 66 patients (74% male) are included of which 55 have completed the trial. Of those included, 5% have complete tetraplegia, 39% incomplete tetraplegia, 29% complete paraplegia and 27% incomplete paraplegia. Average age at inclusion is 55.3 (±9.5) years and average time since injury is 8......Introduction: Neuropathic pain and spasticity after spinal cord injury (SCI) represent still a significant, unresolved problem causing suffering and re¬duced quality of life in patients with SCI. Treatment of neuropathic pain is a complex and difficult task, and many patients have incom......) on neuropathic pain, and sec¬ondary to study the effect of Normast on spas¬ticity and psychological functioning in patients with spinal cord injury. Population characteristics: Gender, male/female, n 43/15 Age since inclusion, years, mean (SD) 55.3 (9.5) Time since injury, years, mean (SD) 8.8 (8.9) Present...

  13. Bioinformatic Analysis of Potential Biomarkers for Spinal Cord Injured Patients With Intractable Neuropathic Pain.

    Science.gov (United States)

    Wang, Yimin; Ye, Fang; Huang, Chanyan; Xue, Faling; Li, Yingyuan; Gao, Shaowei; Qiu, Zeting; Li, Si; Chen, Qinchang; Zhou, Huaqiang; Song, Yiyan; Huang, Wenqi; Tan, Wulin; Wang, Zhongxing

    2018-03-15

    Neuropathic pain is one of the common complications after spinal cord injury (SCI), affecting patients' life quality. The molecular mechanism for neuropathic pain after SCI is still unclear. We aimed to discover potential genes and MicroRNAs(miRNAs) related to neuropathic pain by bioinformatics method. Microarray data of GSE69901 were obtained from Gene Expression Omnibus (GEO) database. Peripheral blood samples from patients with or without neuropathic pain after spinal cord injury (SCI) were collected. 12 samples with neuropathic pain and 13 samples without pain as control were included in the downloaded microarray. Differentially expressed genes (DEGs) between neuropathic pain group and control group were detected using GEO2R online tool. Functional enrichment analysis of DEGs was performed using DAVID database. Protein-protein interaction (PPI) network was constructed from STRING database. MiRNAs targeting these DEGs were obtained from miRNet database. A merged miRNA-DEG network was constructed and analyzed with Cytoscape software. Total 1134 DEGs were identified between patients with or without neuropathic pain(case and control) and 454 biological processes were enriched. We identified 4 targeted miRNAs, including mir-204-5p, mir-519d-3p, mir-20b-5p, mir-6838-5p, which may be the potential biomarker for SCI patients. Protein modification and regulation biological process of central nervous system may be a risk factor of in SCI patients. Certain genes and miRNAs may be potential biomarkers for the prediction of and potential targets for prevention and treatment of neuropathic pain after SCI.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. http

  14. Dynamic Changes in Nociception and Pain Perception After Spinal Cord Stimulation in Chronic Neuropathic Pain Patients.

    Science.gov (United States)

    Biurrun Manresa, José A; Sörensen, Jan; Andersen, Ole K; Arendt-Nielsen, Lars; Gerdle, Björn

    2015-12-01

    Patients with an implanted spinal cord stimulation (SCS) system for pain management present an opportunity to study dynamic changes in the pain system in a situation where patients are not stimulated (ie, experiencing severe pain) compared with a situation in which patients have just been stimulated (ie, pain free or greatly reduced pain). The aims of this study were (1) to determine if there are differences in nociceptive withdrawal reflex thresholds (NWR-T) and electrical pain thresholds (EP-T) before and after SCS; and (2) to establish if these differences are related to psychological factors associated with chronic pain. Seventeen volunteers with chronic neuropathic pain participated in the experiment. Electrical stimuli were applied to assess the NWR-T and the EP-T. In addition, psychological factors (ie, pain characteristics, depression, anxiety, and disability indexes) were also recorded. The NWR-T and EP-T were assessed with the SCS system off (at least 8 h before the experiment), and then reassessed 1 hour after the SCS system was turned on. Ongoing pain intensity ratings decreased (P=0.018), whereas the NWR-T increased (P=0.028) after the SCS was turned on, whereas no significant difference was found for EP-T (P=0.324). Psychological factors were significant predictors for EP-T but not for NWR-T. The results of this study suggest that pain relief after SCS is partially mediated by a decrease in the excitability of dorsal horn neurons in the spinal cord.

  15. Cortical and white matter alterations in patients with neuropathic pain after spinal cord injury.

    Science.gov (United States)

    Yoon, Eun Jin; Kim, Yu Kyeong; Shin, Hyung Ik; Lee, Youngjo; Kim, Sang Eun

    2013-12-02

    Neuropathic pain is one of the major problems of patients with spinal cord injury (SCI), which remains refractory to treatment despite a variety of therapeutic approach. Multimodal neuroimaging could provide complementary information for brain mechanisms underlying neuropathic pain, which could be based on development of more effective treatment strategies. Ten patients suffering from chronic neuropathic pain after SCI and 10 healthy controls underwent FDG-PET, T1-anatomical MRI and diffusion tensor imaging. We found decreases of both metabolism and the gray matter volume in the left dorsolateral prefrontal cortex in patients compared to healthy controls, as well as hypometabolism in the medial prefrontal cortex and gray matter volume loss in bilateral anterior insulae and subgenual anterior cingulate cortices. These brain regions are generally known to participate in pain modulation by affective and cognitive processes. Decreases of mean diffusivity (MD) in the right internal capsule including, cerebral peduncle, pre-and post-central white matter, and prefrontal white matter as components of the corticospinal and thalamocortical tracts were demonstrated in patients. Further, lower MD value of prefrontal white matter was correlated with decreased metabolism of medial prefrontal cortex in patients. These results indicated that white matter changes imply abnormal pain modulation in patients as well as motor impairment. Our study showed the functional and structural multimodal imaging modality commonly identified the possible abnormalities in the brain regions participating pain modulation in neuropathic pain. Multifaceted imaging studies in neuropathic pain could be useful elucidating precise mechanisms of persistent pain, and providing future directions for treatment. © 2013 Elsevier B.V. All rights reserved.

  16. Pain relief and functional improvement in patients with neuropathic pain associated with spinal cord injury: an exploratory analysis of pregabalin clinical trials

    Directory of Open Access Journals (Sweden)

    Sadosky A

    2016-06-01

    Full Text Available Alesia Sadosky,1 Bruce Parsons,1 Birol Emir,1 Edward C Nieshoff2 1Pfizer Inc., New York, NY, 2Rehabilitation Institute of Michigan, Detroit, MI, USA Background: Characterizing relationships between pain relief and function can inform patient management decisions. This analysis explored graphically the relationship between pain relief and functional improvement in patients with neuropathic pain associated with spinal cord injury in two clinical trials of pregabalin. Methods: This was a post hoc analysis of two randomized, double-blind, clinical trials in patients who were treated with pregabalin (n=181 or placebo (n=172 for neuropathic pain associated with spinal cord injury. The bivariate relationship between percent pain relief and absolute change in the functional outcomes with placebo and pregabalin was evaluated graphically using scatter plots, and loess curves illustrated the extent of the relationship between pain and function. Linear trend analysis evaluated the statistical significance of these relationships using Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT-based thresholds of pain reduction (<15%, 15% <30%, 30% to <50%, and ≥50%. Outcome measures included modified Brief Pain Inventory pain interference with function in one of the studies and the Medical Outcomes Study Sleep Scale (an 11-point Numeric Rating Scale and the Hospital Anxiety and Depression Scale (HADS for the pooled studies. Results: Data ellipses showed a shift with pregabalin relative to placebo toward greater improvement with increasing pain relief for all outcome measures except HADS. Loess curves suggested a relationship between increased pain relief and improved function except for HADS, with the clearest relationship observed for sleep. Linear trend analysis showed significant relationships between pain and Medical Outcomes Study Sleep Scale (P<0.0001 and between pain and function on the modified Brief Pain Inventory

  17. Lack of Analgesic Synergy of the Cholecystokinin Receptor Antagonist Proglumide and Spinal Cord Stimulation for the Treatment of Neuropathic Pain in Rats.

    Science.gov (United States)

    Inoue, Shinsuke; Johanek, Lisa M; Sluka, Kathleen A

    2017-08-01

    Neuropathic pain is difficult to manage and treat. Spinal cord stimulation (SCS) has become an established procedure for treating chronic neuropathic pain that is refractory to pharmacological therapy. In order to achieve better analgesia, a number of studies have evaluated the effectiveness of combining drug therapy with SCS. Cholecystokinin antagonists, such as proglumide, enhance the analgesic efficacy of endogenous opioids in animal models of pain. We previously reported that both systemic and spinal administration of proglumide enhances analgesia produced by both low- and high-frequency transcutaneous electrical nerve stimulation (TENS). Since SCS produces analgesia through endogenous opioids, we hypothesized that the analgesic effect of SCS would be enhanced through co-administration with proglumide in animals with neuropathic pain. Male Sprague-Dawley rats (n = 40) with spared nerve injury were given proglumide (20 mg/kg, i.p.) or saline prior to treatment with SCS (sham, 4 Hz, and 60 Hz). Mechanical withdrawal thresholds of the paw were measured before and after induction of nerve injury, and after SCS. Physical activity levels were measured after SCS. Both proglumide and SCS when given independently significantly increased withdrawal thresholds two weeks after nerve injury. However, there was no additional effect of combining proglumide and SCS on mechanical withdrawal thresholds or activity levels in animals with nerve injury. Proglumide may be a candidate for achieving analgesia for patients with refractory neuropathic pain conditions, but does not enhance analgesia produced by SCS. © 2017 International Neuromodulation Society.

  18. Evaluating Sativex® in Neuropathic Pain Management: A Clinical and Neurophysiological Assessment in Multiple Sclerosis.

    Science.gov (United States)

    Russo, Margherita; Naro, Antonino; Leo, Antonino; Sessa, Edoardo; D'Aleo, Giangaetano; Bramanti, Placido; Calabrò, Rocco Salvatore

    2016-06-01

    The aim of our study was to better investigate the role of Sativex(®) in improving pain in multiple sclerosis (MS) patients by means of either clinical or neurophysiological assessment. Pain is a common symptom of MS, affecting up to 70% of patients. Pain treatment is often unsatisfactory, although emerging drugs (including cannabinoids) are giving encouraging results. Clinical pain assessment in MS is very difficult, and more objective tools are necessary to better quantify this symptom and its potential response to the treatments. We enrolled 20 MS patients (10 with and 10 without neuropathic pain), who underwent a specific clinical (such as visual analog scale) and neurophysiological assessment (by means of laser-evoked potentials and transcranial magnetic stimulation), before and after 4 weeks of Sativex administration. One month of drug administration in MS patients with neuropathic pain successfully reduced pain rating and improved quality of life. Interestingly, such effects were paralleled by an increase of fronto-central γ-band oscillation and of pain-motor integration strength. Our data suggest that Sativex may be effective in improving MS-related neuropathic pain, maybe through its action on specific cortical pathways. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Chemokines in neuron-glial cell interaction and pathogenesis of neuropathic pain.

    Science.gov (United States)

    Zhang, Zhi-Jun; Jiang, Bao-Chun; Gao, Yong-Jing

    2017-09-01

    Neuropathic pain resulting from damage or dysfunction of the nervous system is a highly debilitating chronic pain state and is often resistant to currently available treatments. It has become clear that neuroinflammation, mainly mediated by proinflammatory cytokines and chemokines, plays an important role in the establishment and maintenance of neuropathic pain. Chemokines were originally identified as regulators of peripheral immune cell trafficking and were also expressed in neurons and glial cells in the central nervous system. In recent years, accumulating studies have revealed the expression, distribution and function of chemokines in the spinal cord under chronic pain conditions. In this review, we provide evidence showing that several chemokines are upregulated after peripheral nerve injury and contribute to the pathogenesis of neuropathic pain via different forms of neuron-glia interaction in the spinal cord. First, chemokine CX3CL1 is expressed in primary afferents and spinal neurons and induces microglial activation via its microglial receptor CX3CR1 (neuron-to-microglia signaling). Second, CCL2 and CXCL1 are expressed in spinal astrocytes and act on CCR2 and CXCR2 in spinal neurons to increase excitatory synaptic transmission (astrocyte-to-neuron signaling). Third, we recently identified that CXCL13 is highly upregulated in spinal neurons after spinal nerve ligation and induces spinal astrocyte activation via receptor CXCR5 (neuron-to-astrocyte signaling). Strategies that target chemokine-mediated neuron-glia interactions may lead to novel therapies for the treatment of neuropathic pain.

  20. Aromatherapy Massage for Neuropathic Pain and Quality of Life in Diabetic Patients.

    Science.gov (United States)

    Gok Metin, Zehra; Arikan Donmez, Ayse; Izgu, Nur; Ozdemir, Leyla; Arslan, Ismail Emre

    2017-07-01

    This study aimed to examine the effects of aromatherapy massage on neuropathic pain severity and quality of life (QoL) in patients suffering from painful diabetic neuropathy. This open-label randomized controlled clinical study was conducted in a university hospital endocrine outpatient clinic in Turkey. The study sample consisted of 46 patients, randomly allocated to an intervention group (n = 21) and a control group (n = 25). The intervention group received aromatherapy massage three times per week for a period of 4 weeks. The control group received only routine care. Data were collected from patients using the Douleur Neuropathique questionnaire, the visual analog scale, and the Neuropathic Pain Impact on Quality of Life questionnaire. Neuropathic pain scores significantly decreased in the intervention group compared with the control group in the fourth week of the study. Similarly, QoL scores significantly improved in the intervention group in the fourth week of the study. Aromatherapy massage is a simple and effective nonpharmacological nursing intervention that can be used to manage neuropathic pain and improve QoL in patients with painful neuropathy. Aromatherapy massage is a well-tolerated, feasible, and safe nonpharmacological method that can be readily integrated into clinical settings by nursing staff. The essential oils rosemary, geranium, lavender, eucalyptus, and chamomile can be safely used by nurses in the clinical setting, if applicable. However, training and experience of nurses in aromatherapy massage is critical to achieving positive results. © 2017 Sigma Theta Tau International.

  1. Neuropathic pain in experimental autoimmune neuritis is associated with altered electrophysiological properties of nociceptive DRG neurons.

    Science.gov (United States)

    Taha, Omneya; Opitz, Thoralf; Mueller, Marcus; Pitsch, Julika; Becker, Albert; Evert, Bernd Oliver; Beck, Heinz; Jeub, Monika

    2017-11-01

    Guillain-Barré syndrome (GBS) is an acute, immune-mediated polyradiculoneuropathy characterized by rapidly progressive paresis and sensory disturbances. Moderate to severe and often intractable neuropathic pain is a common symptom of GBS, but its underlying mechanisms are unknown. Pathology of GBS is classically attributed to demyelination of large, myelinated peripheral fibers. However, there is increasing evidence that neuropathic pain in GBS is associated with impaired function of small, unmyelinated, nociceptive fibers. We therefore examined the functional properties of small DRG neurons, the somata of nociceptive fibers, in a rat model of GBS (experimental autoimmune neuritis=EAN). EAN rats developed behavioral signs of neuropathic pain. This was accompanied by a significant shortening of action potentials due to a more rapid repolarization and an increase in repetitive firing in a subgroup of capsaicin-responsive DRG neurons. Na + current measurements revealed a significant increase of the fast TTX-sensitive current and a reduction of the persistent TTX-sensitive current component. These changes of Na + currents may account for the significant decrease in AP duration leading to an overall increase in excitability and are therefore possibly directly linked to pathological pain behavior. Thus, like in other animal models of neuropathic and inflammatory pain, Na + channels seem to be crucially involved in the pathology of GBS and may constitute promising targets for pain modulating pharmaceuticals. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Cervical Spinal Cord and Dorsal Nerve Root Stimulation for Neuropathic Upper Limb Pain.

    Science.gov (United States)

    Levine, Adrian B; Parrent, Andrew G; MacDougall, Keith W

    2017-01-01

    Spinal cord stimulation (SCS) is a well-established treatment for chronic neuropathic pain in the lower limbs. Upper limb pain comprises a significant proportion of neuropathic pain patients, but is often difficult to target specifically and consistently with paresthesias. We hypothesized that the use of dorsal nerve root stimulation (DNRS), as an option along with SCS, would help us better relieve pain in these patients. All 35 patients trialed with spinal stimulation for upper limb pain between July 1, 2011, and October 31, 2013, were included. We performed permanent implantation in 23/35 patients based on a visual analogue scale pain score decrease of ≥50% during trial stimulation. Both the SCS and DNRS groups had significant improvements in average visual analogue scale pain scores at 12 months compared with baseline, and the majority of patients in both groups obtained ≥50% pain relief. The majority of patients in both groups were able to reduce their opioid use, and on average had improvements in Short Form-36 quality of life scores. Complication rates did not differ significantly between the two groups. Treatment with SCS or DNRS provides meaningful long-term relief of chronic neuropathic pain in the upper limbs.

  3. Event-related cortical processing in neuropathic pain under long-term spinal cord stimulation.

    Science.gov (United States)

    Weigel, Ralf; Capelle, H Holger; Flor, Herta; Krauss, Joachim K

    2015-01-01

    Several mechanisms were suggested in the past to explain the beneficial effect of spinal cord stimulation (SCS) in patients suffering from neuropathic pain. Little is known about potential supraspinal mechanisms. In this study cortical signaling of patients with neuropathic pain and successful long-term treatment with SCS was analyzed. Observational study. University hospital, neurosurgical department, outpatient clinic for movement disorders and pain, institute for cognitive and clinical neuroscience. Nine patients with neuropathic pain of a lower extremity with a lasting response to chronic SCS were included. Cortical activity was analyzed using event-related potentials of the electroencephalogram after non-painful and painful stimulation. Each patient was tested under the effect of long-term SCS and 24 hours after cessation of SCS. Cortical areas involved in the peaks of evoked potentials were localized using a source localization method based on a fixed dipole model. Detection threshold and intensity of non-painful stimulation did not differ significantly on both sides. Pain threshold was significantly lower on the neuropathic side under the effect of SCS (P = 0.03). Bilateral pain thresholds were significantly lower (P = 0.03 healthy side, P = 0.003 neuropathic side) in 5 patients with increased pain after cessation of SCS. Under the effect of SCS cortical negativities (N1, N2, N3) and positivities (P1) demonstrated bilaterally comparable amplitudes. After cessation of SCS, decreased threshold for peripheral stimulation resulted in lowered negativities on both sides. The positivity P1 was differentially regulated and was reduced more contralateral to the unaffected side. N2 was localized at the sensory representation of the leg within the homunculus. The main vector of P1 was localized within the cingular cortex (CC) and moved more anteriorly under the effect of SCS. The exact time span that SCS continues to have an effect is not known. However, due to patient

  4. Protective Effect of Ethanol Extracts of Hericium erinaceus on Alloxan-Induced Diabetic Neuropathic Pain in Rats

    Directory of Open Access Journals (Sweden)

    Zhang Yi

    2015-01-01

    Full Text Available We investigated the effects of Hericium erinaceus (HEE on alloxan induced diabetic neuropathic pain in laboratory rats. Alloxan induced diabetic rats were administered orally HEE. After 6 weeks of treatments, treatment with HEE 40 mg/kg in diabetic animals showed significant increase in pain threshold and paw withdrawal threshold and significant decrease in serum glucose and urine glucose. We also observed a significant increase in lactate dehydrogenase (LDH, Lipid peroxidation (LPO, glutathione peroxidase (GPx activity, glutathione reductase (GR activity, catalase (CAT activity, Na+K+ATPase activity, and glutathione S transferase (GST activity along with significant decreased levels of glutathione (GSH content in diabetic rats. The total antioxidant status (TAOS in the HEE-treated groups was significantly lower than that in the alloxan-treated group. HEE can offer pain relief in diabetic neuropathic pain. The improvement in diabetic state after HEE treatment along with the antioxidant activity could be the probable way by which it had alleviated diabetic neuropathy.

  5. Protective Effect of Ethanol Extracts of Hericium erinaceus on Alloxan-Induced Diabetic Neuropathic Pain in Rats

    Science.gov (United States)

    Yi, Zhang; Shao-long, Yang; Ai-hong, Wang; Zhi-chun, Sun; Ya-fen, Zhuo; Ye-ting, Xu; Yu-ling, He

    2015-01-01

    We investigated the effects of Hericium erinaceus (HEE) on alloxan induced diabetic neuropathic pain in laboratory rats. Alloxan induced diabetic rats were administered orally HEE. After 6 weeks of treatments, treatment with HEE 40 mg/kg in diabetic animals showed significant increase in pain threshold and paw withdrawal threshold and significant decrease in serum glucose and urine glucose. We also observed a significant increase in lactate dehydrogenase (LDH), Lipid peroxidation (LPO), glutathione peroxidase (GPx) activity, glutathione reductase (GR) activity, catalase (CAT) activity, Na+K+ATPase activity, and glutathione S transferase (GST) activity along with significant decreased levels of glutathione (GSH) content in diabetic rats. The total antioxidant status (TAOS) in the HEE-treated groups was significantly lower than that in the alloxan-treated group. HEE can offer pain relief in diabetic neuropathic pain. The improvement in diabetic state after HEE treatment along with the antioxidant activity could be the probable way by which it had alleviated diabetic neuropathy. PMID:25960754

  6. Presence of neuropathic pain may explain poor performances on olfactory testing in diabetes mellitus patients.

    Science.gov (United States)

    Brady, Shauna; Lalli, Paul; Midha, Nisha; Chan, Ayechen; Garven, Alexandra; Chan, Cynthia; Toth, Cory

    2013-07-01

    Olfactory dysfunction in neurodegenerative conditions such as Parkinson's syndrome and Alzheimer's disease can hallmark disease onset. We hypothesized that patients with diabetes mellitus, a condition featuring peripheral and central neurodegeneration, would have decreased olfaction abilities. We examined participants with diabetic peripheral neuropathy, participants with diabetes without diabetic peripheral neuropathy, and control participants in blinded fashion using standardized Sniffin' Sticks. Diabetic peripheral neuropathy severity was quantified using the Utah Early Neuropathy Scale. Further subcategorization of diabetic peripheral neuropathy based on presence of neuropathic pain was performed with Douleur Neuropathique 4 Questionnaires. Participants with diabetes had decreased olfactory sensitivity, impaired olfactory discrimination abilities, and reduced odor identification skills when compared with controls. However, loss of olfaction ability was, at least partially, attributed to presence of neuropathic pain on subcategory assessment, although pain severity was not associated with dysfunction. Those participants with diabetes without diabetic peripheral neuropathy and those with diabetic peripheral neuropathy without neuropathic pain had similar olfactory function as controls in general. The presence of neuropathic pain, associated with limited attention and concentration, may explain at least a portion of the olfactory dysfunction witnessed in the diabetic patient population.

  7. Dynamics of circadian thalamocortical flow of information during a peripheral neuropathic pain condition

    Directory of Open Access Journals (Sweden)

    Helder eCardoso-Cruz

    2011-08-01

    Full Text Available It is known that the thalamocortical loop plays a crucial role in the encoding of sensory-discriminative features of painful stimuli. However, only a few studies have addressed the changes in thalamocortical dynamics that may occur after the onset of chronic pain. Our goal was to evaluate how the induction of chronic neuropathic pain affected the flow of information within the thalamocortical loop throughout the brain states of the sleep-wake cycle. To address this issue we recorded local field potentials – LFPs – both before and after the establishment of neuropathic pain in awake freely moving adult rats chronically implanted with arrays of multielectrodes in the lateral thalamus and primary somatosensory cortex. Our results show that the neuropathic injury induced changes in the number of wake and slow-wave-sleep state episodes, and especially in the total number of transitions between brain states. Moreover, partial directed coherence – PDC – analysis revealed that the amount of information flow between cortex and thalamus in neuropathic animals decreased significantly, indicating that the overall thalamic activity had less weight over the cortical activity. However, thalamocortical LFPs displayed higher phase-locking during awake and slow-wave-sleep episodes after the nerve lesion, suggesting faster transmission of relevant information along the thalamocortical loop. The observed changes are in agreement with the hypothesis of thalamic dysfunction after the onset of chronic pain, and may result from diminished inhibitory effect of the primary somatosensory cortex over the lateral thalamus.

  8. Ultramicronized palmitoylethanolamide in spinal cord injury neuropathic pain: A randomized, double-blind, placebo-controlled trial

    DEFF Research Database (Denmark)

    Andresen, Sven R; Bing, Jette; Hansen, Rikke Bod Middelhede

    2016-01-01

    , double-blind, placebo-controlled, parallel multicenter study was performed to investigate the effect of ultramicronized PEA (PEA-um) as add-on therapy on neuropathic pain in individuals with SCI. A pain diary was completed and questionnaires were completed before and after the 12-week treatment...... with either placebo or PEA-um. The primary outcome measure was the change in mean neuropathic pain intensity from the 1-week baseline period to the last week of treatment measured on a numeric rating scale ranging from 0 to 10. The primary efficacy analysis was the intention to treat (baseline observation...... included in the primary analysis. There was no difference in mean pain intensity between PEA-um and placebo treatment (P = 0.46, mean reductions in pain scores 0.4 (-0.1 to 0.9) vs 0.7 (0.2-1.2); difference of means 0.3 (-0.4 to 0.9)). There was also no effect of PEA-um as add-on therapy on spasticity...

  9. Neuropathic pain-like alterations in muscle nociceptor function associated with vibration-induced muscle pain.

    Science.gov (United States)

    Chen, Xiaojie; Green, Paul G; Levine, Jon D

    2010-11-01

    We recently developed a rodent model of the painful muscle disorders induced by occupational exposure to vibration. In the present study we used this model to evaluate the function of sensory neurons innervating the vibration-exposed gastrocnemius muscle. Activity of 74 vibration-exposed and 40 control nociceptors, with mechanical receptive fields in the gastrocnemius muscle, were recorded. In vibration-exposed rats ∼15% of nociceptors demonstrated an intense and long-lasting barrage of action potentials in response to sustained suprathreshold mechanical stimulation (average of 2635 action potentials with frequency of ∼44Hz during a 1min suprathreshold stimulus) much greater than that has been reported to be produced even by potent inflammatory mediators. While these high-firing nociceptors had lower mechanical thresholds than the remaining nociceptors, exposure to vibration had no effect on conduction velocity and did not induce spontaneous activity. Hyperactivity was not observed in any of 19 neurons from vibration-exposed rats pretreated with intrathecal antisense for the IL-6 receptor subunit gp130. Since vibration can injure peripheral nerves and IL-6 has been implicated in painful peripheral neuropathies, we suggest that the dramatic change in sensory neuron function and development of muscles pain, induced by exposure to vibration, reflects a neuropathic muscle pain syndrome. Copyright © 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  10. Spinal cord stimulation for chronic pain of neuropathic or ischaemic origin: systematic review and economic evaluation.

    Science.gov (United States)

    Simpson, E L; Duenas, A; Holmes, M W; Papaioannou, D; Chilcott, J

    2009-03-01

    This report addressed the question 'What is the clinical and cost-effectiveness of spinal cord stimulation (SCS) in the management of chronic neuropathic or ischaemic pain?' Thirteen electronic databases [including MEDLINE (1950-2007), EMBASE (1980-2007) and the Cochrane Library (1991-2007)] were searched from inception; relevant journals were hand-searched; and appropriate websites for specific conditions causing chronic neuropathic/ischaemic pain were browsed. Literature searches were conducted from August 2007 to September 2007. A systematic review of the literature sought clinical and cost-effectiveness data for SCS in adults with chronic neuropathic or ischaemic pain with inadequate response to medical or surgical treatment other than SCS. Economic analyses were performed to model the cost-effectiveness and cost-utility of SCS in patients with neuropathic or ischaemic pain. From approximately 6000 citations identified, 11 randomised controlled trials (RCTs) were included in the clinical effectiveness review: three of neuropathic pain and eight of ischaemic pain. Trials were available for the neuropathic conditions failed back surgery syndrome (FBSS) and complex regional pain syndrome (CRPS) type I, and they suggested that SCS was more effective than conventional medical management (CMM) or reoperation in reducing pain. The ischaemic pain trials had small sample sizes, meaning that most may not have been adequately powered to detect clinically meaningful differences. Trial evidence failed to demonstrate that pain relief in critical limb ischaemia (CLI) was better for SCS than for CMM; however, it suggested that SCS was effective in delaying refractory angina pain onset during exercise at short-term follow-up, although not more so than coronary artery bypass grafting (CABG) for those patients eligible for that surgery. The results for the neuropathic pain model suggested that the cost-effectiveness estimates for SCS in patients with FBSS who had inadequate

  11. Systematic review and comparison of pharmacologic therapies for neuropathic pain associated with spinal cord injury

    Directory of Open Access Journals (Sweden)

    Snedecor SJ

    2013-07-01

    Full Text Available Sonya J Snedecor,1 Lavanya Sudharshan,1 Joseph C Cappelleri,2 Alesia Sadosky,3 Pooja Desai,4 Yash J Jalundhwala,5 Marc Botteman1 1Pharmerit International, Bethesda, MD, USA; 2Global Research and Development, Pfizer, Groton, CT, USA; 3Biostatistics, Pfizer, New York, NY, USA; 4College of Pharmacy, University of Texas at Austin, Austin, TX, USA; 5Pharmacy Administration, University of Illinois at Chicago, Chicago, IL, USA Background: Management of neuropathic pain (NeP associated with spinal cord injury (SCI is difficult. This report presents a systematic literature review and comparison of the efficacy and safety of pharmacologic therapies for treating SCI-associated NeP. Methods: Medline, Embase, Cochrane, and Database of Abstracts of Reviews of Effects were searched through December 2011 for randomized, blinded, and controlled clinical trials of SCI-associated NeP meeting predefined inclusion criteria. Efficacy outcomes of interest were pain reduction on the 11-point numeric rating scale (NRS or 100 mm visual analog scale and proportion of patients achieving ≥30% or ≥50% pain reduction. Discontinuations and adverse events (AEs were also assessed, for which Bayesian meta-analytic indirect comparisons were performed. Results: Of the nine studies included in the analysis, samples were <100 patients, except for one pregabalin study (n = 136. Standard errors for the NRS outcome were often not reported, precluding quantitative comparisons across treatments. Estimated 11-point NRS pain reduction relative to placebo was –1.72 for pregabalin, –1.65 for amitriptyline, –1.0 for duloxetine, –1 (median for levetiracetam, –0.27 for gabapentin, 1 (median for lamotrigine, and 2 for dronabinol. Risk ratios relative to placebo for 30% improvement were 0.71 for levetiracetam and 2.56 for pregabalin, and 0.94 and 2.91, respectively, for 50% improvement. Meta-analytic comparisons showed significantly more AEs with pregabalin and tramadol compared with

  12. Spinal cord stimulation of dorsal columns in a rat model of neuropathic pain: evidence for a segmental spinal mechanism of pain relief.

    Science.gov (United States)

    Smits, H; van Kleef, M; Joosten, E A

    2012-01-01

    Although spinal cord stimulation (SCS) of the dorsal columns is an established method for treating chronic neuropathic pain, patients still suffer from a substantial level of pain. From a clinical perspective it is known that the location of the SCS is of pivotal importance, thereby suggesting a segmental spinal mode of action. However, experimental studies suggest that SCS acts also through the modulation of supraspinal mechanisms, which might suggest that the location is unimportant. Here we investigated the effect of the rostrocaudal location of SCS stimulation and the effectiveness of pain relief in a rat model of chronic neuropathic pain. Adult male rats (n=45) were submitted to a partial ligation of the sciatic nerve. The majority of animals developed tactile hypersensitivity in the nerve lesioned paw. All allodynic rats were submitted to SCS (n=33) for 30 minutes (f=50 Hz; pulse width 0.2 ms). In one group (n=16) the electrodes were located at the level where the injured sciatic nerve afferents enter the spinal cord (T13), and in a second group (n=17) the electrodes were positioned at more rostral levels (T11) as verified by X-ray. A repositioning experiment of electrodes from T12 to T13 was performed in 2 animals. Our data demonstrate that SCS of the dorsal columns at the level where the injured fibers enter the spinal cord dorsal horn result in a much better pain-relieving effect than SCS at more rostral levels. From this we conclude that SCS in treatment of neuropathic pain acts through a segmental spinal site of action. Copyright © 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  13. Neural tissue engineering scaffold with sustained RAPA release relieves neuropathic pain in rats.

    Science.gov (United States)

    Ding, Tan; Zhu, Chao; Kou, Zhen-Zhen; Yin, Jun-Bin; Zhang, Ting; Lu, Ya-Cheng; Wang, Li-Ying; Luo, Zhuo-Jing; Li, Yun-Qing

    2014-09-01

    To investigate the effect of locally slow-released rapamycin (RAPA) from bionic peripheral nerve stent to reduce the incidence of neuropathic pain or mitigate the degree of pain after nerve injury. We constructed a neural tissue engineering scaffold with sustained release of RAPA to repair 20mm defects in rat sciatic nerves. Four presurgical and postsurgical time windows were selected to monitor the changes in the expression of pain-related dorsal root ganglion (DRG) voltage-gated sodium channels 1.3 (Nav1.3), 1.7 (Nav1.7), and 1.8 (Nav1.8) through immunohistochemistry (IHC) and Western Blot, along with the observation of postsurgical pathological pain in rats by pain-related behavior approaches. Relatively small upregulation of DRG sodium channels was observed in the experimental group (RAPA+poly(lactic-co-glycolic acid) (PLGA)+stent) after surgery, along with low degrees of neuropathic pain and anxiety, which were similar to those in the Autologous nerve graft group. Autoimmune inflammatory response plays a leading role in the occurrence of post-traumatic neuropathic pain, and that RAPA significantly inhibits the abnormal upregulation of sodium channels to reduce pain by alleviating inflammatory response. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Executive summary of the Clinical Guidelines of Pharmacotherapy for Neuropathic Pain: second edition by the Japanese Society of Pain Clinicians.

    Science.gov (United States)

    Sumitani, Masahiko; Sakai, Tetsuya; Matsuda, Yoichi; Abe, Hiroaki; Yamaguchi, Shigeki; Hosokawa, Toyoshi; Fukui, Sei

    2018-06-01

    Neuropathic pain has a substantial effect on quality of life (QOL). The Japanese Society of Pain Clinicians (JSPC) has developed clinical guidelines of pharmacotherapy for neuropathic pain. These guidelines offer clarity on recommendations based on both the most recent scientific evidence and expert opinions. Understanding the concept, disease entity, and burden of neuropathic pain, as well as its screening and diagnosis are important steps before starting pharmacotherapy. As well as other guidelines, the guidelines propose several lines of pharmacotherapies in a step-wise manner. To name a few different points, our guidelines propose an extract from inflamed cutaneous tissue of rabbits inoculated with vaccinia virus, which has been found to be effective for post-herpetic neuralgia in Japan, as one of the second-line drugs. When prescribing opioid analgesics, proposed as the third-line drugs, for neuropathic pain, the guidelines recommend physicians continue evaluations on either abuse or addiction. The guidelines do not recommend concomitant use of nonsteroidal anti-inflammatory drugs and acetaminophen because of lack of clinical evidence of their efficacy. If patients do not respond well to pharmacotherapy, which is prescribed in a step-wise manner, other treatment strategies should be considered to improve patients' activities of daily living and QOL.

  15. D-Aspartate Modulates Nociceptive-Specific Neuron Activity and Pain Threshold in Inflammatory and Neuropathic Pain Condition in Mice

    Directory of Open Access Journals (Sweden)

    Serena Boccella

    2015-01-01

    Full Text Available D-Aspartate (D-Asp is a free D-amino acid found in the mammalian brain with a temporal-dependent concentration based on the postnatal expression of its metabolizing enzyme D-aspartate oxidase (DDO. D-Asp acts as an agonist on NMDA receptors (NMDARs. Accordingly, high levels of D-Asp in knockout mice for Ddo gene (Ddo−/− or in mice treated with D-Asp increase NMDAR-dependent processes. We have here evaluated in Ddo−/− mice the effect of high levels of free D-Asp on the long-term plastic changes along the nociceptive pathway occurring in chronic and acute pain condition. We found that Ddo−/− mice show an increased evoked activity of the nociceptive specific (NS neurons of the dorsal horn of the spinal cord (L4–L6 and a significant decrease of mechanical and thermal thresholds, as compared to control mice. Moreover, Ddo gene deletion exacerbated the nocifensive responses in the formalin test and slightly reduced pain thresholds in neuropathic mice up to 7 days after chronic constriction injury. These findings suggest that the NMDAR agonist, D-Asp, may play a role in the regulation of NS neuron electrophysiological activity and behavioral responses in physiological and pathological pain conditions.

  16. Neuropathic pain and its treatment with ARA 290 and ketamine : overlapping pathways

    NARCIS (Netherlands)

    Swartjes, Maarten

    2014-01-01

    Neuropathic pain is a disabling disease with a mechanism consisting of several pathways that ultimately converge in the development and persistence tactile and cold allodynia. Pharmacological treatment is often inadequate and coincides with intolerable side effects. The spared nerve injury animal

  17. Exploring the potential effect of Ocimum sanctum in vincristine-induced neuropathic pain in rats

    Directory of Open Access Journals (Sweden)

    Jaggi Amteshwar

    2010-01-01

    Full Text Available Abstract The present study was designed to investigate the ameliorative potential of Ocimum sanctum and its saponin rich fraction in vincristine-induced peripheral neuropathic pain in rats. Peripheral neuropathy was induced in rats by administration of vincristine sulfate (50 μg/kg i.p. for 10 consecutive days. The mechanical hyperalgesia, cold allodynia, paw heat hyperalgesia and cold tail hyperalgesia were assessed by performing the pinprick, acetone, hot plate and cold tail immersion tests, respectively. Biochemically, the tissue thio-barbituric acid reactive species (TBARS, super-oxide anion content (markers of oxidative stress and total calcium levels were measured. Vincristine administration was associated with the development of mechanical hyperalgesia, cold allodynia, heat and cold hyperalgesia. Furthermore, vincristine administration was also associated with an increase in oxidative stress and calcium levels. However, administration of Ocimum sanctum (100 and 200 mg/kg p.o. and its saponin rich fraction (100 and 200 mg/kg p.o. for 14 days significantly attenuated vincristine-induced neuropathic pain along with decrease in oxidative stress and calcium levels. It may be concluded that Ocimum sanctum has ameliorative potential in attenuating chemotherapy induced-painful neuropathic state, which may be attributed to decrease in oxidative stress and calcium levels. Furthermore, saponin rich fraction of Ocimum sanctum may be responsible for its noted beneficial effect in neuropathic pain in rats.

  18. Neuropathic Pain and Lung Delivery of Nanoparticulate Drugs: An Emerging Novel Therapeutic Strategy.

    Science.gov (United States)

    Islam, Nazrul; Abbas, Muzaffar; Rahman, Shafiqur

    2017-01-01

    Neuropathic pain is a chronic neurological disorder affecting millions of people around the world. The currently available pharmacologic agents for the treatment of neuropathic pain have limited efficacy and are associated with dose related unwanted adverse effects. Due to the limited access of drug molecules across blood-brain barrier, a small percentage of drug that is administered systematically, reaches the central nervous system in active form. These therapeutic agents also require daily treatment regimen that is inconvenient and potentially impact patient compliance. Application of nanoparticulate drugs for enhanced delivery system has been explored extensively in the last decades. Pulmonary delivery of nanomedicines for the management of various diseases has become an emerging treatment strategy that ensures the targeted delivery of drugs both for systemic and local effects with low dose and limited adverse effects. To the best of our knowledge, there are no inhaled drug products available on market for the treatment of neuropathic pain. The advantages of delivering therapeutics into deep lungs include non-invasive drug delivery, higher bioavailability with low dose, lower systemic toxicity, and potentially greater blood-brain barrier penetration. This review discusses and highlights the important issues on the application of emerging nanoparticulate lung delivery of drugs for the effective treatment of neuropathic pain. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  19. α2δ Modulators for management of compression neuropathic pain: A review of three case series

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    Tariq A Tramboo

    2009-01-01

    Conclusion: These results indicate the effectiveness of a2d modulators for management of neuropathic pain secondary to compression radiculopathy. The results also suggest a possible therapeutic superiority of LYRICA over locally available generic brands of pregabalin and gabapentin. These findings need to be further examined in randomized, controlled trials.

  20. Ultramicronized Palmitoylethanolamide (PEA) in spinal cord injury neuropathic pain: a randomized controlled trial

    DEFF Research Database (Denmark)

    Andresen, Sven Robert; Bing, Jette; Hansen, Rikke Bod Middelhede

    2015-01-01

    . Methods  A randomized, double-blind, placebo-controlled parallel multicenter study. Study population of at least 66 patients must complete the 12 week trial.Questionnaires regarding neuropathic pain, spasticity, insomnia, anxiety and depression are completed before and after treatment. A numeric...

  1. Neurophysiological and histopathological evaluation of small fiber pathways as diagnostic characterization of neuropathic pain and autonom dysfunction syndromes

    OpenAIRE

    Devigli, Grazia

    2012-01-01

    This manuscript is made up of two individual not related articles about peripheral neuropathic pain syndrome. The first article reports the effect on pain relief in patients with peripheral neuropathic pain after brachial plexus lesions or distal peripheral nerve injury using an implanted peripheral nerve stimulator applied directly on nerve branch using a peculiar surgical technique. Seven patients with post-traumatic lesion of brachial plexus or peripheral nerve complaining severe intractab...

  2. A preliminary report on stem cell therapy for neuropathic pain in humans

    Directory of Open Access Journals (Sweden)

    Vickers ER

    2014-05-01

    Full Text Available E Russell Vickers,1 Elisabeth Karsten,2 John Flood,3 Richard Lilischkis21Sydney Oral and Maxillofacial Surgery, NSW, Australia; 2Regeneus Ltd, Gordon, NSW, Australia; 3St Vincents Hospital, Sydney, NSW, AustraliaObjective: Mesenchymal stem cells (MSCs have been shown in animal models to attenuate chronic neuropathic pain. This preliminary study investigated if: i injections of autologous MSCs can reduce human neuropathic pain and ii evaluate the safety of the procedure.Methods: Ten subjects with symptoms of neuropathic trigeminal pain underwent liposuction. The lipoaspirate was digested with collagenase and washed with saline three times. Following centrifugation, the stromal vascular fraction was resuspended in saline, and then transferred to syringes for local injections into the pain fields. Outcome measures at 6 months assessed reduction in: i pain intensity measured by standard numerical rating scale from 0–10 and ii daily dosage requirements of antineuropathic pain medication.Results: Subjects were all female (mean age 55.3 years ± standard deviation [SD] 14.67; range 27–80 years with pain symptoms lasting from 4 months to 6 years and 5 months. Lipoaspirate collection ranged from 102–214 g with total cell numbers injected from 33 million to 162 million cells. Cell viability was 62%–91%. There were no systemic or local tissue side effects from the stem cell therapy (n=41 oral and facial injection sites. Clinical pain outcomes showed that at 6 months, 5/9 subjects had reduced both pain intensity scores and use of antineuropathic medication. The mean pain score pre-treatment was 7.5 (SD 1.58 and at 6 months had decreased to 4.3 (SD 3.28, P=0.018, Wilcoxon signed-rank test. Antineuropathic pain medication use showed 5/9 subjects reduced their need for medication (gabapentin, P=0.053, Student's t-test.Conclusion: This preliminary open-labeled study showed autologous administration of stem cells for neuropathic trigeminal pain

  3. Botulinum Toxin Type A—A Modulator of Spinal Neuron–Glia Interactions under Neuropathic Pain Conditions

    Directory of Open Access Journals (Sweden)

    Ewelina Rojewska

    2018-04-01

    Full Text Available Neuropathic pain represents a significant clinical problem because it is a chronic condition often refractory to available therapy. Therefore, there is still a strong need for new analgesics. Botulinum neurotoxin A (BoNT/A is used to treat a variety of clinical diseases associated with pain. Glia are in continuous bi-directional communication with neurons to direct the formation and refinement of synaptic connectivity. This review addresses the effects of BoNT/A on the relationship between glia and neurons under neuropathic pain. The inhibitory action of BoNT/A on synaptic vesicle fusion that blocks the release of miscellaneous pain-related neurotransmitters is known. However, increasing evidence suggests that the analgesic effect of BoNT/A is mediated through neurons and glial cells, especially microglia. In vitro studies provide evidence that BoNT/A exerts its anti-inflammatory effect by diminishing NF-κB, p38 and ERK1/2 phosphorylation in microglia and directly interacts with Toll-like receptor 2 (TLR2. Furthermore, BoNT/A appears to have no more than a slight effect on astroglia. The full activation of TLR2 in astroglia appears to require the presence of functional TLR4 in microglia, emphasizing the significant interaction between those cell types. In this review, we discuss whether and how BoNT/A affects the spinal neuron–glia interaction and reduces the development of neuropathy.

  4. Comparison of central versus peripheral delivery of pregabalin in neuropathic pain states

    Directory of Open Access Journals (Sweden)

    Martinez Jose A

    2012-01-01

    Full Text Available Abstract Background Although pregabalin therapy is beneficial for neuropathic pain (NeP by targeting the CaVα2δ-1 subunit, its site of action is uncertain. Direct targeting of the central nervous system may be beneficial for the avoidance of systemic side effects. Results We used intranasal, intrathecal, and near-nerve chamber forms of delivery of varying concentrations of pregabalin or saline delivered over 14 days in rat models of experimental diabetic peripheral neuropathy and spinal nerve ligation. As well, radiolabelled pregabalin was administered to determine localization with different deliveries. We evaluated tactile allodynia and thermal hyperalgesia at multiple time points, and then analyzed harvested nervous system tissues for molecular and immunohistochemical changes in CaVα2δ-1 protein expression. Both intrathecal and intranasal pregabalin administration at high concentrations relieved NeP behaviors, while near-nerve pregabalin delivery had no effect. NeP was associated with upregulation of CACNA2D1 mRNA and CaVα2δ-1 protein within peripheral nerve, dorsal root ganglia (DRG, and dorsal spinal cord, but not brain. Pregabalin's effect was limited to suppression of CaVα2δ-1 protein (but not CACNA2D1 mRNA expression at the spinal dorsal horn in neuropathic pain states. Dorsal root ligation prevented CaVα2δ-1 protein trafficking anterograde from the dorsal root ganglia to the dorsal horn after neuropathic pain initiation. Conclusions Either intranasal or intrathecal pregabalin relieves neuropathic pain behaviours, perhaps due to pregabalin's effect upon anterograde CaVα2δ-1 protein trafficking from the DRG to the dorsal horn. Intranasal delivery of agents such as pregabalin may be an attractive alternative to systemic therapy for management of neuropathic pain states.

  5. Low doses of dextromethorphan have a beneficial effect in the treatment of neuropathic pain.

    Science.gov (United States)

    Morel, Véronique; Pickering, Gisèle; Etienne, Monique; Dupuis, Amandine; Privat, Anne-Marie; Chalus, Maryse; Eschalier, Alain; Daulhac, Laurence

    2014-12-01

    N-methyl-D-aspartate receptor (NMDAR) antagonists may be given in persistent neuropathic pain, but adverse events especially with ketamine may limit their clinical use. Less central and cognitive adverse events are described with dextromethorphan and memantine. These molecules have been explored in many preclinical and clinical studies, but data are conflicting as regards neuropathic pain alleviation. Dextromethorphan and memantine have been administered to animals after spinal nerve ligation (SNL) to evaluate their antinociceptive/cognitive effects and associated molecular events, including the phosphorylation of several tyrosine (pTyr(1336), pTyr(1472)) residues in the NR2B NMDAR subunit. Spinal nerve ligation and sham animals received dextromethorphan (10 mg/kg, i.p.), memantine (20 mg/kg, i.p.) or saline (1 mL/kg, i.p.). These drugs were administered once symptoms of allodynia and hyperalgesia had developed. Tests were carried out before and after surgery. Tactile allodynia, mechanical hyperalgesia and spatial memory were, respectively, evaluated by von Frey, Randall & Selitto and Y-maze tests and molecular events by Western blot analysis. Spinal nerve-ligated animals displayed nociception and impaired spatial memory. Dextromethorphan, but not memantine, reversed neuropathic pain (NP) symptoms, restored spatial memory integrity and decreased the expression of pTyr(1336)NR2B. Following postoperative administration of dextromethorphan, this study has demonstrated for the first time a concordance between behaviour, cognitive function and molecular events via pTyr(1336)NR2B for neuropathic pain alleviation. Confirmation of these findings in patients would constitute a major step forward in the treatment of neuropathic pain and in the improvement of cognitive function and quality of life. © 2014 Société Française de Pharmacologie et de Thérapeutique.

  6. DRG Voltage-Gated Sodium Channel 1.7 Is Upregulated in Paclitaxel-Induced Neuropathy in Rats and in Humans with Neuropathic Pain.

    Science.gov (United States)

    Li, Yan; North, Robert Y; Rhines, Laurence D; Tatsui, Claudio Esteves; Rao, Ganesh; Edwards, Denaya D; Cassidy, Ryan M; Harrison, Daniel S; Johansson, Caj A; Zhang, Hongmei; Dougherty, Patrick M

    2018-01-31

    Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse effect experienced by cancer patients receiving treatment with paclitaxel. The voltage-gated sodium channel 1.7 (Na v 1.7) plays an important role in multiple preclinical models of neuropathic pain and in inherited human pain phenotypes, and its gene expression is increased in dorsal root ganglia (DRGs) of paclitaxel-treated rats. Hence, the potential of change in the expression and function of Na v 1.7 protein in DRGs from male rats with paclitaxel-related CIPN and from male and female humans with cancer-related neuropathic pain was tested here. Double immunofluorescence in CIPN rats showed that Na v 1.7 was upregulated in small DRG neuron somata, especially those also expressing calcitonin gene-related peptide (CGRP), and in central processes of these cells in the superficial spinal dorsal horn. Whole-cell patch-clamp recordings in rat DRG neurons revealed that paclitaxel induced an enhancement of ProTx II (a selective Na v 1.7 channel blocker)-sensitive sodium currents. Bath-applied ProTx II suppressed spontaneous action potentials in DRG neurons occurring in rats with CIPN, while intrathecal injection of ProTx II significantly attenuated behavioral signs of CIPN. Complementarily, DRG neurons isolated from segments where patients had a history of neuropathic pain also showed electrophysiological and immunofluorescence results indicating an increased expression of Na v 1.7 associated with spontaneous activity. Na v 1.7 was also colocalized in human cells expressing transient receptor potential vanilloid 1 and CGRP. Furthermore, ProTx II decreased firing frequency in human DRGs with spontaneous action potentials. This study suggests that Na v 1.7 may provide a potential new target for the treatment of neuropathic pain, including chemotherapy (paclitaxel)-induced neuropathic pain. SIGNIFICANCE STATEMENT This work demonstrates that the expression and function of the voltage-gated sodium channel Na

  7. Longitudinal Structural and Functional Brain Network Alterations in a Mouse Model of Neuropathic Pain.

    Science.gov (United States)

    Bilbao, Ainhoa; Falfán-Melgoza, Claudia; Leixner, Sarah; Becker, Robert; Singaravelu, Sathish Kumar; Sack, Markus; Sartorius, Alexander; Spanagel, Rainer; Weber-Fahr, Wolfgang

    2018-04-22

    Neuropathic pain affects multiple brain functions, including motivational processing. However, little is known about the structural and functional brain changes involved in the transition from an acute to a chronic pain state. Here we combined behavioral phenotyping of pain thresholds with multimodal neuroimaging to longitudinally monitor changes in brain metabolism, structure and connectivity using the spared nerve injury (SNI) mouse model of chronic neuropathic pain. We investigated stimulus-evoked pain responses prior to SNI surgery, and one and twelve weeks following surgery. A progressive development and potentiation of stimulus-evoked pain responses (cold and mechanical allodynia) were detected during the course of pain chronification. Voxel-based morphometry demonstrated striking decreases in volume following pain induction in all brain sites assessed - an effect that reversed over time. Similarly, all global and local network changes that occurred following pain induction disappeared over time, with two notable exceptions: the nucleus accumbens, which played a more dominant role in the global network in a chronic pain state and the prefrontal cortex and hippocampus, which showed lower connectivity. These changes in connectivity were accompanied by enhanced glutamate levels in the hippocampus, but not in the prefrontal cortex. We suggest that hippocampal hyperexcitability may contribute to alterations in synaptic plasticity within the nucleus accumbens, and to pain chronification. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Characteristics of neuropathic pain and its relationship with quality of life in 72 patients with spinal cord injury.

    Science.gov (United States)

    Nagoshi, N; Kaneko, S; Fujiyoshi, K; Takemitsu, M; Yagi, M; Iizuka, S; Miyake, A; Hasegawa, A; Machida, M; Konomi, T; Machida, M; Asazuma, T; Nakamura, M

    2016-09-01

    A cross-sectional study. Neuropathic pain (NP) after spinal cord injury (SCI) tends to be hard to treat, and its heterogeneous properties make it difficult to identify and characterize. This study was conducted to assess the characteristics of SCI-related NP in detail. A single hospital for SCI rehabilitation. This study included 72 patients who were seen at our hospital in 2012 and 2013 and who had sustained SCI at least 3 months before enrollment. The patients completed the Neuropathic Pain Symptom Inventory (NPSI) and the Short Form (SF)-36 Health Inventory. The NPSI score was analyzed for correlations with clinical presentations of SCI and SF-36 subitems. Paresthesia/dysesthesia was the most common subtype of NP after SCI. With regard to location, below-level superficial NP was significantly more intense than at-level pain. Patients who underwent surgery showed significantly less evoked pain compared with patients with non-surgery. Patients reported significantly more severe pain if >1 year had elapsed after the SCI. Patients with an American Spinal Injury Association Impairment Scale grade of B for completeness of injury reported more intense NP than those with other grades. Among the SF-36 subitems, NP correlated significantly with bodily pain, general health and mental health. NP in SCI patients was significantly associated with the location of pain, the time period since the injury, surgery and quality-of-life factors. A more detailed understanding of the characteristics of NP may contribute to better strategies for relieving the pain associated with SCI.

  9. Chronic motor cortex stimulation in the treatment of central and neuropathic pain. Correlations between clinical, electrophysiological and anatomical data.

    Science.gov (United States)

    Nguyen, J P; Lefaucheur, J P; Decq, P; Uchiyama, T; Carpentier, A; Fontaine, D; Brugières, P; Pollin, B; Fève, A; Rostaing, S; Cesaro, P; Keravel, Y

    1999-09-01

    Thirty-two patients with refractory central and neuropathic pain of peripheral origin were treated by chronic stimulation of the motor cortex between May 1993 and January 1997. The mean follow-up was 27.3 months. The first 24 patients were operated according to the technique described by Tsubokawa. The last 13 cases (eight new patients and five reinterventions) were operated by a technique including localisation by superficial CT reconstruction of the central region and neuronavigator guidance. The position of the central sulcus was confirmed by the use of intraoperative somatosensory evoked potentials. The somatotopic organisation of the motor cortex was established peroperatively by studying the motor responses at stimulation of the motor cortex through the dura. Ten of the 13 patients with central pain (77%) and ten of the 12 patients with neuropathic facial pain had experienced substantial pain relief (75%). One of the three patients with post-paraplegia pain was clearly improved. A satisfactory result was obtained in one patient with pain related to plexus avulsion and in one patient with pain related to intercostal herpes zooster. None of the patients developed epileptic seizures. The position of the stimulating poles effective on pain corresponded to the somatotopic representation of the motor cortex. The neuronavigator localisation and guidance technique proved to be most useful identifying the appropriate portion of the motor gyrus. It also allowed the establishment of reliable correlations between electrophysiological-clinical and anatomical data which may be used to improve the clinical results and possibly to extend the indications of this technique.

  10. Psychological defensive profile of sciatica patients with neuropathic pain and its relationship to quality of life.

    Science.gov (United States)

    Tutoglu, A; Boyaci, A; Karababa, I F; Koca, I; Kaya, E; Kucuk, A; Yetisgin, A

    2015-09-01

    To identify differences between defense styles and mechanisms in sciatica patients with or without neuropathic pain and their relationship to quality of life. The study included 37 sciatica patients with neuropathic pain (SNP), 36 sciatica patients without neuropathic pain and 38 healthy subjects. Pain severity was measured using the Visual Analogue Scale (VAS). Psychological condition was assessed using the Beck Depression Inventory (BDI) and the Beck Anxiety Inventory (BAI). Defense mechanisms were assessed using a 40-item Defense Style Questionnaire (DSQ-40) and quality of life was assessed using Short Form-36 (SF-36). BDI and BAI scores were significantly higher in the SNP group (p < 0.001). Idealization and immature defense styles, as well as isolation, displacement and somatization were significantly higher in the SNP group (p < 0.05). SF-36 parameters also differed significantly between the groups, with controls having the best scores and the SNP group the worst. In linear regression analysis, acting out and BDI were found to affect the pain domain of the SF-36 (p < 0.001). The acting out defensive style and BDI were independently associated with pain-related quality of life. In the SNP group, significant differences were found in the immature and neurotic styles of the defense mechanisms.

  11. Brain activity modifications following spinal cord stimulation for chronic neuropathic pain: A systematic review.

    Science.gov (United States)

    Bentley, L D; Duarte, R V; Furlong, P L; Ashford, R L; Raphael, J H

    2016-04-01

    Spinal cord stimulation (SCS) is believed to exert supraspinal effects; however, these mechanisms are still far from fully elucidated. This systematic review aims to assess existing neurophysiological and functional neuroimaging literature to reveal current knowledge regarding the effects of SCS for chronic neuropathic pain on brain activity, to identify gaps in knowledge, and to suggest directions for future research. Electronic databases and hand-search of reference lists were employed to identify publications investigating brain activity associated with SCS in patients with chronic neuropathic pain, using neurophysiological and functional neuroimaging techniques (fMRI, PET, MEG, EEG). Studies investigating patients with SCS for chronic neuropathic pain and studying brain activity related to SCS were included. Demographic data (age, gender), study factors (imaging modality, patient diagnoses, pain area, duration of SCS at recording, stimulus used) and brain areas activated were extracted from the included studies. Twenty-four studies were included. Thirteen studies used neuroelectrical imaging techniques, eight studies used haemodynamic imaging techniques, two studies employed both neuroelectrical and haemodynamic techniques separately, and one study investigated cerebral neurobiology. The limited available evidence regarding supraspinal mechanisms of SCS does not allow us to develop any conclusive theories. However, the studies included appear to show an inhibitory effect of SCS on somatosensory evoked potentials, as well as identifying the thalamus and anterior cingulate cortex as potential mediators of the pain experience. The lack of substantial evidence in this area highlights the need for large-scale controlled studies of this kind. © 2015 European Pain Federation - EFIC®

  12. Ketamine PCA for treatment of end-of-life neuropathic pain in pediatrics.

    Science.gov (United States)

    Taylor, Matthew; Jakacki, Regina; May, Carol; Howrie, Denise; Maurer, Scott

    2015-12-01

    Control of neuropathic pain (NP) for children at end of life is challenging. Ketamine improves control of NP, but its use in children is not well described. We describe a retrospective case review of 14 children with terminal prognoses treated with ketamine patient-controlled analgesia (PCA) for management of opioid-refractory NP at the end of life. Median ketamine dose was 0.06 mg/kg/h (range 0.014-0.308 mg/kg/h) with a 0.05 mg/kg (range 0.03-0.5mg/kg) demand dose available every 15 minutes (range 10-60 minutes). All patients noted subjective pain relief with ketamine, and 79% had no adverse effects. Benzodiazepines limited neuropsychiatric side effects. Ketamine treatment arrested dose escalation of opioids in 64% of patients, and 79% were discharged to home hospice. Ketamine PCA is an effective, well-tolerated therapy for opioid-refractory NP in pediatric end-of-life care. © The Author(s) 2014.

  13. Dopaminergic treatment of restless legs syndrome in spinal cord injury patients with neuropathic pain.

    Science.gov (United States)

    Kumru, Hatice; Albu, Sergiu; Vidal, Joan; Barrio, Manuela; Santamaria, Joan

    2016-01-01

    Recent studies report high incidence of restless legs syndrome (RLS) in patients with spinal cord injury (SCI), who may also present pain and sensory disturbances. In the present manuscript, we examine and discuss diagnostic and treatment challenges of comorbid RLS and neuropathic pain (NP) in SCI. We evaluated seven men with a mean age of 55.6 (s.d.=14.0) years, with chronic complete or incomplete SCI at the thoracic or lumbar level, for complaints of sensory disturbances in the legs, which initially were attributed to drug-resistant NP. Because overlapped RLS was suspected, clinical evaluation of NP and RLS, serum ferritin and iron level assessment, and video polysomnographic (VPSG) studies were conducted. Pramipexole (0.18 mg q.d. -1 ) was added to treat RLS, and a follow-up was performed at 2 months. We found that in six subjects the RLS was comorbid with NP and in one subject the symptoms of RLS were misdiagnosed as NP. VPSG revealed periodic limb movements (PLMs) in all patients, including PLMs of the legs, arms or both. Serum ferritin was patients. RLS improved significantly after 2 months with pramipexole. On the basis of current findings, we recommend physicians to be aware of the comorbidity between RLS and NP secondary to SCI to include suitable diagnostic procedures and effective treatments.

  14. Agmatine attenuates neuropathic pain in sciatic nerve ligated rats: modulation by hippocampal sigma receptors.

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    Kotagale, Nandkishor Ramdas; Shirbhate, Saurabh Haridas; Shukla, Pradeep; Ugale, Rajesh Ramesh

    2013-08-15

    Present study investigated the influence of the sigma (σ₁ and σ₂) receptors within hippocampus on the agmatine induced antinociception in neuropathic rats. Animals were subjected to sciatic nerve ligation for induction of neuropathic pain and observed the paw withdrawal latency in response to thermal hyperalgesia, cold allodynia and the mechanical hyperalgesia. Intrahippocampal (i.h.) as well as intraperitoneal (i.p.) administration of agmatine attenuated neuropathic pain in sciatic nerve ligated rats. Intrahippocampal administration of σ₁ agonist (+)-pentazocine or σ₂ agonist PB28 sensitized whereas, σ₁ antagonist BD1063 or σ₂ antagonist SM21 potentiated antinociceptive effect of agmatine. The behavioral effects correlated with hippocampal tumor necrosis factor-α (TNF-α) levels observed by western blot analysis. These results suggest that both the σ₁ and σ₂ receptor subunits within hippocampus play an important role in antinociceptive action of agmatine against neuropathic pain. © 2013 Elsevier B.V. All rights reserved.

  15. Differential transcriptional profiling of damaged and intact adjacent dorsal root ganglia neurons in neuropathic pain.

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    A K Reinhold

    Full Text Available Neuropathic pain, caused by a lesion in the somatosensory system, is a severely impairing mostly chronic disease. While its underlying molecular mechanisms are not thoroughly understood, neuroimmune interactions as well as changes in the pain pathway such as sensitization of nociceptors have been implicated. It has been shown that not only are different cell types involved in generation and maintenance of neuropathic pain, like neurons, immune and glial cells, but, also, intact adjacent neurons are relevant to the process. Here, we describe an experimental approach to discriminate damaged from intact adjacent neurons in the same dorsal root ganglion (DRG using differential fluorescent neuronal labelling and fluorescence-activated cell sorting (FACS. Two fluorescent tracers, Fluoroemerald (FE and 1-dioctadecyl-3,3,3,3-tetramethylindocarbocyanine perchlorate (DiI, were used, whose properties allow us to distinguish between damaged and intact neurons. Subsequent sorting permitted transcriptional analysis of both groups. Results and qPCR validation show a strong regulation in damaged neurons versus contralateral controls as well as a moderate regulation in adjacent neurons. Data for damaged neurons reveal an mRNA expression pattern consistent with established upregulated genes like galanin, which supports our approach. Moreover, novel genes were found strongly regulated such as corticotropin-releasing hormone (CRH, providing novel targets for further research. Differential fluorescent neuronal labelling and sorting allows for a clear distinction between primarily damaged neuropathic neurons and "bystanders," thereby facilitating a more detailed understanding of their respective roles in neuropathic processes in the DRG.

  16. Spinal CPEB-mtROS-CBP signaling pathway contributes to perineural HIV gp120 with ddC-related neuropathic pain in rats.

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    Iida, Takafumi; Yi, Hyun; Liu, Shue; Huang, Wan; Kanda, Hirotsugu; Lubarsky, David A; Hao, Shuanglin

    2016-07-01

    Human immunodeficiency virus (HIV) patients treated with nucleoside reverse transcriptase inhibitors (NRTIs), have been known to develop neuropathic pain. While there has been a major shift away from some neurotoxic NRTIs in current antiretroviral therapy, a large number of HIV patients alive today have previously received them, and many have developed painful peripheral neuropathy. The exact mechanisms by which HIV with NRTIs contribute to the development of neuropathic pain are not known. Previous studies suggest that cytoplasmic polyadenylation element-binding protein (CPEB), reactive oxygen species (ROS), and cAMP-response element-binding protein (CREB)-binding protein (CBP), are involved in the neuroimmunological diseases including inflammatory/neuropathic pain. In this study, we investigated the role of CPEB, mitochondrial ROS (mtROS), or CBP in neuropathic pain induced by HIV envelope protein gp120 combined with antiretroviral drug. The application of recombinant gp120 into the sciatic nerve plus systemic ddC (one of NRTIs) induced mechanical allodynia. Knockdown of CPEB or CBP using intrathecal antisense oligodeoxynucleotide (AS-ODN) reduced mechanical allodynia. Intrathecal mitochondrial superoxide scavenger mito-tempol (Mito-T) increased mechanical withdrawal threshold. Knockdown of CPEB using intrathecal AS-ODN, reduced the up-regulated mitochondrial superoxide in the spinal dorsal horn in rats with gp120 combined with ddC. Intrathecal Mito-T lowered the increased expression of CBP in the spinal dorsal horn. Immunostaining studies showed that neuronal CPEB positive cells were co-localized with MitoSox positive profiles, and that MitoSox positive profiles were co-localized with neuronal CBP. Our studies suggest that neuronal CPEB-mtROS-CBP pathway in the spinal dorsal horn, plays an important role in the gp120/ddC-induced neuropathic pain in rats. Copyright © 2016. Published by Elsevier Inc.

  17. Effect the exercise program on neuropathic pain intensity in patients with paraplegia Spinal Cord Injury

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    Sedghi Goyaghaj N

    2015-11-01

    Full Text Available Background and Objective: Patients with spinal cord injury suffer from continuous and persistent neuropathic pain that has a destructive impact on their quality of life. Exercise therapy is one of the non-pharmacological interventions that is recommended to control chronic pain, This study aimed to determine the effect of exercise program on neuropathic pain intensity in patients with paraplegia Spinal Cord Injury. Materials and Method: This study is a clinical trial.that population was the all of the patients with spinal cord injury, who referred to one of the educational hospitals in Tehran in 2014, 40 patient were selected based on purposive sampling and were randomly allocated into two groups of experimental and control. Exercise program for paraplegia spinal cord injury was implemented in experimental group during twelve 45-60minutes sessions, twice a week. Data collection was done before and one week after the intervention through using personal information form and, The International Spinal Cord Injury Pain Basic Data Set. Data were analyzed with statistical software SPSS19 and Fisher's exact test, Independent samples T-test Paired T-test and Chi square. Results: The mean score of neuropathic pain intensity before the intervention was 8.05 ± 1.51 in intervention group and 7.57 ± 1.21 in the control group. These amounts after the intervention were 5.55 ± 1.61 and 7.37 ± 1.05 respectively (p < 0.001. Conclusion: Results showed that the regular exercise program can reduce neuropathic pain severity in patients with spinal cord injuries and it can be recommended as a non-pharmacological method of pain control in these patients.

  18. Minocycline Does Not Decrease Intensity of Neuropathic Pain Intensity, But Does Improve Its Affective Dimension.

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    Sumitani, Masahiko; Ueda, Hiroshi; Hozumi, Jun; Inoue, Reo; Kogure, Takamichi; Yamada, Yoshitsugu; Kogure, Takamichi

    2016-01-01

    Recent understanding of the neuron-glia communication shed light on an important role of microglia to develop neuropathic pain The analgesic effect of minocycline on neuropathic pain is promising but it remains unclear in clinical settings. This study included 20 patients with neuropathic pain of varied etiologies. We administered 100 mg/day of minocycline for 1 week and then 200 mg/day for 3 weeks, as an open-label adjunct to conventional analgesics. An 11-point numerical rating scale. (NRS) and the short-form McGill Pain Questionnaire (SF-MPQ) were used to evaluate pain severity. The data were collected at baseline and after 4 weeks of therapy and analyzed using the Wilcoxon signed-rank test. All except two of the patients tolerated the full dose of minocycline. There was no significant improvement in the scoring of NRS (5.6 ± 1.2 at baseline vs. 5.3 ± 1.9 at 4 weeks; P =.60). The total score of the SF-MPQ decreased significantly (17.2 ± 7.4 vs. 13.9 ± 9.6; P =.02), particularly in the affective subscale (4.4 ± 2.7 vs. 3.3 ± 3.6; P =.007) but not so in the sensory subscale (12.8 ± 5.2 vs. 10.6 ± 6.2; P =.06). We conclude that minocycline failed to decrease pain intensity but succeeded in reducing the affective dimension associated with neuropathic pain.

  19. A COMBINED EFFECT OF DEXTROMETHORPHAN AND MELATONIN ON NEUROPATHIC PAIN BEHAVIOR IN RATS

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    Wang, Shuxing; Zhang, Lin; Lim, Grewo; Sung, Backil; Tian, Yinghong; Chou, Chiu-Wen; Hernstadt, Hayley; Rusanescu, Gabriel; Ma, Yuxin; Mao, Jianren

    2009-01-01

    Previous study has shown that administration of melatonin into the anterior cingulate cortex contralateral to peripheral nerve injury prevented exacerbation of mechanical allodynia with a concurrent improvement of depression-like behavior in Wistar-Kyoto (WKY) rats, a genetic variation of Wistar rats. In the present study, we examined the effect of the individual versus combined treatment of melatonin and/or dextromethorphan (DM), a clinically available N-methyl-D-aspartate (NMDA) receptor antagonist, on pain behaviors in WKY rats with chronic constriction sciatic nerve injury (CCI). Pain behaviors (thermal hyperalgesia and mechanical allodynia) were established at one week after CCI. WKY rats were then treated intraperitoneally with various doses of melatonin, DM or their combination once daily for the following week. At the end of this one-week treatment, behavioral tests were repeated in these same rats. While DM alone was effective in reducing thermal hyperalgesia at three tested doses (15, 30 or 60 mg/kg), it reduced mechanical allodynia only at high doses (30 or 60 mg/kg). By comparison, administration of melatonin alone was effective in reducing thermal hyperalgesia only at the highest dose (120 mg/kg, but not 30 or 60 mg/kg) tested in this experiment. Melatonin alone failed to reverse allodynia at all three tested doses (30, 60 and 120 mg/kg). However, the combined intraperitoneal administration of melatonin (30 mg/kg) and DM (15 mg/kg) effectively reversed both thermal hyperalgesia and mechanical allodynia although each individual dose alone did not reduce pain behaviors. These results suggest that a combination of melatonin with a clinically available NMDA receptor antagonist might be more effective than either drug alone for the treatment of neuropathic pain. PMID:19595681

  20. Burning Eye Syndrome: Do Neuropathic Pain Mechanisms Underlie Chronic Dry Eye?

    Science.gov (United States)

    Kalangara, Jerry P; Galor, Anat; Levitt, Roy C; Felix, Elizabeth R; Alegret, Ramon; Sarantopoulos, Constantine D

    2016-04-01

    Dry eye is a multi-factorial disorder that manifests with painful ocular symptoms and visual disturbances, which can only be partly attributed to tear dysfunction. This disorder may also involve neuroplasticity in response to neuronal injury. This review will emphasize the key characteristics of dry eye pain and its pathologic mechanisms, making the argument that a subset of dry eye represents a neuropathic pain disorder of the eye, more appropriately called "burning eye syndrome." A literature review was conducted using a PubMed search focusing on dry eye, corneal nociception, and neuropathic pain. Articles were reviewed and those discussing clinical course, pathophysiology, and neuronal regulation of chronic ocular pain as related to dry eye were summarized. We found that there is a discordance between ocular pain and dryness on the ocular surface. Although tear dysfunction may be one of the initial insults, its persistence may be associated with repeated ocular sensory nerve injury leading to an acute-to-chronic pain transition associated with neuropathologic changes (peripheral and central sensitization), neuronal dysfunction, and spontaneous ocular pain. Dry eye is becoming a major health concern due to its increasing incidence, significant morbidity, and economic burden. Recent evidence suggests that a subset of dry eye may be better represented as a chronic neuropathic pain disorder due to its features of dysesthesia, spontaneous pain, allodynia, and hyperalgesia. Future therapies targeted at the underlying neuroplasticity may yield improved efficacy for patients with this subset of dry eye, which we term "burning eye syndrome." © 2015 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Involvement of TRPM2 in a wide range of inflammatory and neuropathic pain mouse models

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    Kanako So

    2015-03-01

    Full Text Available Recent evidence suggests a role of transient receptor potential melastatin 2 (TRPM2 in immune and inflammatory responses. We previously reported that TRPM2 deficiency attenuated inflammatory and neuropathic pain in some pain mouse models, including formalin- or carrageenan-induced inflammatory pain, and peripheral nerve injury-induced neuropathic pain models, while it had no effect on the basal mechanical and thermal nociceptive sensitivities. In this study, we further explored the involvement of TRPM2 in various pain models using TRPM2-knockout mice. There were no differences in the chemonociceptive behaviors evoked by intraplantar injection of capsaicin or hydrogen peroxide between wildtype and TRPM2-knockout mice, while acetic acid-induced writhing behavior was significantly attenuated in TRPM2-knockout mice. In the postoperative incisional pain model, no difference in mechanical allodynia was observed between the two genotypes. By contrast, mechanical allodynia in the monosodium iodoacetate-induced osteoarthritis pain model and the experimental autoimmune encephalomyelitis model were significantly attenuated in TRPM2-knockout mice. Furthermore, mechanical allodynia in paclitaxel-induced peripheral neuropathy and streptozotocin-induced painful diabetic neuropathy models were significantly attenuated in TRPM2-knockout mice. Taken together, these results suggest that TRPM2 plays roles in a wide range of pathological pain models based on peripheral and central neuroinflammation, rather than physiological nociceptive pain.

  2. The role of the immune system in the generation of neuropathic pain.

    Science.gov (United States)

    Calvo, Margarita; Dawes, John M; Bennett, David L H

    2012-07-01

    Persistent pain is a sequela of several neurological conditions with a primary immune basis, such as Guillain-Barré syndrome and multiple sclerosis. Additionally, diverse forms of injury to the peripheral or the central nervous systems--whether traumatic, metabolic, or toxic--result in substantial recruitment and activation of immune cells. This response involves the innate immune system, but evidence also exists of T-lymphocyte recruitment, and in some patient cohorts antibodies to neuronal antigens have been reported. Mediators released by immune cells, such as cytokines, sensitise nociceptive signalling in the peripheral and central nervous systems. Preclinical data suggest an immune pathogenesis of neuropathic pain, but clinical evidence of a central role of the immune system is less clear. An important challenge for the future is to establish to what extent this immune response initiates or maintains neuropathic pain in patients and thus whether it is amenable to therapy. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Blocking mammalian target of rapamycin (mTOR improves neuropathic pain evoked by spinal cord injury

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    Wang Xiaoping

    2016-01-01

    Full Text Available Spinal cord injury (SCI is an extremely serious type of physical trauma observed in clinics. Neuropathic pain resulting from SCI has a lasting and significant impact on most aspects of daily life. Thus, a better understanding of the molecular pathways responsible for the cause of neuropathic pain observed in SCI is important to develop effective therapeutic agents and treatment strategies. Mammalian target of rapamycin (mTOR is a serine/threonine protein kinase that is well known for its critical roles in regulating protein synthesis and growth. Furthermore, compelling evidence supports the notion that widespread dysregulation of mTOR and its downstream pathways are involved in neuropathic pain. Thus, in this study we specifically examined the underlying mechanisms by which mTOR and its signaling pathways are involved in SCI-evoked neuropathic pain in a rat model. Overall, we demonstrated that SCI increased the protein expression of p-mTOR, and mTORmediated- phosphorylation of 4E–binding protein 4 (4E-BP1 and p70 ribosomal S6 protein kinase 1 (S6K1 in the superficial dorsal horn of the spinal cord. Also, we showed that blocking spinal mTOR by intrathecal injection of rapamycin significantly inhibited pain responses induced by mechanical and thermal stimulation. In addition, blocking spinal phosphatidylinositide 3-kinase (p-PI3K pathway significantly attenuated activities of p-mTOR pathways as well as mechanical and thermal hyperalgesia in SCI rats. Moreover, blocking mTOR and PI3K decreased the enhanced levels of substance P and calcitonin gene-related peptide (CGRP in the dorsal horn of SCI rats. We revealed specific signaling pathways leading to SCI-evoked neuropathic pain, including the activation of PI3K, mTOR and its downstream signaling pathways. Targeting one or more of these signaling molecules may present new opportunities for treatment and management of neuropathic pain often observed in patients with SCI.

  4. The effects of transcranial direct current stimulation in patients with neuropathic pain from spinal cord injury.

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    Ngernyam, Niran; Jensen, Mark P; Arayawichanon, Preeda; Auvichayapat, Narong; Tiamkao, Somsak; Janjarasjitt, Suparerk; Punjaruk, Wiyada; Amatachaya, Anuwat; Aree-uea, Benchaporn; Auvichayapat, Paradee

    2015-02-01

    Transcranial direct current stimulation (tDCS) has demonstrated efficacy for reducing neuropathic pain, but the respective mechanisms remain largely unknown. The current study tested the hypothesis that pain reduction with tDCS is associated with an increase in the peak frequency spectrum density in the theta-alpha range. Twenty patients with spinal cord injury and bilateral neuropathic pain received single sessions of both sham and anodal tDCS (2 mA) over the left primary motor area (M1) for 20 min. Treatment order was randomly assigned. Pre- to post-procedure changes in pain intensity and peak frequency of electroencephalogram spectral analysis were compared between treatment conditions. The active treatment condition (anodal tDCS over M1) but not sham treatment resulted in significant decreases in pain intensity. In addition, consistent with the study hypothesis, peak theta-alpha frequency (PTAF) assessed from an electrode placed over the site of stimulation increased more from pre- to post-session among participants in the active tDCS condition, relative to those in the sham tDCS condition. Moreover, we found a significant association between a decrease in pain intensity and an increase in PTAF at the stimulation site. The findings are consistent with the possibility that anodal tDCS over the left M1 may be effective, at least in part, because it results in an increase in M1 cortical excitability, perhaps due to a pain inhibitory effect of motor cortex stimulation that may influence the descending pain modulation system. Future research is needed to determine if there is a causal association between increased left anterior activity and pain reduction. The results provide new findings regarding the effects of tDCS on neuropathic pain and brain oscillation changes. Copyright © 2014 International Federation of Clinical Neurophysiology. All rights reserved.

  5. Percutaneous nerve stimulation in chronic neuropathic pain patients due to spinal cord injury: a pilot study.

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    Kopsky, David Jos; Ettema, Frank Willem Leo; van der Leeden, Marike; Dekker, Joost; Stolwijk-Swüste, Janneke Marjan

    2014-03-01

    The long-term prognosis for neuropathic pain resolution following spinal cord injury (SCI) is often poor. In many SCI patients, neuropathic pain continues or even worsens over time. Thus, new treatment approaches are needed. We conducted a pilot study to evaluate the feasibility and effect of percutaneous (electrical) nerve stimulation (P(E)NS) in SCI patients with chronic neuropathic pain. In 18 weeks, 12 P(E)NS treatments were scheduled. Assessment with questionnaires was performed at baseline (T0), after 8 weeks (T8), 18 weeks (T18), and 12 weeks post-treatment (T30). From 26 screened patients, 17 were included. In total, 91.2% questionnaires were returned, 2 patients dropped out, and 4.2% of the patients reported minor side effects. Pain scores on the week pain diary measured with the numerical rating scale improved significantly at T8, from 6.5 at baseline to 5.4, and were still significantly improved at T18. Pain reduction of ≥ 30% directly after a session was reported in 64.6% sessions. In total, 6 patients experienced reduction in size of the pain areas at T18 and T30, with a mean reduction of 45.8% at T18 and 45.3% at T30. P(E)NS is feasible as an intervention in SCI patients and might have a positive effect on pain reduction in a part of this patient group. © 2013 The Authors Pain Practice © 2013 World Institute of Pain.

  6. A randomized trial of pregabalin in patients with neuropathic pain due to spinal cord injury.

    Science.gov (United States)

    Cardenas, Diana D; Nieshoff, Edward C; Suda, Kota; Goto, Shin-Ichi; Sanin, Luis; Kaneko, Takehiko; Sporn, Jonathan; Parsons, Bruce; Soulsby, Matt; Yang, Ruoyong; Whalen, Ed; Scavone, Joseph M; Suzuki, Makoto M; Knapp, Lloyd E

    2013-02-05

    To assess the efficacy and tolerability of pregabalin for the treatment of central neuropathic pain after spinal cord injury (SCI). Patients with chronic, below-level, neuropathic pain due to SCI were randomized to receive 150 to 600 mg/d pregabalin (n = 108) or matching placebo (n = 112) for 17 weeks. Pain was classified in relation to the neurologic level of injury, defined as the most caudal spinal cord segment with normal sensory and motor function, as above, at, or below level. The primary outcome measure was duration-adjusted average change in pain. Key secondary outcome measures included the change in mean pain score from baseline to end point, the percentage of patients with ≥30% reduction in mean pain score at end point, patient global impression of change scores at end point, and the change in mean pain-related sleep interference score from baseline to end point. Additional outcome measures included the medical outcomes study-sleep scale and the Hospital anxiety and depression scale. Pregabalin treatment resulted in statistically significant improvements over placebo for all primary and key secondary outcome measures. Significant pain improvement was evident as early as week 1 and was sustained throughout the treatment period. Adverse events were consistent with the known safety profile of pregabalin and were mostly mild to moderate in severity. Somnolence and dizziness were most frequently reported. This study demonstrates that pregabalin is effective and well tolerated in patients with neuropathic pain due to SCI. This study provides class I evidence that pregabalin, 150 to 600 mg/d, is effective in reducing duration-adjusted average change in pain compared with baseline in patients with SCI over a 16-week period (p = 0.003, 95% confidence interval = -0.98, -0.20).

  7. Neuropathic pain prevalence following spinal cord injury: A systematic review and meta-analysis.

    Science.gov (United States)

    Burke, D; Fullen, B M; Stokes, D; Lennon, O

    2017-01-01

    Following spinal cord injury (SCI), chronic pain is a common secondary complication with neuropathic pain (NP) cited as one of the most distressing and debilitating conditions leading to poor quality of life, depression and sleep disturbances. Neuropathic pain presenting at or below the level of injury is largely refractory to current pharmacological and physical treatments. No consensus on the prevalence of NP post SCI currently exists, hence this systematic review was undertaken. The review comprised three phases: a methodological assessment of databases [PubMed, Embase, Web of Knowledge, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Library and Physiotherapy Evidence Database (PEDro)] identifying potential papers and screening for inclusion criteria by two independent reviewers; data extraction; and finally rating of internal validity and strength of the evidence, using a published valid and reliable scale. Meta-analysis estimated pooled point prevalence rates using a random effects model. In total, 17 studies involving 2529 patients were included in the review. Overall point prevalence rates for NP were established at 53% (38.58-67.47); 19% (13.26-26.39) for at-level NP and 27% (19.89-34.61) for below-level NP, with high heterogeneity noted (I 2  = 84-93%). Prevalence rates for NP following SCI are high. Future studies should include established definitions, classification systems and assessment tools for NP at defined time points post SCI to follow the trajectory of this problem across the lifespan and include indices of sleep, mood and interference to allow for appropriate, optimal and timely NP management for each patient. WHAT DOES THIS REVIEW ADD?: This is the first systematic review and meta-analysis to record pooled point prevalence of neuropathic pain post spinal cord injury at 53%. Additional pooled analysis shows that neuropathic pain is more common below the level of lesion, in patients with tetraplegia, older patients

  8. A preconditioning nerve lesion inhibits mechanical pain hypersensitivity following subsequent neuropathic injury

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    Wu Ann

    2011-01-01

    Full Text Available Abstract Background A preconditioning stimulus can trigger a neuroprotective phenotype in the nervous system - a preconditioning nerve lesion causes a significant increase in axonal regeneration, and cerebral preconditioning protects against subsequent ischemia. We hypothesized that a preconditioning nerve lesion induces gene/protein modifications, neuronal changes, and immune activation that may affect pain sensation following subsequent nerve injury. We examined whether a preconditioning lesion affects neuropathic pain and neuroinflammation after peripheral nerve injury. Results We found that a preconditioning crush injury to a terminal branch of the sciatic nerve seven days before partial ligation of the sciatic nerve (PSNL; a model of neuropathic pain induced a significant attenuation of pain hypersensitivity, particularly mechanical allodynia. A preconditioning lesion of the tibial nerve induced a long-term significant increase in paw-withdrawal threshold to mechanical stimuli and paw-withdrawal latency to thermal stimuli, after PSNL. A preconditioning lesion of the common peroneal induced a smaller but significant short-term increase in paw-withdrawal threshold to mechanical stimuli, after PSNL. There was no difference between preconditioned and unconditioned animals in neuronal damage and macrophage and T-cell infiltration into the dorsal root ganglia (DRGs or in astrocyte and microglia activation in the spinal dorsal and ventral horns. Conclusions These results suggest that prior exposure to a mild nerve lesion protects against adverse effects of subsequent neuropathic injury, and that this conditioning-induced inhibition of pain hypersensitivity is not dependent on neuroinflammation in DRGs and spinal cord. Identifying the underlying mechanisms may have important implications for the understanding of neuropathic pain due to nerve injury.

  9. Contribution of microglia and astrocytes to the central sensitization, inflammatory and neuropathic pain in the juvenile rat

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    Ikeda Hiroshi

    2012-06-01

    Full Text Available Abstract Background The development of pain after peripheral nerve and tissue injury involves not only neuronal pathways but also immune cells and glia. Central sensitization is thought to be a mechanism for such persistent pain, and ATP involves in the process. We examined the contribution of glia to neuronal excitation in the juvenile rat spinal dorsal horn which is subjected to neuropathic and inflammatory pain. Results In rats subjected to neuropathic pain, immunoreactivity for the microglial marker OX42 was markedly increased. In contrast, in rats subjected to inflammatory pain, immunoreactivity for the astrocyte marker glial fibrillary acidic protein was increased slightly. Optically-recorded neuronal excitation induced by single-pulse stimulation to the dorsal root was augmented in rats subjected to neuropathic and inflammatory pain compared to control rats. The bath application of a glial inhibitor minocycline and a p38 mitogen-activated protein kinase inhibitor SB203580 inhibited the neuronal excitation in rats subjected to neuropathic pain. A specific P2X1,2,3,4 antagonist TNP-ATP largely inhibited the neuronal excitation only in rats subjected to neuropathic pain rats. In contrast, an astroglial toxin L-alpha-aminoadipate, a gap junction blocker carbenoxolone and c-Jun N-terminal kinase inhibitor SP600125 inhibited the neuronal excitation only in rats subjected to inflammatory pain. A greater number of cells in spinal cord slices from rats subjected to neuropathic pain showed Ca2+ signaling in response to puff application of ATP. This Ca2+ signaling was inhibited by minocycline and TNP-ATP. Conclusions These results directly support the notion that microglia is more involved in neuropathic pain and astrocyte in inflammatory pain.

  10. Analgesic effectiveness and tolerability of oral oxycodone/naloxone and pregabalin in patients with lung cancer and neuropathic pain: an observational analysis

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    De Santis S

    2016-07-01

    Full Text Available Stefano De Santis,1 Cristina Borghesi,1 Serena Ricciardi,2 Daniele Giovannoni,1 Alberto Fulvi,2 Maria Rita Migliorino,2 Claudio Marcassa3 1Palliative Care and Cancer Pain Service, Oncological Pulmonary Unit, 2Oncological Pulmonary Unit, San Camillo-Forlanini Hospitals, Rome, 3Cardiologia Fondazione Maugeri IRCCS, Novara, Italy Introduction: Cancer-related pain has a severe negative impact on quality of life. Combination analgesic therapy with oxycodone and pregabalin is effective for treating neuropathic cancer pain. We investigated the efficacy and tolerability of a dose-escalation combination therapy with prolonged-release oxycodone/naloxone (OXN-PR and pregabalin in patients with non-small-cell lung cancer and severe neuropathic pain. Methods: This was a 4-week, open-label, observational study. Patients were treated with OXN-PR and pregabalin. Average pain intensity ([API] measured on a 0–10 numerical rating scale and neuropathic pain (Douleur Neuropathique 4 were assessed at study entry and at follow-up visits. The primary endpoint was response to treatment, defined as a reduction of API at T28 ≥30% from baseline. Secondary endpoints included other efficacy measures, as well as patient satisfaction and quality of life (Brief Pain Inventory Short Form, Hospital Anxiety and Depression Scale, and Symptom Distress Scale; bowel function was also assessed. Results: A total of 56 patients were enrolled. API at baseline was 8.0±0.9, and decreased after 4 weeks by 48% (4.2±1.9; P<0.0001 vs baseline; 46 (82.1% patients responded to treatment. Significant improvements were also reported in number/severity of breakthrough cancer pain episodes (P=0.001, Brief Pain Inventory Short Form (P=0.0002, Symptom Distress Scale (P<0.0001, Hospital Anxiety and Depression Scale depression (P=0.0006 and anxiety (P<0.0001 subscales, and bowel function (P=0.0003. At study end, 37 (66.0% patients were satisfied/very satisfied with the new analgesic treatment

  11. Pain management of opioid-treated cancer patients in hospital settings in Denmark

    DEFF Research Database (Denmark)

    Lundorff, L.; Peuckmann, V.; Sjøgren, Per

    2008-01-01

    AIM: To evaluate the performance and quality of cancer pain management in hospital settings. METHODS: Anaesthesiologists specialised in pain and palliative medicine studied pain management in departments of oncology and surgery. Study days were randomly chosen and patients treated with oral opioids......-treated patients in hospital settings: however, focussing on average pain intensity, the outcome seems favourable compared with other countries. Pain mechanisms were seldom examined and adjuvant drugs were not specifically used for neuropathic pain. Opioid dosing intervals and supplemental opioid doses were most...

  12. Analgesic effect of piracetam on peripheral neuropathic pain induced by chronic constriction injury of sciatic nerve in rats.

    Science.gov (United States)

    Mehta, Ashish K; Bhati, Yogendra; Tripathi, Chakra D; Sharma, Krishna K

    2014-08-01

    Despite immense advances in the treatment strategies, management of neuropathic pain remains unsatisfactory. Piracetam is a prototype of nootropic drugs, used to improve cognitive impairment. The present study was designed to investigate the effect of piracetam on peripheral neuropathic pain in rats. Neuropathic pain was induced by the chronic constriction injury of the sciatic nerve. Following this, piracetam was intraperitoneally administered for 2 weeks in doses of 50, 100 and 200 mg/kg, and pain was assessed by employing the behavioural tests for thermal hyperalgesia (hot plate and tail flick tests) and cold allodynia (acetone test). After the induction of neuropathic pain, significant development of thermal hyperalgesia and cold allodynia was observed. The administration of piracetam (50 mg/kg) did not have any significant effect on all the behavioural tests. Further, piracetam (100 mg/kg) also had no effect on the hot plate and tail flick tests; however it significantly decreased the paw withdrawal duration in the acetone test. Piracetam in a dose of 200 mg/kg significantly modulated neuropathic pain as observed from the increased hot plate and tail flick latencies, and decreased paw withdrawal duration (in acetone test). Therefore, the present study suggests the potential use of piracetam in the treatment of neuropathic pain, which merits further clinical investigation.

  13. Baicalin ameliorates neuropathic pain by suppressing HDAC1 expression in the spinal cord of spinal nerve ligation rats

    Directory of Open Access Journals (Sweden)

    Chen-Hwan Cherng

    2014-08-01

    Conclusion: The present findings suggest that baicalin can ameliorate neuropathic pain by suppressing HDAC1 expression and preventing histone-H3 acetylation in the spinal cord dorsal horn of SNL rats.

  14. Botulinum toxin type A for neuropathic pain in patients with spinal cord injury.

    Science.gov (United States)

    Han, Zee-A; Song, Dae Heon; Oh, Hyun-Mi; Chung, Myung Eun

    2016-04-01

    To evaluate the analgesic effect of botulinum toxin type A (BTX-A) on patients with spinal cord injury-associated neuropathic pain. The effect of BTX-A on 40 patients with spinal cord injury-associated neuropathic pain was investigated using a randomized, double-blind, placebo-controlled design. A 1-time subcutaneous BTX-A (200U) injection was administered to the painful area. Visual analogue scale (VAS) scores (0-100mm), the Korean version of the short-form McGill Pain Questionnaire, and the World Health Organization WHOQOL-BREF quality of life assessment were evaluated prior to treatment and at 4 and 8 weeks after the injection. At 4 and 8 weeks after injection, the VAS score for pain was significantly reduced by 18.6 ± 16.8 and 21.3 ± 26.8, respectively, in the BTX-A group, whereas it was reduced by 2.6 ± 14.6 and 0.3 ± 19.5, respectively, in the placebo group. The pain relief was associated with preservation of motor or sensory function below the neurological level of injury. Among the responders in the BTX-A group, 55% and 45% reported pain relief of 20% or greater at 4 and 8 weeks, respectively, after the injection, whereas only 15% and 10% of the responders in the placebo group reported a similar level of pain relief. Improvements in the score for the physical health domain of the WHOQOL-BREF in the BTX-A group showed a marginal trend toward significance (p = 0.0521) at 4 weeks after the injection. These results indicate that BTX-A may reduce intractable chronic neuropathic pain in patients with spinal cord injury. © 2016 The Authors. Annals of Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.

  15. Melatonin limits paclitaxel‐induced mitochondrial dysfunction in vitro and protects against paclitaxel‐induced neuropathic pain in the rat

    OpenAIRE

    Galley, Helen F.; McCormick, Barry; Wilson, Kirsten L.; Lowes, Damon A.; Colvin, Lesley; Torsney, Carole

    2017-01-01

    Chemotherapy-induced neuropathic pain is a debilitating and common side effect of cancer treatment. Mitochondrial dysfunction associated with oxidative stress in peripheral nerves has been implicated in the underlying mechanism. We investigated the potential of melatonin, a potent antioxidant that preferentially acts within mitochondria, to reduce mitochondrial damage and neuropathic pain resulting from the chemotherapeutic drug paclitaxel. In vitro, paclitaxel caused a 50% reduction of mitoc...

  16. The effect of Neuragen PN® on Neuropathic pain: A randomized, double blind, placebo controlled clinical trial

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    Li Li

    2010-05-01

    Full Text Available Abstract Background A double blind, randomized, placebo controlled study to evaluate the safety and efficacy of the naturally derived topical oil, "Neuragen PN®" for the treatment of neuropathic pain. Methods Sixty participants with plantar cutaneous (foot sole pain due to all cause peripheral neuropathy were recruited from the community. Each subject was randomly assigned to receive one of two treatments (Neuragen PN® or placebo per week in a crossover design. The primary outcome measure was acute spontaneous pain level as reported on a visual analog scale. Results There was an overall pain reduction for both treatments from pre to post application. As compared to the placebo, Neuragen PN® led to significantly (p ® reported pain reduction within 30 minutes. This reduction within 30 minutes occurred in only twenty one of sixty (35.0% subjects receiving the placebo. In a break out analysis of the diabetic only subgroup, 94% of subjects in the Neuragen PN® group achieved pain reduction within 30 minutes vs 11.0% of the placebo group. No adverse events were observed. Conclusions This randomized, placebo controlled, clinical trial with crossover design revealed that the naturally derived oil, Neuragen PN®, provided significant relief from neuropathic pain in an all cause neuropathy group. Participants with diabetes within this group experienced similar pain relief. Trial registration ISRCTN registered: ISRCTN13226601

  17. Pharmacological kynurenine 3-monooxygenase enzyme inhibition significantly reduces neuropathic pain in a rat model.

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    Rojewska, Ewelina; Piotrowska, Anna; Makuch, Wioletta; Przewlocka, Barbara; Mika, Joanna

    2016-03-01

    Recent studies have highlighted the involvement of the kynurenine pathway in the pathology of neurodegenerative diseases, but the role of this system in neuropathic pain requires further extensive research. Therefore, the aim of our study was to examine the role of kynurenine 3-monooxygenase (Kmo), an enzyme that is important in this pathway, in a rat model of neuropathy after chronic constriction injury (CCI) to the sciatic nerve. For the first time, we demonstrated that the injury-induced increase in the Kmo mRNA levels in the spinal cord and the dorsal root ganglia (DRG) was reduced by chronic administration of the microglial inhibitor minocycline and that this effect paralleled a decrease in the intensity of neuropathy. Further, minocycline administration alleviated the lipopolysaccharide (LPS)-induced upregulation of Kmo mRNA expression in microglial cell cultures. Moreover, we demonstrated that not only indirect inhibition of Kmo using minocycline but also direct inhibition using Kmo inhibitors (Ro61-6048 and JM6) decreased neuropathic pain intensity on the third and the seventh days after CCI. Chronic Ro61-6048 administration diminished the protein levels of IBA-1, IL-6, IL-1beta and NOS2 in the spinal cord and/or the DRG. Both Kmo inhibitors potentiated the analgesic properties of morphine. In summary, our data suggest that in neuropathic pain model, inhibiting Kmo function significantly reduces pain symptoms and enhances the effectiveness of morphine. The results of our studies show that the kynurenine pathway is an important mediator of neuropathic pain pathology and indicate that Kmo represents a novel pharmacological target for the treatment of neuropathy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Microsurgical Drezotomy for Neuropathic Pain after Spinal Cord Injury: Long Term Results in a Patient

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    Acevedo González, Juan Carlos; López Cárdenas, Gloria Viviana; Berbeo Calderón, Miguel Enrique; Zorro Guio, Óscar; Díaz Orduz, Roberto Carlos; Feo Lee, Óscar

    2012-01-01

    70 % of patients with spinal cord injuries are chronic and disabling neuropathic pain. This article presents the 23 years-old patient case, who suffered an infrasegmentary severe pain by spinal cord trauma. We performed neurosurgical treatment of pain. Drezotomy is selective section of nociceptive fibers in the spinal segments involved. The patient has 24 months of complete improvement and discontinuation of analgesics. Un 70 % de pacientes con lesión medular tiene dolor neuropático crónic...

  19. [Effectiveness and safety of oxcarbazepine in chronic neuropathic pain: a study of 40 cases].

    Science.gov (United States)

    Fenollosa-Vázquez, P; Canós-Verdecho, M A; Núñez-Cornejo, C; Pallarés-Delgado, J

    Neuropathic pain (NP) often fails to respond to the commonly established analgesic treatment. This fact, together with the existence of side effects, has led to the need to evaluate the analgesic effectiveness of antiepileptic drugs, which, as in the case of oxcarbazepine (OXC), are a valid alternative. The aim of this study was to evaluate the effectiveness and safety of OXC in patients suffering from chronic NP. We conducted a prospective, open study involving a series of 40 patients diagnosed with a long history of NP, which was previously resistant to different kinds of treatment with anticonvulsants, non-steroidal anti-inflammatory (NSAI) drugs, opiates and adjuncts. Patients were treated with OXC and they were evaluated in both the basal (prior to treatment) and final visits (after treatment) by means of the visual analogue scale (VAS), SF-McGill questionnaire and the Lattinen test. The patient's general impression of the result was also obtained. The statistical analysis was performed by calculating the "effect size", by computing Cohen's d. Treatment with OXC diminishes different symptomatic variations of this pain, but especially so in the case of lancinating discharges (d = 0.87, important effect) and burning pain (d = 0.60, moderate-important effect), although the allodynia (d = 0.48, moderate effect) also improved with treatment. In the opinion of the patients themselves, response to treatment was good or very good in 50% of cases. The chief side effects observed were dizziness, drowsiness and abdominal upsets. OXC can be seen as a therapeutic alternative to be taken very much into account in patients with NP having different aetiologies; it has a good benefit-risk ratio and is a form of treatment that is well accepted by patients.

  20. Inhibition of 2-arachydonoylgycerol degradation attenuates orofacial neuropathic pain in trigeminal nerve-injured mice.

    Science.gov (United States)

    Kamimura, Rantaro; Hossain, Mohammad Z; Unno, Shumpei; Ando, Hiroshi; Masuda, Yuji; Takahashi, Kojiro; Otake, Masanori; Saito, Isao; Kitagawa, Junichi

    2018-03-24

    Current therapeutics are not effective for orofacial neuropathic pain, and better options are needed. The present study used inferior orbital nerve (ION)-injured mice to investigate the effect of inhibiting monoacylglycerol lipase (MAGL), an enzyme that degrades the major endocannabinoid 2-arachydonoylgycerol (2-AG) in orofacial neuropathic pain. The head-withdrawal threshold to mechanical stimulation of the whisker pad was reduced on days 3, 5, and 7 after ION injury. Injection of JZL184, a selective inhibitor of MAGL, on day 7 after ION injury attenuated the reduction in head-withdrawal threshold at 2 h after administration. Moreover, the numbers of MAGL-immunoreactive neurons in the trigeminal subnucleus caudalis (Vc) and upper cervical spinal cord (C1-C2) were significantly greater in ION-injured mice than in sham-operated mice but were reduced after administration of JZL184. The increase in MAGL immunoreactivity suggests that increased 2-AG production is followed by rapid enzymatic degradation of 2-AG. JZL184 inhibited this degradation and thus increased 2-AG concentration in the brain, particularly in the Vc and C1-C2 regions, thus attenuating pain. Our findings suggest that inhibition of 2-AG degradation by MAGL inhibitors is a promising therapeutic option for treatment of orofacial neuropathic pain.

  1. Neuropathic pain mechanisms in patients with chronic sports injuries: a diagnostic model useful in sports medicine?

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    van Wilgen, Cornelis P; Keizer, Doeke

    2011-01-01

    The pathophysiology of chronic sports injuries such as overuse or tendinopathy remains largely unknown. With this exploratory study, we aim to detect signs of sensitization of the nervous system. Sensitization is an indication of the involvement of neuropathic mechanisms in patients with chronic sports injuries. Sensory descriptors were assessed by means of a neuropathic pain questionnaire (DN4-interview) and by three methods of sensory testing. The test results were integrated in a scoring system. Patients were recruited from an outpatient clinic of a University Medical Centre and at primary care physical therapy practices. Fifteen athletes with a unilateral chronic sports injury were included. All subjects filled out the seven-items of the DN4-interview to assess sensory descriptors. Next, the presence of brush-evoked allodynia was assessed and pain thresholds with Von Frey monofilaments and a pressure algometer were measured in all patients to determine signs of sensitization. Based on the scoring system, in 4 out of 15 patients (27%) the presence of sensitization could be detected. In two other patients, signs of hypoalgesia were observed. The involvement of sensitization as an explanation for the pain in chronic sports injuries is credible in a considerable proportion of patients. With respect to treatment, the establishment of such neuropathic pain mechanisms is of clinical significance. Wiley Periodicals, Inc.

  2. Synaptic Conversion of Chloride-Dependent Synapses in Spinal Nociceptive Circuits: Roles in Neuropathic Pain

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    Mark S. Cooper

    2011-01-01

    Full Text Available Electrophysiological conversion of chloride-dependent synapses from inhibitory to excitatory function, as a result of aberrant neuronal chloride homeostasis, is a known mechanism for the genesis of neuropathic pain. This paper examines theoretically how this type of synaptic conversion can disrupt circuit logic in spinal nociceptive circuits. First, a mathematical scaling factor is developed to represent local aberration in chloride electrochemical driving potential. Using this mathematical scaling factor, electrophysiological symbols are developed to represent the magnitude of synaptic conversion within nociceptive circuits. When inserted into a nociceptive circuit diagram, these symbols assist in understanding the generation of neuropathic pain associated with the collapse of transmembrane chloride gradients. A more generalized scaling factor is also derived to represent the interplay of chloride and bicarbonate driving potentials on the function of GABAergic and glycinergic synapses. These mathematical and symbolic representations of synaptic conversion help illustrate the critical role that anion driving potentials play in the transduction of pain. Using these representations, we discuss ramifications of glial-mediated synaptic conversion in the genesis, and treatment, of neuropathic pain.

  3. Aberrant TRPV1 expression in heat hyperalgesia associated with trigeminal neuropathic pain.

    Science.gov (United States)

    Urano, Hiroko; Ara, Toshiaki; Fujinami, Yoshiaki; Hiraoka, B Yukihiro

    2012-01-01

    Trigeminal neuropathic pain is a facial pain syndrome associated with trigeminal nerve injury. However, the mechanism of trigeminal neuropathic pain is poorly understood. This study aimed to determine the role of transient receptor potential vanilloid 1 (TRPV1) in heat hyperalgesia in a trigeminal neuropathic pain model. We evaluated nociceptive responses to mechanical and heat stimuli using a partial infraorbital nerve ligation (pIONL) model. Withdrawal responses to mechanical and heat stimuli to vibrissal pads (VP) were assessed using von Frey filaments and a thermal stimulator equipped with a heat probe, respectively. Changes in withdrawal responses were measured after subcutaneous injection of the TRP channel antagonist capsazepine. In addition, the expression of TRPV1 in the trigeminal ganglia was examined. Mechanical allodynia and heat hyperalgesia were observed in VP by pIONL. Capsazepine suppressed heat hyperalgesia but not mechanical allodynia. The number of TRPV1-positive neurons in the trigeminal ganglia was significantly increased in the large-diameter-cell group. These results suggest that TRPV1 plays an important role in the heat hyperalgesia observed in the pIONL model.

  4. Orofacial neuropathic pain mouse model induced by Trigeminal Inflammatory Compression (TIC of the infraorbital nerve

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    Ma Fei

    2012-12-01

    Full Text Available Abstract Background Trigeminal neuropathic pain attacks can be excruciating for patients, even after being lightly touched. Although there are rodent trigeminal nerve research models to study orofacial pain, few models have been applied to studies in mice. A mouse trigeminal inflammatory compression (TIC model is introduced here which successfully and reliably promotes vibrissal whisker pad hypersensitivity. Results The chronic orofacial neuropathic pain model is induced after surgical placement of chromic gut suture in the infraorbital nerve fissure in the maxillary bone. Slight compression and chemical effects of the chromic gut suture on the portion of the infraorbital nerve contacted cause mild nerve trauma. Nerve edema is observed in the contacting infraorbital nerve bundle as well as macrophage infiltration in the trigeminal ganglia. Centrally in the spinal trigeminal nucleus, increased immunoreactivity for an activated microglial marker is evident (OX42, postoperative day 70. Mechanical thresholds of the affected whisker pad are significantly decreased on day 3 after chromic gut suture placement, persisting at least 10 weeks. The mechanical allodynia is reversed by suppression of microglial activation. Cold allodynia was detected at 4 weeks. Conclusions A simple, effective, and reproducible chronic mouse model mimicking clinical orofacial neuropathic pain (Type 2 is induced by placing chromic gut suture between the infraorbital nerve and the maxillary bone. The method produces mild inflammatory compression with significant continuous mechanical allodynia persisting at least 10 weeks and cold allodynia measureable at 4 weeks.

  5. Prevalence of pain and relative diagnostic performance of screening tools for neuropathic pain in cancer patients: A cross-sectional study.

    Science.gov (United States)

    Pérez, C; Sánchez-Martínez, N; Ballesteros, A; Blanco, T; Collazo, A; González, F; Villoria, J

    2015-07-01

    Neuropathic pain can be overlooked in cancer patients. The advent of screening tools can help in recognizing it. However, little is known about their relative diagnostic performance and factors that affect it. This study evaluated the prevalence of neuropathic pain using several diagnostic strategies in cancer patients undergoing chemotherapy. Patients attending the Oncology Unit of the investigators' site to continue their chemotherapy schedule were systematically screened for this cross-sectional study. Before starting chemotherapy drugs, pain specialists made a clinical diagnosis of neuropathic pain (either disease related, treatment related or comorbid) and medical oncologists administered three validated screening tools. Their relative diagnostic performance and the impact of some pain features on it were analysed using multivariate statistical methods. From a total of 358 patients, 194 (54.2%) suffered from pain and 73 (20.4%) had a clinical diagnosis of pure neuropathic or mixed pain. Among the screening tools, the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) was more specific (93.4%), although less sensitive (68.1%) than the Douleur Neuropathique in 4 Questions (DN4) (sensitivity: 87.5%, specificity: 88.4%). Interestingly, the specificities of these two instruments did not differ in patients with mild pain, while the DN4 remained to be more sensitive than the LANSS regardless of pain severity. Neuropathic pain is common in cancer patients undergoing chemotherapy. The DN4 might be of great help for the early detection of patients at risk because of incipient chemotherapy-related neuropathies and the LANSS to rule out neuropathic pain in patients with complex pain conditions. © 2014 The Authors. European Journal of Pain published by John Wiley & Sons Ltd on behalf of European Pain Federation - EFIC®.

  6. The CanPain SCI Clinical Practice Guidelines for Rehabilitation Management of Neuropathic Pain after Spinal Cord: screening and diagnosis recommendations.

    Science.gov (United States)

    Mehta, S; Guy, S D; Bryce, T N; Craven, B C; Finnerup, N B; Hitzig, S L; Orenczuk, S; Siddall, P J; Widerström-Noga, E; Casalino, A; Côté, I; Harvey, D; Kras-Dupuis, A; Lau, B; Middleton, J W; Moulin, D E; O'Connell, C; Parrent, A G; Potter, P; Short, C; Teasell, R; Townson, A; Truchon, C; Wolfe, D; Bradbury, C L; Loh, E

    2016-08-01

    Clinical practice guidelines. To develop the first Canadian clinical practice guidelines for screening and diagnosis of neuropathic pain in people with spinal cord injury (SCI). The guidelines are relevant for inpatient and outpatient SCI rehabilitation settings in Canada. The CanPainSCI Working Group reviewed evidence to address clinical questions regarding screening and diagnosis of neuropathic pain after SCI. A consensus process was followed to achieve agreement on recommendations and clinical considerations. Twelve recommendations, based on expert consensus, were developed for the screening and diagnosis of neuropathic pain after SCI. The recommendations address methods for assessment, documentation tools, team member accountability, frequency of screening and considerations for diagnostic investigation. Important clinical considerations accompany each recommendation. The expert Working Group developed recommendations for the screening and diagnosis of neuropathic pain after SCI that should be used to inform practice.

  7. Viral vectors encoding endomorphins and serine histogranin attenuate neuropathic pain symptoms after spinal cord injury in rats.

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    Nasirinezhad, Farinaz; Gajavelli, Shyam; Priddy, Blake; Jergova, Stanislava; Zadina, James; Sagen, Jacqueline

    2015-01-07

    The treatment of spinal cord injury (SCI)-induced neuropathic pain presents a challenging healthcare problem. The lack of available robust pharmacological treatments underscores the need for novel therapeutic methods and approaches. Due to the complex character of neuropathic pain following SCI, therapies targeting multiple mechanisms may be a better choice for obtaining sufficient long-term pain relief. Previous studies in our lab showed analgesic effects using combinations of an NMDA antagonist peptide [Ser1]histogranin (SHG), and the mu-opioid peptides endomorphins (EMs), in several pain models. As an alternative to drug therapy, this study evaluated the analgesic potential of these peptides when delivered via gene therapy. Lentiviruses encoding SHG and EM-1 and EM-2 were intraspinally injected, either singly or in combination, into rats with clip compression SCI 2 weeks following injury. Treated animals showed significant reduction in mechanical and thermal hypersensitivity, compared to control groups injected with GFP vector only. The antinociceptive effects of individually injected components were modest, but the combination of EMs and SHG produced robust and sustained antinociception. The onset of the analgesic effects was observed between 1-5 weeks post-injection and sustained without decrement for at least 7 weeks. No adverse effects on locomotor function were observed. The involvement of SHG and EMs in the observed antinociception was confirmed by pharmacologic inhibition using intrathecal injection of either the opioid antagonist naloxone or an anti-SHG antibody. Immunohistochemical analysis showed the presence of SHG and EMs in the spinal cord of treated animals, and immunodot-blot analysis of CSF confirmed the presence of these peptides in injected animals. In a separate group of rats, delayed injection of viral vectors was performed in order to mimic a more likely clinical scenario. Comparable and sustained antinociceptive effects were observed in

  8. Uso da metadona no tratamento da dor neuropática não-oncológica: relato de casos Uso de la metadona en el tratamiento del dolor neuropático no oncológico: relato de casos Methadone to treat non-oncologic neuropathic pain: case reports

    Directory of Open Access Journals (Sweden)

    Jeane Pereira da Silva Juver

    2005-08-01

    , opioide sintético, semejante a la morfina, por vía oral, es referido como alternativa en el tratamiento del dolor neuropático por su acción antagonista no competitiva sobre los receptores NMDA. El objetivo de este estudio es evaluar el uso de la metadona en el tratamiento de pacientes portadores de dolores crónicos de origen neuropático no oncológico, que no mejoraron con los tratamientos clásicos. RELATO DE LOS CASOS: Se presentan siete casos en los cuales la dosis de metadona fue titulada en consultas subsiguientes y los variables resultados de la intensidad álgica según la escala de aspectos, efectos colaterales y mejora de la capacidad funcional fueron analizados en el 1º, 7º, 14º, 30º y 180º días después del inicio del uso de la medicación. Hubo reducción de los resultados de la intensidad álgica y la ocurrencia de efectos colaterales como constipación, sedación, náuseas, cefalea e insomnio. No fueron observados efectos colaterales del tipo euforia, sudoresis, mioclonias, retención urinaria, reducción de la libido y depresión respiratoria. CONCLUSIONES: Los pacientes presentaron respuesta considerada satisfactoria al uso de la medicación, en bajas dosis; control de los efectos colaterales con medidas simples y mejora representativa de la capacidad funcional. La inclusión de la metadona, en las condiciones de este estudio, se mostró una opción eficaz, segura y de bajo valor, para el tratamiento de los dolores de origen neuropáticos no oncológicos.BACKGROUND AND OBJECTIVES: This report includes seven patients with chronic non-oncologic neuropathic pain who have not responded to classic approaches with tricyclic antidepressant and anticonvulsant drugs. Oral methadone, a synthetic opioid similar to morphine, is referred as alternative to treat neuropathic pain due to its non-competitive antagonist action on NMDA receptors. This study aimed at evaluating methadone to treat chronic non-oncologic neuropathic pain patients who have not

  9. Neuroimmune-Driven Neuropathic Pain Establishment: A Focus on Gender Differences

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    Vincenzo Coraggio

    2018-01-01

    Full Text Available The role of neuroinflammatory cells in the establishment of neuropathic pain has been investigated in depth in the last few years. In particular, microglia have been shown to be key players in the induction of tactile allodynia, as they release proinflammatory molecules that, in turn, sensitize nociceptive neurons within the spinal cord. However, the role of peripheral immune cells such as macrophages, infiltrating monocytes, mast cells, and T-cells has been highlighted in the last few studies, even though the data are still conflicting and need to be clarified. Intriguingly, the central (microglia and peripheral (T-cell-adaptive immune cells that orchestrate maladaptive process-driven neuropathic pain seem to be involved in a gender-dependent manner. In this review, we highlight the role of the microglia and peripheral immune cells in chronic degenerative disease associated with neuro-immune-inflammatory processes.

  10. Internal and external factors affecting the development of neuropathic pain in rodents. Is it all about pain?

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    Vissers, K; De Jongh, R; Hoffmann, V; Heylen, R; Crul, B; Meert, T

    2003-12-01

    It is important to know the factors that will influence animal models of neuropathic pain. A good reproducibility and predictability in different strains of animals for a given test increases the clinical relevance and possible targeting. An obligatory requirement for enabling comparisons of results of different origin is a meticulous definition of the specific sensitivities of a model for neuropathic pain and a description of the test conditions. Factors influencing neuropathic pain behavior can be subdivided in external and internal factors. The most important external factors are; timing of the measurement of pain after induction of neuropathy, circadian rhythms, seasonal influences, air humidity, influence of order of testing, diet, social variables, housing and manipulation, cage density, sexual activity, external stress factors, and influences of the experimenter. The internal factors are related to the type of animal, its genetic background, gender, age, and the presence of homeostatic adaptation mechanisms to specific situations or stress. In practice, the behavioral presentations to pain depend on the combination of genetic and environmental factors such as accepted social behavior. It also depends on the use of genetic manipulation of the animals such as in transgenic animals. These make the interpretation of data even more difficult. Differences of pain behavior between in- and outbred animals will be better understood by using modern analysis techniques. Substrains of animals with a high likelihood for developing neuropathic pain make the unraveling of specific pathophysiological mechanisms possible. Concerning the effect of stress on pain, it is important to differentiate between external and internal stress such as social coping behavior. The individual dealing with this stress is species sensitive, and depends on the genotype and the social learning. In the future, histo-immunological and genetic analysis will highlight similarities of the different

  11. Bortezomib induces neuropathic pain through protein kinase C-mediated activation of presynaptic NMDA receptors in the spinal cord.

    Science.gov (United States)

    Xie, Jing-Dun; Chen, Shao-Rui; Chen, Hong; Pan, Hui-Lin

    2017-09-01

    Chemotherapeutic drugs, including bortezomib, often cause painful peripheral neuropathy, which is a severe dose-limiting adverse effect experienced by many cancer patients. The glutamate N-methyl-d-aspartate receptors (NMDARs) at the spinal cord level are critically involved in the synaptic plasticity associated with neuropathic pain. In this study, we determined whether treatment with bortezomib, a proteasome inhibitor, affects the NMDAR activity of spinal dorsal horn neurons. Systemic treatment with bortezomib in rats did not significantly affect postsynaptic NMDAR currents elicited by puff application of NMDA directly to dorsal horn neurons. Bortezomib treatment markedly increased the baseline frequency of miniature excitatory postsynaptic currents (EPSCs), which was completely normalized by the NMDAR antagonist 2-amino-5-phosphonopentanoic acid (AP5). AP5 also reduced the amplitude of monosynaptic EPSCs evoked by dorsal root stimulation in bortezomib-treated, but not vehicle-treated, rats. Furthermore, inhibition of protein kinase C (PKC) with chelerythrine fully reversed the increased frequency of miniature EPSCs and the amplitude of evoked EPSCs in bortezomib-treated rats. Intrathecal injection of AP5 and chelerythrine both profoundly attenuated mechanical allodynia and hyperalgesia induced by systemic treatment with bortezomib. In addition, treatment with bortezomib induced striking membrane translocation of PKC-βII, PKC-δ, and PKC-ε in the dorsal root ganglion. Our findings indicate that bortezomib treatment potentiates nociceptive input from primary afferent nerves via PKC-mediated tonic activation of presynaptic NMDARs. Targeting presynaptic NMDARs and PKC at the spinal cord level may be an effective strategy for treating chemotherapy-induced neuropathic pain. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. A Randomized, Placebo-Controlled, Crossover Trial of Cannabis Cigarettes in Neuropathic Pain

    Science.gov (United States)

    Wilsey, Barth; Marcotte, Thomas; Tsodikov, Alexander; Millman, Jeanna; Bentley, Heather; Gouaux, Ben; Fishman, Scott

    2016-01-01

    The Food and Drug Administration (FDA), Substance Abuse and Mental Health Services Administration (SAMHSA), and the National Institute for Drug Abuse (NIDA) report that no sound scientific studies support the medicinal use of cannabis. Despite this lack of scientific validation, many patients routinely use “medical marijuana,” and in many cases this use is for pain related to nerve injury. We conducted a double-blinded, placebo-controlled, crossover study evaluating the analgesic efficacy of smoking cannabis for neuropathic pain. Thirty-eight patients with central and peripheral neuropathic pain underwent a standardized procedure for smoking either high-dose (7%), low-dose (3.5%), or placebo cannabis. In addition to the primary outcome of pain intensity, secondary outcome measures included evoked pain using heat-pain threshold, sensitivity to light touch, psychoactive side effects, and neuropsychological performance. A mixed linear model demonstrated an analgesic response to smoking cannabis. No effect on evoked pain was seen. Psychoactive effects were minimal and well-tolerated, with some acute cognitive effects, particularly with memory, at higher doses. PMID:18403272

  13. Quantitative sensory testing of neuropathic pain patients: potential mechanistic and therapeutic implications.

    Science.gov (United States)

    Pfau, Doreen B; Geber, Christian; Birklein, Frank; Treede, Rolf-Detlef

    2012-06-01

    Quantitative sensory testing (QST) is a widely accepted tool to investigate somatosensory changes in pain patients. Many different protocols have been developed in clinical pain research within recent years. In this review, we provide an overview of QST and tested neuroanatomical pathways, including peripheral and central structures. Based on research studies using animal and human surrogate models of neuropathic pain, possible underlying mechanisms of chronic pain are discussed. Clinically, QST may be useful for 1) the identification of subgroups of patients with different underlying pain mechanisms; 2) prediction of therapeutic outcomes; and 3) quantification of therapeutic interventions in pain therapy. Combined with sensory mapping, QST may provide useful information on the site of neural damage and on mechanisms of positive and negative somatosensory abnormalities. The use of QST in individual patients for diagnostic purposes leading to individualized therapy is an interesting concept, but needs further validation.

  14. The role of glia in the spinal cord in neuropathic and inflammatory pain.

    Science.gov (United States)

    Old, Elizabeth Amy; Clark, Anna K; Malcangio, Marzia

    2015-01-01

    Chronic pain, both inflammatory and neuropathic, is a debilitating condition in which the pain experience persists after the painful stimulus has resolved. The efficacy of current treatment strategies using opioids, NSAIDS and anticonvulsants is limited by the extensive side effects observed in patients, underlining the necessity for novel therapeutic targets. Preclinical models of chronic pain have recently provided evidence for a critical role played by glial cells in the mechanisms underlying the chronicity of pain, both at the site of damage in the periphery and in the dorsal horn of the spinal cord. Here microglia and astrocytes respond to the increased input from the periphery and change morphology, increase in number and release pro-nociceptive mediators such as ATP, cytokines and chemokines. These gliotransmitters can sensitise neurons by activation of their cognate receptors thereby contributing to central sensitization which is fundamental for the generation of allodynia, hyperalgesia and spontaneous pain.

  15. Antinociceptive effects of topical mepivacaine in a rat model of HIV-associated peripheral neuropathic pain

    Directory of Open Access Journals (Sweden)

    Sagen J

    2016-06-01

    Full Text Available Jacqueline Sagen, Daniel A Castellanos,† Aldric T Hama The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, USA †Daniel A Castellanos passed away on April 14, 2010 Background: A consequence of HIV infection is sensory neuropathy, a debilitating condition that degrades the quality of life of HIV patients. Furthermore, life-extending antiretroviral treatment may exacerbate HIV sensory neuropathy. Analgesics that relieve other neuropathic pains show little or no efficacy in ameliorating HIV sensory neuropathy. Thus, there is a need for analgesics for people with this particular pain. While lidocaine is used in the management of painful peripheral neuropathies, another local anesthetic mepivacaine, with a potentially improved bioavailability, could be utilized for the management of HIV neuropathic pain.Methods: The efficacy of topical anesthetics was evaluated in a preclinical rodent model of painful peripheral neuropathy induced by epineural administration of the HIV envelope protein gp120 delivered using saturated oxidized cellulose implanted around the sciatic nerve. Beginning at 2 weeks following gp120 administration, the effects of local anesthetics topically applied via gauze pads were tested on heat and mechanical hyperalgesia in the hind paw. Rats were tested using several concentrations of mepivacaine or lidocaine during the following 2 weeks.Results: By 2 weeks following epineural gp120 implantation, the ipsilateral hind paw developed significant hypersensitivity to noxious pressure and heat hyperalgesia. A short-lasting, concentration-dependent amelioration of pressure and heat hyperalgesia was observed following topical application of mepivacaine to the ipsilateral plantar hind paw. By contrast, topical lidocaine ameliorated heat hyperalgesia in a concentration-dependent manner but not pressure hyperalgesia. Equipotent concentrations of mepivacaine and lidocaine applied topically to the

  16. Identification of neuropathic pain in patients with neck/upper limb pain: application of a grading system and screening tools.

    Science.gov (United States)

    Tampin, Brigitte; Briffa, Noelle Kathryn; Goucke, Roger; Slater, Helen

    2013-12-01

    The Neuropathic Pain Special Interest Group (NeuPSIG) of the International Association for the Study of Pain has proposed a grading system for the presence of neuropathic pain (NeP) using the following categories: no NeP, possible, probable, or definite NeP. To further evaluate this system, we investigated patients with neck/upper limb pain with a suspected nerve lesion, to explore: (i) the clinical application of this grading system; (ii) the suitability of 2 NeP questionnaires (Leeds Assessment of Neuropathic Symptoms and Signs pain scale [LANSS] and the painDETECT questionnaire [PD-Q]) in identifying NeP in this patient cohort; and (iii) the level of agreement in identifying NeP between the NeuPSIG classification system and 2 NeP questionnaires. Patients (n = 152; age 52 ± 12 years; 53% male) completed the PD-Q and LANSS questionnaire and underwent a comprehensive clinical examination. The NeuPSIG grading system proved feasible for application in this patient cohort, although it required considerable time and expertise. Both questionnaires failed to identify a large number of patients with clinically classified definite NeP (LANSS sensitivity 22%, specificity 88%; PD-Q sensitivity 64%, specificity 62%). These lowered sensitivity scores contrast with those from the original PD-Q and LANSS validation studies and may reflect differences in the clinical characteristics of the study populations. The diagnostic accuracy of LANSS and PD-Q for the identification of NeP in patients with neck/upper limb pain appears limited. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  17. Effects of Danggui Sini decoction on neuropathic pain: experimental studies and clinical pharmacological significance of inhibiting glial activation and proinflammatory cytokines in the spinal cord
.

    Science.gov (United States)

    Liu, Ming; Qiang, Qiu Hong; Ling, Qian; Yu, Chang Xi; Li, Xuejun; Liu, Suhuan; Yang, Shuyu

    2017-05-01

    Neuropathic pain responds poorly to drug treatments. Partial relief is achieved in only about half of the patients. Danggui Sini decoction (DSD), an aqueous extract of Angelica sinensis, Ramulus Cinnamomi, and Radix Puerariae, has been used extensively in China to treat inflammatory and ischemic diseases. The current study examined the putative effects of DSD on neuropathic pain. We used two commonly-used animal models: chronic constriction injury (CCI) and diabetic neuropathy for the study. And we examined effects of DSD on pain response, activation of microglia and astroglia in spinal dorsal horn, and expression of proinflammatory cytokines in the spinal cord. Consecutive intragastric administration of DSD (25 - 100 mg/kg) for 10 days inhibited the mechanical and thermal nociceptive response induced by CCI and diabetes without interfering with the normal pain response. Meanwhile, in both models, DSD inhibited the over-expression of specific markers for microglia (Iba-1) and astroglia (GFAP) activation in the spinal dorsal horn. DSD also reduced the elevated nuclear NF-κB level and inhibited the up-regulation of proinflammatory cytokines, such as IL-6, IL-1β, and TNF-α, in the spinal cord. DSD can alleviate CCI and diabetes-induced neuropathic pain, and its effectiveness might be due to the inhibition of neuroinflammation in the spinal dorsal horn. The anti-inflammation effect of DSD may be related to the suppression of spinal NF-κB activation and/or cytokines expression.
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  18. The mechanism of neurofeedback training for treatment of central neuropathic pain in paraplegia: a pilot study.

    Science.gov (United States)

    Hassan, Muhammad Abul; Fraser, Matthew; Conway, Bernard A; Allan, David B; Vuckovic, Aleksandra

    2015-10-13

    Central neuropathic pain has a prevalence of 40% in patients with spinal cord injury. Electroencephalography (EEG) studies showed that this type of pain has identifiable signatures, that could potentially be targeted by a neuromodulation therapy. The aim of the study was to investigate the putative mechanism of neurofeedback training on central neuropathic pain and its underlying brain signatures in patients with chronic paraplegia. Patients' EEG activity was modulated from the sensory-motor cortex, electrode location C3/Cz/C4/P4 in up to 40 training sessions Results. Six out of seven patients reported immediate reduction of pain during neurofeedback training. Best results were achieved with suppressing Ɵ and higher β (20-30 Hz) power and reinforcing α power at C4. Four patients reported clinically significant long-term reduction of pain (>30%) which lasted at least a month beyond the therapy. EEG during neurofeedback revealed a wide spread modulation of power in all three frequency bands accompanied with changes in the coherence most notable in the beta band. The standardized low resolution electromagnetic tomography analysis of EEG before and after neurofeedback therapy showed the statistically significant reduction of power in beta frequency band in all tested patients. Areas with reduced power included the Dorsolateral Prefrontal Cortex, the Anterior Cingulate Cortex and the Insular Cortex. Neurofeedback training produces both immediate and longer term reduction of central neuropathic pain that is accompanied with a measurable short and long term modulation of cortical activity. Controlled trials are required to confirm the efficacy of this neurofeedback protocol on treatment of pain. The study is a registered UKCRN clinical trial Nr 9824.

  19. Ameliorative potential of Ocimum sanctum in chronic constriction injury-induced neuropathic pain in rats

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    GURPREET KAUR

    2015-03-01

    Full Text Available The present study was designed to investigate the ameliorative potential of Ocimumsanctum and its saponin rich fraction in chronic constriction injury-induced neuropathic pain in rats. The chronic constriction injury was induced by placing four loose ligatures around the sciatic nerve, proximal to its trifurcation. The mechanical hyperalgesia, cold allodynia, paw heat hyperalgesia and cold tail hyperalgesia were assessed by performing the pinprick, acetone, hot plate and cold tail immersion tests, respectively. Biochemically, the tissue thio-barbituric acid reactive species, super-oxide anion content (markers of oxidative stress and total calcium levels were measured. Chronic constriction injury was associated with the development of mechanical hyperalgesia, cold allodynia, heat and cold hyperalgesia along with an increase in oxidative stress and calcium levels. However, administration of Ocimumsanctum (100 and 200 mg/kg p.o. and its saponin rich fraction (100 and 200 mg/kg p.o. for 14 days significantly attenuated chronic constriction injury-induced neuropathic pain as well as decrease the oxidative stress and calcium levels. It may be concluded that saponin rich fraction of Ocimum sanctum has ameliorative potential in attenuating painful neuropathic state, which may be attributed to a decrease in oxidative stress and calcium levels.

  20. The contribution of TRPM8 and TRPA1 channels to cold allodynia and neuropathic pain.

    Science.gov (United States)

    Caspani, Ombretta; Zurborg, Sandra; Labuz, Dominika; Heppenstall, Paul A

    2009-10-08

    Cold allodynia is a common feature of neuropathic pain however the underlying mechanisms of this enhanced sensitivity to cold are not known. Recently the transient receptor potential (TRP) channels TRPM8 and TRPA1 have been identified and proposed to be molecular sensors for cold. Here we have investigated the expression of TRPM8 and TRPA1 mRNA in the dorsal root ganglia (DRG) and examined the cold sensitivity of peripheral sensory neurons in the chronic construction injury (CCI) model of neuropathic pain in mice.In behavioral experiments, chronic constriction injury (CCI) of the sciatic nerve induced a hypersensitivity to both cold and the TRPM8 agonist menthol that developed 2 days post injury and remained stable for at least 2 weeks. Using quantitative RT-PCR and in situ hybridization we examined the expression of TRPM8 and TRPA1 in DRG. Both channels displayed significantly reduced expression levels after injury with no change in their distribution pattern in identified neuronal subpopulations. Furthermore, in calcium imaging experiments, we detected no alterations in the number of cold or menthol responsive neurons in the DRG, or in the functional properties of cold transduction following injury. Intriguingly however, responses to the TRPA1 agonist mustard oil were strongly reduced.Our results indicate that injured sensory neurons do not develop abnormal cold sensitivity after chronic constriction injury and that alterations in the expression of TRPM8 and TRPA1 are unlikely to contribute directly to the pathogenesis of cold allodynia in this neuropathic pain model.

  1. Eligibility audits for the randomized neuropathic bone pain trial (TROG 96.05)

    International Nuclear Information System (INIS)

    Roos, D.E.; Turner, S.L.

    2000-01-01

    In February 1996 the Trans-Tasman Radiation Oncology Group (TROG) initiated a two-arm, multicentre, prospective randomized trial on radiotherapy for neuropathic pain due to bone metastases (TROG 96.05). This trial compares the response to a single 8-Gy fraction with 20 Gy in five fractions. The accrual target is 270 patients. In order to evaluate compliance with eligibility criteria after approximately 1 year of accrual, an independent audit of the first 42 randomized patients was commissioned. This found that only one of these patients did not have genuine neuropathic pain, but that this patient and seven others (19%) had infringements of other eligibility/exclusion criteria for the trial. Accordingly it was decided to continue the full audit up to 90 patients. This detected no further patients without genuine neuropathic pain, and found only one other eligibility infringement (1/48; 2%). It is concluded that this quality assurance (QA) measure undertaken early in the trial led to significantly improved clinician awareness of, and compliance with, eligibility/exclusion criteria. It also enabled an accurate comparison of outcome data for all randomized versus all eligible patients at the time of the preplanned first interim analysis at 90 patients. In view of the excellent compliance demonstrated in the second audit, a one-in-five sampling is proposed for future audits from centres that have already accrued at least five consecutive eligible patients. This is consistent with TROG QA guidelines now operational. Copyright (2000) Blackwell Science Pty Ltd

  2. Methodology for self-report of rest pain (or spontaneous pain) vs evoked pain in chronic neuropathic conditions: a prospective observational pilot study

    OpenAIRE

    He, David; Grant, Brian; Holden, Ronald R.; Gilron, Ian

    2017-01-01

    Abstract. Introduction:. The distinction between pain at rest and pain evoked by touch or movement has important clinical implications and may be associated with different mechanisms. However, current methods of clinical pain assessment pay little attention to directly distinguishing between these contrasting components of symptom burden. Objectives:. We developed the 10-item “Functional Impact of Neuropathic Evoked and Spontaneous Symptom Evaluation” questionnaire designed to distinguish ...

  3. Management of neuropathic pain following treatment for breast cancer in the absence of recurrence: a challenge for the radiation oncologist

    International Nuclear Information System (INIS)

    Clubb, B.

    2004-01-01

    This report reviews various management options for treatment-induced neuropathic pain in breast cancer. First-line options include tricyclic antidepressants and anticonvulsant drugs. Opioids should be prescribed according to published guidelines. Second-line treatments include lignocaine, mexiletine and ketamine. Sympatholytic therapies are available to patients with features of chronic regional pain syndrome. Anti-inflammatory agents are used for neurogenic inflammation. Surgical interventions are considered for refractory neuropathic pain. Interdisciplinary management is appropriate when persisting pain causes physical and psychosocial disabilities. Copyright (2004) Blackwell Science Pty Ltd

  4. Sensory Symptom Profiles of Patients With Neuropathic Pain After Spinal Cord Injury.

    Science.gov (United States)

    Soler, Maria Dolors; Moriña, David; Rodríguez, Neus; Saurí, Joan; Vidal, Joan; Navarro, Albert; Navarro, Xavier

    2017-09-01

    Individuals experiencing neuropathic pain (NP) after spinal cord injury (SCI) present with a variety of pain descriptors in different combinations and at different intensities. These sensory features form distinct patterns, known as sensory symptom profiles. In the present cross-sectional study, we have used a multivariate statistical method (multiple correspondence analysis) to categorize the sensory symptom profiles of a cohort of 338 patients with at-level or below-level NP after SCI. We also investigated possible associations between positive neuropathic symptoms and features of the neurological lesion. The majority of participants had a combination of pain descriptors, with 59% presenting with 3 or 4 pain subtypes. No significant associations were found between specific pain profiles and etiology or clinical degree of the neurological lesion. Furthermore, similar symptom profiles were seen in patients with at-level and below-level NP. The most frequent pattern observed in patients with cervical SCI consisted predominantly of electric shocks and tingling, without burning, pressure pain, or allodynia. Classification of SCI-NP patients into the 5 groups identified in the present study based on their distinct sensory symptom profiles may allow identification of those most likely to respond to a specific analgesic approach.

  5. Neuropathic Pain Causes Pyramidal Neuronal Hyperactivity in the Anterior Cingulate Cortex

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    Ruohe Zhao

    2018-04-01

    Full Text Available The anterior cingulate cortex (ACC is thought to be important for acute pain perception as well as the development of chronic pain after peripheral nerve injury. Nevertheless, how ACC neurons respond to sensory stimulation under chronic pain states is not well understood. Here, we used an in vivo two-photon imaging technique to monitor the activity of individual neurons in the ACC of awake, head restrained mice. Calcium imaging in the dorsal ACC revealed robust somatic activity in layer 5 (L5 pyramidal neurons in response to peripheral noxious stimuli, and the degree of evoked activity was correlated with the intensity of noxious stimulation. Furthermore, the activation of ACC neurons occurred bilaterally upon noxious stimulation to either contralateral or ipsilateral hind paws. Notably, with nerve injury-induced neuropathic pain in one limb, L5 pyramidal neurons in both sides of the ACC showed enhanced activity in the absence or presence of pain stimuli. These results reveal hyperactivity of L5 pyramidal neurons in the bilateral ACC during the development of neuropathic pain.

  6. Pharmacological Management of Chronic Neuropathic Pain – Consensus Statement and Guidelines from the Canadian Pain Society

    Directory of Open Access Journals (Sweden)

    DE Moulin

    2007-01-01

    Full Text Available Neuropathic pain (NeP, generated by disorders of the peripheral and central nervous system, can be particularly severe and disabling. Prevalence estimates indicate that 2% to 3% of the population in the developed world suffer from NeP, which suggests that up to one million Canadians have this disabling condition. Evidence-based guidelines for the pharmacological management of NeP are therefore urgently needed. Randomized, controlled trials, systematic reviews and existing guidelines focusing on the pharmacological management of NeP were evaluated at a consensus meeting. Medications are recommended in the guidelines if their analgesic efficacy was supported by at least one methodologically sound, randomized, controlled trial showing significant benefit relative to placebo or another relevant control group. Recommendations for treatment are based on degree of evidence of analgesic efficacy, safety, ease of use and cost-effectiveness. Analgesic agents recommended for first-line treatments are certain antidepressants (tricyclics and anticonvulsants (gabapentin and pregabalin. Second-line treatments recommended are serotonin noradrenaline reuptake inhibitors and topical lidocaine. Tramadol and controlled-release opioid analgesics are recommended as third-line treatments for moderate to severe pain. Recommended fourth-line treatments include cannabinoids, methadone and anticonvulsants with lesser evidence of efficacy, such as lamotrigine, topiramate and valproic acid. Treatment must be individualized for each patient based on efficacy, side-effect profile and drug accessibility, including cost. Further studies are required to examine head-to-head comparisons among analgesics, combinations of analgesics, long-term outcomes, and treatment of pediatric and central NeP.

  7. Duloxetine in patients with central neuropathic pain caused by spinal cord injury or stroke: a randomized, double-blind, placebo-controlled trial

    NARCIS (Netherlands)

    Vranken, J. H.; Hollmann, M. W.; van der Vegt, M. H.; Kruis, M. R.; Heesen, M.; Vos, K.; Pijl, A. J.; Dijkgraaf, M. G. W.

    2011-01-01

    The mechanisms underlying central neuropathic pain are poorly understood. Pain inhibitory mechanisms including sertononergic and norepinephrine systems may be dysfunctional. In this randomized, double-blinded, placebo-controlled trial we evaluated the effects of duloxetine on pain relief

  8. Experimental Gene Therapy with Serine-Histogranin and Endomorphin 1 for the Treatment of Chronic Neuropathic Pain

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    Stanislava Jergova

    2017-12-01

    Full Text Available The insufficient pain relief provided by current pharmacotherapy for chronic neuropathic pain is a serious medical problem. The enhanced glutamate signaling via NMDA receptors appears to be one of the key events in the development of chronic pain. Although effective, clinical use of systemic NMDA antagonists is limited by adverse effects such as hallucinations and motor dysfunction. Opioids are also potent analgesics but their chronic use is accompanied by tolerance and risk of addiction. However, combination of NMDA antagonists and opioids seems to provide a stable pain relieve at subthreshold doses of both substances, eliminating development of side effects. Our previous research showed that combined delivery of NMDA antagonist Serine histrogranin (SHG and endomorphin1 (EM1 leads to attenuation of acute and chronic pain. The aim of this study was to design and evaluate an analgesic potency of the gene construct encoding SHG and EM1. Constructs with 1SHG copy in combination with EM1, 1SHG/EM1, and 6SHG/EM1 were intraspinally injected to animals with peripheral nerve injury-induced pain (chronic constriction injury, CCI or spinal cord injury induced pain (clip compression model, SCI and tactile and cold allodynia were evaluated. AAV2/8 particles were used for gene delivery. The results demonstrated 6SHG/EM1 as the most efficient for alleviation of pain-related behavior. The effect was observed up to 8 weeks in SCI animals, suggesting the lack of tolerance of possible synergistic effect between SHG and EM1. Intrathecal injection of SHG antibody or naloxone attenuated the analgesic effect in treated animals. Biochemical and histochemical evaluation confirmed the presence of both peptides in the spinal tissue. The results of this study showed that the injection of AAV vectors encoding combined SHG/EM constructs can provide long term attenuation of pain without overt adverse side effects. This approach may provide better treatment options for

  9. Specific brain morphometric changes in spinal cord injury with and without neuropathic pain

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    Tom B. Mole

    2014-01-01

    Full Text Available Why only certain patients develop debilitating pain after spinal chord injury and whether structural brain changes are implicated remain unknown. The aim of this study was to determine if patients with chronic, neuropathic below-level pain have specific cerebral changes compared to those who remain pain-free. Voxel-based morphometry of high resolution, T1-weighted images was performed on three subject groups comprising patients with pain (SCI-P, n = 18, patients without pain (SCI-N, n = 12 and age- and sex-matched controls (n = 18. The SCI-P group was first compared directly with the SCI-N group and then subsequently with controls. Overall, grey and white matter changes dependent on the presence of pain were revealed. Significant changes were found within the somatosensory cortex and also in corticospinal tracts and visual-processing areas. When the SCI-P group was directly compared with the SCI-N group, reduced grey matter volume was found in the deafferented leg area of the somatosensory cortex bilaterally. This region negatively correlated with pain intensity. Relative to controls, grey matter in this paracentral primary sensory cortex was decreased in SCI-P but conversely increased in SCI-N. When compared with controls, discrepant corticospinal tract white matter reductions were found in SCI-P and in SCI-N. In the visual cortex, SCI-N showed increased grey matter, whilst the SCI-N showed reduced white matter. In conclusion, structural changes in SCI are related to the presence and degree of below-level pain and involve but are not limited to the sensorimotor cortices. Pain-related structural plasticity may hold clinical implications for the prevention and management of refractory neuropathic pain.

  10. Specific brain morphometric changes in spinal cord injury with and without neuropathic pain.

    Science.gov (United States)

    Mole, Tom B; MacIver, Kate; Sluming, Vanessa; Ridgway, Gerard R; Nurmikko, Turo J

    2014-01-01

    Why only certain patients develop debilitating pain after spinal chord injury and whether structural brain changes are implicated remain unknown. The aim of this study was to determine if patients with chronic, neuropathic below-level pain have specific cerebral changes compared to those who remain pain-free. Voxel-based morphometry of high resolution, T1-weighted images was performed on three subject groups comprising patients with pain (SCI-P, n = 18), patients without pain (SCI-N, n = 12) and age- and sex-matched controls (n = 18). The SCI-P group was first compared directly with the SCI-N group and then subsequently with controls. Overall, grey and white matter changes dependent on the presence of pain were revealed. Significant changes were found within the somatosensory cortex and also in corticospinal tracts and visual-processing areas. When the SCI-P group was directly compared with the SCI-N group, reduced grey matter volume was found in the deafferented leg area of the somatosensory cortex bilaterally. This region negatively correlated with pain intensity. Relative to controls, grey matter in this paracentral primary sensory cortex was decreased in SCI-P but conversely increased in SCI-N. When compared with controls, discrepant corticospinal tract white matter reductions were found in SCI-P and in SCI-N. In the visual cortex, SCI-N showed increased grey matter, whilst the SCI-N showed reduced white matter. In conclusion, structural changes in SCI are related to the presence and degree of below-level pain and involve but are not limited to the sensorimotor cortices. Pain-related structural plasticity may hold clinical implications for the prevention and management of refractory neuropathic pain.

  11. Gene expression profile of sodium channel subunits in the anterior cingulate cortex during experimental paclitaxel-induced neuropathic pain in mice

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    Willias Masocha

    2016-11-01

    Full Text Available Paclitaxel, a chemotherapeutic agent, causes neuropathic pain whose supraspinal pathophysiology is not fully understood. Dysregulation of sodium channel expression, studied mainly in the periphery and spinal cord level, contributes to the pathogenesis of neuropathic pain. We examined gene expression of sodium channel (Nav subunits by real time polymerase chain reaction (PCR in the anterior cingulate cortex (ACC at day 7 post first administration of paclitaxel, when mice had developed paclitaxel-induced thermal hyperalgesia. The ACC was chosen because increased activity in the ACC has been observed during neuropathic pain. In the ACC of vehicle-treated animals the threshold cycle (Ct values for Nav1.4, Nav1.5, Nav1.7, Nav1.8 and Nav1.9 were above 30 and/or not detectable in some samples. Thus, comparison in mRNA expression between untreated control, vehicle-treated and paclitaxel treated animals was done for Nav1.1, Nav1.2, Nav1.3, Nav1.6, Nax as well as Navβ1–Navβ4. There were no differences in the transcript levels of Nav1.1–Nav1.3, Nav1.6, Nax, Navβ1–Navβ3 between untreated and vehicle-treated mice, however, vehicle treatment increased Navβ4 expression. Paclitaxel treatment significantly increased the mRNA expression of Nav1.1, Nav1.2, Nav1.6 and Nax, but not Nav1.3, sodium channel alpha subunits compared to vehicle-treated animals. Treatment with paclitaxel significantly increased the expression of Navβ1 and Navβ3, but not Navβ2 and Navβ4, sodium channel beta subunits compared to vehicle-treated animals. These findings suggest that during paclitaxel-induced neuropathic pain (PINP there is differential upregulation of sodium channels in the ACC, which might contribute to the increased neuronal activity observed in the area during neuropathic pain.

  12. Feasibility of Topical Applications of Natural High-Concentration Capsaicinoid Solutions in Patients with Peripheral Neuropathic Pain: A Retrospective Analysis

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    Fanny Bauchy

    2016-01-01

    Full Text Available Background. Capsaicin, one of several capsaicinoid compounds, is a potent TRPV1 agonist. Topical application at high concentration (high concentration, >1% induces a reversible disappearance of epidermal free nerve endings and is used to treat peripheral neuropathic pain (PNP. While the benefit of low-concentration capsaicin remains controversial, the 8%-capsaicin patch (Qutenza®, 2010, Astellas, Netherlands has shown its effectiveness. This patch is, however, costly and natural high-concentration capsaicinoid solutions may represent a cheaper alternative to pure capsaicin. Methods. In this retrospective study, 149 patients were screened, 132 were included with a diagnosis of neuropathic pain, and eighty-four were retained in the final analyses (median age: 57.5 years [IQR25–75: 44.7–67.1], male/female: 30/54 with PNP who were treated with topical applications of natural high-concentration capsaicinoid solutions (total number of applications: 137. Indications were postsurgical PNP (85.7% and nonsurgical PNP (14.3% (posttraumatic, HIV-related, postherpetic, and radicular PNP. Objectives. To assess the feasibility of topical applications of natural high-concentration capsaicinoid solutions for the treatment of PNP. Results. The median treated area was 250 cm2 [IQR25–75: 144–531]. The median amount of capsaicinoids was 55.1 mg [IQR25–75: 28.7–76.5] per plaster and the median concentration was 172.3 μg/cm2 [IQR25–75: 127.6–255.2]. Most patients had local adverse effects on the day of treatment, such as mild to moderate burning pain and erythema. 13.6–19.4% of the patients experienced severe pain or erythema. Following treatment, 62.5% of patients reported a lower pain intensity or a smaller pain surface, and 35% reported a sustained pain relief lasting for at least 4 weeks. Conclusion. Analgesic topical treatment with natural high-concentration capsaicinoid is feasible and may represent a low cost alternative to alleviate

  13. Minocycline Enhances the Effectiveness of Nociceptin/Orphanin FQ during Neuropathic Pain

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    Katarzyna Popiolek-Barczyk

    2014-01-01

    Full Text Available Nociceptin/orphanin FQ (N/OFQ antinociception, which is mediated selectively by the N/OFQ peptide receptor (NOP, was demonstrated in pain models. In this study, we determine the role of activated microglia on the analgesic effects of N/OFQ in a rat model of neuropathic pain induced by chronic constriction injury (CCI to the sciatic nerve. Repeated 7-day administration of minocycline (30 mg/kg i.p., a drug that affects microglial activation, significantly reduced pain in CCI-exposed rats and it potentiates the analgesic effects of administered N/OFQ (2.5–5 μg i.t.. Minocycline also downregulates the nerve injury-induced upregulation of NOP protein in the dorsal lumbar spinal cord. Our in vitro study showed that minocycline reduced NOP mRNA, but not protein, level in rat primary microglial cell cultures. In [35S]GTPγS binding assays we have shown that minocycline increases the spinal N/OFQ-stimulated NOP signaling. We suggest that the modulation of the N/OFQ system by minocycline is due to the potentiation of its neuronal antinociceptive activity and weakening of the microglial cell activation. This effect is beneficial for pain relief, and these results suggest new targets for the development of drugs that are effective against neuropathic pain.

  14. D-Aspartate drinking solution alleviates pain and cognitive impairment in neuropathic mice.

    Science.gov (United States)

    Palazzo, Enza; Luongo, Livio; Guida, Francesca; Marabese, Ida; Romano, Rosaria; Iannotta, Monica; Rossi, Francesca; D'Aniello, Antimo; Stella, Luigi; Marmo, Federica; Usiello, Alessandro; de Bartolomeis, Andrea; Maione, Sabatino; de Novellis, Vito

    2016-07-01

    D-Aspartate (D-Asp) is a free D-amino acid detected in multiple brain regions and putative precursor of endogenous N-methyl-D-aspartate (NMDA) acting as agonist at NMDA receptors. In this study, we investigated whether D-Asp (20 mM) in drinking solution for 1 month affects pain responses and pain-related emotional, and cognitive behaviour in a model of neuropathic pain induced by the spared nerve injury (SNI) of the sciatic nerve in mice. SNI mice developed mechanical allodynia and motor coordination impairment 30 days after SNI surgery. SNI mice showed cognitive impairment, anxiety and depression-like behaviour, reduced sociability in the three chamber sociability paradigm, increased expression of NR2B subunit of NMDA receptor and Homer 1a in the medial prefrontal cortex (mPFC). The expression of (post synaptic density) PSD-95 and Shank 1was instead unaffected in the mPFC of the SNI mice. Treatment with D-Asp drinking solution, started right after the SNI (day 0), alleviated mechanical allodynia, improved cognition and motor coordination and increased social interaction. D-Asp also restored the levels of extracellular D-Asp, Homer 1a and NR2B subunit of the NMDA receptor to physiological levels and reduced Shank1 and PSD-95 protein levels in the mPFC. Amitriptyline, a tricyclic antidepressant used also to alleviate neuropathic pain in humans, reverted mechanical allodynia and cognitive impairment, and unlike D-Asp, was effective in reducing depression and anxiety-like behaviour in the SNI mice and increased PSD protein level. Altogether these findings demonstrate that D-Asp improves sensorial, motor and cognitive-like symptoms related to chronic pain possibly through glutamate neurotransmission normalization in neuropathic mice.

  15. The use of 10-kilohertz spinal cord stimulation in a cohort of patients with chronic neuropathic limb pain refractory to medical management.

    Science.gov (United States)

    Al-Kaisy, Adnan; Palmisani, Stefano; Smith, Tom; Harris, Stephany; Pang, David

    2015-01-01

    It is the purpose of this study to document our experience with the use of a 10-kHz high-frequency spinal cord stimulation (SCS) device for the relief of neuropathic pain of the upper and lower limbs. A retrospective chart review was performed of all patients treated with the 10-kHz high-frequency SCS system for neuropathic pain (upper or lower limb) refractory to conventional treatment. All patients underwent a trial with one or two eight-contact percutaneous leads using 50-Hz traditional stimulation. If ≥ 80% paresthesia coverage of the painful area with traditional SCS was obtained, high-frequency 10-kHz SCS was used. Patients who had a significant reduction in pain score (≥ 50%) at the end of the trial received a permanent implant and were then followed for up to six months. Outcome measures included a numeric rating scale for pain, the Brief Pain Inventory, health-related quality of life (EQ-5D), the Pain Catastrophizing Scale, and patient satisfaction. Fifteen patients completed a trial of high-frequency 10-kHz SCS. Eleven patients proceeded to permanent implantation. Ten of the 11 patients who proceeded to full implantation had significant reductions in all of the collected outcome variables at one, three, and six months. In this small cohort of patients, high-frequency 10-kHz SCS reduced pain and improved quality of life. However, before we can conclude that high-frequency 10-kHz SCS for neuropathic pain of the upper and lower extremities is efficacious, a large-scale multicenter observational study should be performed to corroborate our small retrospective study. © 2014 International Neuromodulation Society.

  16. Upregulation of neuronal kynurenine 3-monooxygenase mediates depression-like behavior in a mouse model of neuropathic pain.

    Science.gov (United States)

    Laumet, Geoffroy; Zhou, Wenjun; Dantzer, Robert; Edralin, Jules D; Huo, XiaoJiao; Budac, David P; O'Connor, Jason C; Lee, Anna W; Heijnen, Cobi J; Kavelaars, Annemieke

    2017-11-01

    Pain and depression often co-occur, but the underlying mechanisms have not been elucidated. Here, we used the spared nerve injury (SNI) model in mice to induce both neuropathic pain and depression-like behavior. We investigated whether brain interleukin (IL)-1 signaling and activity of kynurenine 3-monoxygenase (KMO), a key enzyme for metabolism of kynurenine into the neurotoxic NMDA receptor agonist quinolinic acid, are necessary for comorbid neuropathic pain and depression-like behavior. SNI mice showed increased expression levels of Il1b and Kmo mRNA in the contralateral side of the brain. The SNI-induced increase of Kmo mRNA was associated with increased KMO protein and elevated quinolinic acid and reduced kynurenic acid in the contralateral hippocampus. The increase in KMO-protein in response to SNI mostly took place in hippocampal NeuN-positive neurons rather than microglia. Inhibition of brain IL-1 signaling by intracerebroventricular administration of IL-1 receptor antagonist after SNI prevented the increase in Kmo mRNA and depression-like behavior measured by forced swim test. However, inhibition of brain IL-1 signaling has no effect on mechanical allodynia. In addition, intracerebroventricular administration of the KMO inhibitor Ro 61-8048 abrogated depression-like behavior without affecting mechanical allodynia after SNI. We show for the first time that the development of depression-like behavior in the SNI model requires brain IL-1 signaling and activation of neuronal KMO, while pain is independent of this pathway. Inhibition of KMO may represent a promising target for treating depression. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Diagnostic Accuracy of the Slump Test for Identifying Neuropathic Pain in the Lower Limb.

    Science.gov (United States)

    Urban, Lawrence M; MacNeil, Brian J

    2015-08-01

    Diagnostic accuracy study with nonconsecutive enrollment. To assess the diagnostic accuracy of the slump test for neuropathic pain (NeP) in those with low to moderate levels of chronic low back pain (LBP), and to determine whether accuracy of the slump test improves by adding anatomical or qualitative pain descriptors. Neuropathic pain has been linked with poor outcomes, likely due to inadequate diagnosis, which precludes treatment specific for NeP. Current diagnostic approaches are time consuming or lack accuracy. A convenience sample of 21 individuals with LBP, with or without radiating leg pain, was recruited. A standardized neurosensory examination was used to determine the reference diagnosis for NeP. Afterward, the slump test was administered to all participants. Reports of pain location and quality produced during the slump test were recorded. The neurosensory examination designated 11 of the 21 participants with LBP/sciatica as having NeP. The slump test displayed high sensitivity (0.91), moderate specificity (0.70), a positive likelihood ratio of 3.03, and a negative likelihood ratio of 0.13. Adding the criterion of pain below the knee significantly increased specificity to 1.00 (positive likelihood ratio = 11.9). Pain-quality descriptors did not improve diagnostic accuracy. The slump test was highly sensitive in identifying NeP within the study sample. Adding a pain-location criterion improved specificity. Combining the diagnostic outcomes was very effective in identifying all those without NeP and half of those with NeP. Limitations arising from the small and narrow spectrum of participants with LBP/sciatica sampled within the study prevent application of the findings to a wider population. Diagnosis, level 4-.

  18. Multiple sites and actions of gabapentin-induced relief of ongoing experimental neuropathic pain.

    Science.gov (United States)

    Bannister, Kirsty; Qu, Chaoling; Navratilova, Edita; Oyarzo, Janice; Xie, Jennifer Yanhua; King, Tamara; Dickenson, Anthony H; Porreca, Frank

    2017-12-01

    Gabapentin (GBP) is a first-line therapy for neuropathic pain, but its mechanisms and sites of action remain uncertain. We investigated GBP-induced modulation of neuropathic pain following spinal nerve ligation (SNL) in rats. Intravenous or intrathecal GBP reversed evoked mechanical hypersensitivity and produced conditioned place preference (CPP) and dopamine (DA) release in the nucleus accumbens (NAc) selectively in SNL rats. Spinal GBP also significantly inhibited dorsal horn wide-dynamic-range neuronal responses to a range of evoked stimuli in SNL rats. By contrast, GBP microinjected bilaterally into the rostral anterior cingulate cortex (rACC), produced CPP, and elicited NAc DA release selectively in SNL rats but did not reverse tactile allodynia and had marginal effects on wide-dynamic-range neuronal activity. Moreover, blockade of endogenous opioid signaling in the rACC prevented intravenous GBP-induced CPP and NAc DA release but failed to block its inhibition of tactile allodynia. Gabapentin, therefore, can potentially act to produce its pain relieving effects by (a) inhibition of injury-induced spinal neuronal excitability, evoked hypersensitivity, and ongoing pain and (b) selective supraspinal modulation of affective qualities of pain, without alteration of reflexive behaviors. Consistent with previous findings of pain relief from nonopioid analgesics, GBP requires engagement of rACC endogenous opioid circuits and downstream activation of mesolimbic reward circuits reflected in learned pain-motivated behaviors. These findings support the partial separation of sensory and affective dimensions of pain in this experimental model and suggest that modulation of affective-motivational qualities of pain may be the preferential mechanism of GBP's analgesic effects in patients.

  19. The inhibition of nitric oxide-activated poly(ADP-ribose) synthetase attenuates transsynaptic alteration of spinal cord dorsal horn neurons and neuropathic pain in the rat.

    Science.gov (United States)

    Mao, J; Price, D D; Zhu, J; Lu, J; Mayer, D J

    1997-09-01

    Transsynaptic alteration of spinal cord dorsal horn neurons characterized by hyperchromatosis of cytoplasm and nucleoplasm (so-called 'dark' neurons) occurs in a rat model of neuropathic pain induced by chronic constriction injury (CCI) of the common sciatic nerve. The incidence of dark neurons in CCI rats has been proposed to be mediated by glutamate-induced neurotoxicity. In the present study, we examined whether the inhibition of the nitric oxide (NO)-activated poly(ADP-ribose) synthetase (PARS), a nuclear enzyme critical to glutamate-induced neurotoxicity, would both reduce the incidence of dark neurons and attenuate behavioral manifestations of neuropathic pain in CCI rats. Dark neurons were observed bilaterally (with ipsilateral predominance) within the spinal cord dorsal horn, particularly in laminae I-II, of rats 8 days after unilateral sciatic nerve ligation as compared to sham operated rats. The number of dark neurons in the dorsal horn was dose-dependently reduced in CCI rats receiving once daily intrathecal (i.t.) treatment with the PARS inhibitor benzamide (200 or 400 nmol, but not 100 nmol benzamide or saline) for 7 days. Consistent with the histological improvement, thermal hyperalgesia, mechanical hyperalgesia, and low threshold mechano-allodynia also were reliably reduced in CCI rats treated with either 200 or 400 nmol benzamide. Neither dark neurons nor neuropathic pain behaviors were reliably affected by i.t. administration of either 800 nmol novobiocin (a mono(ADP-ribose) synthetase) or 800 nmol benzoic acid (the backbone structure of benzamide), indicating a selective effect of benzamide. Intrathecal treatment with an NO synthase inhibitor NG-nitro-L-arginine methyl ester (40 nmol, but not its inactive D-isomer) utilizing the same benzamide treatment regimen resulted in similar reductions of both dark neurons and neuropathic pain behaviors in CCI rats. These results provide, for the first time, in vivo evidence indicating that benzamide is

  20. GLT1 overexpression reverses established neuropathic pain-related behavior and attenuates chronic dorsal horn neuron activation following cervical spinal cord injury.

    Science.gov (United States)

    Falnikar, Aditi; Hala, Tamara J; Poulsen, David J; Lepore, Angelo C

    2016-03-01

    Development of neuropathic pain occurs in a major portion of traumatic spinal cord injury (SCI) patients, resulting in debilitating and often long-term physical and psychological burdens. Following SCI, chronic dysregulation of extracellular glutamate homeostasis has been shown to play a key role in persistent central hyperexcitability of superficial dorsal horn neurons that mediate pain neurotransmission, leading to various forms of neuropathic pain. Astrocytes express the major CNS glutamate transporter, GLT1, which is responsible for the vast majority of functional glutamate uptake, particularly in the spinal cord. In our unilateral cervical contusion model of mouse SCI that is associated with ipsilateral forepaw heat hypersensitivity (a form of chronic at-level neuropathic pain-related behavior), we previously reported significant and long-lasting reductions in GLT1 expression and functional GLT1-mediated glutamate uptake in cervical spinal cord dorsal horn. To therapeutically address GLT1 dysfunction following cervical contusion SCI, we injected an adeno-associated virus type 8 (AAV8)-Gfa2 vector into the superficial dorsal horn to increase GLT1 expression selectively in astrocytes. Compared to both contusion-only animals and injured mice that received AAV8-eGFP control injection, AAV8-GLT1 delivery increased GLT1 protein expression in astrocytes of the injured cervical spinal cord dorsal horn, resulting in a significant and persistent reversal of already-established heat hypersensitivity. Furthermore, AAV8-GLT1 injection significantly reduced expression of the transcription factor and marker of persistently increased neuronal activation, ΔFosB, in superficial dorsal horn neurons. These results demonstrate that focal restoration of GLT1 expression in the superficial dorsal horn is a promising target for treating chronic neuropathic pain following SCI. © 2015 Wiley Periodicals, Inc.

  1. EFNS guidelines on pharmacological treatment of neuropathic pain

    DEFF Research Database (Denmark)

    Attal, Nadine; Cruccu, G; Haanpää, M

    2006-01-01

    for the efficacy of tricyclic antidepressants, gabapentin, pregabalin and opioids, with a large number of class I trials, followed by topical lidocaine (in PHN) and the newer antidepressants venlafaxine and duloxetine (in PPN). A small number of controlled trials were performed in central pain, trigeminal...

  2. Following the clues to neuropathic pain. Distribution and other leads reveal the cause and the treatment approach.

    Science.gov (United States)

    Belgrade, M J

    1999-11-01

    Neuropathic pain can seem enigmatic at first because it can last indefinitely and often a cause is not evident. However, heightened awareness of typical characteristics, such as the following, makes identification fairly easy: The presence of certain accompanying conditions (e.g., diabetes, HIV or herpes zoster infection, multiple sclerosis) Pain described as shooting, stabbing, lancinating, burning, or searing Pain worse at night Pain following anatomic nerve distribution Pain in a numb or insensate site The presence of allodynia Neuropathic pain responds poorly to standard pain therapies and usually requires specialized medications (e.g., anticonvulsants, tricyclic antidepressants, opioid analgesics) for optimal control. Successful pain control is enhanced with use of a systematic approach consisting of disease modification, local or regional measures, and systemic therapy.

  3. Identification of key genes and pathways associated with neuropathic pain in uninjured dorsal root ganglion by using bioinformatic analysis

    Directory of Open Access Journals (Sweden)

    Chen CJ

    2017-11-01

    Full Text Available Chao-Jin Chen,* De-Zhao Liu,* Wei-Feng Yao, Yu Gu, Fei Huang, Zi-Qing Hei, Xiang Li Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China *These authors contributed equally to this work Purpose: Neuropathic pain is a complex chronic condition occurring post-nervous system damage. The transcriptional reprogramming of injured dorsal root ganglia (DRGs drives neuropathic pain. However, few comparative analyses using high-throughput platforms have investigated uninjured DRG in neuropathic pain, and potential interactions among differentially expressed genes (DEGs and pathways were not taken into consideration. The aim of this study was to identify changes in genes and pathways associated with neuropathic pain in uninjured L4 DRG after L5 spinal nerve ligation (SNL by using bioinformatic analysis.Materials and methods: The microarray profile GSE24982 was downloaded from the Gene Expression Omnibus database to identify DEGs between DRGs in SNL and sham rats. The prioritization for these DEGs was performed using the Toppgene database followed by gene ontology and pathway enrichment analyses. The relationships among DEGs from the protein interactive perspective were analyzed using protein–protein interaction (PPI network and module analysis. Real-time polymerase chain reaction (PCR and Western blotting were used to confirm the expression of DEGs in the rodent neuropathic pain model.Results: A total of 206 DEGs that might play a role in neuropathic pain were identified in L4 DRG, of which 75 were upregulated and 131 were downregulated. The upregulated DEGs were enriched in biological processes related to transcription regulation and molecular functions such as DNA binding, cell cycle, and the FoxO signaling pathway. Ctnnb1 protein had the highest connectivity degrees in the PPI network. The in vivo studies also validated that mRNA and protein levels of Ctnnb1 were

  4. Topical amitriptyline and ketamine for post-herpetic neuralgia and other forms of neuropathic pain.

    Science.gov (United States)

    Sawynok, Jana; Zinger, Celia

    2016-01-01

    Neuropathic pain (NP) has several therapeutic options but efficacy is limited and adverse effects occur, such that additional treatment options are needed. A topical formulation containing amitriptyline 4% and ketamine 2% (AmiKet) may provide such an option. This report summarizes both published and unpublished results of clinical trials with AmiKet. In post-herpetic neuralgia (PHN), AmiKet produces a significant analgesia which is comparable to that produced by oral gabapentin. In diabetic painful neuropathy, AmiKet showed a strong trend towards pain reduction. In mixed neuropathic pain, case series reports suggest a favourable response rate, but are limited by trial characteristics. AmiKet is absorbed minimally following topical administration. Over 700 patients have now received topical AmiKet in clinical regimens, and it is well-tolerated with the adverse effects mainly being application site reactions. Both agents are polymodal, and several mechanisms may contribute to the peripheral efficacy of AmiKet. Topical AmiKet has the potential to be a first-line treatment option for PHN, and to be useful in other NP conditions. Furthermore, AmiKet has the potential to be an adjunct to systemic therapies, with the targeting of a peripheral compartment in addition to central sites of action representing a rational drug combination.

  5. Topical patches as treatments for the management of patient musculoskeletal and neuropathic pain

    Directory of Open Access Journals (Sweden)

    Simona Mirel

    2017-02-01

    Full Text Available The variety and multiple dimensions of pain (acute/chronic, mild/moderate/severe, nociceptive/neuropathic requires different pharmacologic and non-pharmacologic treatments in certain patients. A lot of topical formulation, from various therapeutic classes have been proposed in order to decrease systemic exposure and to reduce the risks of adverse events. Topical as well as transdermal drug delivery systems are proposed as medicated plasters with: anesthetics (lidocaine, analgesic or nonsteroidal anti-inflamatory drugs (NSAIDs, alone or co-formulated. Capsaicin, salicylates, menthol and camphor represent the counterirritant class of topical analgesics used as patch active compounds. These compounds produce their analgesic effect by activating and desensitizing epidermal nociceptors. The most used topical treatment in order to decrease pain is the application of cold and heat patches - by acting directly on the affected tissue. In many cases there is a limited number of studies providing insufficient information to clinicians in order to evaluate the benefits of these products. This paper reviews the use and efficacy of available self-adhesing occlusive medicated plaster (pain patches that might represent an alternative option for the management of patient pain, specially in the case of musculoskeletal and neuropathic disorders.

  6. Progranulin overexpression in sensory neurons attenuates neuropathic pain in mice: Role of autophagy.

    Science.gov (United States)

    Altmann, Christine; Hardt, Stefanie; Fischer, Caroline; Heidler, Juliana; Lim, Hee-Young; Häussler, Annett; Albuquerque, Boris; Zimmer, Béla; Möser, Christine; Behrends, Christian; Koentgen, Frank; Wittig, Ilka; Schmidt, Mirko H H; Clement, Albrecht M; Deller, Thomas; Tegeder, Irmgard

    2016-12-01

    Peripheral or central nerve injury is a frequent cause of chronic pain and the mechanisms are not fully understood. Using newly generated transgenic mice we show that progranulin overexpression in sensory neurons attenuates neuropathic pain after sciatic nerve injury and accelerates nerve healing. A yeast-2-hybrid screen revealed putative interactions of progranulin with autophagy-related proteins, ATG12 and ATG4b. This was supported by colocalization and proteomic studies showing regulations of ATG13 and ATG4b and other members of the autophagy network, lysosomal proteins and proteins involved in endocytosis. The association of progranulin with the autophagic pathway was functionally confirmed in primary sensory neurons. Autophagy and survival were impaired in progranulin-deficient neurons and improved in progranulin overexpressing neurons. Nerve injury in vivo caused an accumulation of LC3b-EGFP positive bodies in neurons of the dorsal root ganglia and nerves suggesting an impairment of autophagic flux. Overexpression of progranulin in these neurons was associated with a reduction of the stress marker ATF3, fewer protein aggregates in the injured nerve and enhanced stump healing. At the behavioral level, further inhibition of the autophagic flux by hydroxychloroquine intensified cold and heat nociception after sciatic nerve injury and offset the pain protection provided by progranulin. We infer that progranulin may assist in removal of protein waste and thereby helps to resolve neuropathic pain after nerve injury. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. The Effect of Repeated Electroacupuncture Analgesia on Neurotrophic and Cytokine Factors in Neuropathic Pain Rats

    Directory of Open Access Journals (Sweden)

    Junying Wang

    2016-01-01

    Full Text Available Chronic pain is a common disability influencing quality of life. Results of previous studies showed that acupuncture has a cumulative analgesic effect, but the relationship with spinal cytokines neurotrophic factors released by astrocytes remains unknown. The present study was designed to observe the effect of electroacupuncture (EA treatment on spinal cytokines neurotrophic factors in chronic neuropathic pain rats. The chronic neuropathic pain was established by chronic constrictive injury (CCI. EA treatment was applied at Zusanli (ST36 and Yanglingquan (GB34 (both bilateral once a day, for 30 min. IL-1β mRNA, TNF-α mRNA, and IL-1 mRNA were detected by quantitative real-time PCR, and the proteins of BDNF, NGF, and NT3/4 were detected by Western blot. The expression levels of cytokines such as IL-1β mRNA, TNF-α mRNA, IL-6 mRNA, and neurotrophic factors such as BDNF, NGF, and NT3/4 in the spinal cord were increased significantly after CCI. The astrocytes released more IL-1β and BDNF after CCI. Repeated EA treatment could suppress the elevated expression of IL-1β mRNA, TNFα mRNA, and BDNF, NGF, and NT3/4 but had no effect on IL-6 mRNA. It is suggested that cytokines and neurotrophic factors which may be closely associated with astrocytes participated in the process of EA relieving chronic pain.

  8. The effect of exercise frequency on neuropathic pain and pain-related cellular reactions in the spinal cord and midbrain in a rat sciatic nerve injury model

    Directory of Open Access Journals (Sweden)

    Sumizono M

    2018-02-01

    Full Text Available Megumi Sumizono,1,2 Harutoshi Sakakima,1 Shotaro Otsuka,1 Takuto Terashi,1 Kazuki Nakanishi,1,2 Koki Ueda,1,2 Seiya Takada,1,2 Kiyoshi Kikuchi3 1Course of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, Kagoshima, Japan; 2Kirishima Orthopedics, Kirishima, Japan; 3Division of Brain Science, Department of Physiology, Kurume University School of Medicine, Kurume, Japan Background: Exercise regimens are established methods that can relieve neuropathic pain. However, the relationship between frequency and intensity of exercise and multiple cellular responses of exercise-induced alleviation of neuropathic pain is still unclear. We examined the influence of exercise frequency on neuropathic pain and the intracellular responses in a sciatic nerve chronic constriction injury (CCI model. Materials and methods: Rats were assigned to four groups as follows: CCI and high-frequency exercise (HFE group, CCI and low-frequency exercise (LFE group, CCI and no exercise (No-Ex group, and naive animals (control group. Rats ran on a treadmill, at a speed of 20 m/min, for 30 min, for 5 (HFE or 3 (LFE days a week, for a total of 5 weeks. The 50% withdrawal threshold was evaluated for mechanical sensitivity. The activation of glial cells (microglia and astrocytes, expression of brain-derived neurotrophic factor (BDNF and μ-opioid receptor in the spinal dorsal horn and endogenous opioid in the midbrain were examined using immunohistochemistry. Opioid receptor antagonists (naloxone were administered using intraperitoneal injection. Results: The development of neuropathic pain was related to the activation of glial cells, increased BDNF expression, and downregulation of the μ-opioid receptor in the ipsilateral spinal dorsal horn. In the No-Ex group, neuropathic pain showed the highest level of mechanical hypersensitivity at 2 weeks, which improved slightly until 5 weeks after CCI. In both exercise groups, the alleviation of

  9. Invasive and non-invasive brain stimulation for treatment of neuropathic pain in patients with spinal cord injury: a review.

    Science.gov (United States)

    Nardone, Raffaele; Höller, Yvonne; Leis, Stefan; Höller, Peter; Thon, Natasha; Thomschewski, Aljoscha; Golaszewski, Stefan; Brigo, Francesco; Trinka, Eugen

    2014-01-01

    Past evidence has shown that invasive and non-invasive brain stimulation may be effective for relieving central pain. To perform a topical review of the literature on brain neurostimulation techniques in patients with chronic neuropathic pain due to traumatic spinal cord injury (SCI) and to assess the current evidence for their therapeutic efficacy. A MEDLINE search was performed using following terms: "Spinal cord injury", "Neuropathic pain", "Brain stimulation", "Deep brain stimulation" (DBS), "Motor cortex stimulation" (MCS), "Transcranial magnetic stimulation" (TMS), "Transcranial direct current stimulation" (tDCS), "Cranial electrotherapy stimulation" (CES). Invasive neurostimulation therapies, in particular DBS and epidural MCS, have shown promise as treatments for neuropathic and phantom limb pain. However, the long-term efficacy of DBS is low, while MCS has a relatively higher potential with lesser complications that DBS. Among the non-invasive techniques, there is accumulating evidence that repetitive TMS can produce analgesic effects in healthy subjects undergoing laboratory-induced pain and in chronic pain conditions of various etiologies, at least partially and transiently. Another very safe technique of non-invasive brain stimulation - tDCS - applied over the sensory-motor cortex has been reported to decrease pain sensation and increase pain threshold in healthy subjects. CES has also proved to be effective in managing some types of pain, including neuropathic pain in subjects with SCI. A number of studies have begun to use non-invasive neuromodulatory techniques therapeutically to relieve neuropathic pain and phantom phenomena in patients with SCI. However, further studies are warranted to corroborate the early findings and confirm different targets and stimulation paradigms. The utility of these protocols in combination with pharmacological approaches should also be explored.

  10. Initial accuracy assessment of the modified S-LANSS for the detection of neuropathic orofacial pain conditions.

    Science.gov (United States)

    Herrero Babiloni, Alberto; Nixdorf, Donald R; Law, Alan S; Moana-Filho, Estephan J; Shueb, Sarah S; Nguyen, Ruby H; Durham, Justin

    2017-01-01

    To evaluate the accuracy of a questionnaire modified for the identification of intraoral pain with neuropathic characteristics in a clinical orofacial pain sample population. 136 participants with at least one of four orofacial pain diagnoses (temporomandibular disorders [TMD, n = 41], acute dental pain [ADP, n = 41], trigeminal neuralgia [TN, n = 19], persistent dentoalveolar pain disorder [PDAP, n = 14]) and a group of pain-free controls (n = 21) completed the modified S-LANSS, a previously adapted version of the original questionnaire devised to detected patients suffering from intraoral pain with neuropathic characteristics. Psychometric properties (sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV]) were calculated in two analyses with two different thresholds: (1) Detection of pain with neuropathic characteristics: PDAP + TN were considered positive, and TMD + ADP + controls were considered negative per gold standard (expert opinion). (2) Detection of PDAP: PDAP was considered positive and TMD + ADP were considered negative per gold standard. For both analyses, target values for adequate sensitivity and specificity were defined as ≥ 80%. For detection of orofacial pain with neuropathic characteristics (PDAP + TN), the modified S-LANSS presented with the most optimistic threshold sensitivity of 52% (95% confidence interval [CI], 34-69), specificity of 70% (95% CI, 60-79), PPV of 35% (95% CI, 22-51), and NPV of 82% (95% CI, 72-89). For detection of PDAP only, with the most optimistic threshold sensitivity was 64% (95% CI, 35-87), specificity 63% (95% CI, 52-74), PPV 23% (95% CI, 11-39) and NPV 91% (95% CI, 81-97). Based on a priori defined criteria, the modified S-LANSS did not show adequate accuracy to detect intraoral pain with neuropathic characteristics in a clinical orofacial pain sample.

  11. Assessment of the clinical relevance of quantitative sensory testing with Von Frey monofilaments in patients with allodynia and neuropathic pain. A pilot study

    OpenAIRE

    Keizer, D.; van Wijhe, M.; Post, W.J.; Uges, D.R.A.; Wierda, J.M.K.H.

    2007-01-01

    Background: Allodynia is a common and disabling symptom in many patients with neuropathic pain. Whereas quantification of pain mostly depends on subjective pain reports, allodynia can also be measured objectively with quantitative sensory testing. In this pilot study, we investigated the clinical relevance of quantitative sensory testing with Von Frey monofilaments in patients with allodynia as a consequence of a neuropathic pain syndrome, by means of correlating subjective pain scores with p...

  12. P2Y12 receptor upregulation in satellite glial cells is involved in neuropathic pain induced by HIV glycoprotein 120 and 2',3'-dideoxycytidine.

    Science.gov (United States)

    Yi, Zhihua; Xie, Lihui; Zhou, Congfa; Yuan, Huilong; Ouyang, Shuai; Fang, Zhi; Zhao, Shanhong; Jia, Tianyu; Zou, Lifang; Wang, Shouyu; Xue, Yun; Wu, Bing; Gao, Yun; Li, Guilin; Liu, Shuangmei; Xu, Hong; Xu, Changshui; Zhang, Chunping; Liang, Shangdong

    2018-03-01

    The direct neurotoxicity of HIV and neurotoxicity of combination antiretroviral therapy medications both contribute to the development of neuropathic pain. Activation of satellite glial cells (SGCs) in the dorsal root ganglia (DRG) plays a crucial role in mechanical and thermal hyperalgesia. The P2Y 12 receptor expressed in SGCs of the DRG is involved in pain transmission. In this study, we explored the role of the P2Y 12 receptor in neuropathic pain induced by HIV envelope glycoprotein 120 (gp120) combined with ddC (2',3'-dideoxycytidine). A rat model of gp120+ddC-induced neuropathic pain was used. Peripheral nerve exposure to HIV-gp120+ddC increased mechanical and thermal hyperalgesia in gp120+ddC-treated model rats. The gp120+ddC treatment increased expression of P2Y 12 receptor mRNA and protein in DRG SGCs. In primary cultured DRG SGCs treated with gp120+ddC, the levels of [Ca 2+ ] i activated by the P2Y 12 receptor agonist 2-(Methylthio) adenosine 5'-diphosphate trisodium salt (2-MeSADP) were significantly increased. P2Y 12 receptor shRNA treatment inhibited 2-MeSADP-induced [Ca 2+ ] i in primary cultured DRG SGCs treated with gp120+ddC. Intrathecal treatment with a shRNA against P2Y 12 receptor in DRG SGCs reduced the release of pro-inflammatory cytokines, decreased phosphorylation of p38 MAPK in the DRG of gp120+ddC-treated rats. Thus, downregulating the P2Y 12 receptor relieved mechanical and thermal hyperalgesia in gp120+ddC-treated rats.

  13. Transcranial direct current stimulation to lessen neuropathic pain after spinal cord injury: a mechanistic PET study.

    Science.gov (United States)

    Yoon, Eun Jin; Kim, Yu Kyeong; Kim, Hye-Ri; Kim, Sang Eun; Lee, Youngjo; Shin, Hyung Ik

    2014-01-01

    It is suggested that transcranial direct current stimulation (tDCS) can produce lasting changes in corticospinal excitability and can potentially be used for the treatment of neuropathic pain. However, the detailed mechanisms underlying the effects of tDCS are unknown. We investigated the underlying neural mechanisms of tDCS for chronic pain relief using [(18)F]-fluorodeoxyglucose positron emission tomography ([(18)F]FDG-PET). Sixteen patients with neuropathic pain (mean age 44.1 ± 8.6 years, 4 females) due to traumatic spinal cord injury received sham or active anodal stimulation of the motor cortex using tDCS for 10 days (20 minutes, 2 mA, twice a day). The effect of tDCS on regional cerebral glucose metabolism was evaluated by [(18)F]FDG-PET before and after tDCS sessions. There was a significant decrease in the numeric rating scale scores for pain, from 7.6 ± 0.5 at baseline to 5.9 ± 1.8 after active tDCS (P = .016). We found increased metabolism in the medulla and decreased metabolism in the left dorsolateral prefrontal cortex after active tDCS treatment compared with the changes induced by sham tDCS. Additionally, an increase in metabolism after active tDCS was observed in the subgenual anterior cingulate cortex and insula. The results of this study suggest that anodal stimulation of the motor cortex using tDCS can modulate emotional and cognitive components of pain and normalize excessive attention to pain and pain-related information.

  14. A review of the clinical utility of duloxetine in the treatment of diabetic peripheral neuropathic pain

    Directory of Open Access Journals (Sweden)

    King JB

    2015-08-01

    Full Text Available Jordan B King, Marisa B Schauerhamer, Brandon K Bellows Pharmacotherapy Outcomes Research Center, University of Utah College of Pharmacy, Salt Lake City, UT, USA Abstract: Diabetes mellitus is a world-wide epidemic with many long-term complications, with neuropathy being the most common. In particular, diabetic peripheral neuropathic pain (DPNP, can be one of the most distressing complications associated with diabetes, leading to decreases in physical and mental quality of life. Despite the availability of many efficient medications, DPNP remains a challenge to treat, and the optimal sequencing of pharmacotherapy remains unknown. Currently, there are only three medications approved by the US Food and Drug Administration specifically for the management of DPNP. Duloxetine (DUL, a selective serotonin-norepinephrine reuptake inhibitor, is one of these. With the goal of optimizing pharmacotherapy use in DPNP population, a review of current literature was conducted, and the clinical utility of DUL described. Along with early clinical trials, recently published observational studies and pharmacoeconomic models may be useful in guiding decision making by clinicians and managed care organizations. In real-world practice settings, DUL is associated with decreased or similar opioid utilization, increased medication adherence, and similar health care costs compared with current standard of care. DUL has consistently been found to be a cost-effective option over short time-horizons. Currently, the long-term cost-effectiveness of DUL is unknown. Evidence derived from randomized clinical trials, real-world observations, and economic models support the use of DUL as a first-line treatment option from the perspective of the patient, clinician, and managed care payer. Keywords: clinical trials, pharmacoeconomic studies, opioid-utilization, health care utilization, pregabalin, tricyclic antidepressants, gabapentin

  15. Duloxetine compliance and its association with healthcare costs among patients with diabetic peripheral neuropathic pain.

    Science.gov (United States)

    Wu, N; Chen, S; Boulanger, L; Fraser, K; Bledsoe, S L; Zhao, Y

    2009-09-01

    Duloxetine is approved to treat diabetic peripheral neuropathic pain (DPNP) in the US. The study objective was to examine the predictors of duloxetine compliance, and its association with healthcare costs among DPNP patients. The study used administrative claims databases to identify non-depressed DPNP patients with a duloxetine prescription dispensed between October 1, 2004 and December 31, 2006. Two cohorts of patients were constructed based on compliance to duloxetine therapy over 1-year follow-up with high compliance defined as a medication possession ratio (MPR) > or =0.80. All-cause, diabetes-, and DPNP-related healthcare costs during 1-year follow-up were estimated. Logistic regressions were performed to examine how average daily dose (ADD) of duloxetine and other factors may influence compliance. Multivariate regressions were estimated to examine the association between compliance and healthcare costs. The study included 1,380 commercially insured (mean age 55 years) and 974 patients with employer-sponsored Medicare supplemental insurance (mean age 75 years). In both populations, patients with an ADD >30 mg were more likely to be compliant with the therapy compared with those with an ADD of compliance patients had greater all-cause ($5,334, pcosts ($3,414, pcompliance patients, with the biggest difference from inpatient costs (all-cause: $7,508; diabetes-related: $3,785, all pcosts were not significant. DPNP patients with a higher ADD of duloxetine over a 1-year follow-up period were more compliant with the therapy. Duloxetine patients with high compliance were also associated with lower healthcare costs. Due to the use of a retrospective cohort design on administrative claims database, limitations of this analysis include a lack of formal diagnostic testing of patients, and inability to infer causality or measure factors such as DPNP severity that are not captured in such database.

  16. The Evaluation of the Effect of Neuropathic Pain on Functional Disability in Patients with Chronic Low Back Pain

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    Yalkın Çalık

    2015-12-01

    Full Text Available Objective: The aim of this study was to evaluate both the prevalence of neuropathic pain (NP and the effect of functional disability of NP in patients with chronic low back pain (CLBP. Materials and Methods: In this study, outpatients data were reviewed retrospectively from January 2014 to December 2014 to determine the patients with CLBP. 190 patients with CLBP meeting the inclusion criteria were included. NP scores of the patients were assessed using Leeds Assessment of Neuropathic Symptoms and Signs (LANSS and the evaluation of pain was performed using the Visual analoque scale (VAS and functional disability scores was determined by the Oswestry disability index (ODI. Results: In this study NP was detected in 39.4% of the patients with CLBP. The number of female patients with NP (n=60, %80 was significantly higher than the number of male patients with NP (n=15, %20, (p<0.05. ODI and VAS scores of the patients with NP [(19.81±7.28, (5.08±0.76] was significantly higher than those of the patients without NP [(15.28±6.83, (4.44±1.14], (p<0,001. Conclusion: It was found that the co-existence of NP with CLBP increases pain and functional disability.

  17. High-Frequency Stimulation of Dorsal Column Axons: Potential Underlying Mechanism of Paresthesia-Free Neuropathic Pain Relief.

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    Arle, Jeffrey E; Mei, Longzhi; Carlson, Kristen W; Shils, Jay L

    2016-06-01

    Spinal cord stimulation (SCS) treats neuropathic pain through retrograde stimulation of dorsal column axons and their inhibitory effects on wide dynamic range (WDR) neurons. Typical SCS uses frequencies from 50-100 Hz. Newer stimulation paradigms use high-frequency stimulation (HFS) up to 10 kHz and produce pain relief but without paresthesia. Our hypothesis is that HFS preferentially blocks larger diameter axons (12-15 µm) based on dynamics of ion channel gates and the electric potential gradient seen along the axon, resulting in inhibition of WDR cells without paresthesia. We input field potential values from a finite element model of SCS into an active axon model with ion channel subcomponents for fiber diameters 1-20 µm and simulated dynamics on a 0.001 msec time scale. Assuming some degree of wave rectification seen at the axon, action potential (AP) blockade occurs as hypothesized, preferentially in larger over smaller diameters with blockade in most medium and large diameters occurring between 4.5 and 10 kHz. Simulations show both ion channel gate and virtual anode dynamics are necessary. At clinical HFS frequencies and pulse widths, HFS preferentially blocks larger-diameter fibers and concomitantly recruits medium and smaller fibers. These effects are a result of interaction between ion gate dynamics and the "activating function" (AF) deriving from current distribution over the axon. The larger fibers that cause paresthesia in low-frequency simulation are blocked, while medium and smaller fibers are recruited, leading to paresthesia-free neuropathic pain relief by inhibiting WDR cells. © 2016 International Neuromodulation Society.

  18. Perineural pretreatment of bee venom attenuated the development of allodynia in the spinal nerve ligation injured neuropathic pain model; an experimental study.

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    Koh, Won Uk; Choi, Seong Soo; Lee, Jong Hyuk; Lee, So Hee; Lee, Sun Kyung; Lee, Yoon Kyung; Leem, Jeong Gil; Song, Jun Gol; Shin, Jin Woo

    2014-11-04

    Diluted bee venom (BV) is known to have anti-nociceptive and anti-inflammatory effects. We therefore assessed whether perineural bee venom pretreatment could attenuate the development of neuropathic pain in the spinal nerve ligation injured animal model. Neuropathic pain was surgically induced in 30 male Sprague Dawley rats by ligation of the L5 and L6 spinal nerves, with 10 rats each treated with saline and 0.05 and 0.1 mg BV. Behavioral testing for mechanical, cold, and thermal allodynia was conducted on postoperative days 3 to 29. Three rats in each group and 9 sham operated rats were sacrificed on day 9, and the expression of transient receptor potential vanilloid type 1 (TRPV1), ankyrin type 1 (TRPA1), and melastatin type 8 (TRPM8) receptors in the ipsilateral L5 dorsal root ganglion was analyzed. The perineural administration of BV to the spinal nerves attenuated the development of mechanical, thermal, and cold allodynia, and the BV pretreatment reduced the expression of TRPV1, TRPA1, TRPM8 and c - Fos in the ipsilateral dorsal root ganglion. The current study demonstrates that the perineural pretreatment with diluted bee venom before the induction of spinal nerve ligation significantly suppresses the development of neuropathic pain. Furthermore, this bee venom induced suppression was strongly related with the involvement of transient receptor potential family members.

  19. A Multiplex Protein Panel Applied to Cerebrospinal Fluid Reveals Three New Biomarker Candidates in ALS but None in Neuropathic Pain Patients.

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    Anne-Li Lind

    Full Text Available The objective of this study was to develop and apply a novel multiplex panel of solid-phase proximity ligation assays (SP-PLA requiring only 20 μL of samples, as a tool for discovering protein biomarkers for neurological disease and treatment thereof in cerebrospinal fluid (CSF. We applied the SP-PLA to samples from two sets of patients with poorly understood nervous system pathologies amyotrophic lateral sclerosis (ALS and neuropathic pain, where patients were treated with spinal cord stimulation (SCS. Forty-seven inflammatory and neurotrophic proteins were measured in samples from 20 ALS patients and 15 neuropathic pain patients, and compared to normal concentrations in CSF from control individuals. Nineteen of the 47 proteins were detectable in more than 95% of the 72 controls. None of the 21 proteins detectable in CSF from neuropathic pain patients were significantly altered by SCS. The levels of the three proteins, follistatin, interleukin-1 alpha, and kallikrein-5 were all significantly reduced in the ALS group compared to age-matched controls. These results demonstrate the utility of purpose designed multiplex SP-PLA panels in CSF biomarker research for understanding neuropathological and neurotherapeutic mechanisms. The protein changes found in the CSF of ALS patients may be of diagnostic interest.

  20. Andrographolide Inhibits Mechanical and Thermal Hyperalgesia in a Rat Model of HIV-Induced Neuropathic Pain

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    Zhihua Yi

    2018-06-01

    Full Text Available Aim: In this study, we investigated whether andrographolide (Andro can alleviate neuropathic pain induced by HIV gp120 plus ddC treatment and the mechanism of its action.Methods: The paw withdrawal threshold and the paw withdrawal latency were observed to assess pain behaviors in all groups of the rats, including control group, control combined with Andro treatment group, sham group, gp120 combined with ddC treatment group, gp120 plus ddC combined with A438079 treatment group, and gp120 plus ddC combined with Andro treatment by intrathecally injecting at a dose of 25 μg/20 μl group. The protein expression levels of the P2X7 receptor, tumor necrosis factor-α-receptor (TNFα-R, interleukin-1β (IL-1β, IL-10, phospho-extracellular regulated protein kinases (ERK (p-ERK in the L4–L6 dorsal root ganglia (DRG were measured by western blotting. Real-time quantitative polymerase chain reaction was used to test the mRNA expression level of the P2X7 receptor. Double-labeling immunofluorescence was used to identify the co-localization of the P2X7 receptor with glial fibrillary acidic protein (GFAP in DRG. Molecular docking was performed to identify whether the Andro interacted perfectly with the rat P2X7 (rP2X7 receptor.Results: Andro attenuated the mechanical and thermal hyperalgesia in gp120+ddC-treated rats and down-regulated the P2X7 receptor mRNA and protein expression in the L4–L6 DRGs of gp120+ddC-treated rats. Additionally, Andro simultaneously decreased the expression of TNFα-R and IL-1β protein, increased the expression of IL-10 protein in L4–L6 DRGs, and inhibited the activation of ERK signaling pathways. Moreover, Andro decreased the co-expression of GFAP and the P2X7 receptor in the SGCs of L4–L6 DRG on 14th day after surgery.Conclusion: Andro decreased the hyperalgesia induced by gp120 plus ddC.

  1. MiR-19a targets suppressor of cytokine signaling 1 to modulate the progression of neuropathic pain.

    Science.gov (United States)

    Wang, Conghui; Jiang, Qi; Wang, Min; Li, Dong

    2015-01-01

    We aimed to investigate whether miR-19a is associated with neuropathic pain and elucidate the underlying regulatory mechanism. We established a neuropathic pain model of bilateral chronic constriction injury (bCCI). Then bCCI rats were injected with mo-miR-19a, siR-SOCS1 or blank expression vector through a microinjection syringe via an intrathecal catheter on 3 day before surgery and after surgery. Behavioral tests, such as mechanical allodynia, thermal hyperalgesia and acetone induced cold allodynia, were performed to evaluate the pain threshold. Besides, quantitative real-time polymerase chain reaction (qRT-PCR) was performed to determine the expression of miR-19a and western blotting was carried out to measure the expression of SOCS1. miR-19a expression levels were markedly increased in neuropathic pain models. Moreover, miR-19a significantly attenuated mechanical allodynia and thermal hyperalgesia, and similar results were obtained after knockdown of SOCS1 expression. However, miR-19a markedly increased the times that the rats appeared a sign of cold allodynia, and knockdown of SOCS1 expression had similar effects. Besides, the results of bioinformatics analysis and western blotting analysis were all confirmed that SOCS1 was a direct target of miR-19a in neuropathic pain models. Our finding indicate that SOCS1 is a direct target of miR-19a in neuropathic pain rats and miR-19a may play a critical role in regulating of neuropathic pain via targeting SOCS1.

  2. JNK-induced MCP-1 production in spinal cord astrocytes contributes to central sensitization and neuropathic pain.

    Science.gov (United States)

    Gao, Yong-Jing; Zhang, Ling; Samad, Omar Abdel; Suter, Marc R; Yasuhiko, Kawasaki; Xu, Zhen-Zhong; Park, Jong-Yeon; Lind, Anne-Li; Ma, Qiufu; Ji, Ru-Rong

    2009-04-01

    Our previous study showed that activation of c-jun-N-terminal kinase (JNK) in spinal astrocytes plays an important role in neuropathic pain sensitization. We further investigated how JNK regulates neuropathic pain. In cultured astrocytes, tumor necrosis factor alpha (TNF-alpha) transiently activated JNK via TNF receptor-1. Cytokine array indicated that the chemokine CCL2/MCP-1 (monocyte chemoattractant protein-1) was strongly induced by the TNF-alpha/JNK pathway. MCP-1 upregulation by TNF-alpha was dose dependently inhibited by the JNK inhibitors SP600125 (anthra[1,9-cd]pyrazol-6(2H)-one) and D-JNKI-1. Spinal injection of TNF-alpha produced JNK-dependent pain hypersensitivity and MCP-1 upregulation in the spinal cord. Furthermore, spinal nerve ligation (SNL) induced persistent neuropathic pain and MCP-1 upregulation in the spinal cord, and both were suppressed by D-JNKI-1. Remarkably, MCP-1 was primarily induced in spinal cord astrocytes after SNL. Spinal administration of MCP-1 neutralizing antibody attenuated neuropathic pain. Conversely, spinal application of MCP-1 induced heat hyperalgesia and phosphorylation of extracellular signal-regulated kinase in superficial spinal cord dorsal horn neurons, indicative of central sensitization (hyperactivity of dorsal horn neurons). Patch-clamp recordings in lamina II neurons of isolated spinal cord slices showed that MCP-1 not only enhanced spontaneous EPSCs but also potentiated NMDA- and AMPA-induced currents. Finally, the MCP-1 receptor CCR2 was expressed in neurons and some non-neuronal cells in the spinal cord. Together, we have revealed a previously unknown mechanism of MCP-1 induction and action. MCP-1 induction in astrocytes after JNK activation contributes to central sensitization and neuropathic pain facilitation by enhancing excitatory synaptic transmission. Inhibition of the JNK/MCP-1 pathway may provide a new therapy for neuropathic pain management.

  3. The major brain endocannabinoid 2-AG controls neuropathic pain and mechanical hyperalgesia in patients with neuromyelitis optica.

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    Hannah L Pellkofer

    Full Text Available Recurrent myelitis is one of the predominant characteristics in patients with neuromyelitis optica (NMO. While paresis, visual loss, sensory deficits, and bladder dysfunction are well known symptoms in NMO patients, pain has been recognized only recently as another key symptom of the disease. Although spinal cord inflammation is a defining aspect of neuromyelitis, there is an almost complete lack of data on altered somatosensory function, including pain. Therefore, eleven consecutive patients with NMO were investigated regarding the presence and clinical characteristics of pain. All patients were examined clinically as well as by Quantitative Sensory Testing (QST following the protocol of the German Research Network on Neuropathic Pain (DFNS. Additionally, plasma endocannabinoid levels and signs of chronic stress and depression were determined. Almost all patients (10/11 suffered from NMO-associated neuropathic pain for the last three months, and 8 out of 11 patients indicated relevant pain at the time of examination. Symptoms of neuropathic pain were reported in the vast majority of patients with NMO. Psychological testing revealed signs of marked depression. Compared to age and gender-matched healthy controls, QST revealed pronounced mechanical and thermal sensory loss, strongly correlated to ongoing pain suggesting the presence of deafferentation-induced neuropathic pain. Thermal hyperalgesia correlated to MRI-verified signs of spinal cord lesion. Heat hyperalgesia was highly correlated to the time since last relapse of NMO. Patients with NMO exhibited significant mechanical and thermal dysesthesia, namely dynamic mechanical allodynia and paradoxical heat sensation. Moreover, they presented frequently with either abnormal mechanical hypoalgesia or hyperalgesia, which depended significantly on plasma levels of the endogenous cannabinoid 2-arachidonoylglycerole (2-AG. These data emphasize the high prevalence of neuropathic pain and hyperalgesia

  4. Can gradual dose titration of ketamine for management of neuropathic pain prevent psychotomimetic effects in patients with advanced cancer?

    Science.gov (United States)

    Okamoto, Yoshiaki; Tsuneto, Satoru; Tanimukai, Hitoshi; Matsuda, Yoichi; Ohno, Yumiko; Tsugane, Mamiko; Uejima, Etsuko

    2013-08-01

    Ketamine is often used to manage neuropathic pain in patients with cancer. However, it occasionally causes psychotomimetic effects such as vivid dreams, nightmares, illusions, hallucinations, and altered body image. To examine whether gradual dose titration of ketamine for management of neuropathic pain prevents psychotomimetic effects in patients with advanced cancer. This was a retrospective chart review. We administered ketamine when neuropathic pain in patients with advanced cancer became refractory to opioids and oral adjuvant analgesics. The starting dose of ketamine was 10 mg/d by continuous intravenous infusion. The dose was gradually increased by 10 mg/d every 4 to 6 hours to 50 mg/d or until the pain was relieved. It was subsequently increased by 25 mg/d every 12 to 24 hours until the pain was relieved. For this study, we enrolled 46 patients with advanced cancer. The mean age was 52.2 ± 16.9 years. The mean dose at onset of action and maximum dose of ketamine were 56 ± 58 and 272 ± 214 mg/d, respectively. The mean pain intensity (numerical rating scale) decreased significantly from 7.3 ± 2.0 to 3.5 ± 2.2 after the administration of ketamine (P ketamine for management of neuropathic pain can prevent psychotomimetic effects in patients with advanced cancer.

  5. Experienced dilemmas of everyday life in chronic neuropathic pain patients--results from a critical incident study.

    Science.gov (United States)

    Hensing, Gunnel K E; Sverker, Annette M; Leijon, Göran S

    2007-06-01

    Neuropathic pain is a disabling chronic condition with limited therapeutic options. Few studies have addressed patient's experience and strategies. The aim of this study was to explore dilemmas experienced in order to improve care and rehabilitation. An interview study with 39 patients suffering from neuropathic pain of different origin was performed. We used the critical incident technique to collect data. Questions on occasions when patients had been hindered by or reminded of their neuropathic pain were included, and the self-perceived consequences and management of such occasions. The interviews were transcribed verbatim and analysed qualitatively. A broad range of experiences categorised into dilemmas, disturbances, consequences and managements from most parts of everyday life was identified. The dilemmas were 'housework', 'sitting', 'physical activity', 'personal hygiene', 'sleeping difficulties', 'hypersensitivity to external stimuli', 'social relationships', 'transportation' and 'leisure time'. Disturbances were 'failures', 'inabilities' and 'restrictions'. Consequences were 'increased pain', 'psychological reactions' and 'physical symptoms'. The majority of the patients used activity-oriented strategies to manage their pain such as alternative ways of performing the task, a cognitive approach or simply ignoring the pain. This is one of the first studies presenting detailed data on everyday dilemmas, disturbances and consequences of patients with chronic neuropathic pain. Such information is important in clinical settings to improve care and rehabilitation.

  6. The contribution of TRPM8 and TRPA1 channels to cold allodynia and neuropathic pain.

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    Ombretta Caspani

    Full Text Available Cold allodynia is a common feature of neuropathic pain however the underlying mechanisms of this enhanced sensitivity to cold are not known. Recently the transient receptor potential (TRP channels TRPM8 and TRPA1 have been identified and proposed to be molecular sensors for cold. Here we have investigated the expression of TRPM8 and TRPA1 mRNA in the dorsal root ganglia (DRG and examined the cold sensitivity of peripheral sensory neurons in the chronic construction injury (CCI model of neuropathic pain in mice.In behavioral experiments, chronic constriction injury (CCI of the sciatic nerve induced a hypersensitivity to both cold and the TRPM8 agonist menthol that developed 2 days post injury and remained stable for at least 2 weeks. Using quantitative RT-PCR and in situ hybridization we examined the expression of TRPM8 and TRPA1 in DRG. Both channels displayed significantly reduced expression levels after injury with no change in their distribution pattern in identified neuronal subpopulations. Furthermore, in calcium imaging experiments, we detected no alterations in the number of cold or menthol responsive neurons in the DRG, or in the functional properties of cold transduction following injury. Intriguingly however, responses to the TRPA1 agonist mustard oil were strongly reduced.Our results indicate that injured sensory neurons do not develop abnormal cold sensitivity after chronic constriction injury and that alterations in the expression of TRPM8 and TRPA1 are unlikely to contribute directly to the pathogenesis of cold allodynia in this neuropathic pain model.

  7. APP overexpression prevents neuropathic pain and motoneuron death after peripheral nerve injury in mice.

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    Kotulska, Katarzyna; Larysz-Brysz, Magdalena; LePecheur, Marie; Marcol, Wiesław; Lewin-Kowalik, Joanna; Paly, Evelyn; London, Jacqueline

    2010-03-16

    Despite general capacity of peripheral nervous system to regenerate, peripheral nerve injury is often followed by incomplete recovery of function and sometimes burdened by neuropathic pain. Amyloid precursor protein (APP) was suggested to play a role in neuronal growth, however, its role in peripheral nerve repair was not studied. The aim of this study was to examine the role of APP overexpression in peripheral nerve regeneration and neuropathic pain-related behavior in mice. Sciatic nerves of APP overexpressing and FVB/N wild-type mice were transected and immediately resutured. Evaluation of motor and sensory function and autotomy was carried out during 4-week follow up. We found no autotomy behavior as well as less significant atrophy of denervated muscles in APP overexpressing animals when compared to wild-type ones. Sciatic nerve function index outcome did not differ between groups. Histological evaluation revealed that the intensity of regeneration features, including GAP-43-positive growth cones and Schwann cells number in the distal stump of the transected nerve, was also similar in both groups. However, the regenerating fibers were organized more chaotically in wild-type mice and neuromas were much more often seen in this group. The number of macrophages infiltrating the injury site was significantly higher in control group. The number of surviving motoneurons was higher in transgenic mice than in control animals. Taken together, our findings suggest that APP overexpression is beneficial for nerve regeneration processes due to better organization of regenerating fibers, increased survival of motoneurons after autotomy and prevention of neuropathic pain. Copyright 2009 Elsevier Inc. All rights reserved.

  8. Spinal cord stimulation attenuates temporal summation in patients with neuropathic pain.

    Science.gov (United States)

    Eisenberg, Elon; Burstein, Yulia; Suzan, Erica; Treister, Roi; Aviram, Joshua

    2015-03-01

    Evidence has shown that electrical stimulation at the dorsal columns attenuated the "wind-up" phenomenon in dorsal horn neurons in nerve-injured rats. This study was aimed to test the effect of spinal cord stimulation (SCS) on temporal summation (TS), the clinical correlate of the wind-up phenomenon in patients with radicular leg pain. Eighteen patients with SCS implants were tested both 30 minutes after SCS activation ("ON") and 2 hours after turning it off ("OFF"), in a random order. Temporal summation was evaluated in the most painful site in the affected leg and in the corresponding area in the contralateral leg by applying a tonic painful heat stimulus (46.5°C; 120 seconds) and simultaneous recording of the perceived heat pain intensity. Patients were also requested to report their clinical pain intensity (0-100 numerical pain scale) during SCS "ON" and "OFF". The Wilcoxon signed rank test was used in the comparisons between SCS "ON" and "OFF". Spinal cord stimulation activation significantly attenuated clinical pain intensity (from 66 ± 18 to 27 ± 31, P spinal cord neurons, is a possible mechanism underlying SCS analgesia in patients with neuropathic pain.

  9. Neuron-Derived ADAM10 Production Stimulates Peripheral Nerve Injury-Induced Neuropathic Pain by Cleavage of E-Cadherin in Satellite Glial Cells.

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    Li, Jian; Ouyang, Qing; Chen, Cheng-Wen; Chen, Qian-Bo; Li, Xiang-Nan; Xiang, Zheng-Hua; Yuan, Hong-Bin

    2017-09-01

    Increasing evidence suggests the potential involvement of metalloproteinase family proteins in the pathogenesis of neuropathic pain, although the underlying mechanisms remain elusive. Using the spinal nerve ligation model, we investigated whether ADAM10 proteins participate in pain regulation. By implementing invitro methods, we produced a purified culture of satellite glial cells to study the underlying mechanisms of ADAM10 in regulating neuropathic pain. Results showed that the ADAM10 protein was expressed in calcitonin gene-related peptide (CGRP)-containing neurons of the dorsal root ganglia, and expression was upregulated following spinal nerve ligation surgery invivo. Intrathecal administration of GI254023X, an ADAM10 selective inhibitor, to the rats one to three days after spinal nerve ligation surgery attenuated the spinal nerve ligation-induced mechanical allodynia and thermal hyperalgesia. Intrathecal injection of ADAM10 recombinant protein simulated pain behavior in normal rats to a similar extent as those treated by spinal nerve ligation surgery. These results raised a question about the relative contribution of ADAM10 in pain regulation. Further results showed that ADAM10 might act by cleaving E-cadherin, which is mainly expressed in satellite glial cells. GI254023X reversed spinal nerve ligation-induced downregulation of E-cadherin and activation of cyclooxygenase 2 after spinal nerve ligation. β-catenin, which creates a complex with E-cadherin in the membranes of satellite glial cells, was also downregulated by spinal nerve ligation surgery in satellite glial cells. Finally, knockdown expression of β-catenin by lentiviral infection in purified satellite glial cells increased expression of inducible nitric oxide synthase and cyclooxygenase 2. Our findings indicate that neuron-derived ADAM10 production stimulates peripheral nerve injury-induced neuropathic pain by cleaving E-cadherin in satellite glial cells. © 2017 American Academy of Pain Medicine

  10. Pulsed magnetic field enhances therapeutic efficiency of mesenchymal stem cells in chronic neuropathic pain model.

    Science.gov (United States)

    Mert, Tufan; Kurt, Akif Hakan; Altun, İdiris; Celik, Ahmet; Baran, Furkan; Gunay, Ismail

    2017-05-01

    Cell-based or magnetic field therapies as alternative approaches to pain management have been tested in several experimental pain models. The aim of this study therefore was to investigate the actions of the cell-based therapy (adipose tissue derived mesenchymal stem cells; ADMSC) or pulsed magnetic field (PMF) therapy and magneto-cell therapy (combination of ADMSC and PMF) in chronic constriction nerve injury model (CCI). The actions of individual ADMSC (route dependent [systemic or local], time-dependent [a day or a week after surgery]), or PMF and their combination (magneto-cell) therapies on hyperalgesia and allodynia were investigated by using thermal plantar test and a dynamic plantar aesthesiometer, respectively. In addition, various cytokine levels (IL-1β, IL-6, and IL-10) of rat sciatic nerve after CCI were analyzed. Following the CCI, both latency and threshold significantly decreased. ADMSC or PMF significantly increased latencies and thresholds. The combination of ADMSC with PMF even more significantly increased latency and threshold when compared with ADMSC alone. However, ADMSC-induced decrease in pro-inflammatory or increase in anti-inflammatory cytokines levels were partially prevented by PMF treatments. Present findings may suggest that both cell-based and magnetic therapies can effectively attenuate chronic neuropathic pain symptoms. Combined magneto-cell therapy may also efficiently reverse neuropathic signs. Bioelectromagnetics. 38:255-264, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  11. Peripheral nerve stimulation (PNS) in the trapezius muscle region alleviate chronic neuropathic pain after lower brachial plexus root avulsion lesion: A case report

    DEFF Research Database (Denmark)

    Sørensen, Jens Christian Hedemann; Meier, Kaare; Perinpam, Larshan

    Peripheral nerve stimulation (PNS) in the trapezius muscle region alleviate chronic neuropathic pain after lower brachial plexus root avulsion lesion: A case report......Peripheral nerve stimulation (PNS) in the trapezius muscle region alleviate chronic neuropathic pain after lower brachial plexus root avulsion lesion: A case report...

  12. Update on neuropathic pain treatment for trigeminal neuralgia

    Science.gov (United States)

    Al-Quliti, Khalid W.

    2015-01-01

    Trigeminal neuralgia is a syndrome of unilateral, paroxysmal, stabbing facial pain, originating from the trigeminal nerve. Careful history of typical symptoms is crucial for diagnosis. Most cases are caused by vascular compression of the trigeminal root adjacent to the pons leading to focal demyelination and ephaptic axonal transmission. Brain imaging is required to exclude secondary causes. Many medical and surgical treatments are available. Most patients respond well to pharmacotherapy; carbamazepine and oxcarbazepine are first line therapy, while lamotrigine and baclofen are considered second line treatments. Other drugs such as topiramate, levetiracetam, gabapentin, pregabalin, and botulinum toxin-A are alternative treatments. Surgical options are available if medications are no longer effective or tolerated. Microvascular decompression, gamma knife radiosurgery, and percutaneous rhizotomies are most promising surgical alternatives. This paper reviews the medical and surgical therapeutic options for the treatment of trigeminal neuralgia, based on available evidence and guidelines. PMID:25864062

  13. Cannabinoids and centrak neuropathic pain. A review (Cannabinoidi e dolore neuropatico centrale. Una rassegna

    Directory of Open Access Journals (Sweden)

    Francesco Crestani

    2014-03-01

    Full Text Available Only recently, the medical community highlighted the pharmacological scientific bases of the effects of Cannabis. The most important active principle, Delta-9-tetrahydrocannabinol was identified in the second half of the last century, and receptors were subsequently identified and endogenous ligands, called endocannabinoids, were characterized. The effectiveness of the cannabinoids in the treatment of nausea and vomit due to anti-neoplastic chemotherapy and in the wasting-syndrome during AIDS is recognized. Moreover, the cannabinoids have shown analgesic properties, particularly interesting with regard to the central neuropathic pain. This article will review the current knowledge and will give practical guidance on how to proceed in prescribing cannabinoids.

  14. Evaluation of Lercanidipine in Paclitaxel-Induced Neuropathic Pain Model in Rat: A Preliminary Study

    OpenAIRE

    Saha, Lekha; Hota, Debasish; Chakrabarti, Amitava

    2012-01-01

    Objective. To demonstrate the antinociceptive effect of lercanidipine in paclitaxel-induced neuropathy model in rat. Materials and Methods. A total of 30 rats were divided into five groups of six rats in each group as follows: Gr I: 0.9% NaCl, Gr II: paclitaxel + 0.9% NaCl, Gr III: paclitaxel + lercanidipine 0.5 μg/kg, Gr IV: paclitaxel + lercanidipine 1 μg/kg, and Gr V: paclitaxel + lercanidipine 2.5 μg/kg. Paclitaxel-induced neuropathic pain in rat was produced by single intraperitoneal (i....

  15. Dynamic Neural State Identification in Deep Brain Local Field Potentials of Neuropathic Pain.

    Science.gov (United States)

    Luo, Huichun; Huang, Yongzhi; Du, Xueying; Zhang, Yunpeng; Green, Alexander L; Aziz, Tipu Z; Wang, Shouyan

    2018-01-01

    In neuropathic pain, the neurophysiological and neuropathological function of the ventro-posterolateral nucleus of the thalamus (VPL) and the periventricular gray/periaqueductal gray area (PVAG) involves multiple frequency oscillations. Moreover, oscillations related to pain perception and modulation change dynamically over time. Fluctuations in these neural oscillations reflect the dynamic neural states of the nucleus. In this study, an approach to classifying the synchronization level was developed to dynamically identify the neural states. An oscillation extraction model based on windowed wavelet packet transform was designed to characterize the activity level of oscillations. The wavelet packet coefficients sparsely represented the activity level of theta and alpha oscillations in local field potentials (LFPs). Then, a state discrimination model was designed to calculate an adaptive threshold to determine the activity level of oscillations. Finally, the neural state was represented by the activity levels of both theta and alpha oscillations. The relationship between neural states and pain relief was further evaluated. The performance of the state identification approach achieved sensitivity and specificity beyond 80% in simulation signals. Neural states of the PVAG and VPL were dynamically identified from LFPs of neuropathic pain patients. The occurrence of neural states based on theta and alpha oscillations were correlated to the degree of pain relief by deep brain stimulation. In the PVAG LFPs, the occurrence of the state with high activity levels of theta oscillations independent of alpha and the state with low-level alpha and high-level theta oscillations were significantly correlated with pain relief by deep brain stimulation. This study provides a reliable approach to identifying the dynamic neural states in LFPs with a low signal-to-noise ratio by using sparse representation based on wavelet packet transform. Furthermore, it may advance closed-loop deep

  16. Frutalin reduces acute and neuropathic nociceptive behaviours in rodent models of orofacial pain.

    Science.gov (United States)

    Damasceno, Marina B M V; de Melo Júnior, José de Maria A; Santos, Sacha Aubrey A R; Melo, Luana T M; Leite, Laura Hévila I; Vieira-Neto, Antonio E; Moreira, Renato de A; Monteiro-Moreira, Ana Cristina de O; Campos, Adriana R

    2016-08-25

    Orofacial pain is a highly prevalent clinical condition, yet difficult to control effectively with available drugs. Much attention is currently focused on the anti-inflammatory and antinociceptive properties of lectins. The purpose of this study was to evaluate the antinociceptive effect of frutalin (FTL) using rodent models of inflammatory and neuropathic orofacial pain. Acute pain was induced by formalin, glutamate or capsaicin (orofacial model) and hypertonic saline (corneal model). In one experiment, animals were pretreated with l-NAME and naloxone to investigate the mechanism of antinociception. The involvement of the lectin domain in the antinociceptive effect of FTL was verified by allowing the lectin to bind to its specific ligand. In another experiment, animals pretreated with FTL or saline were submitted to the temporomandibular joint formalin test. In yet another, animals were submitted to infraorbital nerve transection to induce chronic pain, followed by induction of thermal hypersensitivity using acetone. Motor activity was evaluated with the rotarod test. A molecular docking was performed using the TRPV1 channel. Pretreatment with FTL significantly reduced nociceptive behaviour associated with acute and neuropathic pain, especially at 0.5 mg/kg. Antinociception was effectively inhibited by l-NAME and d-galactose. In line with in vivo experiments, docking studies indicated that FTL may interact with TRPV1. Our results confirm the potential pharmacological relevance of FTL as an inhibitor of orofacial nociception in acute and chronic pain mediated by TRPA1, TRPV1 and TRPM8 receptor. Copyright © 2016. Published by Elsevier Ireland Ltd.

  17. Repetitive Treatment with Diluted Bee Venom Attenuates the Induction of Below-Level Neuropathic Pain Behaviors in a Rat Spinal Cord Injury Model.

    Science.gov (United States)

    Kang, Suk-Yun; Roh, Dae-Hyun; Choi, Jung-Wan; Ryu, Yeonhee; Lee, Jang-Hern

    2015-07-10

    The administration of diluted bee venom (DBV) into an acupuncture point has been utilized traditionally in Eastern medicine to treat chronic pain. We demonstrated previously that DBV has a potent anti-nociceptive efficacy in several rodent pain models. The present study was designed to examine the potential anti-nociceptive effect of repetitive DBV treatment in the development of below-level neuropathic pain in spinal cord injury (SCI) rats. DBV was applied into the Joksamli acupoint during the induction and maintenance phase following thoracic 13 (T13) spinal hemisection. We examined the effect of repetitive DBV stimulation on SCI-induced bilateral pain behaviors, glia expression and motor function recovery. Repetitive DBV stimulation during the induction period, but not the maintenance, suppressed pain behavior in the ipsilateral hind paw. Moreover, SCI-induced increase in spinal glia expression was also suppressed by repetitive DBV treatment in the ipsilateral dorsal spinal cord. Finally, DBV injection facilitated motor function recovery as indicated by the Basso-Beattie-Bresnahan rating score. These results indicate that the repetitive application of DBV during the induction phase not only decreased neuropathic pain behavior and glia expression, but also enhanced locomotor functional recovery after SCI. This study suggests that DBV acupuncture can be a potential clinical therapy for SCI management.

  18. Existence of a neuropathic pain component in patients with osteoarthritis of the knee.

    Science.gov (United States)

    Ohtori, Seiji; Orita, Sumihisa; Yamashita, Masaomi; Ishikawa, Tetsuhiro; Ito, Toshinori; Shigemura, Tomonori; Nishiyama, Hideki; Konno, Shin; Ohta, Hideyuki; Takaso, Masashi; Inoue, Gen; Eguchi, Yawara; Ochiai, Nobuyasu; Kishida, Shunji; Kuniyoshi, Kazuki; Aoki, Yasuchika; Arai, Gen; Miyagi, Masayuki; Kamoda, Hiroto; Suzkuki, Miyako; Nakamura, Junichi; Furuya, Takeo; Kubota, Gou; Sakuma, Yoshihiro; Oikawa, Yasuhiro; Suzuki, Masahiko; Sasho, Takahisa; Nakagawa, Koichi; Toyone, Tomoaki; Takahashi, Kazuhisa

    2012-07-01

    Pain from osteoarthritis (OA) is generally classified as nociceptive (inflammatory). Animal models of knee OA have shown that sensory nerve fibers innervating the knee are significantly damaged with destruction of subchondral bone junction, and induce neuropathic pain (NP). Our objective was to examine NP in the knees of OA patients using painDETECT (an NP questionnaire) and to evaluate the relationship between NP, pain intensity, and stage of OA. Ninety-two knee OA patients were evaluated in this study. Pain scores using Visual Analogue Scales (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), painDETECT, duration of symptoms, severity of OA using the Kellgren-Lawrence (KL) system, and amount of joint fluid were evaluated and compared using a Spearman's correlation coefficient by rank test. Our study identified at least 5.4% of our knee OA patients as likely to have NP and 15.2% as possibly having NP. The painDETECT score was significantly correlated with the VAS and WOMAC pain severity. Compared with the painDETECT score, there was a tendency for positive correlation with the KL grade, and tendency for negative correlation with the existence and amount of joint fluid, but these correlations were not significant. PainDETECT scores classified 5.4% of pain from knee OA as NP. NP tended to be seen in patients with less joint fluid and increased KL grade, both of which corresponded to late stages of OA. It is important to consider the existence of NP in the treatment of knee OA pain.

  19. Parents' perspective of their journey caring for a child with chronic neuropathic pain.

    Science.gov (United States)

    Gaughan, Veronica; Logan, Deirdre; Sethna, Navil; Mott, Sandra

    2014-03-01

    When a child has chronic pain, it affects the parents. Their response and how it is factored into their lives and family function was the phenomenon of interest that drove this study. The available literature was sparse, especially when the pain etiology was neuropathic. The purpose of this study was to describe the parents' perception of the pain journey from the initial occurrence of their child's pain through the labyrinth of treatment options to successful outcome, to gain a better understanding of parental beliefs about pain, and to learn how parental attitudes and behaviors relate to children's response to treatment for chronic pain. Qualitative descriptive design was used to better understand the phenomenon from those who were the experts because they had experienced it. Parents whose child was enrolled in a pain rehabilitation program participated in open-ended interviews. The children/adolescents were 8-18 years old and diagnosed with complex regional pain syndrome or a related chronic pain condition. During data immersion, the investigators uncovered the pervasive underlying themes of suffering and disempowerment. In addition, the multiple meaning elements were grouped into three categories and supportive subcategories labeled as follows: parent distress, with subcategories schism in parenting, searching, and disabled parenting; and lack of control, with the subcategories family/community, fear, and empowerment. The voices of parents were heard in their description of the exhausting and difficult journey in search of pain relief for their child. Their comments provided insight into how they defined the child's pain and their related parental role. Copyright © 2014 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  20. THE ORIGIN OF THE CONCEPT OF NEUROPATHIC PAIN IN EARLY MEDIEVAL PERSIA (9TH-12TH CENTURY CE).

    Science.gov (United States)

    Heydari, Mojtaba; Shams, Mesbah; Hashempur, Mohammad Hashem; Zargaran, Arman; Dalfardi, Behnam; Borhani-Haghighi, Afshin

    2015-01-01

    Neuropathic pain is supposed to be a post-renaissance described medical entity. Although it is often believed that John Fothergill (1712-1780) provided the first description of this condition in 1773, a review of the medieval Persian medical writings will show the fact that neuropathic pain was a medieval-originated concept. "Auojae Asab" [Nerve-originated Pain] was used as a medical term in medieval Persian medical literature for pain syndromes which etiologically originated from nerves. Physicians like Rhazes (d. 925 CE), Haly Abbas (d. 982 CE), Avicenna (d. 1037 CE), and Jorjani (d. 1137 CE) have discussed multiple aspects of nerve-originated pain including its classification, etiology, differentiating characteristics, different qualities, and pharmacologic and non-pharmacologic treatments. Recognizing medieval scholars' views on nerve-originated pain can lighten old historical origins of this concept.

  1. The β-lactam clavulanic acid mediates glutamate transport-sensitive pain relief in a rat model of neuropathic pain

    DEFF Research Database (Denmark)

    Kristensen, P J; Gegelashvili, G; Munro, G

    2017-01-01

    -regulates glutamate transporters both in vitro and in vivo. Crucially, a similar up-regulation of glutamate transporters in human spinal astrocytes by clavulanic acid supports the development of novel β-lactam-based analgesics, devoid of antibacterial activity, for the clinical treatment of chronic pain.......BACKGROUND: Following nerve injury, down-regulation of astroglial glutamate transporters (GluTs) with subsequent extracellular glutamate accumulation is a key factor contributing to hyperexcitability within the spinal dorsal horn. Some β-lactam antibiotics can up-regulate GluTs, one of which......, ceftriaxone, displays analgesic effects in rodent chronic pain models. METHODS: Here, the antinociceptive actions of another β-lactam clavulanic acid, which possesses negligible antibiotic activity, were compared with ceftriaxone in rats with chronic constriction injury (CCI)-induced neuropathic pain...

  2. Prolonged Suppression of Neuropathic Pain by Sequential Delivery of Lidocaine and Thalidomide Drugs Using PEGylated Graphene Oxide.

    Science.gov (United States)

    Song, Tieying; Gu, Kunfeng; Wang, Wenli; Wang, Hong; Yang, Yunliang; Yang, Lijun; Ma, Pengxu; Ma, Xiaojing; Zhao, Jianhui; Yan, Ruyu; Guan, Jiao; Wang, Chunping; Qi, Yan; Ya, Jian

    2015-11-01

    The management of patients with neuropathic pain is challenging. Monotherapy with a single pain relief drug may encounter different difficulties, such as short duration of efficacy and hence too many times of drug administration, and inadequate drug delivery. Recently, nanocarrier-based drug delivery systems have been proved to provide promising strategies for efficient drug loading, delivery, and release. In the present study, we developed poly(ethylene glycol) methyl ether functionalized graphene oxide (GO) bearing two commonly used drugs of lidocaine (LDC) and thalidomide (THD) as an agent for the treatment of neuropathic pain. The sequential drug release of LDC and THD from the developed LDC-THD-GO nanosheets exhibited a synergistic effect on neuropathic pain in vitro and in vivo, as evidenced by the increased pain threshold in mechanical allodynia and hyperalgesic response tests, and the improved inhibition of proinflammatory cytokines TNF-α, IL-1β, IL-6, and nitric oxide. We believed that the present study herein would hold promise for future development of a new generation of potent agents for neuropathic pain relief. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  3. MiR-19a targets suppressor of cytokine signaling 1 to modulate the progression of neuropathic pain

    OpenAIRE

    Wang, Conghui; Jiang, Qi; Wang, Min; Li, Dong

    2015-01-01

    Purpose: we aimed to investigate whether miR-19a is associated with neuropathic pain and elucidate the underlying regulatory mechanism. Methods: We established a neuropathic pain model of bilateral chronic constriction injury (bCCI). Then bCCI rats were injected with mo-miR-19a, siR-SOCS1 or blank expression vector through a microinjection syringe via an intrathecal catheter on 3 day before surgery and after surgery. Behavioral tests, such as mechanical allodynia, thermal hyperalgesia and ace...

  4. Acetaminophen and non-steroidal anti-inflammatory drugs interact with morphine and tramadol analgesia for the treatment of neuropathic pain in rats.

    Science.gov (United States)

    Shinozaki, Tomonari; Yamada, Toshihiko; Nonaka, Takahiro; Yamamoto, Tatsuo

    2015-06-01

    Although non-steroidal anti-inflammatory drugs and acetaminophen have no proven efficacy against neuropathic pain, they are frequently prescribed for neuropathic pain patients. We examined whether the combination of opioids (tramadol and morphine) with indomethacin or acetaminophen produce favorable effects on neuropathic pain and compared the efficacy for neuropathic pain with that for inflammatory pain. The carrageenan model was used as the inflammatory pain model while the tibial neuroma transposition (TNT) model was used as the neuropathic pain model. The tibial nerve is transected in the TNT model, with the tibial nerve stump then transpositioned to the lateral aspect of the hindlimb. Neuropathic pain (mechanical allodynia and neuroma pain) is observed after TNT injury. Drugs were administered orally. In the carrageenan model, all drugs produced anti-allodynic effects and all drug combinations, but not tramadol + indomethacin combination, produced synergistic anti-allodynic effects. In the TNT model, tramadol and morphine, but not acetaminophen and indomethacin, produced anti-neuropathic pain effects. In the combination, with the exception of morphine + acetaminophen combination, both acetaminophen and indomethacin reduced the 50% effective dose (ED50) of tramadol and morphine as compared with the ED50s for the single drug study in the TNT model. The ED50s of tramadol and morphine in the carrageenan combination test were not statistically significantly different from the ED50s in the TNT model combination study. The combination of opioids with indomethacin or acetaminophen produced a synergistic analgesic effect both in inflammatory and neuropathic pain with some exceptions. The efficacy of these combinations for neuropathic pain was not different from that for inflammatory pain.

  5. Mechanisms-based classifications of musculoskeletal pain: part 2 of 3: symptoms and signs of peripheral neuropathic pain in patients with low back (± leg) pain.

    LENUS (Irish Health Repository)

    Smart, Keith M

    2012-08-01

    As a mechanisms-based classification of pain \\'peripheral neuropathic pain\\' (PNP) refers to pain arising from a primary lesion or dysfunction in the peripheral nervous system. Symptoms and signs associated with an assumed dominance of PNP in patients attending for physiotherapy have not been extensively studied. The purpose of this study was to identify symptoms and signs associated with a clinical classification of PNP in patients with low back (± leg) pain. Using a cross-sectional, between-subjects design; four hundred and sixty-four patients with low back (± leg) pain were assessed using a standardised assessment protocol. Patients\\' pain was assigned a mechanisms-based classification based on experienced clinical judgement. Clinicians then completed a clinical criteria checklist specifying the presence or absence of various clinical criteria. A binary logistic regression analysis with Bayesian model averaging identified a cluster of two symptoms and one sign predictive of PNP, including: \\'Pain referred in a dermatomal or cutaneous distribution\\

  6. Symptom-Based Treatment of Neuropathic Pain in Spinal Cord-Injured Patients: A Randomized Crossover Clinical Trial.

    Science.gov (United States)

    Min, Kyunghoon; Oh, Yoongul; Lee, Sang-Hyuk; Ryu, Ju Seok

    2016-05-01

    The objective of this study was to identify the differences in medication effect according to pain characteristics in spinal cord-injured patients. This study is a prospective, randomized, crossover study. Fifty-five patients and 66 locations of neuropathic pain were included. Pain was classified into four spontaneous characteristics and three evoked pain characteristics. Oxcarbazepine (Na channel blocker) and pregabalin (calcium channel α2-δ ligand medication) were tried. Patients were divided into two groups: evoked pain present and evoked pain absent. Overall average visual analog scale was obtained. Oxcarbazepine was significantly more effective for patients without evoked pain than in those with it for electrical, burning, and pricking pain. The effect of pregabalin was not different regarding the presence or absence of evoked pain for all pain categories, except burning pain. In patients with evoked pain, pregabalin was shown to be significantly more effective for electrical pain, allodynia, and heat hyperalgesia than oxcarbazepine. In the evoked pain absent group, oxcarbazepine showed greater improvement than pregabalin but was not significant. In summary, the phenotype of neuropathic pain was associated with the efficacy of different pharmacologic treatments. Symptom-based treatment, therefore, can lead to more efficient analgesia.

  7. Development of a mouse model of neuropathic pain following photochemically induced ischemia in the sciatic nerve.

    Science.gov (United States)

    Hao, J X; Blakeman, K H; Yu, W; Hultenby, K; Xu, X J; Wiesenfeld-Hallin, Z

    2000-05-01

    A mouse model of neuropathic pain was developed by a photochemically induced ischemic nerve injury in normal male C57/BL6 mice. The ischemia was induced by unilateral irradiation of the sciatic nerve with an argon ion laser after intravenous administration of a photosensitizing dye, erythrosin B. The nerve injury resulted in a significant decrease in withdrawal threshold of the hindpaws to mechanical stimulation with von Frey hairs, as well as increased responsiveness to cold and heat stimulation. The mice, however, did not exhibit overt spontaneous pain-like behaviors. The evoked pain-related behaviors were observed bilaterally, although the ipsilateral changes were greater than on the contralateral side. The extent and time course of the behavioral changes were related to the duration of laser irradiation, with 1-min exposure producing the most consistent effect. Morphological examination at the light microscopic level revealed partial demyelination and axonal degeneration of the large myelinated fibers at the epicenter of the lesion 1 week postirradiation. The extent of the damage was correlated with the duration of irradiation. Injury and loss of unmyelinated fibers were also observed at the electronmicroscopic level. We conclude that an intravascular photochemical reaction leading to ischemia results in graded damage to the sciatic nerve in mice. Moreover, the nerve injury is associated with the development of abnormal pain-related behaviors. Both the behavioral and the morphological changes are correlated with the duration of irradiation. These results establish a mouse model of partial nerve injury with neuropathic pain-like behaviors which may be useful in studies using genetically modified mice. Copyright 2000 Academic Press.

  8. Topical gabapentin gel alleviates allodynia and hyperalgesia in the chronic sciatic nerve constriction injury neuropathic pain model.

    Science.gov (United States)

    Shahid, M; Subhan, F; Ahmad, N; Ali, G; Akbar, S; Fawad, K; Sewell, R D E

    2017-04-01

    Systemic gabapentin is a mainstay treatment for neuropathic pain though there are side-effects. Localized therapy may curtail such side-effects so a topical gabapentin dermal application was examined in the chronic constriction injury (CCI) model of neuropathic pain. Partial denervation CCI was achieved by rat sciatic nerve ligation. Gabapentin gel (10% w/w) was applied three times daily on the ipsilateral or contralateral plantar surface of the hind-paw, whereas in a concurrent systemic study, gabapentin was intraperitoneally administered daily (75 mg/kg) for 30 days. Tests for static- and dynamic-mechano-allodynia [paw withdrawal threshold (PWT) to von Frey filament application and latency (PWL) to light brushing], cold-allodynia [paw withdrawal duration (PWD) to acetone], heat- (PWL and PWD) and mechano-hyperalgesia (PWD to pin prick) were utilized to assess pain, whereas effects on locomotion (open field) and motor balance (rotarod and footprint analysis) were measured on days 5-30 post surgery. Topical application of gabapentin gel ipsilaterally but not contralaterally alleviated CCI-induced static- (days 10-30) and dynamic-allodynia (days 15-30), suppressed cold-allodynia (days 10-30), heat- (days 15-30) and mechano-hyperalgesia (days 5-30) indicating a local action. Systemic gabapentin exhibited similar pain profiles but was associated with motor impairment. The gabapentin gel formulation afforded desirable neuropathic pain alleviating effects devoid of unwanted systemic side-effects. These outcomes disclose an expedient pharmacological validation of the effectiveness of topical gabapentin gel against an extensive range of nociceptive stimulus modalities utilizing the CCI-induced neuropathic pain model. They also advocate further clinical studies on topical gabapentin with regard to certain neuropathic pain syndromes. Systemic gabapentin neuropathic pain management carries side-effects ostensibly preventable by localized therapy. This study validates the

  9. Development and statistical optimization of nefopam hydrochloride loaded nanospheres for neuropathic pain using Box–Behnken design

    Directory of Open Access Journals (Sweden)

    S. Sukhbir

    2016-09-01

    Full Text Available Nefopam hydrochloride (NFH is a non-opioid centrally acting analgesic drug used to treat chronic condition such as neuropathic pain. In current research, sustained release nefopam hydrochloride loaded nanospheres (NFH-NS were auspiciously synthesized using binary mixture of eudragit RL 100 and RS 100 with sorbitan monooleate as surfactant by quasi solvent diffusion technique and optimized by 35 Box–Behnken designs to evaluate the effects of process and formulation variables. Fourier transform infrared spectroscopy (FTIR, differential scanning calorimetric (DSC and X-ray diffraction (XRD affirmed absence of drug–polymer incompatibility and confirmed formation of nanospheres. Desirability function scrutinized by design-expert software for optimized formulation was 0.920. Optimized batch of NFH-NS had mean particle size 328.36 nm ± 2.23, % entrapment efficiency (% EE 84.97 ± 1.23, % process yield 83.60 ± 1.31 and % drug loading (% DL 21.41 ± 0.89. Dynamic light scattering (DLS, zeta potential analysis and scanning electron microscopy (SEM validated size, charge and shape of nanospheres, respectively. In-vitro drug release study revealed biphasic release pattern from optimized nanospheres. Korsmeyer Peppas found excellent kinetics model with release exponent less than 0.45. Chronic constricted injury (CCI model of optimized NFH-NS in Wistar rats produced significant difference in neuropathic pain behavior (p < 0.05 as compared to free NFH over 10 h indicating sustained action. Long term and accelerated stability testing of optimized NFH-NS revealed degradation rate constant 1.695 × 10−4 and shelf-life 621 days at 25 ± 2 °C/60% ± 5% RH.

  10. Development and statistical optimization of nefopam hydrochloride loaded nanospheres for neuropathic pain using Box-Behnken design.

    Science.gov (United States)

    Sukhbir, S; Yashpal, S; Sandeep, A

    2016-09-01

    Nefopam hydrochloride (NFH) is a non-opioid centrally acting analgesic drug used to treat chronic condition such as neuropathic pain. In current research, sustained release nefopam hydrochloride loaded nanospheres (NFH-NS) were auspiciously synthesized using binary mixture of eudragit RL 100 and RS 100 with sorbitan monooleate as surfactant by quasi solvent diffusion technique and optimized by 3 5 Box-Behnken designs to evaluate the effects of process and formulation variables. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetric (DSC) and X-ray diffraction (XRD) affirmed absence of drug-polymer incompatibility and confirmed formation of nanospheres. Desirability function scrutinized by design-expert software for optimized formulation was 0.920. Optimized batch of NFH-NS had mean particle size 328.36 nm ± 2.23, % entrapment efficiency (% EE) 84.97 ± 1.23, % process yield 83.60 ± 1.31 and % drug loading (% DL) 21.41 ± 0.89. Dynamic light scattering (DLS), zeta potential analysis and scanning electron microscopy (SEM) validated size, charge and shape of nanospheres, respectively. In-vitro drug release study revealed biphasic release pattern from optimized nanospheres. Korsmeyer Peppas found excellent kinetics model with release exponent less than 0.45. Chronic constricted injury (CCI) model of optimized NFH-NS in Wistar rats produced significant difference in neuropathic pain behavior ( p  accelerated stability testing of optimized NFH-NS revealed degradation rate constant 1.695 × 10 -4 and shelf-life 621 days at 25 ± 2 °C/60% ± 5% RH.

  11. Delta-opioid receptor analgesia is independent of microglial activation in a rat model of