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Yanagimura H, Sasaki M, Baba H, Kamiya Y. Influence of the descending pain-inhibiting serotonergic pathway on the antihyperalgesic effect of gabapentin in neuropathic pain model rats. Neurosci Res 2024; 202:20-29. [PMID: 37944901 DOI: 10.1016/j.neures.2023.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/29/2023] [Accepted: 11/05/2023] [Indexed: 11/12/2023]
Abstract
Gabapentinoids are used worldwide as first-line agents for the treatment of neuropathic pain. Accumulating evidence indicates that one of the antihyperalgesic mechanisms of gabapentinoids is through activation of the noradrenergic pathway of the descending pain inhibition system. However, the involvement of the serotonin pathway is unclear. We investigated the effects of gabapentin (GBP) on the serotonergic pathway of the descending inhibitory system using the spinal nerve ligation (SNL) rat model. As in previous reports, administration of GBP to SNL rats improved paw withdrawal thresholds (PWT). Intrathecally administered serotonin receptor antagonists abolished GBP's amelioration in PWT. GBP did not ameliorate PWT in noradrenaline-depleted SNL rats by DSP-4. However, GBP ameliorated PWT in serotonin-depleted SNL rats by para-chlorophenylalanine, which was not inhibited by intrathecal administration of a serotonin receptor antagonist. Immunohistochemical analysis of serotonin in the spinal dorsal horn revealed a slight, albeit statistically insignificant, increase in 5-HT levels in SNL rats compared to naive rats. However, no apparent changes were observed before or after GBP administration in naive and SNL rats. In conclusion, the involvement of the serotonergic pathway in the antihyperalgesic effects of GBP on the spinal cord is secondary, although it cooperates with the noradrenergic system to produce analgesia.
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Affiliation(s)
- Harue Yanagimura
- Division of Anesthesiology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo Ward, Niigata City 951-8510, Japan
| | - Mika Sasaki
- Division of Anesthesiology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo Ward, Niigata City 951-8510, Japan; Department of Anesthesiology and Pain Medicine, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu City 501-1194, Japan
| | - Hiroshi Baba
- Division of Anesthesiology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo Ward, Niigata City 951-8510, Japan
| | - Yoshinori Kamiya
- Division of Anesthesiology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo Ward, Niigata City 951-8510, Japan; Department of Anesthesiology and Pain Medicine, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu City 501-1194, Japan.
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2
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Mohammad A, Laboulaye MA, Shenhar C, Dobberfuhl AD. Mechanisms of oxidative stress in interstitial cystitis/bladder pain syndrome. Nat Rev Urol 2024:10.1038/s41585-023-00850-y. [PMID: 38326514 DOI: 10.1038/s41585-023-00850-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2023] [Indexed: 02/09/2024]
Abstract
Interstitial cystitis/bladder pain syndrome (IC/BPS) is characterized by bladder and/or pelvic pain, increased urinary urgency and frequency and nocturia. The pathophysiology of IC/BPS is poorly understood, and theories include chronic inflammation, autoimmune dysregulation, bacterial cystitis, urothelial dysfunction, deficiency of the glycosaminoglycan (GAG) barrier and urine cytotoxicity. Multiple treatment options exist, including behavioural interventions, oral medications, intravesical instillations and procedures such as hydrodistension; however, many clinical trials fail, and patients experience an unsatisfactory treatment response, likely owing to IC/BPS phenotype heterogeneity and the use of non-targeted interventions. Oxidative stress is implicated in the pathogenesis of IC/BPS as reactive oxygen species impair bladder function via their involvement in multiple molecular mechanisms. Kinase signalling pathways, nociceptive receptors, mast-cell activation, urothelial dysregulation and circadian rhythm disturbance have all been linked to reactive oxygen species and IC/BPS. However, further research is necessary to fully uncover the role of oxidative stress in the pathways driving IC/BPS pathogenesis. The development of new models in which these pathways can be manipulated will aid this research and enable further investigation of promising therapeutic targets.
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Affiliation(s)
- Ashu Mohammad
- Department of Urology, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Mallory A Laboulaye
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Chen Shenhar
- Department of Urology, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Amy D Dobberfuhl
- Department of Urology, Stanford University School of Medicine, Palo Alto, CA, USA.
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3
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Schaffer J, Fogelman N, Seo D, Sinha R. Chronic pain, chronic stress and substance use: overlapping mechanisms and implications. FRONTIERS IN PAIN RESEARCH 2023; 4:1145934. [PMID: 37415830 PMCID: PMC10320206 DOI: 10.3389/fpain.2023.1145934] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 06/05/2023] [Indexed: 07/08/2023] Open
Abstract
Chronic pain is among the most common reasons adults in the U.S. seek medical care. Despite chronic pain's substantial impact on individuals' physical, emotional, and financial wellness, the biologic underpinnings of chronic pain remain incompletely understood. Such deleterious impact on an individuals' wellness is also manifested in the substantial co-occurrence of chronic stress with chronic pain. However, whether chronic stress and adversity and related alcohol and substance misuse increases risk of developing chronic pain, and, if so, what the overlapping psychobiological processes are, is not well understood. Individuals suffering with chronic pain find alleviation through prescription opioids as well as non-prescribed cannabis, alcohol, and other drugs to control pain, and use of these substances have grown significantly. Substance misuse also increases experience of chronic stress. Thus, given the evidence showing a strong correlation between chronic stress and chronic pain, we aim to review and identify overlapping factors and processes. We first explore the predisposing factors and psychologic features common to both conditions. This is followed by examining the overlapping neural circuitry of pain and stress in order to trace a common pathophysiologic processes for the development of chronic pain and its link to substance use. Based on the previous literature and our own findings, we propose a critical role for ventromedial prefrontal cortex dysfunction, an overlapping brain area associated with the regulation of both pain and stress that is also affected by substance use, as key in the risk of developing chronic pain. Finally, we identify the need for future research in exploring the role of medial prefrontal circuits in chronic pain pathology. Critically, in order to alleviate the enormous burden of chronic pain without exacerbating the co-occurring substance misuse crisis, we emphasize the need to find better approaches to treat and prevent chronic pain.
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Affiliation(s)
| | | | | | - R. Sinha
- Department of Psychiatry and the Yale Stress Center, Yale University School of Medicine, New Haven, CT, United States
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4
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Di Cesare F, Negro V, Ravasio G, Villa R, Draghi S, Cagnardi P. Gabapentin: Clinical Use and Pharmacokinetics in Dogs, Cats, and Horses. Animals (Basel) 2023; 13:2045. [PMID: 37370556 DOI: 10.3390/ani13122045] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 06/16/2023] [Accepted: 06/19/2023] [Indexed: 06/29/2023] Open
Abstract
Gabapentin is an anticonvulsant drug, which presents an established clinical efficacy in human patients for the management of refractory partial seizures, secondarily generalized tonic-clonic seizures, and for the control of chronic neuropathic pain. Gabapentin was synthesized as a structural analogue of the inhibitory neurotransmitter GABA, with GABA-mimetic effects, able to cross the blood-brain barrier. In veterinary medicine, is extra-label used in combination with other treatments to control seizures when other drugs are no longer effective or become toxic or for neuropathic pain treatment and anxiety. This review aimed to clarify gabapentin use and pharmacokinetic aspects to promote conscious use in dogs, cats, and horses. In dogs, gabapentin was beneficial in the treatment of epilepsy, as well as chronic, neuropathic, and post-operative pain, as well as anxiety. In cats, it showed efficacy in post-ovariohysterectomy-related pain and in anxiety management. In horses, gabapentin has been administered as an analgesic for chronic pain management. In conclusion, when used in combination with other drugs, gabapentin can be considered an interesting therapeutic option for the treatment of neuropathic diseases and analgesia in postoperative and chronic pain. However, despite its beneficial use in different clinical settings, further trials and pharmacokinetic studies are needed for the definition of an effective dosage regimen through proper pharmacokinetic/pharmacodynamic correlation in dogs, cats, and horses.
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Affiliation(s)
- Federica Di Cesare
- Department of Veterinary Medicine and Animal Sciences, Università degli Studi di Milano, Via dell'Università 6, 26900 Lodi, Italy
| | - Viviana Negro
- Department of Veterinary Medicine and Animal Sciences, Università degli Studi di Milano, Via dell'Università 6, 26900 Lodi, Italy
| | - Giuliano Ravasio
- Department of Veterinary Medicine and Animal Sciences, Università degli Studi di Milano, Via dell'Università 6, 26900 Lodi, Italy
| | - Roberto Villa
- Department of Veterinary Medicine and Animal Sciences, Università degli Studi di Milano, Via dell'Università 6, 26900 Lodi, Italy
| | - Susanna Draghi
- Department of Veterinary Medicine and Animal Sciences, Università degli Studi di Milano, Via dell'Università 6, 26900 Lodi, Italy
| | - Petra Cagnardi
- Department of Veterinary Medicine and Animal Sciences, Università degli Studi di Milano, Via dell'Università 6, 26900 Lodi, Italy
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5
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Donertas-Ayaz B, Caudle RM. Locus coeruleus-noradrenergic modulation of trigeminal pain: Implications for trigeminal neuralgia and psychiatric comorbidities. NEUROBIOLOGY OF PAIN (CAMBRIDGE, MASS.) 2023; 13:100124. [PMID: 36974102 PMCID: PMC10038791 DOI: 10.1016/j.ynpai.2023.100124] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 03/15/2023] [Accepted: 03/15/2023] [Indexed: 03/29/2023]
Abstract
Trigeminal neuralgia is the most common neuropathic pain involving the craniofacial region. Due to the complex pathophysiology, it is therapeutically difficult to manage. Noradrenaline plays an essential role in the modulation of arousal, attention, cognitive function, stress, and pain. The locus coeruleus, the largest source of noradrenaline in the brain, is involved in the sensory and emotional processing of pain. This review summarizes the knowledge about the involvement of noradrenaline in acute and chronic trigeminal pain conditions and how the activity of the locus coeruleus noradrenergic neurons changes in response to acute and chronic pain conditions and how these changes might be involved in pain-related comorbidities including anxiety, depression, and sleep disturbance.
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Affiliation(s)
| | - Robert M. Caudle
- Corresponding author at: Department of Oral and Maxillofacial Surgery, University of Florida College of Dentistry, PO Box 100416, 1395 Center Drive, Gainesville, FL 32610, United States.
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6
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Bravo L, Mariscal P, Llorca-Torralba M, López-Cepero JM, Nacher J, Berrocoso E. Altered expression of vesicular glutamate transporter-2 and cleaved caspase-3 in the locus coeruleus of nerve-injured rats. Front Mol Neurosci 2022; 15:918321. [PMID: 35966012 PMCID: PMC9363707 DOI: 10.3389/fnmol.2022.918321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 07/04/2022] [Indexed: 11/15/2022] Open
Abstract
Neuropathic pain is a debilitating chronic condition provoked by a lesion in the nervous system and it induces functional alterations to the noradrenergic locus coeruleus (LC), affecting distinct dimensions of pain, like sensorial hypersensitivity, pain-induced depression, and anxiety. However, the neurobiological changes induced by nerve damage in the LC remain unclear. Here, we analyzed excitatory and inhibitory inputs to the LC, as well as the possible damage that noradrenergic neurons suffer after the induction of neuropathic pain through chronic constriction injury (CCI). Neuropathic pain was induced in male Sprague-Dawley rats, and the expression of the vesicular glutamate transporter 1 or 2 (VGLUT1 or VGLUT2), vesicular GABA transporter (VGAT), and cleaved caspase-3 (CC3) was analyzed by immunofluorescence 7 (CCI7d) or 28 days after the original lesion (CCI28d). While no significant differences in the density of VGLUT1 puncta were evident, CCI7d induced a significant increase in the perisomatic VGLUT2/VGAT ratio relative to Sham-operated and CCI28d animals. By contrast, when the entire region of LC is evaluated, there was a significant reduction in the density of VGLUT2 puncta in CCI28d animals, without changes in VGLUT2/VGAT ratio relative to the CCI7d animals. Additionally, changes in the noradrenergic soma size, and a lower density of mitochondria and lysosomes were evident in CCI28d animals. Interestingly, enhanced expression of the apoptotic marker CC3 was also evident in the CCI28d rats, mainly co-localizing with glial fibrillary acidic protein but not with any neuronal or noradrenergic marker. Overall, short-term pain appears to lead to an increase of markers of excitatory synapses in the perisomatic region of noradrenergic cells in the LC, an effect that is lost after long-term pain, which appears to activate apoptosis.
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Affiliation(s)
- Lidia Bravo
- Neuropsychopharmacology and Psychobiology Research Group, Department of Neuroscience, University of Cádiz, Cádiz, Spain
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
| | - Patricia Mariscal
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Cádiz, Spain
| | - Meritxell Llorca-Torralba
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
- Neuropsychopharmacology and Psychobiology Research Group, Department of Cell Biology and Histology, University of Cádiz, Cádiz, Spain
| | - Jose María López-Cepero
- Neuropsychopharmacology and Psychobiology Research Group, Department of Cell Biology and Histology, University of Cádiz, Cádiz, Spain
| | - Juan Nacher
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
- Fundación Investigación Hospital Clínico de Valencia, INCLIVA, Valencia, Spain
| | - Esther Berrocoso
- Instituto de Investigación e Innovación Biomédica de Cádiz, INiBICA, Hospital Universitario Puerta del Mar, Cádiz, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
- Neuropsychopharmacology and Psychobiology Research Group, Department of Psychology, University of Cádiz, Cádiz, Spain
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7
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Du Z, Chen H, Cai Y, Zhou Z. Pharmacological use of gamma-aminobutyric acid derivatives in osteoarthritis pain management: a systematic review. BMC Rheumatol 2022; 6:28. [PMID: 35538592 PMCID: PMC9092798 DOI: 10.1186/s41927-022-00257-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 03/07/2022] [Indexed: 02/08/2023] Open
Abstract
Background Pain is the major complication of osteoarthritis (OA) patients and is a decisive symptom for medical intervention. Gamma-aminobutyric acid (GABA) derivatives are optional painkillers but not widely used in pain management of OA patients. We synthesized the efficacy and safety of GABA derivatives for OA pain management. Methods We searched Medline, Cochrane CENTRAL, Embase, and ClinicalTrals.gov from inception to 13 October 2021 and included randomized controlled trials (RCTs) comparing the efficacy and safety of GABA derivatives with placebo or standard control in OA pain management. Two independent reviewers extracted data and assessed these studies for risk of bias using Cochrane Collaboration’s tool for RCT. Results In total, three eligible RCTs (n = 3) meeting the eligibility criteria were included. Among these RCTs, one focused on hand OA pain management, while two RCTs focused on knee OA. In hand OA, pregabalin reduced numerical rating scale (NRS) score and the Australian/Canadian Osteoarthritis Hand Index (AUSCAN) pain score significantly compared with placebo, and caused 55 AEs. In knee OA, pregabalin reduced visual analogue scale (VAS) score and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain score significantly with no recorded adverse event (AE). Meanwhile, in knee OA, gabapentin reduced both VAS score and WOMAC pain score compared with acetaminophen and caused 9 AEs. Conclusions GABA derivatives seem to be effective and safe in OA pain management. However, future researches with large sample size are needed to further prove the efficacy of GABA derivatives in OA pain control. Trial registration: CRD42021240225. Supplementary Information The online version contains supplementary material available at 10.1186/s41927-022-00257-z.
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Affiliation(s)
- Ze Du
- Department of Orthopedics, Research Institute of Orthopedics, West China Hospital/West China School of Medicine, Sichuan University, Chengdu, 610041, China
| | - Hanxiao Chen
- Department of Obstetrics and Gynaecology, West China Second University Hospital, Sichuan University, Chengdu, 610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children of the Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, 610041, China
| | - Yongrui Cai
- Department of Orthopedics, Research Institute of Orthopedics, West China Hospital/West China School of Medicine, Sichuan University, Chengdu, 610041, China
| | - Zongke Zhou
- Department of Orthopedics, Research Institute of Orthopedics, West China Hospital/West China School of Medicine, Sichuan University, Chengdu, 610041, China.
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8
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Gadgeteering for Pain Relief: The 2021 John W. Severinghaus Lecture on Translational Science. Anesthesiology 2022; 136:888-900. [PMID: 35482967 DOI: 10.1097/aln.0000000000004207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In this first memorial lecture after John Severinghaus's death in 2021, the author traces his journey as a physician-scientist, using the framework of the hero's journey as described by the author Joseph Campbell 40 to 50 yr ago, and parallels that journey to his own. The author discusses how each were gadgeteers: Severinghaus in a creative engineering way, while the author's approach was asking simple questions translating basic research in pain from animals to humans. The classic hero's journey of departure to achieve a goal, then trials, transformation, and finally, returning with benefits to the individual and others is translated to the common physician-scientist career with motivations progressing from "I will show" to "I wonder if" to "I wonder why." Critical to this journey is self-questioning, openness to new ideas, and realizing that progress occurs through failure as much as success.
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9
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Yoshizumi M, Watanabe C, Mizoguchi H. Gabapentin reduces painful bladder hypersensitivity in rats with lipopolysaccharide-induced chronic cystitis. Pharmacol Res Perspect 2021; 9:e00697. [PMID: 33340266 PMCID: PMC7749515 DOI: 10.1002/prp2.697] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/05/2020] [Accepted: 11/05/2020] [Indexed: 12/13/2022] Open
Abstract
Although interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic condition causing bladder pain and urinary symptoms, effective treatments have not been established. The aim of this study was to adapt a chronic cystitis model in rats using lipopolysaccharide (LPS), which reflects IC/BPS pathology, and characterize the model's histological and behavioral effects. Furthermore, we investigated the effect of an α2 δ subunit ligand, gabapentin (GBP), on bladder hypersensitivity of rats with chronic cystitis. Cystitis models were created by repeated intravesical injections of LPS. In the histological examination, the LPS-injected group had greater inflammatory response, fibrosis, and abnormally thick re-epithelialization. In the LPS-injected group, LPS prompted hyperalgesia in both the lower abdomen and hind paw regions after day 1 of the first injection compared with the saline-injected controls, without any recovery for 21 days at least. During cystometry, the LPS-injected group showed bladder hyperactivity at all times. Systemic administration of GBP reduced cystitis-related pain due to chronic inflammation and reduced the increased frequency of voiding in the LPS-injected group. These results suggest that repeated intravesical injections of LPS induce long-lasting bladder inflammation, pain, and overactivity in rats, while GBP is effective in the management of those symptoms in this chronic cystitis model. The current study identifies a relatively simple method to develop an animal model for chronic cystitis and provides evidence that GBP may be an effective treatment option for patients with IC/BPS.
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Affiliation(s)
- Masaru Yoshizumi
- Department of Physiology and Anatomy Faculty of Pharmaceutical SciencesTohoku Medical and Pharmaceutical UniversitySendaiJapan
| | - Chizuko Watanabe
- Department of Physiology and Anatomy Faculty of Pharmaceutical SciencesTohoku Medical and Pharmaceutical UniversitySendaiJapan
| | - Hirokazu Mizoguchi
- Department of Physiology and Anatomy Faculty of Pharmaceutical SciencesTohoku Medical and Pharmaceutical UniversitySendaiJapan
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10
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Tagami K, Yoshizumi M, Inoue A, Matoba M. Effectiveness of Gabapentinoids for Cancer-related Rectal and Vesical Tenesmus: Report of Four Cases. Indian J Palliat Care 2020; 26:381-384. [PMID: 33311883 PMCID: PMC7725173 DOI: 10.4103/ijpc.ijpc_203_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 12/31/2019] [Indexed: 11/06/2022] Open
Abstract
Gabapentinoids could be assumed to relieve cancer-related rectal/vesical tenesmus based on their pharmacological mechanism. Four patients were refractory for cancer-related rectal/vesical tenesmus although their opioid doses were titrated up. Symptom intensity difference (SID) between initiation and follow-up after 24, 48, and 72 h and daily changes in the frequency of urination, defecation, opioid rescue doses, presence of sleep disruption, and dose of regular opioid medication were evaluated. The median reductions in daily discomfort measured as SID between baseline and follow-up after 24, 48, and 72 h were 87.5%, 70.0%, and 80.0%, respectively, while those in daily pain intensity were 75%, 66.7%, and 66.7%, respectively. The initiation dose of gabapentin was 200 or 400 mg/day and that of pregabalin was 75 mg/day in one patient. Gabapentinoids were effective at low doses administered over a short duration to patients with refractory cancer-related rectal/vesical tenesmus.
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Affiliation(s)
- Keita Tagami
- Department of Palliative Medicine, Tohoku University School of Medicine, Sendai, Japan.,Department of Palliative Medicine, National Cancer Center Hospital, Tokyo, Japan
| | - Masaru Yoshizumi
- Department of Physiology and Anatomy, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Akira Inoue
- Department of Palliative Medicine, Tohoku University School of Medicine, Sendai, Japan
| | - Motohiro Matoba
- Department of Palliative Medicine, National Cancer Center Hospital, Tokyo, Japan.,Department of Palliative Medicine, Aomori Prefectural Central Hospital, Aomori, Japan
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11
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Orhurhu MS, Chu R, Claus L, Roberts J, Salisu B, Urits I, Orhurhu E, Viswanath O, Kaye AD, Kaye AJ, Orhurhu V. Neuropathic Pain and Sickle Cell Disease: a Review of Pharmacologic Management. Curr Pain Headache Rep 2020; 24:52. [PMID: 32705357 DOI: 10.1007/s11916-020-00885-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE OF REVIEW Sickle cell disease (SCD) remains among the most common and severe monogenic disorders present in the world today. Although sickle cell pain has been traditionally characterized as nociceptive, a significant portion of sickle cell patients has reported neuropathic pain symptoms. Our review article will discuss clinical aspects of SCD-related neuropathic pain, epidemiology of neuropathic pain among individuals with SCD, pain mechanisms, and current and future potential pharmacological interventions. RECENT FINDINGS Neuropathic pain in SCD is a complicated condition that often has a lifelong and significant negative impact on life; therefore, improved pain management is considered a significant and unmet need. Neuropathic pain mechanisms are heterogeneous, and the difficulty in determining their individual contribution to specific pain types may contribute to poor treatment outcomes in this population. Our review article outlines several pharmacological modalities which may be employed to treat neuropathic pain in SCD patients.
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Affiliation(s)
- Mariam Salisu Orhurhu
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Robert Chu
- Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Lauren Claus
- Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Jacob Roberts
- Johns Hopkins School of Medicine, Baltimore, MD, USA
| | | | - Ivan Urits
- Department of Anesthesia, Critical Care, and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Ave, Boston, MA, 02215, USA
| | - Ejovwoke Orhurhu
- Massachusetts College of Pharmacy and Health Sciences, Boston, MA, USA
| | - Omar Viswanath
- Valley Anesthesiology and Pain Consultants, Phoenix, AZ, USA.,Department of Anesthesiology, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.,Department of Anesthesiology, Creighton University School of Medicine, Omaha, NE, USA.,Department of Anesthesiology, Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | - Alan D Kaye
- Valley Anesthesiology and Pain Consultants, Phoenix, AZ, USA.,Department of Anesthesiology, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.,Department of Anesthesiology, Creighton University School of Medicine, Omaha, NE, USA.,Department of Anesthesiology, Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | - Aaron J Kaye
- Department of Anesthesiology, Medical University South Carolina, Charleston, SC, USA
| | - Vwaire Orhurhu
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
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12
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Anton RF, Latham P, Voronin K, Book S, Hoffman M, Prisciandaro J, Bristol E. Efficacy of Gabapentin for the Treatment of Alcohol Use Disorder in Patients With Alcohol Withdrawal Symptoms: A Randomized Clinical Trial. JAMA Intern Med 2020; 180:728-736. [PMID: 32150232 PMCID: PMC7063541 DOI: 10.1001/jamainternmed.2020.0249] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
IMPORTANCE Although an estimated 30 million people meet criteria for alcohol use disorder (AUD), few receive appropriate pharmacotherapy. A more personalized, symptom-specific, approach might improve efficacy and acceptance. OBJECTIVE To examine whether gabapentin would be useful in the treatment of AUD, especially in those with the most alcohol withdrawal symptoms. DESIGN, SETTING, AND PARTICIPANTS This double-blind randomized clinical trial conducted between November 2014 and June 2018 evaluated gabapentin vs placebo in community-recruited participants screened and treated in an academic outpatient setting over a 16-week treatment period. A total of 145 treatment-seeking individuals who met Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) criteria for AUD and were not receiving other AUD intervention were screened, and 96 who also met recent alcohol withdrawal criteria were randomized to treatment after 3 abstinent days. Daily drinking was recorded, and percentage of disialo carbohydrate-deficient transferrin in the blood, a heavy drinking marker, was collected at baseline and monthly during treatment. INTERVENTIONS Gabapentin up to 1200 mg/d, orally, vs placebo along with 9 medical management visits (20 minutes each). MAIN OUTCOMES AND MEASURES The percentage of individuals with no heavy drinking days and those with total abstinence were compared between treatment groups and further evaluated based on prestudy alcohol withdrawal symptoms. RESULTS Of 96 randomized individuals, 90 were evaluable (44 in the gabapentin arm and 46 in the placebo arm), with a mean (SD) age of 49.6 (10.1) years; 69 were men (77%) and 85 were white (94%). The evaluable participants had 83% baseline heavy drinking days (4 or more drinks/day for women, 5 or more for men) and met 4.5 alcohol withdrawal criteria from the Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition). More gabapentin-treated individuals had no heavy drinking days (12 of 44 participants [27%]) compared with placebo (4 of 46 participants [9%]), a difference of 18.6% (95% CI, 3.1-34.1; P = .02; number needed to treat [NNT], 5.4), and more total abstinence (8 of 44 [18%]) compared with placebo (2 of 46 [4%]), a difference of 13.8% (95% CI, 1.0-26.7; P = .04; NNT, 6.2). The prestudy high-alcohol withdrawal group had positive gabapentin effects on no heavy drinking days (P < .02; NNT, 3.1) and total abstinence (P = .003; NNT, 2.7) compared with placebo, while within the low-alcohol withdrawal group, there were no significant differences. These findings were similar for other drinking variables, where gabapentin was more efficacious than placebo in the high-alcohol withdrawal group only. Gabapentin caused more dizziness, but this did not affect efficacy. CONCLUSIONS AND RELEVANCE These data, combined with others, suggest gabapentin might be most efficacious in people with AUD and a history of alcohol withdrawal symptoms. Future studies should evaluate sleep changes and mood during early recovery as mediators of gabapentin efficacy. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT02349477.
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Affiliation(s)
- Raymond F Anton
- Addiction Sciences Division, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston
| | - Patricia Latham
- Addiction Sciences Division, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston
| | - Konstantin Voronin
- Addiction Sciences Division, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston
| | - Sarah Book
- Addiction Sciences Division, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston
| | - Michaela Hoffman
- Addiction Sciences Division, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston
| | - James Prisciandaro
- Addiction Sciences Division, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston
| | - Emily Bristol
- Addiction Sciences Division, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston
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Abstract
PURPOSE OF REVIEW Gabapentinoids are frequently used in the management of cancer pain. In recent Cochrane systematic reviews, although there was an abundance of evidence relating to non-cancer pain, only a few studies related to cancer pain. This review summarizes recent randomised controlled trials (RCTs) evaluating the use of gabapentinoids for tumour-related (as monotherapy or part of combination therapy) and treatment-related pain. RECENT FINDINGS For tumour-related pain, ten out of thirteen studies showed statistically significant benefits in favour of gabapentinoids. When used, as part of monotherapy or combination therapy, benefits were observed in five out of six studies evaluating gabapentin, and in six out of eight studies evaluating pregabalin. For treatment-related pain, none of the four studies (two gabapentin, two pregabalin) showed statistically significant benefits in favour of gabapentinoids. Unfortunately, many of the studies included were limited by small sample size, lack of blinding, and inadequate follow-up. SUMMARY More and better quality studies are required, although it may be challenging to accomplish in this patient population. Gabapentinoids may offer benefits to cancer patients with pain, but careful titration and monitoring of adverse effects is necessary.
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Alles SRA, Smith PA. Comparison of ex vivo and in vitro actions of gabapentin in superficial dorsal horn and the role of extra-spinal sites of drug action. Neurosci Lett 2019; 694:148-153. [PMID: 30500395 DOI: 10.1016/j.neulet.2018.11.050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 11/23/2018] [Accepted: 11/26/2018] [Indexed: 10/27/2022]
Abstract
Although gabapentin (GBP) is a first-line treatment in the management of neuropathic pain, its mechanism of action is incompletely understood. We have previously shown, in rats made neuropathic following sciatic chronic constriction injury, that IP injection of 100 mg/kg GBP decreases overall excitability of spinal cord slices obtained ex vivo. Excitability was assessed using confocal imaging to monitor the amplitude of K+- induced increases in cytoplasmic Ca2+. This decrease in excitability involved a reduction in the frequency and amplitude of spontaneous EPSC's (sEPSC) in putative excitatory substantia gelatinosa neurons and an increase in sEPSC frequency in putative inhibitory neurons. We used have whole-cell recording to compare these ex vivo actions of GBP with its acute in vitro effects on spinal cord slices obtained from neuropathic but drug-free rats. While GBP (100μM) decreased sEPSC amplitude and frequency in excitatory neurons in vitro in a similar fashion to effects observed ex vivo, sEPSC frequency in inhibitory neurons was decreased in vitro rather than increased. Acute in vitro application of GBP also failed to decrease the overall excitability of slices from neuropathic animals as monitored by confocal Ca2+ imaging. Since spinal cord slices in vitro are disconnected from the periphery and higher brain centres, the GBP-induced increase in sEPSC frequency in inhibitory neurons previously reported and seen ex vivo must result from extra-spinal actions. It may be attributable to alterations in descending neurotrophic control of dorsal horn circuitry.
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Affiliation(s)
- Sascha R A Alles
- Neuroscience and Mental Health Institute and Department of Pharmacology, University of Alberta, Edmonton, AB, T6G 2H7, Canada
| | - Peter A Smith
- Neuroscience and Mental Health Institute and Department of Pharmacology, University of Alberta, Edmonton, AB, T6G 2H7, Canada.
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Hayashida KI, Obata H. Strategies to Treat Chronic Pain and Strengthen Impaired Descending Noradrenergic Inhibitory System. Int J Mol Sci 2019; 20:ijms20040822. [PMID: 30769838 PMCID: PMC6412536 DOI: 10.3390/ijms20040822] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 02/04/2019] [Accepted: 02/12/2019] [Indexed: 12/28/2022] Open
Abstract
Gabapentinoids (gabapentin and pregabalin) and antidepressants (tricyclic antidepressants and serotonin noradrenaline reuptake inhibitors) are often used to treat chronic pain. The descending noradrenergic inhibitory system from the locus coeruleus (LC) to the dorsal horn of the spinal cord plays an important role in the analgesic mechanisms of these drugs. Gabapentinoids activate the LC by inhibiting the release of γ-aminobutyric acid (GABA) and inducing the release of glutamate, thereby increasing noradrenaline levels in the spinal cord. Antidepressants increase noradrenaline levels in the spinal cord by inhibiting reuptake, and accumulating noradrenaline inhibits chronic pain through α2-adrenergic receptors in the spinal cord. Recent animal studies, however, revealed that the function of the descending noradrenergic inhibitory system is impaired in chronic pain states. Other recent studies found that histone deacetylase inhibitors and antidepressants restore the impaired noradrenergic descending inhibitory system acting on noradrenergic neurons in the LC.
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Affiliation(s)
- Ken-Ichiro Hayashida
- Doctorial Course in Medicine, Organ Function-Oriented Medicine, Akita University Graduate School of Medicine;1-1-1, Hondo, Akita-City, Akita 010-8543, Japan.
| | - Hideaki Obata
- Center for Pain Management and Department of Anesthesiology, Fukushima Medical University; 1 Hikarigaoka, Fukushima-City, Fukushima 960-1295, Japan.
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Baldewig M, Goldbaum O, Richter-Landsberg C, Weyland A, Bantel C. Short-term incubation of gabapentin or pregabalin does not affect chemically induced injury in neuronal cell models in vitro. J Pain Res 2018; 11:1181-1190. [PMID: 29950890 PMCID: PMC6016266 DOI: 10.2147/jpr.s162322] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Purpose Gabapentinoids are currently the mainstay of pharmacological treatments for patients with neuropathic pain. Little is known about the effects of this therapy on the integrity of neuronal networks, especially in patients with an already-damaged nervous system. Since gabapentinoids can worsen cognitive functions and recent studies have shown alterations in the brains of patients with neuropathic pain, it may be possible that these drugs have neurotoxic effects. Methods Rat clonal PC12 pheochromocytoma (autonomic) and primary sensory dorsal-root ganglion (DRG) neurons from newborn Wistar rats were employed for this study. To mimic neuronal damage, cells were exposed to cytotoxins using either hydrogen peroxide (H2O2) or vincristine. Results No direct cytotoxic effects were observed after incubating PC12 cells for 24 hours with increasing concentrations of gabapentin or pregabalin using MTT cytotoxicity assays. Even a 7-day incubation did not cause cellular damage. Furthermore, in preinjured PC12 and DRG neurons, neither gabapentin nor pregabalin prevented or enhanced the cytotoxic effects of H2O2 or vincristine after incubation for 24 hours and 7 days, respectively. Cell morphology and integrity of the cytoskeleton assessed by employing immunostaining of cytoskeletal proteins (α-tubulin, neurofilament L) remained intact and were not altered by gabapentinoids. Conclusion Based on these results, gabapentinoids are unlikely to be neurotoxic in cultured autonomic (PC12) and sensory DRG cells, even when cells are preinjured. These results are of high clinical relevance, as it seems unlikely that the morphological changes recently observed in the brains of neuropathic pain patients are caused or worsened by gabapentinoids.
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Affiliation(s)
- Malte Baldewig
- Department of Anesthesiology, Klinikum Oldenburg, Oldenburg, Germany
| | - Olaf Goldbaum
- Molecular Neurobiology, Department of Neuroscience, University of Oldenburg, Oldenburg, Germany
| | | | - Andreas Weyland
- Department of Anesthesiology, Klinikum Oldenburg, Oldenburg, Germany
| | - Carsten Bantel
- Department of Anesthesiology, Klinikum Oldenburg, Oldenburg, Germany
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Hayashida KI, Kimuram M, Eisenach JC. Blockade of α2-adrenergic or metabotropic glutamate receptors induces glutamate release in the locus coeruleus to activate descending inhibition in rats with chronic neuropathic hypersensitivity. Neurosci Lett 2018; 676:41-45. [PMID: 29627342 DOI: 10.1016/j.neulet.2018.04.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 04/03/2018] [Accepted: 04/03/2018] [Indexed: 10/17/2022]
Abstract
Locus coeruleus (LC)-spinal noradrenergic projections are important to endogenous analgesic mechanisms and can be activated by local glutamate signaling in the LC. The current study examined the local glutamatergic, GABAergic, and noradrenergic influences on glutamate release in the LC and noradrenergic descending inhibition in rats 6 weeks after spinal nerve ligation (SNL). Intra-LC injection of the α2 adrenoceptor antagonist idazoxan or the group 2 metabotropic glutamate receptor (mGluR) antagonist (RS)-α-Methyl-4-tetrazolylphenylglycine (MTPG) increased withdrawal thresholds in SNL animals and this was reversed by the blockade of α-amino-3-hydroxy-5-methyl- 4-isoxazolepropionic acid (AMPA) receptors in the LC or α2-adrenoceptors in the spinal cord, but not in normal animals. Neither blockade of GABA-A nor GABA-B receptors in the LC affected withdrawal thresholds in normal and SNL animals. Intra-LC perfusion of idazoxan increased extracellular glutamate in the LC in SNL animals but not in normal animals. Intra-LC perfusion of MTPG increased extracellular glutamate in the LC in both normal and SNL animals. These results suggest that local noradrenaline and glutamate tonically inhibit glutamate release in the LC after peripheral nerve injury and this may contribute to reduced descending inhibition in response to noxious input during chronic neuropathic pain.
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Affiliation(s)
- Ken-Ichiro Hayashida
- Department of Neurophysiology, Akita University School of Medicine, Akita, 010-8543, Japan; Pain Mechanisms Laboratory, Department of Anesthesiology, Wake Forest School of Medicine, Winston Salem, NC, 27157, USA.
| | - Masafumi Kimuram
- Pain Mechanisms Laboratory, Department of Anesthesiology, Wake Forest School of Medicine, Winston Salem, NC, 27157, USA
| | - James C Eisenach
- Pain Mechanisms Laboratory, Department of Anesthesiology, Wake Forest School of Medicine, Winston Salem, NC, 27157, USA
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Descending Noradrenergic Inhibition: An Important Mechanism of Gabapentin Analgesia in Neuropathic Pain. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1099:93-100. [DOI: 10.1007/978-981-13-1756-9_8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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19
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Abstract
Abstract Neuropathic pain, comprising a range of heterogeneous conditions, is often severe and difficult to manage, and this may result in a chronic condition that negatively affects the overall functioning and quality of life in patients. The pharmacotherapy of neuropathic pain is challenging and for many patients effective treatment is lacking; therefore, evidence-based recommendations are essential. Currently, there is general agreement on which drugs are appropriate for the first-line treatment of neuropathic pain, whereas debate continues regarding second- and third-line treatments. First-line drugs for neuropathic pain include antidepressants (tricyclic antidepressants and serotonin–noradrenaline reuptake inhibitors) and anticonvulsants acting at calcium channels (pregabalin and gabapentin). Second- and third-line drugs for neuropathic pain include topical lidocaine and opioids. Although efficacious in the treatment of neuropathic pain, opioids are not considered to be a first choice because of adverse drug reactions and, more recently, because of concerns about abuse, diversion, and addiction. A clear understanding of the mechanism of action of currently available drugs is an essential step towards an effective clinical approach that aims to tailor therapies both to the specific neuropathic disease and to the needs of an individual patient. This review provides an overview of current drugs available for the treatment of neuropathic pain with an emphasis on their mechanism of action. Funding Pfizer, Italy.
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Excessive spinal glutamate transmission is involved in oxaliplatin-induced mechanical allodynia: a possibility for riluzole as a prophylactic drug. Sci Rep 2017; 7:9661. [PMID: 28851920 PMCID: PMC5574967 DOI: 10.1038/s41598-017-08891-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 07/14/2017] [Indexed: 12/27/2022] Open
Abstract
Oxaliplatin, a chemotherapy medication, causes severe peripheral neuropathy. Although oxaliplatin-induced peripheral neuropathy is a dose-limiting toxicity, a therapeutic strategy against its effects has not been established. We previously reported the involvement of N-methyl-D-aspartate receptors and their intracellular signalling pathway in oxaliplatin-induced mechanical allodynia in rats. The aim of this study was to clarify the involvement of spinal glutamate transmission in oxaliplatin-induced mechanical allodynia. In vivo spinal microdialysis revealed that the baseline glutamate concentration was elevated in oxaliplatin-treated rats, and that mechanical stimulation of the hind paw markedly increased extracellular glutamate concentration in the same rats. In these rats, the expression of glutamate transporter 1 (GLT-1), which plays a major role in glutamate uptake, was decreased in the spinal cord. Moreover, we explored the potential of pharmacological therapy targeting maintenance of extracellular glutamate homeostasis. The administration of riluzole, an approved drug for amyotrophic lateral sclerosis, suppressed the increase of glutamate concentration, the decrease of GLT-1 expression and the development of mechanical allodynia. These results suggest that oxaliplatin disrupts the extracellular glutamate homeostasis in the spinal cord, which may result in neuropathic symptoms, and support the use of riluzole for prophylaxis of oxaliplatin-induced mechanical allodynia.
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Corona-Ramos JN, Déciga-Campos M, Romero-Piña M, Medina LA, Martínez-Racine I, Jaramillo-Morales OA, García-López P, López-Muñoz FJ. The Effect of Gabapentin and Tramadol in Cancer Pain Induced by Glioma Cell in Rat Femur. Drug Dev Res 2017; 78:173-183. [PMID: 28593649 DOI: 10.1002/ddr.21389] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 05/19/2017] [Indexed: 12/30/2022]
Abstract
Preclinical Research The presence of pain as part of the cancer process is variable. Glioblastoma multiform (GBM) can produce bone metastasis, a condition that involves other pathological phenotypes including neuropathic and inflammatory pain. Tramadol and gabapentin are drugs used in the treatment of neuropathic pain. However, there are no studies evaluating their analgesic effects in bone metastasis. We produced a pain model induced by the inoculation of glioma cells (105 ) into the rat femur, by perforating the intercodiloid fossa. Painful behavior was evaluated by measuring mechanical allodynia using the Von Frey test while thermal hyperalgesia was assessed in the plantar test. Histopathological features were evaluated and antinociceptive responses were compared using tramadol and gabapentin. The inoculation of cells inside the right femur produced nociceptive behaviors. Tramadol and gabapentin produced an anti-allodynic effect in this condition, but tramadol did not produce an anti-hyperalgesic response. The development of this model will allow us to perform tests to elucidate the pathology of bone metastasis, cancer pain, and in particular the pain produced by glioma. Drug Dev Res 78 : 173-183, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
| | - Myrna Déciga-Campos
- Sección de Estudios de Posgrado e Investigación de la Escuela Superior de Medicina del IPN, C.P. 11340, México, D.F, México
| | - Mario Romero-Piña
- Departamento de Imagenología, Instituto Nacional de Cancerología, C.P. 14080, México, D.F, México
| | - Luis A Medina
- Instituto de Física, Universidad Nacional Autónoma de México/Unidad de Investigación Biomédica en Cáncer INCan-UNAM, C.P. 14080, México, D.F., México
| | - Issac Martínez-Racine
- Departamento de Patología, Facultad de Medicina Veterinaria y Zootecnia, UNAM, Ciudad de México, 04510, México
| | - Osmar A Jaramillo-Morales
- Departamento de Farmacobiología, Cinvestav-Sede Sur, C.P. 14330, Delegación Tlálpan, México, D.F, México
| | - Patricia García-López
- Laboratorio de Farmacología, Subdirección de Investigación Básica, Instituto Nacional de Cancerología, C.P. 14080, México, D.F, México
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Houghton KT, Forrest A, Awad A, Atkinson LZ, Stockton S, Harrison PJ, Geddes JR, Cipriani A. Biological rationale and potential clinical use of gabapentin and pregabalin in bipolar disorder, insomnia and anxiety: protocol for a systematic review and meta-analysis. BMJ Open 2017; 7:e013433. [PMID: 28348186 PMCID: PMC5372050 DOI: 10.1136/bmjopen-2016-013433] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
INTRODUCTION Gabapentin has been extensively prescribed off-label for psychiatric indications, with little established evidence of efficacy. Gabapentin and pregabalin, a very similar drug with the same mechanism of action, bind to a subunit of voltage-dependent calcium channels which are implicated in the aetiopathogenesis of bipolar disorder, anxiety and insomnia. This systematic review and meta-analysis aims to collect and critically appraise all the available evidence about the efficacy and tolerability of gabapentin and pregabalin in the treatment of bipolar disorder, insomnia and anxiety. METHODS AND ANALYSIS We will include all randomised controlled trials (RCTs) reported as double-blind and comparing gabapentin or pregabalin with placebo or any other active pharmacological treatment (any preparation, dose, frequency, route of delivery or setting) in patients with bipolar disorder, anxiety or insomnia. For consideration of adverse effects (tolerability), single-blind or open-label RCTs and non-randomised evidence will also be summarised. The main outcomes will be efficacy (measured as dichotomous and continuous outcome) and acceptability (proportion of patients who dropped out of the allocated treatment). Published and unpublished studies will be sought through relevant database searches, trial registries and websites; all reference selection and data extraction will be conducted by at least 2 independent reviewers. We will conduct a random-effects meta-analysis to synthesise all evidence for each outcome. Heterogeneity between studies will be investigated by the I2 statistic. Data from included studies will be entered into a funnel plot for investigation of small-study effects. No subgroup analysis will be undertaken, but we will carry out sensitivity analyses about combination treatment, psychiatric comorbidity, use of rescue medications and fixed versus random-effects model. ETHICS AND DISSEMINATION This review does not require ethical approval. This protocol has been registered on PROSPERO (CRD42016041802). The results of the systematic review will be disseminated via publication in a peer-reviewed journal.
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Affiliation(s)
- Kerensa T Houghton
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, UK
| | - Alexandra Forrest
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford OX3 7JX, UK
| | - Amine Awad
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, UK
| | - Lauren Z Atkinson
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, UK
| | - Sarah Stockton
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, UK
| | - Paul J Harrison
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford OX3 7JX, UK
| | - John R Geddes
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford OX3 7JX, UK
| | - Andrea Cipriani
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, UK
- Oxford Health NHS Foundation Trust, Warneford Hospital, Oxford OX3 7JX, UK
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Boadas-Vaello P, Homs J, Reina F, Carrera A, Verdú E. Neuroplasticity of Supraspinal Structures Associated with Pathological Pain. Anat Rec (Hoboken) 2017; 300:1481-1501. [PMID: 28263454 DOI: 10.1002/ar.23587] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 09/27/2016] [Accepted: 10/18/2016] [Indexed: 12/19/2022]
Abstract
Peripheral nerve and spinal cord injuries, along with other painful syndromes such as fibromyalgia, diabetic neuropathy, chemotherapeutic neuropathy, trigeminal neuralgia, complex regional pain syndrome, and/or irritable bowel syndrome, cause several neuroplasticity changes in the nervous system along its entire axis affecting the different neuronal nuclei. This paper reviews these changes, focusing on the supraspinal structures that are involved in the modulation and processing of pain, including the periaqueductal gray matter, red nucleus, locus coeruleus, rostral ventromedial medulla, thalamus, hypothalamus, basal ganglia, cerebellum, habenula, primary, and secondary somatosensory cortex, motor cortex, mammillary bodies, hippocampus, septum, amygdala, cingulated, and prefrontal cortex. Hyperexcitability caused by the modification of postsynaptic receptor expression, central sensitization, and potentiation of presynaptic delivery of neurotransmitters, as well as the reduction of inhibitory inputs, changes in dendritic spine, neural circuit remodeling, alteration of gray matter, and upregulation of proinflammatory mediators (e.g., cytokines) by reactivation of astrocytes and microglial cells are the main functional, structural, and molecular neuroplasticity changes observed in the above supraspinal structures, associated with pathological pain. Studying these changes in greater depth may lead to the implementation and improvement of new therapeutic strategies against pathological pain. Anat Rec, 300:1481-1501, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Pere Boadas-Vaello
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Faculty of Medicine, Universitat de Girona, Girona, Catalonia, 17003, Spain
| | - Judit Homs
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Faculty of Medicine, Universitat de Girona, Girona, Catalonia, 17003, Spain.,Department of Physical Therapy EUSES-Universitat of Girona, Salt (Girona), Catalonia, 17190, Spain
| | - Francisco Reina
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Faculty of Medicine, Universitat de Girona, Girona, Catalonia, 17003, Spain
| | - Ana Carrera
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Faculty of Medicine, Universitat de Girona, Girona, Catalonia, 17003, Spain
| | - Enrique Verdú
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Faculty of Medicine, Universitat de Girona, Girona, Catalonia, 17003, Spain
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Chenaf C, Chapuy E, Libert F, Marchand F, Courteix C, Bertrand M, Gabriel C, Mocaër E, Eschalier A, Authier N. Agomelatine: a new opportunity to reduce neuropathic pain-preclinical evidence. Pain 2017; 158:149-160. [PMID: 27984527 DOI: 10.1097/j.pain.0000000000000738] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Antidepressants are first-line treatments of neuropathic pain but not all these drugs are really effective. Agomelatine is an antidepressant with a novel mode of action, acting as an MT1/MT2 melatonergic receptor agonist and a 5-HT2C receptor antagonist that involves indirect norepinephrine release. Melatonin, serotonin, and norepinephrine have been involved in the pathophysiology of neuropathic pain. Yet, no study has been conducted to determine agomelatine effects on neuropathic pain in animal models. Using 3 rat models of neuropathic pain of toxic (oxaliplatin/OXA), metabolic (streptozocin/STZ), and traumatic (sciatic nerve ligation/CCI [chronic constriction nerve injury]) etiologies, we investigated the antihypersensitivity effect of acute and repeated agomelatine administration. We then determined the influence of melatonergic, 5-HT2C, α-2 and β-1/2 adrenergic receptor antagonists in the antihypersensitivity effect of agomelatine. The effect of the combination of agomelatine + gabapentin was evaluated using an isobolographic approach. In STZ and CCI models, single doses of agomelatine significantly and dose dependently reduced mechanical hypersensitivity. After daily administrations for 2 weeks, this effect was confirmed in the CCI model and agomelatine also displayed a marked antihypersensitivity effect in the OXA model. The antihypersensitivity effect of agomelatine involved melatonergic, 5-HT2C, and α-2 adrenergic receptors but not beta adrenoceptors. The isobolographic analysis demonstrated that the combination of agomelatine + gabapentin had additive effects. Agomelatine exerts a clear-cut antihypersensitivity effect in 3 different neuropathic pain models. Its effect is mediated by melatonergic and 5-HT2C receptors and, although agomelatine has no affinity, also by α-2 adrenergic receptors. Finally, agomelatine combined with gabapentin produces an additive antihypersensitivity effect.
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Affiliation(s)
- Chouki Chenaf
- Université Clermont Auvergne, Université d'Auvergne, INSERM UMR 1107 Neuro-Dol Equipe Pharmacologie Fondamentale et Clinique de la Douleur, CHU Clermont-Ferrand Service de Pharmacologie Médicale, Institut Analgesia, Faculté de Médecine, Clermont-Ferrand, France
| | - Eric Chapuy
- Université Clermont Auvergne, Université d'Auvergne, INSERM UMR 1107 Neuro-Dol Equipe Pharmacologie Fondamentale et Clinique de la Douleur, Institut Analgesia, Faculté de Médecine, Clermont-Ferrand, France
| | - Frédéric Libert
- Université Clermont Auvergne, Université d'Auvergne, INSERM UMR 1107 Neuro-Dol Equipe Pharmacologie Fondamentale et Clinique de la Douleur, CHU Clermont-Ferrand Service de Pharmacologie Médicale, Institut Analgesia, Faculté de Médecine, Clermont-Ferrand, France
| | - Fabien Marchand
- Université Clermont Auvergne, Université d'Auvergne, INSERM UMR 1107 Neuro-Dol Equipe Pharmacologie Fondamentale et Clinique de la Douleur, Institut Analgesia, Faculté de Médecine, Clermont-Ferrand, France
| | - Christine Courteix
- Université Clermont Auvergne, Université d'Auvergne, INSERM UMR 1107 Neuro-Dol Equipe Pharmacologie Fondamentale et Clinique de la Douleur, Institut Analgesia, Faculté de Médecine, Clermont-Ferrand, France
| | - Marianne Bertrand
- Neuropsychiatry Division, Institut de Recherches Internationales Servier, Suresnes, France
| | - Cecilia Gabriel
- Neuropsychiatry Division, Institut de Recherches Internationales Servier, Suresnes, France
| | - Elisabeth Mocaër
- Neuropsychiatry Division, Institut de Recherches Internationales Servier, Suresnes, France
| | - Alain Eschalier
- Université Clermont Auvergne, Université d'Auvergne, INSERM UMR 1107 Neuro-Dol Equipe Pharmacologie Fondamentale et Clinique de la Douleur, CHU Clermont-Ferrand Service de Pharmacologie Médicale, Institut Analgesia, Faculté de Médecine, Clermont-Ferrand, France
| | - Nicolas Authier
- Université Clermont Auvergne, Université d'Auvergne, INSERM UMR 1107 Neuro-Dol Equipe Pharmacologie Fondamentale et Clinique de la Douleur, CHU Clermont-Ferrand Service de Pharmacologie Médicale, Institut Analgesia, Faculté de Médecine, Clermont-Ferrand, France
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Taylor BK, Westlund KN. The noradrenergic locus coeruleus as a chronic pain generator. J Neurosci Res 2016; 95:1336-1346. [PMID: 27685982 DOI: 10.1002/jnr.23956] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 08/25/2016] [Accepted: 09/07/2016] [Indexed: 12/17/2022]
Abstract
Central noradrenergic centers such as the locus coeruleus (LC) are traditionally viewed as pain inhibitory; however, complex interactions among brainstem pathways and their receptors modulate both inhibition and facilitation of pain. In addition to the well-described role of descending pontospinal pathways that inhibit spinal nociceptive transmission, an emerging body of research now indicates that noradrenergic neurons in the LC and their terminals in the dorsal reticular nucleus (DRt), medial prefrontal cortex (mPFC), spinal dorsal horn, and spinal trigeminal nucleus caudalis participate in the development and maintenance of allodynia and hyperalgesia after nerve injury. With time after injury, we argue that the balance of LC function shifts from pain inhibition to pain facilitation. Thus, the pain-inhibitory actions of antidepressant drugs achieved with elevated noradrenaline concentrations in the dorsal horn may be countered or even superseded by simultaneous activation of supraspinal facilitating systems dependent on α1 -adrenoreceptors in the DRt and mPFC as well as α2 -adrenoreceptors in the LC. Indeed, these opposing actions may account in part for the limited treatment efficacy of tricyclic antidepressants and noradrenaline reuptake inhibitors such as duloxetine for the treatment of chronic pain. We propose that the traditional view of the LC as a pain-inhibitory structure be modified to account for its capacity as a pain facilitator. Future studies are needed to determine the neurobiology of ascending and descending pathways and the pharmacology of receptors underlying LC-mediated pain inhibition and facilitation. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Bradley K Taylor
- Department of Physiology, School of Medicine, University of Kentucky Medical Center, Lexington, Kentucky
| | - Karin N Westlund
- Department of Physiology, School of Medicine, University of Kentucky Medical Center, Lexington, Kentucky
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Kaushal R, Taylor BK, Jamal AB, Zhang L, Ma F, Donahue R, Westlund KN. GABA-A receptor activity in the noradrenergic locus coeruleus drives trigeminal neuropathic pain in the rat; contribution of NAα1 receptors in the medial prefrontal cortex. Neuroscience 2016; 334:148-159. [PMID: 27520081 DOI: 10.1016/j.neuroscience.2016.08.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 07/20/2016] [Accepted: 08/03/2016] [Indexed: 12/24/2022]
Abstract
Trigeminal neuropathic pain is described as constant excruciating facial pain. The study goal was to investigate the role of nucleus locus coeruleus (LC) in a model of chronic orofacial neuropathic pain (CCI-ION). The study examines LC's relationship to both the medullary dorsal horn receiving trigeminal nerve sensory innervation and the medial prefrontal cortex (mPFC). LC is a major source of CNS noradrenaline (NA) and a primary nucleus involved in pain modulation. Although descending inhibition of acute pain by LC is well established, contribution of the LC to facilitation of chronic neuropathic pain is also reported. In the present study, a rat orofacial pain model of trigeminal neuropathy was induced by chronic constrictive injury of the infraorbital nerve (CCI-ION). Orofacial neuropathic pain was indicated by development of whisker pad mechanical hypersensitivity. Hypersensitivity was alleviated by selective elimination of NA neurons, including LC (A6 cell group), with the neurotoxin anti-dopamine-β-hydroxylase saporin (anti-DβH-saporin) microinjected either intracerebroventricularly (i.c.v.) or into trigeminal spinal nucleus caudalis (spVc). The GABAA receptor antagonist, bicuculline, administered directly into LC (week 8) inhibited hypersensitivity. This indicates a valence shift in which increased GABAA signaling ongoing in LC after trigeminal nerve injury paradoxically produces excitatory facilitation of the chronic pain state. Microinjection of NAα1 receptor antagonist, benoxathian, into mPFC attenuated whisker pad hypersensitivity, while NAα2 receptor antagonist, idazoxan, was ineffective. Thus, GABAA-mediated activation of NA neurons during CCI-ION can facilitate hypersensitivity through NAα1 receptors in the mPFC. These data indicate LC is a chronic pain generator.
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Affiliation(s)
- R Kaushal
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536-0298, United States
| | - B K Taylor
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536-0298, United States
| | - A B Jamal
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536-0298, United States
| | - L Zhang
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536-0298, United States
| | - F Ma
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536-0298, United States
| | - R Donahue
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536-0298, United States
| | - K N Westlund
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536-0298, United States.
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Kremer M, Salvat E, Muller A, Yalcin I, Barrot M. Antidepressants and gabapentinoids in neuropathic pain: Mechanistic insights. Neuroscience 2016; 338:183-206. [PMID: 27401055 DOI: 10.1016/j.neuroscience.2016.06.057] [Citation(s) in RCA: 158] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 06/21/2016] [Accepted: 06/30/2016] [Indexed: 01/20/2023]
Abstract
Neuropathic pain arises as a consequence of a lesion or disease affecting the somatosensory system. It is generally chronic and challenging to treat. The recommended pharmacotherapy for neuropathic pain includes the use of some antidepressants, such as tricyclic antidepressants (TCAs) (amitriptyline…) or serotonin and noradrenaline re-uptake inhibitors (duloxetine…), and/or anticonvulsants such as the gabapentinoids gabapentin or pregabalin. Antidepressant drugs are not acute analgesics but require a chronic treatment to relieve neuropathic pain, which suggests the recruitment of secondary downstream mechanisms as well as long-term molecular and neuronal plasticity. Noradrenaline is a major actor for the action of antidepressant drugs in a neuropathic pain context. Mechanistic hypotheses have implied the recruitment of noradrenergic descending pathways as well as the peripheral recruitment of noradrenaline from sympathetic fibers sprouting into dorsal root ganglia; and importance of both α2 and β2 adrenoceptors have been reported. These monoamine re-uptake inhibitors may also indirectly act as anti-proinflammatory cytokine drugs; and their therapeutic action requires the opioid system, particularly the mu (MOP) and/or delta (DOP) opioid receptors. Gabapentinoids, which target the voltage-dependent calcium channels α2δ-1 subunit, inhibit calcium currents, thus decreasing the excitatory transmitter release and spinal sensitization. Gabapentinoids also activate the descending noradrenergic pain inhibitory system coupled to spinal α2 adrenoceptors. Gabapentinoid treatment may also indirectly impact on neuroimmune actors, like proinflammatory cytokines. These drugs are effective against neuropathic pain both with acute administration at high dose and with repeated administration. This review focuses on mechanistic knowledge concerning chronic antidepressant treatment and gabapentinoid treatment in a neuropathic pain context.
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Affiliation(s)
- Mélanie Kremer
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique, Strasbourg, France; Université de Strasbourg, Strasbourg, France
| | - Eric Salvat
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique, Strasbourg, France; Centre d'Etude et de Traitement de la Douleur, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - André Muller
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique, Strasbourg, France; Centre d'Etude et de Traitement de la Douleur, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Ipek Yalcin
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique, Strasbourg, France
| | - Michel Barrot
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique, Strasbourg, France.
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Corona-Ramos JN, De la O-Arciniega M, Déciga-Campos M, Medina-López JR, Domínguez-Ramírez AM, Jaramillo-Morales OA, Espinosa-Juárez JV, López-Muñoz FJ. The Antinociceptive Effects of Tramadol and/or Gabapentin on Rat Neuropathic Pain Induced by a Chronic Constriction Injury. Drug Dev Res 2016; 77:217-26. [DOI: 10.1002/ddr.21313] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 05/07/2016] [Indexed: 01/17/2023]
Affiliation(s)
| | - Minarda De la O-Arciniega
- Área Académica de Farmacia del Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo; Pachuca Hidalgo México
| | - Myrna Déciga-Campos
- Sección de Estudios de Posgrado e Investigación de la Escuela Superior de Medicina del IPN; C.P. 11340 México D.F. México
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Abstract
Patients with chronic pain can be challenging to manage and historically providers have relied on opiates to treat pain. Recent studies have brought into question the safety and efficacy of chronic opiate therapy in the noncancer population. There is a vast amount of literature to support the use of nonsteroidal anti-inflammatory medications, antidepressants, anticonvulsants, topical agents, cannabinoids, and botulinum toxin either in conjunction with or in lieu of opioids. Intrathecal drug delivery systems can deliver some of these medications directly to their primary site of action while minimizing the side effects seen with systemic administration.
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Affiliation(s)
- Benjamin R Beal
- Division of Pain Medicine, Department of Anesthesiology, University of California, San Diego, San Diego, CA, USA
| | - Mark S Wallace
- Division of Pain Medicine, Department of Anesthesiology, University of California, San Diego, San Diego, CA, USA.
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Carcamo CR. Bimodal Modulation of Ipsilateral Spinal-Coeruleo-Spinal Pathway in CRPS: A Novel Model for Explaining Different Clinical Features of the Syndrome. PAIN MEDICINE 2015; 16:1589-96. [PMID: 26058872 DOI: 10.1111/pme.12733] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The objective is to present a hypothesis to explain the sensory, autonomic, and motor disturbances associated with complex regional pain syndrome (CRPS) syndrome. METHODS The author reviewed the available and relevant literature, which was supplemented with research on experimental animal models, with a focus on how they may translate into humans, particularly in areas about pathophysiologic mechanisms of CRPS. RESULTS We propose that different CRPS subtypes may result from facilitative or inhibitory influences exerted by the spinal-coeruleo-spinal pathway in three sites at the spinal cord: the dorsal horn (DH), intermediolateral cell column (IML) and ventral horn (VH). A facilitatory influence over DH may have a pronociceptive effect that explains exacerbated pain, sensory disturbances, and spreading sensitization and neuroinflammation. Conversely, a facilitatory influence over preganglionic neurons located in IML cell column may increase sympathetic outflow with peripheral vasoconstriction, which leads to cold skin, ipsilateral limb ischaemia, and sympathetically maintained pain (SMP). For patients presenting with these symptoms, a descending inhibitory influence would be predicted to result in decreased sympathetic outflow and warm skin, as well as impairment of peripheral vasoconstrictor reflexes. Finally, a descending inhibitory influence over VH could explain muscle weakness and decreased active range of motion, while also facilitating motor reflexes, tremor and dystonia. CONCLUSIONS The proposed model provides a mechanistically based diagnostic scheme for classifying and explaining the sensory, autonomic and motor disturbances associated with CRPS syndrome.
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Affiliation(s)
- Cesar R Carcamo
- Chronic Pain Unit, Mutual de Seguridad Hospital, Santiago, Chile
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31
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Stoicea N, Russell D, Weidner G, Durda M, Joseph NC, Yu J, Bergese SD. Opioid-induced hyperalgesia in chronic pain patients and the mitigating effects of gabapentin. Front Pharmacol 2015; 6:104. [PMID: 26074817 PMCID: PMC4444749 DOI: 10.3389/fphar.2015.00104] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 04/28/2015] [Indexed: 12/22/2022] Open
Abstract
Chronic pain patients receiving opioid drugs are at risk for opioid-induced hyperalgesia (OIH), wherein opioid pain medication leads to a paradoxical pain state. OIH involves central sensitization of primary and secondary afferent neurons in the dorsal horn and dorsal root ganglion, similar to neuropathic pain. Gabapentin, a gamma-aminobutyric acid (GABA) analog anticonvulsant used to treat neuropathic pain, has been shown in animal models to reduce fentanyl hyperalgesia without compromising analgesic effect. Chronic pain patients have also exhibited lower opioid consumption and improved pain response when given gabapentin. However, few human studies investigating gabapentin use in OIH have been performed in recent years. In this review, we discuss the potential mechanisms that underlie OIH and provide a critical overview of interventional therapeutic strategies, especially the clinically-successful drug gabapentin, which may reduce OIH.
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Affiliation(s)
- Nicoleta Stoicea
- Department of Anesthesiology, The Ohio State University Wexner Medical Center Columbus, OH, USA
| | - Daric Russell
- Department of Anesthesiology, The Ohio State University Wexner Medical Center Columbus, OH, USA
| | - Greg Weidner
- Department of Anesthesiology, The Ohio State University Wexner Medical Center Columbus, OH, USA
| | - Michael Durda
- Department of Anesthesiology, The Ohio State University Wexner Medical Center Columbus, OH, USA
| | - Nicholas C Joseph
- Department of Neuroscience, The Ohio State University Columbus, OH, USA
| | - Jeffrey Yu
- Medical School, The Ohio State University College of Medicine Columbus, OH, USA
| | - Sergio D Bergese
- Department of Anesthesiology, The Ohio State University Wexner Medical Center Columbus, OH, USA ; Department of Neurological Surgery, The Ohio State University Wexner Medical Center Columbus, OH, USA
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32
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Abstract
Inhibition of both itching and scratching is important in the treatment of chronic pruritic diseases, because itching has a negative impact on quality of life and vigorous scratching worsens skin conditions. Pharmacological modulation of itch transmission in the dorsal horn is an effective way to inhibit both itching and scratching in pruritic diseases. Pruriceptive transmission in the spinal dorsal horn undergoes inhibitory modulation by the descending noradrenergic system. The noradrenergic inhibition is mediated by excitatory α₁-adrenoceptors located on inhibitory interneurons and inhibitory α₂-adrenoceptors located on central terminals of primary sensory neurons. The descending noradrenergic system and α-adrenoceptors in the dorsal horn are potential targets for antipruritic drugs.
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Affiliation(s)
- Yasushi Kuraishi
- Laboratory of Applied Pharmacology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama, 930-0194, Japan,
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33
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Hirsch S, Dickenson A, Corradini L. Anesthesia influences neuronal activity and drug effectiveness in neuropathic rats. Pain 2014; 155:2583-2590. [DOI: 10.1016/j.pain.2014.09.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 09/16/2014] [Accepted: 09/16/2014] [Indexed: 01/16/2023]
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Oginsky MF, Cui N, Zhong W, Johnson CM, Jiang C. Alterations in the cholinergic system of brain stem neurons in a mouse model of Rett syndrome. Am J Physiol Cell Physiol 2014; 307:C508-20. [PMID: 25009110 DOI: 10.1152/ajpcell.00035.2014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Rett syndrome is an autism-spectrum disorder resulting from mutations to the X-linked gene, methyl-CpG binding protein 2 (MeCP2), which causes abnormalities in many systems. It is possible that the body may develop certain compensatory mechanisms to alleviate the abnormalities. The norepinephrine system originating mainly in the locus coeruleus (LC) is defective in Rett syndrome and Mecp2-null mice. LC neurons are subject to modulation by GABA, glutamate, and acetylcholine (ACh), providing an ideal system to test the compensatory hypothesis. Here we show evidence for potential compensatory modulation of LC neurons by post- and presynaptic ACh inputs. We found that the postsynaptic currents of nicotinic ACh receptors (nAChR) were smaller in amplitude and longer in decay time in the Mecp2-null mice than in the wild type. Single-cell PCR analysis showed a decrease in the expression of α3-, α4-, α7-, and β3-subunits and an increase in the α5- and α6-subunits in the mutant mice. The α5-subunit was present in many of the LC neurons with slow-decay nAChR currents. The nicotinic modulation of spontaneous GABAA-ergic inhibitory postsynaptic currents in LC neurons was enhanced in Mecp2-null mice. In contrast, the nAChR manipulation of glutamatergic input to LC neurons was unaffected in both groups of mice. Our current-clamp studies showed that the modulation of LC neurons by ACh input was reduced moderately in Mecp2-null mice, despite the major decrease in nAChR currents, suggesting possible compensatory processes may take place, thus reducing the defects to a lesser extent in LC neurons.
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Affiliation(s)
- Max F Oginsky
- Department of Biology, Georgia State University, Atlanta, Georgia
| | - Ningren Cui
- Department of Biology, Georgia State University, Atlanta, Georgia
| | - Weiwei Zhong
- Department of Biology, Georgia State University, Atlanta, Georgia
| | | | - Chun Jiang
- Department of Biology, Georgia State University, Atlanta, Georgia
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35
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Percie du Sert N, Rice ASC. Improving the translation of analgesic drugs to the clinic: animal models of neuropathic pain. Br J Pharmacol 2014; 171:2951-63. [PMID: 24527763 PMCID: PMC4055199 DOI: 10.1111/bph.12645] [Citation(s) in RCA: 140] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 01/30/2014] [Accepted: 02/10/2014] [Indexed: 12/17/2022] Open
Abstract
Neuropathic pain remains an area of considerable unmet clinical need. Research based on preclinical animal models has failed to deliver truly novel treatment options, questioning the predictive value of these models. This review addresses the shortcomings of rodent in vivo models commonly used in the field and highlights approaches which could increase their predictivity, including more clinically relevant assays, outcome measures and animal characteristics. The methodological quality of animal studies also needs to be improved. Low internal validity and incomplete reporting lead to a waste of valuable research resources and animal lives, and ultimately prevent an objective assessment of the true predictivity of in vivo models.
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Affiliation(s)
- N Percie du Sert
- National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), London, UK
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36
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Vinik A, Emir B, Parsons B, Cheung R. Prediction of Pregabalin-Mediated Pain Response by Severity of Sleep Disturbance in Patients with Painful Diabetic Neuropathy and Post-Herpetic Neuralgia. PAIN MEDICINE 2014; 15:661-70. [DOI: 10.1111/pme.12310] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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37
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Alyautdin R, Khalin I, Nafeeza MI, Haron MH, Kuznetsov D. Nanoscale drug delivery systems and the blood-brain barrier. Int J Nanomedicine 2014; 9:795-811. [PMID: 24550672 PMCID: PMC3926460 DOI: 10.2147/ijn.s52236] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The protective properties of the blood–brain barrier (BBB) are conferred by the intricate architecture of its endothelium coupled with multiple specific transport systems expressed on the surface of endothelial cells (ECs) in the brain’s vasculature. When the stringent control of the BBB is disrupted, such as following EC damage, substances that are safe for peripheral tissues but toxic to neurons have easier access to the central nervous system (CNS). As a consequence, CNS disorders, including degenerative diseases, can occur independently of an individual’s age. Although the BBB is crucial in regulating the biochemical environment that is essential for maintaining neuronal integrity, it limits drug delivery to the CNS. This makes it difficult to deliver beneficial drugs across the BBB while preventing the passage of potential neurotoxins. Available options include transport of drugs across the ECs through traversing occludins and claudins in the tight junctions or by attaching drugs to one of the existing transport systems. Either way, access must specifically allow only the passage of a particular drug. In general, the BBB allows small molecules to enter the CNS; however, most drugs with the potential to treat neurological disorders other than infections have large structures. Several mechanisms, such as modifications of the built-in pumping-out system of drugs and utilization of nanocarriers and liposomes, are among the drug-delivery systems that have been tested; however, each has its limitations and constraints. This review comprehensively discusses the functional morphology of the BBB and the challenges that must be overcome by drug-delivery systems and elaborates on the potential targets, mechanisms, and formulations to improve drug delivery to the CNS.
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Affiliation(s)
- Renad Alyautdin
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Sungai Buloh, Selangor, Malaysia
| | - Igor Khalin
- Faculty of Medicine and Defence Health, National Defence University of Malaysia (NDUM), Kuala Lumpur, Malaysia
| | - Mohd Ismail Nafeeza
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Sungai Buloh, Selangor, Malaysia
| | | | - Dmitry Kuznetsov
- Department of Medicinal Nanobiotechnologies, N. I. Pirogoff Russian State Medical University, Moscow, Russia
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Suto T, Severino AL, Eisenach JC, Hayashida KI. Gabapentin increases extracellular glutamatergic level in the locus coeruleus via astroglial glutamate transporter-dependent mechanisms. Neuropharmacology 2014; 81:95-100. [PMID: 24495399 DOI: 10.1016/j.neuropharm.2014.01.040] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 01/20/2014] [Accepted: 01/24/2014] [Indexed: 01/02/2023]
Abstract
Gabapentin has shown to be effective in animals and humans with acute postoperative and chronic pain. Yet the mechanisms by which gabapentin reduces pain have not been fully addressed. The current study performed in vivo microdialysis in the locus coeruleus (LC) in normal and spinal nerve ligated (SNL) rats to examine the effect of gabapentin on extracellular glutamate concentration and its mechanisms of action with focus on presynaptic GABA-B receptors, astroglial glutamate transporter-1 (GLT-1), and interactions with α2δ subunits of voltage-gated Ca(2+) channels and endogenous noradrenaline. Basal extracellular concentration and tissue content of glutamate in the LC were greater in SNL rats than normal ones. Intravenously administered and LC-perfused gabapentin increased extracellular glutamate concentration in the LC. The net amount of glutamate increased by gabapentin is larger in SNL rats compared with normal ones, although the percentage increases from the baseline did not differ. The gabapentin-related α2δ ligand pregabalin increased extracellular glutamate concentration in the LC, whereas another α2δ ligand, 3-exo-aminobicyclo [2.2.1] heptane-2-exo-carboxylic acid (ABHCA), did not. Selective blockade by the dihydrokainic acid or knock-down of GLT-1 by the small interfering RNA abolished the gabapentin-induced glutamate increase in the LC, whereas blockade of GABA-B receptors by the CGP-35348 and depletion of noradrenalin by the dopamine-β-hydroxylase antibody conjugated to saporin did not. These results suggest that gabapentin induces glutamate release from astrocytes in the LC via GLT-1-dependent mechanisms to stimulate descending inhibition. The present study also demonstrates that this target of gabapentin in astrocytes does not require interaction with α2δ subunits in neurons.
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Affiliation(s)
- Takashi Suto
- Department of Anesthesiology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA
| | - Amie L Severino
- Department of Anesthesiology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA
| | - James C Eisenach
- Department of Anesthesiology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA
| | - Ken-ichiro Hayashida
- Department of Anesthesiology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA.
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39
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Rauck R, Coffey RJ, Schultz DM, Wallace MS, Webster LR, McCarville SE, Grigsby EJ, Page LM. Intrathecal gabapentin to treat chronic intractable noncancer pain. Anesthesiology 2013; 119:675-86. [PMID: 23835590 DOI: 10.1097/aln.0b013e3182a10fbf] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Oral gabapentin is approved as an anticonvulsant medication and to treat postherpetic neuralgia. Its nonopioid properties and presumed spinal site of analgesic action made the study on intrathecal gabapentin attractive to establish the minimum effective dose for a later, pivotal trial. METHODS The authors examined the safety and efficacy of intrathecal gabapentin in a randomized, blinded, placebo-controlled, multicenter trial in a heterogeneous cohort of candidates with chronic pain for intrathecal drug therapy. RESULTS Patients (N = 170) were randomized to receive continuous intrathecal gabapentin (0 [placebo], 1, 6, or 30 mg/day) during 22 days of blinded treatment after implantation of a permanent drug delivery system. The highest dose, 30 mg/day, was selected to maintain a safety margin below the 100-mg/day dose that was explored in a phase 1 study. The authors found no statistically significant difference in the primary outcome measure, which was the numerical pain rating scale and response rate after 3 weeks, for any dose versus placebo. Physical functioning, quality of life, and emotional functioning also revealed no differences. Small, nonsignificant changes occurred in opioid medication use. The most frequent device-related adverse events were transient postimplant (lumbar puncture) headache, pain, and nausea. The most frequent gabapentin-related adverse events were nausea, somnolence, headache, dizziness, fatigue, and peripheral edema. CONCLUSION Twenty-two days of intrathecal gabapentin did not demonstrate statistically significant or clinically meaningful analgesic effects. The study sponsor has no current plans for further studies. Drug-related adverse events were similar to those for oral gabapentin. Most device-related adverse events resulted from the implant surgery or anesthesia.
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Affiliation(s)
- Richard Rauck
- Center for Clinical Research, LLC, Carolinas Pain Institute PA, Winston-Salem, North Carolina, USA
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Yang F, Whang J, Derry WT, Vardeh D, Scholz J. Analgesic treatment with pregabalin does not prevent persistent pain after peripheral nerve injury in the rat. Pain 2013; 155:356-366. [PMID: 24176928 DOI: 10.1016/j.pain.2013.10.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 10/11/2013] [Accepted: 10/21/2013] [Indexed: 12/22/2022]
Abstract
Reducing the risk of chronic postoperative pain through preventive analgesia is an attractive therapeutic concept. Because peripheral nerve lesions are a major cause of chronic pain after surgery, we tested in rats whether analgesic treatment with pregabalin (PGB) has the capacity to mitigate the development of persistent neuropathic pain-like behavior. Starting on the day of spared nerve injury or 1week later, we treated rats with a continuous intrathecal infusion of PGB (300 or 900μg/24hours) or vehicle for up to 28days. Rats receiving early PGB treatment had almost normal withdrawal thresholds for punctate mechanical stimuli and were clearly less sensitive to pinprick or cold stimulation. The responses to punctate mechanical and cold stimulation were still reduced for a brief period after the infusion was terminated, but the difference from vehicle-treated rats was minor. Essentially, the analgesic effect of PGB was limited to the duration of the infusion, whether analgesia started at the time of surgery or with a delay of 1week, independently of the length of the treatment. PGB did not suppress the activation of spinal microglia, indicating that analgesia alone does not eliminate certain pain mechanisms even if they depend, at least partially, on nociceptive input. Unexpectedly, intrathecal infusion of PGB did not inhibit the nerve injury-induced accumulation of its binding target, the voltage-gated calcium channel subunit α2δ1, at primary afferent terminals in the spinal cord. Interference with the synaptic trafficking of α2δ1 is not required to achieve analgesia with PGB.
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Affiliation(s)
- Fang Yang
- Department of Anesthesiology, Columbia University College of Physicians and Surgeons, New York, NY, USA Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA Department of Radiology, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA Department of Neurology, Massachusetts General Hospital, Boston, MA, USA Department of Pharmacology, Columbia University College of Physicians and Surgeons, New York, NY, USA
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Social stress exacerbates the aversion to painful experiences in rats exposed to chronic pain: The role of the locus coeruleus. Pain 2013; 154:2014-2023. [DOI: 10.1016/j.pain.2013.06.021] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 05/28/2013] [Accepted: 06/11/2013] [Indexed: 11/21/2022]
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Stahl SM, Porreca F, Taylor CP, Cheung R, Thorpe AJ, Clair A. The diverse therapeutic actions of pregabalin: is a single mechanism responsible for several pharmacological activities? Trends Pharmacol Sci 2013; 34:332-9. [PMID: 23642658 DOI: 10.1016/j.tips.2013.04.001] [Citation(s) in RCA: 233] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 03/20/2013] [Accepted: 04/03/2013] [Indexed: 12/13/2022]
Abstract
Pregabalin is a specific ligand of the alpha2-delta (α2-δ) auxiliary subunit of voltage-gated calcium channels. A growing body of evidence from studies of anxiety and pain indicate that the observed responses with pregabalin may result from activity at the α2-δ auxiliary protein expressed presynaptically, in several different circuits of the central nervous system (CNS). The disorders that appear to be effectively treated with pregabalin are thematically linked by neuronal dysregulation or hyperexcitation within the CNS. This review proposes how binding to the α2-δ protein target in different regions of the CNS may contribute to the observed clinical activity of pregabalin, as well as to the adverse event profile of the compound. Whether this compound regulates synaptic function via α2-δ in additional conditions is yet to be discovered. The potential of pregabalin to regulate neuronal hyperactivity involving other CNS circuits will require further exploration.
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Affiliation(s)
- Stephen M Stahl
- Department of Psychiatry, University of California, San Diego, CA, USA
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Kukkar A, Bali A, Singh N, Jaggi AS. Implications and mechanism of action of gabapentin in neuropathic pain. Arch Pharm Res 2013; 36:237-51. [PMID: 23435945 DOI: 10.1007/s12272-013-0057-y] [Citation(s) in RCA: 174] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 12/14/2012] [Indexed: 01/25/2023]
Abstract
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.
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Affiliation(s)
- Ankesh Kukkar
- Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala, 147002, Punjab, India
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