1
|
Su Y, Verkhratsky A, Yi C. Targeting connexins: possible game changer in managing neuropathic pain? Trends Mol Med 2024; 30:642-659. [PMID: 38594094 DOI: 10.1016/j.molmed.2024.03.009] [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: 01/23/2024] [Revised: 03/08/2024] [Accepted: 03/18/2024] [Indexed: 04/11/2024]
Abstract
Neuropathic pain is a chronic debilitating condition caused by nerve injury or a variety of diseases. At the core of neuropathic pain lies the aberrant neuronal excitability in the peripheral and/or central nervous system (PNS and CNS). Enhanced connexin expression and abnormal activation of connexin-assembled gap junctional channels are prominent in neuropathic pain along with reactive gliosis, contributing to neuronal hypersensitivity and hyperexcitability. In this review, we delve into the current understanding of how connexin expression and function contribute to the pathogenesis and pathophysiology of neuropathic pain and argue for connexins as potential therapeutic targets for neuropathic pain management.
Collapse
Affiliation(s)
- Yixun Su
- Research Centre, Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, China
| | - Alexei Verkhratsky
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK; Achucarro Center for Neuroscience, IKERBASQUE, Bilbao, Spain; Department of Stem Cell Biology, State Research Institute Centre for Innovative Medicine, Vilnius, Lithuania; Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China.
| | - Chenju Yi
- Research Centre, Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, China; Guangdong Provincial Key Laboratory of Brain Function and Disease, Guangzhou, China; Shenzhen Key Laboratory of Chinese Medicine Active substance screening and Translational Research, Shenzhen, China.
| |
Collapse
|
2
|
Tanei T, Maesawa S, Nishimura Y, Nagashima Y, Ishizaki T, Ando M, Kuwatsuka Y, Hashizume A, Kurasawa S, Saito R. Efficacy of the latest new stimulation patterns of spinal cord stimulation for intractable neuropathic pain compared to conventional stimulation: study protocol for a clinical trial. Trials 2023; 24:604. [PMID: 37742013 PMCID: PMC10517501 DOI: 10.1186/s13063-023-07637-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 09/08/2023] [Indexed: 09/25/2023] Open
Abstract
BACKGROUND Spinal cord stimulation (SCS) is one of the neuromodulation therapies for chronic neuropathic pain. The conventional paresthesia-based SCS involves the application of tonic stimulation that induces a sense of paresthesia. Recently, new SCS stimulation patterns without paresthesia have been developed. Differential target multiplexed (DTM) stimulation and fast-acting subperception therapy (FAST) stimulation are the latest paresthesia-free SCS patterns. METHODS A single-center, open-label, crossover, randomized clinical trial to investigate the superiority of SCS using the latest new stimulation patterns over conventional tonic stimulation for neuropathic pain is planned. This study consists of two steps: SCS trial (first step) and SCS system implantation (second step). In the SCS trial, participants will be randomly assigned to 4 groups receiving stimulation, including tonic, DTM, and FAST. Each stimulation will then be performed for 2 days, and a visual analog scale (VAS) for pain will be evaluated before and after each stimulation pattern. A stimulation-off period for 1 day is set between each stimulation pattern to wash out the residual previous stimulation effects. Pain improvement is defined as more than 33% reduction in the pain VAS. The primary analysis will compare pain improvement between the new stimulation patterns and the conventional tonic stimulation pattern in the SCS trial. The secondary outcomes will be evaluated as follows: (1) the relationships between causative disease and improvement rate by each stimulation pattern; (2) comparison of pain improvement between the DTM and FAST stimulation patterns in all cases and by causative disease; (3) changes in assessment items preoperatively to 24 months after the implantation; (4) preoperative factors associated with long-term effects defined as continuing for more than 12 months; and (5) adverse events related to this study 3 months after the implantation. DISCUSSION This study aims to clarify the effectiveness of the latest new stimulation patterns compared to the conventional tonic stimulation. In addition, which stimulation pattern is most effective for which kind of causative disease will be clarified. TRIAL REGISTRATION Japan Registry of Clinical Trials (jRCT) 1,042,220,094. Registered on 21 November 2022, and last modified on 6 January 2023. jRCT is an approved member of the Primary Registry Network of WHO ICTRP.
Collapse
Affiliation(s)
- Takafumi Tanei
- Department of Neurosurgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-Cho, Showa-Ku, Nagoya, Aichi, 466-8550, Japan.
| | - Satoshi Maesawa
- Department of Neurosurgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-Cho, Showa-Ku, Nagoya, Aichi, 466-8550, Japan
| | - Yusuke Nishimura
- Department of Neurosurgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-Cho, Showa-Ku, Nagoya, Aichi, 466-8550, Japan
| | - Yoshitaka Nagashima
- Department of Neurosurgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-Cho, Showa-Ku, Nagoya, Aichi, 466-8550, Japan
| | - Tomotaka Ishizaki
- Department of Neurosurgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-Cho, Showa-Ku, Nagoya, Aichi, 466-8550, Japan
| | - Masahiko Ando
- Department of Advanced Medicine, Nagoya University Graduate School of Medicine, 65 Tsurumai-Cho, Showa-Ku, Nagoya, Aichi, 466-8550, Japan
| | - Yachiyo Kuwatsuka
- Department of Advanced Medicine, Nagoya University Graduate School of Medicine, 65 Tsurumai-Cho, Showa-Ku, Nagoya, Aichi, 466-8550, Japan
| | - Atsushi Hashizume
- Department of Clinical Research Education, Nagoya University Graduate School of Medicine, 65 Tsurumai-Cho, Showa-Ku, Nagoya, Aichi, 466-8550, Japan
| | - Shimon Kurasawa
- Department of Clinical Research Education, Nagoya University Graduate School of Medicine, 65 Tsurumai-Cho, Showa-Ku, Nagoya, Aichi, 466-8550, Japan
| | - Ryuta Saito
- Department of Neurosurgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-Cho, Showa-Ku, Nagoya, Aichi, 466-8550, Japan
| |
Collapse
|
3
|
Varrassi G, Tamburin S, Zis P, Guardamagna VA, Paladini A, Rekatsina M. What's New in Neuropathy? Cureus 2023; 15:e44952. [PMID: 37818524 PMCID: PMC10561699 DOI: 10.7759/cureus.44952] [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: 08/17/2023] [Accepted: 09/06/2023] [Indexed: 10/12/2023] Open
Abstract
Neuropathic pain presents diagnostic and treatment challenges. Despite recent advances in our understanding of the diagnosis and treatment of neuropathy, much remains to be elucidated. Familiar with neuropathy is the paradox that aberrant nerve signaling causes both sensory loss and pain. Voltage-gated sodium channels play an important role in neuronal electrogenesis and communication among neurons, and their dysregulation leads to hyperexcitability and pain. While numerous validated diagnostic assessment tools are available for neuropathy, patients often experience a diagnostic delay about the cause of their neuropathy. New research is defining more specific types of neuropathy beyond peripheral and central forms. The prevalence of pain varies by type of neuropathy, with chronic idiopathic axonal polyneuropathy associated with the highest proportion of patients experiencing pain. In the majority of types, it exceeds 50%. Gluten neuropathy, a form of peripheral neuropathy, is a new diagnostic consideration. It may require electrochemical conductance testing of hands and feet to test for sudomotor dysfunction. Among those with serologically confirmed gluten sensitivity or celiac disease, gluten neuropathy is a common neurological manifestation and may be addressed at least partially by a gluten-free diet. In Greece, a new neuropathic pain registry was created in 2014 in order to help gather data from real-world neuropathic pain patients. While still in its earliest phase, this registry has already produced demographic and treatment data that suggest suboptimal prescribing and less than recommended use of interventional procedures. Awareness campaigns are underway to encourage more Greek pain clinics to participate in this important registry.
Collapse
Affiliation(s)
| | | | - Panagiotis Zis
- Department of Neurology, University of Cyprus, Nicosia, CYP
| | | | - Antonella Paladini
- Department of Life, Health and Environmental Sciences (MESVA), University of L'Aquila, L'Aquila, ITA
| | - Martina Rekatsina
- Department of Anesthesiology and Pain Management, University of Athens, Athens, GRC
| |
Collapse
|
4
|
Kaur M, Misra S, Swarnkar P, Patel P, Das Kurmi B, Das Gupta G, Singh A. Understanding the role of hyperglycemia and the molecular mechanism associated with diabetic neuropathy and possible therapeutic strategies. Biochem Pharmacol 2023; 215:115723. [PMID: 37536473 DOI: 10.1016/j.bcp.2023.115723] [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: 04/24/2023] [Revised: 07/26/2023] [Accepted: 07/27/2023] [Indexed: 08/05/2023]
Abstract
Diabetic neuropathy is a neuro-degenerative disorder that encompasses numerous factors that impact peripheral nerves in the context of diabetes mellitus (DM). Diabetic peripheral neuropathy (DPN) is very prevalent and impacts 50% of diabetic patients. DPN is a length-dependent peripheral nerve lesion that primarily causes distal sensory loss, discomfort, and foot ulceration that may lead to amputation. The pathophysiology is yet to be fully understood, but current literature on the pathophysiology of DPN revolves around understanding various signaling cascades involving the polyol, hexosamine, protein-kinase C, AGE, oxidative stress, and poly (ADP ribose) polymerase pathways. The results of research have suggested that hyperglycemia target Schwann cells and in severe cases, demyelination resulting in central and peripheral sensitization is evident in diabetic patients. Various diagnostic approaches are available, but detection at an early stage remains a challenge. Traditional analgesics and opioids that can be used "as required" have not been the mainstay of treatment thus far. Instead, anticonvulsants and antidepressants that must be taken routinely over time have been the most common treatments. For now, prolonging life and preserving the quality of life are the ultimate goals of diabetes treatment. Furthermore, the rising prevalence of DPN has substantial consequences for occupational therapy because such therapy is necessary for supporting wellness, warding off other chronic-diseases, and avoiding the development of a disability; this is accomplished by engaging in fulfilling activities like yoga, meditation, and physical exercise. Therefore, occupational therapy, along with palliative therapy, may prove to be crucial in halting the onset of neuropathic-symptoms and in lessening those symptoms once they have occurred.
Collapse
Affiliation(s)
- Mandeep Kaur
- Department of Pharmacology, ISF College of Pharmacy, GT Road, Ghal Kalan, Moga142001, Punjab, India
| | - Sakshi Misra
- Department of Pharmacology, ISF College of Pharmacy, GT Road, Ghal Kalan, Moga142001, Punjab, India
| | - Priyanka Swarnkar
- Department of Pharmacology, ISF College of Pharmacy, GT Road, Ghal Kalan, Moga142001, Punjab, India
| | - Preeti Patel
- Department of Pharmaceutical Chemistry, ISF College of Pharmacy, GT Road, Ghal Kalan, Moga 142001, Punjab, India
| | - Balak Das Kurmi
- Department of Pharmaceutics, ISF College of Pharmacy, GT Road, Ghal Kalan, Moga 142001, Punjab, India
| | - Ghanshyam Das Gupta
- Department of Pharmaceutics, ISF College of Pharmacy, GT Road, Ghal Kalan, Moga 142001, Punjab, India
| | - Amrita Singh
- Department of Pharmacology, ISF College of Pharmacy, GT Road, Ghal Kalan, Moga142001, Punjab, India.
| |
Collapse
|
5
|
Ferraro MC, Cashin AG, Wand BM, Smart KM, Berryman C, Marston L, Moseley GL, McAuley JH, O'Connell NE. Interventions for treating pain and disability in adults with complex regional pain syndrome- an overview of systematic reviews. Cochrane Database Syst Rev 2023; 6:CD009416. [PMID: 37306570 PMCID: PMC10259367 DOI: 10.1002/14651858.cd009416.pub3] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
BACKGROUND Complex regional pain syndrome (CRPS) is a chronic pain condition that usually occurs in a limb following trauma or surgery. It is characterised by persisting pain that is disproportionate in magnitude or duration to the typical course of pain after similar injury. There is currently no consensus regarding the optimal management of CRPS, although a broad range of interventions have been described and are commonly used. This is the first update of the original Cochrane review published in Issue 4, 2013. OBJECTIVES To summarise the evidence from Cochrane and non-Cochrane systematic reviews of the efficacy, effectiveness, and safety of any intervention used to reduce pain, disability, or both, in adults with CRPS. METHODS We identified Cochrane reviews and non-Cochrane reviews through a systematic search of Ovid MEDLINE, Ovid Embase, Cochrane Database of Systematic Reviews, CINAHL, PEDro, LILACS and Epistemonikos from inception to October 2022, with no language restrictions. We included systematic reviews of randomised controlled trials that included adults (≥18 years) diagnosed with CRPS, using any diagnostic criteria. Two overview authors independently assessed eligibility, extracted data, and assessed the quality of the reviews and certainty of the evidence using the AMSTAR 2 and GRADE tools respectively. We extracted data for the primary outcomes pain, disability and adverse events, and the secondary outcomes quality of life, emotional well-being, and participants' ratings of satisfaction or improvement with treatment. MAIN RESULTS: We included six Cochrane and 13 non-Cochrane systematic reviews in the previous version of this overview and five Cochrane and 12 non-Cochrane reviews in the current version. Using the AMSTAR 2 tool, we judged Cochrane reviews to have higher methodological quality than non-Cochrane reviews. The studies in the included reviews were typically small and mostly at high risk of bias or of low methodological quality. We found no high-certainty evidence for any comparison. There was low-certainty evidence that bisphosphonates may reduce pain intensity post-intervention (standardised mean difference (SMD) -2.6, 95% confidence interval (CI) -1.8 to -3.4, P = 0.001; I2 = 81%; 4 trials, n = 181) and moderate-certainty evidence that they are probably associated with increased adverse events of any nature (risk ratio (RR) 2.10, 95% CI 1.27 to 3.47; number needed to treat for an additional harmful outcome (NNTH) 4.6, 95% CI 2.4 to 168.0; 4 trials, n = 181). There was moderate-certainty evidence that lidocaine local anaesthetic sympathetic blockade probably does not reduce pain intensity compared with placebo, and low-certainty evidence that it may not reduce pain intensity compared with ultrasound of the stellate ganglion. No effect size was reported for either comparison. There was low-certainty evidence that topical dimethyl sulfoxide may not reduce pain intensity compared with oral N-acetylcysteine, but no effect size was reported. There was low-certainty evidence that continuous bupivacaine brachial plexus block may reduce pain intensity compared with continuous bupivacaine stellate ganglion block, but no effect size was reported. For a wide range of other commonly used interventions, the certainty in the evidence was very low and provides insufficient evidence to either support or refute their use. Comparisons with low- and very low-certainty evidence should be treated with substantial caution. We did not identify any RCT evidence for routinely used pharmacological interventions for CRPS such as tricyclic antidepressants or opioids. AUTHORS' CONCLUSIONS Despite a considerable increase in included evidence compared with the previous version of this overview, we identified no high-certainty evidence for the effectiveness of any therapy for CRPS. Until larger, high-quality trials are undertaken, formulating an evidence-based approach to managing CRPS will remain difficult. Current non-Cochrane systematic reviews of interventions for CRPS are of low methodological quality and should not be relied upon to provide an accurate and comprehensive summary of the evidence.
Collapse
Affiliation(s)
- Michael C Ferraro
- Centre for Pain IMPACT, Neuroscience Research Australia, Sydney, Australia
- School of Health Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Aidan G Cashin
- Centre for Pain IMPACT, Neuroscience Research Australia, Sydney, Australia
- School of Health Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Benedict M Wand
- The School of Health Sciences and Physiotherapy, The University of Notre Dame Australia, Fremantle, Australia
| | - Keith M Smart
- UCD School of Public Health, Physiotherapy and Sports Science, University College Dublin, Dublin, Ireland
- Physiotherapy Department, St Vincent's University Hospital, Dublin, Ireland
| | - Carolyn Berryman
- IIMPACT in Health, University of South Australia, Kaurna Country, Adelaide, South Australia, Australia
- School of Biomedicine, The University of Adelaide, Kaurna Country, Adelaide, Australia
| | - Louise Marston
- Department of Primary Care and Population Health, University College London, London, UK
| | - G Lorimer Moseley
- IIMPACT in Health, University of South Australia, Kaurna Country, Adelaide, South Australia, Australia
| | - James H McAuley
- Centre for Pain IMPACT, Neuroscience Research Australia, Sydney, Australia
- School of Health Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Neil E O'Connell
- Department of Health Sciences, Centre for Health and Wellbeing Across the Lifecourse, Brunel University London, Uxbridge, UK
| |
Collapse
|
6
|
Amorizzo E, De Sanctis F, Colini Baldeschi G. Fast-Acting Sub-perception Spinal Cord Stimulation for a Case of Painful Diabetic Polyneuropathy. Just an Antalgic Treatment or Even a Therapy? Anesth Pain Med 2023; 13:e134901. [PMID: 37529140 PMCID: PMC10389032 DOI: 10.5812/aapm-134901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 02/15/2023] [Accepted: 02/28/2023] [Indexed: 08/03/2023] Open
Abstract
Introduction Painful diabetic polyneuropathy (P-DPN) occurs in 20% - 30% of diabetic patients. Currently, therapeutic strategies include lifestyle modifications, good glycemic control, and neuropathic pain drugs. Spinal cord stimulation (SCS) has been shown to be successful in patients who have not responded to other treatments. The American Diabetes Association strongly recommends early screening and diagnosis for this condition through clinical tests and nerve conduction study (NCS). In recent years, high-resolution ultrasonography (HRUS) with the analysis of cross-sectional area (CSA) has shown an increasingly important role in detecting changes in the nervous structures, blood vessels, echo, and mobility of the nerve. Cross-sectional area is frequently enlarged in these patients, even those with normal NCS. We aimed to use SCS with fast-acting sub-perception therapy (FAST) modality to treat P-DPN. We also evaluated the CSA of the involved nerves before and after treatment. Case Presentation A 58-year-old female patient was referred to our hospital in 2020 (Civitavecchia, Italy). She suffered from P-DPN for 3 years and did not respond to conventional medical treatments. Preoperative electromyography (EMG) was negative for radiculopathy, while electroneurography (ENG) showed a reduction in sensory conduction velocity (SCV) in the sural nerve (SN) bilaterally. Clinical tests on perceived pain and quality of life showed high severity. The report was confirmed by HRUS with enlargement of the CSA of the posterior tibial nerve (PTN), external popliteal nerve (EPN), and SN. The patient was successfully subjected to all-in-one SCS implantation in the FAST modality. She obtained immediate pain relief that remained unaltered at the 3-month follow-up. The patient completely discontinued drug therapy. One month after implantation, ENG highlighted an increased SN SCV, and the HRUS of PTN EPN and SN showed a significant reduction in CSA in all 3 nerves involved. Conclusions Early diagnosis and treatment are crucial in improving the clinical outcome of P-DPN, but there is still no gold standard therapy. Spinal cord stimulation in the new FAST modality was effective in this clinical case. The pain relief was supported by a significant reduction in the CSA of the studied nerves observed on HRUS 1 month after SCS implantation. The results and the improvement of a pathological nervous pattern, albeit with a short follow-up of only 3 months, could suggest not only a symptomatic but perhaps also a therapeutic role of SCS in P-DPN.
Collapse
Affiliation(s)
- Ezio Amorizzo
- Pain Unit, San Paolo Hospital Civitavecchia, Italy
- Pain Clinic Roma, Rome, Italy
| | - Francesca De Sanctis
- Department of Anesthesia, Critical Care and Pain Medicine, Az. Osp S. Maria Terni, Terni, Italy
| | | |
Collapse
|
7
|
Study on structure-activity relationship (SAR) of simplified mirogabalin derivatives as voltage-gated calcium channel α2δ ligands for the treatment of chronic neuropathic pain. Med Chem Res 2022. [DOI: 10.1007/s00044-022-03006-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
8
|
Pharmacologic therapies of pain in patients with spinal cord injury: a systematic review. Spinal Cord Ser Cases 2022; 8:65. [DOI: 10.1038/s41394-022-00529-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Revised: 06/07/2022] [Accepted: 06/09/2022] [Indexed: 11/08/2022] Open
|
9
|
Kopsky DJ, van Eijk RPA, Warendorf JK, Keppel Hesselink JM, Notermans NC, Vrancken AFJE. Enriched enrollment randomized double-blind placebo-controlled cross-over trial with phenytoin cream in painful chronic idiopathic axonal polyneuropathy (EPHENE): a study protocol. Trials 2022; 23:888. [PMID: 36273216 PMCID: PMC9587538 DOI: 10.1186/s13063-022-06806-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 09/30/2022] [Indexed: 11/10/2022] Open
Abstract
Background Patients with chronic idiopathic axonal polyneuropathy (CIAP) can have neuropathic pain that significantly impacts quality of life. Oral neuropathic pain medication often has insufficient pain relief and side effects. Topical phenytoin cream could circumvent these limitations. The primary objectives of this trial are to evaluate (1) efficacy in pain reduction and (2) safety of phenytoin cream in patients with painful CIAP. The main secondary objective is to explore the usefulness of a double-blind placebo-controlled response test (DOBRET) to identify responders to sustained pain relief with phenytoin cream. Methods This 6-week, enriched enrollment randomized double-blind, placebo-controlled triple cross-over trial compares phenytoin 20%, 10% and placebo cream in 48 participants with painful CIAP. Enriched enrollment is based on a positive DOBRET in 48 participants who experience within 30 minutes ≥2 points pain reduction on the 11-point numerical rating scale (NRS) in the phenytoin 10% cream applied area and ≥1 point difference in pain reduction on the NRS between phenytoin 10% and placebo cream applied area, in favour of the former. To explore whether DOBRET has predictive value for sustained pain relief, 24 DOBRET-negative participants will be included. An open-label extension phase is offered with phenytoin 20% cream for up to one year, to study long-term safety. The main inclusion criteria are a diagnosis of CIAP and symmetrical neuropathic pain with a mean weekly pain score of ≥4 and <10 on the NRS. The primary outcome is the mean difference between phenytoin 20% versus placebo cream in 7-day average pain intensity, as measured by the NRS, over week 2 in DOBRET positive participants. Key secondary outcomes include the mean difference in pain intensity between phenytoin 10% and phenytoin 20% cream, and between phenytoin 10% and placebo cream. Furthermore, differences between the 3 interventions will be evaluated on the Neuropathic Pain Symptom Inventory, EuroQol EQ5-5D-5L, and evaluation of adverse events. Discussion This study will provide evidence on the efficacy and safety of phenytoin cream in patients with painful CIAP and will give insight into the usefulness of DOBRET as a way of personalized medicine to identify responders to sustained pain relief with phenytoin cream. Trial registration ClinicalTrials.gov NCT04647877. Registered on 1 December 2020.
Collapse
Affiliation(s)
- David J Kopsky
- Institute for Neuropathic Pain, Amsterdam / Soest / Bosch en Duin, The Netherlands. .,Department of Neurology, Brain Centre University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.
| | - Ruben P A van Eijk
- Department of Neurology, Brain Centre University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.,Biostatistics & Research Support, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Janna K Warendorf
- Department of Neurology, Brain Centre University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | | | - Nicolette C Notermans
- Department of Neurology, Brain Centre University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Alexander F J E Vrancken
- Department of Neurology, Brain Centre University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| |
Collapse
|
10
|
De Stefano G, Leone C, Di Pietro G, Esposito N, Falco P, Galosi E, Litewczuk D, Mollica C, Truini A, Di Stefano G. Unravelling the role of unmyelinated nerve fibres in trigeminal neuralgia with concomitant continuous pain. Clin Neurophysiol 2022; 142:52-58. [DOI: 10.1016/j.clinph.2022.07.502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/13/2022] [Accepted: 07/22/2022] [Indexed: 11/03/2022]
|
11
|
Lischka A, Lassuthova P, Çakar A, Record CJ, Van Lent J, Baets J, Dohrn MF, Senderek J, Lampert A, Bennett DL, Wood JN, Timmerman V, Hornemann T, Auer-Grumbach M, Parman Y, Hübner CA, Elbracht M, Eggermann K, Geoffrey Woods C, Cox JJ, Reilly MM, Kurth I. Genetic pain loss disorders. Nat Rev Dis Primers 2022; 8:41. [PMID: 35710757 DOI: 10.1038/s41572-022-00365-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/10/2022] [Indexed: 01/05/2023]
Abstract
Genetic pain loss includes congenital insensitivity to pain (CIP), hereditary sensory neuropathies and, if autonomic nerves are involved, hereditary sensory and autonomic neuropathy (HSAN). This heterogeneous group of disorders highlights the essential role of nociception in protecting against tissue damage. Patients with genetic pain loss have recurrent injuries, burns and poorly healing wounds as disease hallmarks. CIP and HSAN are caused by pathogenic genetic variants in >20 genes that lead to developmental defects, neurodegeneration or altered neuronal excitability of peripheral damage-sensing neurons. These genetic variants lead to hyperactivity of sodium channels, disturbed haem metabolism, altered clathrin-mediated transport and impaired gene regulatory mechanisms affecting epigenetic marks, long non-coding RNAs and repetitive elements. Therapies for pain loss disorders are mainly symptomatic but the first targeted therapies are being tested. Conversely, chronic pain remains one of the greatest unresolved medical challenges, and the genes and mechanisms associated with pain loss offer new targets for analgesics. Given the progress that has been made, the coming years are promising both in terms of targeted treatments for pain loss disorders and the development of innovative pain medicines based on knowledge of these genetic diseases.
Collapse
Affiliation(s)
- Annette Lischka
- Institute of Human Genetics, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Petra Lassuthova
- Department of Paediatric Neurology, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, Prague, Czech Republic
| | - Arman Çakar
- Neuromuscular Unit, Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Christopher J Record
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
| | - Jonas Van Lent
- Peripheral Neuropathy Research Group, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium.,Laboratory of Neuromuscular Pathology, Institute Born Bunge, Antwerp, Belgium
| | - Jonathan Baets
- Laboratory of Neuromuscular Pathology, Institute Born Bunge, Antwerp, Belgium.,Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.,Neuromuscular Reference Centre, Department of Neurology, Antwerp University Hospital, Antwerp, Belgium
| | - Maike F Dohrn
- Department of Neurology, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany.,Dr. John T. Macdonald Foundation, Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Jan Senderek
- Friedrich-Baur-Institute, Department of Neurology, Ludwig-Maximilians-University, Munich, Germany
| | - Angelika Lampert
- Institute of Physiology, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany
| | - David L Bennett
- Nuffield Department of Clinical Neuroscience, Oxford University, Oxford, UK
| | - John N Wood
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Vincent Timmerman
- Peripheral Neuropathy Research Group, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium.,Laboratory of Neuromuscular Pathology, Institute Born Bunge, Antwerp, Belgium
| | - Thorsten Hornemann
- Department of Clinical Chemistry, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Michaela Auer-Grumbach
- Department of Orthopedics and Trauma Surgery, Medical University of Vienna, Vienna, Austria
| | - Yesim Parman
- Neuromuscular Unit, Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | | | - Miriam Elbracht
- Institute of Human Genetics, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Katja Eggermann
- Institute of Human Genetics, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany
| | - C Geoffrey Woods
- Cambridge Institute for Medical Research, Keith Peters Building, Cambridge Biomedical Campus, Cambridge, UK
| | - James J Cox
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Mary M Reilly
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
| | - Ingo Kurth
- Institute of Human Genetics, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany.
| |
Collapse
|
12
|
Hewitt D, Newton-Fenner A, Henderson J, Fallon NB, Brown C, Stancak A. Intensity-dependent modulation of cortical somatosensory processing during external, low-frequency peripheral nerve stimulation in humans. J Neurophysiol 2022; 127:1629-1641. [PMID: 35611988 PMCID: PMC9190739 DOI: 10.1152/jn.00511.2021] [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] [Indexed: 01/20/2023] Open
Abstract
External low-frequency peripheral nerve stimulation (LFS) has been proposed as a novel method for neuropathic pain relief. Previous studies have reported that LFS elicits long-term depression-like effects on human pain perception when delivered at noxious intensities, whereas lower intensities are ineffective. To shed light on cortical regions mediating the effects of LFS, we investigated changes in somatosensory-evoked potentials (SEPs) during four LFS intensities. LFS was applied to the radial nerve (600 pulses, 1 Hz) of 24 healthy participants at perception (1 times), low (5 times), medium (10 times), and high intensities (15 times detection threshold). SEPs were recorded during LFS, and averaged SEPs in 10 consecutive 1-min epochs of LFS were analyzed using source dipole modeling. Changes in resting electroencephalography (EEG) were investigated after each LFS block. Source activity in the midcingulate cortex (MCC) decreased linearly during LFS, with greater attenuation at stronger LFS intensities, and in the ipsilateral operculo-insular cortex during the two lowest LFS stimulus intensities. Increased LFS intensities resulted in greater augmentation of contralateral primary sensorimotor cortex (SI/MI) activity. Stronger LFS intensities were followed by increased α (alpha, 9-11 Hz) band power in SI/MI and decreased θ (theta, 3-5 Hz) band power in MCC. Intensity-dependent attenuation of MCC activity with LFS is consistent with a state of long-term depression. Sustained increases in contralateral SI/MI activity suggests that effects of LFS on somatosensory processing may also be dependent on satiation of SI/MI. Further research could clarify if the activation of SI/MI during LFS competes with nociceptive processing in neuropathic pain.NEW & NOTEWORTHY Somatosensory-evoked potentials during low-frequency stimulation of peripheral nerves were examined at graded stimulus intensities. Low-frequency stimulation was associated with decreased responsiveness in the midcingulate cortex and increased responsiveness in primary sensorimotor cortex. Greater intensities were associated with increased midcingulate cortex θ band power and decreased sensorimotor cortex α band power. Results further previous evidence of an inhibition of somatosensory processing during and after low-frequency stimulation and point toward a potential augmentation of activity in somatosensory processing regions.
Collapse
Affiliation(s)
- Danielle Hewitt
- 1Department of Psychological Sciences, grid.10025.36University of Liverpool, Liverpool, United Kingdom
| | - Alice Newton-Fenner
- 1Department of Psychological Sciences, grid.10025.36University of Liverpool, Liverpool, United Kingdom,2Institute for Risk and Uncertainty, University of Liverpool, Liverpool, United Kingdom
| | - Jessica Henderson
- 1Department of Psychological Sciences, grid.10025.36University of Liverpool, Liverpool, United Kingdom
| | - Nicholas B. Fallon
- 1Department of Psychological Sciences, grid.10025.36University of Liverpool, Liverpool, United Kingdom
| | - Christopher Brown
- 1Department of Psychological Sciences, grid.10025.36University of Liverpool, Liverpool, United Kingdom
| | - Andrej Stancak
- 1Department of Psychological Sciences, grid.10025.36University of Liverpool, Liverpool, United Kingdom,2Institute for Risk and Uncertainty, University of Liverpool, Liverpool, United Kingdom
| |
Collapse
|
13
|
Furka A, Simkó C, Kostyál L, Szabó I, Valikovics A, Fekete G, Tornyi I, Oross E, Révész J. Treatment Algorithm for Cancerous Wounds: A Systematic Review. Cancers (Basel) 2022; 14:cancers14051203. [PMID: 35267512 PMCID: PMC8909326 DOI: 10.3390/cancers14051203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/14/2022] [Accepted: 02/24/2022] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND In advanced cancer stage the incidence of cancerous wounds is about 5%, and the estimated life expectancy is not more than 6 to 12 months. Without interdisciplinary and individualized treatment strategy, symptoms progress, and adversely influence quality of life. METHODS Authors collected different treatment algorithms for cancerous wound published by wide scale of medical expertise, and summarized surgical, oncological, radiation oncological, nursing and palliative care aspects based on radiological information. RESULTS Interdisciplinary approach with continuous consultation between various specialists can solve or ease the hopeless cases. CONCLUSIONS This distressing condition needs a comprehensive treatment solution to alleviate severe symptoms. Non-healing fungating wounds without effective therapy are severe socio-economic burden for all participants, including patients, caregivers, and health services. In this paper authors collected recommendations for further guideline that is essential in the near future.
Collapse
Affiliation(s)
- Andrea Furka
- Centre of Clinical Oncology and Radiotherapy, Borsod-Abaúj-Zemplén County Hospital and University Teaching Hospital, 3526 Miskolc, Hungary; (I.S.); (A.V.); (G.F.); (E.O.); (J.R.)
- Department of Clinical Radiology, Faculty of Health Care, Institute of Practical Methodology and Diagnostics, University of Miskolc, 3526 Miskolc, Hungary;
- Correspondence: ; Tel.: +36-309988499
| | - Csaba Simkó
- Erzsébet Hospice, Borsod-Abaúj-Zemplén County Hospital and University Teaching Hospital Miskolc, 3526 Miskolc, Hungary;
| | - László Kostyál
- Department of Clinical Radiology, Faculty of Health Care, Institute of Practical Methodology and Diagnostics, University of Miskolc, 3526 Miskolc, Hungary;
- Department of Diagnostic Imaging, Borsod-Abaúj-Zemplén County Hospital and University Teaching Hospital Miskolc, 3526 Miskolc, Hungary
| | - Imre Szabó
- Centre of Clinical Oncology and Radiotherapy, Borsod-Abaúj-Zemplén County Hospital and University Teaching Hospital, 3526 Miskolc, Hungary; (I.S.); (A.V.); (G.F.); (E.O.); (J.R.)
| | - Anikó Valikovics
- Centre of Clinical Oncology and Radiotherapy, Borsod-Abaúj-Zemplén County Hospital and University Teaching Hospital, 3526 Miskolc, Hungary; (I.S.); (A.V.); (G.F.); (E.O.); (J.R.)
| | - Gábor Fekete
- Centre of Clinical Oncology and Radiotherapy, Borsod-Abaúj-Zemplén County Hospital and University Teaching Hospital, 3526 Miskolc, Hungary; (I.S.); (A.V.); (G.F.); (E.O.); (J.R.)
| | - Ilona Tornyi
- Department of Human Genetics, University of Debrecen, 4032 Debrecen, Hungary;
- Biosystems Immunolab Zrt., 4032 Debrecen, Hungary
| | - Endre Oross
- Centre of Clinical Oncology and Radiotherapy, Borsod-Abaúj-Zemplén County Hospital and University Teaching Hospital, 3526 Miskolc, Hungary; (I.S.); (A.V.); (G.F.); (E.O.); (J.R.)
| | - János Révész
- Centre of Clinical Oncology and Radiotherapy, Borsod-Abaúj-Zemplén County Hospital and University Teaching Hospital, 3526 Miskolc, Hungary; (I.S.); (A.V.); (G.F.); (E.O.); (J.R.)
- Department of Clinical Radiology, Faculty of Health Care, Institute of Practical Methodology and Diagnostics, University of Miskolc, 3526 Miskolc, Hungary;
| |
Collapse
|
14
|
IQM-PC332, a Novel DREAM Ligand with Antinociceptive Effect on Peripheral Nerve Injury-Induced Pain. Int J Mol Sci 2022; 23:ijms23042142. [PMID: 35216258 PMCID: PMC8876042 DOI: 10.3390/ijms23042142] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 02/07/2022] [Accepted: 02/12/2022] [Indexed: 02/04/2023] Open
Abstract
Neuropathic pain is a form of chronic pain arising from damage of the neural cells that sense, transmit or process sensory information. Given its growing prevalence and common refractoriness to conventional analgesics, the development of new drugs with pain relief effects constitutes a prominent clinical need. In this respect, drugs that reduce activity of sensory neurons by modulating ion channels hold the promise to become effective analgesics. Here, we evaluated the mechanical antinociceptive effect of IQM-PC332, a novel ligand of the multifunctional protein downstream regulatory element antagonist modulator (DREAM) in rats subjected to chronic constriction injury of the sciatic nerve as a model of neuropathic pain. IQM-PC332 administered by intraplantar (0.01–10 µg) or intraperitoneal (0.02–1 µg/kg) injection reduced mechanical sensitivity by ≈100% of the maximum possible effect, with ED50 of 0.27 ± 0.05 µg and 0.09 ± 0.01 µg/kg, respectively. Perforated-patch whole-cell recordings in isolated dorsal root ganglion (DRG) neurons showed that IQM-PC332 (1 and 10 µM) reduced ionic currents through voltage-gated K+ channels responsible for A-type potassium currents, low, T-type, and high voltage-activated Ca2+ channels, and transient receptor potential vanilloid-1 (TRPV1) channels. Furthermore, IQM-PC332 (1 µM) reduced electrically evoked action potentials in DRG neurons from neuropathic animals. It is suggested that by modulating multiple DREAM–ion channel signaling complexes, IQM-PC332 may serve a lead compound of novel multimodal analgesics.
Collapse
|