Review
Clinical Neurology
Daniel Fernando Arias Betancur, Maria da Graca Lopes Tarrago, Iraci Lucena da Silva Torres, Felipe Fregni, Wolnei Caumo
Summary: The review of cortical neurophysiological changes in CPSP patients revealed limitations such as heterogeneity in parameter measurements, lack of a control group without pain, and absence of consistent and validated diagnosis criteria. Despite these limitations, the dataset provides evidence for improving understanding of CPSP physiopathology and supports the development of a diagnostic framework to enhance future research on somatosensory sequelae following stroke.
FRONTIERS IN NEUROLOGY
(2021)
Article
Anesthesiology
Bao-Chun Jiang, Jing Zhang, Bin Wu, Ming Jiang, Hanzhong Cao, Hao Wu, Yong-Jing Gao
Summary: This study identified the involvement of Gpr151 in trigeminal neuropathic pain, showing its role in activating ERK-dependent neuroinflammation through G alpha i protein. Mutation of Gpr151 reduced the expression of neuroinflammation-related genes and alleviated mechanical allodynia.
Article
Clinical Neurology
Anna K. Becker, Alexandru Babes, Miriam M. Duell, Mohammad Khalil, Zoltan Kender, Jan Groener, Barbara Namer, Peter W. Reeh, Susanne K. Sauer
Summary: This study investigates the contribution of MGO to the development of pain and hyperalgesia in diabetic neuropathy. It found that TRPA1-expressing C-nociceptors play a crucial role in the development of spontaneous activity and sensitization in response to MGO.
JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM
(2023)
Article
Anesthesiology
Miriam M. Duell, Martina Stengel, Vivien Ries, Marion Strupf, Peter W. Reeh, Andreas E. Kremer, Barbara Namer
Summary: LPA can cause pain and itch in humans depending on the mode of application and activates afferent human C fibers.
Article
Clinical Neurology
Calogero Malfitano, Angela Rossetti, Stefano Scarano, Chiara Malloggi, Luigi Tesio
Summary: In this study, a patient with thalamic stroke and pain symptoms showed improvement in pain and paresthesia after receiving rTMS treatment. The recovery in motor cortex excitability of the affected hemisphere was associated with the clinical improvement in this central post-stroke pain case.
FRONTIERS IN NEUROLOGY
(2021)
Review
Neurosciences
Rabia Bouali-Benazzouz, Marc Landry, Abdelhamid Benazzouz, Pascal Fossat
Summary: Animal models play a crucial role in studying neuropathic pain, but objective assessment of pain and validating pain phenotypes present challenges. Utilizing various behavioral approaches to investigate and validate pain phenotypes can help uncover novel pain mechanisms.
PROGRESS IN NEUROBIOLOGY
(2021)
Article
Immunology
Kazue Hisaoka-Nakashima, Kodai Moriwaki, Natsuki Yoshimoto, Toshiki Yoshii, Yoki Nakamura, Yukio Ago, Norimitsu Morioka
Summary: Neuropathic pain causes severe pain and comorbidities such as cognitive impairment, which are not effectively treated with current analgesics. This study demonstrates the role of interleukin-6 (IL-6) in neuropathic pain and cognitive impairment. Blocking the IL-6 receptor improves cognitive impairment, while inhibiting IL-6 activity reduces allodynia.
INTERNATIONAL IMMUNOPHARMACOLOGY
(2022)
Article
Clinical Neurology
Georgina Palomes-Borrajo, Jordi Badia, Xavier Navarro, Clara Penas
Summary: Neuropathic pain is a common disability caused by enhanced neuronal excitability after nervous system injury, requiring modifications of transcriptional programs. Inhibition of BET proteins may be a promising therapy for reducing neuropathic pain after neural injury.
Article
Behavioral Sciences
Marta Falkowska, Niels R. Ntamati, Natalie E. Nevian, Thomas Nevian, Mario A. Acuna
Summary: Depression is often seen in patients with chronic pain, but there is a lack of effective pharmacological treatments. Environmental enrichment has been suggested as an alternative approach to alleviate pain-induced depression, but its underlying mechanisms are still unclear. The anterior cingulate cortex (ACC) plays a crucial role in processing pain-related negative emotions and plasticity in this region is associated with depressive symptoms. This study investigated the effects of different durations of environmental enrichment on pain sensitivity and depression-like behaviors in a mouse model of neuropathic pain. We also examined the electrophysiological properties of pyramidal neurons in the ACC and correlated them with behavioral outcomes. The findings showed that early exposure to an enriched environment alone did not prevent the development of pain-induced depression-like symptoms. However, extending the enrichment after injury prevented depression and reduced mechanical hypersensitivity. Increased neuronal excitability in the ACC was associated with the depressive phenotype, which was reversed by the environmental enrichment. These results suggest that improving environmental factors can enhance resilience to chronic pain-related depression and support the use of non-pharmacological interventions as potential treatment strategies.
FRONTIERS IN BEHAVIORAL NEUROSCIENCE
(2023)
Article
Clinical Neurology
Ming-Chang Chiang, Hsueh-Wen Hsueh, Ti-Yen Yeh, Ya-Yin Cheng, Yi-Hui Kao, Kai-Chieh Chang, Fang-Ping Feng, Chi-Chao Chao, Sung-Tsang Hsieh
Summary: This study found that there were changes in cortical excitability within the left primary motor cortex in patients with polyneuropathy, and these changes were associated with neuropathic pain and sensory symptoms.
EUROPEAN JOURNAL OF NEUROLOGY
(2022)
Review
Biochemistry & Molecular Biology
Martina Morchio, Emanuele Sher, David A. Collier, Daniel W. Lambert, Fiona M. Boissonade
Summary: Neuropathic pain is a highly prevalent condition that affects approximately 8% of the adult population in the UK. The underlying pathophysiology is complex and involves various processes, such as altered neuronal excitability, dysregulated intracellular signaling, and activation of immune and glial cells. Over the past 15 years, miRNAs have emerged as important regulators in neuropathic pain development, acting through the modulation of mRNA translation. Animal studies have identified several miRNAs involved in different stages of nociceptive pathways, but the translation of these findings to human subjects with neuropathic pain is still limited and dependent on the specific etiology. Further research using human tissue and liquid samples may provide valuable insights into miRNAs as diagnostic biomarkers or potential therapeutic targets for neuropathic pain.
Article
Anesthesiology
Didier Bouhassira, Serge Perrot, Thibault Riant, Gaelle Martine-Fabre, Gisele Pickering, Caroline Maindet, Nadine Attal, Stephanie Ranque Garnier, Jean-Paul Nguyen, Emmanuelle Kuhn, Eric Viel, Patrick Kieffert, Thomas Toelle, Claire Delorme, Rodrigue Deleens, Patrick Ginies, Virginie Corand-Dousset, Clemence Dal-Col, Alain Serrie, Emmanuel Chevrillon, Christian Gov, Juan Fernando Ramirez-Gil, Cecile Delval, Manuella Schaller, Baptiste Bessiere, Patrick Houeto, Claudia Sommer
Summary: Nitrous oxide (N2O) is commonly used for anesthesia and short-duration analgesia. Research suggests that N2O/O-2 50%-50% mixture can induce long-lasting analgesic effects. A study on chronic peripheral neuropathic pain patients showed that a 1-hour administration of EMONO significantly improved evoked pain intensity and overall impression of change, with effects lasting up to 4 weeks after treatment.
Article
Multidisciplinary Sciences
Sergio Lerma-Lara, Marina De Cherade Montbron, Mathias Guerin, Ferran Cuenca-Martinez, Roy La Touche
Summary: This study found no significant between-group differences in sensorimotor outcomes. A single session of tDCS in isolation appears to produce immediate effects in healthy participants on sensorimotor function; however, these effects were very small.
SCIENTIFIC REPORTS
(2021)
Article
Anesthesiology
Mimmi Gillving, Dyveke Demant, Jakob Holbech, Lene Vase, Flemming W. Bach, Troels S. Jensen, Nanna B. Finnerup, Soren H. Sindrup
Summary: This study aimed to investigate whether the variability in baseline pain levels would influence the placebo response. The results showed that the variability in baseline pain did not have a significant impact on the placebo response.
Review
Biochemistry & Molecular Biology
Eleonora Balzani, Andrea Fanelli, Valentina Malafoglia, Michael Tenti, Sara Ilari, Annette Corraro, Carolina Muscoli, William Raffaeli
Summary: Understanding neuropathic pain presents challenges due to its complex pathophysiological classification mechanisms and the lack of effective diagnostic tools, with treatment responses often unpredictable. The rise of personalized treatments further adds to the complexity of classification.
Article
Neurosciences
Fiona Werland, Michael Hirth, Roman Rukwied, Matthias Ringkamp, Brian Turnquist, Ellen Jorum, Barbara Namer, Martin Schmelz, Otilia Obreja
Summary: Through extracellular single-fibre recordings in pigs, it was found that nerve growth factor can increase the peak following frequency specifically in sensitized mechano-insensitive nociceptors, while having minimal impact on other types of nociceptors.
JOURNAL OF PHYSIOLOGY-LONDON
(2021)
Article
Anesthesiology
Kiran Kumar Bali, Jagadeesh Gandla, Daniel Rojas Rangel, Laura Castaldi, Peter Mouritzen, Nitin Agarwal, Martin Schmelz, Paul Heppenstall, Rohini Kuner
Summary: The study suggests that epigenetic modulation in the form of microRNA (miRNA) expression triggered by metabolic imbalance and nerve damage may regulate the development of pain in painful diabetic peripheral neuropathy. miR-33 and miR-380 expressed in nociceptive neurons are identified as critical factors in diabetic pain, while miR-124-1 is implicated as a mediator of physiological nociception.
Article
Anesthesiology
Fiona Werland, Roberto de Col, Michael Hirth, Brian Turnquist, Martin Schmelz, Otilia Obreja
Summary: UVB irradiation induces mechanical sensitization of primary nociceptors, contributing to primary hyperalgesia, while different responses in nociceptors and mechanosensitive neurons suggest complex mechanisms underlying abnormal pain after sunburn.
Article
Medicine, General & Internal
Emanuel Fryk, Josefin Olausson, Karin Mossberg, Lena Strindberg, Martin Schmelz, Helen Brogren, Li-Ming Gan, Silvano Piazza, Alessandro Provenzani, Barbara Becattini, Lars Lind, Giovanni Solinas, Per-Anders Jansson
Summary: The study suggests that in obese individuals, hyperinsulinemia is mainly caused by elevated free fatty acids, which is a significant factor in the development of insulin resistance in obesity. Additionally, obese subjects with normal glycemia do not show significant differences in lipolysis compared to lean individuals.
Letter
Anesthesiology
Martin Schmelz
Review
Medicine, General & Internal
Martin Schmelz
Summary: Recent research findings challenge the traditional view of itch mechanistic theories as mutually exclusive, suggesting that a combination of factors such as neuronal specificity, temporal patterns, and spatial aspects play a role in itch sensation. Understanding the blend of these factors could provide better insights into chronic itch and improve treatment options.
FRONTIERS IN MEDICINE
(2021)
Article
Neurosciences
Veronica Bonalume, Lucia Caffino, Luca F. Castelnovo, Alessandro Faroni, Sheng Liu, Jing Hu, Marco Milanese, Giambattista Bonanno, Kyra Sohns, Tal Hoffmann, Roberto De Col, Martin Schmelz, Fabio Fumagalli, Valerio Magnaghi, Richard Carr
Summary: The study shows that GABA depolarizes sural nerve axons and increases the electrical excitability of C-fibres via GABA(A) receptor. NKCC1 plays a role in maintaining intra-axonal chloride to stabilize C-fibre excitability. Activation of GABA(A) receptor can stabilize C-fibre excitability during sustained firing.
JOURNAL OF PHYSIOLOGY-LONDON
(2021)
Letter
Anesthesiology
Jan Vollert, Martin Schmelz
Article
Clinical Neurology
Lars Kristian Lunden, Inge Petter Kleggetveit, Martin Schmelz, Ellen Jorum
Summary: This study aimed to investigate the differences in pain characteristics among subgroups of CRPS patients based on quantitative sensory testing (QST) results. Three subgroups were identified based on thermal thresholds, and the presence of thermal allodynia was associated with a higher prevalence of paroxysmal pain. The study suggests that cold allodynia may be related to hyper-excitability of superficial skin nociceptors, and small fiber degeneration alone may not explain the pain mechanism in CRPS.
SCANDINAVIAN JOURNAL OF PAIN
(2022)
Article
Neurosciences
Manuel Pedro Pereira, Martin Schmelz, Sonja Staender
Summary: Neuropathic pruritus conditions result from damage to the nervous system, and novel findings strengthen the specificity theory of pruritus transmission. Activation of nociceptors and specific discharge patterns of primary afferents also contribute to itch development. Interactions between excitatory and inhibitory interneurons, non-neuronal cells, and descending modulation from upper centers contribute to neuronal sensitization, leading to chronic itch and accompanying phenomena.
CURRENT OPINION IN NEUROBIOLOGY
(2022)
Article
Dermatology
M. Dehghan Nayyeri, M. Missler, R. Ritterbach, B. Sundermann, N. Wulms, A. Sueer, M. Dugas, M. P. Pereira, S. Staender, M. Schmelz, B. Pfleiderer
Summary: This study found decreased functional connectivity within the DMN in patients with BRP during rest. In contrast, there were no significant differences in functional connectivity at rest between AD patients and healthy controls.
JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY AND VENEREOLOGY
(2022)
Article
Dermatology
Konstantin Agelopoulos, Lina Renkhold, Henning Wiegmann, Martin Dugas, Aysenur Suer, Claudia Zeidler, Martin Schmelz, Manuel P. Pereira, Sonja Staender
Summary: This study aimed to link gene expression, DNA methylation, and neuroanatomy in different chronic pruritis conditions. Results showed that specific signatures of gene expression and DNA methylation distinguished pruritic lesional skin from nonpruritic skin and healthy skin. Neuroanatomy analysis revealed differential branching patterns among the different conditions, indicating that chronic itching conditions are primarily caused by nerve injury and subsequent sprouting, while genuine neuropathy is expected in brachioradial pruritus.
JOURNAL OF INVESTIGATIVE DERMATOLOGY
(2023)
Article
Clinical Neurology
Martin Schmelz
Summary: Quantitative sensory testing (QST) has been optimized for diagnosing small fiber neuropathy, but current sensory phenotypes cannot successfully stratify neuropathy patients with and without pain.
SCANDINAVIAN JOURNAL OF PAIN
(2022)
Article
Multidisciplinary Sciences
Michael Neumaier, Sophie Giesler, Volker Ast, Mathis Roemer, Timo-Daniel Voss, Eileen Reinz, Victor Costina, Martin Schmelz, Elina Nuernberg, Stefanie Nittka, Aino-Maija Leppae, Ruediger Rudolf, Andreas Trumpp, Tina Fuchs
Summary: This report introduces a new class of innate immune cells, called VIREMs, which are myeloid cells unrelated to lymphocytes. The researchers found that B-VIREMs, a subtype of VIREMs, have the ability to genetically recombine and express antibody genes, similar to B lymphocytes. They also discovered that B-VIREMs circulate in the blood of healthy individuals and undergo clonal expansion in response to disease stimuli. Live-cell imaging models suggest that B-VIREMs load their own Fc receptors with endogenous antibodies during vesicle transport. The findings suggest that these innate immune cells have important antigen-specific tissue maintenance functions.
