I am a
Home I AM A Search Login

Accepted

Share this

Derivation of peripheral nociceptive, mechanoreceptive, and proprioceptive sensory neurons from the same culture of human pluripotent stem cells.

The three peripheral sensory neuron (SN) subtypes, nociceptors, mechanoreceptors, and proprioceptors, localize to dorsal root ganglia and convey sensations such as pain, temperature, pressure, and limb movement/position. Despite previous reports, to date no protocol is available allowing the generation of all three SN subtypes at high efficiency and purity from human pluripotent stem cells (hPSCs). We describe a chemically defined differentiation protocol that generates all three SN subtypes from the same starting population, as well as methods to enrich for each individual subtype. The protocol yields high efficiency and purity cultures that are electrically active and respond to specific stimuli. We describe their molecular character and maturity stage and provide evidence for their use as an axotomy model; we show disease phenotypes in hPSCs derived from patients with familial dysautonomia. Our protocol will allow the modeling of human disorders affecting SNs, the search for treatments, and the study of human development.

Learn More >

A proteome signature in dorsal root ganglia for acute incisional pain in mice.

After surgery, acute pain is still managed insufficiently and may lead to short- and long-term complications including chronic postsurgical pain and an increased prescription of opioids. Thus, identifying new targets specifically implicated in postoperative pain is of utmost importance to develop effective and non-addictive analgesics. Here, we employed an integrated and multimethod workflow to reveal unprecedented insights into proteome dynamics in dorsal root ganglia (DRG) of mice after plantar incision (INC). Based on a detailed characterization of INC-associated pain-related behavior profiles, including a novel paradigm for non-evoked pain (NEP), we performed quantitative mass-spectrometry-based proteomics in DRG 1 day after INC. Our data revealed a hitherto unknown INC-regulated protein signature in DRG with changes in distinct proteins and cellular signaling pathways. In particular, we show the differential regulation of 44 protein candidates, many of which are annotated with pathways related to immune and inflammatory responses such as MAPK/ERK signaling. Subsequent orthogonal assays comprised multiplex western blotting, bioinformatic protein network analysis, and immunolabeling in independent mouse cohorts to validate (i) the INC-induced regulation of immune/inflammatory pathways and (ii) the high priority candidate Annexin A1 (Anxa1). Taken together, our results propose novel potential targets in the context of incision and, therefore, represent a highly valuable resource for further mechanistic and translational studies of postoperative pain.

Learn More >

Classification algorithm for the ICD-11 chronic pain classification (CAL-CP): development and results from a preliminary pilot evaluation.

The ICD-11 chronic pain classification includes about 100 chronic pain diagnoses on different diagnostic levels. Each of these diagnoses requires specific operationalized diagnostic criteria to be present. The classification comprises more than 200 diagnostic criteria. The aim of the Classification Algorithm for Chronic Pain in ICD-11 (CAL-CP) is to facilitate the use of the classification by guiding users through these diagnostic criteria. The diagnostic criteria were ordered hierarchically and visualized in accordance with the standards defined by the Society for Medical Decision Making Committee on Standardization of Clinical Algorithms. The resulting linear decision tree underwent several rounds of iterative checks and feedback by its developers, as well as other pain experts. A preliminary pilot evaluation was conducted in the context of an ecological implementation field study of the classification itself. The resulting algorithm consists of a linear decision tree, an introduction form, and an appendix. The initial decision trunk can be used as stand-alone algorithm in primary care. Each diagnostic criterion is represented in a decision box. The user needs to decide for each criterion whether it is present or not, and then follow the respective yes or no arrows to arrive at the corresponding ICD-11 diagnosis. The results of the pilot evaluation showed good clinical utility of the algorithm. The CAL-CP can contribute to reliable diagnoses by structuring a way through the classification and by increasing adherence to the criteria. Future studies need to evaluate its utility further and analyze its impact on the accuracy of the assigned diagnoses.

Learn More >

Gray Matter Volume Differences Between More Versus Less Resilient Adults with Chronic Musculoskeletal Pain: A Voxel-Based Morphology Study.

Resilience, a personality construct that reflects capacities to persevere, maintain a positive outlook and/or thrive despite ongoing stressors, has emerged as an important focus of research on chronic pain (CP). Although behavior studies have found more resilient persons with CP experience less pain-related dysfunction than less resilient cohorts do, the presence and nature of associated brain structure differences has received scant attention. To address this gap, we examined gray matter volume (GMV) differences between more versus less resilient adults with chronic musculoskeletal pain. Participants (75 women, 43 men) were community-dwellers who reported ongoing musculoskeletal pain for at least three months. More (n = 57) and less (n = 61) resilient subgroups, respectively, were identified on the basis of scoring above and below median scores on two validated resilience questionnaires. Voxel-based morphology (VBM) undertaken to examine resilience subgroup differences in GMV indicated more resilient participants displayed significantly larger GMV in the (1) bilateral precuneus, (2) left superior and inferior parietal lobules, (3) orbital right middle frontal gyrus and medial right superior frontal gyrus, and (4) bilateral median cingulate and paracingulate gyri, even after controlling for subgroup differences on demographics and measures of pain-related distress. Together, results underscored the presence and nature of specific GMV differences underlying subjective reports of more versus less resilient responses to ongoing musculoskeletal pain.

Learn More >

Validity and reliability of Patient-Reported Outcomes Measurement Information System Global Health scale in adults with atopic dermatitis.

Patient-Reported Outcomes Measurement Information System Global Health (PGH) was validated to assess health-related quality of life (HRQOL) in several diseases. Little is known about its measurement properties in adult atopic dermatitis (AD).

Learn More >

High-Dose Spinal Cord Stimulation Reduces Long-Term Pain Medication Use in Patients With Failed Back Surgery Syndrome Who Obtained at Least 50% Pain Intensity and Medication Reduction During a Trial Period: A Registry-Based Cohort Study.

High-dose spinal cord stimulation (HD-SCS) revealed positive results for obtaining pain relief in patients with failed back surgery syndrome (FBSS). However, it is less clear whether HD-SCS also is able to reduce pain medication use. The aim of this registry-based cohort study is to explore the impact of HD-SCS on pain medication use in FBSS patients.

Learn More >

Insights into the Irritating Mechanisms of TRPA1 Revealed by Cryo-EM.

TRPA1 is a promising target for the development of novel treatments for chronic pain. In this issue of Neuron, Liu et al. (2021) report a novel non-covalent TRPA1-biased agonist, GNE551, revealing a unique binding pocket by cryo-EM and activation properties that pave a path toward new avenues in the treatment of chronic pain.

Learn More >

Peripheral receptors and neuromediators involved in the antihyperalgesic effects of acupuncture: a state-of-the-art review.

The present study aims to describe state-of-the-art of preclinical studies that have investigated peripheral receptors and neuromediators involved in the antihyperalgesic effects of acupuncture. The PubMed, Scopus, and Web of Science databases were searched using the integrative review method. Preclinical articles that involved the study of peripheral receptors and neuromediators on the pain control effects of acupuncture in rats or mice were selected using a predefined search strategy. From this search, 456 articles were found, and 29 of them met the inclusion criteria of the study. The selected articles addressed the following peripheral receptors: opioid (n = 9), adenosine (n = 5), cannabinoid (n = 5), transient receptor potential vanilloid (TRPV) (n = 3), histamine (n = 2), adrenergic (n = 1), muscarinic (n = 1), corticotrophin-releasing factor (CRF) (n = 2), IL-1 (n = 1), and endothelin (n = 1) receptors. The peripheral neuromediators correlated with the peripheral pain control effect were as follows: opioid peptides (n = 4), adenosine (n = 3), histamine (n = 1), substance P (n = 1) calcitonin gene-related peptide (CGRP) (n = 1), anandamide (n = 1), nitric oxide (n = 1), and norepinephrine (n = 1). This review summarizes the methods used to investigate the peripheral effects of acupuncture and discusses the main findings on each family of receptors and neuromediators. Ten families of peripheral receptors and 8 types of neuromediators were correlated with the antihyperalgesic effects of acupuncture in preclinical studies. Considering the benefits of a better understanding of the role of peripheral receptors and neuromediators in the context pain management, the findings of the present study highlight the importance of deepening the exploration of the peripheral mechanisms of acupuncture.

Learn More >

Which Exercise for Low Back Pain? (WELBack) trial predicting response to exercise treatments for patients with low back pain: a validation randomised controlled trial protocol.

Exercise therapy is the most recommended treatment for chronic low back pain (LBP). Effect sizes for exercises are usually small to moderate and could be due to the heterogeneity of people presenting with LBP. Thus, if patients could be better matched to exercise based on individual factors, then the effects of treatment could be greater. A recently published study provided evidence of better outcomes when patients are matched to the appropriate exercise type. The study demonstrated that a 15-item questionnaire, the Lumbar Spine Instability Questionnaire (LSIQ), could identify patients who responded best to one of the two exercise approaches for LBP (motor control and graded activity). The primary aim of the current study isill be to evaluate whether preidentified baseline characteristics, including the LSIQ, can modify the response to two of the most common exercise therapies for non-specific LBP. Secondary aims include an economic evaluations with a cost-effectiveness analysis.

Learn More >

Prevalence of pre-cluster symptoms in episodic cluster headache: Is it possible to predict an upcoming bout?

Early symptoms prior to a cluster headache bout have been reported to occur days or weeks before the actual beginning of the cluster headache bouts. This study aimed to describe the prevalence of pre-cluster (premonitory) symptoms and examine the predictability of an upcoming cluster headache bout.

Learn More >

Search