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The Journal of Pain Nov 2023Social context has been shown to influence pain perception. This study aimed to broaden this literature by investigating whether relevant social stimuli, such as faces...
Social context has been shown to influence pain perception. This study aimed to broaden this literature by investigating whether relevant social stimuli, such as faces with different levels of intrinsic (based on physical resemblance to known individuals) and episodic (acquired through a previous experience) familiarity, may lead to hypoalgesia. We hypothesized that familiarity, whether intrinsic or acquired through experience, would increase pain threshold and decrease pain intensity. Sixty-seven participants underwent pain induction (the cold pressor test) viewing previously seen faces (Episodic Group) or new faces (Non-episodic Group) that differed in the level of intrinsic familiarity (high vs low). Pain threshold was measured in seconds, while pain intensity was measured on a rating scale of 0 to 10. The results did not show an effect of episodic familiarity. However, compared to low, high intrinsic familiar faces had an attenuating effect on pain intensity, even after controlling for pain expectation. These results suggest that physical features conveying a higher feeling of familiarity induce a top-down hypoalgesic modulation, in line with the idea that familiarity may signal safety and that the presence of familiar others reduce perceived threat-related distress. This study provides further evidence on the social modulation of pain and contributes to the literature on first impressions' influence on social behavior. PERSPECTIVE: Consistent with the idea that familiar others signal safety and reduce the sense of threat, facial features conveying familiarity induce a top-down hypoalgesic modulation. This knowledge may contribute to understanding differences in pain perception in experimental and clinical contexts.
Topics: Humans; Recognition, Psychology; Pain; Pain Perception
PubMed: 37356606
DOI: 10.1016/j.jpain.2023.06.012 -
Journal of Integrative Neuroscience Jul 2023Chronic pain refers to pain that persists for over three months. Chronic pain may restrict activities of daily living, including work, learning, social life, and can...
BACKGROUND
Chronic pain refers to pain that persists for over three months. Chronic pain may restrict activities of daily living, including work, learning, social life, and can lead to anxiety, depression, and sleep disturbance. Imaging data have demonstrated that central sensitization often occurs in the brain of patients with chronic pain, which arises from imbalanced neurotransmission in the central nervous system. Transient receptor potential vanilloid 1 (TRPV1) is an ion channel to serve as an inflammatory detector in the brain. We aim to determine the properties of acupoint catgut embedding (ACE) on cold stress-induced mice fibromyalgia (FM) and surveyed the character of TRPV1 and linked molecules in chronic FM pain.
METHODS
Intermittent cold stress (ICS) was used to induce mice FM model. Mice were subgrouped into normal mice, ICS-induced FM group, FM mice with ACE, and FM in group. ACE is a novel acupuncture technique that provides convenience and continuous nerve stimulation that has been reported effective on pain management.
RESULTS
Our behavioral experiments showed similar levels of pain response among all groups before treatment. After ICS, prolonged mechanical and thermal pain was initiated (mechanical threshold: 1.96 ± 0.12 g; thermal latency: 4.86 ± 0.21 s) and were alleviated by ACE treatment and gene deletion. Inflammatory mediators were increased in the plasma of FM mice, while TRPV1 and related kinases were amplified in the hypothalamus and cerebellum. These changes were ameliorated in the ACE-treated and groups.
CONCLUSIONS
These novel findings suggest that chronic FM pain can be modulated by ACE or gene deletion. The analgesic effect of ACE through the TRPV1 pathway may reflect its potential as a therapeutic target for FM treatment.
Topics: Animals; Mice; Activities of Daily Living; Acupuncture Points; Brain; Catgut; Chronic Pain; Fibromyalgia; TRPV Cation Channels
PubMed: 37519181
DOI: 10.31083/j.jin2204097 -
Pain Reports 2023Chronotype indicates the biological preference for timing of activity and sleep. Being a late chronotype (ie, having a tendency for late sleep times) is associated with...
INTRODUCTION
Chronotype indicates the biological preference for timing of activity and sleep. Being a late chronotype (ie, having a tendency for late sleep times) is associated with several mental and physical health problems. Previous studies found that late chronotypes are also more susceptible to chronic pain, but the relationship between chronotype and pain sensitivity remains unclear.
OBJECTIVES
The aim of this study was to investigate the relationship between chronotype and heat pain threshold (as an indicator of pain sensitivity) in a sample of young healthy adults.
METHODS
We analyzed data from 316 young healthy adults participating in 4 different studies run at the Medical Faculty of the University of Augsburg. In all studies, chronotype and other sleep variables (eg, sleep duration) were assessed using the micro Munich ChronoType Questionnaire. Heat pain threshold was assessed with the method of adjustment.
RESULTS
Chronotype was not significantly associated with the heat pain threshold. Entering the other sleep variables in separate regression models did also not significantly explain variance in heat pain threshold.
CONCLUSION
Our null findings are in contrast with previous notions that late chronotypes might be more sensitive to pain and more susceptible to chronic pain. Given the scarcity of the literature on this topic, more studies are needed to clarify the relationship between chronotype and pain sensitivity in different age populations, while also considering distinct pain modalities or other types of pain tests.
PubMed: 37358936
DOI: 10.1097/PR9.0000000000001085 -
Scandinavian Journal of Pain Jul 2023The objective of this longitudinal cohort study was to investigate if preoperative pain mechanisms, anxiety, and depression increase risk of developing chronic...
OBJECTIVES
The objective of this longitudinal cohort study was to investigate if preoperative pain mechanisms, anxiety, and depression increase risk of developing chronic post-thoracotomy pain (CPTP) after lung cancer surgery.
METHODS
Patients with suspected or confirmed lung cancer undergoing surgery by either video-assisted thoracoscopic surgery or anterior thoracotomy were recruited consecutively. Preoperative assessments were conducted by: quantitative sensory testing (QST) (brush, pinprick, cuff pressure pain detection threshold, cuff pressure tolerance pain threshold, temporal summation and conditioned pain modulation), neuropathic pain symptom inventory (NPSI), and the Hospital Anxiety and Depression Scale (HADS). Clinical parameters in relation to surgery were also collected. Presence of CPTP was determined after six months and defined as pain of any intensity in relation to the operation area on a numeric rating scale form 0 (no pain) to 10 (worst pain imaginable).
RESULTS
A total of 121 patients (60.2 %) completed follow-up and 56 patients (46.3 %) reported CPTP. Development of CPTP was associated with higher preoperative HADS score (p=0.025), higher preoperative NPSI score (p=0.009) and acute postoperative pain (p=0.042). No differences were observed in relation to preoperative QST assessment by cuff algometry and HADS anxiety and depression sub-scores.
CONCLUSIONS
High preoperative HADS score preoperative pain, acute postoperative pain intensity, and preoperative neuropathic symptoms were was associated with CPTP after lung cancer surgery. No differences in values of preoperative QST assessments were found. Preoperative assessment and identification of patients at higher risk of postoperative pain will offer opportunity for further exploration and development of preventive measures and individualised pain management depending on patient risk profile.
Topics: Humans; Prospective Studies; Thoracotomy; Longitudinal Studies; Pain Measurement; Chronic Pain; Lung Neoplasms; Risk Factors; Pain, Postoperative
PubMed: 37327358
DOI: 10.1515/sjpain-2023-0016 -
Age and Ageing May 2024Pain sensitivity varies across multimodal somatosensory stimuli that can rely on different conductive fibres, which, when damaged, will lead to neuropathies. However,... (Comparative Study)
Comparative Study
BACKGROUND
Pain sensitivity varies across multimodal somatosensory stimuli that can rely on different conductive fibres, which, when damaged, will lead to neuropathies. However, there is limited research examining the characteristics of perceived pain, particularly as affected by the ageing process, as induced by various somatosensory stimuli that may rely on small or large fibres.
METHODS
Using heat and pressure stimuli on small and large fibres separately on both younger and older adults, this study examined age-associated changes in pain perception by measuring self-reported pain sensitivity, pain threshold and pain discriminability.
RESULTS
Heat pain threshold was significantly positively correlated with age, but not pressure pain threshold. Pain threshold increased and pain discriminability decreased in response to heat stimuli in the older participants compared with the younger ones.
CONCLUSION
An age-associated decline in heat pain perception was observed, suggesting an earlier degradation of heat perception. These findings provide new insight into understanding and assessing somatosensory disorders, which can help ageing populations better maintain healthy sensory functioning.
Topics: Humans; Pain Threshold; Aged; Male; Pain Perception; Female; Aging; Age Factors; Adult; Hot Temperature; Pain Measurement; Young Adult; Middle Aged; Pressure; Aged, 80 and over
PubMed: 38776215
DOI: 10.1093/ageing/afae107 -
Osteoarthritis and Cartilage Dec 2023TissueGene-C (TG-C), a combination of human allogeneic chondrocytes and irradiated GP2-293 cells engineered to overexpress transforming growth factor-β1 (TGF-β1), has...
TissueGene-C induces long-term analgesic effects through regulation of pain mediators and neuronal sensitization in a rat monoiodoacetate-induced model of osteoarthritis pain.
OBJECTIVE
TissueGene-C (TG-C), a combination of human allogeneic chondrocytes and irradiated GP2-293 cells engineered to overexpress transforming growth factor-β1 (TGF-β1), has been developed as a novel cell-based gene therapy and a candidate for disease modifying osteoarthritis drug (DMOAD). We aim to investigate analgesic mechanism of TG-C in a pre-clinical animal model with monoiodoacetate (MIA)-induced pain.
DESIGN
We used a rat MIA model of osteoarthritis (OA) pain. We examined that TG-C can regulate pain by inhibiting the upregulation of various pain mediators in both knee joint tissue and dorsal root ganglia (DRG) (n = 112) and alleviating pain behavior (n = 41) and neuronal hyperexcitability in DRG (n = 60), afferent nerve fiber (n = 24), and spinal cord (n = 35).
RESULTS
TG-C significantly alleviated pain-related behavior by restoring altered dynamic weight bearing and reduced mechanical threshold of the affected hindlimb. TG-C significantly suppressed the expression of nerve growth factor (NGF) and calcitonin gene-related peptide (CGRP) in inflamed joint tissue. TG-C significantly suppressed the upregulation of tropomyosin receptor kinase A (TrkA) and nerve injury/regeneration protein (GAP43) and activation of Iba1-positive microglial cells in DRG. TG-C significantly recovered neuronal hyperexcitability by restoring RMP and firing threshold and frequency of DRG neurons, attenuating firing rates of mechanosensitive C- or Aδ-nerve fiber innervating knee joint, and lowering increased miniature and evoked excitatory postsynaptic currents (mEPSCs and eEPSCs) in the spinal cord.
CONCLUSION
Our results demonstrated that TG-C exerted potent analgesic effects in a rat MIA model of OA pain by inhibiting the upregulation of pain mediators and modulating neuronal sensitization.
Topics: Rats; Humans; Animals; Rats, Sprague-Dawley; Pain; Osteoarthritis; Analgesics; Neurons; Ganglia, Spinal; Disease Models, Animal
PubMed: 37544583
DOI: 10.1016/j.joca.2023.07.008 -
Communications Biology Oct 2023The Nav1.7 voltage-gated sodium channel plays a key role in nociception. Three functional variants in the SCN9A gene (encoding M932L, V991L, and D1908G in Nav1.7), have...
The Nav1.7 voltage-gated sodium channel plays a key role in nociception. Three functional variants in the SCN9A gene (encoding M932L, V991L, and D1908G in Nav1.7), have recently been identified as stemming from Neanderthal introgression and to associate with pain symptomatology in UK BioBank data. In 1000 genomes data, these variants are absent in Europeans but common in Latin Americans. Analysing high-density genotype data from 7594 Latin Americans, we characterized Neanderthal introgression in SCN9A. We find that tracts of introgression occur on a Native American genomic background, have an average length of ~123 kb and overlap the M932L, V991L, and D1908G coding positions. Furthermore, we measured experimentally six pain thresholds in 1623 healthy Colombians. We found that Neanderthal ancestry in SCN9A is significantly associated with a lower mechanical pain threshold after sensitization with mustard oil and evidence of additivity of effects across Nav1.7 variants. Our findings support the reported association of Neanderthal Nav1.7 variants with clinical pain, define a specific sensory modality affected by archaic introgression in SCN9A and are consistent with independent effects of the Neanderthal variants on Nav1.7 function.
Topics: Humans; Animals; Pain Threshold; Neanderthals; Pain; NAV1.7 Voltage-Gated Sodium Channel; Nociception
PubMed: 37816865
DOI: 10.1038/s42003-023-05286-z -
Psychiatria Danubina 2023Pain is one of the basic defense responses of living organisms. Although the threshold for pain perception varies from person to person, there is no doubt that pain... (Review)
Review
INTRODUCTION
Pain is one of the basic defense responses of living organisms. Although the threshold for pain perception varies from person to person, there is no doubt that pain reduces a person's quality of life. Assessing the subjective experience of pain is especially important in the treatment of patients with schizophrenia. In light of recent advances in neuroscience, we discuss pain thresholds in patients with schizophrenia.
METHODS
A narrative review of pain thresholds in patients with schizophrenia was conducted. We electronically searched the PubMed and Google Scholar databases for articles in English with "pain," "schizophrenia," "neural circuits," and "neurotransmitters" in the title or abstract, for the period January 2000 through June 2022.
RESULTS
A seemingly contradictory phenomenon has been noted with regard to pain thresholds in patients with schizophrenia. One phenomenon is a high pain threshold for nociceptive stimuli, and the other is a low pain threshold in chronic pain. As a result, a pain threshold paradox has been observed.
CONCLUSIONS
Many schizophrenia patients appear to have an excess of dopamine in the mesolimbic system, which stimulates both the descending pain inhibitory pathway and the salience network. As a result, a pain threshold paradox has been observed, in which the threshold for acute nociceptive pain is high and the threshold for chronic pain is low.
Topics: Humans; Pain Threshold; Chronic Pain; Quality of Life; Schizophrenia; Pain Perception
PubMed: 37480304
DOI: 10.24869/psyd.2023.174 -
Pain Management Nursing : Official... Aug 2023Post-stroke pain in patients with an inability to communicate is not systematically assessed and therefore not sufficiently treated. This stresses the need to study pain...
BACKGROUND
Post-stroke pain in patients with an inability to communicate is not systematically assessed and therefore not sufficiently treated. This stresses the need to study pain assessment instruments that do not require good communication skills.
AIM
To examine the validity and reliability of the Pain Assessment Checklist for Seniors with Limited Ability to Communicate - Dutch version (PACSLAC-D) in stroke patients with aphasia.
METHOD
Sixty stroke patients (mean age 79.3 years, standard deviation [SD] 8.0), of whom 27 had aphasia were observed during rest, activities of daily living (ADL), and physiotherapy using the Pain Assessment Checklist for Seniors with Limited Ability to Communicate - Dutch version (PACSLAC-D). The observations were repeated after two weeks. To examine convergent validity, correlations between the PACSLAC-D, self-report pain scales, and the clinical judgment of a health care professional (pain present yes/no) were used. To examine discriminative validity, differences in pain were investigated between rest and ADL, in patients who use pain medication and those who do not, and in patients with and without aphasia. Internal consistency and test-retest reliability were assessed to determine reliability.
RESULTS
Convergent validity failed to meet the acceptable threshold during rest but was adequate during ADL and physiotherapy. Discriminative validity was only adequate during ADL. The internal consistency was 0.33 during rest, 0.71 during ADL, and 0.65 during physiotherapy. Test-retest reliability varied from poor during rest (intraclass correlation coefficient [ICC] = 0.07; 95% confidence interval [CI]: -0.40-0.51) to excellent during physiotherapy (ICC = 0.95; 95% CI: 0.83-0.98).
CONCLUSIONS
The PACSLAC-D captures pain in patients with aphasia who are unable to self-report, during ADL and physiotherapy, but may be less accurate during rest.
Topics: Humans; Aged; Dementia; Reproducibility of Results; Activities of Daily Living; Aphasia; Pain; Psychometrics; Surveys and Questionnaires
PubMed: 37100703
DOI: 10.1016/j.pmn.2023.03.010 -
Journal of Ethnopharmacology Apr 2024Bushen Zhuangjin Decoction (BZD) are an herbal compound commonly used to treat osteoarthritis (OA) in China.
ETHNOPHARMACOLOGICAL RELEVANCE
Bushen Zhuangjin Decoction (BZD) are an herbal compound commonly used to treat osteoarthritis (OA) in China.
AIM OF THE STUDY
This study aimed to verify the mechanism of Bushen Zhuangjin Decoction in relieving the pain of knee osteoarthritis.
MATERIALS AND METHODS
Network pharmacology evaluation was used to discover the potential targets of BZD to relieve pain in KOA. The therapeutic effects of BZD treatment on KOA pain using histomorphology, behavioral assessments, suspension chip analysis, and ultra-high performance liquid chromatography/tandem mass spectrometry (UHPLC-MS/MS) assays. The functional magnetic resonance imaging was used to explore the effects of BZD treatment on brain function associated to KOA.
RESULTS
Network pharmacological analysis revealed the association between the analgesic effect of BZD on KOA and the pain signaling neurotransmitter 5-HT. Subsequently, we conducted experiments to verify the therapeutic effect of BZD on pain in KOA animal models. Behavioral tests demonstrated that the pain threshold of knee osteoarthritis rats decreased in PWT and PWL, but BZD was able to increase the pain threshold. Histopathological staining indicated thinning of the cartilage layer and sparse trabeculae in the subchondral bone. Suspension chip analysis revealed a significant increase in pro-inflammatory factors of IL-1α, IL-5, IL-12, IL-17A, RANTES, TNF-α and M-CSF in KOA, along with a significant decrease in anti-inflammatory factor of IL-13. However, BZD treatment decreased the expression of pro-inflammatory factors and increased the content of anti-inflammatory factor. UHPLC-MS/MS analysis showed a significant decrease in the serum levels of GABA, E, GSH, Kyn, Met, and VMA in KOA, which were significantly increased by BZD. Conversely, the serum levels of TrpA, TyrA, Spd, and BALa were significantly increased in KOA and significantly decreased by BZD. ELISA and Western blot analysis showed increased expression of subchondral bone pain-related neuropeptides SP, CGRP, TH, NPY, VEGFA, 5-HT3 in KOA, which were decreased in BZD. Functional magnetic resonance imaging demonstrated that BZD exerts its therapeutic effect on KOA by modulating the activity and functional connections of the cortex, hypothalamus, and hippocampus.
CONCLUSIONS
This study confirmed the significant role of pain-related neuromodulation mechanisms in the analgesic therapy of BZD and provides a theoretical foundation for using BZD as a traditional Chinese medical treatment for KOA pain.
Topics: Rats; Animals; Osteoarthritis, Knee; Tandem Mass Spectrometry; Pain; Analgesics; Anti-Inflammatory Agents; Drugs, Chinese Herbal
PubMed: 38266947
DOI: 10.1016/j.jep.2024.117772