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Frontiers in Neuroscience 2022Sensory corpuscles, or cutaneous end-organ complexes, are complex structures localized at the periphery of Aβ-axon terminals from primary sensory neurons that primarily...
Sensory corpuscles, or cutaneous end-organ complexes, are complex structures localized at the periphery of Aβ-axon terminals from primary sensory neurons that primarily work as low-threshold mechanoreceptors. Structurally, they consist, in addition to the axons, of non-myelinating Schwann-like cells (terminal glial cells) and endoneurial- and perineurial-related cells. The terminal glial cells are the so-called lamellar cells in Meissner and Pacinian corpuscles. Lamellar cells are variably arranged in sensory corpuscles as a "coin stack" in the Meissner corpuscles or as an "onion bulb" in the Pacinian ones. Nevertheless, the origin and protein profile of the lamellar cells in both morphotypes of sensory corpuscles is quite similar, although it differs in the expression of mechano-gated ion channels as well as in the composition of the extracellular matrix between the cells. The lamellar cells have been regarded as supportive cells playing a passive role in the process of genesis of the action potential, i.e., the mechanotransduction process. However, they express ion channels related to the mechano-electric transduction and show a synapse-like mechanism that suggest neurotransmission at the genesis of the electrical action potential. This review updates the current knowledge about the embryonic origin, development modifications, spatial arrangement, ultrastructural characteristics, and protein profile of the lamellar cells of cutaneous end-organ complexes focusing on Meissner and Pacinian morphotypes.
PubMed: 35356056
DOI: 10.3389/fnins.2022.790130 -
European Journal of Physical and... Apr 2022The analgesic action of localized vibration (LV), which is used in rehabilitation medicine to treat various clinical conditions, is usually attributed to spinal gate...
INTRODUCTION
The analgesic action of localized vibration (LV), which is used in rehabilitation medicine to treat various clinical conditions, is usually attributed to spinal gate control, but is actually more complex. The aim of this review is: 1) to provide neurophysiological insights into the mechanisms underlying the ways in which afferent activity set up by LV induces analgesia through interactions with the nociceptive system throughout the nervous system; 2) to give a broader vision of the different effects induced by LV, some of them still related to basic science speculation.
EVIDENCE ACQUISITION
The Medline, EMBASE, AMED, Cochrane Library, CINAHL, Web of Science and ROAD databases were searched for animal and human neurophysiological and neurohormonal studies related to the direct effects of LV on nociceptive transmission and pain perception and were supplemented by published books and theses.
EVIDENCE SYNTHESIS
The spinal gate control mechanism through Aβ-fibers activation seems to be the most effective antinociceptive system activated by LV at frequencies between 100 and 250 Hz (high-frequency LV [HF-LV]) when applied in the same segment as the pain. A gating effect can be obtained also when it is applied contralaterally to the painful site or to adjacent dermatomes. Kinesthetic illusions of movement induced by HF-LV may induce a stronger analgesic effect. Activation of C-mechanoreceptors induced by a massage-like LV of low frequency and low intensity may interfere with pain through the activation of the limbic system. This action does not involve any gating mechanism. Frequency is more important than intensity as different frequencies induce activity in different cortical and cerebellar areas; these activations may be related to plastic cortical changes tentatively reversing pain-related maladaptive disorganization. Distraction/shift of attention or cortisol-mediated stress-induced analgesia are not involved in LV analgesic action in humans for both LF and HF. The release of opioidergic neuropeptides (analgesia not reversed by naloxone) as well as a reduction in substance P in the CSF does not seem to play a major role in the HF-LV action. Decrease in calcitonin and TRPV1 expression in the trigeminal ganglia in animals has been induced by HF-LV but the role of LF-LV is not completely deciphered. Both high and low LV induce the release of oxytocin, which may induce antinociceptive responses in animals and contribute to controlling pain in humans.
CONCLUSIONS
Although many aspects of LV-induced pain alleviation deserve more in-depth basic and translational studies, there are sound neurophysiological reasons for using LV in the therapeutic armamentarium of pain control. Laboratory animal and human data indicate that LV relieves pain not only by acting on the spinal gate, but also at higher levels of the nervous system.
Topics: Analgesics; Animals; Humans; Pain; Pain Management; Spine; Vibration
PubMed: 35102735
DOI: 10.23736/S1973-9087.22.07415-9 -
Lin Chuang Er Bi Yan Hou Tou Jing Wai... Jun 2021As one of the neurotrophic factors and insulin family, insulin like growth factor-1(IGF-1) can promote cell synthesis and metabolism in tissues and organs, activate... (Review)
Review
As one of the neurotrophic factors and insulin family, insulin like growth factor-1(IGF-1) can promote cell synthesis and metabolism in tissues and organs, activate cell growth, proliferation and differentiation, and inhibit cell apoptosis. Sensorineural hearing loss is the most common manifestation of the inner ear disease, which is mainly caused by the damage of cochlear hair cells. The lack of IGF-1 directly affects the growth, development and differentiation of cochlear hair cells, thus IGF-1 participates in the maintenance of cell survival and repair during inner ear cell injury. This article systematically reviews the recent research progress on the protective mechanism of IGF-1 on the inner ear.
Topics: Ear, Inner; Hair Cells, Auditory; Hearing Loss, Sensorineural; Humans; Insulin-Like Growth Factor I; Nerve Growth Factors; Spiral Ganglion
PubMed: 34304523
DOI: 10.13201/j.issn.2096-7993.2021.06.020 -
Arthroscopy, Sports Medicine, and... Feb 2021To perform a systematic review to identify macroscopic and microscopic patterns and differences in hip capsule innervation between normal hips and hips with... (Review)
Review
Healthy Hip Joints Have Different Macroscopic and Microscopic Capsular Nerve Architecture Compared With Hips With Osteoarthritis, Femoroacetabular Impingement Syndrome, and Developmental Dysplasia of the Hip: A Systematic Review.
PURPOSE
To perform a systematic review to identify macroscopic and microscopic patterns and differences in hip capsule innervation between normal hips and hips with osteoarthritis (OA), femoroacetabular impingement (FAI) syndrome, and developmental dysplasia of the hip (DDH).
METHODS
A systematic review was performed using Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. Multiple databases were searched for both clinical and basic science laboratory studies on hip capsule innervation. Non-innervation capsule and non-human animal studies were excluded. Macroscopic and microscopic differences in capsular innervation between normal hips, and hips with OA, FAI, and DDH were analyzed. Methodological quality assessment of all studies included in this review was completed using the Methodological Index for Non-randomized Studies.
RESULTS
Ten articles were analyzed (263 specimens; 211 patients, 52 cadavers; mean Methodological Index for Non-randomized Studies 10/16). The hip capsule is innervated by the sciatic and superior gluteal nerves posterosuperiorly, nerve to quadratus femoris and inferior gluteal nerve posteroinferiorly, and femoral and obturator nerves anteriorly. The anterior-superior capsule between 1:00 and 2:30 o'clock on a right hip is a safe internervous zone. The superolateral capsule has the greatest density of mechanoreceptors and sensory fibers. OA is associated with a greater expression of nerve fibers compared with normal hips but does not correlate with pain or disability. No significant differences were found in nerve fiber expression among patients with DDH, FAI, or normal hips. A negative correlation is seen with aging and pain fiber expression.
CONCLUSIONS
The hip capsule has a complex macroscopic and microscopic innervation pattern with varying nerve fiber expression from at least 6 separate peripheral nerves. OA is associated with a greater expression of nerve fibers, although nerve fiber expression does not correlate with painful pathology.
LEVEL OF EVIDENCE
IV, Systematic review of level I-IV studies.
PubMed: 33615274
DOI: 10.1016/j.asmr.2020.08.015 -
Pain Medicine (Malden, Mass.) May 2021The aim of this literature review was to establish consensus with respect to the anatomic features of the articular branches innervating the hip joint and the...
OBJECTIVES
The aim of this literature review was to establish consensus with respect to the anatomic features of the articular branches innervating the hip joint and the distribution of sensory receptors within its capsule.
METHODS
Five electronic databases were queried, with the search encompassing articles published between January 1945 and June 2019. Twenty-one original articles providing a detailed description of sensory receptors around the hip joint capsule (n=13) and its articular branches (n=8) were reviewed.
RESULTS
The superior portions of the anterior capsule and the labrum were found to be the area of densest nociceptive innervation. Similar to the distribution of nociceptors, mechanoreceptor density was found to be higher anteriorly than posteriorly. Hip joint capsular innervation was found to consistently involve the femoral and obturator nerves, which supply the anterior capsule, and the nerve to the quadratus femoris, which supplies the posterior capsule. The femoral, obturator, and superior gluteal nerves supply articular branches to the most nociceptor-rich region of the hip capsule.
CONCLUSIONS
The femoral and obturator nerves and the nerve to the quadratus femoris were found to consistently supply articular branches to both the anterior and posterior capsule of the hip joint. The anterior capsule, primarily supplied by the femoral and obturator nerves, and the superior labrum appear to be the primary pain generators of the hip joint, given their higher density of nociceptors and mechanoreceptors.
LEVEL OF EVIDENCE
Anatomy study, literature review.
Topics: Hip Joint; Humans; Joint Capsule; Obturator Nerve; Pain
PubMed: 33565587
DOI: 10.1093/pm/pnab061 -
Journal of Sport and Health Science Mar 2021Acute ankle injury causes damage to joint mechanoreceptors and deafferentation and contributes to proprioception deficits in patients with chronic ankle instability... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Acute ankle injury causes damage to joint mechanoreceptors and deafferentation and contributes to proprioception deficits in patients with chronic ankle instability (CAI). We aimed to explore whether deficits of proprioception, including kinesthesia and joint position sense (JPS), exist in patients with CAI when compared with the uninjured contralateral side and healthy people. We hypothesized that proprioception deficits did exist in patients with CAI and that the deficits varied by test methodologies.
METHODS
The study was a systematic review and meta-analysis. We identified studies that compared kinesthesia or JPS in patients with CAI with the uninjured contralateral side or with healthy controls. Meta-analyses were conducted for the studies with similar test procedures, and narrative syntheses were undertaken for the rest.
RESULTS
A total of 7731 studies were identified, of which 30 were included for review. A total of 21 studies were eligible for meta-analysis. Compared with the contralateral side, patients with CAI had ankle kinesthesia deficits in inversion and plantarflexion, with a standardized mean difference (SMD) of 0.41 and 0.92, respectively, and active and passive JPS deficits in inversion (SMD = 0.92 and 0.72, respectively). Compared with healthy people, patients with CAI had ankle kinesthesia deficits in inversion and eversion (SMD = 0.64 and 0.76, respectively), and active JPS deficits in inversion and eversion (SMD = 1.00 and 4.82, respectively). Proprioception deficits in the knee and shoulder of patients with CAI were not statistically significant.
CONCLUSION
Proprioception, including both kinesthesia and JPS, of the injured ankle of patients with CAI was impaired, compared with the uninjured contralateral limbs and healthy people. Proprioception varied depending on different movement directions and test methodologies. The use of more detailed measurements of proprioception and interventions for restoring the deficits are recommended in the clinical management of CAI.
Topics: Ankle Injuries; Ankle Joint; Bias; Chronic Disease; Humans; Joint Instability; Kinesthesis; Knee Joint; Movement; Proprioception; Sensation Disorders; Shoulder Joint
PubMed: 33017672
DOI: 10.1016/j.jshs.2020.09.014 -
Advanced Drug Delivery Reviews Jan 2020The process of aging influences every bodily organ and tissue, and those with rapid epithelial cell turnover, are particularly affected. The most visible of these,...
The process of aging influences every bodily organ and tissue, and those with rapid epithelial cell turnover, are particularly affected. The most visible of these, however, is the skin (including the epidermis), the largest human organ that provides a barrier to external insults, structure to the body and its movements, facilitates thermoregulation, harbors immune cells, and incorporates sensory neurons (including mechanoreceptors, nociceptors, and thermoreceptors). Skin aging has traditionally been categorized into intrinsic and extrinsic, with the latter nearly exclusively restricted to "photoaging," (i.e., aging due to exposure to solar or artificial ultraviolet radiation). However, both intrinsic and extrinsic aging share similar causes, including oxidative damage, telomere shortening, and mitochondrial senescence. Also, like other malignancies, the risk of malignant and nonmalignant lesions increases with age. Herein, we review the most recent findings in skin aging and nonmelanoma skin cancer, including addition to traditional and developing therapies.
Topics: Administration, Cutaneous; Aging; Antineoplastic Agents; Cosmetic Techniques; Dermatologic Agents; Drug Delivery Systems; Epigenesis, Genetic; Humans; Skin; Skin Aging; Skin Neoplasms; Ultraviolet Rays
PubMed: 32526451
DOI: 10.1016/j.addr.2020.06.004 -
PloS One 2020The hip joint capsule contributes to the stability of the hip joint and lower extremity, yet this structure is incised and often removed during total hip arthroplasty...
Innervation of the hip joint capsular complex: A systematic review of histological and immunohistochemical studies and their clinical implications for contemporary treatment strategies in total hip arthroplasty.
The hip joint capsule contributes to the stability of the hip joint and lower extremity, yet this structure is incised and often removed during total hip arthroplasty (THA). Increasing incidence of osteoarthritis is accompanied by a dramatic rise in THAs over the last few decades. Consequently, to improve this treatment, THA with capsular repair has evolved. This partial restoration of physiological hip stability has resulted in a substantial reduction in post-operative dislocation rates compared to conventional THA without capsular repair. A further reason for the success of this procedure is thought to be the preservation of the innervation of the capsule. A systematic review of studies investigating the innervation of the hip joint capsular complex and pseudocapsule with histological techniques was performed, as this is not well established. The literature was sought from databases Amed, Embase and Medline via OVID, PubMed, ScienceDirect, Scopus and Web of Science; excluding articles without a histological component and those involving animals. A total of 21 articles on the topic were identified. The literature indicates two primary outcomes and potential clinical implications of the innervation of the capsule. Firstly, a role in the mechanics of the hip joint, as mechanoreceptors may be present in the capsule. However, the nomenclature used to describe the distribution of the innervation is inconsistent. Furthermore, the current literature is unable to reliably confirm the proprioceptive role of the capsule, as no immunohistochemical study to date has reported type I-III mechanoreceptors in the capsule. Secondly, the capsule may play a role in pain perception, as the density of innervation appears to be altered in painful individuals. Also, increasing age may indicate requirements for different strategies to surgically manage the hip capsule. However, this requires further study, as well as the role of innervation according to sex, specific pathology and other morphometric variables. Increased understanding may highlight the requirement for capsular repair following THA, how this technique may be developed and the contribution of the capsule to joint function and stability.
Topics: Arthroplasty, Replacement, Hip; Hip Joint; Humans; Joint Capsule; Joint Instability; Postoperative Complications
PubMed: 32101545
DOI: 10.1371/journal.pone.0229128 -
The Journal of Hand Surgery, European... Nov 2019Tumours involving Pacinian corpuscles are rare. The literature identifies two main pathological disorders: the Pacinian corpuscle neuroma or hyperplasia and the Pacinian...
Tumours involving Pacinian corpuscles are rare. The literature identifies two main pathological disorders: the Pacinian corpuscle neuroma or hyperplasia and the Pacinian corpuscle neurofibroma. Published data are confusing and at times conflicting. This systematic review summarizes the available data in order to support clinicians in the differential diagnosis with other tumours responsible for unclear symptoms in the hands and fingers. We identified 67 pertinent articles. Although some similarities have been described, the two tumours have relevant differences, specifically when comparing age of the patient, location, symptoms, characteristic of a mass, and aetiology. All these factors should be taken into account in order to improve diagnostic accuracy. Despite the low incidence of unsuccessful surgeries, extraordinary measures are occasionally necessary to achieve complete resolution of symptoms.
Topics: Diagnosis, Differential; Hand; Humans; Hyperplasia; Neurofibroma; Neuroma; Pacinian Corpuscles
PubMed: 31156019
DOI: 10.1177/1753193419852118 -
Gait & Posture Jun 2019Standing on textured materials can improve static balance, potentially by modulating somatosensory inputs from the soles of the feet. (Meta-Analysis)
Meta-Analysis
BACKGROUND
Standing on textured materials can improve static balance, potentially by modulating somatosensory inputs from the soles of the feet.
RESEARCH QUESTION
To synthesise and quantify the immediate effects of textured materials on static balance in healthy young and older adults.
METHODS
Primary outcomes were the centre of pressure (COP) displacement and velocity, during eyes open and eyes closed conditions. Ten crossover studies (n = 318, 58% female) met the inclusion criteria. A random effects meta-analysis model derived pooled standardised mean differences (SMD; Hedges g) to quantify the effects of textured materials. Heterogeneity was quantified with the tau-statistic (τ). A 95% prediction interval quantified the likely range of true effects on COP outcomes in similar future studies.
RESULTS
There was a small to moderate beneficial effect for textured materials vs control conditions in: COP displacement during both eyes open (SMD: 0.29; 95% CI -0.06 to 0.64; τ = 0.32) and eyes closed (SMD: 0.75; 95% CI 0.18 to 1.33; τ = 0.55). A trivial to small beneficial effect was observed in COP velocity during eyes open (SMD: 0.14; 95% CI -0.14 to 0.43; τ = 0.18) and eyes closed (SMD: 0.20; 95% CI 0.01 to 0.40; τ = 0.18) for textured materials. The 95% prediction intervals showed texture may not consistently provide beneficial results across studies for all outcomes: COP displacement EC (-0.61 to 2.12), EO (-0.54 to 1.12), COP velocity EC (-0.27 to 0.68) and EO (-0.44 to 0.73).
SIGNIFICANCE
Overall, textured materials improved balance, but these effects were heterogeneous. This research may therefore inform applied investigations into balance improvements for healthy populations, for example, in functional movements and sports.
Topics: Aged; Cross-Over Studies; Female; Foot; Gait; Humans; Male; Movement; Orthotic Devices; Postural Balance; Pressure; Sports
PubMed: 31022658
DOI: 10.1016/j.gaitpost.2019.04.017