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Frontiers in Cellular Neuroscience 2024Efferent feedback to the mammalian cochlea includes cholinergic medial olivocochlear neurons (MOCs) that release ACh to hyperpolarize and shunt the voltage change that... (Review)
Review
Efferent feedback to the mammalian cochlea includes cholinergic medial olivocochlear neurons (MOCs) that release ACh to hyperpolarize and shunt the voltage change that drives electromotility of outer hair cells (OHCs). Via brainstem connectivity, MOCs are activated by sound in a frequency- and intensity-dependent manner, thereby reducing the amplification of cochlear vibration provided by OHC electromotility. Among other roles, this efferent feedback protects the cochlea from acoustic trauma. Lesion studies, as well as a variety of genetic mouse models, support the hypothesis of efferent protection from acoustic trauma. Genetic knockout and gain-of-function knockin of the unique α9α10-containing nicotinic acetylcholine receptor (nAChR) in hair cells show that acoustic protection correlates with the efficacy of cholinergic inhibition of OHCs. This protective effect was replicated by viral transduction of the gain-of-function α9L9'T nAChR into α9-knockout mice. Continued progress with "efferent gene therapy" will require a reliable method for visualizing nAChR expression in cochlear hair cells. To that end, mice expressing HA-tagged α9 or α10 nAChRs were generated using CRISPR technology. This progress will facilitate continued study of the hair cell nAChR as a therapeutic target to prevent hearing loss and potentially to ameliorate associated pathologies such as hyperacusis.
PubMed: 38560293
DOI: 10.3389/fncel.2024.1372948 -
Headache Sep 2023To examine whether sensory hypersensitivity contributes to headache-related disability in a secondary analysis of patients with post-traumatic headache.
OBJECTIVE
To examine whether sensory hypersensitivity contributes to headache-related disability in a secondary analysis of patients with post-traumatic headache.
BACKGROUND
Up to one-third of individuals with traumatic brain injuries report persistent headache 3 months post-injury. High rates of allodynia and photophobia have been observed in clinical studies and animal models of post-traumatic headache, but we do not fully understand how sensory amplifications impact post-traumatic headache-related disability.
METHODS
We identified a cross-sectional sample of patients from the American Registry for Migraine Research database with new or worsening headaches post-head injury from 2016 to 2020 and performed a secondary analysis of those data. We modeled the relationship between sensory sensitivity and Migraine Disability Assessment scores using questionnaires. Candidate variables included data collection features (study site and year), headache-related and general clinical features (headache frequency, migraine diagnosis, abuse history, sex, age, cognitive and affective symptom scores), and sensory symptoms (related to light, sound, and touch sensitivity).
RESULTS
The final sample included 193 patients (median age 46, IQR 22; 161/193, 83.4% female). Migraine Disability Assessment scores ranged from 0 to 260 (median 47, IQR 87). The final model included allodynia, hyperacusis, photosensitivity, headache days per month, abuse history, anxiety and depression, cognitive dysfunction, and age (R = 0.43). An increase of one point in allodynia score corresponded to a 3% increase in headache disability (95% CI: 0%-7%; p = 0.027), an increase of one-tenth of a point in the photosensitivity score corresponded to a 12% increase (95% CI: 3%-25%; p = 0.002), and an increase of one point in the hyperacusis score corresponded to a 2% increase (95% CI: 0%-4%; p = 0.016).
CONCLUSIONS
Increased photosensitivity, allodynia, and hyperacusis were associated with increased headache-related disability in this sample of patients with post-traumatic headache. Symptoms of sensory amplification likely contribute to post-traumatic headache-related disability and merit an ongoing investigation into their potential as disease markers and treatment targets.
Topics: Female; Animals; Male; Post-Traumatic Headache; Cross-Sectional Studies; Hyperacusis; Hyperalgesia; Headache; Migraine Disorders; Hypersensitivity
PubMed: 37638410
DOI: 10.1111/head.14604 -
Trends in Hearing 2024Cochlear synaptopathy, a form of cochlear deafferentation, has been demonstrated in a number of animal species, including non-human primates. Both age and noise exposure... (Review)
Review
Cochlear synaptopathy, a form of cochlear deafferentation, has been demonstrated in a number of animal species, including non-human primates. Both age and noise exposure contribute to synaptopathy in animal models, indicating that it may be a common type of auditory dysfunction in humans. Temporal bone and auditory physiological data suggest that age and occupational/military noise exposure also lead to synaptopathy in humans. The predicted perceptual consequences of synaptopathy include tinnitus, hyperacusis, and difficulty with speech-in-noise perception. However, confirming the perceptual impacts of this form of cochlear deafferentation presents a particular challenge because synaptopathy can only be confirmed through post-mortem temporal bone analysis and auditory perception is difficult to evaluate in animals. Animal data suggest that deafferentation leads to increased central gain, signs of tinnitus and abnormal loudness perception, and deficits in temporal processing and signal-in-noise detection. If equivalent changes occur in humans following deafferentation, this would be expected to increase the likelihood of developing tinnitus, hyperacusis, and difficulty with speech-in-noise perception. Physiological data from humans is consistent with the hypothesis that deafferentation is associated with increased central gain and a greater likelihood of tinnitus perception, while human data on the relationship between deafferentation and hyperacusis is extremely limited. Many human studies have investigated the relationship between physiological correlates of deafferentation and difficulty with speech-in-noise perception, with mixed findings. A non-linear relationship between deafferentation and speech perception may have contributed to the mixed results. When differences in sample characteristics and study measurements are considered, the findings may be more consistent.
Topics: Humans; Cochlea; Tinnitus; Animals; Speech Perception; Hyperacusis; Noise; Auditory Perception; Synapses; Hearing Loss, Noise-Induced; Loudness Perception
PubMed: 38738337
DOI: 10.1177/23312165241239541 -
The Journal of Headache and Pain Aug 2023It is unknown whether new daily persistent headache (NDPH) is a single disorder or heterogenous group of disorders, and whether it is a unique disorder from chronic...
BACKGROUND
It is unknown whether new daily persistent headache (NDPH) is a single disorder or heterogenous group of disorders, and whether it is a unique disorder from chronic migraine and chronic tension-type headache. We describe a large group of patients with primary NDPH, compare its phenotype to transformed chronic daily headache (T-CDH), and use cluster analysis to reveal potential sub-phenotypes in the NDPH group.
METHODS
We performed a case-control study using prospectively collected clinical data in patients with primary NDPH and T-CDH (encompassing chronic migraine and chronic tension-type headache). We used logistic regression with propensity score matching to compare demographics, phenotype, comorbidities, and treatment responses between NDPH and T-CDH. We used K-means cluster analysis with Gower distance to identify sub-clusters in the NDPH group based on a combination of demographics, phenotype, and comorbidities.
RESULTS
We identified 366 patients with NDPH and 696 with T-CDH who met inclusion criteria. Patients with NDPH were less likely to be female (62.6% vs. 73.3%, p < 0.001). Nausea, vomiting, photophobia, phonophobia, motion sensitivity, vertigo, and cranial autonomic symptoms were all significantly less frequent in NDPH than T-CDH (p value for all < 0.001). Acute treatments appeared less effective in NDPH than T-CDH, and medication overuse was less common (16% vs. 42%, p < 0.001). Response to most classes of oral preventive treatments was poor in both groups. The most effective treatment in NDPH was doselupin in 45.7% patients (95% CI 34.8-56.5%). Cluster analysis identified three subgroups of NDPH. Cluster 1 was older, had a high proportion of male patients, and less severe headaches. Cluster 2 was predominantly female, had severe headaches, and few associated symptoms. Cluster 3 was predominantly female with a high prevalence of migrainous symptoms and headache triggers.
CONCLUSIONS
Whilst there is overlap in the phenotype of NDPH and T-CDH, the differences in migrainous, cranial autonomic symptoms, and vulnerability to medication overuse suggest that they are not the same disorder. NDPH may be fractionated into three sub-phenotypes, which require further investigation.
Topics: Female; Male; Humans; Tension-Type Headache; Case-Control Studies; Headache Disorders; Headache; Migraine Disorders; Phenotype
PubMed: 37587430
DOI: 10.1186/s10194-023-01639-5 -
Journal of the Association For Research... Feb 2024To assess the available evidence to support a genetic contribution and define the role of common and rare variants in tinnitus.
PURPOSE
To assess the available evidence to support a genetic contribution and define the role of common and rare variants in tinnitus.
METHODS
After a systematic search and quality assessment, 31 records including 383,063 patients were selected (14 epidemiological studies and 17 genetic association studies). General information on the sample size, age, sex, tinnitus prevalence, severe tinnitus distribution, and sensorineural hearing loss was retrieved. Studies that did not include data on hearing assessment were excluded. Relative frequencies were used for qualitative variables to compare different studies and to obtain average values. Genetic variants and genes were listed and clustered according to their potential role in tinnitus development.
RESULTS
The average prevalence of tinnitus estimated from population-based studies was 26.3% for any tinnitus, and 20% of patients with tinnitus reported it as an annoying symptom. One study has reported population-specific differences in the prevalence of tinnitus, the white ancestry being the population with a higher prevalence. Genome-wide association studies have identified and replicated two common variants in the Chinese population (rs2846071; rs4149577) in the intron of TNFRSF1A, associated with noise-induced tinnitus. Moreover, gene burden analyses in sequencing data from Spanish and Swede patients with severe tinnitus have identified and replicated ANK2, AKAP9, and TSC2 genes.
CONCLUSIONS
The genetic contribution to tinnitus is starting to be revealed and it shows population-specific effects in European and Asian populations. The common allelic variants associated with tinnitus that showed replication are associated with noise-induced tinnitus. Although severe tinnitus has been associated with rare variants with large effect, their role on hearing or hyperacusis has not been established.
Topics: Humans; Tinnitus; Genome-Wide Association Study; Hearing; Hearing Loss, Sensorineural; Hyperacusis
PubMed: 38334885
DOI: 10.1007/s10162-024-00925-6 -
PloS One 2023Recently, the most bothersome symptom has been recommended as a co-primary endpoint in clinical trials on the acute treatment of migraine. Probable migraine is a subtype...
Recently, the most bothersome symptom has been recommended as a co-primary endpoint in clinical trials on the acute treatment of migraine. Probable migraine is a subtype of migraine that fulfills all but one criterion for migraine diagnosis. We aimed to compare the most bothersome symptom between probable migraine and migraine. This study analyzed data from a nationwide study conducted in Korea, and the most bothersome symptom was assessed by requesting the participants to select one of the four typical accompanying symptoms of migraine. Responses to acute treatment were evaluated using the migraine Treatment Optimization Questionnaire-6. Nausea was the most bothersome symptom, followed by phonophobia and vomiting in the migraine group (nausea, 61.8%; phonophobia, 25.3%; vomiting, 10.0%; and photophobia, 2.9%) and the probable migraine group (nausea, 82.2%; phonophobia, 9.5%; vomiting, 5.6%; and photophobia, 2.7%). In participants with migraine, vomiting (adjusted odds ratio = 6.513; 95% confidence interval, 1.763-24.057) and phonophobia (adjusted odds ratio = 0.437; 95% confidence interval, 0.206-0.929) were significantly associated with severe headache intensity and nausea was significantly associated with >3 headache days per 30 days (adjusted odds ratio = 0.441; 95% confidence, 0.210-0.927). Different patterns of associations were observed in probable migraine.
Topics: Humans; Photophobia; Hyperacusis; Migraine Disorders; Nausea; Vomiting; Headache; Surveys and Questionnaires; Double-Blind Method
PubMed: 38019845
DOI: 10.1371/journal.pone.0289729 -
Ideggyogyaszati Szemle Sep 2023
Migraine as a common primary headache disorder has a significant negative effect on quality of life of the patients. Its pharmacotreatment includes acute and... (Review)
Review
Migraine as a common primary headache disorder has a significant negative effect on quality of life of the patients. Its pharmacotreatment includes acute and preventative therapies. Based on the shared therapeutic guideline of the European Headache Federation and the European Academy of Neurology for acute migraine treatment a combination of triptans and non-steroidal anti-inflammatory drugs is recommended for acute migraine treatment in triptan-nonresponders. In this short review we summarized the results of the randomized controlled clinical trials evaluating the effectiveness and safety of sumatriptan (85 mg)/naproxen sodium (500 mg) fix-dose combination. It was revealed that the fix-dose combination was better than placebo for the primary outcomes of exemption of pain and headache relief at 2 hours. Furthermore the combination showed beneficial effect on accompanying symptoms of migraine attack (i.e. nausea, photo- and phonophobia). Adverse events were mild or moderate in severity and rarely led to withdrawal of the drug.
.
It can be concluded that sumatriptan (85 mg)/naproxen sodium (500 mg) fix-dose combination is effective, safe and well-tolerated in the acute treatment of migraine.Topics: Humans; Double-Blind Method; Drug Therapy, Combination; Headache; Migraine Disorders; Naproxen; Quality of Life; Sodium; Sumatriptan; Tryptamines
PubMed: 37782065
DOI: 10.18071/isz.76.0293 -
Journal of the Association For Research... Dec 2023Tinnitus would benefit from an objective biomarker. The goal of this study is to identify plasma biomarkers of constant and chronic tinnitus among selected circulating... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND OBJECTIVE
Tinnitus would benefit from an objective biomarker. The goal of this study is to identify plasma biomarkers of constant and chronic tinnitus among selected circulating inflammatory proteins.
METHODS
A case-control retrospective study on 548 cases with constant tinnitus and 548 matched controls from the Swedish Tinnitus Outreach Project (STOP), whose plasma samples were examined using Olink's Inflammatory panel. Replication and meta-analysis were performed using the same method on samples from the TwinsUK cohort. Participants from LifeGene, whose blood was collected in Stockholm and Umeå, were recruited to STOP for a tinnitus subtyping study. An age and sex matching was performed at the individual level. TwinsUK participants (n = 928) were selected based on self-reported tinnitus status over 2 to 10 years. Primary outcomes include normalized levels for 96 circulating proteins, which were used as an index test. No reference standard was available in this study.
RESULTS
After adjustment for age, sex, BMI, smoking, hearing loss, and laboratory site, the top proteins identified were FGF-21, MCP4, GDNF, CXCL9, and MCP-1; however, these were no longer statistically significant after correction for multiple testing. Stratification by sex did not yield any significant associations. Similarly, associations with hearing loss or other tinnitus-related comorbidities such as stress, anxiety, depression, hyperacusis, temporomandibular joint disorders, and headache did not yield any significant associations. Analysis in the TwinsUK failed in replicating the top candidates. Meta-analysis of STOP and TwinsUK did not reveal any significant association. Using elastic net regularization, models exhibited poor predictive capacity tinnitus based on inflammatory markers [sensitivity = 0.52 (95% CI 0.47-0.57), specificity = 0.53 (0.48-0.58), positive predictive value = 0.52 (0.47-0.56), negative predictive values = 0.53 (0.49-0.58), and AUC = 0.53 (0.49-0.56)].
DISCUSSION
Our results did not identify significant associations of the selected inflammatory proteins with constant tinnitus. Future studies examining longitudinal relations among those with more severe tinnitus and using more recent expanded proteomics platforms and sampling of cerebrospinal fluid could increase the likelihood of identifying relevant molecular biomarkers.
Topics: Humans; Tinnitus; Retrospective Studies; Hearing Loss; Hyperacusis; Biomarkers
PubMed: 38079022
DOI: 10.1007/s10162-023-00920-3 -
Infection Jun 2024To describe clinical features and outcomes of viral lumbosacral radiculitis (Elsberg syndrome).
PURPOSE
To describe clinical features and outcomes of viral lumbosacral radiculitis (Elsberg syndrome).
METHODS
Nationwide population-based cohort study of all adults hospitalised for viral lumbosacral radiculitis at departments of infectious diseases in Denmark from 2015 to 2020.
RESULTS
Twenty-eight patients with viral lumbosacral radiculitis were included (mean annual incidence: 1.2/1,000,000 adults). The median age was 35 years (IQR 27-43), and 22/28 (79%) were female. All patients had urinary retention, with 17/28 (61%) needing a catheter. On admission, at least one sign or symptom of meningitis (headache, neck stiffness, photophobia/hyperacusis) was present in 18/22 (82%). Concurrent genital herpetic lesions were present in 11/24 (46%). The median cerebrospinal fluid leukocyte count was 153 cells/µL (IQR 31-514). Magnetic resonance imaging showed radiculitis/myelitis in 5/19 (26%). The microbiological diagnosis was herpes simplex virus type 2 in 19/28 (68%), varicella-zoster virus in 2/28 (7%), and unidentified in 7/28 (25%). Aciclovir/valaciclovir was administered in 27/28 (96%). At 30 days after discharge, 3/27 (11%) had persistent urinary retention with need of catheter. At 180 days after discharge, moderate disabilities (Glasgow Outcome Scale score of 4) were observed in 5/25 (20%).
CONCLUSIONS
Urinary retention resolved within weeks in most patients with viral lumbosacral radiculitis, but moderate disabilities according to the Glasgow Outcome Scale were common at the end of follow-up.
Topics: Humans; Denmark; Female; Adult; Male; Radiculopathy; Cohort Studies; Urinary Retention; Herpesvirus 2, Human; Middle Aged; Lumbosacral Region; Herpes Zoster; Herpesvirus 3, Human
PubMed: 37917395
DOI: 10.1007/s15010-023-02113-9