Background: Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by social communication challenges and repetitive behaviors. Recent research has increasingly focused on the genetic underpinnings of ASD, with the Neurexin 1 (NRXN1) gene emerging as a key player. This comprehensive systematic review elucidates the contribution of NRXN1 gene variants in the pathophysiology of ASD. Methods: The protocol for this systematic review was designed a priori and was registered in the PROSPERO database (CRD42023450418). A risk of bias analysis was conducted using the Joanna Briggs Institute (JBI) critical appraisal tool. We examined various studies that link NRXN1 gene disruptions with ASD, discussing both the genotypic variability and the resulting phenotypic expressions. Results: Within this review, there was marked heterogeneity observed in ASD genotypic and phenotypic manifestations among individuals with NRXN1 mutations. The presence of NRXN1 mutations in this population emphasizes the gene’s role in synaptic function and neural connectivity. Conclusion: This review not only highlights the role of NRXN1 in the pathophysiology of ASD but also highlights the need for further research to unravel the complex genetic underpinnings of the disorder. A better knowledge about the multifaceted role of NRXN1 in ASD can provide crucial insights into the neurobiological foundations of autism and pave the way for novel therapeutic strategies.
Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by stereotyped and repetitive behavior patterns. In addition to neurological and behavioral problems, individuals with ASD commonly experience otolaryngological comorbidities. Individuals with ASD often have auditory disorders including hearing loss and auditory processing disorders such as central auditory processing disorder (CAPD), as well as both chronic and recurrent otitis media. These challenges negatively impact a person’s ability to effectively communicate and may further impact their neurological functioning, particularly when not appropriately treated. Individuals diagnosed with ASD also have difficulty sleeping which contributes to increased irritability and may further aggravate the core behavioral symptoms of autism. The individuals with ASD also have a higher rate of sinusitis which contributes to the worsening of the autism behavior phenotype. The high prevalence of otolaryngological comorbidities in individuals with ASD warrants a better collaboration between their various healthcare providers and otolaryngologists with expertise in auditory, sleep, and sinus disorders in pursuit of improving the quality of life of affected individuals and their families/caregivers.
Background: Autism spectrum disorder (ASD) is a complex neurodevelopmental condition with a rising prevalence, driven by multifactorial genetic and environmental factors. Among the genetic contributors identified, SCN2A, a critical gene encoding the Nav1.2 sodium channel, has been implicated in ASD and other related neurological conditions. This systematic review aims to explore the relationship between SCN2A mutations and ASD phenotypes. Methods: This review systematically analyzed data from studies reporting SCN2A mutations in individuals diagnosed with ASD. The primary focus was on the characterization of mutation types, associated clinical features, and phenotypic variability. Results: The mutations identified were predominantly de novo missense mutations and were associated with a spectrum of neurological and developmental challenges, including seizures, intellectual disability, movement disorders, and repetitive behaviors. A notable finding was the significant phenotypic variability observed across individuals. Gender differences emerged, suggesting a potentially greater impact on females compared to trends typically seen in ASD genetic studies. Specific mutations, such as c.2919+4delT, and mosaicism were identified as novel contributors to the observed heterogeneity. Conclusions: The review highlights the clinical significance of SCN2A mutations in ASD and highlights their relevance in genetic counseling and the development of targeted therapies. Understanding the diverse genotype–phenotype correlations associated with SCN2A can drive progress in personalized medicine, paving the way for precision therapies tailored to individuals with SCN2A-related ASD.
Background: Vestibular schwannoma (VS) is a benign tumor of the eighth cranial nerve formed from neoplastic Schwann cells. Although VS can cause a variety of symptoms, tinnitus is one of the most distressing symptoms for patients and can greatly impact quality of life. The objective of this systematic review is to comprehensively examine and compare the outcomes related to tinnitus in patients undergoing treatment for VS. Specifically, it evaluates patient experiences with tinnitus following the removal of VS using the various surgical approaches of traditional surgical resection and gamma knife radiosurgery (GKS). By delving into various aspects such as the severity of tinnitus post-treatment, the duration of symptom relief, patient quality of life, new onset of tinnitus after VS treatment, and any potential complications or side effects, this review aims to provide a detailed analysis of VS treatment on tinnitus outcomes. Methods: Following PRISMA guidelines, articles were included from PubMed, Science Direct, Scopus, and EMBASE. Quality assessment and risk of bias analysis were performed using a ROBINS-I tool. Results: Although VS-associated tinnitus is variable in its intensity and persistence post-resection, there was a trend towards a decreased tinnitus burden in patients. Irrespective of the surgical approach or the treatment with GKS, there were cases of persistent or worsened tinnitus within the studied cohorts. Conclusion: The findings of this systematic review highlight the complex relationship between VS resection and tinnitus outcomes. These findings underscore the need for individualized patient counseling and tailored treatment approaches in managing VS-associated tinnitus. The findings of this systematic review may help in guiding clinicians towards making more informed and personalized healthcare decisions. Further studies must be completed to fill gaps in the current literature.
Background: Cochlear implantation is widely used to provide auditory rehabilitation to individuals with severe-to-profound sensorineural hearing loss. However, electrode insertion during cochlear implantation leads to inner ear trauma, damage to sensory structures, and consequently, loss of residual hearing. There is very limited information regarding the target proteins involved in electrode insertion trauma (EIT) following cochlear implantation. Methods: The aim of our study was to identify target proteins and host molecular pathways involved in cochlear damage following EIT utilizing the iTRAQ™ (isobaric tags for relative and absolute quantification) technique using our ex vivo model. The organ of Corti (OC) explants were dissected from postnatal day 3 rats and subjected to EIT or left untreated (control). The proteins were extracted, labelled, and subjected to ultra-high performance liquid chromatography–tandem mass spectrometry. Results: We identified distinct molecular pathways involved in EIT-induced cochlear damage. Confocal microscopy confirmed the expression of these identified proteins in OC explants subjected to EIT. By separating the apical, middle, and basal cochlear turns, we deciphered a topographic array of host molecular pathways that extend from the base to the apex of the cochlea, which are activated post-trauma following cochlear implantation. Conclusions: The identification of target proteins involved in cochlear damage will provide novel therapeutic targets for the development of effective treatment modalities for the preservation of residual hearing in implanted individuals.