Effects of phonation time and magnitude dose on vocal fold epithelial genes, barrier integrity, and function. (30th July 2014)

• Record Type: Journal Article
• Authors: Kojima, Tsuyoshi; Valenzuela, Carla V.; Novaleski, Carolyn K.; Van Deusen, Mark; Mitchell, Joshua R.; Garrett, C. Gaelyn; Sivasankar, M. Preeti; Rousseau, Bernard
• Is Part Of: Laryngoscope. Volume 124:Number 12(2014:Dec.)
• Page Start: 2770
• Page End: 2778
• Publication Date: 2014-07-30
• Subjects: Otolaryngology -- Periodicals; 617.51005
• DOI: 10.1002/lary.24827
• Languages: English
• ISSNs: 0023-852X

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="lary24827-sec-0001" sec-type="section"> <title>Objectives/Hypothesis</title> <p>To investigate the effects of increasing time and magnitude doses of vibration exposure on transcription of the vocal fold's junctional proteins, structural alterations, and functional tissue outcomes.</p> </sec> <sec id="lary24827-sec-0002" sec-type="section"> <title>Study Design</title> <p>Animal study.</p> </sec> <sec id="lary24827-sec-0003" sec-type="section"> <title>Methods</title> <p>100 New Zealand White breeder rabbits were studied. Dependent variables were measured in response to increasing time doses (30, 60, or 120 minutes) and magnitude doses (control, modal intensity, and raised intensity) of vibration exposure. Messenger RNA expression of occludin, zonula occluden‐1 (ZO‐1), E‐cadherin, β‐catenin, interleukin 1β, cyclooxygenase‐2, transforming growth factor β‐1, and fibronectin were measured. Tissue structural alterations were assessed using transmission electron microscopy (TEM). Transepithelial resistance was used to measure functional tissue outcomes.</p> </sec> <sec id="lary24827-sec-0004" sec-type="section"> <title>Results</title> <p>Occludin gene expression was downregulated in vocal folds exposed to 120‐minute time doses of raised‐intensity phonation, relative to control, and modal‐intensity phonation. ZO‐1 gene expression was upregulated following a 120‐minute time dose of modal‐intensity phonation, compared to control, and downregulated after a 120‐minute time dose of raised‐intensity phonation, compared to modal‐intensity phonation. E‐cadherin gene expression was downregulated after a 120‐minute time dose of raised‐intensity phonation, compared to control and modal‐intensity phonation. TEM revealed extensive desquamation of the stratified squamous epithelial cells with increasing time and magnitude doses of vibration exposure. A general observation of lower transepithelial resistance measures was made in tissues exposed to raised‐intensity phonation compared to all other groups.</p> </sec> <sec id="lary24827-sec-0005" sec-type="section"> <title>Conclusions</title> <p>This study provides evidence of vocal fold tissue responses to varying time and magnitude doses of vibration exposure.</p> </sec> <sec id="lary24827-sec-0006" sec-type="section"> <title>Level of Evidence</title> <p>NA <italic>Laryngoscope</italic>, 124:2770–2778, 2014</p> </sec> </abstract>