Premium
Raised intensity phonation compromises vocal fold epithelial barrier integrity
Author(s) -
Rousseau Bernard,
Suehiro Atsushi,
Echemendia Nicholas,
Sivasankar Mahalakshmi
Publication year - 2011
Publication title -
the laryngoscope
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.181
H-Index - 148
eISSN - 1531-4995
pISSN - 0023-852X
DOI - 10.1002/lary.21364
Subject(s) - phonation , adherens junction , occludin , tight junction , biology , desquamation , intracellular , vocal folds , cell junction , epithelium , microbiology and biotechnology , cadherin , gap junction , pathology , anatomy , medicine , audiology , genetics , larynx , cell
Objectives/Hypothesis: We investigated the hypothesis that 30 minutes of raised intensity phonation alters transcript levels of vocal fold intercellular tight junction proteins and disrupts the vocal fold epithelial barrier. Study Design: Prospective animal study. Methods: Eighteen New Zealand white breeder rabbits were randomly assigned to receive 30 minutes of raised intensity phonation or approximation of the vocal folds without phonation. Quantitative polymerase chain reaction (qPCR) was used to investigate transcript levels of the epithelial intercellular tight junction proteins, occludin and zonula occludin‐1 (ZO‐1), and the adherens junction proteins β‐catenin and E‐cadherin. Structural alterations to the vocal fold epithelium were further examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results: Mann‐Whitney U revealed significantly decreased occludin ( P = .016) and β‐catenin ( P = .016) gene expression from rabbits undergoing raised intensity phonation compared with control. There were no significant differences in Z0‐1 and E‐cadherin gene expression between groups ( P > .025 ). SEM revealed significant obliteration, desquamation, and evidence of microhole formation in rabbit vocal folds exposed to raised intensity phonation compared with control, whereas TEM revealed dilated intercellular morphology between groups. Conclusions: Results provide support for the hypothesis that a transient episode of raised intensity phonation alters transcript levels of vocal fold intercellular tight junction proteins and disrupts integrity of the epithelial barrier. The loss of barrier integrity may have significant consequences on epithelial defenses and compromise protection of the underlying mucosa from damage secondary to prolonged vibration exposure.