Background: Systemic dehydration negatively alters the expression of vocal fold inflammatory and cell junction markers. These biological changes can have downstream effects on the healing processes of injured vocal folds. In the dermis, reduced hydration prolongs inflammation and delays healing. A similar finding in vocal fold tissue would have significant clinical impact.
Objective: To investigate the effects of systemic dehydration on cellular vocal fold healing outcomes following acute vocal fold injury.
Methods: Male Sprague Dawley rats (4-5 months) were systemically dehydrated (N = 9) or euhydrated (N = 9). All rats underwent vocal fold injury and were euthanized 24-hours post-injury. Eighteen age-matched rats served as non-injured controls and were euthanized at 24 hours. Outcome measures: Following histopathological characterization of the vocal injury, gene expression levels of inflammatory (IL-1β; TNF-α, TGF-β) and epithelial cell junction markers (Cadherin-3, Desmoglein-1) were obtained. Protein validation analysis using Western Blotting is currently underway.
Results: Extravasated erythrocytes and neutrophils are observed within the vocal fold lamina propria 24-hours post-injury. At this timepoint, pro-inflammatory gene markers (IL-1β; TNF-α), are differentially expressed in response to systemic dehydration. Epithelial cell junction markers (Cadherin-3, Desmoglein-1) exhibit divergent trends in injured and control vocal fold tissue following dehydration. These findings are currently being validated with protein expression analysis.
Conclusions: These data suggest that systemic dehydration alters cellular vocal fold healing processes immediately following injury. Continued investigations will focus on whether the restoration of hydration can mitigate these adverse effects.