Effect of astaxanthin on vocal fold wound healing

Our previous study demonstrated that a large amount of reactive oxygen species (ROS) is produced during the early phase of vocal fold wound healing. In the current study, we investigated the effect of astaxanthin, which is a strong antioxidant, on the regulation of oxidative stress and scarring during vocal fold wound healing.

Prospective animal experiment with control.

Sprague-Dawley rats were dosed with astaxanthin (Ast-treated group, 100 mg/kg/day) or olive oil (sham-treated group) by oral gavage daily from preinjury day 1 to postinjury day 4. After vocal folds were injured under the endoscope, larynges were harvested for histological and immunohistochemical examinations on postinjury days 1, 3, 5, and 56, and quantitative real time polymerase chain reaction (PCR) on postinjury days 1 and 3.

The expression of 4-hydroxy-2-nonenal, which is an oxidative stress marker, was reduced significantly in the lamina propria of the Ast-treated group as compared to the sham-treated group. Histological examination showed significantly less tissue contraction with favorable deposition of hyaluronic acid in the lamina propria of the Ast-treated group compared to the sham-treated group. Real time PCR revealed significantly upregulated mRNA expression of basic fibroblast growth factor on postinjury day 1 and procollagen type I in the Ast-treated group compared to the sham-treated group.

These findings suggest that astaxanthin has the potential to prevent vocal fold scarring by regulating oxidative stress during the early phase of vocal fold wound healing.