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Published on: June 13, 2017
Therapeutic potential of growth factors for aging voice
Shigeru Hirano1, Diane M Bless, Alejandro Muñoz del Río
1From the Department of Bronchoesophagology, Kyoto National Hospital, Kyoto, Japan.
Objectives/Hypothesis:
It has been reported that in aged vocal folds, dense collagen deposition takes place and hyaluronic acid decreases in the lamina propria, which are thought to contribute to the vocal problems occurring with age (presbyphonia). To restore aged vocal folds to their younger state, it seems crucial to address these age-related lamina propria changes. Intervention that might increase hyaluronic acid and decrease collagen would appear to be a potentially useful approach. The present study examined the effects of growth factors on aged fibroblasts in terms of the production of hyaluronic acid and collagen type I.
Study Design:
In vitro study using animal model.
Methods:
Fibroblasts were harvested from young and aged rat vocal folds and cultured with or without hepatocyte growth factor and/or basic fibroblast growth factor at different concentrations. Subsequently, the production of hyaluronic acid and collagen type I was examined in the supernatant culture media using enzyme-linked immunosorbent assay.
Results:
Aged fibroblasts produced less hyaluronic acid than younger fibroblasts. When aged and young fibroblasts were cultured with basic fibroblast growth factor, hyaluronic acid production increased and collagen type I production decreased regardless of the concentration, whereas the effects of hepatocyte growth factor appeared to vary with concentration. The basic fibroblast growth factor also was associated with stimulation of growth of aged fibroblasts.
Conclusion:
The present results suggest that growth factors, especially basic fibroblast growth factor, may have therapeutic potential in restoration of aged vocal fold.
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