Vitamin A deficiency causes metaplasia in vocal fold epithelium: a rat study.
OBJECTIVE
The roles of vitamin A in the vocal fold epithelium are not well documented, although vitamin A has been used as a conservative treatment for laryngeal leukoplakia. The purpose of this study was to analyze the roles of vitamin A in vocal fold epithelial differentiation.


METHODS
Vitamin A-deficient (VAD) rats were generated, and the abnormality of their vocal fold epithelium was examined by hematoxylin and eosin staining and immunohistochemical analysis for keratin 10 and transglutaminase (TGase) 1.


RESULTS
The VAD experimental rats exhibited orthokeratosis of the vocal fold epithelium. Keratin 10 and TGase 1 were up-regulated in the epithelium of the VAD rats.


CONCLUSIONS
It is suggested that vitamin A suppresses TGase 1 expression in normal vocal folds to inhibit keratinization, and that the TGase 1 up-regulation caused by vitamin A deficiency may be related to the formation of metaplasia in the laryngeal epithelium.
Tateya
Ichiro
I
Department of Otolaryngology, Kyoto Katsura Hospital, 17 Yamada Hirao-cho, Nishikyo-ku, Kyoto 615-8256, Japan.
Tateya
Tomoko
T
Surles
Rebecca Lynn
RL
Kanehira
Kazunori
K
Tanumihardjo
Sherry
S
Bless
Diane M
DM
D000818:Animals; D004848:Epithelium / Q000473:pathology; D008679:Metaplasia / Q000209:etiology; D051381:Rats; D011503:Transglutaminases / Q000096:biosynthesis; D014802:Vitamin A Deficiency / Q000150:complications* / Q000201:enzymology; D014827:Vocal Cords / Q000473:pathology*
D011503:Transglutaminases; C105804:transglutaminase 1