Asunto(s)
Enfermedad de la Neurona Motora/genética , Enfermedad de la Neurona Motora/patología , Proteínas Asociadas a Matriz Nuclear/genética , Enfermedades Faríngeas/genética , Enfermedades Faríngeas/patología , Proteínas de Unión al ARN/genética , Disfunción de los Pliegues Vocales/genética , Disfunción de los Pliegues Vocales/patología , Adulto , Edad de Inicio , Anciano , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de la Neurona Motora/complicaciones , Mutación/genética , Linaje , Enfermedades Faríngeas/complicaciones , Fenotipo , Disfunción de los Pliegues Vocales/complicacionesRESUMEN
OBJECTIVES/HYPOTHESIS: Vocal fold scarring is one of the most challenging laryngeal disorders to treat. Hyaluronic acid (HA) is the main component of lamina propria, and it plays an important role in proper vocal fold vibration and is also thought to be important in fetal wound healing without scarring. Although several animal models of vocal fold scarring have been reported, little is known about the way in which HA is maintained in vocal folds. The purpose of this study was to clarify the homeostasis of HA by examining the expression of hyaluronan synthase (Has) and hyaluronidase (Hyal), which produce and digest HA, respectively. STUDY DESIGN: Experimental prospective animal study. METHODS: Vocal fold stripping was performed on 38 Sprague-Dawley rats. Vocal fold tissue was collected at five time points (3 days-2 months). Expression of HA was examined by immunohistochemistry, and messenger RNA (mRNA) expression of Has and Hyal was examined by real-time polymerase chain reaction and in-situ hybridization. RESULTS: In scarred vocal folds, expression of Has1 and Has2 increased at day 3 together with expression of HA and returned to normal at 2 weeks. At 2 months, Has3 and Hyal3 mRNA showed higher expressions than normal. CONCLUSIONS: Expression patterns of Has and Hyal genes differed between normal, acute-scarred, and chronic-scarred vocal folds, indicating the distinct roles of each enzyme in maintaining HA. Continuous upregulation of Has genes in the acute phase may be necessary to achieve scarless healing of vocal folds.
Asunto(s)
Cicatriz/genética , Regulación de la Expresión Génica , Homeostasis/fisiología , Ácido Hialurónico/genética , ARN Mensajero/genética , Disfunción de los Pliegues Vocales/genética , Pliegues Vocales/metabolismo , Animales , Cicatriz/metabolismo , Cicatriz/patología , Modelos Animales de Enfermedad , Ácido Hialurónico/biosíntesis , Inmunohistoquímica , Masculino , Estudios Prospectivos , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , Disfunción de los Pliegues Vocales/metabolismo , Disfunción de los Pliegues Vocales/patología , Pliegues Vocales/patologíaRESUMEN
OBJECTIVES/HYPOTHESIS: Reactive oxygen species (ROS) are associated with aging. Astaxanthin (AST) is a strong antioxidant and has been reported to prevent various ROS-induced diseases. In the current study, we investigated the effect of AST on age-associated histological and mRNA changes of vocal folds. STUDY DESIGN: Prospective animal experiment with control. METHODS: Six-month-old Sprague-Dawley rats were fed on a normal powder diet with 0.01% (w/w) AST (aged AST-treated group) or without AST (aged sham-treated group). After 12 months of feeding, the larynges were harvested for histology, immunohistochemical detection of 4-hydroxy-2-nonenal (4-HNE), and quantitative real-time polymerase chain reaction for basic fibroblast growth factor (bFGF) and hepatocyte growth factor (HGF). Thirteen-week-old rats were used as a young control group (young group). RESULTS: The expression of 4-HNE, an oxidative stress marker, significantly increased in the two aged groups compared with the young group. Histological examination showed that the deposition of hyaluronic acid in the lamina propria (LP) was significantly reduced in the aged sham-treated group compared with the young group, but no significant difference was observed between the aged AST-treated group and the young group. There were no significant differences in the mRNA expression of bFGF and HGF between the aged AST-treated group and the young group, although the expression of these genes was significantly reduced in the aged sham-treated group as compared with the young group. CONCLUSIONS: These results suggest that AST has the potential to attenuate age-associated changes of vocal folds.