Cytoskeleton of cells in vocal fold macula flava unphonated for a long period

Abstract

Cells in the maculae flavae (MFe) are inferred to be involved in the metabolism of extracellular matrices of the human vocal fold mucosa. The latest research has supported the hypothesis that the tension caused by phonation (vocal fold vibration) regulates the behavior of these cells in the MFe of the human vocal fold. Tensile and compressive strains have direct effects on cell morphology and structure including changes in cytoskeletal structure and organization. Cytoskeletons are one of the structures which play a role as mechanoreceptors for the cells. The microstructure of the intermediate filaments and the expression of their proteins were investigated regarding the cells in the MFe of the human vocal fold unphonated over a decade. The adult vocal fold mucosa of a 64-year-old male with cerebral hemorrhage unphonated for 11 years was investigated by immunohistochemistry and electron microscopy. The intermediate filaments in the cytoplasm of the cells had become fewer in number. And the expression of their characteristic proteins (vimentin, desmin, GFAP) was also reduced. The results of this study are consistent with the hypothesis that mechanotransduction caused by vocal fold vibration could possibly be a factor in regulating the function and fate of the cells in the MFe.

Keywords: Cytoskeleton; Human vocal fold; Larynx; Macula flava; Mechanotransduction; Unphonated vocal fold.