Glycolytic activity of the tissue stem cells in the macula flava of the human vocal fold

OBJECTIVES: In our previous studies, the features of the mitochondria of tissue stem cells in the maculae flavae of the human vocal fold suggested that their metabolic activity and oxidative phosphorylation was low. This study investigated the metabolic activity, especially glycolysis of the tissue stem cells in the maculae flavae of the human adult vocal fold. STUDY DESIGN: Histologic analysis of the human vocal folds. METHODS: Three normal human adult vocal folds obtained from autopsy cases were investigated using immunohistochemistry. RESULTS: Among the three phenotypes of cells in the human adult maculae flavae, the vocal fold stellate cell‐like cells strongly expressed glucose transporter‐1. Three phenotypes of cells in the human adult maculae flavae expressed glycolytic enzymes (hexokinase II, glyceraldehyde‐3‐phosphate dehydrogenase and lactate dehydrogenase A) indicating the tissue stem cells in the maculae flavae relied more on glycolysis. The cells did not express phosphofructokinase‐1 but did express glucose‐6‐phosphate dehydrogenase indicating the cells relied more on the pentose phosphate pathway. The cells expressed lactate dehydrogenase A indicating the maculae flavae of the human adult vocal fold was likely to be an anaerobic microenvironment. CONCLUSIONS: The present study is consistent with the hypothesis that the tissue stem cells in the maculae flavae of the human vocal fold seem to rely more on anaerobic glycolysis, especially by the pentose phosphate pathway, for energy supply. The metabolism of the tissue stem cells in the maculae flavae of the human adult vocal fold is likely to prevent toxic reaction oxygen species and be favorable to maintaining the stemness and undifferentiated states of the tissue stem cells in the stem cells system. LEVEL OF EVIDENCE: NA.