Effects of hydrogen peroxide on mitochondrial gene expression of intestinal epithelial cells

摘要： <正> AIM:To study the effects of hydrogen peroxide onmitochondrial gene expression of intestinal epithelial cells inin vitro model of hydrogen peroxide-stimulated SW-480 cells.METHODS:RNA of hydrogen peroxide-induced SW-480cells was isolated,and reverse-transcriptional polymerasechain reaction was performed to study gene expression ofATPase subunit 6,ATPase subunit 8,cytochrome c oxidasesubunit Ⅰ(COI),cytochrome coxidase subuit Ⅱ(COⅡ)andcytochrome c oxidase subunit Ⅲ(COⅢ).Mitochondria wereisolated and activities of mitochondrial cytochrome c oxidaseand ATPase were also measured simultaneously.RESULTS:Hydrogen peroxide led to differential expressionof mitochondrial genes with some genes up-regulated ordown-regulated in a dose dependent manner.Differenceswere very obvious in expressions of mitochondrial genes ofcells treated with hydrogen peroxide in a concentration of400 μmol/L or 4 mmol/L.In general,differential expressionof mitochondrial genes was characterized by up-regulationof mitochondrial genes in the concentration of 400 μmol/Land down-regulation in the concentration of 4 mmol/L.Inconsistence with changes in mitochondrial gene expressions,hydrogen peroxide resulted in decreased activities ofcytochrome c oxidase and ATPase.CONCLUSIONS:The differential expression of mitochondrialgenes encoding cytochrome c oxidase and ATPase is involvedin apoptosis of intestinal epithelial cells by affecting activitiesof cytochorme c oxidase and ATPase. ... （共6页）