Hydrogen peroxide induces apoptosis of BJAB cells due to formation of hydroxyl radicals via intracellular iron-mediated Fenton chemistry in glucose oxidase-mediated oxidative stress.
The aim of this study was to determine if hydrogen peroxide (H2O2) generated by glucose oxidase (GO) induces apoptosis or necrosis of BJAB cells and which radical is the direct mediator of cell death. We found that GO produced H2O2 continuously in low concentrations, similar to in vivo conditions, and decreased proliferation and cell viability in a dose-dependent manner. The GO-mediated cytotoxicity resulted from apoptosis, and was confirmed by monitoring the cells after H33342/Annexin V/propidium iodide staining. Decreases of mitochondrial membrane potential and intracellular glutathione level were found to be critical events in the H2O2-mediated apoptosis. Additional experiments revealed that H2O2 exerted its apoptotic action through the formation of hydroxyl radicals via the Fenton rather than the Haber-Weiss reaction. Moreover, intracellular redox-active iron, but not copper, participated in the H2O2-mediated apoptosis.
Lee
Jeong-Chae
JC
Research Center of Bioactive Materials, Chonbuk National University, Chonju 561-756, Korea.
Son
Young-Ok
YO
Choi
Ki-Choon
KC
Jang
Yong-Suk
YS
D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D045744:Cell Line, Tumor; D005949:Glucose Oxidase / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D017665:Hydroxyl Radical; D007502:Iron Chelating Agents / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D051336:Mitochondrial Membranes / Q000187:drug effects / Q000502:physiology; D018384:Oxidative Stress / Q000502:physiology*
D000975:Antioxidants; D007502:Iron Chelating Agents; D017665:Hydroxyl Radical; D006861:Hydrogen Peroxide; D005949:Glucose Oxidase; D005978:Glutathione