Vanadate Induces p53 Transactivation through Hydrogen Peroxide and Causes Apoptosis

• Published in: The Journal of biological chemistry Vol. 275; no. 42; pp. 32516 - 32522
• Main Authors: Huang, Chuanshu, Zhang, Zhuo, Ding, Min, Li, Jingxia, Ye, Jianping, Leonard, Stephen S., Shen, Han-Ming, Butterworth, Leon, Lu, Yongju, Costa, Max, Rojanasakul, Yongyut, Castranova, Vincent, Vallyathan, Val, Shi, Xianglin
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 20.10.2000; American Society for Biochemistry and Molecular Biology
• Subjects: Acetylcysteine - pharmacology; Animals; Apoptosis - drug effects; Apoptosis - physiology; Cell Line; DNA Fragmentation; Electron Spin Resonance Spectroscopy; Genes, p53; Hydrogen Peroxide - pharmacology; Intracellular Membranes - physiology; Kinetics; Membrane Potentials - drug effects; Membrane Potentials - physiology; Mice; Mitochondria - physiology; Reactive Oxygen Species - metabolism; Skin; Transcription, Genetic - drug effects; Transcriptional Activation - drug effects; Transcriptional Activation - physiology; Transfection; Tumor Suppressor Protein p53 - genetics; vanadate; Vanadates - pharmacology
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M005366200

Vanadium is a metal widely distributed in the environment. Although vanadate-containing compounds exert potent toxic effects on a wide variety of biological systems, the mechanisms controlling vanadate-induced adverse effects remain to be elucidated. The present study investigated the vanadate-induced p53 activation and involvement of reactive oxygen species (ROS) in p53 activation as well as the role of p53 in apoptosis induction by vanadate. Exposure of mouse epidermal JB6 cells to vanadate led to transactivation of p53 activity in a time- and dose-dependent manner. It also caused mitochondrial damage, apoptosis, and generated ROS. Scavenging of vanadate-induced H2O2 byN-acetyl-l-cysteine (a general antioxidant) or catalase (a specific H2O2 inhibitor), or the chelation of vanadate by deferoxamine, resulted in inhibition of p53 activation and cell mitochondrial damage. In contract, an increase in H2O2 generation in response to superoxide dismutase or NADPH enhanced these effects caused by vanadate. Furthermore, vanadate-induced apoptosis occurred in cells expressing wild-type p53 (p53+/+) but was very weak in p53-deficient (p53−/−) cells. These results demonstrate that vanadate induces p53 activation mainly through H2O2 generation, and this activation is required for vanadate-induced apoptosis.