Paraphenylenediamine induces apoptosis of Murine myeloma cells in a reactive oxygen species dependant mechanism

Paraphenylenediamine (p-PD) is the main aromatic amine used in the formulation of hair dyes. Epidemiologic studies have suggested that the use of p-PD based hair dyes might be related to increase risk of human malignant tumors including multiple myeloma and hematopoietic cancers. However, the toxicity of p-PD on myeloma cells has not been well elucidated yet. Therefore, the association between the cytotoxicity of p-PD and the reactive oxygen species (ROS) generation on murine myeloma cells P3X63Ag8.653 (P3) was evaluated. Treatment with p-PD decreases cell viability in a dose and time dependent manner. In addition, p-PD markedly enhanced lipid peroxidation. This increase was accompanied with a decrease in both glutathione reductase and superoxide dismutase activities. Furthermore, Pre-treatment of P3 cells with antioxidants, reduced glutathione or manganese II chloride, significantly inhibited p-PD induced cytotoxicity and ROS generation. Based on these