Evaluation of Cr (VI) induced Neurotoxicity and Oxidative Stress in PC12 Cells

Authors
A. Dashti
M. Soodi
N. Amani
Department of Toxicology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
Abstract
Objective: Hexavalent chromium [Cr (VI)] compounds are well-known environmental contaminants generated from industrial processes. Several studies have reported the harmful effects of Cr (VI) on different organs, however, little is known about neurotoxic effects of Cr (VI). The aim of this study is to investigate the toxic effects of Cr (VI) on PC12 cells.
Methods: PC12 cells were cultured following standard protocol and exposed to various concentrations (1-100 μM) of potassium dichromate (K2Cr2O7) for 24, 48 and 72 h. After exposure, cell viability was measured by the MTT assy. Also following exposure, production of reactive oxygen species (ROS) and lipid peroxidation were measured.
Results: Potassium dichromate induced significant cell death in PC12 cells. The IC50 values for cytotoxicity were 22.02 for 24 h, 1.88 for 48 h, and 1.85 for 72 h of exposure. Significant differences between IC50 for 24 h of exposure compared to 48 and 72 h of exposure were observed (p<0.05). ROS production and lipid peroxidation significantly increased in the Cr (VI) treated groups compared to the control group (p<0.05).
Conclusion: The results indicated that Cr (VI) induced dose and time dependent cytotoxicity in PC12 cells which indicated neurotoxic effects of Cr (VI). Mechanisms of Cr (VI) induced toxicity have not been fully determined, however increased production of ROS and lipid peroxidation in Cr (VI) treated groups demonstrated that oxidative stress might be involved in neurotoxicity of Cr (VI).

Keywords

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Pathobiology Reserach
Volume 18, Issue 1
April 2015
Pages 55-65