Abstract
Loss-of-function mutations in the parkin gene have recently been shown to be responsible for autosomal recessive juvenile Parkinsonism. However, the exact mechanism of pathogenesis remains unclear. This study explores the effect of Parkin downregulation on dopaminergic cells in Parkinson’s disease. We generated small interfering RNA plasmids that target the parkin gene and transfected them into PC12 cells to mimic in vivo loss-of-function. We found that these small plasmids were able to effectively inhibit endogenous Parkin expression in PC12 cells. Downregulation of Parkin decreased the amount of glutathione and superoxide dismutase activity without affecting the amount of malondialdehyde. Moreover, Parkin knockdown rendered PC12 cells more susceptible to cell death induced by the proteasome inhibitor lactacystin. These results indicate that downregulation of Parkin may damage the antioxidation defenses of dopaminergic cells and increase their susceptibility to proteasome inhibitor-induced toxicity.
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Acknowledgments
We would like to thank Professor Youxin Jin for the plasmid pUB and the plasmid pEGFP-C1. This work was funded by the National Program of Basic Research (2006cb500700) of China, the National Natural Science Foundation of China (30471918), and Shanghai Key Project of Basic Science Research (04DZ14005).
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Yang, H., Zhou, HY., LI, B. et al. Downregulation of Parkin Damages Antioxidant Defenses and Enhances Proteasome Inhibition-Induced Toxicity in PC12 Cells. Jrnl Neuroimmune Pharm 2, 276–283 (2007). https://doi.org/10.1007/s11481-007-9082-2
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DOI: https://doi.org/10.1007/s11481-007-9082-2