Publication Type:Journal Article
Source:Neurochemistry International, Volume 50, Issue 6 (2007)
Other Number:PMCID: PMC1950670
Keywords:Caspases, gene expression, mitochondria, oxidative stress, Parkinson’s disease, PKCdelta
Oxidative stress and apoptotic cell death have been implicated in the dopaminergic cell loss that characterizes Parkinson’s disease. While factors contributing to apoptotic cell death are not well characterized, oxidative stress is known to activate an array of cell signaling molecules that participate in apoptotic cell death mechanisms. We investigated oxidative stress-induced cytotoxicity of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) in three cell lines, the dopaminergic mesencephalon-derived N27 cell line, the GABAergic striatum-derived M213-20 cell line, and the hippocampal HN2-5 cell line. N27 cells were more sensitive to H<sub>2</sub>O<sub>2</sub>-induced cell death than M213-20 and HN2-5 cells. H<sub>2</sub>O<sub>2</sub> induced significantly greater increases in caspase-3 activity in N27 cells than in M213-20 cells. H<sub>2</sub>O<sub>2</sub>-induced apoptotic cell death in N27 cells was mediated by caspase-3-dependent proteolytic activation of PKCδ. Gene expression microarrays were employed to examine the specific transcriptional changes in N27 cells exposed to 100 μM H<sub>2</sub>O<sub>2</sub> for 4 hrs. Changes in genes encoding pro- or anti-apoptotic proteins included up-regulation of BIK, PAWR, STAT5B, NPAS2, Jun B, MEK4, CCT7, PPP3CC and PSDM3, while key down-regulated genes included BNIP3, NPTXR, RAGA, STK6, YWHAH, and MAP2K1. Overall, the changes indicate a modulation of transcriptional activity, chaperone activity, kinase activity, and apoptotic activity that appears highly specific, coordinated and relevant to cell survival. Utilizing this <em>in vitro</em> model to identify novel oxidative stress-regulated genes may be useful in unraveling the molecular mechanisms underlying dopaminergic degeneration in Parkinson’s disease.