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Many models of Parkinson's disease (PD) have succeeded in replicating dopaminergic neuron loss or α-synuclein aggregation but not the formation of classical Lewy bodies, the pathological hallmark of PD. Our cybrid model of sporadic PD was created by introducing the mitochondrial genes from PD patients into neuroblastoma cells that lack mitochondrial DNA. Previous studies using cybrids have shown that information encoded by mitochondrial DNA in patients contributes to many pathogenic features of sporadic PD. In this paper, we report the generation of fibrillar and vesicular inclusions in a long-term cybrid cell culture model that replicates the essential antigenic and structural features of Lewy bodies in PD brain without the need for exogenous protein expression or inhibition of mitochondrial or proteasomal function. The inclusions generated by PD cybrid cells stained with eosin, thioflavin S, and antibodies to α-synuclein, ubiquitin, parkin, synphilin-1, neurofilament, β-tubulin, the proteasome, nitrotyrosine, and cytochrome c . Future studies of these cybrids will enable us to better understand how Lewy bodies form and what role they play in the pathogenesis of PD. [ABSTRACT FROM AUTHOR]

Exposure of SH-SY5Y neuroblastoma or rat cortical neurons to diethylenetriamine–NO (DETA–NO) rapidly depolarized mitochondria. In SH-SY5Y DETA–NO activated caspase 3 and produced cell death. Mitochondrial depolarization in SH-SY5Y was visualized both with JC-1 accumulation and as dequenching of calcein fluorescence in mitochondria initially loaded with calcein-AM and tetramethylrhodamine methyl ester (TMRM). Calcein/TMRM-visualized mitochondrial depolarization was prevented by cyclosporin A (CsA) or ∼two-fold increased levels of BclXL protein. Dynamic imaging of mitochondrial potential (ΔψM) with TMRM showed that DETA–NO induced cycles of mitochondrial depolarization/repolarization (“flickering”). Fifteen–30 min of DETA–NO exposure caused high-frequency flickering with small peak size; 2 h of DETA–NO produced large peaks with prolonged depolarization. NO-induced flickering but not that from Bax was blocked by the calcium uniporter antagonist Ru360. Our findings show rapid-onset, dynamic regulation of ΔψM by NO, implying that neuroprotective therapies for brain ischemia target cell death processes downstream of effects of NO on mitochondria. [Copyright &y& Elsevier]