Fig 5. Working model for the Pathogenesis of PD.
The vital mitochondrial network is maintained by the quality control (QC) system (top, also see in Figure 1). In pathological states of PD, cellular stress or damage cause the excess of damaged mitochondria, then overwhelm the QC system (middle). Disruption of mitochondrial QC system also accumulates damaged mitochondria (bottom). Both pathological states may cause the collapse of the cellular environment following by the cell death.