α-Synuclein-mediated mitochondrial translocation of cofilin-1 leads to oxidative stress and cell apoptosis in PD

Parkinson's disease (PD) is characterized by the accumulation of misfolded α-synuclein protein and the loss of dopaminergic neurons in the substantia nigra. Abnormal α-synuclein aggregates form toxic Lewy bodies, ultimately inducing neuronal injury. Mitochondrial dysfunction was reported to be involved in the neurotoxicity of α-synuclein aggregates in PD. However, the specific mechanism by which abnormal α-synuclein aggregates cause mitochondrial disorders remains poorly defined. Previously, we found that cofilin-1, a member of the actin-binding protein, regulates α-synuclein pathogenicity by promoting its aggregation and spreading <i>in vitro and in vivo</i>. In this study, we further investigated the effect of cofilin-1 on α-synuclein induced mitochondrial damage. We discovered that α-synuclein aggregates accelerate the translocation of cofilin-1 to mitochondria, promote its combination with the mitochondrial outer membrane receptor Tom 20, and ultimately activate the oxidative damage and apoptosis pathway in mitochondria. All these results demonstrate the important regulatory role of cofilin-1 in the mitochondrial neurotoxicity of pathological α-synuclein during the progression of PD.