PCSK1 and Parkinson disease: Regarding PD models, Iannielli et al. [142] showed that three-week treatment of mice with Nec-1 and Nec-1s provided protection against MPTP-induced dopamine neuron loss in the substantia nigra pars compacta (SNpc), and this protective effect was associated with reduced intracellular oxidative stress levels (4-hydroxynonenal).