MANF and Parkinson disease: While MANF demonstrated potential to rescue cell bodies of dopamine neurons in the substantia nigra (SN) pars compacta (SNpc) in a 6-OHDA rat model, its protective effect on neuronal axons (the fibers of dopamine neurons in the striatum) was modest or absent (Voutilainen et al., 2009, 2011), making it a dubious NTF candidate for clinical trials in PD patients.