PRNP and Parkinson disease: Misfolded and prion proteins (PrP) are released in exosomes (Guo et al., 2015), particularly the ones implicated in neurodegenerative diseases such as Huntington’s, Alzheimer’s and Parkinson’s disease, including amyloid β, APP C-terminal fragments, Tau, α-synuclein, SOD1, and the PrP (Fevrier et al., 2004; Rajendran et al., 2006; Perez-Gonzalez et al., 2012; Saman et al., 2012; Grad et al., 2014).